KR19980086245A - Compressor Controller of Air Conditioner - Google Patents

Abstract

The present invention relates to a compressor control apparatus for an air conditioner, comprising: converter means for converting AC input power supplied from an AC power source into a DC power source, and a three-phase AC power source having a desired frequency by receiving the DC power converted by the converter means; In the air conditioner composed of an inverter means for converting to a heat exchanger, a compressor rotating by a three-phase AC power output from the inverter means, the temperature sensing means for sensing the outdoor temperature, and the outside temperature detected by the temperature sensing means It consists of control means for varying the operating frequency of the compressor before rising from the starting frequency to the set frequency so as to increase the amount of compressor lubricating oil when the compressor is operated at low temperature. To solve the problem of lubrication caused by the sudden increase in the rotational speed of the compressor when operating the machine, Other satisfies your desire to look forward to heating operation.

Description

Compressor Controller of Air Conditioner

The present invention relates to an inverter air conditioner for driving a compressor by varying a frequency, and more particularly, to a compressor control device of an air conditioner that increases reliability of a compressor during winter use of an air conditioner.

In general, the conventional air conditioner, as shown in Fig. 1, the converter unit 3 for converting the AC input power supplied from the AC power source stage 1 to the DC power, and the DC converted in the converter unit 3 A power supply unit 5 for receiving power and converting it into a predetermined DC voltage required for driving the air conditioner (the microcomputer driving power supply of DC 5V and the load driving power supply of DC 12V) and the DC power output from the power supply unit 5; The controller 7 which initializes the air conditioner by receiving a voltage and outputs an inverter driving signal by setting the operating frequency of the compressor 13 according to the outdoor condition and the indoor unit's instruction, and the operation set by the controller 7. According to a drive signal output from the controller 7 to rotate the compressor 13 according to the frequency, a power-transistor (not shown) is alternately turned on or turned off and output from the converter unit 3. It is composed of an inverter unit 11 for converting the DC power into three-phase AC power.

In the air conditioner for both heating and cooling as configured above, when the AC input power is supplied, the AC input power is converted into the DC power in the converter unit 3, and the converted DC power is input to the power supply unit 5 to provide air conditioning. It is converted into a microcomputer driving power supply of DC 5V and a load driving power supply of DC 12V necessary for driving of the machine and supplied to the control unit 7 and the inverter unit 11.

Therefore, the control unit 7 receives a DC voltage (microcomputer driving power) output from the power supply unit 5 to initialize the air conditioner.

At this time, when the user operates the key operation unit provided on the control panel of the remote controller or the indoor unit, inputs the desired operation mode and the set temperature, and turns on the operation key, the controller 7 controls the compressor according to the outdoor condition and the indoor unit. Set the operation frequency of 13) to output the inverter drive PWM signal to the inverter drive unit (9).

Accordingly, the inverter driver 9 amplifies the PWM signal output from the controller 7 to alternately turn on or turn off six power transistors (not shown) of the inverter unit 11 to convert the converter unit 3. When the DC power output from the inverter is converted into a three-phase AC power and outputted, the compressor 13 rotates by the three-phase (u-phase, v-phase, w-phase) AC power output from the inverter section 11.

That is, the inverter unit 11 supplies the set frequency of the compressor 13 and the corresponding voltage to the compressor 13 in response to the cooling or heating capacity required for the operation of the air conditioner, thereby supplying the compressor 13 at a desired set frequency. Rotate

When the compressor 13 rotates, the refrigerant is heated at the time of heating, as shown by the dotted line (-) in FIG. 2, the compressor 13 → the four-way valve 15 → the indoor heat exchanger 17 → the expansion valve 19. ), A refrigeration cycle circulated in the order of heating expansion valve 21 → outdoor heat exchanger 23 → four-way valve 15 → compressor 13.

On the other hand, during cooling, as the refrigerant is shown by the solid line (→) in FIG. 2, the compressor 13 → the four-way valve 15 → the outdoor heat exchanger 23 → the one-way valve 25 → the expansion valve 19 → It forms a refrigeration cycle circulated in the order of the indoor heat exchanger (17) → four-way valve (15) → compressor (13).

