CN111397109B

CN111397109B - Air mixing control method and air mixing control device of air conditioning system

Info

Publication number: CN111397109B
Application number: CN202010196455.0A
Authority: CN
Inventors: 李学良; 蒋贤国; 梁洪启
Original assignee: Hisense Shandong Air Conditioning Co Ltd
Current assignee: Hisense Air Conditioning Co Ltd
Priority date: 2020-03-19
Filing date: 2020-03-19
Publication date: 2021-08-27
Anticipated expiration: 2040-03-19
Also published as: CN111397109A

Abstract

The application discloses a mixed air control method and a mixed air control device of an air conditioning system, wherein the mixed air control method comprises the following steps of executing in each period T: determining the high level signal duration and the low level signal duration of a PWM signal, and determining the dead time of the PWM signal; starting a timer, and controlling a PWM (pulse width modulation) port to output a high level signal according to the duration of the high level signal; based on the dead time, sending out a mixed wind mode forbidding instruction; after the dead time, issuing a mixed wind mode enabling instruction; starting a timer, and controlling a PWM (pulse width modulation) port to output a low level signal according to the duration of the low level signal; and sending out a mixed wind mode disabling instruction based on the dead time. According to the air mixing control method, the dead zone time is inserted between the high and low level signals to control the two subsystems to not supply air, so that the breathing type air mixing is realized, condensation in the air mixing mode can be fundamentally eliminated, and the use experience of the air conditioning system is improved.

Description

Air mixing control method and air mixing control device of air conditioning system

Technical Field

The application belongs to the technical field of air conditioning equipment manufacturing, and particularly relates to a wind mixing control method and a wind mixing control device of an air conditioning system.

Background

The passive house technology is widely concerned due to the excellent characteristics of energy conservation and environmental protection. The air conditioning system in the passive room technology integrates a fresh air system and an internal circulation system. When the wind mixing mode is opened to passive room, the cold wind (the temperature is low) through the evaporimeter mixes in the wind mixing district with the hot-blast (the temperature is high) through total heat exchanger, produces the condensation, influences the result of use, can even be blown out by air supply fan under the severe condition, influences user experience.

In the related art, in order to solve the problem of condensation in a large amount of air mixing areas in a mixed air mode (fresh air + internal circulation refrigeration), the following solutions are adopted: the water pan is arranged at the mixing position of the cold air and the hot air, and the condensed water generated on the volute of the air supply fan can be converged to the water pan to be discharged. But this technique does not fundamentally solve the condensation problem, and the water collector that sets up more has increased the cost, if the comdenstion water on the spiral case is too much, has the risk that is blown out by air supply fan.

In addition, some passive rooms directly forbid the air mixing mode, namely the refrigeration mode and the fresh air mode cannot be started simultaneously, and the mode cannot meet the requirement of a user on using the air mixing mode.

Disclosure of Invention

The present application is directed to solving at least one of the problems in the prior art.

In a first aspect, the present application discloses a method for controlling air mixing in an air conditioning system, the air conditioning system comprising: an internal circulation subsystem and a fresh air subsystem; the air mixing control method comprises the following steps of executing in each period T: determining the high level signal duration and the low level signal duration of a PWM signal, and determining the dead time of the PWM signal; starting a timer, and controlling a PWM (pulse width modulation) port to output a high level signal according to the duration of the high level signal; based on the dead time, sending out a mixed wind mode forbidding instruction; after the dead time, issuing a mixed wind mode enabling instruction; starting a timer, and controlling a PWM (pulse width modulation) port to output a low level signal according to the duration of the low level signal; based on the dead time, sending out a mixed wind mode forbidding instruction; one of the high level signal and the low level signal is used for controlling the air supply of the internal circulation subsystem and controlling the closing of the fresh air subsystem; the other one of the high level signal and the low level signal is used for controlling the internal circulation subsystem to be closed and controlling the fresh air subsystem to supply air; and the wind mixing mode disabling instruction is used for controlling the internal circulation subsystem and the fresh air subsystem to be closed.

According to the air mixing control method of the air conditioning system, the high-low level signals are controlled and output in each period, and the dead time is inserted between the high-low level signals, so that air is not supplied to the two subsystems, the breathing type air mixing is realized, condensation in the air mixing mode can be eliminated fundamentally, and the use experience of the air conditioning system is improved.

In some embodiments, the determining the high-level signal duration and the low-level signal duration of the PWM signal includes: determining a duty cycle of the PWM signal; determining a high level signal duration based on the period T and the determined duty cycle; determining a low level signal duration based on the period T and the determined duty cycle.

In some embodiments, the determining the duty cycle of the PWM signal comprises: acquiring a set temperature, a collected ambient temperature and a collected heat exchanger temperature of the air conditioning system; determining the duty cycle based on the set temperature, the ambient temperature, and the heat exchanger temperature.

In some embodiments, said determining said duty cycle based on said set temperature, said ambient temperature and said heat exchanger temperature comprises: determining t_p≤T_{CRITICAL_POINT}Setting D to be 1; determination of T_{CRITICAL_POINT}＜t_p＜T_{PROTECT_POINT}，|t_outs-t_set| > Δ T, and D is set to be more than or equal to 0.7 and less than 1; determination of T_{CRITICAL_POINT}＜t_p＜T_{PROTECT_POINT}，|t_outs-t_setDelta T is smaller than | and D is set to be more than 0.5 and less than 0.7; determining t_p≥T_{PROTECT_POINT}，|t_outs-t_set| > delta T, and D is set to be more than 0.3 and less than or equal to 0.5; determining t_p≥T_{PROTECT_POINT}，|t_outs-t_setDelta T is smaller than | and D is more than 0 and less than or equal to 0.3; wherein T is_{PROTECT_POINT}Is a first safety temperature, T_{CRITICAL_POINT}Is the second safety temperature, t_pIs the temperature of the heat exchanger, t_setFor the set temperature, t_outsAnd D is the duty ratio and is a delta T temperature difference preset value.

In some embodiments, the high level signal and the low level signal are used for controlling the opening and closing of air valves of the internal circulation subsystem and the fresh air subsystem; the determining the dead time of the PWM signal includes: air supply flow F of air supply fan based on air conditioning system_sDetermining the dead time t by the air duct coefficient K of the indoor unit of the air conditioning system, the volume V of the indoor unit, the flow cross-sectional area S of the air supply fan and the response time delta t of the air valve_dead。

In some embodiments, the air supply flow F of the air supply fan based on the air conditioning system_sDetermining the dead time t by the air duct coefficient K of the indoor unit of the air conditioning system, the volume V of the indoor unit, the flow cross-sectional area S of the air supply fan and the response time delta t of the air valve_deadInvolving the application of formulas

Determining the dead time t_dead。

In some embodiments, during the current cycle, if t_p≤T_{CRITICAL_POINT}Shortening the period T, T of the next cycle_{CRITICAL_POINT}Is a preset second safety temperature, t_pIs the collected heat exchanger temperature.

In some embodiments, the method for controlling the air mixing of the air conditioning system includes: obtaining the temperature t of the heat exchanger_pDetermining t_p≤T_{CRITICAL_POINT}Setting D to be 1; after the time delay delta T, the temperature T of the heat exchanger is obtained again_pDetermining t_p≤T_{CRITICAL_POINT}Sending a cold protection fault signal, wherein the delay delta T is a preset time, T_{CRITICAL_POINT}Is a preset second safety temperature, t_pAnd D is the duty ratio of the PWM signal for the acquired temperature of the heat exchanger.

In a second aspect, the present application provides a mixed air control device of an air conditioning system, the air conditioning system including: internal loop subsystem and new trend subsystem, mix wind controlling means includes: the time length determining module is used for determining the time length of a high level signal and the time length of a low level signal of a PWM signal and determining the dead time of the PWM signal; a timer; the control module is used for starting a timer and controlling the PWM port to output a high level signal according to the duration of the high level signal; sending out a mixed wind mode forbidding instruction; after the dead time, issuing a mixed wind mode enabling instruction; starting a timer, and controlling a PWM (pulse width modulation) port to output a low level signal according to the duration of the low level signal; sending out a mixed wind mode forbidding instruction; one of the high level signal and the low level signal is used for controlling the air supply of the internal circulation subsystem and controlling the closing of the fresh air subsystem; the other one of the high level signal and the low level signal is used for controlling the internal circulation subsystem to be closed and controlling the fresh air subsystem to supply air; and the wind mixing mode disabling instruction is used for controlling the internal circulation subsystem and the fresh air subsystem to be closed.

In a third aspect, the present application provides an air conditioning system comprising: an internal circulation subsystem, a fresh air subsystem and the air mixing control device.

In a fourth aspect, the present application provides an electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor executes the program to implement the steps of the air mixing control method of the air conditioning system as described in any one of the above.

In a fifth aspect, the present application provides a non-transitory computer readable storage medium having stored thereon a computer program which, when executed by a processor, implements the steps of the method of controlling the mixing of air of an air conditioning system as recited in any of the above.

The advantages of the air mixing control device, the air conditioning system, the electronic device, and the computer-readable storage medium are the same as those of the above method over the prior art, and are not described herein again.

Additional aspects and advantages of the present application will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the present application.

