JPH11218346A - Control device of air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stop supply of power to a compressor motor on the occasion when a supply voltage is off a normal range and fluctuates over to a protective operation range. SOLUTION: AC power is rectified by a rectifier circuit 8 and supplied to a compressor motor through an inverter 9. It is inputted as a reference voltage to one input of each of comparators IC1 and IC2 of a comparator circuit 10. Besides, a supply voltage divided by R1 and R2 is inputted directly to the other input of each of the comparators IC1 and IC2. Outputs of the comparators IC1 and IC2 are connected to a photocoupler 11 composed of PC1 and PC2 and an output VOUT of a junction midpoint thereof is supplied to a microcomputer. Zone determination is conducted according to criteria of determination by the comparators IC1 and IC2, and the output VOUT is VH when VAC > reference voltage + a%. The output VOUT is VM when reference voltage + a% >= VAC >= reference voltage - b%, and VOUT is VL when reference voltage -b% > VAC. When the voltage is outside the range, the microcomputer gives an instruction to stop output of the inverter, or a manual stop is conducted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an air conditioner which performs a protection operation when a power supply voltage of the air conditioner fluctuates.

[0002]

2. Description of the Related Art A separate type air conditioner is composed of an outdoor unit installed outdoors and an indoor unit installed indoors. A refrigerant pipe and a command signal line from each indoor unit are provided between these two units. It is connected.

The indoor unit 2 includes an indoor heat exchanger, a fan motor, an indoor fan including a cross-flow fan driven by the motor and returning the air heated / cooled by the indoor heat exchanger to the room, a refrigerant. A port for piping connection and an indoor control unit are mounted.

The outdoor unit includes an outdoor heat exchanger, an outdoor fan comprising a motor and a propeller fan for promoting heat exchange between the outside air and the outdoor heat exchanger, a compressor and a compressor motor for driving the compressor, and circulation of the refrigerant. A four-way valve for switching the direction, a check valve for regulating the circulation direction of the refrigerant, a solenoid valve 4 for controlling the flow rate of the refrigerant supplied to the indoor unit, a capillary tube (decompression device), a strainer, and a port for connecting refrigerant piping. , An accumulator, a muffler, and an outdoor controller (outdoor unit control board).

[0005] An outdoor unit installed outdoors and an indoor unit installed indoors, each equipped with such a device, have a refrigerant pipe and a terminal plate (terminal).
A refrigeration cycle is configured by connecting with a signal line via the.

With this configuration, during the cooling operation, the refrigerant discharged from the compressor condenses in the outdoor heat exchanger and evaporates in the indoor heat exchanger, thereby discharging the heat in the conditioned room to the outside. Thus, the cooling operation of the conditioned room becomes possible.

During the heating operation, the refrigerant discharged from the compressor condenses in the indoor heat exchanger and evaporates in the outdoor heat exchanger, thereby releasing outdoor heat into the conditioned room. This enables the heating operation.

In performing a cooling, heating or dry operation, a separate type air conditioner transmits a desired operation command signal to an outdoor unit via a communication line. Hereinafter, an outline of an electric circuit configuration of a separate air conditioner according to the present invention will be described with reference to FIG.

A signal line from the indoor unit 2 is connected to the outdoor unit 1 by a signal line via a terminal plate (connector) 6.
(Outdoor unit control board) 3 is connected to the serial communication circuit. In addition, power is supplied to the compressor 5 from a power supply controlled by a command from the indoor unit 2 via the rectifier circuit 8 and the inverter 9 of the power transistor module.

The control unit (outdoor unit control board) 3 of the outdoor unit 1 which has received the operation command controls the refrigerant control solenoid valve 4 to adjust the room temperature as desired for the indoor unit and to control the outdoor fan motor. The operation of the compressor motor 5 is controlled by the control of the inverter 9.

FIG. 2 is an electric circuit diagram of a main part of a control unit mounted on the indoor unit 2. As shown in FIG. The microcomputer 21 is provided with a switch for setting a basic mode of the air conditioner, an operation display unit, and a circuit for receiving a signal from a remote controller (not shown).

