JPH04169733A - Controller of air conditioner - Google Patents

Abstract

PURPOSE:To provide an air conditioner capable of minimizing an outdoor unit by miniaturizing a pump to the utmost by providing a control part that changes the frequency of three-phase AC power supplied to a pump three-phase induction motor bad upon a predetermined law. CONSTITUTION:A compressor 3 is connected to an output of a three-phase inverter circuit 65 and is driven by three-phase AC power. The compressor 3 employs a three-phase induction motor as a driving source and hence its capability can be altered by changing the frequency of the supplied AC power. For changing the frequency of the AC power an on/off pattern of six transistors may be varied, and since the on/off pattern is evaluated by a microprocessor 62 on the basis of a PWM theory, the microprocessor 62 can control the frequency of the AC power supplied to the compressor to provide a required capability to the same on the basis of a signal fed from a microprocessor 50. Thus, a smaller rated output pump can be employed for its miniaturization and for miniaturization of an outdoor unit.

Description

Detailed Description of the Invention (a) Industrial Application Field The present invention relates to a refrigeration cycle in which a compressor, a condenser, a pressure reducer, and an evaporator are sequentially connected in a ring through refrigerant piping, and a system in which the amount of hot water circulated can be arbitrarily changed. The outdoor unit has at least a compressor, a condenser in the refrigeration cycle, a pump in the hot water circuit, and a heating device. This invention particularly relates to the control of hot water circulation pumps in air conditioners housed in the same outdoor unit.

2. Description of the Related Art An air conditioner equipped with a refrigeration cycle and a hot water circuit is described in Japanese Patent Application Laid-open No. 117739/1983. In the system described in this publication, the hot water circulation pump is simply controlled in 0N10FF mode in accordance with the heating operation of the conditioned room and the operation/stop of the heating device.

(c) Problems to be solved by the invention In conventional pump control such as this, the operation is simply controlled at 0N10.
FFL was always there. For this reason, it is often not possible to obtain a circulating amount of hot water commensurate with the air conditioning load, and waste may occur due to insufficient or excessive air conditioning capacity. Note that it is possible to change the amount of hot water circulation by pulling out the speed control tap from the motor winding for driving the pump, but in this case, the number of variable steps in the hot water circulation capacity is limited to the number of speed control taps. However, the problem of pump capacity shortages and excess capacity still remained unresolved.

In addition, to protect this pump, a temperature switch is installed on the stator winding of the drive motor that operates above a specified temperature, and when the temperature of the motor exceeds a specified temperature, the power to the motor is stopped. The system was designed to stop pump operation. If the pump is protected by simply using a temperature switch in this way, there is a problem in that the pump stops operating even when the temperature rises due to overload.

In addition, in an air conditioner having such a refrigeration cycle and hot water circuit, the outdoor unit includes a refrigeration cycle compressor,
It houses a condenser, a heating device for the hot water circuit (consisting of a burner and a heat exchanger), and a pump, and the volume of the outdoor unit increases to accommodate the refrigeration cycle and hot water circuit. . That is, since each piece of equipment is relatively large, it has been difficult to downsize the outdoor unit. In this case, it is particularly difficult to miniaturize the heat exchanger when its efficiency is taken into account, and since the burner generates a large amount of heat, there is a limit to its miniaturization due to the effect on surrounding equipment. Therefore, compressors and pumps can be considered as targets for downsizing.

In general, driving by an inverter is known as an effective means for converting a compressor into a /J) type. By using an inverter, it is possible to improve the capacity of the compressor by rotating it at a high speed, and accordingly, the compressor itself can be made into a No. 1 type. On the other hand, a rectifier and smoothing circuit is required to convert alternating current to direct current. When driving a general household compressor, this rectifying and smoothing circuit requires an output of at least about 1.5 kW, which increases the volume.

Next, it is conceivable to similarly increase the rotation speed of the pump and make it smaller. Pumps are generally placed near water, so they have a closed structure to prevent water from entering.