Drawings

The above and/or additional aspects and advantages of the present application will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a schematic block diagram of an air conditioning system according to an embodiment of the present application;

FIG. 2 is a waveform diagram of a periodic signal (or PWM signal) according to an embodiment of the present application;

FIG. 3 is a schematic diagram of a control circuit according to an embodiment of the present application;

FIG. 4 is a flow chart of a method of controlling mixing of wind according to an embodiment of the application;

fig. 5 is a flowchart of a control method of an air conditioning system according to an embodiment of the present application;

FIG. 6 is a flow chart of a method of controlling mixing of wind according to an embodiment of the present application;

fig. 7 is a flowchart of a supercooling protection method in a mixed air control method according to an embodiment of the present application;

fig. 8 is a schematic structural diagram of a wind mixing control device according to an embodiment of the present application;

fig. 9 is a schematic structural diagram of an electronic device according to an embodiment of the present application.

Reference numerals:

a temperature control air valve 11, a purification air valve 12, a fresh air valve 13,

an internal circulation filter device 21, a fresh air first filter device 22, a fresh air second filter device 23,

an internal circulation air return opening 31, a fresh air return opening 32, an indoor air supply opening 33, an outdoor fresh air opening 34, an outdoor air outlet 35,

a blowing fan 41, an exhaust fan 42, a total heat exchanger 43, a heat exchanger 44, a wind mixing area 45,

the signal drives the sub-circuit 51 and the dead band insertion sub-circuit 52.

Detailed Description

Reference will now be made in detail to embodiments of the present application, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present application and are not to be construed as limiting the present application.

An air conditioning system of an embodiment of the present application is first described with reference to fig. 1.

As shown in fig. 1, the air conditioning system includes an internal circulation subsystem and a fresh air subsystem, and an air outlet of the fresh air subsystem and an air outlet of the internal circulation subsystem are both communicated with an indoor air supply outlet 33 of the air conditioning system through an air mixing area 45. The air conditioning system may be an air handling all-in-one machine.

The internal circulation subsystem is used for adjusting the temperature of indoor air, and includes a heat exchanger 44, a flow channel for flowing through a heat exchange medium is arranged in the heat exchanger 44, the heat exchanger 44 is used for exchanging heat between the heat exchange medium and the air, the heat exchanger 44 may be a coil heat exchanger, the internal circulation subsystem may include a heat exchange circulation loop, the heat exchanger 44 is one of the heat exchange circulation loops, and when the internal circulation subsystem executes a refrigeration mode, the heat exchanger 44 is used as an evaporator. Of course, in other embodiments, the internal circulation subsystem may also have a heating mode, and the heat exchanger 44 may be used as a condenser when the internal circulation subsystem performs a cooling mode. Other structures such as a compressor, an expansion valve and the like in the heat exchange circulation loop are not described in detail herein.

When the internal circulation subsystem works, the temperature control air valve 11 is opened, the air supply fan 41 works, indoor air is sucked into an air channel of the internal circulation subsystem from the internal circulation air return opening 31, the internal circulation filter device 21 can be arranged at the internal circulation air return opening 31, and the air is filtered through the internal circulation filter device 21. Wherein, the internal circulation filter device 21 can be a filter screen.

The air sucked into the air duct exchanges heat at the heat exchanger 44, for example, when the internal circulation subsystem performs a cooling mode, the heat exchanger 44 serves as an evaporator, the heat-exchanged air flows into the air mixing area 45, and is then sent into the room through the indoor air supply opening 33 under the driving of the air supply fan 41, so that the indoor temperature is adjusted.

The three arrows in fig. 1 show the direction of flow of the air in the internal circulation.

The fresh air subsystem is used for sending fresh air into the room, and the fresh air subsystem comprises a total heat exchanger 43, and the total heat exchanger 43 is used for heat exchange between air and air.

When the fresh air subsystem works, the exhaust fan 42 works, indoor foul air is sucked into a return air duct of the fresh air subsystem from the fresh air return opening 32 and then flows into an air flow channel of the total heat exchanger 43, wherein the fresh air return opening 32 can be provided with a fresh air first filtering device 22, air is filtered by the fresh air first filtering device 22, and the fresh air first filtering device 22 can be a filter screen; when the air supply fan 41 works, outdoor fresh air is sucked into the fresh air duct from the outdoor fresh air inlet 34 and then flows into the other air flow passage of the total heat exchanger 43, wherein the second fresh air filtering device 23 can be arranged at the outdoor fresh air inlet 34, and air is filtered by the second fresh air filtering device 23, wherein the second fresh air filtering device can be a filter screen; the heat exchange between the foul air and the fresh air is performed at the outlet of the total heat exchanger 43, the foul air after heat exchange is exhausted to the outside through the outdoor air outlet 35 under the driving of the air exhaust fan 42, and the fresh air after heat exchange flows into the air mixing area 45 and is sent into the room through the indoor air supply outlet 33 under the driving of the air supply fan 41, so that the fresh air is sent into the room.

The double arrows in FIG. 1 show the flow direction of the foul air when the fresh air is supplied; the single arrow shows the direction of flow of the fresh air when it is fresh.

For example, in summer, the indoor temperature is significantly lower than the outdoor temperature, indoor foul air exchanges heat with fresh air at the total heat exchanger 43, the fresh air is introduced into the room after the temperature of the fresh air is raised, and the foul air is discharged to the outside after the temperature of the foul air is lowered.

In some embodiments, the air conditioning system may further include a purge air valve 12, and the intake air duct of the internal circulation subsystem and the exhaust air duct of the fresh air system may be selectively communicated through the purge air valve 12. In other words, the purge air valve 12 is provided between the internal circulation return air inlet 31 and the outdoor air outlet 35.

Thus, the air conditioning system can have a purification mode, in which the purification air valve 12 is opened, the fresh air valve 13 is opened, the temperature control air valve 11 is closed, the air supply fan 41 and the air exhaust fan 42 are both opened, outdoor fresh air is sucked into a fresh air duct from the outdoor fresh air inlet 34, passes through the air mixing area 45 and is sent into the room from the indoor air supply outlet 33, indoor foul air is sucked into an air inlet duct of the internal circulation subsystem from the internal circulation air return inlet 31 and is exhausted to the outside through the purification air valve 12 and the outdoor air outlet 35 in sequence. In the purification mode, the foul air and the fresh air do not need to be subjected to heat exchange by the total heat exchanger 43, so as to prevent the indoor temperature from being improperly adjusted. The purification mode is similar to the fresh air mode, except that the indoor foul air is exhausted in the purification mode without passing through the total heat exchanger 43, and the indoor foul air is exhausted to the outside through the internal circulation air return opening 31, the purification air valve 12 and the outdoor air outlet 35.

A method of controlling the air-mix of the air conditioning system according to the embodiment of the present application will be described below with reference to fig. 1 to 7.

As shown in fig. 1, the air conditioning system includes: the air outlet of the fresh air subsystem and the air outlet of the fresh air subsystem are both communicated with the air supply outlet of the air conditioning system through the air mixing area 45 in some embodiments. The specific structure of the air conditioning system may refer to the description of the embodiments of the air conditioning system described above.

As shown in fig. 4, the method for controlling mixed wind in the embodiment of the present application includes, in each period T, performing the following steps:

and S100, determining the high-level signal duration and the low-level signal duration of the PWM signal, and determining the dead time of the PWM signal.

And step S200, starting a timer, and controlling the PWM port to output a high-level signal according to the duration of the high-level signal.

And step S300, sending out a wind mixing mode disabling instruction based on the dead time.

Step S400, after the dead time, a mixed wind mode enabling instruction is sent out.

And step S500, starting a timer, and controlling the PWM port to output a low level signal according to the duration of the low level signal.

And step S600, sending out a wind mixing mode disabling instruction based on the dead time.

One of the high level signal and the low level signal is used for controlling the air supply of the internal circulation subsystem and controlling the closing of the fresh air subsystem; the other one of the high level signal and the low level signal is used for controlling the internal circulation subsystem to be closed and controlling the fresh air subsystem to supply air; and the wind mixing mode disabling instruction is used for controlling the internal circulation subsystem and the fresh air subsystem to be closed.

The high-level signal is used for controlling the air supply of the internal circulation subsystem and controlling the closing of the fresh air subsystem; the low level signal is used to control both the new air subsystem and the internal circulation subsystem to be turned off, for example, further description will be given, and the other situation is basically the same, which is not described herein again.

It should be noted that, in each period T, the signal is divided into four segments, as shown in fig. 2, the signal transmitting unit transmits the PWM signal, when V is_ctrlWhen the signal jumps (changes from high level to low level or from low level to high level), certain dead time is inserted, and the air conditioning system exhausts the residual air in the previous stage by utilizing the dead time.

As shown in fig. 4, when the high level signal duration t of the PWM signal is determined_onDuration t of low level signal_offDetermining the dead time t of the PWM signal_dead。

Starting a timer of duration t_onOutput a high level signal such that at time t_onThe internal circulation subsystem supplies air, the fresh air subsystem is closed, so that cold air of the internal circulation subsystem is blown into the air mixing area 45 and is sent into the room through the indoor air supply outlet 33 under the driving of the air supply fan 41, and the indoor temperature is adjusted.