The microcomputer 21 controls the operation of the air conditioner based on a signal sent from the remote controller. Based on the settings of the cooling operation / heating operation / blowing operation, a signal for turning on (energizing) the four-way valve via the terminal 3 of the connector 6A is output to the control unit of the outdoor unit 1 during the heating operation.

Reference numeral 23 denotes a step motor for changing the angle of a wind direction adjusting plate (flap) to change the discharge direction of the conditioned air vertically and horizontally. 22 is the indoor fan 2
This is a motor for driving the first cross flow fan, and its rotation speed is controlled in accordance with the vertical rotation of the wind direction adjusting plate. The drive circuit of the motor 22 is a microcomputer 2
1 is controlled. TH1 and TH2 are temperature sensors, respectively.

FIG. 3 is an electric circuit diagram of a main part of the control unit of the outdoor unit 1. In this figure, the connector 6B is connected to the same terminal number as the connector 6A of the control unit of the indoor unit 2 shown in FIG.

The serial circuit is provided for transmitting signals between the microcomputer 21 of the indoor unit 2 and the microcomputer 31 of the outdoor unit 1. The serial circuit 20 is connected to the indoor unit 2. The outer unit 1 includes a serial circuit 30.

The microcomputer 31 of the outdoor unit 1 receives the operation command from the indoor unit via the serial circuit 30, and controls the operation of the compressor motor 5, the four-way valve switching solenoid RV, and the fan motor 7.

An AC motor is used as the compressor motor 5, and the DC power rectified by the rectifier circuit 8 is controlled by an inverter 9 controlled by a command signal from a microcomputer 31.
Is converted into AC power and supplied. The fan motor 7 is a motor that is operated by being supplied with AC power.

RV is a solenoid for switching a four-way valve,
The state of the four-way valve is switched by energizing. Therefore, when the solenoid RV is energized, the refrigeration cycle performs a heating operation, and when the solenoid RV is deenergized, the refrigeration cycle performs a cooling operation.

TH3, TH4 and TH5 are temperature switches, TH3 detects the outside air temperature, TH4 detects the temperature of the outdoor heat exchanger, and TH5 detects the temperature of the compressor and inputs the temperature to the microcomputer 31. .

In the air conditioner configured as described above, if the power supply voltage supplied to the compressor motor or the like as the power source fluctuates beyond the normal operation range to the protection operation range, the air conditioner is protected. Power supply to the compressor motor etc. must be stopped. This was especially important in foreign countries where power supply was not good.

[0021]

SUMMARY OF THE INVENTION Accordingly, the present invention relates to an operation of such an air conditioner, in which a power supply voltage supplied to a compressor motor or the like, which is a power source, exceeds a normal operation range to a protection operation range. An object of the present invention is to provide a control device for an air conditioner that stops power supply to a compressor motor or the like when it fluctuates and protects equipment.

[0022]

According to a first aspect of the present invention, there is provided a control apparatus for an air conditioner, comprising: means for detecting a power supply voltage of the air conditioner; And means for issuing an instruction to stop the output of the inverter for driving the compressor motor of the outdoor unit when the power supply voltage is out of the normal operation range.

In this way, when the power supply voltage supplied to the compressor motor or the like as a power source fluctuates beyond the normal operation range to the protection operation range, the power supply to the compressor motor or the like is stopped to protect the equipment. Can do it.

According to a second aspect of the present invention, there is provided a control apparatus for an air conditioner, comprising: means for detecting a power supply voltage of the air conditioner; means for determining whether or not the power supply voltage is within a normal operating range; Means for performing a protective operation of the compressor of the indoor unit when the temperature is out of the normal operation range, the means for performing the protective operation includes a means for instructing the output stop of the compressor motor driving inverter during the protective operation, The stop timer measures the operation time, and means for canceling the output stop operation of the inverter when the power supply voltage returns to the normal operation range and the stop timer measures a predetermined time.

