JP6314262B1 - Heat source system control device and control method thereof - Google Patents

Abstract

Provided is a control device that can be easily applied to a conventional heat source system and that is directed to energy saving in a primary facility including a heat source unit of the heat source system. A control apparatus 10 according to the present invention is applied to an air conditioning system 12 (which is a heat source system) and corresponds to an inlet temperature corresponding to a temperature of cold / hot water entering a heat source machine 14 and a temperature of cold / warm water exiting therefrom. And setting a control target temperature for the cold / hot water generated by the heat source unit 14 so that the reference temperature is located between the acquired inlet temperature and the acquired outlet temperature. A control signal is output so as to execute temperature control of the cold / hot water generated by the heat source device based on the target temperature. [Selection] Figure 2

Description

  The present invention relates to a control device for a heat source system configured to circulate and supply a medium such as cold / hot water from a primary side facility including a heat source unit to a secondary side facility including an air conditioner, and a control method thereof.

  Generally, a heat source system has a configuration including a heat source unit and a primary pump that pumps a heat medium generated by the heat source unit. For example, air conditioning in a building such as a building, cooling of a machine in a factory, etc. Applied to heating. As a heat source system for air conditioning, an air conditioning system including a primary side facility including a heat source unit and a primary pump and a secondary side facility including an air conditioner or the like is conventionally known and used. A general air conditioning system is configured to supply air (cold water or hot water) from a heat source device to a plurality of air conditioners provided in parallel by a primary pump to air-condition a plurality of air conditioning areas.

  Many proposals for enhancing the energy saving effect in such an air conditioning system have been made, and an example thereof is disclosed in Patent Document 1. In the air conditioning system of Patent Document 1, a local pump is provided for each of a plurality of air conditioners (which are secondary-side equipment) in place of a general control valve, thereby wasteful consumption due to restriction of the control valves. Try to reduce power. Further, the air conditioning system calculates the power consumption of the entire system including the power consumption of the heat source unit and the pump, and calculates the coefficient of performance (COP) of the system from the amount of secondary side heat consumed by the secondary equipment with respect to the power consumption of the entire system. ; Coefficient of Performance) is obtained, and the set temperature of the heat source machine is controlled so that this coefficient of performance is maximized.

JP 2006-275597 A JP 2006-38379 A

  For example, in order to apply the configuration of the air conditioning system described in Patent Document 1 later to a conventional general air conditioning system, a local pump is provided for each of a plurality of air conditioners provided in parallel. Further, it is necessary to further add a control device to the heat source unit in a different place from those air conditioners. Therefore, a large-scale system modification is required, and a great cost is required for introduction.

  On the other hand, when the air conditioning system is used for cooling, for example, it is known that the higher the set temperature (control target temperature) of the chilled water generated by the heat source device is, the higher the energy saving effect compared to the lower case. (See, for example, Patent Document 2). It is also known that wasteful energy can be saved by supplying water at an optimal discharge flow rate according to load fluctuation (flow fluctuation) (see, for example, Patent Document 2). However, since the conventional air conditioning system generally controls the set temperature of the heat source unit and the discharge flow rate of the primary pump at constant values, there is room for improvement in terms of energy saving.

  Accordingly, an object of the present invention is to provide a control device and a control method that can be easily applied to a conventional heat source system and that are directed to energy saving in a primary-side facility including a heat source device. It is in.

According to one aspect of the invention,
A control device applied to a heat source system configured to circulate and supply a medium from a primary side facility including a heat source unit to a secondary side facility,
An inlet temperature acquisition unit for acquiring an inlet temperature corresponding to the temperature of the medium entering the heat source unit;
An outlet temperature acquisition unit for acquiring an outlet temperature corresponding to the temperature of the medium exiting from the heat source unit;
A target temperature setting unit that sets a control target temperature for the medium generated by the heat source device so that a reference temperature is located between the acquired inlet temperature and the acquired outlet temperature;
An output unit that outputs a control signal so as to execute temperature control of the medium generated by the heat source device based on the set target temperature.
A control device is provided.

  The target temperature setting unit may set the target temperature so that the reference temperature is positioned approximately in the middle between the acquired inlet temperature and the acquired outlet temperature.

  Specifically, the target temperature setting unit has a value equal to a half of a difference between the predetermined temperature difference and the absolute value of the acquired inlet temperature and the acquired outlet temperature difference, and the predetermined temperature difference and the reference temperature. A value obtained by shifting the initial target temperature determined based on the above can be obtained, and the value can be set as the target temperature.

  When the primary pump of the primary side equipment is provided with an inverter for controlling the flow rate, the control device is configured so that the difference between the acquired inlet temperature and the acquired outlet temperature becomes a second predetermined temperature difference. And a second output unit for outputting a control signal based on the set control value to the inverter.

Furthermore, according to another aspect of the invention,
A control method of a heat source system configured to circulate and supply a medium from a primary side equipment including a heat source machine and a primary pump to a secondary side equipment,
Obtaining an inlet temperature corresponding to the temperature of the medium entering the heat source unit and an outlet temperature corresponding to the temperature of the medium exiting the heat source unit, respectively.
Setting a control target temperature for the medium generated by the heat source machine such that a reference temperature is located between the acquired inlet temperature and the acquired outlet temperature;
Performing temperature control of the medium generated by the heat source unit based on the set target temperature,
A method for controlling a heat source system is provided.

