JP4336142B2 - Air conditioner communication control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a technique of a bidirectional serial communication control device performed between an indoor unit and an outdoor unit in a separate type air conditioner.
[0002]
[Prior art]
As a general prior art of an air conditioner, in a separate type unit divided into an indoor unit and an outdoor unit, each is equipped with a control circuit controlled by a microcomputer, and the indoor unit is operated by a user using a remote controller, In addition to receiving commands such as a stop request and changing the set temperature, and determining the operating state of the indoor fan, etc., using information from a temperature detection circuit etc. that uses a temperature sensor such as a thermistor that detects the indoor temperature condition Therefore, it is necessary to transfer an operation command such as a rotation speed command of the compressor motor for refrigerant compression and an operation request to the outdoor fan to the outdoor unit.
[0003]
In addition, the outdoor unit needs to transfer the outdoor unit information such as the outdoor temperature information such as the outdoor temperature and the refrigeration cycle, the operation state of the refrigerant compression compressor, and the failure information to the indoor unit. Serial communication between outdoor units is essential.
[0004]
As a conventional technique in serial communication between an indoor unit and an outdoor unit, a communication control device including a rectifier circuit and a photocoupler has been proposed (see, for example, Patent Document 1 and Patent Document 2). According to these patent documents, using a commercial power supply, a half-wave rectifier circuit composed of a diode, a smoothing capacitor, and a resistor is used as a dedicated power supply for serial communication, and a photocoupler that controls the energization timing of a transmission signal A current loop circuit is configured using a photocoupler for reception, a plurality of resistors, and semiconductor elements.
[0005]
[Patent Document 1]
JP2002-213803
[0006]
[Patent Document 2]
Japanese Examined Patent Publication No. 4-303516 [0007]
[Problems to be solved by the invention]
Generally speaking, improvement of comfort and energy saving are major themes in air conditioners. One of the standards of comfort is how quickly the user can adjust to the operating condition that the user wants after operating the air conditioner.To achieve this, the operation command from the indoor unit is quickly sent to the outdoor unit. It is necessary to operate the compressor for compressing the refrigerant and the blower in an appropriate state with respect to the air-conditioning environmental conditions at that time.
[0008]
In addition, for energy saving, it is necessary to control indoor units and outdoor units in a state that is optimal for air conditioning environment conditions such as room temperature and outdoor temperature. Therefore, it is necessary to automatically adjust to the optimum operating state quickly and to suppress the consumption of wasted power. As described above, in the separate type air conditioner, it is required to improve the communication speed between the indoor unit and the outdoor unit in order to improve comfort and save energy.
[0009]
In addition, the increase in additional functions such as home appliance networking in recent years has made control more sophisticated and complicated, the parameters used for control have increased, and the amount of serial communication data between indoor units and outdoor units has also greatly increased. Therefore, it is desired to further increase the indoor / outdoor communication speed.
[0010]
However, in the above-mentioned cited document, since the photocoupler is used for the element for data transmission and reception, speeding up is not suitable. That is, it is known that a photocoupler has a relatively large transmission delay (delay time) among semiconductor elements. In general, a low-priced photocoupler has a transmission delay of several μsec to several tens of μsec. In order to operate stably, it is necessary to secure sufficient on and off times in consideration of this transmission delay. is there. Due to this transmission delay, operation at a relatively low frequency is unavoidable, which limits the communication speed.
[0011]
In addition, although it is possible to improve the communication speed to some extent by making the photocoupler a high-speed type, the cost increases and the communication signal is a current rectangular wave signal containing a lot of harmonics due to the nature of the photocoupler. There is a high possibility that the cable between the indoor and outdoor connecting the photocouplers performs the antenna function and emits radiation noise.
[0012]
In order to drive the photocoupler, it is generally necessary to pass a drive current of about 5 mA to 15 mA to the light emitting side input. In order to obtain this drive current, the commercial power supply is rectified and smoothed by a capacitor, and then a Zener diode And a dedicated power source that makes the voltage constant with a resistor is required, which increases the number of parts and hinders power saving. Furthermore, the photocoupler is a semiconductor element with a relatively low rated current and rated voltage, and a protection circuit against erroneous connection of the connection cable between the indoor unit and the outdoor unit is necessary. Therefore, the circuit is complicated and the number of parts is increased. It becomes the factor of.