Therefore, when increasing the rotation speed to achieve miniaturization, there is a problem in that sufficient heat dissipation from the motor is not ensured and the temperature protection device is activated frequently, resulting in interruption of operation. Therefore, there is a limit to miniaturization of the pump as well.

In order to solve these problems, the present invention provides an air conditioner that achieves maximum miniaturization of the pump by achieving both high rotation speed and miniaturization of the pump, thereby making it possible to miniaturize the outdoor unit. It is something.

(2) Means for Solving the Problems The present invention provides a compressor, a condenser,
It has a refrigeration cycle in which a pressure reducing device and an evaporator are successively connected in a circular manner through refrigerant piping, and a hot water circuit in which a pump, a heating device, and a radiator are successively connected in a circular manner through hot water piping. The cooling operation of the room to be conditioned is performed by the heat absorption of the evaporator housed in the indoor unit 7 of the room to be conditioned.
In the air conditioner configured to perform heating operation of a room to be conditioned by heat radiation from a radiator housed in a radiator, the pump is a rotary pump driven by a three-phase induction motor,
This air conditioner control device includes a rectifying and smoothing section that converts alternating current supplied from a commercial power source into direct current power, a first wiring circuit that supplies this direct current power to a first inverter section, and a a second inverter section that converts the three-phase AC power into three-phase AC power; a wiring circuit that supplies the three-phase AC power output from the second inverter section to the three-phase induction motor of the pump; and a three-phase induction motor of the pump. and a control unit that changes the frequency of the three-phase AC power supplied to the AC power based on a predetermined law.

The present invention also provides a pump that can arbitrarily change the amount of hot water circulated;
It has a hot water circuit in which a heating device and a radiator are sequentially connected in a ring with hot water piping, and the heating operation of the conditioned room is performed by heat radiation from the radiator housed in the indoor unit of the conditioned room. In the air conditioner, the pump is a rotary pump driven by an electric motor, and the control device of the air conditioner is configured to control the rotation speed of the electric motor of the pump based on a control signal given to it. a temperature sensor that detects the temperature of the pump or the temperature of the windings of the motor; and a temperature sensor that stops the operation of the pump when the temperature detected by the temperature sensor exceeds a first temperature. and a protection unit that corrects the control signal to lower the rotation speed of the pump when the temperature detected by the temperature sensor is lower than the first temperature and higher than the second temperature.

The present invention also provides a pump that can arbitrarily change the amount of hot water circulated;
It has a hot water circuit in which a heating device and a radiator are sequentially connected in a ring with hot water piping, and the heating operation of the conditioned room is performed by heat radiation from the radiator housed in the indoor unit of the conditioned room. In the air conditioner, a rotary pump driven by a three-phase induction motor is used as the pump, and the control device of the air conditioner receives three-phase AC power at a frequency corresponding to a given frequency signal. an inverter unit that supplies the three-phase induction motor; a temperature sensor that detects the temperature of the pump or the temperature of the windings of the motor; and a temperature sensor that detects the temperature of the pump or the winding of the motor; a protection unit that corrects the control signal by stopping the operation of the pump and lowering the frequency of the three-phase AC power applied to the pump when the temperature detected by the temperature sensor is lower than the first temperature and higher than the second temperature; It is equipped with the following.

Further, the temperature sensor detects the temperature of the bomb or the winding of the motor at predetermined intervals.

Also, a third temperature higher than the second temperature and lower than the first temperature.
and the temperature detected by the temperature sensor is the third temperature.
The correction amount for lowering the rotation speed of the pump when the temperature is higher than the third temperature is set to be larger than the correction amount for lowering the rotation speed of the pump when the temperature detected by the temperature sensor is lower than the third temperature.

(1) When using the control device for air conditioners and Japanese appliances configured in this way, when an overload occurs on the pump for hot water circulation and the temperature of the pump rises, the operating capacity of the pump is lowered to control the temperature. This is something that can be avoided.