  According to the one aspect of the present invention, in the heat source system, it is possible to suitably set the target temperature in the control of the heat source unit simply by obtaining and calculating the temperature of the medium (inlet temperature and outlet temperature). Energy saving can be suitably achieved with the side equipment. The control device of this aspect can be easily applied to a conventional heat source system.

It is a lineblock diagram of the heat source system to which the control device concerning a 1st embodiment of the present invention was applied. It is a block diagram of the control device mounted in the heat source system of FIG. It is a flowchart which shows the flow of control by the control apparatus of FIG. It is a graph for demonstrating the temperature setting in the control apparatus of FIG. It is a figure for demonstrating the idea used as the base of control by the control apparatus of FIG. It is a figure for demonstrating the example of temperature setting control by the control apparatus of FIG. It is a lineblock diagram of the heat source system to which the control device concerning a reference embodiment was applied. It is a block diagram of the control device mounted in the heat source system of FIG. It is a flowchart which shows the flow of control by the control apparatus of FIG. It is a figure for demonstrating the example of inverter control by the control apparatus of FIG. It is a block diagram of the heat-source system to which the control apparatus which concerns on 2nd Embodiment of this invention was applied. It is a block diagram of the control device mounted in the heat source system of FIG. It is a figure for demonstrating the example of control by the control apparatus of FIG. It is a figure for demonstrating another example of control by the control apparatus of FIG.

  Embodiments according to the present invention will be described below with reference to the drawings. First, a first embodiment of the present invention will be described.

  As shown in FIG. 1, the heat source system 12 to which the control device 10 according to the first embodiment of the present invention is applied includes a primary side equipment 12A and a secondary side equipment 12B. Here, the heat source system 12 is configured as a heat source system for air conditioning, and more specifically, is configured as a so-called central air conditioning system. The control device 10 is applied to the primary side equipment 12A of the heat source system 12 in particular. Hereinafter, the heat source system may be simply referred to as an air conditioning system.

  The primary side equipment 12 </ b> A includes a heat source device 14 and a primary pump 16. Here, the medium that is pumped from the heat source unit 14 by the primary pump 16 and circulates in the piping system of the air conditioning system 12, that is, the heat medium is water (cold / warm water), but the present invention is that the medium is other than cold / warm water. Is acceptable. Here, the heat source unit 14 is an absorption chiller / heater that generates cold water and hot water, and a chilled / hot water piping system 12 </ b> S including a primary pump 16 is connected thereto. The heat source device 14 uses gas as fuel, and is configured to be able to control the temperature of cold / hot water by controlling the opening of a fuel control valve (not shown). Specifically, the heat source device control device (not shown) is configured to obtain (detect) the temperature of cold / hot water (specifically, the heat source device) based on the output of a temperature sensor (more specifically, a temperature sensor 42 described later). The outlet temperature of the cold / warm water generated in step 1) is controlled so as to control the opening degree of the fuel control valve so as to control the set target temperature. Note that the heat source unit is not limited to having such a configuration, and other fuels such as heavy oil and light oil may be used as the fuel. For example, a heat pump type heat source unit may be used. Alternatively, the heat source device may be configured to connect a cooling tower provided with a blower fan and a cooling water piping system provided with a cooling water pump, or a refrigerator generating cold water, a boiler generating hot water And may have various configurations.

  In addition to the primary pump 16, the cold / hot water piping system 12S includes a plurality of air conditioners 18 (provided in the secondary side equipment 12B). In FIG. 1, two air conditioners 18 are shown, but the number of air conditioners may be one, but is preferably a plurality, and may be three or more. The plurality of air conditioners 18 are arranged in parallel. Each of the air conditioners 18 is provided with a flow rate adjustment valve 20 composed of a two-way valve for adjusting the flow rate of supplied cold / hot water. Furthermore, a bypass passage 22 that bypasses the air conditioner 18 is provided in the cold / hot water piping system 12S.

  Cold / hot water is generated by the heat source unit 14. The cold / hot water is sent from the heat source device 14 to the primary header 26 by the primary pump 16, and is then supplied from the secondary pump 28 to each air conditioner 18 via the secondary header 30. A return valve 31 for adjusting the flow rate is provided between the secondary forward header 30 and the primary forward header 26. The cold / hot water flowing through the one or more air conditioners 18 is returned to the heat source unit 14 through the secondary return header 32 and the primary return header 34 in this order. The bypass passage 22 is provided so as to connect the primary return header 26 and the primary return header 34, thereby ensuring that a constant flow of cold / hot water flows through the cold / hot water piping system 12S regardless of the air conditioning load. doing.

  The air conditioning system 12 is applied to a building such as a building. Although not shown, in the air conditioning system 12, the heat source device 14 and the primary pump 16 provided in the primary equipment are also installed in the basement of the building together with the primary header 26 and the primary return header 34, and a plurality of air conditioners provided in the secondary equipment The machine 18 is installed for each floor. Although not shown, each air conditioner 18 includes an intake fan and is connected to a system-specific intake duct for each air-conditioning area. However, these do not limit the arrangement and configuration of the heat source device 14, the primary pump 16, and the air conditioner 18, respectively.

