JPH09282023A - Device and method for diagnosing abnormality of control equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the erroneous detection of an abnormal state accomanying the start of diagnosis in the instable state of operating voltage of control equipment in simple configuration even when the operating voltage of the control equipment is higher than that of a controller by starting the diagnosis of the abnormal state after the lapse of prescribed time from the ON of a power source. SOLUTION: A diagnostic means 43 is provided at a controller 40, which is operated at the voltage lower than the operating voltage of control equipment EV so as to control the control equipment EV, and when the power sources of the control equipment EV and the controller 40 are turned on, the abnormal state of the control equipment EV is diagnosed. Then, an inhibiting means 44 is provided for inhibiting the diagnosis by the diagnostic means 43 for the lapse of prescribed inhibition time from the ON of power sources. Thus, even when the operating voltage of the control equipment EV is higher than that of the controller 40 and the stabilization of that operating voltage after the ON of the power source is delayed in comparison with the controller 40, the abnormality diagnosis is started after the lapse of inhibition time from the ON of power sources and the stabilization of operating voltage of the control equipment EV, the erroneous detection of the abnormal state can be surely prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technical field relating to an abnormality diagnosing apparatus and method for control equipment in an air conditioner or the like.

[0002]

2. Description of the Related Art Conventionally, for example, Japanese Patent Laid-Open No. 6-33717.
As disclosed in Japanese Patent No. 4 publication, a microcomputer controls the opening of an electric expansion valve provided in a refrigerant circuit of an air conditioner, and the microcomputer generates a rectangular wave of a specific frequency based on a clock signal. It is known to set the opening control time of the electric expansion valve by this rectangular wave.

[0003]

By the way, a self-diagnosis function is provided in the above microcomputer, and when the microcomputer or the like is turned on, whether or not the control device such as the internal memory or the electric expansion valve is normal is self-diagnostic. You may have to make a diagnosis.

In this case, when the operating voltage of the control device is higher than the operating voltage of the microcomputer, the control device turns on the power.
While rising to the operating voltage according to the state, the microcomputer reaches the operating voltage first and starts self-diagnosis, and as a result, the control device is If there is an abnormal state such as disconnection of the connector or damage to the control device, there is a risk of false detection.

The present invention has been made in view of the above circumstances, and an object of the present invention is to include a control device that operates at a voltage higher than that of the control device (microcomputer) when the power is turned on as described above. When the self-diagnosis is performed by the self-diagnosis, by improving the timing of the self-diagnosis, a simple configuration that does not require a detection circuit etc. to detect the stabilization of the circuit of the control device can be used to erroneously detect the abnormal state of the control device. Is to be able to prevent.

[0006]

In order to achieve the above object, according to the present invention, even when the control device and the control device are powered on, a predetermined time elapses and then the operating voltage of the control device becomes stable. Until then, the control device was not diagnosed.

Specifically, in the invention of claim 1, as shown in FIG. 1, a control device (4) for controlling the control device (EV) by operating at a voltage lower than the operating voltage of the control device (EV).
0), which is equipped with a diagnostic means (43) for diagnosing an abnormal state of at least the control device (EV) when the control device (EV) and the control device (40) are powered on. The target is an abnormality diagnosis device.

A prohibition means (44) for prohibiting the diagnosis by the diagnosis means (43) until a predetermined prohibition time (T) has elapsed since the power supply to the control device (EV) and the control device (40) was turned on. To provide.

With the above-mentioned structure, the abnormality diagnosis of the control device (EV) by the diagnosis means (43) in the control device (40) is prohibited means (44) until a predetermined prohibition time (T) elapses after the power is turned on. The diagnosis is started after the prohibition time (T) has elapsed. Therefore, even if the operating voltage of the control device (EV) is higher than that of the control device (40) and the operating voltage becomes stable after the power is turned on, even if it is delayed as compared with the control device (40), the prohibition time ( After T) has elapsed and the operating voltage of the control device (EV) has reached a stable state, abnormality diagnosis of the control device (EV) will start, and thus the operating voltage of the control device (EV) will be in an unstable state. It is possible to reliably prevent erroneous detection of an abnormal state that accompanies the start of the diagnosis in.