(to) Examples Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a system diagram showing an embodiment of the present invention. In the figure, 1 is an outdoor unit and 2 is an indoor unit, which are connected by refrigerant piping, hot water piping, and signal lines. 3 is a compressor, 4
is a condenser, 5 is a capillary tube, 6 is an evaporator, 7
8 is a muffler, and 8 is an accumulator, which are connected to each other through refrigerant piping to form a refrigeration cycle. Furthermore, 9
1 is a service valve, and 10 is a nipple, which is a connection port for refrigerant piping between the outdoor unit 1 and the indoor unit 2. Similarly, 11 is a service valve, and 12 is a nipple, which is also a connection port for refrigerant piping.

The compressor 3 is a hermetic compressor having a three-phase induction motor as a driving source, and the operating capacity of the compressor can be changed by changing the rotation speed of this three-phase induction motor. As a means for changing the rotation speed of the compressor, it is generally known to use an inverter device to change the frequency of AC power supplied to the compressor.

13 is an outdoor fan, which blows air to the condenser 4. 1
Reference numeral 4 denotes an indoor fan, which blows air cooled by the evaporator 6 to the conditioned room. That is, cooling operation can be performed.

When a refrigeration cycle having such a configuration is used, cooling operation can be performed by changing the operating capacity of the compressor 3 based on the difference between the temperature of the room to be conditioned and the set temperature.

15 is a burner, 16 is a hot water heat exchanger, 17 is a radiator,
18 is a pressure tank, and 19 is a pump for hot water circulation, which are connected in a ring using hot water piping. Therefore, by driving the pump 19, hot water (antifreeze) heated in the hot water heat exchanger 6 flows through the radiator 17, and by driving the indoor fan to blow air into the radiator 17, Heating operation of the conditioned room can be performed.

20 is a hot water inlet of the outdoor unit 1, and 21 is a hot water outlet of the indoor unit 2, and these inlets and outlets are connected by hot water piping. 22 is the hot water outlet of the outdoor unit;
23 is a hot water inlet of the indoor unit, which is connected to the hot water pipe in the same manner as described above.

The burner 15 can change the combustion amount, and the solenoid valve 24
, 25 can be opened and closed to obtain four levels of combustion (stop, small, medium, large). Note that 26 is a proportional control valve that adjusts the combustion amount of the burner 15 by changing the amount of fuel supplied. Therefore, by combining the electromagnetic valves 24, 25 and the proportional control valve 26, the combustion amount of the burner 15 can be controlled over a wide range. 27 is a solenoid valve for controlling fuel supply, and 28 is a fuel intake port.

The opening degree of the proportional control valve 26 is changed so that the temperature detected by the hot water thermistor 29 reaches the target value (60'C or 80''C).

By controlling in this manner, the temperature of the hot water is always maintained at the target temperature even if the amount of hot water circulated changes.

The radiator 17 is formed integrally with the evaporator 6,
Its shape will be explained using the cross-sectional view of the indoor unit shown in FIG. In FIG. 2, 30 and 31 are refrigerant pipes,
It is not connected to the evaporator.

32 and 33 are hot water pipes, which are connected to the radiator 17. The evaporator 6 and the radiator 17 are integrally constructed as a heat exchanger that shares fins, and the evaporator 6 is located on the windward side of the air path created by the indoor fan 14, and the heat is radiated on the leeward side. The container 17 is positioned. Therefore, when cooling is performed by the evaporator 6 and heating is performed by the radiator 17 at the same time, the air in the conditioned room flows as indicated by the solid line arrow, and a dehumidifying operation is performed. In addition, 34 is an air intake port, 35 is an air filter, 3
6 is a wind direction changing plate, and 37 is an air outlet. 46 is a solenoid valve that adjusts the flow rate of hot water circulating to the indoor unit.

The opening degree (the amount of hot water circulated) of the solenoid valve 46 is set to match the air conditioning load, based on the set temperature of the conditioned room and the room temperature.