When the high level signal continues to output for a time t_onThen, a mixed wind mode disabling instruction is sent out and the dead time t lasts_deadAt this time, the new air subsystem and the internal circulation subsystem are both closed, and the air supply fan 41 draws out the cold air remaining in the air mixing area 45 and supplies the cold air into the room through the indoor air supply outlet 33.

When mixingWind mode disable command duration output time t_deadThen, start the timer for a time t_offOutput a low level signal such that at time t_offThe internal circulation subsystem is closed, the fresh air subsystem supplies air, and the duration time is t_offThe fresh air is blown into the air mixing area 45 and is sent into the room through the indoor air supply outlet 33 under the driving of the air supply fan 41, so that the fresh air is sent in. It should be noted that, in the related art, when the internal circulation air supply is switched to the fresh air supply, condensation is easily generated in the air mixing area 45 because the temperature of the fresh air is higher than that of the cold air; according to the technical scheme, because the cold air in the high-level signal period is basically pumped away in the dead time, the cold air and the hot air cannot be mixed in the air mixing area 45, and therefore condensation generated in the stage is eliminated.

When the low level signal continues to output for a time t_offThen, a mixed wind mode disabling instruction is sent out and the dead time t lasts_deadAt this time, the fresh air subsystem and the internal circulation subsystem are both closed, and the air supply fan 41 draws away the residual hot air (the fresh air has a higher temperature than that in the internal circulation mode) in the air mixing area 45 and supplies the hot air into the room through the indoor air supply opening 33.

In the next cycle, a timer is started for a time period t_onAnd a high level signal is output, the internal circulation subsystem supplies air, and the fresh air subsystem is closed, so that cold air of the internal circulation subsystem is blown into the air mixing area 45 and is sent into the room through the indoor air supply outlet 33 under the driving of the air supply fan 41, and the indoor temperature is adjusted. Since the hot air (fresh air) during the last period of the low level signal is basically drawn away during the dead time, mixing of the cold and hot air does not occur in the air mixing region 45, thereby eliminating the condensation generated at this stage.

In some embodiments, the step S100 of determining the high-level signal duration and the low-level signal duration of the PWM signal includes steps S110 to S130.

And step S110, determining the duty ratio D of the PWM signal. Step S110, determining the duty ratio of the PWM signal, includes: step S111 and step S112.

S111, acquiring set temperature of the air conditioning system, collected ambient temperature and collected temperature of the heat exchanger 44, wherein the set temperature t_setTemperature set for user, or target temperature in air conditioner automatic mode, ambient temperature t_outsThe outdoor temperature can be collected by a temperature sensor arranged outside the building, and the temperature of the heat exchanger 44 can be collected by a temperature sensor arranged in the indoor heat exchanger 44.

And S112, determining the duty ratio D based on the set temperature, the ambient temperature and the temperature of the heat exchanger 44.

Wherein the set temperature and the ambient temperature are used to determine the absolute value of the temperature difference t_outs-t_set|。

Step S112, determining the duty ratio based on the set temperature, the ambient temperature and the temperature of the heat exchanger 44, includes: based on the temperature of the heat exchanger 44 and the first safety temperature T_{PROTECT_POINT}And a second safety temperature T_{CRITICAL_POINT}And absolute value of temperature difference | t_outs-t_setAnd determining the duty ratio D according to the comparison result of the | and the preset temperature difference value Delta T.

In other words, the duty ratio is adjustable, so that the method for adjusting the duty ratio can not only realize the supercooling protection of the heat exchanger 44, but also ensure that the temperature adjusting efficiency of the air conditioning system is high enough.

In actual implementation, the step S112 of determining the duty ratio based on the set temperature, the ambient temperature and the temperature of the heat exchanger 44 includes:

determining t_p≤T_{CRITICAL_POINT}Setting D to be 1;

determination of T_{CRITICAL_POINT}＜t_p＜T_{PROTECT_POINT}，|t_outs-t_setIf | ≧ Δ T, D is set to 0.7 ≦ D <1；

Determination of T_{CRITICAL_POINT}＜t_p＜T_{PROTECT_POINT}，|t_outs-t_setIf | <DELTAT, D is set to be more than 0.5 and less than 0.7;

determining t_p≥T_{PROTECT_POINT}，|t_outs-t_set| > delta T, and D is set to be more than 0.3 and less than or equal to 0.5;

determining t_p≥T_{PROTECT_POINT}，|t_outs-t_setDelta T is smaller than | and D is more than 0 and less than or equal to 0.3; wherein

T_{PROTECT_POINT}Is a first safety temperature, T_{CRITICAL_POINT}Is the second safety temperature, t_pIs the temperature, t, of the heat exchanger 44_setTo set the temperature, t_outsThe temperature is the ambient temperature, D is the duty ratio and is the preset value of the delta T temperature difference.

In one embodiment, the duty cycle D value may be adjusted in the manner shown in Table 1.

TABLE 1 Duty ratio determination Table

Step S120, determining high-level signal duration T based on period T and determined duty ratio D_onAs shown in fig. 2, the duty ratio D ═ t_onT, i.e. T_on＝D*T。

Step S130, determining the low-level signal duration T based on the period T and the determined duty ratio_offAs shown in fig. 2, the duty ratio D ═ t_onT, i.e. T_off＝(1-D)*T。

The method can conveniently determine the high-level signal duration t by determining the duty ratio according to the measured parameters_onAnd a low level signal duration t_off。

In some embodiments, the high level signal and the low level signal are used for controlling the opening and closing of air valves of the internal circulation subsystem and the fresh air subsystem.

As shown in fig. 1, the internal circulation subsystem includes a temperature-controlled air valve 11, the fresh air subsystem includes a fresh air valve 13, and the air mixing control method includes: determining that a high level signal is received, controlling the temperature control air valve 11 to be opened, and controlling the fresh air valve 13 to be closed; determining that a dead zone signal is received, and controlling the temperature control air valve 11 and the fresh air valve 13 to be closed; and determining that a low level signal is received, controlling the temperature control air valve 11 to be closed, and controlling the fresh air valve 13 to be opened.

In other words, in the above embodiment, the control of the air supply of the fresh air subsystem includes the control of the opening of the fresh air valve 13; controlling the fresh air subsystem to be closed, including controlling a fresh air valve 13 to be closed; controlling the air supply of the internal circulation subsystem, including controlling the opening of a temperature control air valve 11; and controlling the internal circulation subsystem to be closed, including controlling the temperature control air valve 11 to be closed.

Therefore, condensation prevention in the air mixing mode can be achieved by simply controlling the opening and closing of the air valve, the compressor, the fan and other equipment do not need to be started back and forth, the air mixing control method is more flexible, and equipment can be prevented from being damaged.

The "determining the dead time of the PWM signal" in the above step S100 includes: air flow F of air supply fan 41 based on air conditioning system_sDetermining dead time t by air duct coefficient K of indoor unit of air conditioning system, volume of indoor unit of air conditioner, flow cross-sectional area S of air supply fan 41 and response time delta t of air valve_dead. The air duct coefficient K is the proportion of the volume of an air duct in an indoor unit of the air conditioning system to the volume of the indoor unit. For example, for a 1.5P air conditioning system, in the fresh air mode, K is 0.83; in the internal circulation mode, K is 0.51.

Thus, the inventors of the present application found through a large number of experiments that the dead time t is_deadShort, the air in the previous stage cannot be exhausted cleanly, and condensation is caused; if the dead time is long, the negative pressure caused by the fan in the dead time is large, and the noise and the energy consumption are increased. The determination of the dead time t_deadThe method can determine the proper dead time t according to the specific design parameters of the air conditioning system_deadThe air in the last stage can be discharged completely, condensation is prevented, the influence of the negative pressure of the fan on the whole air conditioning system caused by closing of the air valve in the dead time is reduced as much as possible, and noise and energy consumption are reduced.

Air flow F of air supply fan 41 based on air conditioning system_sDetermining dead time t by air channel coefficient K of indoor unit of air conditioning system, volume V of indoor unit, flow cross-sectional area S of air supply fan 41 and response time delta t of air valve_deadInvolving the application of formulas

Determining dead time t_deadWherein

t_dead＝t_{dead theory}+Δt。

It can be understood that, since the air valve has a response time Δ t, in the initial stage of the actual dead time (within the time Δ t), the air valve is not completely closed, and when the air supply fan 41 extracts the residual air in the air mixing area 45, the internal circulation air or the fresh air is extracted in the same way as in the previous stage. The above determination can ensure that the residual air can be exhausted in the dead time by increasing the response time in the theoretical time.

In some embodiments, during the current cycle, if t_p≤T_{CRITICAL_POINT}The period T of the next period is shortened. T is_{CRITICAL_POINT}Is a preset second safety temperature, t_pIs the collected heat exchanger 44 temperature.

In other words, when cold protection occurs, it is indicated that the current period T is too long, resulting in too long a time (T) for the heat exchanger 44_off) No air heat exchange is carried out; by shortening the period T, the fresh air mode duration (T) in the next period can be shortened_off) Preventing overcooling of heat exchanger 44.