[0013]
The objective of this invention is providing the communication apparatus of the air conditioner which aims at speeding up of communication between an indoor unit and an outdoor unit, and suppressing radiation noise by communication.
[0014]
[Means for Solving the Problems]
In order to solve the above problems, the present invention mainly adopts the following configuration.
Indoor unit having AC power terminal, indoor fan, control system means including microcomputer, temperature detection means, AC-DC converter, outdoor fan, refrigerant compressor, control system means including microcomputer, temperature detection means, AC-DC An outdoor unit having a converter, and a separate type air conditioner,
Provided between the indoor unit and the outdoor unit are two connection cables for supplying the AC power and one communication cable for communication,
A high-frequency transformer in which both ends of a primary winding are connected to one of the two connection cables and the communication cable is provided in each of the indoor unit and the outdoor unit,
By connecting a capacitor in parallel with the primary side winding of the high-frequency transformer to form a parallel resonance circuit, the carrier of the communication signal flowing through the communication cable is a sine wave waveform close to a sine wave,
The sinusoidal waveform resulting from the inductance component of the communication cable by connecting a resistor between the primary winding of the high-frequency transformer of either or both of the indoor unit and the outdoor unit and the communication cable The high-frequency ringing generated in the circuit is attenuated .
[0016]
Moreover, in the communication control device of the air conditioner, the secondary winding side of the high-frequency transformer is connected to the control system means,
The signal from the control system means is converted into the sinusoidal waveform by the parallel resonance circuit and transmitted as an operation command from the indoor unit to the outdoor unit through the communication cable,
The outdoor unit transmits outdoor unit information including operation information of the outdoor unit, information from the temperature detection means of the outdoor unit, and failure information of the outdoor unit,
The indoor unit is configured to receive the outdoor unit information from the outdoor unit and determine an operation state using user operation information and information from a temperature detection unit of the indoor unit.
[0017]
By adopting such a configuration, it is possible to increase the communication speed between the indoor unit and the outdoor unit and to suppress radiation noise due to communication.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
An air conditioner communication control apparatus according to an embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a diagram illustrating an overall configuration of a communication control device for an air conditioner according to an embodiment of the present invention.
[0019]
In FIG. 1, 1 is an indoor unit, 6 is an AC-DC converter for generating a voltage required to operate a control system such as a microcomputer of the indoor unit 1 from a commercial power source, 7 is a microcomputer, and 8 is an indoor fan. Power supply and drive circuit for driving, 9 is a demodulating circuit for communication signal from outdoor unit, 10 is a parallel resistor for preventing ringing and adjusting carrier amplitude of communication signal, 11 is a coupling capacitor for receiving , 12 is a driver for modulation, 13 is a resistor for limiting the drive current of the high-frequency transformer, 14 is a high-frequency transformer for transmitting / receiving communication signals, and 15 is a parallel resonance circuit with the inductance of the primary winding of the high-frequency transformer 16 is a misconnection protection capacitor, 17 is a series resistor for preventing ringing, 18 is a temperature detection circuit, and 19 is a mode of an indoor fan. , 20 denotes a varistor for surge absorption, respectively, constituting the indoor unit with these components.
[0020]
Here, the winding side of the high-frequency transformer 14 connected to the commercial power supply side is referred to as a primary side, and the winding side of the high-frequency transformer 14 connected to the control signal side is referred to as a secondary side. The function or action of ringing will be described later with reference to FIG.
[0021]
On the other hand, 2 is an outdoor unit, 21 is a temperature detection circuit for the outdoor unit, 22 is a demodulation circuit for a communication signal from the indoor unit, 23 is a coupling capacitor for reception, 24 is a ringing prevention and communication signal carrier amplitude. A parallel resistor for adjustment, 25 is a high-frequency transformer for transmitting and receiving communication signals, 26 is a resistor for limiting the drive current of the high-frequency transformer, and 27 is a parallel resonance circuit with the inductance of the primary winding of the high-frequency transformer. Capacitor, 28 is a series resistor for preventing ringing, 29 is a capacitor for protecting misconnection, 30 is a driver for modulation, 31 is a microcomputer, and 32 is an AC that generates a voltage for driving a microcomputer and other control circuits of the outdoor unit. DC converter, 33 is a converter and drive circuit for supplying a voltage to the compressor for refrigerant compression, and 34 is a drive circuit for an outdoor fan 35 represents the outdoor blower motor, 36 denotes a motor for a refrigerant compressor for a compressor, 37 is a varistor for surge absorption, respectively, constituting the outdoor unit in these components. Further, 3 and 4 are internal / external connection cables for supplying commercial power to the outdoor unit, and 5 is a serial communication cable.