Furthermore, in FIG. 1, numeral 38 is a drain tank, in which hot water (antifreeze) overflowing from the pressure tank 18 is collected. Hot water overflowing from this drain tank is discharged from the drain connection port. 40 is a pressurized water injection port;
It is connected to the hot water pipe connecting the pump 19 and the heat exchanger 16 via the check valve 41. This pressurized water injection port 40 is used when injecting antifreeze into the hot water circuit after the hot water piping between the outdoor unit 1 and the indoor unit 2 is connected. Reference numeral 42 denotes a connection port for the hot water mat 43, which is connected to a hot water pipe connecting the outdoor unit 1 and the indoor unit 2 via a thermal valve 44. This thermal valve 44 is opened when the temperature detected by the temperature sensor 45 reaches a set value (60° C.), and hot water supply to the hot water mat 43 is started.

This hot water mat is placed on the floor of the room to be conditioned and can provide a floor heating effect. In addition, warm water mat 43
is the removal part. In addition, the hot water mat 43 is equipped with a radiator 1.
Hot water having a lower temperature than the hot water supplied to 7 is supplied. A bypass pipe 47 is connected between the outlet of the heat exchanger 16 and the inlet of the pressure tank 18 in the hot water circuit. The thickness of this bypass pipe 47 is thinner than that of the hot water circuit piping, and when the solenoid valve 46 of the indoor unit is fully closed and the solenoid valve 44 is opened, the hot water mat 43
It is thick enough to ensure that the temperature of the hot water that circulates throughout the room is 60 degrees or higher. That is, the bypass pipe 47 is thick enough to circulate hot water to the hot water mat 43 and to heat the hot water with the burner.

FIG. 3 is an electrical circuit diagram used to control the system shown in FIG. 1. In this figure, 5o is a microprocessor that controls the operation of the indoor unit, and this microprocessor 5o obtains operating power from a power supply unit 51. The power supply unit 51 has a current fuse 52 and a plug 5.
It obtains power from a commercial AC power source through 3.
After rectifying and smoothing the AC power, it is controlled to a predetermined DC voltage and supplied to the microprocessor 50 and the power transistor module 54. This power transistor module 54 is made up of a plurality of switching elements connected in a three-phase bridge shape, and is a 0N10FF combination of switching elements based on a signal corresponding to the rotation angle of the indoor fan 14 (driven by a DC brushless motor). By changing the energizing pattern to this DC motor,
This is what keeps the motor rotating. Therefore, the rotation of the indoor fan 14 is maintained.

55 is a step motor, the rotation angle of which is determined by the number of pulses from the microprocessor 5o. This step motor 55 is attached to change the angle of the wind direction changing plate 36 of the indoor unit. Therefore, the wind direction can be changed by increasing the rotation angle of the step motor.

A wireless signal receiving section 56 receives a wireless signal from the remote controller 57 and outputs the received signal to the microprocessor 5o. The remote controller 57 transmits the ON10 F F signal of the air conditioner, a signal representing the room temperature setting value, a signal to switch between cooling/heating, a signal to set the air flow rate of the indoor fan, etc. in response to the user's operation. be.

Reference numeral 58 denotes a switch section, which is a switch for switching the air conditioner between a complete stop, a trial run, and a normal operation.

59 and 60 are temperature sensors that detect the temperature of the evaporator 6 of the indoor unit and the temperature of the conditioned room.

The microprocessor 50 compares the temperature of the room to be conditioned detected by the temperature sensor with the set temperature, determines the magnitude of the load on the room to be conditioned, and determines the level of the load on the room to be conditioned so as to obtain an operating capacity commensurate with the load level. Outputs the signal to the outdoor unit. This signal is converted into a serial signal by the serial signal circuit 61 and then transmitted to the outdoor unit. Furthermore, the microprocessor 50 automatically controls the amount of air blown by the indoor fan 14 based on the difference between the room temperature and the set temperature to provide comfortable air conditioning.

Next, in the outdoor unit, 62 is a microprocessor that controls the operation of the outdoor unit, and receives signals from the microprocessor 50 via a serial signal circuit 63.