Moreover, since the diagnosis is forcibly prohibited until the prohibition time (T) elapses after the power of the control device (40) is turned on, it is necessary to actually stabilize the operating voltage of the control device (EV). A detection circuit or the like for detecting is unnecessary, and the above-mentioned erroneous detection can be prevented with a simple configuration.

Further, since the erroneous detection of the abnormal state of the control device (EV) can be prevented as described above, the rising of the operating voltage of the control device (EV) should be slowed down rather than earlier than that of the control device (40). Therefore, it is possible to reduce the cost because there is no need for parts or the like to accelerate the rise.

In the invention of claim 2, the control device (E
V) is an electric expansion valve of the air conditioner. This way,
When the electric expansion valve of the air conditioner is controlled by the control device (40) and the abnormal condition of the electric expansion valve is diagnosed when the electric expansion valve and the control device (40) are turned on, The same effect can be achieved.

According to a third aspect of the invention, in the abnormality diagnosing device for a control device according to the second aspect of the invention, a prohibiting means (44) is provided.
The prohibition time (T) is 2 seconds. As a result, the optimum value of the prohibited time (T) can be obtained.

According to a fourth aspect of the present invention, there is provided a control device (EV),
When the control device (40) for controlling the control device (EV) by operating at a voltage lower than the operating voltage of the control device (EV) is powered on, at least the control device (E) is
V) is a method for diagnosing an abnormal state of a control device, wherein the control device (EV) and the control device (40) are turned on at least until a predetermined prohibition time (T) elapses. Diagnosis of an (EV) abnormal condition shall be prohibited. Also in this invention, it is possible to obtain the same operational effect as that of the invention of claim 1.

[0015]

FIG. 6 shows a control system of an induction motor (CM) of a compressor provided in an outdoor unit of an air conditioner according to an embodiment of the present invention. (20) a power conversion circuit for converting 200V three-phase AC power supplied from a power supply (PS) to controlled three-phase AC power,
This power conversion circuit (20) includes a rectifier circuit (21), a smoothing circuit (22), and an inverter circuit (23).
The rectifier circuit (21) includes six diodes (d1),
(D1), ..., And a switching circuit (11)
And a diode module connected to the power supply (PS) via the power supply (PS) for full-wave rectification of the alternating current from the power supply (PS).

The smoothing circuit (22) smoothes the direct current that is full-wave rectified by the rectifying circuit (21), and is provided with a reactor (2L) and a capacitor circuit (2C) having a smoothing capacitor (2C). 2a),
A resistor circuit (2b) having a discharge resistor (2R) is connected between the power supply lines (2P) and (2N). A current transformer (CT), which is a current detector that detects a DC current, that is, a motor current that is a current of the induction motor (CM), is provided on the power supply line (2N) of the smoothing circuit (22). .

Further, the inverter circuit (23) is
A smoothing circuit (22) is a transistor module that converts a smoothed direct current into an alternating current, and includes a three-phase alternating current control power. The transistor module includes a transistor bridge circuit including six power transistors (Tr), (Tr),. Is supplied to an induction motor (CM). Are connected between the emitter and the collector of the power transistors (Tr), (Tr),..., And are connected to these power transistors (Tr), (T2).
r),... are turned ON / OFF by a drive signal of the power control circuit (30).

The power control circuit (30) receives a current signal from the current transformer (CT), and includes a drive circuit (31) and a microcomputer (40). The drive circuit (31) includes power transistors (Tr), (Tr), ...
So that the power transistor (T
Drive signals are output to r), (Tr), ....