  The air conditioning system 12 having the above configuration is provided with a plurality of sensors (detectors). The secondary forward header 30 is provided with a pressure sensor P, and the opening degree of the return valve 31 is controlled according to the output from the pressure sensor P by a control mechanism (not shown). In the air conditioning system 12, a flow rate sensor F is provided between the secondary return header 32 and the primary return header 34, and the operation of the secondary pump 28 is performed by a control mechanism (not shown) according to the output from the flow rate sensor. Be controlled. Each of the secondary pumps 28 may be provided with an inverter, and the number of revolutions of the secondary pump 28 may be controlled by controlling the inverter, thereby controlling the discharge flow rate (water supply amount). The control of the flow rate adjusting valve 20 is executed based on a set air conditioning temperature set by a user input from a control panel for each air conditioning area. In addition, illustration of each control mechanism or control panel of the return valve 31, the secondary pump 28, and the flow rate adjusting valve 20, and detailed description thereof are omitted.

  Now, in order to achieve the energy saving of the air conditioning system 12 easily and cost-effectively, the air conditioning system 12 of the first embodiment includes a control device 10 configured to control the set temperature of the heat source unit 14. It is attached. Here, the control apparatus 10 is installed in the basement of the building similarly to the heat source machine 14 and the primary pump 16.

  In general, when considering heat source equipment, in the case of cold water, the water temperature targeted for control, that is, the higher target temperature is higher in energy efficiency than in the case of lower water temperature. Is good. The higher the efficiency, the lower the energy consumption. Therefore, energy consumption can be reduced by suitably controlling the set value of the temperature (outlet temperature) of the cold / hot water generated by the heat source device. However, conventionally, such control of cold / hot water temperature has been generally performed manually based on the experience of a person in charge of management of the heat source unit or the like. Therefore, for example, there is a limit to increase the energy saving effect by executing temperature control in real time.

  In contrast, the control device 10 can automatically control the temperature of the cold / hot water with a simple configuration. Below, the structure of the control apparatus 10 is demonstrated first.

  The control device 10 includes a calculation unit (processing control unit), a storage unit, an input / output interface, and the like, and has a configuration as a so-called computer. Specifically, according to the program stored in the storage unit, the control device 10 can exhibit the functions of the units (means) of the temperature acquisition unit 50, the target temperature setting unit 52, and the output unit 54 (FIG. 2). The temperature acquisition unit 50 includes an inlet temperature acquisition unit 50a and an outlet temperature acquisition unit 50b. The target temperature setting unit 52 includes a subtraction unit 52a and a temperature calculation unit 52b. The control device 10 can have functional units other than these functional units (means).

  The control device 10 includes a temperature sensor (hereinafter referred to as an inlet temperature sensor) 40 for detecting the temperature (inlet temperature) of cold / warm water entering (returning) the heat source device 14 and the temperature (outlet) of the cold / warm water exiting the heat source device 14. A temperature sensor (hereinafter referred to as an outlet temperature sensor) 42 for detecting the temperature is electrically connected to each other. In the air conditioning system 12, the primary header 26 and the primary return header 34 are installed in the basement of the building together with the heat source device 14 and the like. Among these, the primary return header 34 is provided with an inlet temperature sensor 40, and the primary forward header 26 is provided with an outlet temperature sensor 42. As shown in FIG. 1, the primary pump 16 is disposed upstream of the heat source unit 14 and downstream of the primary return header 34, but the inlet temperature sensor 40 is upstream of the heat source unit 14 and primary return header 34. For example, it can be provided between the primary pump 16 and the heat source device 14, and can be provided between the primary return header 34 and the primary pump 16. it can. Similarly, the outlet temperature sensor 42 may be provided between the heat source device 14 and the primary header 26. Further, both and / or one of the inlet temperature sensor 40 and the outlet temperature sensor 42 may be integrally attached to the heat source device 14 so as to suitably detect the temperature of the target cold / hot water.

  An output (output signal) from the inlet temperature sensor 40 is input to the control device 10. Thereby, the inlet temperature acquisition part 50a of the temperature acquisition part 50 acquires the inlet temperature equivalent to the temperature of the cold / hot water which enters into the heat-source equipment 14. FIG. Further, the output from the outlet temperature sensor 42 is input to the control device 10. Thereby, the outlet temperature acquisition part 50b of the temperature acquisition part 50 acquires the outlet temperature equivalent to the temperature of the cold / hot water which comes out of the heat-source equipment 14. FIG. In addition, although the inlet temperature acquisition part 50a and the outlet temperature acquisition part 50b are united as the temperature acquisition part 50, you may be made separate. That is, the temperature acquisition unit that acquires the inlet temperature and the outlet temperature is configured as one temperature acquisition unit 50, but may be configured as two independent temperature acquisition units.

  The inlet temperature acquired by the inlet temperature acquisition unit 50a and the outlet temperature acquired by the outlet temperature acquisition unit 50b are sent to the target temperature setting unit 52. Then, the target temperature setting unit 52 calculates and sets a target temperature that is a target for the control of the heat source device 14 through the subtraction unit 52a and the temperature calculation unit 52b. Note that the subtraction unit 52a and the temperature calculation unit 52b may be integrated in advance.

  The control device 10 is further electrically connected to the control device 10 so as to execute temperature control of the cold / hot water generated by the heat source device 14 based on the target temperature set by the target temperature setting unit 52. 14 outputs a control signal based on the set target temperature. This output is performed by the output unit 54 of the control device 10. When the control signal from the output unit 54 is input to the heat source device control device (not shown) of the heat source device 14, the heat source device control device can control the temperature of the cold / hot water generated therein to the target temperature. it can.

  Next, calculation and control by the control device 10 will be described based on FIGS. 3 and 4. The control described below of the control device 10 may be executed after the state of the air conditioning system 12 reaches a predetermined state after the start (that is, after the start state has elapsed).