64 is a power supply unit, and a plug 53 of the indoor unit
In common with the power supply unit 51, it receives T-power from a commercial power supply, and after rectifying and smoothing AC power, controls it to a predetermined DC voltage and outputs it.

65 is a three-phase inverter circuit supplied with a direct current voltage (DC280 [V)) (7), in which six power transistors are connected in a three-phase bridge configuration. These six transistors 0N10FF can be controlled by signals from the microprocessor 62. The compressor 3 is connected to the output of the three-phase inverter circuit 65 and driven by three-phase AC power output from the three-phase inverter circuit 65. compression@
Since a three-phase induction motor is used as the drive source of compressor 3, the capacity of compressor 3 can be changed by changing the frequency of AC power supplied to this three-phase induction motor (compressor). In order to change the frequency of this AC power, it is sufficient to change the ON10FF pattern of the six transistors. This 0N10FF/< turn is microprocessor 6
2 is calculated based on the generally known PWM theory. Therefore, the microprocessor 62 can control the frequency of the AC power supplied to the compressor based on the signal sent from the microprocessor 50 of the indoor unit so as to obtain the necessary capacity.

Reference numeral 66 denotes a switch section for controlling the operation of the motor for driving the outdoor fan 13, and the operation of this switch section is based on a signal from the microprocessor 62.

Since a brushless DC motor is used as the motor for the outdoor fan, the switch unit 66 changes the DC voltage applied to this motor based on the signal from the microprocessor 62 to control the rotational speed of the motor, that is, the amount of air blown by the outdoor fan. It is something to do.

67 is an inverter section for the pump, and the source unit 64
It converts DC power supplied from the AC into AC power at a predetermined frequency. The difference between this inverter section 67 and the three-phase inverter circuit 65 described above is that the inverter section 65 further includes a controller section that creates a 0N10FF signal of a transistor based on PWM theory, and a protection section for the pump 19. The point is that it has a department. Therefore, the inverter section 67 can output three-phase AC power at a desired frequency by simply supplying a desired frequency signal. The pump 19 is a rotary pump having a three-phase induction motor as a driving source, and the hot water circulation capacity of the pump 19 can be changed by changing the rotation speed of this motor (frequency of AC power applied to the IF motor). . Further, the pump 19 has the electric motor and the pump section provided in separate spaces to prevent hot water from entering the electric motor, and the electric motor and the pump section are connected by a permanent magnet.

A temperature sensor 68 detects the temperature of the pump 19, for example, the temperature of a stator winding of a driving motor. The protection section of the inverter section 67 performs a predetermined protection operation when this temperature becomes higher than a set value. Further, this protection section performs a predetermined protection operation when the current flowing through the motor becomes higher than a predetermined value. These protective operations will be described later.

69 is a burner control section, and a microprocessor 62
Depending on the signal from the burner 15, the combustion amount of the burner 15 and the pump 1
The hot water is circulated by controlling the amount of circulation in 9 and the opening/closing and opening degree of each electromagnetic valve.

The burner control unit 69 controls the solenoid valves 24 to 27 so that the set value of the hot water temperature detected by the temperature sensor 29 shown in FIG. The combustion amount of the burner is changed by controlling the opening/closing and opening degree of the burner. ■When the hot water temperature set value is 80 degrees, the frequency of the AC power applied to the pump 19 is set to the first frequency, and when the set value is 60 degrees, the frequency of the AC power applied to the pump 19 is set to the second frequency. (first set frequency). ■When the hot water temperature setting is 80 degrees and there is a signal to use the hot water mat 43, when the water temperature detected by the temperature sensor 45 (the temperature of hot water returned from the indoor unit) reaches 60 degrees or more, When opened, hot water is supplied to the hot water mat 43. - When there is no signal to set the hot water temperature to the set value and there is only a signal to use the hot water meter 43, the combustion amount of the non-heater is controlled so that the hot water temperature detected by the temperature sensor 45 is 60 degrees. In other words, only the hot water mat 45 is being operated. At this time, the solenoid valve 44 is opened, and the solenoid valve 46 provided in the hot water pipe of the indoor unit is fully closed. Note that the AC power applied to the pump 19 is set to the second frequency.