[0022]
In the indoor unit 1, when a user's operation start operation by a remote controller or the like is received, the indoor temperature information from the temperature detection circuit 18 is extracted from the outdoor unit extracted via the high-frequency transformer 14, the coupling capacitor 11, and the demodulation circuit 9. In consideration of the above information, the microcomputer 7 comprehensively determines the operation mode, sends the transmission signal carried on the high-frequency carrier signal to the secondary side of the high-frequency transformer 14 via the driver 12 and the limiting resistor 13 It is given to the winding and propagated to the primary side through the core.
[0023]
This propagated signal is shaped into a high frequency signal close to a sine wave by a parallel resonance circuit composed of a capacitor 15 connected in parallel with the inductance of the primary winding of the high frequency transformer 14 and superimposed on the serial communication cable. And transferred to the outdoor unit 2.
[0024]
On the other hand, the outdoor unit 2 transmits a serial communication signal transmitted from the indoor unit 1 superimposed on the serial communication cable 5 on the basis of one of the connection cables 3 and 4 of the indoor / outdoor unit as a primary winding of the high-frequency transformer 25. And output to the secondary winding through the core. Next, the signal is input to the demodulation circuit 22 through the coupling capacitor 23, demodulated after removing the high frequency carrier, and input to the microcomputer 31 of the outdoor unit 2. The outdoor unit microcomputer 31 receives a command by a serial communication signal from the indoor unit 1 and determines operating conditions of the refrigerant compression compressor 36 and the outdoor blower 35. Similarly, transmission of information from the outdoor unit 2 is performed to the indoor unit 1 and the transmission of these information is sequentially repeated. The failure information of the outdoor unit 2 is transmitted to the indoor unit 1 in the same manner.
[0025]
Next, modulation and demodulation of the serial communication signal will be described below with reference to FIGS. Transmission of the serial communication signal from the indoor unit 1 to the outdoor unit 2 will be described by taking as an example a case where the user changes the set temperature of the air conditioner. FIG. 2 is a diagram illustrating specific configurations of the modulation circuit and the demodulation circuit of the indoor unit according to the present embodiment, and FIG. 3 is a diagram illustrating waveforms at each point in FIG.
[0026]
In response to an operation of the user's remote controller or the like, the contents are analyzed, rotational speed commands of various outdoor units such as the refrigerant compression compressor 36 and the outdoor blower 35 are calculated, and the changed contents are transmitted to the outdoor unit 2. As shown in the transmission data of FIG. 3, when the transmission data is, for example, 8 bits per frame, the start bit ST is output at the head, the data string D0 to D7 is output, and the stop bit SP is added at the end. Convert to a series of transmission data strings. From the transmission output of the microcomputer 7 shown in FIG. 2, a rectangular signal including a high frequency carrier frequency such as the point A voltage shown in FIG. 3 is output. Since the microcomputer 7 handles binary signals, it becomes a rectangular signal such as the voltage at point A in FIG. Here, a repetitive signal of a rectangular wave at each bit (any bit of D0 to D7) is referred to as a carrier.
[0027]
The modulation driver 12 shown in FIG. 2 is driven by the microcomputer transmission output (point A voltage), and a high frequency current is caused to flow through the secondary winding of the high frequency transformer 14. The high-frequency transformer 14 outputs to the primary winding through the core, but forms a filter that selectively transmits the carrier frequency by a parallel resonance circuit with the capacitor 15 connected in parallel to the inductance of the primary winding. Therefore, it is formed into a smooth AC signal close to a sine wave like the voltage at point C in FIG. 3 and transmitted to the outdoor unit 2 via the serial communication cable 5 shown in FIG.
[0028]
Further, this transmission signal can be prevented from being attenuated because a high-frequency impedance is given by a sufficiently large inductance of the high-frequency transformer 25 mounted in the outdoor unit 2 in the same manner. 2 and 3 are examples in which a data string and a high-frequency transmission carrier are pre-combined and output from the microcomputer transmission port. However, if the above output cannot be obtained due to restrictions on the performance of the microcomputer. The same effect can be obtained by driving the high-frequency transformer 14 after an oscillation circuit is provided outside the microcomputer 7 and the data string and the high-frequency carrier are synthesized by the OR circuit.