In some embodiments, the period T is determined based on the lives (the number of times of switching) of the first switch RY1 and the second switch RY2, the lives (the number of times of switching) of the thermo-valve 11 and the fresh air valve 13, the life of the air conditioner, and the cooling capacity of the air conditioner.

It is understood that the longer the life (number of times of switching) of the first switch and the second switch, and the longer the life (number of times of switching) of the thermo-valve 11 and the fresh air valve 13, the shorter period T may be set, and the stronger the cooling capability of the air conditioner, the shorter period T should be set to prevent the supercooling of the heat exchanger 44.

As shown in fig. 5, the control method of the air conditioning system includes: initializing a system, updating an operation mode, reading and writing an EEPROM (Electrically Erasable Programmable read only memory), judging the operation mode, if the wind mixing mode is determined to be entered, executing a wind mixing mode subprogram corresponding to the wind mixing control method until the wind mixing mode exits, and updating the operation mode again; if it is determined not to enter the wind mixing mode, the other sub-routine is entered.

In one embodiment, as shown in FIG. 6, a method of controlling a mix of air in an air conditioning system includes, as initiated; determining that the air supply fan 41 is closed, determining that the air exhaust fan 42 is closed, and determining that air valves are closed; initializing a timer; reading a set temperature, wherein the set temperature is the temperature set by a user; reading an ambient temperature, wherein the ambient temperature is measured by a temperature sensor; reading the temperature of the heat exchanger 44, wherein the temperature of the heat exchanger 44 is measured according to the temperature sensor; updating the duty cycle D based on the set temperature, the ambient temperature, and the temperature of the heat exchanger 44; setting t_onD x T, i.e. determining the duration T of the high-level signal on the basis of the duty cycle and the period T_on(ii) a Starting a timer; the PWM port outputs a high level signal until waiting for interruption; setting dead time t_dead(ii) a Outputting a mixed wind mode disabling instruction until waiting for interruption; sending out a mixed wind mode enabling instruction; setting t_off(1-D) T, i.e. determining the duration T of the low-level signal on the basis of the duty cycle and the period T_off(ii) a Starting a timer; the PWM port outputs a low level signal until waiting for interruption; setting dead time t_dead(ii) a And outputting a mixed wind mode disabling instruction, and finishing one period.

In some embodiments, as shown in fig. 7, the method for controlling mixed wind includes: obtaining the temperature t of the heat exchanger 44_pDetermining T is less than or equal to T_{CRITICAL_POINT}Setting D to be 1; after the delay deltaT, the temperature T of the heat exchanger 44 is obtained again_pDetermining t_p≤T_{CRITICAL_POINT}Sending out cold protection fault messageNumber, where the delay δ T is a predetermined time, T_{CRITICAL_POINT}Is a preset second safety temperature, t_pD is the duty cycle of the PWM signal for the collected heat exchanger 44 temperature.

A method of controlling the air-mixing of the air conditioning system according to another embodiment of the present application will be described with reference to fig. 1 to 7.

Wherein, air conditioning system includes: the air outlet of the fresh air subsystem and the air outlet of the fresh air subsystem are both communicated with the air supply outlet of the air conditioning system through the air mixing area 45 in some embodiments. The specific structure of the air conditioning system may refer to the description of the embodiments of the air conditioning system described above.

As shown in fig. 1 and 2, the air mixing control method according to the embodiment of the present application includes controlling the opening and closing of the fresh air subsystem and the internal circulation subsystem according to a periodic signal, where each period of the periodic signal includes a first segment of signal, a second segment of signal, a third segment of signal, and a fourth segment of signal, which are sequentially arranged in time.

As shown in FIG. 2, each period of the periodic signal is T, each period comprises a first segment signal, a second segment signal, a third segment signal and a fourth segment signal, and the duration of the first segment signal is T₁The second section of signal has duration t₂The third section signal has the duration of t₃The fourth signal has a duration t₄。

The air mixing control method of the embodiment of the application comprises the following steps: determining that one of the first section of signal and the third section of signal is received, controlling the internal circulation subsystem to supply air, and controlling the fresh air subsystem to be closed; determining that a second section of signal or a fourth section of signal is received, and controlling the new air subsystem and the internal circulation subsystem to be closed; and determining that the other one of the first section of signal and the third section of signal is received, controlling the internal circulation subsystem to be closed, and controlling the fresh air subsystem to supply air.

Then, determining that the first section of signal is received, controlling the internal circulation subsystem to supply air, and controlling the fresh air subsystem to be closed; determining that a second section of signals are received, and controlling the new air subsystem and the internal circulation subsystem to be closed; determining that a third section of signal is received, controlling the internal circulation subsystem to be closed, and controlling the fresh air subsystem to supply air; and determining that the fourth section of signal is received, and controlling the new air subsystem and the internal circulation subsystem to be closed, for example, the other situation is basically the same, and details are not repeated here.

As shown in fig. 2, the signal transmitting unit transmits a periodic signal.

When receiving the first section signal, the internal circulation subsystem supplies air, and the fresh air subsystem is closed, so that the cold air of the internal circulation subsystem is blown into the air mixing area 45 and is sent into the room through the indoor air supply outlet 33 under the driving of the air supply fan 41, and the indoor temperature is adjusted.

When the second section of signals are received, the new air subsystem and the internal circulation subsystem are both closed, and the air supply fan 41 draws out the residual cold air in the air mixing area 45 and supplies the cold air into the room through the indoor air supply outlet 33.

When the third section signal is received, the internal circulation subsystem is closed, the fresh air subsystem supplies air, the fresh air is blown into the air mixing area 45 and is sent into the room through the indoor air supply outlet 33 under the driving of the air supply fan 41, and therefore the fresh air is sent into the room. It should be noted that, in the related art, when the internal circulation air supply is switched to the fresh air supply, condensation is easily generated in the air mixing area 45 because the temperature of the fresh air is higher than that of the cold air; according to the technical scheme, because the cold air in the first section of signal period is basically pumped away in the second section of signal period, the mixing of the cold air and the hot air can not occur in the air mixing area 45, and therefore condensation generated in the stage is eliminated.

When the fourth section of signal is received, the new air subsystem and the internal circulation subsystem are both closed, and the air supply fan 41 draws away the residual hot air (the temperature of the new air is higher than that of the new air in the internal circulation mode) in the air mixing area 45 and sends the hot air into the room through the indoor air supply outlet 33.

In the next period, when the first section of signal is received, the internal circulation subsystem supplies air, and the fresh air subsystem is closed, so that the cold air of the internal circulation subsystem is blown into the air mixing area 45 and is sent into the room through the indoor air supply outlet 33 under the driving of the air supply fan 41, and the indoor temperature adjustment is realized. Since the hot air (fresh air) in the third signal period of the previous period is basically pumped away in the fourth signal period, the mixing of the hot air and the cold air does not occur in the air mixing area 45, thereby eliminating the condensation generated in the period.

In the above description of the embodiment, the air supply fan 41 is used to draw the air remaining in the air mixing area 45, but it is needless to say that an independent drawing fan may be provided, and the drawing fan is connected to the air mixing area 45 and is turned on to draw the air remaining in the air mixing area when the second-stage signal and the fourth-stage signal are applied.

According to the air mixing control method of the air conditioning system, the fresh air subsystem and the internal circulation subsystem are controlled to be opened and closed alternately by setting the periodic signal, air is not supplied to the two subsystems in alternation, breathing type air mixing is achieved, condensation in an air mixing mode can be eliminated fundamentally, and use experience of the air conditioning system is improved.

In some embodiments, as shown in fig. 2, the periodic signal is a PWM (pulse width modulation) signal, the first segment signal is a high level signal, the second segment signal and the fourth segment signal are dead time, and the third segment signal is a low level signal.

Correspondingly, the air mixing control method comprises the following steps: determining to receive one of a high level signal and a low level signal, controlling the air supply of the internal circulation subsystem, and controlling the closing of the fresh air subsystem; determining that the other one of the high level signal and the low level signal is received, controlling the internal circulation subsystem to be closed, and controlling the fresh air subsystem to supply air; and in the dead time, the fresh air subsystem and the internal circulation subsystem are controlled to be closed.

It should be noted that the PWM signal can accurately and conveniently realize the above-mentioned periodic control, and the PWM signal used in the embodiment of the present application includes two dead time periods in each period.

The signal transmitting unit transmits a PWM signal when V_ctrlWhen the signal jumps (changes from high level to low level or from low level to high level), certain dead time is inserted, and the dead time is used to exhaust the residual air in the previous stage.

At the received V_ctrlWhen the signal is a high level signalAir is supplied by the internal circulation subsystem, the fresh air subsystem is closed, and the duration time is t_onThus, the cold air of the internal circulation subsystem is blown into the air mixing area 45 and is sent into the room through the indoor air supply outlet 33 under the driving of the air supply fan 41, thereby realizing the indoor temperature adjustment.

When the dead time is received, the new air subsystem and the internal circulation subsystem are both closed, and the duration is t_deadThe blower fan 41 draws out the cold air remaining in the air mixing area 45 and sends the cold air into the room through the indoor air supply outlet 33.