  In step S301 of FIG. 3, as described above, the temperature acquisition unit 50 acquires the inlet temperature and the outlet temperature. Next, in step S303, the target temperature is set. In step S305, a control signal based on the set target temperature is output to the heat source unit 14. Here, the setting of the target temperature in step S303 will be described.

  The air conditioning system 12 is configured such that the temperature difference between the inlet temperature and the outlet temperature is a predetermined temperature difference when the air conditioning load is 100%. Here, the case where the cold / hot water produced | generated with the heat-source equipment 14 is specifically cold water is demonstrated, and the detailed description about the case where it is warm water is abbreviate | omitted.

  When the cold / hot water is cold water, that is, when the air conditioning system is used for cooling, the predetermined temperature difference between the inlet temperature and the outlet temperature when the air conditioning load is 100% is set to 5 ° C. This predetermined temperature difference is not limited to 5 ° C., and may be determined according to the performance of the heat source unit 14 of the air conditioning system 12, the size of the building in which it is installed, the air conditioning space, and the like.

  In the air conditioning system 12, the target temperature of the cold / warm water generated in the heat source unit 14, that is, the target temperature of the outlet temperature, is corrected so as to correct the predetermined temperature difference based on the inlet temperature that changes according to the air conditioning load. Set. At this time, the target temperature is determined such that a reference temperature (which is a predetermined temperature) is located between the acquired inlet temperature and the acquired outlet temperature. Here, since the temperature of the chilled water when it is cooled to the maximum with the heat source device 14 is 7 ° C., the maximum value of the inlet temperature is 12 ° C. according to a predetermined temperature difference of 5 ° C. At this time, the reference temperature is determined to be located between the inlet temperature and the outlet temperature, particularly approximately in the middle (preferably in the middle) thereof, and specifically set to 9.5 ° C. . Here, the reference temperature is set as a constant value. Accordingly, here, cold water is generated by the heat source machine, and the predetermined temperature difference is set to 5 ° C. and the reference temperature is set to 9.5 ° C. Therefore, the outlet temperature determined based on them is determined. The initial target temperature, that is, the initial target temperature is 7 ° C. here.

And the target temperature of outlet temperature is defined based on following Formula (1).
y ₁ = 0.5 (Δtsc−x ₁ ) (1)
However, y ₁ is the predetermined the predetermined temperature difference and the temperature of the initial setting of the outlet temperature determined by the reference temperature deviation amount from the (initial setting target temperature) (offset temperature), x ₁ is (acquired inlet The difference between (temperature (detected value)) and (acquired outlet temperature (detected value)), that is, (inlet temperature-outlet temperature), and Δtsc is a predetermined temperature difference itself, which is 5 ° C. here. The coefficient “0.5” in Equation (1) is determined so that the reference temperature is a constant value.

For example, when the air conditioning load is 100%, the inlet temperature is 12 ° C., and the outlet temperature is 7 ° C., y ₁ becomes 0 (° C.). Therefore, in this case, the target temperature of the outlet temperature is set to the initial target temperature itself determined based on the reference temperature and the predetermined temperature difference, and is 7 ° C.

For example, when the air conditioning load is not 100%, the inlet temperature is 10 ° C., and the outlet temperature is 7 ° C., y ₁ becomes 1 (° C.). Accordingly, the target temperature of the outlet temperature is shifted by 1 ° C. from the initial set target temperature. The initial set target temperature is determined according to the performance of the heat source unit 14 and the like. Here, since the air conditioning system is for cooling, the direction in which the target temperature is shifted from the initial set target temperature is the addition side, The target temperature T _T of the outlet temperature is 8 ° C. according to the calculation formula (T _T = “initial setting target temperature” + y ₁ ).

This relationship is shown in the graph of FIG. In the graph of FIG. 4A, the measured temperature difference x ₁ (inlet temperature-outlet temperature) is taken on the horizontal axis, and the deviation amount y ₁ that is the offset temperature is taken on the vertical axis. It is shown. Thus, here, the amount of deviation of the target temperature of the outlet temperature is set by a linear function.

  On the other hand, the case where the cold / hot water produced | generated with the heat-source equipment 14 is warm water, ie, the case where the air conditioning system 12 is used for heating is demonstrated easily. Here, as in the case of cold water, the predetermined temperature difference is 5 ° C., but the reference temperature is 52.5 ° C. The predetermined temperature difference and the reference temperature are merely examples, as in the case of cold water. For example, the predetermined temperature difference may be different between cold water and hot water.

In this case, when the air conditioning load is 100%, the target temperature of the outlet temperature is set to 55 ° C., which is the initial target temperature, and the inlet temperature is 50 ° C. On the other hand, for example, when the air conditioning load is not 100% and the inlet temperature reaches 52 ° C., the outlet temperature target temperature T _T (T _T = “initial setting target temperature” + y ₂ ) is set to 54 ° C. At this time, the deviation amount y ₂ of −1 ° C. is determined based on the following equation (2).
y ₂ = −0.5 (Δtsh−x ₂ ) (2)
However, y ₂ is the amount of deviation (offset temperature) as in y ₁ of equation (1), and x ₂ is the absolute value of the difference between the acquired inlet temperature and the acquired outlet temperature (in other words, outlet temperature−inlet temperature). ) And Δtsh is the predetermined temperature difference itself, which is 5 ° C. here. Note that the coefficient “0.5” in the equation (2) is also set to have a constant reference temperature, like the coefficient “0.5” in the equation (1).