Thus, when the power supply voltage supplied to the compressor motor or the like as a power source fluctuates beyond the normal operation range to the protection operation range, the power supply to the compressor motor or the like is stopped to protect the equipment. At the same time, the stop timer of the indoor unit is set to a predetermined time, and unless the stop timer expires, the automatic return is prevented and the power supply stop operation is continued to ensure the indoor unit operation return condition to ensure safe operation. Protective action can be achieved.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The concept of the power supply voltage fluctuation judgment of the present invention will be described with reference to FIG. In FIG. 4A, the control including the protection operation is performed by dividing a power supply voltage supplied to a compressor motor or the like as a power source of the air conditioner into a normal operation range and a protection operation range.

The normal operating range of the power supply voltage is a range of a predetermined + a% and a predetermined -b% with respect to the reference voltage,
The protection operation range is a range of + a% or more with respect to the reference voltage and a range of -b% or less with respect to the reference voltage. This a, b
Is determined according to the power supply situation and the use conditions of the device. For example, in a foreign country, if the reference voltage is 220 VAC, a = 15 and b = 20.

[0028] Therefore, as shown in figure 3 of the operating range 4 (B), when the current supply voltage and V _AC, HI zone V _AC> reference voltage + a% range by each criterion,
Reference voltage + a% ≧ V _AC ≧ reference voltage−b%
D zone, the range of the reference voltage -b%> V _AC can be defined as LOW zone.

Next, an example of an input overvoltage / low voltage detection circuit for detecting a voltage fluctuation of the power supply based on a criterion will be described with reference to FIG. The AC power is rectified by a rectifier circuit 8 and converted into a controlled AC through a switching power converter unit 9 including an inverter and the like.
Supplied to

The output rectified by the rectifier circuit 8 obtains a constant voltage (for example, 5.6 V) with a constant voltage element, and outputs a resistance R3, R4,
R5, the two comparators IC1, IC1,
The reference voltage is input to one input of each of IC2. The power supply voltage is divided by the resistors R1 and R2 and directly input to the other inputs of the comparators IC1 and IC2.

The outputs of the comparators IC1 and IC2 are PC1, P
It is connected to a photocoupler 11 made of C2. PC1,
The PC 2 is connected in series, and the output V _out of an output terminal whose middle point is the output section is supplied to the microcomputer 31 in FIG.

In such an input overvoltage / low voltage detection circuit, two comparators IC1 and IC2 of the comparison circuit 10 are used as shown in FIG.
The zone is determined according to the criterion of (B), and V _AC
If> reference voltage + a%, PC1 of the photocoupler 11 is turned on, PC2 is turned off, and the output _Vout of the output terminal at the connection point becomes VH. Reference voltage + a%
If ≧ V _AC ≧ reference voltage−b%, P of photocoupler 11
C1 is turned on, PC2 is turned on, and the output _Vout of the output terminal at the midpoint of the connection becomes VM. If the reference voltage −b%> V _AC , PC1 of the photocoupler 11 is turned off, PC2 is turned on, and the output _Vout of the output terminal at the midpoint of the connection becomes VL.

The output VH, VM, VL of the output terminal at three levels thus obtained is supplied to the microcomputer 31. The microcomputer 31 constantly monitors (a) the power supply voltage. (B) When the voltage exceeds the normal operation range, the stop timer of the indoor unit 2 is set to x time, and the protection operation is started. (C) During the protection operation, the output of the inverter 9 of the outdoor unit 1 is instructed to stop, or the notification and display are performed, and the stop operation is manually performed. (D) Return of stop operation
When the power supply returns to the normal operation range and the stop timer of the indoor unit 2 has expired, the indoor unit 2 is automatically restored. And the like.

Next, the protection processing operation of the microcomputer 31 when the power supply fluctuates will be described with reference to the processing flow of FIG. When the processing operation starts in step S1, step S2
The power supply voltage level is input at step S3.
It is determined whether or not power supply voltage> reference voltage + a%. If power supply voltage> reference voltage + a% is not satisfied, the process proceeds to step S4.

In step S4, power supply voltage <reference voltage−
b% is determined, and if power supply voltage <reference voltage−b% is not satisfied, that is, reference voltage + a% ≧ V _AC ≧ reference voltage−
If the power supply voltage is within the normal operating range, it is determined in step S5 whether the stop timer of the indoor unit 2 has expired. If the timer has already expired, the normal operation is performed in step S6 of the next stage. And the process returns to step S2 and is repeated.