At the received V_ctrlWhen the signal is a low level signal, the internal circulation subsystem is closed, the fresh air subsystem supplies air, and the duration time is t_offThe fresh air is blown into the air mixing area 45 and is sent into the room through the indoor air supply outlet 33 under the driving of the air supply fan 41, so that the fresh air is sent in. It should be noted that, in the related art, when the internal circulation air supply is switched to the fresh air supply, condensation is easily generated in the air mixing area 45 because the temperature of the fresh air is higher than that of the cold air; according to the technical scheme, because the cold air in the high-level signal period is basically pumped away in the dead time, the cold air and the hot air cannot be mixed in the air mixing area 45, and therefore condensation generated in the stage is eliminated.

When the dead time is received, the new air subsystem and the internal circulation subsystem are both closed, and the duration is t_deadThe air blower 41 draws out the hot air remaining in the air mixing region 45 (the fresh air has a higher temperature than the energy generation temperature in the internal circulation mode), and sends the hot air into the room through the indoor air outlet 33.

In the next period, when a high level signal is received, the internal circulation subsystem supplies air, and the fresh air subsystem is closed, so that cold air of the internal circulation subsystem is blown into the air mixing area 45 and is sent into the room through the indoor air supply outlet 33 under the driving of the air supply fan 41, and the indoor temperature is adjusted. Since the hot air (fresh air) during the last period of the low level signal is basically drawn away during the dead time, mixing of the cold and hot air does not occur in the air mixing region 45, thereby eliminating the condensation generated at this stage.

In some embodiments, each second segment signal is equal in duration to each fourth segment signal. Therefore, the time modulation of each period is simple, and the control is convenient to realize.

In some embodiments, the air conditioning system further comprises: the air mixing area 45 and the air supply fan 41, the air outlets of the new air subsystem and the internal circulation subsystem are communicated with the indoor air supply outlet 33 of the air conditioning system through the air mixing area 45, and the air supply fan 41 is used for driving the air in the air mixing area 45 to be discharged to the indoor air supply outlet 33; the air mixing control method comprises the following steps: during the second segment signal period and the fourth segment signal period, the blower fan 41 is controlled to be turned on.

Thus, the air supply fan 41 can pump the air remained in the air mixing area 45 in the previous stage in the dead time between the inner circulation work and the fresh air work, and an independent air exhaust fan is not arranged, so that the number of parts of the air conditioning system can be reduced, and the control difficulty is reduced.

As shown in fig. 1, the internal circulation subsystem includes a temperature-controlled air valve 11, the fresh air subsystem includes a fresh air valve 13, and the air mixing control method includes: determining that one of the first section signal and the third section signal is received, controlling the temperature control air valve 11 to be opened, and controlling the fresh air valve 13 to be closed; determining that the second section of signal or the fourth section of signal is received, and controlling the temperature control air valve 11 and the fresh air valve 13 to be closed; and determining that the other one of the first section signal and the third section signal is received, controlling the temperature control air valve 11 to be closed, and controlling the fresh air valve 13 to be opened.

In other words, in the above-described embodiment: controlling the air supply of the fresh air subsystem, including controlling the opening of a fresh air valve 13; controlling the fresh air subsystem to be closed, including controlling a fresh air valve 13 to be closed; controlling the air supply of the internal circulation subsystem, including controlling the opening of a temperature control air valve 11; and controlling the internal circulation subsystem to be closed, including controlling the temperature control air valve 11 to be closed.

In some embodiments, the method of controlling the mixing of air comprises: at t_p＜T_{PROTECT_POINT}Time of day, adjust periodic messageNumber t to₁/t₃＞F_PP/F_{IN_CIRCLE}Wherein, t_pFor the received heat exchanger 44 temperature, T, of the internal circulation sub-system_{PROTECT_POINT}Is a first safety temperature, F_{IN_CIRCLE}For the internal circulation flow during the supply of air to the internal circulation sub-system, F_PPThe fresh air flow, t, when the fresh air subsystem is supplied with air₁For the duration, t, of the first segment signal in each cycle₃The duration of the third segment signal in each period.

It will be appreciated that the heat exchanger temperature t_pCan be measured by a temperature sensor, the first safety temperature T_{PROTECT_POINT}The preset value is the internal circulation flow F when the internal circulation subsystem supplies air_{IN_CIRCLE}Fresh air flow F in air supply of fresh air subsystem_PPThen, according to the type of the supply fan 41 and the rotation speed of the supply fan 41 in each stage, when the rotation speeds of the supply fan 41 in the fresh air and internal circulation stages are the same, F is determined_PP/F _{IN_CIRCLE}1, i.e. t₁＞t₃。

With the above arrangement, when the temperature of the heat exchanger 44 is relatively low, t can be increased₁/t₃The ratio of (2) increases the air volume of the internal circulation and protects the heat exchanger 44.

When the periodic signal is a PWM signal, the mixed air control method comprises the following steps: at t_p＜T_{PROTECT_POINT}The periodic signal is adjusted so that t_on/t_off＞F_PP/F_{IN_CIRCLE}Wherein, t_pFor the received heat exchanger 44 temperature, T, of the internal circulation sub-system_{PROTECT_POINT}Is a first safety temperature, F_{IN_CIRCLE}For the internal circulation flow during the supply of air to the internal circulation sub-system, F_PPThe fresh air flow, t, when the fresh air subsystem is supplied with air_onFor the duration, t, of the first segment signal in each cycle_offThe duration of the third segment signal in each period.

t_on/t_offD is the duty ratio of the PWM signal, that is, the duty ratio of the PWM signal of the embodiment of the present application is adjustable, and when the rotation speeds of the air supply fan 41 in the fresh air and the internal circulation stage are the same, the duty ratio of the PWM signal is adjustable，F_PP/F _{IN_CIRCLE}1, even if D > 0.5.

In some embodiments, the method of controlling the mixing of wind comprises: at T_{CRITICAL_POINT}＜t_p＜T_{PROTECT_POINT}The periodic signal is adjusted so that t₁/t₃＞F_PP/F_{IN_CIRCLE}(ii) a At t_p≤T_{CRITICAL_POINT}Sending a cold protection fault signal; wherein, t_pTo receive the heat exchanger 44 temperature, T, of the internal circulation subsystem_{PROTECT_POINT}Is a first safety temperature, T_{CRITICAL_POINT}Is a second safety temperature, F_{IN_CIRCLE}For the internal circulation flow during the supply of air to the internal circulation sub-system, F_PPThe fresh air flow, t, when the fresh air subsystem is supplied with air₁For the duration, t, of the first segment signal in each cycle₃The duration of the third segment signal in each period.

It will be appreciated that the heat exchanger 44 temperature t_pCan be measured by a temperature sensor, the first safety temperature T_{PROTECT_POINT}And a second safety temperature T_{CRITICAL_POINT}Is a predetermined value, T_{CRITICAL_POINT}＜T_{PROTECT_POINT}Internal circulation flow F during air supply of internal circulation subsystem_{IN_CIRCLE}Fresh air flow F in air supply of fresh air subsystem_PPThen, according to the type of the supply fan 41 and the rotation speed of the supply fan 41 in each stage, when the rotation speeds of the supply fan 41 in the fresh air and internal circulation stages are the same, F is determined_PP/F _{IN_CIRCLE}1, i.e. t₁＞t₃。

With the above arrangement, when the temperature of the heat exchanger 44 is relatively low, t can be increased₁/t₃The ratio of (2) increases the air volume of the internal circulation and protects the heat exchanger 44; when the temperature of the heat exchanger 44 is too low, it is indicated that the periodic signal is "adjusted so that t₁/t₃＞F_PP/F_{IN_CIRCLE}"control failure" sends a cold protection fault signal to the outer machine electronic control board to prevent damage to the heat exchanger 44.

When the periodic signal is a PWM signal, the mixed air control method comprises the following steps: at T_{CRITICAL_POINT}＜t＜T_{PROTECT_POINT}The periodic signal is adjusted so that t_on/t_off＞F_PP/F_{IN_CIRCLE}Where T is the received heat exchanger 44 temperature of the internal circulation sub-system, T_{PROTECT_POINT}Is a first safety temperature, F_{IN_CIRCLE}For the internal circulation flow during the supply of air to the internal circulation sub-system, F_PPThe fresh air flow, t, when the fresh air subsystem is supplied with air_onFor the duration, t, of the first segment signal in each cycle_offThe duration of the third segment signal in each period.

t_on/t_offD is the duty cycle of the PWM signal, that is, the duty cycle of the PWM signal of the embodiment of the present application is adjustable. Through the arrangement, when the temperature of the heat exchanger 44 is lower, the air quantity of the internal circulation can be increased by increasing the duty ratio D, the heat exchanger 44 is protected, and when the rotating speeds of the air supply fan 41 in the fresh air and the internal circulation stage are the same, F_PP/F _{IN_CIRCLE}1, even if D > 0.5; when the temperature of the heat exchanger 44 is too low, it is indicated that the periodic signal is "adjusted so that t₁/t₃＞F_PP/F_{IN_CIRCLE}"control failure" sends a cold protection fault signal to the outer machine electronic control board to prevent damage to the heat exchanger 44.