This relationship is shown in the graph of FIG. Graph of FIG. 4 (b), the horizontal axis represents the temperature difference x ₂ actually measured, taking the shift amount y ₂ on the vertical axis, the relationship of the above formula (2) is shown. Thus, here, the amount of deviation of the target temperature of the outlet temperature is set by a linear function.

  Thus, the control device 10 sets the target temperature of the outlet temperature to a half of the difference between the predetermined temperature difference and the absolute value of the difference between the acquired inlet temperature and the acquired outlet temperature (| inlet temperature−outlet temperature |). The initial target temperature that is determined based on the predetermined temperature difference and the reference temperature is set to a value that is shifted.

Here, the effect of the above control will be described with reference to FIGS. FIG. 5 is a diagram for explaining the idea that is the basis of the control, and FIG. 6 is a diagram for explaining the control in the first embodiment. 5 and 6, the horizontal axis represents the discharge flow rate of the primary pump 16, the vertical axis represents the hot and cold water temperature (specifically outlet temperature T _o, the inlet temperature T _i), hatched heat of hot and cold water It is represented by The same applies to FIGS. 10, 13, and 14 described later. Here, the amount of heat of the cold / hot water is, for example, by circulating through the cold / hot water piping system 12S including the amount of heat transferred to (or from) the cold / hot water in the heat source device and the secondary equipment. It means the amount of heat transferred to or from cold / hot water.

First, it demonstrates based on FIG. Figure 5 shows at the time of cold water, when the constant discharge flow rate of the primary pump 16 (5,000L / h), the relationship between the outlet temperature _{T o} and the inlet temperature _{T i.} 5 (a) is, when the air conditioning load is 100%, a 7 ° C. outlet temperature T _o is the maximum cooling temperature, the inlet temperature T _i is the 12 ° C., the temperature difference between them 5 ° C. The case is shown. The heat quantity of the cold / hot water at this time is 25,000 kcal / h because the specific heat of water is 1 (kcal / (L × ° C.)). FIG. 5B shows a case where the target temperature of the outlet temperature is constant in this state, and the inlet temperature _Ti is lowered to 8 ° C. due to a decrease in the air conditioning load. In this way, leaving the target temperature of the outlet temperature as it is even if it becomes a partial load means that the cooling performance of the heat source machine is maintained at the maximum, and those skilled in the art waste energy. You will understand that. Therefore, when the difference between the inlet temperature and the outlet temperature is small, the cooling performance of the air conditioner 18 can be lowered, and therefore it is preferable to increase the target temperature of the outlet temperature from the maximum level equivalent value. This case is shown in FIG. In FIG.5 (c), the place which raised the target temperature of outlet temperature from 7 degreeC to 9 degreeC is shown notionally. In this case, if the air conditioning load is the same as in the case of FIG. 5B, there is a possibility of slight deviation between the case where the outlet temperature is 7 ° C. and the case where the outlet temperature is 9 ° C. The temperature is 1 ° C. higher than the outlet temperature, ie about 10 ° C. Thus, energy saving can be aimed at by raising target temperature. Note that the air conditioning performance (here, the cooling performance) can be substantially the same in the case of FIG. 5B and FIG. 5C because the heat quantity of the cold / hot water is the temperature difference (inlet temperature) of the cold / hot water. (Refer to: “Cold / Hot Water Calorie (kcal / h) = Cold / Hot Water Temperature Difference (° C.) × Cold / Hot Water Flow Rate (L / h) × Specific Heat (kcal)”) / (L × ° C.)) ”).

  However, if the target temperature is increased to, for example, 11 ° C., the cooling performance in the air conditioner 18 may change significantly, and the environment of the air-conditioning area may change greatly due to the control of the target temperature. There is.

Therefore, in the control device 10 according to the first embodiment of the present invention, the heat source machine 14 (of the primary side equipment 12A of the air conditioning system 12) so as to keep the indoor environment (the environment of the air conditioning area) favorable while saving energy. The control is executed. As described above, here, the cold temperature generated by the heat source device is set such that the reference temperature _Tr, which is a reference value for temperature control, is located between the actually measured inlet temperature and outlet temperature. A control target temperature for water is set. More specifically, here, as shown in FIG. 6, so that the reference temperature T inlet temperature _r around the top and bottom of the reference temperature T _r T _i and the outlet temperature T _o is located (i.e., the inlet as intermediate in the reference temperature T _r of the temperature T _i and the outlet temperature T _o is located), the target temperature of the outlet temperature of the heat source machine is set.

  Furthermore, it demonstrates based on FIG. FIG. 6A shows the same state as in FIG. Consider the case where the air conditioning load in that state is 100% and the air conditioning load is 60%. This case is shown in FIG. In this case, if the outlet temperature remains at 7 ° C due to a decrease in air conditioning load, the inlet temperature will be about 10 ° C. However, even if it calculates based on said Formula (1) and sets exit temperature to 8 degreeC, entrance temperature will only become about 11 degreeC and sufficient cooling performance can be ensured. Furthermore, FIG. 6C shows the case where the air conditioning load is 20%. In this case, even if it is calculated based on the above formula (1) and the outlet temperature is set to 9 ° C., the inlet temperature is only about 10 ° C., and sufficient cooling performance suitable for the air conditioning load can be obtained. Energy saving can be achieved by raising the target temperature.