[0029]
Next, a method for receiving a serial communication signal from the outdoor unit 2 will be described. A serial communication signal transmitted from the outdoor unit 2 in the same manner as described above is received via the serial communication cable 5 in FIG. 2 in a waveform such as the voltage at point C at the time of reception in FIG. The signal at point C is input to the primary winding of the high-frequency transformer 14 in FIG. 2, is output to the secondary winding through the core of the high-frequency transformer 14, and is transmitted to the secondary winding via the coupling capacitor 11 shown in FIG. Like the D point voltage at the time of reception, the signal is superimposed on a predetermined bias voltage and input to the demodulation circuit 9.
[0030]
The signal of the point D voltage is compared with the comparison voltage equal to the bias voltage in the comparison circuit 9-a using the comparator, and the output is inverted only in the voltage range exceeding the comparison voltage of the point D voltage at the time of reception in FIG. . Since the output signal at this time includes a high-frequency carrier component, it is smoothed by the resistor R and capacitor C provided in the demodulation circuit 9 of FIG. Demodulated as a data string such as the voltage at point E at the time of reception in FIG. The transmission / reception method in the outdoor unit 2 is the same, and transmission / reception is repeated alternately.
[0031]
Next, a mode in which the high-frequency carrier of the serial communication signal is brought close to a sine wave will be described with reference to FIG. As described above, the high frequency rectangular signal output from the microcomputer 7 is selectively transmitted to the carrier frequency by the parallel resonance circuit with the capacitor 15 connected in parallel to the inductance of the primary side winding of the high frequency transformer 14. A filter is formed and smoothed to approximate a sine wave.
[0032]
FIG. 4 shows that the inductance of the primary and secondary windings of the high frequency transformer is 0.5 mH, the capacitance of the misconnection prevention capacitor 16 is 0.01 μF, the ringing prevention resistor 17 is 20Ω, and the parallel resonant capacitor 15 The voltage waveform superimposed on the serial communication cable 5 when only the capacitance is changed is shown. In the case of this configuration example, the carrier frequency is set to 30 kHz, but the resonance capacitor is changed from 0.01 μF (f0 = about 70 kHz) to 0.033 μF (f0 = about 40 kHz) to 0.047 μ (f0 = about 30 kHz). The closer the carrier frequency and the resonant frequency of the parallel resonant circuit are, the smoother the waveform is.
[0033]
Next, the function or operation of the ringing preventing resistors 17 and 28 will be described. When the wiring of the indoor / outdoor unit connection cable 4 and the serial communication cable 5 shown in FIG. 2 is long, ringing may occur due to an inductance component. Therefore, as shown in FIG. 5, it is possible to prevent ringing that may be a noise source by adding series resistors 17 and 28 for preventing ringing. FIG. 5 shows a comparison of communication signal waveforms when there is no ringing prevention resistor and when a resistor for preventing ringing is added. In addition, even if the resistance for preventing ringing is provided on one of the indoor and outdoor units, the function of preventing ringing can be achieved similarly.
[0034]
Further, in the embodiment of the present invention, protection at the time of cable connection is performed by the erroneous connection protection capacitors 16 and 29 of FIG. Capacitors 16 and 29 for preventing improper connection that are solutions when the cable 5 is erroneously connected to the cable 3 need to be able to withstand a commercial power supply at the time of erroneous connection. Then, a withstand voltage of AC250V is required, but these are available as film capacitors at low cost. Furthermore, in this embodiment, a varistor is connected to the circuit positions indicated by reference numerals 20 and 37 in the circuit configuration shown in FIG. 1 to absorb a surge voltage flowing from a commercial power source.
[0035]
In other words, the embodiment of the present invention is characterized by the following configurations, functions, and actions. That is, in the present embodiment, two cables 3 and 4 for supplying commercial power and one serial communication cable 5 are connected to the indoor unit 1 and the outdoor unit 2 to supply commercial power to the outdoor unit. There are provided high frequency transformers 14 and 25 having primary side inductances in which one cable 4 and serial communication cable 5 are connected at both ends. Further, in order to transmit and receive serial communication signals using high frequency signals as carriers, capacitors 15 and 27 are connected in parallel to the primary side inductances of the high frequency transformers 14 and 25, and a filter that selectively transmits the carrier frequency is provided. By forming the communication signal carrier close to a sine wave and smoothing, and by adding series resistors 17 and 28, unnecessary ringing generated due to the influence of the inductance component of the cable is suppressed, thereby radiating noise and the like. Reduce the amount of noise generated.