FIG. 4 shows an inverter section 67 that controls the operation of the pump 19.
FIG. In this figure, 80 is a microprocessor, which mainly calculates the pattern of the 0N10FF signal to be supplied to the switching elements based on PWM theory. A voltage level signal of H/L is applied to terminal 1.2. Frequency signals are given to terminals 3 and 4,
Microprocessor 80 via interface 81
A frequency signal is supplied to the 82 is a three-phase inverter circuit, six switching elements constitute a three-phase bridge, and supplies positive-phase AC power to the induction motor of the pump 19. The ON10FF states of the six switching elements are switched by the 0N10FF signal from the microprocessor 80. A buffer circuit 83 amplifies the power of the ON10FF signal from the microprocessor 80 and speeds up the discharge of the accumulated charge in the switching element to improve the followability of the ON10FF switching operation. Reference numeral 84 denotes a shunt resistor, and the value of the direct current flowing through the three-phase inverter circuit 82 is detected by detecting a change in the voltage across this resistor. 85 is an A/P (analog/digital) converter that converts the voltage across the shunt resistor 84 into a digital value and outputs it to the microprocessor 80. The microprocessor 80 calculates the t flow value based on this digital value. Reference numerals 86 and 87 are variable resistors that can be set arbitrarily, and are used to set the actual values of the first frequency and the second frequency. The microprocessor 80 inputs the values of the variable resistors 86 and 87 and sets the corresponding frequency value. Therefore, the first
When a frequency is specified, 0N1 is used so that AC power of the frequency corresponding to the value set by the variable resistor 86 can be obtained.
It outputs an 0FF signal, and when a second frequency is designated, it outputs an 0N10FF signal that allows AC power of a frequency corresponding to the value set by the variable resistor 87 to be obtained. For example, the first frequency is 13 (lHz) and the second frequency is 6
It has been set to 0Hz.

FIG. 5 is a flow chart showing the main operations of microprocessor 80 shown in FIG. In this figure, first, a reset operation and initial setting are performed in step S1. Next, in step S2, a determination is made as to whether the voltage levels of terminals 1 and 2 are H/L, and the process proceeds to any one of steps 83 to S4. In step S3, reception of the signals supplied to the terminals 3 and 4 is permitted, and the signals inputted from the terminals 3 and 4 are set as the frequency signal F. In step S4, a frequency of 130 Hz corresponding to the set value of the variable resistor 86 is set as the frequency signal F. In step S5, the □ frequency of 60 Hz corresponding to the set value of the variable resistor 87 is set as the frequency signal F. In step S6, the frequency 172 of 130 Hz corresponding to the set value of the variable resistor 86 is set as the frequency signal F. Next, in step S7,
Temperature T of pump 19 (temperature of stator winding of induction motor)
Then, the electric current iI flowing into the inverter circuit 82 is input.

In step S8, it is determined whether the temperature T is equal to or higher than a temperature that requires temperature protection control. If temperature protection control is required, the process advances to step S9. In step S9, the value of the correction value α is set depending on which zone of the zones shown in FIG. 6 the temperature T is located. As shown in FIG. 6, this zone is divided into three zones: A zone, B zone, and C zone in Sakai, where the temperature is 94 DEG C., 1104 DEG C., and 124 DEG C. Zone B and C when the temperature rises and when the temperature falls.
The zones have different sizes. Zone A is a zone where the pump is stopped immediately (it restarts after 1 minute), and Zone B is a zone where α is corrected (a zone where the frequency is lowered). -5Hz/
40 seconds, and at other times α=-2Hz/40 seconds. After obtaining the correction value α in this manner, the correction of F=F+α is performed in step SIO.