  Thus, energy saving can be effectively achieved only by providing the control device 10 of the first embodiment for controlling the heat source unit 14. And since the control apparatus 10 is applied only with respect to control of the heat source machine 14 only by using the output of the existing or newly provided temperature sensors 40 and 42, the secondary side equipment 12B of the air conditioning system 12 is applied. No equipment change is required. Therefore, the application of the control device 10 to the primary side equipment of the air conditioning system 12 is easy and cost-effective. The application includes a case where the control device 10 is applied later to the primary equipment of the air conditioning system already installed in a building such as a building.

  Next, a second embodiment according to the present invention will be described. Although the control apparatus 10 of the said 1st Embodiment was provided for control of the heat source machine 14, and was comprised as a control apparatus of a heat source machine, the control apparatus which concerns on this 2nd Embodiment controls the heat source machine 14. In addition to this, the control device also controls the primary pump 16. In order to facilitate understanding, before describing the control device 210 according to the second embodiment, first, the control device 110 that controls only the primary pump 16 without controlling the heat source device 14 will be described. The control device 110 is applied to the primary side equipment 12A of the air conditioning system 112 (which is a heat source system). In the following, the constituent elements corresponding to the constituent elements that have already been described are denoted by the same reference numerals, and redundant description is omitted or simplified.

  The primary pump 16 is provided with an inverter 16a. By controlling the inverter 16a, the discharge flow rate (water supply amount) of the primary pump 16 can be changed. That is, the flow rate of the cold / hot water supplied from the heat source unit 14 to the cold / hot water piping system 12S can be changed by controlling the inverter 16a.

  In order to control the inverter 16a, the control device 110 is electrically connected to the inverter 16a. Furthermore, an inlet temperature sensor 40 and an outlet temperature sensor 42 are electrically connected to the control device 110.

  The control device 110 includes a calculation unit (processing control unit), a storage unit, an input / output interface, and the like. Specifically, as shown in FIG. 8, according to the program stored in the storage unit, the control device 110 includes the temperature acquisition unit 50, the control value setting unit 112, and the second output unit 114. Function can be demonstrated. The control value setting unit 112 includes the subtraction unit 52a and the control value calculation unit 112a. The second output unit 114 of the control device 110 outputs a control signal based on the control value (corresponding to the target flow rate) set by the control value setting unit 112 to the control device (not shown) of the inverter 16a.

  Next, calculation and control by the control device 110 will be described with reference to FIG. In step S901, the inlet temperature and outlet temperature are acquired by the temperature acquisition unit 50 as in step S301 described above. Next, in step S903, the control value for the inverter 16a is set. In step S905, a control signal based on the set control value is output to the inverter 16a.

  The control value is calculated and set from a transfer function in feedback control so as to change the discharge flow rate of the primary pump so that the difference between the inlet temperature and the outlet temperature becomes a predetermined temperature difference. Specifically, the control value is calculated and set by a transfer function of PID control. And the control signal based on the set control value is output with respect to the inverter 16a of the primary pump 16, and inverter control is performed.

  The effect by the said control in the control apparatus 110 of reference embodiment is demonstrated based on FIG. FIG. 10 relates to the case where the cold / hot water is cold water.

  FIG. 10 (a) shows the same state as in FIG. 5 (a). Consider the case where the air conditioning load in that state is 100% and the air conditioning load is 80%. This case is shown in FIG. In this case, it is necessary to reduce the flow rate, that is, the discharge flow rate of the primary pump 16 in order to keep the outlet temperature at 7 ° C. and the inlet temperature at 12 ° C. even when the air conditioning load is reduced. Become. The control value corresponding to the target flow rate Fr at this time is set by calculating by substituting the difference between the inlet temperature and the outlet temperature into the predetermined arithmetic expression determined as described above. Since the maximum discharge flow rate of the primary pump 16 is 5000 L / h (see FIG. 10A), in the case of FIG. 10B, the target flow rate is 4000 L / h (= 5000 L / h × 0.80) as a result. A control value corresponding to Fr is set. And the inverter 16a is controlled based on the control value so that it may become this target flow volume. FIG. 10C shows the case where the air conditioning load is 60%. In this case, as a result, a control value corresponding to the target flow rate Fr of 3000 L / h is set. Thus, by controlling the inverter 16a based only on the inlet temperature and the outlet temperature, the air conditioning system 112 can obtain a sufficient cooling performance suitable for the air conditioning load, and the power consumption in the primary pump 16 can be obtained. Energy savings can be achieved by suppressing In addition, it is based on the fact that the amount of heat of cold / warm water is proportional to the flow rate of cold / warm water that sufficient cooling performance suitable for the air conditioning load can be obtained simply by controlling the inverter of the primary pump. (Reference: “Heat amount of cold / hot water (kcal / h) = temperature difference of cold / warm water (° C.) × flow rate of cold / hot water (L / h) × specific heat (kcal / (L × ° C.))”).

  Now, it returns to description of 2nd Embodiment which concerns on this invention. As shown in FIG. 11, the control device 210 according to the second embodiment is a control device 210 that controls both the heat source device 14 and the primary pump 16, and is the primary side of the air conditioning system 212 (which is a heat source system). This is applied to the facility 12A. That is, the control of the control device 210 according to the second embodiment is a combination of the control to the primary equipment in the control device 10 of the first embodiment and the control to the primary equipment in the control device 110 of the reference embodiment. It corresponds to. Therefore, detailed description of these controls will be omitted, and in the following, constituent elements corresponding to those already described will be given the same reference numerals as above, and redundant description will be omitted or simplified.

  The control device 210 is electrically connected to the heat source device 14 and the inverter 16 a of the primary pump 16. In addition, an inlet temperature sensor 40 and an outlet temperature sensor 42 are electrically connected to the control device 210.