On the other hand, the microcomputer (40) is provided with a speed control means (41) and an optimum control means (42). An air conditioning load signal such as the room temperature is input to the speed control means (41), and the induction motor (CM) that is the operating frequency of the compressor is supplied in the speed control means (41) in accordance with the air conditioning load signal. The frequency is derived, and a control signal is output to the drive circuit (31) so as to obtain this supply frequency. That is, the speed control means (41) controls the drive of the inverter circuit (23) so that the supply frequency and the supply voltage of the induction motor (CM) change based on a preset reference voltage frequency characteristic, In other words, the induction motor (CM) is controlled by controlling the supply frequency of the induction motor (CM).
Is output to the drive circuit (31). And this drive circuit (31)
A drive signal is converted into a power conversion circuit (2
0) to the inverter circuit (23).

On the other hand, the optimum control means (42) makes an adjustment signal for adjusting the supply voltage of the induction motor (CM) so that the supply voltage of the induction motor (CM) is minutely changed by a predetermined change amount to minimize the motor current. Output to the drive circuit (31). Then, the drive circuit (31) outputs the drive signal based on the adjustment signal to the inverter circuit (23) of the power conversion circuit (20).
I am trying to output to.

Further, as shown in FIG. 5, the microcomputer (40) is capable of transmitting and receiving signals to and from various devices in addition to the drive circuit (31). Specifically, as a device that transmits a signal to the microcomputer (40), a fin thermistor (Th-thermister) that detects the temperature of each part of the air conditioner is used.
f), detecting a zero-cross point of a power supply voltage waveform serving as a reference point for performing phase control of a heat exchange thermistor (Th-e), an outside air thermistor (Th-a), a discharge pipe thermistor (Th-1), a fan, and the like. Zero cross detection circuit (5
1), protection device input circuit (5
2) The internal and external transmission circuit (54) for transmitting and receiving control signals to and from the indoor unit (53), the reset circuit (55) for issuing a reset signal when the air conditioning operation is stopped, and the operation timing of the microcomputer (40). An oscillator (56) for generating a clock signal for setting is connected to the microcomputer (40). On the other hand, as a device that receives a control signal from the microcomputer (40), in addition to the compressor (COMP),
The outdoor fan (F) and the solenoid valve (S
V) and an electric expansion valve (EV);
4) are connected to the microcomputer (40).

FIG. 4 shows a power supply circuit for supplying an operating voltage to the microcomputer (40) and the electric expansion valve (EV), and (CN) is a three-phase AC power supply having a 200V voltage of 18V.
Is a power supply terminal that is supplied after being converted into a two-phase AC voltage. This terminal (CN) is a 14V composed of an IC that rectifies an 18V AC into a 14V DC and outputs it to a 14V output terminal (V1). 3 terminal guulator (HS1) is connected. Also, this 14V 3-terminal guulator (HS
1) is connected to a 5V 3-terminal guulator (HS2) which is an IC that transforms the voltage from the regulator (HS1) to 5V and outputs it to the 5V output terminal (V2). The 14V output terminal (V1) is connected to the electric expansion valve (EV), and the 5V output terminal (V2) is connected to a microcomputer (40). The electric expansion valve (EV) is for 14V. The 14V direct current voltage generated by the 3-terminal guulator (HS1) is used as the operating voltage, and the microcomputer (40) operates the 5V direct current voltage generated by the 5V 3-terminal guulator (HS2), that is, the electric expansion valve ( The operating voltage is lower than the operating voltage of (EV).

In FIG. 4, (D1) is a power supply terminal (CN).
, And a diode (C1), (C21) connected in series between the 14V 3-terminal guulator (HS1) are connected in parallel between the power supply terminal (CN) and the 14V 3-terminal guulator (HS1). It is a capacitor. In addition, (C2
2) and (C2) are capacitors connected in parallel between the 14V and 5V three-terminal regulators (HS1) and (HS2).