The control circuit of the embodiment of the present application, which is used for implementing the above-mentioned wind mixing control method on hardware, is described below with reference to fig. 3.

As shown in fig. 3, the control circuit includes: the signal driving sub-circuit 51, the dead zone inserting sub-circuit 52, the first switch RY1, and the second switch RY 2.

The first switch RY1 is electrically connected with the fresh air subsystem, and the first switch RY1 is used for controlling the working state of the fresh air subsystem; the second switch RY2 is electrically connected with the internal circulation subsystem, and the second switch RY2 is used for controlling the working state of the internal circulation subsystem.

The input end of the signal driving sub-circuit 51 is used for receiving the PWM signal, for example, the input end of the signal driving sub-circuit 51 is used for receiving an IO port of a single chip microcomputer, and the PWM signal is generated by a timer. The signal driving sub-circuit 51 is configured to output a signal having the same phase as or the opposite phase of the incoming signal at a first output terminal and a second output terminal, respectively.

That is, the signal driving sub-circuit 51 can convert the same signal into two signals with opposite phases, and output the two signals from the first output terminal and the second output terminal respectively. The dead-band insertion sub-circuit 52 is electrically connected to the second control port K12 of the first switch RY1 and the second control port K22 of the second switch RY 2.

The first control port K11 of the first switch RY1 is electrically connected with the first output end of the signal driving sub-circuit 51, the first control port K11 of the first switch RY1 is used for accessing a signal output by the first output end, and the first switch RY1 switches the opening and closing state of the first switch RY1 according to the signal accessed by the first control port K11 of the first switch RY1, so that the working state of the fresh air subsystem is controlled. The first switch RY1 also switches the open-close state of the first switch RY1 according to the signal accessed from the second control port K12, thereby controlling the working state of the fresh air subsystem.

The first switch RY1 is arranged such that the control logic corresponding to the first control port K11 of the first switch RY1 and the control logic corresponding to the second control port K12 of the first switch RY1 are connected in series.

In other words, when the control logic corresponding to the first control port K11 of the first switch RY1 is to close the first switch RY1, and the control logic corresponding to the second control port K12 of the first switch RY1 is to close the first switch RY1, the first switch RY1 is closed; when the control logic corresponding to the first control port K11 of the first switch RY1 is to close the first switch RY1 and the control logic corresponding to the second control port K12 of the first switch RY1 is to open the first switch RY1, the first switch RY1 is opened; when the control logic corresponding to the first control port K11 of the first switch RY1 is to turn off the first switch RY1 and the control logic corresponding to the second control port K12 of the first switch RY1 is to turn off the first switch RY1, the first switch RY1 is turned off; when the control logic corresponding to first control port K11 of first switch RY1 is to open first switch RY1 and the control logic corresponding to second control port K12 of first switch RY1 is to close first switch RY1, first switch RY1 is opened.

The first control port K21 of the second switch RY2 is electrically connected with the second output end of the signal driving sub-circuit 51, the first control port K21 of the second switch RY2 is used for accessing signals output by the second output end, and the second switch RY2 switches the opening and closing state of the second switch RY2 according to the signals accessed by the first control port K21 of the second switch RY2, so that the working state of the internal circulation sub-system is controlled. The second switch RY2 also switches the on-off state of the second switch RY2 according to the signal accessed from the second control port K22, thereby controlling the working state of the internal circulation subsystem.

The second switch RY2 is provided such that the control logic corresponding to the first control port K21 of the second switch RY2 and the control logic corresponding to the second control port K22 of the second switch RY2 are connected in series.

In other words, when the control logic corresponding to first control port K21 of second switch RY2 is to close second switch RY2, and the control logic corresponding to second control port K22 of second switch RY2 is to close second switch RY2, second switch RY2 is closed; when the control logic corresponding to the first control port K21 of the second switch RY2 is to close the second switch RY2 and the control logic corresponding to the second control port K22 of the second switch RY2 is to open the second switch RY2, the second switch RY2 is opened; when the control logic corresponding to first control port K21 of second switch RY2 is to turn off second switch RY2 and the control logic corresponding to second control port K22 of second switch RY2 is to turn off second switch RY2, second switch RY2 is turned off; when the control logic corresponding to first control port K21 of second switch RY2 is to open second switch RY2 and the control logic corresponding to second control port K22 of second switch RY2 is to close second switch RY2, second switch RY2 is opened.

When the dead zone inserting sub-circuit 52 is connected with a high level signal, the first switch RY1 and the second switch RY2 are both disconnected, and correspondingly, the air is not supplied to the internal circulation sub-system and the fresh air sub-system; the mixed wind mode is enabled when the dead band insertion sub-circuit 52 switches in a low level signal.

When the dead zone insertion sub-circuit 52 receives a low-level signal and the PWM signal received at the input terminal of the signal driving sub-circuit 51 is at a high level, the first output terminal of the signal driving sub-circuit 51 outputs a high-level signal, the second output terminal of the signal driving sub-circuit 51 outputs a low-level signal, the first switch RY1 is opened, and the second switch RY2 is closed. When the control circuit is used for an air conditioning system, the fresh air subsystem does not supply air, and the internal circulation subsystem works to supply air. For example, the fresh air damper 13 may be closed, and the thermostatic damper 11 may be opened. Fresh air subsystem without blowing air

At the instant when the PWM signal changes from high to low, the dead-zone insertion sub-circuit 52 switches on high and delays for a period of time (t)_dead) At this time, both the first switch RY1 and the second switch RY2 are turned off, that is, a dead zone is inserted. When the control circuit is used for an air conditioning system, the fresh air subsystem does not supply air, and the internal circulation subsystem does not supply air. For example, both the thermo-valve 11 and the fresh air valve 13 may be closed.

When the dead zone is over, when the PWM signal connected to the input terminal of the signal driving sub-circuit 51 is at low level, the first output terminal of the signal driving sub-circuit 51 outputs a low level signal, the second output terminal of the signal driving sub-circuit 51 outputs a high level signal, the first switch RY1 is closed, and the second switch RY2 is opened. When the control circuit is used for an air conditioning system, the fresh air subsystem works to supply air, and the internal circulation subsystem does not supply air. For example, the fresh air damper 13 may be opened and the thermostatic damper 11 may be closed.

At the instant when the PWM signal changes from low to high, the dead-zone insertion sub-circuit 52 switches on high and delays for a period of time (t)_dead) At this time, both the first switch RY1 and the second switch RY2 are turned off, that is, a dead zone is inserted. When the control circuit is used for an air conditioning system, the fresh air subsystem does not supply air, and the internal circulation subsystem does not supply air. For example, both the thermo-valve 11 and the fresh air valve 13 may be closed.

The control circuit of the embodiment of the application divides the PWM signal into two opposite paths through the signal driving sub-circuit, can realize the alternate opening and closing of the two controlled parts, and inserts the dead zone through the dead zone inserting sub-circuit, so that the two controlled parts can also insert the dead zone time during the alternate opening and closing.

When the control circuit is used for controlling the working states of the internal circulation subsystem and the fresh air subsystem of the air conditioning system, the air mixing mode can be conveniently and accurately realized, condensation in the air mixing mode can be fundamentally eliminated, and the use experience of the air conditioning system is improved.

In some embodiments, the second control port K12 of the first switch RY1 and the second control port K22 of the second switch RY2 are used to access the switching power supply. As shown in fig. 3, the second control port K12 of the first switch RY1 and the second control port K22 of the second switch RY2 are used to access the switching power supply +12V, and the power supply port is also accessed to the current limiting resistor R24 for current limiting.

The dead zone insertion sub-circuit 52 is provided to cut off the power supply to the second control port K12 of the first switch RY1 and the second control port K22 of the second switch RY2 when a high level signal is turned on; the dead-zone insertion sub-circuit 52 is provided to turn on the power supply of the second control port K12 of the first switch RY1 and the second control port K22 of the second switch RY2 when a low level signal is turned on.

In some embodiments, as shown in fig. 3, the dead-zone insertion sub-circuit 52 includes a transistor V1, a base B of the transistor V1 is used for receiving high and low level signals, an emitter E of the transistor V1 is used for grounding, and a collector C of the transistor V1 is electrically connected to the second control port K12 of the first switch RY1 and the second control port K22 of the second switch RY 2.

As shown in fig. 3, the dead-band insertion sub-circuit 52 includes a first filter circuit electrically connected to the base of transistor V1. The first filter circuit may include a resistor R11 and a capacitor C11 connected in parallel, one end of the resistor R11 and one end of the capacitor C11 connected in parallel being connected to the base B of the transistor V1, and the other end of the resistor R11 and the other end of the capacitor C11 connected in parallel being grounded. The first filter circuit is used for filtering. The input terminal MODE _ ENABLE of the dead band insertion sub-circuit 52 may also be coupled to a current limiting resistor R21 for current limiting.

In some embodiments, as shown in fig. 3, the signal driving sub-circuit 51 includes: the input end of the signal driving sub-circuit 51 comprises a base B of the inverting triode V2 and a first input port 1B of the relay driving chip IC1, an emitter E of the inverting triode V2 is used for grounding, and a collector C of the inverting triode V2 is electrically connected with a second input port 2B of the relay driving chip IC 1; a first output terminal of the signal driving sub-circuit 51 includes the first output port 1C of the relay driving chip IC1, and a second output terminal of the signal driving sub-circuit 51 includes the second output port 2C of the relay driving chip IC 1.

