KR19990070381A - Temperature control device and method of compressor driving motor - Google Patents

Abstract

In an outdoor unit of an inverter air conditioner having a microcomputer, a first PCB equipped with a temperature sensing unit and a second PCB equipped with an inverter driving unit and an inverter power unit, a temperature for sensing a temperature change of the first PCB and the second PCB Compressor drive motor that receives the output signal from the thermistor and the inverter power unit mounted on the second PCB to drive and prevents distortion of the current waveform due to temperature rise or damage caused by overcurrent and at the same time improves the efficiency of the compressor drive motor. Can be increased.

Description

Temperature control device and method of compressor driving motor

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inverter air conditioner, and more particularly, to a compensation control method for a temperature difference between a compressor driving control device and a driving circuit of an inverter air conditioner.

In general, a device that converts electrical alternating current into direct current or inversely converts direct current into alternating current is called a converter or an inverter, and an air conditioner using the same is called an inverter air conditioner.

In this way, the inverter air conditioner converts a constant AC voltage through rectification and then converts it into AC again to convert a frequency or voltage according to cooling load conditions. For example, when applied to a compressor, the rotation speed changes according to the frequency change. It is possible to vary the cooling capacity, thereby enabling power saving cooling operation of low power consumption.

In addition, the inverter air conditioner protects the system when the DC current is rapidly increased due to the increase of the compressor pressure when the indoor temperature and the outdoor temperature exceed the set temperature range, or when the total current increases to reach the DC peak voltage. To reduce the compressor operation frequency or stop the compressor and at the same time stop the drive of the outdoor fan after a certain time.

1 is a block diagram showing the configuration of an inverter air conditioner according to the prior art, Figure 2 is a detailed circuit diagram of the inverter air conditioner according to the prior art.

1 is an electrical connection diagram showing an example of a configuration of an inverter air conditioner composed of an indoor unit and an outdoor unit, wherein the indoor unit has a low temperature heat exchanged by an indoor temperature sensor 110 and an indoor heat exchanger that senses an indoor temperature. It consists of an indoor fan motor 120 for blowing airflow into the room, and an indoor microcomputer 130 that is equipped with an indoor fan motor control, a temperature calculation and a timer function, and outputs a control signal for controlling a load according to a set program. do.

The outdoor unit controls an inverter output frequency by an outdoor temperature sensor 210 for sensing an outdoor temperature, an outdoor fan motor 220 for cooling an outdoor heat exchanger to increase heat exchange efficiency, and a control signal of the indoor unit microcomputer 130. Passing through the outdoor unit microcomputer 230, the control unit of the outdoor unit microcomputer 230 to drive the compressor driving the TR 240, and the A / D converter 250 in accordance with the drive of the TR driving unit 240. By converting the direct-current DC power converted by commercial power to AC again, the inverter unit 260 for driving the compressor and the refrigerant of the cooling cycle by forcibly compressed by the AC power applied from the inverter unit 260 to circulate Compressor 270, DC-peak detector 280 for detecting the voltage and current fluctuating in accordance with the rise of the overload, and over-current detector 290 for detecting the over-current is cooled by a predetermined program Performing a large, or heating cycle will be the heating / cooling.

The inverter air conditioner according to the prior art has the following problems.

First, since there is no compensating control method for the temperature deviation of photocouplers and transistors, the motor efficiency decreases due to distortion of the three-phase AC waveform applied to the compressor motor.

Second, the power device is damaged due to the lack of dead time between the top insulated gate type bipolar transistor IGBT and the bottom insulated gate type bipolar transistor IGBT.

The present invention has been made to solve the above problems, it is mounted on a heat sink equipped with a power device and a driving circuit, and equipped with a temperature sensor on the top of the heat sink to determine the heat sink temperature by the insulation gate type bipolar transistor (IGBT) and SUMMARY OF THE INVENTION An object of the present invention is to provide a compressor drive control apparatus for an inverter air conditioner for compensating and controlling a temperature deviation of a drive circuit of an IPM, and a temperature deviation compensation control method thereof.

1 is a view showing a typical inverter air conditioner

2 is a detailed circuit diagram of an inverter air conditioner according to the prior art.

3 is a block diagram showing a compressor driving apparatus according to the present invention.

4 is a flow chart showing a temperature deviation correction method according to the present invention

Explanation of symbols for main parts of the drawings

20: first PCB 21: heat sink temperature detection unit

22: compressor upper plate temperature detection unit 23: outdoor temperature detection unit

24: outdoor unit microcomputer 25: photo coupler

30: second PCB 31: temperature thermistor

32: inverter drive unit 33: inverter power unit

40: compressor driving motor

The present invention relates to an inverter air conditioner, comprising: a microcomputer, a first PCB equipped with a temperature sensing unit, and an outdoor unit of an inverter air conditioner including a second PCB equipped with an inverter driving unit and an inverter power unit, wherein the first PCB and A temperature thermistor for detecting a temperature change of the second PCB, and a compressor drive motor for receiving and driving the output signal of the inverter power unit mounted on the second PCB is characterized by.