The microcomputer (40) has an abnormal state of the microcomputer (40) itself and the electric expansion valve (EV) when the electric power is supplied to the electric expansion valve (EV) and the microcomputer (40) by the power supply circuit. Diagnostic means (4)
3) (see FIG. 6). That is, the signal processing operation of the microcomputer (40) when the power is turned on will be described with reference to FIG.
Check if the power is turned on. If this determination is “power ON”, YES, the count value t of the timer is reset to t = 0 in step S2, the count value t of the timer is updated to t + 1 in step S3, and the timer is updated in step S4. The count value t is “2
It is determined whether or not a predetermined value corresponding to "second" is exceeded.
When the determination is NO, the process returns to step S3, but when the determination is YES, the process returns to step S5 after diagnosing the abnormal state of the microcomputer (40) itself and the electric expansion valve (EV).

In this embodiment, the above steps S1 and S
5, when the power is turned on, the microcomputer (40)
The diagnostic means (43) for diagnosing the abnormal state of itself and the electric expansion valve (EV) is configured.

Further, in steps S2 to S4, the diagnostic means (43) is set until a predetermined prohibition time (T) (= 2 seconds) elapses from the time when the electric expansion valve (EV) and the microcomputer (40) are turned on. )) Prohibition means (4)
4) is configured.

Therefore, in this embodiment, the control operation of the induction motor (CM) is performed as follows.
That is, when an operation command such as a cooling operation is output from a remote controller (not shown) while the switching circuit (11) is turned on by turning on the power supply (PS), the microcomputer (40) receives the operation command and controls the speed. Means (41)
Outputs a control signal. This control signal is sent to the drive circuit (3
1) receives and outputs a drive signal to the inverter circuit (23), and the power transistors (Tr), (Tr),.
N / OFF.

On the other hand, the three-phase AC power from the power supply (PS) is full-wave rectified by the rectifier circuit (21), converted to DC, smoothed by the smoothing circuit (22), and then smoothed by the inverter circuit (22). 23). And
The six power transistors (Tr), (Tr),... Of the inverter circuit (23) convert DC into AC, and perform PWM modulation to apply a predetermined supply voltage to the induction motor (CM). .

An air conditioning load signal such as room temperature is input to the microcomputer (40), and an induction motor (CM) which is the operating frequency of the compressor corresponding to the air conditioning load signal is input to the speed control means (41). ) Is derived, and the drive circuit (3
A control signal is output to 1). That is, the speed control means (41) controls the drive of the inverter circuit (23) so that the supply frequency and the supply voltage of the induction motor (CM) are changed based on the preset reference voltage frequency characteristic. Is output, and the drive signal is output from the drive circuit (31) to the inverter circuit (23) based on the control signal. As a result, the induction motor (CM) rotates corresponding to the air-conditioning load.

Further, when the induction motor (CM) is rotating, the optimum control means (42) is arranged so that the supply voltage of the induction motor (CM) is minutely changed by a predetermined amount of fluctuation to minimize the motor current. The adjustment signal from the drive circuit (3
1), and based on this adjustment signal, the driving circuit (3)
The drive signal is output from 1) to the inverter circuit (23). Therefore, the induction motor (CM) rotates at the most efficient minimum current value.

In this embodiment, until the predetermined prohibition time (T) (= 2 seconds) elapses from the time when the air conditioner is turned on, the microcomputer (40) abnormally operates its memory or electrically expands it. Diagnosis of valve (EV) abnormality is prohibited,
After that, when the prohibition time (T) has elapsed, the diagnosis of the abnormal state is started. That is, as shown in FIG.
The operating voltage of the electric expansion valve (EV) is 14V and the microcomputer (4
0) is higher than the operating voltage of 5V, and the operating voltage of the expansion valve (EV) stabilizes after the power is turned on, even if it is slower than that of the microcomputer (40), but a predetermined prohibition time (T) has elapsed since the power was turned on. Then, after the operating voltage of the electric expansion valve (EV) becomes stable, the abnormality diagnosis of the expansion valve (EV) is started. As a result, it is possible to reliably prevent erroneous detection of an abnormal state, such as when diagnosis is started when the operating voltage of the electric expansion valve (EV) is in an unstable state during rising. Moreover, a detection circuit or the like for detecting the stabilization of the operating voltage of the electric expansion valve (EV) is completely unnecessary, and the microcomputer (4
Since it is only necessary to change the software in 0), the above erroneous detection can be prevented with a simple configuration.