[0036]
Further, the ratio of the number of turns of the primary winding N1 of the high-frequency transformer to the number of turns N2 of the secondary winding is set to N1 / N2 (N1 <N2), and the carrier amplitude is arbitrarily adjusted to suppress noise such as noise terminal voltage. (This function or action will be described later). In addition, capacitors 16 and 29 that can withstand the voltage of the commercial power supply are connected in series to the primary side of the high-frequency transformer to provide protection against misconnection even with a simple circuit configuration, and voltage surges flowing from the commercial power supply are varistors. Absorb at 20 and 37.
[0037]
By adopting such a configuration, the serial communication means of the indoor / outdoor unit of the separate type air conditioner can superimpose (transmit) the signal on the serial communication cable and extract (receive) the signal from the serial signal cable. In addition, a serial device with one end connected to the control potential on the microcomputer side and the commercial power supply is used without using a semiconductor device such as a photocoupler with a relatively large signal transmission delay and using an insulated high-frequency transformer between the primary and secondary sides. There is no need to add dedicated parts to insulate the potential on the communication cable side, and there is no need to take into account signal transmission delays. An external serial communication device can be realized. Furthermore, by using a high-frequency transformer having high withstand voltage performance between the primary and secondary, the primary side potential connected to the commercial power supply and the secondary side potential of the control circuit which is a low voltage can be insulated.
[0038]
In addition, by connecting a capacitor in parallel with the inductance of the primary winding of the high-frequency transformer connected to the serial communication cable side, a parallel resonant circuit is formed, thereby forming a filter that selectively transmits the carrier frequency. Since harmonic components can be suppressed by smoothing the carrier of the communication signal close to a sine wave, it is possible to suppress the generation of noise such as noise terminal voltage and radiation noise. In addition, with regard to the number of turns N1 of the primary winding and the number of turns N2 of the secondary winding, it is possible to suppress noise such as a noise terminal voltage by arbitrarily adjusting the carrier amplitude in a relationship of (N1 <N2). .
[0039]
Here, a cable to the outdoor unit of the air conditioner, particularly a communication cable that handles high-frequency signals, functions as an antenna and emits radio waves, which can be harmful noise and noise. Such radiated noise from communication cables is regulated to be low because it adversely affects electric and electronic devices used at home. When a rectangular wave signal such as the point B voltage shown in FIG. 3 flows through the communication cable, a certain high-order harmonic component in the rectangular wave signal can be a source of radiation noise. A resonance circuit is configured by connecting a capacitor 15 to form a sinusoidal waveform close to a sine wave as shown by the voltage at point C in FIG. 3 so as to eliminate radiation noise due to higher harmonic components as much as possible. In addition, if the amplitude of the communication signal flowing through the cable 5 is large, the radiation noise can be increased accordingly. Therefore, it is required to make the amplitude of the communication signal as small as possible from the viewpoint of eliminating the radiation noise. From this point of view, the number of windings is N1 <N2.
[0040]
Furthermore, in this embodiment, since there is no power supply dedicated to the communication circuit, it is possible to contribute to the reduction of the number of parts and power saving, and to the serial communication cable of the primary winding of the high-frequency transformer connected to the serial communication cable side. By connecting a capacitor with a withstand voltage capability that can withstand the voltage of the commercial power supply in series with the connected terminal, even with a simple circuit configuration with a very small number of parts, the serial communication cable can be Even when the internal / external connection cable connected to the commercial power supply is mistakenly connected to the serial communication cable during connection work, destruction or failure can be prevented. Further, since the voltage surge flowing from the commercial power source can be absorbed by the varistor, it is possible to prevent the communication circuit from being destroyed and to prevent unnecessary noise from flowing into the serial communication signal.
[0041]
【The invention's effect】
According to the present invention, high-speed communication can be realized with a simple circuit configuration, and since the number of components is small, space saving and cost reduction can be achieved. Furthermore, since the carrier signal can be made into a smooth waveform close to a sine wave by the parallel resonance circuit, a remarkable effect can be obtained for suppressing radiation noise. In addition, it is possible to save power since a signal can be voltageed by a high frequency transformer without requiring an isolated separate power source as in the photocoupler system.