  The control device 210 has a configuration as a so-called computer, similar to the control devices 10 and 110. Specifically, as shown in FIG. 12, according to the program stored in the storage unit, the control device 210 includes a temperature acquisition unit 50, a target temperature setting unit 52, an output unit 54, a control value setting unit 112, The function of each part (means) with the second output part 114 can be exhibited. Here, the control value setting unit 112 includes only the control value calculation unit 112a described above without including the subtraction unit 52a. However, the control value setting unit 112 may include a subtraction unit 52a and a control value calculation unit 112a. In this case, the target temperature setting unit 52 does not include the subtraction unit 52a and the subtraction unit of the control value setting unit 112. It may be connected to 52a. Further, the output unit 54 and the second output unit 114 may be integrated.

  The control device 210 is configured to perform both the control of the heat source unit 14 in the first embodiment and the control of the primary pump 16 in the reference embodiment, that is, the control of the inverter 16a. However, here, the control device 210 controls only one of the heat source unit 14 and the inverter 16a to adjust the air conditioning performance in accordance with the air conditioning load (for example, inlet temperature) at that time. Below, control of the heat-source equipment 14 according to an air-conditioning load and control of the inverter 16a are demonstrated based on FIG. Note that FIG. 13 relates to the case where the cold / hot water is cold water, and a description of the case of the hot water is omitted.

FIG. 13A shows the same state as in FIG. 100% air conditioning load in that state, and the temperature difference is the difference between the inlet temperature T _i and the outlet temperature T _o as 5 ° C. (predetermined temperature difference), consider a case where the air conditioning load is changed to 80%. This case is shown in FIG. In this case, similarly to the case of FIG. 6B, the flow rate of the primary pump 16 is constant at the maximum value, and the setting of the outlet temperature of the heat source unit 14 is changed. Specifically, the target temperature of the outlet temperature is changed from 7 ° C. to 7.5 ° C. When the air conditioning load is further reduced, first, the inverter 16a is controlled by fixing the predetermined temperature difference (second predetermined temperature difference), which is the difference between the inlet temperature and the outlet temperature, to a constant value, here 4 ° C. . Specifically, when the air conditioning load changes to 64%, which is lower than 80%, as shown in FIG. 13C, the target temperature of the outlet temperature is the same as that set in the case of FIG. 13B. Remains at the setting of 7.5 ° C., and the inverter control is performed so that the target flow rate Fr is reduced as described in the control in the control device 110 of the reference embodiment. This is continued until the air conditioning load in FIG. 13D is 48%. In the case where the air conditioning load in FIG. 13D is 48%, the control value of the inverter control corresponds to the flow rate of the primary pump 16 of 60%. When the air conditioning load is lower than 48% (for example, when the air conditioning load is reduced to the loads shown in FIGS. 13 (e) and (f)), the target flow rate Fr of the primary pump 16 is maintained at 60%. As described in the first embodiment, the target temperature of the outlet temperature of the heat source unit 14 (that is, the target temperature difference) is varied. When the air conditioning load increases, control opposite to that in the case of FIG. 13 (see the arrow in FIG. 13) is executed. In the case of FIG. 13 as well, the reference temperature _Tr is constant at 9.5 ° C. as in the case of FIG.

  As described above, in the second embodiment, when the air conditioning load is 100% or less and 80% or more (high load region), the air conditioning performance is variable by the control on the heat source unit, and the air conditioning load is less than 80% and 48% or more (medium load region). ), The air conditioning performance is made variable by the control for the inverter, and the air conditioning performance is made variable by the control for the heat source unit when the air conditioning load is less than 48 and 0% or more (low load range). As can be understood from FIGS. 13 (b) to 13 (d), the minimum flow rate of the primary pump is 60% of the maximum flow rate, and the air conditioning load is within the flow rate range in which the primary pump 16 can be used. This is for the purpose of effectively reducing the power consumption in the middle load range.

  As described above, energy saving can be effectively achieved only by providing the control device 210 of the second embodiment for controlling the heat source unit 14 and for controlling the primary pump 16. The control device 210 is applied only to the control of the heat source unit 14 and the primary pump 16 of the primary side equipment 12A only by using the output of the existing or newly provided temperature sensors 40, 42. The equipment change with respect to the secondary side equipment 12B of the system 12 is not required. Therefore, the application of the control device 210 to the primary equipment of the air conditioning system 212 is easy and cost-effective.

  Note that switching between inverter control of the primary pump 16 and control for changing the set temperature of the heat source device 14 is not limited to the example of FIG. 13. The variable flow control of the primary pump 16, that is, the inverter control, is not limited to being executed when the air conditioning load is in the middle load region, and may be performed when the air conditioning load is in the high load region or the low load region. Since the primary pump has a lower limit of the minimum flow rate, the adjustment on the low load side may be performed by control for changing the set temperature of the heat source unit 14. A specific example will be described with reference to FIG. FIG. 14 also relates to the case where the cold / hot water is cold water.