Hereinafter, with reference to the accompanying drawings as follows.

2 is a block diagram showing a compressor driving motor control apparatus of the inverter air conditioner according to the present invention, Figure 3 is a circuit diagram showing a control circuit of the inverter air conditioner according to the present invention.

As shown in FIG. 2, only the first PCB 20, the second PCB 30, and the compressor driving motor 40 of the outdoor unit circuit of the inverter air conditioner having the outdoor unit and the indoor unit are illustrated.

The first PCB 20 is a heat sink temperature detection unit 21 for detecting the temperature of the heat sink, a compressor upper temperature detection unit 22 for detecting the temperature of the upper end of the compressor, and an outdoor temperature detection unit for detecting the outdoor temperature ( 23) and an outdoor unit microcomputer 24 that controls the entire outdoor unit.

The second PCB 30 includes a temperature thermistor 31, an inverter power element driver 32, and an inverter power unit 33.

The outdoor unit configured as described above will be described with reference to FIG. 3.

First, the inverter pulse width modulation (PWM) waveforms U, V, W, X, Y, and Z waveforms are output from the outdoor unit microcomputer 24, and the pulses are output through the resistor R1, which is a photocoupler PC1. And the resistors R2 to R6 turn on / off the transistor Q1.

When the transistors Q1 are turned on and off in a complementary relationship and the transistors Q1 are turned on, they are distributed to the resistors R8 and R9 so that the first insulated gate type bipolar transistor IGBT1 is turned on and the compressor motor is turned on. The current flows to U phase of. Then, the fifth and sixth insulating gate type bipolar transistors IGBT5 and IGBT6 on the bottom side are driven so that current flows in the U phase and the Y, Z phase among the three phases.

Thereafter, transistor Q3 is turned on, and transistor Q2 is turned off to operate to reduce switching off time of insulated gate type bipolar transistor IGBT through diode D1 and resistor R7.

However, since the on-voltage due to the temperature rise of the transistor Q1 decreases due to the temperature change of the current transfer ratio CTR of the photocoupler PC1, the top IGBT and the bottom IGBT are lowered. As a result of the ARM SHORT phenomenon, the IGBT is damaged and there is a risk of fire. In contrast, the current transfer ratio (CTR) is lowered in the narrow pulse width band and the three-phase current waveform is distorted.

Therefore, the present invention determines the temperature deviation of the heat sink, the heat sink temperature is divided into zero, 25 degrees (C), 80 degrees, 100 degrees or more by controlling the carrier frequency and dead time of the compressor motor by the temperature deviation Reward

First, at a temperature below zero, the dead time is set short, and the carrier frequency is set as large as ∇F for control.

This is because, when the temperature of the photocoupler PC1 is low, the switching delay is small. Therefore, even if the dead time is controlled small, there is no problem in operation. Therefore, the carrier frequency can also be controlled quickly, so that a clean current waveform can be formed by speeding it up.

4 is a flowchart illustrating a temperature deviation correction method according to the present invention.

Referring to FIG. 4, in the inverter air conditioner having the first and second PCBs, it is determined whether the temperature of the second PCB is 0 ° C. or less (S1), and the temperature of the second PCB is 0 according to the determination result. If it is less than or equal to ° C, the dead time DEADTIME is set as short as ∇T, the carrier frequency is set as large as ∇F (S2).

According to the determination result, when the temperature of the heat sink is 0 ° C. or more, the dead time DEADTIME is set as long as ∇T and the carrier frequency is set as small as ∇F (S3).

According to the present invention, as the temperature increases, the dead time is increased and the carrier frequency is decreased, thereby preventing the power device IGBT from being distorted due to the temperature rise or damage caused by overcurrent, and increasing the efficiency of the compressor driving motor. .

Claims (3)

In an outdoor unit of an inverter air conditioner having a microcomputer, a first PCB equipped with a temperature sensing unit and a second PCB equipped with an inverter driving unit and an inverter power unit, A temperature thermistor for detecting a temperature change of the first PCB and the second PCB; And a compressor driving motor configured to receive and drive an output signal of an inverter power unit mounted on the second PCB. The method of claim 1, The temperature thermistor is a temperature control device of the compressor drive motor, characterized in that mounted to the second PCB. In the inverter air conditioner with a heat sink, Determining whether the temperature of the heat sink is 0 ° C. or less; Setting a dead time as short as 이하 T and setting a carrier frequency as large as ∇F when the temperature of the heat sink is 0 ° C. or less according to the determination result; And if the temperature of the heat sink is greater than or equal to 0 ° C., the dead time is set as long as ∇T and the carrier frequency is set as small as ∇F.