Further, since the erroneous detection of the abnormal state of the electric expansion valve (EV) can be surely prevented in this way, the microcomputer (40) determines the rising characteristic of the operating voltage of the electric expansion valve (EV).
It can be made gentler than earlier, and there is no need for parts or the like to accelerate its rise, and cost can be reduced.

In the above embodiment, when the electric expansion valve (EV) in the air conditioner is controlled by the microcomputer (40), the abnormality of the electric expansion valve (EV) is diagnosed. Not only the electric expansion valve (EV) of the air conditioner, but also other control devices are controlled by a control device that operates at a voltage lower than its operating voltage, and at least the abnormal state of the control device is diagnosed when the power is turned on. In that case, the present invention can be applied.

[0034]

As described above, according to the invention of claim 1 or 4, the control device is controlled by the control device which operates at an operating voltage lower than its operating voltage, and when the power of the control device and the control device is turned on. At least when the control device diagnoses an abnormal state of the control device, the operating voltage of the control device is higher than that of the control device because the diagnosis of the abnormal state is started after a predetermined time has passed since the power was turned on. Even if the stable state after power-on is delayed compared to the control device, with a simple configuration, it is possible to prevent erroneous detection of an abnormal state accompanying the start of diagnosis in the unstable state of the operating voltage of the control device, It is possible to reduce the cost by slowing the rise of the operating voltage of the control device and eliminating the need for parts or the like for speeding the rise.

According to the second aspect of the present invention, since the control device is the electric expansion valve of the air conditioner, the electric expansion valve of the air conditioner and the abnormal state of the electric expansion valve are diagnosed when the control device is powered on. In this case, the same effect as the invention of claim 1 can be obtained.

According to the third aspect of the invention, by setting the prohibition time to 2 seconds, the optimum value of the prohibition time can be obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of the present invention.

FIG. 2 is a flowchart showing a signal processing operation for abnormality diagnosis performed at power-on in the microcomputer according to the embodiment of the present invention.

FIG. 3 is a characteristic diagram showing a rising state of operating voltages of a microcomputer and an electric expansion valve when power is turned on.

FIG. 4 is an electric circuit diagram showing a power supply circuit for a microcomputer and an electric expansion valve.

FIG. 5 is a block diagram showing a device connected to a microcomputer.

FIG. 6 is a control circuit diagram of an induction motor for a compressor in an air conditioner.

[Explanation of symbols]

 (40) Microcomputer (control device) (43) Diagnostic means (44) Inhibition means (EV) Electric expansion valve (control equipment) (T) Inhibition time

Claims (4)

[Claims] 1. A control device (40) for controlling a control device (EV) by operating at a voltage lower than an operating voltage of the control device (EV), the control device (EV) and the control device (40). An abnormality diagnosis device for a control device, comprising at least a diagnosis means (43) for diagnosing an abnormal state of the control device (EV) when the power is turned on, the control device (EV) and the control device (40). (4) is provided with a prohibiting means (44) for prohibiting the diagnosis by the diagnosing means (43) until a predetermined prohibition time (T) elapses after the power is turned on. 2. The abnormality diagnosis device for a control device according to claim 1, wherein the control device (EV) is an electric expansion valve of an air conditioner. 3. The abnormality diagnosis device for a control device according to claim 2, wherein the inhibition time (T) of the inhibition means (44) is 2 seconds. 4. A control device (EV) and the control device (E)
V) operating at a voltage lower than the operating voltage of the control device (E
A method for diagnosing an abnormal condition of at least the control device (EV) when the power is turned on to the control device (40) for controlling V). A method for diagnosing abnormalities in a control device, wherein diagnosis of an abnormal state of at least the control device (EV) is prohibited until a predetermined prohibition time (T) has elapsed since the power to the control device (40) was turned on.