By arranging the inverting triode V2, the access signals of the first input port 1B and the second input port 2B of the relay driver chip IC1 are inverted, the level signal of the first output port 1C of the relay driver chip IC1 corresponds to the level signal of the first input port 1B of the relay driver chip IC1, and the level signal of the second output port 2C of the relay driver chip IC1 corresponds to the level signal of the second input port 2B of the relay driver chip IC1, so that the first output end and the second output end of the signal driver sub-circuit 51 can output inverted signals.

In some embodiments, as shown in fig. 3, the second input port 2B of the relay driver IC1 is further connected to a power supply +3V, and a current limiting resistor R25 is connected between the power supply and the second input port 2B for limiting current.

The capacitor C14 is connected between the G port and the V port of the relay driving chip IC1, the G port of the relay driving chip IC1 is grounded, and the V port of the relay driving chip IC1 is connected with a +12V power supply.

In some embodiments, as shown in fig. 3, the signal driving sub-circuit 51 further includes: and the second filter circuit is electrically connected with the base B of the inverting triode V2. The second filter circuit may include a resistor R12 and a capacitor C12 connected in parallel, one end of the resistor R12 and one end of the capacitor C12 connected in parallel are connected to the base B of the inverting transistor V2, and the other end of the resistor R12 and the other end of the capacitor C12 connected in parallel are grounded. The second filter circuit is used for filtering. The base B of the inverting triode V2 can be connected with a current-limiting resistor R22 to limit current.

In some embodiments, as shown in fig. 3, the signal driving sub-circuit 51 further includes: and a third filter circuit electrically connected to the second input port 2B of the relay driver IC 1. The third filter circuit may include a resistor R13 and a capacitor C13 connected in parallel, one end of the resistor R13 and the capacitor C13 connected in parallel being connected to the first input port 1B of the relay driver chip IC1, and the other end of the resistor R13 and the capacitor C13 connected in parallel being grounded. The third filter circuit is used for filtering. The first input port 1B of the relay driver IC1 may also be connected to a current limiting resistor R23 for limiting current.

In some embodiments, as shown in fig. 3, the first switch RY1 may be a five-wire relay, the first control port K11 of the first switch RY1 is connected to the first output port 1C of the relay driver IC1, the second control port K12 of the first switch RY1 is connected to the switching power supply +12V and the collector C of the triode V1, the live wire access port K13 of the first switch RY1 is connected to the live wire of the power supply, the live wire control port K15 of the first switch RY1 is connected to the first device to be controlled, such as the fresh air valve 13 of the fresh air subsystem, and the other port K14 of the first switch RY1 is connected to the air.

The second switch RY2 can be a five-wire relay, the first control port K21 of the second switch RY2 is connected to the second output port 2C of the relay driving chip IC1, the second control port K22 of the second switch RY2 is connected to the switching power supply +12V and the collector C of the triode V1, the live wire access port K23 of the second switch RY2 is connected to the live wire of the power supply, the live wire control port K25 of the second switch RY2 is connected to the second device to be controlled, such as the thermo-valve 11 of the internal circulation subsystem, and the other port K24 of the second switch RY2 is connected in an air-connected mode.

As shown in fig. 3, the control circuit has terminals CN1 and CN2, a first interface of the terminal CN1 is connected to the live control port K15 of the first switch RY1, and a second interface of the terminal CN1 is connected to the neutral line; the first interface of the terminal CN2 is connected with the live wire control port K25 of the second switch RY2, and the second interface of the terminal CN2 is connected with the zero wire.

When the control circuit is used for an air conditioning system, a first interface of a live wire connecting terminal CN1 of the temperature control air valve 11 and a second interface of a zero wire connecting terminal CN1 of the temperature control air valve 11 are connected; the live wire of new trend blast gate 13 connects the first interface of terminal CN2, and the zero line of new trend blast gate 13 connects the second interface of terminal CN 2.

The application also discloses a control chip.

The control chip comprises a control circuit and a single chip microcomputer, wherein an IO interface of the single chip microcomputer is electrically connected with an input end of the signal driving sub-circuit 51 and an input end of the dead zone inserting sub-circuit 52. The control chip can generate PWM signals with adjustable duty ratios through the timer.

The application also discloses an air conditioning system.

As shown in fig. 1 to 3, the air conditioning system includes: fresh air subsystem, inner loop subsystem and control chip, control chip are the control chip of above-mentioned one embodiment, and first switch RY1 is connected with fresh air subsystem electricity, and second switch RY2 is connected with inner loop subsystem electricity.

As shown in fig. 1 to 3, the air conditioning system includes: fresh air subsystem, inner loop subsystem and control chip, control chip are the control circuit of above-mentioned one embodiment, and first switch RY1 is connected with fresh air subsystem electricity, and second switch RY2 is connected with inner loop subsystem electricity.

As shown in figure 1, the fresh air subsystem is provided with a fresh air damper 13, the internal circulation subsystem is provided with a temperature control damper 11, the first switch RY1 is electrically connected with the fresh air damper 13, and the second switch RY2 is electrically connected with the temperature control damper 11.

As shown in fig. 1, the air conditioning system has an air mixing area 45, the temperature-controlled air valve 11 is used for controlling the communication state between the internal circulation subsystem and the air mixing area 45, and the fresh air valve 13 is used for controlling the communication state between the air suction port of the fresh air subsystem and the air mixing area 45. The air outlets of the fresh air subsystem and the internal circulation subsystem are communicated with the air outlet of the air conditioning system through an air mixing area 45.

According to the air conditioning system of this application embodiment, through the control circuit who sets up above-mentioned structural style, and control two subsystems and do not all supply air between in turn, realize the mixed wind of breathing formula, can fundamentally eliminate the condensation under the mixed wind mode, improve air conditioning system's use and experience.

The following describes the air mixing control device of the air conditioning system provided in the embodiments of the present application, and the air mixing control device of the air conditioning system described below and the air mixing control method of the air conditioning system described above may be referred to in correspondence with each other.

The air conditioning system includes: internal circulation subsystem and new trend subsystem, as shown in fig. 8, this mixed wind controlling means includes: a duration determination module 710, a timer 720, and a control module 730.

The duration determining module 710 is configured to determine a dead time of the PWM signal when determining a high level signal duration and a low level signal of the PWM signal; a timer 720; the control module 730 is configured to start the timer 720, and control the PWM port to output a high level signal according to the duration of the high level signal; sending out a mixed wind mode forbidding instruction; after the dead time, sending out a mixed wind mode enabling instruction; starting a timer 720, controlling the PWM port to output a low level signal according to the duration of the low level signal; sending out a mixed wind mode forbidding instruction; one of the high level signal and the low level signal is used for controlling the air supply of the internal circulation subsystem and controlling the closing of the fresh air subsystem; the other one of the high level signal and the low level signal is used for controlling the internal circulation subsystem to be closed and controlling the fresh air subsystem to supply air; and the wind mixing mode disabling instruction is used for controlling the internal circulation subsystem and the fresh air subsystem to be closed.

According to the air mixing control device of the air conditioning system, the high-low level signals are controlled and output in each period, dead time is inserted between the high-low level signals, so that air is not supplied to the two subsystems, the breathing type air mixing is realized, condensation in an air mixing mode can be fundamentally eliminated, and the use experience of the air conditioning system is improved.

As shown in fig. 1-8, the present application also discloses an air conditioning system comprising: an internal circulation subsystem, a fresh air subsystem and the air mixing control device of the embodiment.

According to the air conditioning system provided by the embodiment of the application, the fresh air subsystem and the internal circulation subsystem are controlled to be opened and closed alternately by setting the periodic signal, and the two subsystems are controlled to not supply air alternately, so that condensation in the air mixing mode can be eliminated fundamentally, and the use experience of the air conditioning system is improved.

Fig. 9 illustrates a physical structure diagram of an electronic device, and as shown in fig. 9, the electronic device may include: a processor (processor)810, a communication Interface 820, a memory 830 and a communication bus 840, wherein the processor 810, the communication Interface 820 and the memory 830 communicate with each other via the communication bus 840. The processor 810 may invoke logic instructions in the memory 830 to perform a method of controlling the aeration of an air conditioning system, the method comprising, in each cycle T, performing the steps of: determining the high level signal duration and the low level signal duration of the PWM signal, and determining the dead time of the PWM signal; starting a timer, and controlling a PWM (pulse width modulation) port to output a high level signal according to the duration of the high level signal; based on the dead time, sending out a mixed wind mode forbidding instruction; after the dead time, sending out a mixed wind mode enabling instruction; starting a timer, and controlling a PWM (pulse width modulation) port to output a low level signal according to the duration of the low level signal; based on the dead time, sending out a mixed wind mode forbidding instruction; one of the high level signal and the low level signal is used for controlling the air supply of the internal circulation subsystem and controlling the closing of the fresh air subsystem; the other one of the high level signal and the low level signal is used for controlling the internal circulation subsystem to be closed and controlling the fresh air subsystem to supply air; and the wind mixing mode disabling instruction is used for controlling the internal circulation subsystem and the fresh air subsystem to be closed.