[Brief description of the drawings]
FIG. 1 is a diagram showing an overall configuration of a communication control apparatus for an air conditioner according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating a specific configuration of a modulation circuit and a demodulation circuit of an indoor unit according to the present embodiment.
FIG. 3 is a diagram showing a waveform at each point in FIG. 2;
FIG. 4 is a diagram illustrating a form in which a high-frequency carrier of a serial communication signal used in the present embodiment is brought close to a sine wave.
FIG. 5 is a comparison diagram of communication signal waveforms in the presence or absence of a ringing preventing series resistor used in the present embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Indoor unit 2 Outdoor unit 3 Indoor / outdoor unit connection cable 4 Indoor / outdoor unit connection cable 5 Serial communication cable 6 AC-DC converter 7 Microcomputer 8 Indoor fan drive power supply and drive circuit 9 Demodulation circuit 10 Parallel resistor 11 Cup Ring capacitor 12 Modulation driver 13 Current limiting resistor 14 High frequency transformer 15 Parallel resonant capacitor 16 Misconnection protection capacitor 17 Ringing prevention series resistor 18 Temperature detection circuit 19 Indoor fan motor 20 Varistor 21 Outdoor unit temperature detection circuit 22 Demodulator 23 Coupling Capacitor 24 Parallel Resistor 25 High Frequency Transformer 26 Current Limiting Resistor 27 Parallel Resonant Capacitor 28 Ringing Prevention Series Resistor 29 Misconnection Protection Capacitor 30 Modulation Driver 31 Microcomputer 32 AC-DC Converter 33 Refrigerant Pressure For a use compressor converter and the drive circuit 34 outdoor blower for drive circuit 35 outdoor blower motor 36 refrigerant compressor for the compressor motor 36 varistor 9-a comparator voltage comparator 9-b buffer circuit

Claims (6)

Indoor unit having AC power terminal, indoor fan, control system means including microcomputer, temperature detection means, AC-DC converter, outdoor fan, refrigerant compressor, control system means including microcomputer, temperature detection means, AC-DC An outdoor unit having a converter, and a separate type air conditioner,
Provided between the indoor unit and the outdoor unit are two connection cables for supplying the AC power and one communication cable for communication,
A high-frequency transformer in which both ends of a primary winding are connected to one of the two connection cables and the communication cable is provided in each of the indoor unit and the outdoor unit,
By connecting a capacitor in parallel with the primary side winding of the high-frequency transformer to form a parallel resonance circuit, the carrier of the communication signal flowing through the communication cable is a sine wave waveform close to a sine wave,
The sinusoidal waveform resulting from the inductance component of the communication cable by connecting a resistor between the primary winding of the high-frequency transformer of either or both of the indoor unit and the outdoor unit and the communication cable A communication control device for an air conditioner characterized by attenuating high-frequency ringing generated in the air conditioner. In claim 1,
A communication control apparatus for an air conditioner, wherein a primary side potential connected to the AC power supply side of the high-frequency transformer and a secondary side potential connected to the control system means side are insulated. In claim 1 or 2,
A communication device for an air conditioner, wherein a capacitor that can withstand the voltage of the AC power supply is connected between a primary winding of the high-frequency transformer and the communication cable.
A communication control device for an air conditioner. In claim 1, 2 or 3,
A communication control device for an air conditioner, wherein a varistor is connected between the connection cable and the communication cable.
A communication control device for an air conditioner. In claim 1, 2 or 3,
A communication control device for an air conditioner, wherein the number N1 of primary windings of the high-frequency transformer and the number N2 of secondary windings satisfy a relationship of N1 <N2. In claim 1,
Connecting the secondary winding side of the high-frequency transformer to the control system means;
The signal from the control system means is converted into the sinusoidal waveform by the parallel resonance circuit and transmitted as an operation command from the indoor unit to the outdoor unit through the communication cable,
The outdoor unit transmits outdoor unit information including operation information of the outdoor unit, information from the temperature detection means of the outdoor unit, and failure information of the outdoor unit,
The indoor unit receives the outdoor unit information from the outdoor unit, and determines an operating state using user operation information and information from the temperature detection means of the indoor unit. Communication control device.

Images