In step S11, it is determined whether the current I is greater than or equal to a predetermined value. This predetermined value is set based on the width of the output of the pump. When the electric current exceeds the predetermined value, the process advances to step S12 and the operation of the pump is stopped. Next, one minute after the pump is stopped, the pump is restarted in step S13. After performing such a protective operation, step S
14, the frequency F0 of the three-phase AC power currently being output from the inverter circuit 82 is input. Next step S
15. In step S16, the frequency signal F and the current frequency F0 are compared, and steps S17 to S19 are performed.
Proceed to one of the following. In these steps, the next output frequency can be increased or decreased by IHz. When the next output frequency is determined, a 0N10FF signal pattern is output to the inverter circuit 82 in step S20 so that AC power of this frequency can be obtained. Also, step S
In No. 20, this 0N10FF signal is output continuously, so that continuous three-phase AC power can be obtained.

When the air conditioner configured as described above is used, the cooling operation is performed using a refrigeration cycle, and the heating operation is performed by circulating hot water. Further, by performing heating operation while operating the refrigeration cycle, dehumidification operation of the conditioned room can be performed. At this time, the temperature of the hot water circulating in the hot water circuit is set to 60 degrees.

In addition, when the pump is running to circulate hot water during heating operation, if the temperature of the pump, that is, the temperature of the electric motor, becomes high, the rotation speed of the electric motor can be lowered to suppress the temperature rise of the pump. .

Therefore, the pump can be operated continuously without stopping. By correcting the rotation speed of the pump according to the temperature of the pump in this manner, even if the pump is made smaller and has a higher rotation speed, it is possible to suppress the pump temperature from rising and stopping the operation of the pump.

Furthermore, the rectification and smoothing circuit used in the compressor's inverter circuit is shared with the pump inverter circuit, eliminating the increase in volume of the rectification and smoothing circuit that occurs when the pump is driven by an inverter. .

(G) Effects of the Invention As described above, the present invention has a hot water circuit in which a pump, a heating device, and a radiator that can arbitrarily change the amount of hot water circulated are sequentially connected in a ring through hot water piping, and In an air conditioner configured to heat a room to be conditioned by heat radiation from a radiator housed in an indoor unit, the pump is a rotary pump driven by an electric motor. The control device of the machine includes a rotation speed control device that controls the rotation speed of the electric motor of the pump in degrees Celsius based on a control signal given thereto, and a temperature sensor that detects the temperature of the pump or the temperature of the windings of the electric motor. When the temperature detected by this temperature sensor becomes equal to or higher than a first temperature, the operation of the pump is stopped, and when the temperature detected by this temperature sensor is lower than the first temperature and higher than the second temperature, the operation of the pump is stopped. Since the control signal is provided with a protection unit that corrects the control signal to lower the rotational speed of the pump, even if the temperature of the motor windings rises, this temperature will not be the first.
If the temperature is below , the operation of the pump is stopped and the rotational speed of the pump is lowered to prevent the temperature of the motor from rising. That is, it is possible to reduce the rotational speed of the pump so that the temperature of the electric motor does not exceed the second temperature, and to continue operating the pump at high power without stopping the operation of the pump.

By controlling in this manner, the amount of hot water circulated increases when the pump is operated at high rotation speeds, so a pump with a smaller rated output can be used. That is, the pump can be made smaller.

In addition, when the electric motor for driving the pump is driven by an inverter, the DC power supply for the inverter can also be used as the drive power supply for the compressor. This also solves the problem of an increase in the amount of water and contributes to the miniaturization of outdoor units. Therefore, by combining the inverter drive of the compressor and the inverter drive of the pump, the outdoor unit of the air conditioner can be downsized to a practical level.
Installation of the outdoor unit allows for easy construction and transportation.