It should be noted that, when being implemented specifically, the electronic device in this embodiment may be a server, a PC, or other devices, as long as the structure includes the processor 810, the communication interface 820, the memory 830, and the communication bus 840 shown in fig. 9, where the processor 810, the communication interface 820, and the memory 830 complete mutual communication through the communication bus 840, and the processor 810 may call the logic instructions in the memory 830 to execute the above method. The embodiment does not limit the specific implementation form of the electronic device.

In addition, the logic instructions in the memory 830 may be implemented in software functional units and stored in a computer readable storage medium when the logic instructions are sold or used as independent products. Based on such understanding, the technical solution of the present application or portions thereof that substantially contribute to the prior art may be embodied in the form of a software product stored in a storage medium and including instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.

Further, the present application discloses a computer program product, the computer program product includes a computer program stored on a non-transitory computer readable storage medium, the computer program includes program instructions, when the program instructions are executed by a computer, the computer can execute the air mixing control method of the air conditioning system provided by the above method embodiments, the air mixing control method includes, in each period T, executing the following steps: determining the high level signal duration and the low level signal duration of the PWM signal, and determining the dead time of the PWM signal; starting a timer, and controlling a PWM (pulse width modulation) port to output a high level signal according to the duration of the high level signal; based on the dead time, sending out a mixed wind mode forbidding instruction; after the dead time, sending out a mixed wind mode enabling instruction; starting a timer, and controlling a PWM (pulse width modulation) port to output a low level signal according to the duration of the low level signal; based on the dead time, sending out a mixed wind mode forbidding instruction; one of the high level signal and the low level signal is used for controlling the air supply of the internal circulation subsystem and controlling the closing of the fresh air subsystem; the other one of the high level signal and the low level signal is used for controlling the internal circulation subsystem to be closed and controlling the fresh air subsystem to supply air; and the wind mixing mode disabling instruction is used for controlling the internal circulation subsystem and the fresh air subsystem to be closed.

In another aspect, embodiments of the present application further provide a non-transitory computer-readable storage medium, on which a computer program is stored, where the computer program is implemented by a processor to execute the method for controlling mixed air of an air conditioning system provided in the foregoing embodiments, where the method for controlling mixed air includes, in each period T, performing the following steps: determining the high level signal duration and the low level signal duration of the PWM signal, and determining the dead time of the PWM signal; starting a timer, and controlling a PWM (pulse width modulation) port to output a high level signal according to the duration of the high level signal; based on the dead time, sending out a mixed wind mode forbidding instruction; after the dead time, sending out a mixed wind mode enabling instruction; starting a timer, and controlling a PWM (pulse width modulation) port to output a low level signal according to the duration of the low level signal; based on the dead time, sending out a mixed wind mode forbidding instruction; one of the high level signal and the low level signal is used for controlling the air supply of the internal circulation subsystem and controlling the closing of the fresh air subsystem; the other one of the high level signal and the low level signal is used for controlling the internal circulation subsystem to be closed and controlling the fresh air subsystem to supply air; and the wind mixing mode disabling instruction is used for controlling the internal circulation subsystem and the fresh air subsystem to be closed.

The above-described embodiments of the apparatus are merely illustrative, and the units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment. One of ordinary skill in the art can understand and implement it without inventive effort.

Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware. With this understanding in mind, the above-described technical solutions may be embodied in the form of a software product, which can be stored in a computer-readable storage medium such as ROM/RAM, magnetic disk, optical disk, etc., and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute the methods described in the embodiments or some parts of the embodiments.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions in the embodiments of the present application.

Claims

1. A method of controlling air mixing of an air conditioning system, the air conditioning system comprising: an internal circulation subsystem and a fresh air subsystem; the air mixing control method comprises the following steps of executing in each period T:

determining the high level signal duration and the low level signal duration of a PWM signal, and determining the dead time of the PWM signal;

starting a timer, and controlling a PWM (pulse width modulation) port to output a high level signal according to the duration of the high level signal;

based on the dead time, sending out a mixed wind mode forbidding instruction;

after the dead time, issuing a mixed wind mode enabling instruction;

starting a timer, and controlling a PWM (pulse width modulation) port to output a low level signal according to the duration of the low level signal;

based on the dead time, sending out a mixed wind mode forbidding instruction;

one of the high level signal and the low level signal is used for controlling the air supply of the internal circulation subsystem and controlling the closing of the fresh air subsystem; the other one of the high level signal and the low level signal is used for controlling the internal circulation subsystem to be closed and controlling the fresh air subsystem to supply air; and the mixed air mode forbidding instruction is used for controlling the internal circulation subsystem and the fresh air subsystem to be closed and controlling the air supply fan to extract air in the mixed air area so as to discharge the air into the room.

2. The air mixing control method of the air conditioning system according to claim 1, wherein the determining the high level signal duration and the low level signal duration of the PWM signal includes:

determining a duty cycle of the PWM signal;

determining a high level signal duration based on the period T and the determined duty cycle;

determining a low level signal duration based on the period T and the determined duty cycle.

3. The method of claim 2, wherein determining the duty cycle of the PWM signal comprises:

acquiring a set temperature, a collected ambient temperature and a collected heat exchanger temperature of the air conditioning system;

determining the duty cycle based on the set temperature, the ambient temperature, and the heat exchanger temperature.

4. The air mix control method of an air conditioning system according to claim 3, wherein the determining the duty ratio based on the set temperature, the ambient temperature, and the heat exchanger temperature includes:

determining t_p≤T_{CRITICAL_POINT}Setting D = 1;

determination of T_{CRITICAL_POINT}＜t_p＜T_{PROTECT_POINT}，|t_outs-t_set| > Δ T, and D is set to be more than or equal to 0.7 and less than 1;

determination of T_{CRITICAL_POINT}＜t_p＜T_{PROTECT_POINT}，|t_outs-t_setDelta T is smaller than | and D is set to be more than 0.5 and less than 0.7;

T_{PROTECT_POINT}Is a first safety temperature, T_{CRITICAL_POINT}Is the second safety temperature, t_pIs the temperature of the heat exchanger, t_setFor the set temperature, t_outsAnd D is the duty ratio and is a delta T temperature difference preset value.

5. The air mixing control method of the air conditioning system according to any one of claims 1 to 4, wherein the high level signal and the low level signal are used for controlling the opening and closing of air valves of the internal circulation subsystem and the fresh air subsystem;

the determining the dead time of the PWM signal includes:

air supply flow F of air supply fan based on air conditioning system_sAn air duct coefficient K of an indoor unit of the air conditioning system, a volume V of the indoor unit, a flow cross-sectional area S of the air supply fan, and a response time of the air valve

Determining said dead time t_dead。

6. The air mix control method of an air conditioning system according to claim 5, wherein the flow rate of air blown by the air blower of the air conditioning system is F_sAn air duct coefficient K of an indoor unit of the air conditioning system, a volume V of the indoor unit, a flow cross-sectional area S of the air supply fan, and a response time of the air valve

Determining said dead time t_deadInvolving the application of formulas

Determining said dead time t_dead。

7. The air mixing control method of air conditioning system according to any of claims 1-4, characterized in that in the current period, if t_p≤T_{CRITICAL_POINT}Shortening the period T, T of the next cycle_{CRITICAL_POINT}Is a preset second safety temperature, t_pIs the collected heat exchanger temperature.

8. The air mix control method of an air conditioning system according to any one of claims 1 to 4, characterized by comprising:

obtaining the temperature t of the heat exchanger_pDetermining t_p≤T_{CRITICAL_POINT}Setting D = 1;

time delay

Then, the temperature t of the heat exchanger is obtained again_pDetermining t_p≤T_{CRITICAL_POINT}Sending a cold protection fault signal, wherein the time delay

For a predetermined time, T_{CRITICAL_POINT}Is a preset second safety temperature, t_pAnd D is the duty ratio of the PWM signal for the acquired temperature of the heat exchanger.

9. A mixed air control apparatus of an air conditioning system, characterized in that the air conditioning system includes: internal loop subsystem and new trend subsystem, mix wind controlling means includes:

the time length determining module is used for determining the time length of a high level signal and the time length of a low level signal of a PWM signal and determining the dead time of the PWM signal;

a timer;

the control module is used for starting a timer and controlling the PWM port to output a high level signal according to the duration of the high level signal; based on the dead time, sending out a mixed wind mode forbidding instruction; after the dead time, issuing a mixed wind mode enabling instruction; starting a timer, and controlling a PWM (pulse width modulation) port to output a low level signal according to the duration of the low level signal; based on the dead time, sending out a mixed wind mode forbidding instruction;

10. An air conditioning system, characterized in that the air conditioning system comprises: an internal circulation subsystem, a fresh air subsystem and a wind mixing control device as claimed in claim 9.

11. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, characterized in that the processor, when executing the program, carries out the steps of the method of controlling the mixing of air of an air-conditioning system according to any one of claims 1 to 8.

12. A non-transitory computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, carries out the steps of the method of controlling the mixing of air of an air-conditioning system according to any one of claims 1 to 8.