FIG. 14 (a) shows the same state as in FIGS. 5 (a) and 13 (a). Consider a case where the air conditioning load in that state is 100%, the temperature difference that is the difference between the inlet temperature _Ti and the outlet temperature To is 5 ° C., and the air conditioning load changes to 60%. This case is shown in FIG. In this case, the inverter control is executed while the predetermined temperature difference (second predetermined temperature difference), which is the difference between the inlet temperature and the outlet temperature, is fixed to a constant value, here 5 ° C. Specifically, as shown in FIG. 14B, the target temperature of the outlet temperature To remains set at 7.0 ° C., and inverter control is performed as described above. Here, this inverter control is performed when the air conditioning load is 100% or less and 60% or more. This is because the minimum flow rate of the primary pump is 60% of the maximum flow rate. That is, the lower limit of the inverter control is associated with the minimum flow rate of the primary pump. When the air conditioning load is lower than 60%, the flow rate Fr (frequency of the inverter 16a) of the primary pump 16 is maintained at the minimum flow rate (or its equivalent value), as described in the first embodiment (predetermined) The target temperature of the outlet temperature To of the heat source unit 14 (that is, the target temperature difference) is varied while keeping the temperature difference at 5 ° C. as with the second predetermined temperature difference. In the case of FIG. 14 as well, the reference temperature _Tr is constant at 9.5 ° C.

  The predetermined temperature difference in the control of the heat source unit 14 and the second predetermined temperature difference in the inverter control of the primary pump 16 may be different as in the case of FIG. 13, but as in the example of FIG. May be the same. This can be determined according to the setting of switching between inverter control of the primary pump 16 and control for changing the set temperature of the heat source unit 14.

  The first and second embodiments and the modifications thereof according to the present invention have been described above, but the present invention is not limited to them. The present invention can be variously modified within the scope of the idea defined in the claims.

  In each of the first and second embodiments, the control device according to the embodiment of the present invention is applied to the primary equipment of the air conditioning system. However, the present invention is not limited to application to an air conditioning system, and can be applied to a heat source system for other uses other than air conditioning. For example, in a heat source system provided for cooling or heating in a factory or the like, more specifically for cooling or heating in a manufacturing process of a product, or a heat source system configured for cooling or heating machines or chemicals In particular, the present invention is applicable to the primary side equipment. As described above, the present invention is applicable to various heat source systems. This is simply by obtaining (detecting) and calculating the inlet temperature corresponding to the temperature of the medium entering the heat source apparatus and the outlet temperature corresponding to the temperature of the medium exiting the heat source apparatus. This is because the present invention makes it possible to suitably perform control. The primary side equipment may be configured to include a heat source device and a pump for supplying a medium (for example, cold / hot water) generated there as described above, and the secondary side equipment is cooled by the heat of the medium. It is preferable to have a configuration (or mechanism) that provides a heating action.

  For example, in each air conditioning system of the above-described embodiment, the number of heat source units and primary pumps is one, but a plurality may be used. In the first and second embodiments, the reference temperature is located between the acquired inlet temperature and outlet temperature. However, the reference temperature may be biased to the inlet temperature side or the outlet temperature side between them.

10, 110, 210 Controller 12, 112, 212 Air conditioning system (heat source system)
12A Primary side equipment 12B Secondary side equipment 14 Heat source machine 16 Primary pump 18 Air conditioner

Claims (4)

A control device applied to a heat source system configured to circulate and supply a medium from a primary side facility including a heat source unit to a secondary side facility,
An inlet temperature acquisition unit for acquiring an inlet temperature corresponding to the temperature of the medium entering the heat source unit;
An outlet temperature acquisition unit for acquiring an outlet temperature corresponding to the temperature of the medium exiting from the heat source unit;
A target temperature setting unit that sets a target temperature so that a reference temperature that is a predetermined temperature and a constant value is positioned approximately in the middle of the acquired inlet temperature and the acquired outlet temperature;
The predetermined difference between the predetermined temperature difference between the inlet temperature and the outlet temperature when the air conditioning load is 100% and the absolute value of the difference between the acquired inlet temperature and the acquired outlet temperature, the predetermined value and the target temperature setting unit obtains a value obtained by Shifts the initial set target temperature determined based on the temperature difference and said reference temperature, sets the value as the target temperature,
Based on the set the target temperature and an output unit for outputting a control signal to perform temperature control of the medium generated by the heat source equipment, the control device. The primary pump of the primary side equipment is provided with an inverter for flow control,
The controller is
A control value setting unit that sets a control value for the inverter so that a difference between the acquired inlet temperature and the acquired outlet temperature becomes a second predetermined temperature difference;
The control device according to claim 1, further comprising: a second output unit that outputs a control signal based on a set control value to the inverter. A control method of a heat source system configured to circulate and supply a medium from a primary side equipment including a heat source machine and a primary pump to a secondary side equipment,
A step of respectively acquiring an outlet temperature corresponding to the temperature of the medium leaving the inlet temperature and the heat source unit corresponding to the temperature of the medium entering the heat source unit,
A step of setting a target temperature so that a reference temperature that is a predetermined temperature and a constant value is positioned approximately in the middle between the acquired inlet temperature and the acquired outlet temperature,
The predetermined difference between the predetermined temperature difference between the inlet temperature and the outlet temperature when the air conditioning load is 100% and the absolute value of the difference between the acquired inlet temperature and the acquired outlet temperature, the predetermined value a step of seeking the initial set target temperature value Shifts the determined based on the temperature difference and said reference temperature, sets the value as the target temperature,
Based on the set the target temperature and performing a temperature control of the medium generated by the heat source unit, the control method of the heat source system. The primary pump of the primary side equipment is provided with an inverter for flow control,
The control method is:
Setting a control value for the inverter such that a difference between the acquired inlet temperature and the acquired outlet temperature is a second predetermined temperature difference;
The control method according to claim 3, further comprising a second output step of outputting a control signal based on a set control value to the inverter.

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