[Brief explanation of the drawing]

Fig. 1 is a system diagram showing an embodiment of the present invention, Fig. 2 is a sectional view of the indoor unit shown in Fig. 1, Fig. 3 is an electric circuit diagram used to control the system shown in Fig. Figure 4 is an electrical circuit diagram of the inverter section that controls the operation of the pump shown in Figure 1, Figure 5 is a flowchart showing the main operations of the microprocessor shown in Figure 4, and Figure 6 is used for temperature control. It is an explanatory diagram of a zone. 1...Outdoor unit, 2...Indoor unit, 3
...Compressor, 15...Burner, 19...
・Pump, 68...Temperature sensor.

Claims (5)

[Claims] (1) A refrigeration cycle consisting of a compressor, a condenser, a pressure reducing device, and an evaporator, which are driven by three-phase alternating current output from a first inverter section whose frequency can be arbitrarily changed, and are connected in order in a circular manner through refrigerant piping. , a hot water circuit in which a pump, a heating device, and a radiator are successively connected in a circular manner through hot water piping. In the air conditioner configured to heat the conditioned room by heat radiation from a radiator housed in the indoor unit of the conditioned room, the pump includes a rotary type driven by a three-phase induction motor. The control device for this air conditioner uses a pump, and includes a rectifying and smoothing section that converts alternating current supplied from a commercial power source into direct current power, and a first
a first wiring circuit that supplies the inverter section; a second inverter section that converts the DC power to arbitrary three-phase AC power;
A wiring circuit that supplies the three-phase AC power output from the second inverter section to the three-phase induction motor of the pump and a frequency of the three-phase AC power that is supplied to the three-phase induction motor of the pump are set according to a predetermined law. What is claimed is: 1. A control device for an air conditioner, comprising: a control unit that changes the air conditioner based on the control unit. (2) It has a hot water circuit consisting of a pump, a heating device, and a radiator that can change the amount of hot water circulated arbitrarily, connected in a ring with hot water piping, and the hot water circuit is made up of a pump, a heating device, and a radiator that can change the amount of hot water circulated at will. In an air conditioner configured to perform heating operation of a room to be conditioned by heat radiation, the pump is a rotary pump driven by an electric motor, and the control device of this air conditioner includes a control device for the pump. a rotation speed control device that controls the rotation speed of the electric motor based on a given control signal; a temperature sensor that detects the temperature of the pump or the temperature of the windings of the electric motor; When the temperature exceeds the first temperature, the operation of the pump is stopped, and when the temperature detected by the temperature sensor is lower than the first temperature and higher than the second temperature, the control signal is corrected to lower the rotation speed of the pump. 1. A control device for an air conditioner, comprising: a protection section for protecting the air conditioner. (3) It has a hot water circuit consisting of a pump, a heating device, and a radiator that can change the amount of hot water circulated arbitrarily, connected in a ring through hot water piping, and the hot water circuit is made up of a pump, a heating device, and a radiator that can change the amount of hot water circulated. In an air conditioner configured to heat a room to be conditioned by heat radiation, the pump is a rotary pump driven by a three-phase induction motor, and the control device of this air conditioner has a an inverter unit that supplies the three-phase induction motor with three-phase alternating current power having a frequency corresponding to the frequency signal received by the motor; a temperature sensor that detects the temperature of the pump or the temperature of the windings of the motor; and a temperature sensor that detects the temperature of the motor. When the temperature detected by the temperature sensor is lower than the first temperature and higher than the second temperature, the operation of the pump is stopped, and when the temperature detected by the temperature sensor is lower than the first temperature and higher than the second temperature, the three-phase alternating current is applied to the pump. A control device for an air conditioner, comprising: a protection unit that applies correction to the control signal to lower the frequency of electric power. (4) The air conditioner control device according to claim 2, wherein the temperature sensor detects the temperature of the winding of the pump or the motor at predetermined intervals. (5) a third temperature higher than the second temperature and lower than the first temperature;
and the temperature detected by the temperature sensor is the third temperature.
The correction amount for lowering the rotation speed of the pump when the temperature is higher than a third temperature is set to be larger than the correction amount for lowering the rotation speed of the pump when the temperature detected by the temperature sensor is lower than a third temperature. A control device for an air conditioner according to claim 3.