In step S3, if power supply voltage> reference voltage + a%, the process proceeds to step S7, where x time is set in the stop timer of the indoor unit 2. Actually, x time is set to about 1 to 3 minutes. Then, in step S8, an instruction to stop the output of the inverter 9 of the outdoor unit 1 is issued, or a notification operation is performed and a protection operation of manually stopping the operation is performed, and the process returns to step S2 to repeat the processing.

If it is determined in step S4 that the power supply voltage is smaller than the reference voltage -b%, the process proceeds to step S7.
X time is set to the stop timer of the indoor unit 2.
Actually, x time is set to about 1 to 3 minutes. Then, in step S8, an instruction to stop the output of the inverter 9 of the outdoor unit 1 is issued, or a notification operation and a display are performed to perform a protection operation of manually stopping the operation.
Return processing to step 2 is repeated.

Further, in step S5, if the stop timer of the indoor unit 2 has not yet expired,
In step S8, an instruction to stop the output of the inverter 9 of the outdoor unit 1 is issued, or a notification operation is performed and a protection operation of manually stopping operation is performed, and the process returns to step S2 to repeat the process.

[0039]

As described above, according to the present invention, when the power supply voltage supplied to the compressor motor or the like, which is the power source of the air conditioner, deviates from the normal operation range to the protection operation range, the compressor motor is controlled. Power supply to
As long as the equipment is protected and the indoor unit stop timer counts and the predetermined time is not up, the automatic stop of the output stop operation is prevented, the power supply stop operation is continued, and the indoor unit operation return condition is maintained. And a safe protection operation can be achieved.

A range in which the power supply voltage is equal to or more than a predetermined + a% with respect to the reference voltage and a range in which the power supply voltage is equal to or less than a predetermined -b% with respect to the reference voltage are the protection operation ranges outside the normal operation range. Can be set arbitrarily according to the power supply situation and the usage conditions of the equipment, so that, for example, in a foreign country where the power supply voltage is various, the protection operation against the fluctuation of the power supply voltage is properly performed.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a separate type air conditioner.

FIG. 2 is a control unit of an indoor unit.

FIG. 3 is a control unit of the outdoor unit.

FIG. 4 is an outline of a power supply voltage fluctuation determination according to the present invention.

FIG. 5 is an input overvoltage / low voltage detection circuit according to the present invention.

FIG. 6 is a flowchart of a protection operation process in the microcomputer.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Outdoor unit 2 Indoor unit 3 Outdoor unit control board 4 Solenoid valve for refrigerant control 5 Compressor motor 6 Outdoor / indoor terminal board (connector) 7 Outdoor fan motor 8 Rectifier circuit 9 Power transistor module (inverter) 10 Comparison circuit 11 Optical coupler 20 , 30 Serial circuit device (use side heat exchanger) 21, 31 Microcomputer 22 Indoor fan motor 23 Step motor

Continued on the front page (72) Inventor Hiroshi Yoshida 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Inventor Manabu Ishihara 2-5-2-5 Keihanhondori, Moriguchi-shi, Osaka Inside Sanyo Electric Co., Ltd. (72) Inventor Yuki Takatsu 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Prefecture Inside Sanyo Electric Co., Ltd. (72) Eiji Kawabe 2-5-2 Keihanhondori, Moriguchi-shi, Osaka No. 5 Sanyo Electric Co., Ltd.

Claims (2)

[Claims] A means for detecting a power supply voltage of the air conditioner; a means for determining whether or not the power supply voltage is within a normal operating range; and a compressor motor of the outdoor unit when the power supply voltage is out of the normal operating range. Means for instructing the output of the drive inverter to stop. Means for detecting a power supply voltage of the air conditioner; means for determining whether or not the power supply voltage is within a normal operating range; Means for performing a protection operation,
Means for performing the protection operation, means for instructing the output stop of the compressor motor drive inverter during the protection operation,
An air conditioner comprising: a stop timer for measuring a time of a protection operation; and means for canceling an output stop operation of an inverter when a power supply voltage returns to a normal operation range and the stop timer has counted a predetermined time. Machine control device.