By the way, in such a conventional air conditioner, as shown in Fig. 5A regardless of the state of the compressor 13, it is linear from the starting frequency fl to the desired set frequency f2 at a constant speed. The operating frequency is increased, so there is no problem in cooling operation. However, in one-way operation, when the air conditioner is left for a long time at outdoor temperature below zero, the operating lubricant for the purpose of lubricating the compressor 13 is frozen. There was a problem in that the cycle could not be cycled quickly so that the compressor 13 could not be lubricated properly for a certain period of time.

Accordingly, the present invention has been made to solve the above problems, solve the lubrication problem caused by the rapid increase in the rotation of the compressor when operating the air conditioner after leaving the compressor for a long time at a low temperature below zero, and fast heating It is an object of the present invention to provide a compressor control apparatus of an air conditioner that satisfies a user's desire to operate.

In order to achieve the above object, a compressor control apparatus of an air conditioner according to the present invention includes a converter means for converting AC input power supplied from an AC power source into a DC power source, and receiving the DC power converted from the converter means to a desired frequency. An air conditioner comprising an inverter means for converting into a three-phase AC power source, a compressor rotating by a three-phase AC power source output from the inverter means, comprising: temperature sensing means for sensing an outdoor temperature, and sensing by the temperature sensing means; And a control means for varying the operating frequency of the compressor before the temperature rises from the starting frequency to the set frequency so that the amount of the compressor lubricating oil is increased when the compressor starts at low temperature.

1 is a compressor control block diagram of a conventional air conditioner;

2 is a cooling and heating cycle of a general air conditioner,

3 is a control block diagram of a compressor control apparatus of an air conditioner according to an embodiment of the present invention;

Figure 4 is a drive circuit diagram of a compressor applied to the present invention.

5 is a start pattern diagram of a compressor applied to the present invention;

Figure 6 is a view showing the results of the start test of the compressor in a low temperature state in accordance with the start pattern of the compressor according to the present invention.

Explanation of symbols for main parts of the drawings

30 converter means 31 compressor

35 power supply means 40 control means

45: inverter drive means 50: inverter means

55: temperature sensing means

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

As shown in Figs. 3 and 4, the converter means 30 rectifies and smoothes the AC input power supplied from the AC power supply stage 1 to convert it into DC power, and the power supply means 35 converts the converter means 30. Is a SMPS (Switching Mode Power Supp1y) that receives the converted DC power and converts the DC power into a predetermined DC voltage (DC 5V microcomputer driving power supply, DC 12V load driving power supply) required for driving the air conditioner.

The control unit 40 receives the DC voltage output from the power supply unit 20 to initialize the air conditioner, and operates the optimum compressor 31 based on the outdoor unit and the frequency or indoor unit state instructed by the indoor unit. A microcomputer that outputs an inverter driving PWM signal by setting a frequency, and the inverter driving means 45 rotates from the control means 40 to rotate the compressor 31 in accordance with the operating frequency set by the control means 40. This is a power-transistor driver circuit (PTR DRlVER) that amplifies the output PWM signals PWM1 to PWMM6 to inverter drive signals.

In addition, the inverter means 50 alternately turns or turns off the six power transistors TR1 to TR6 according to the drive signal output from the inverter driving means 45 to output from the converter means 15. The DC power to be converted into a three-phase (u-phase, v-phase, w-phase) AC power of a variable frequency and variable voltage corresponding to the set frequency of the compressor 31 and output to the compressor 31, the temperature sensing means ( 55 senses the temperature of the compressor 31 and outputs it to the control means 40 so as to grasp the outdoor temperature state when the compressor 31 starts up.

Hereinafter, the effect of the compressor control device of the air conditioner configured as described above will be described.

First, when power is applied to the air conditioner, the AC input power supplied from the AC power source 1 is rectified and smoothed by the converter means 30 to convert into DC power, and the DC power converted by the converter means 30. Is converted into a microcomputer driving power supply of DC 5V and DC 12V load driving power required for driving the air conditioner and outputted to the control means 40 and the inverter means 45.

Therefore, the control means 40 receives the DC voltage (microcomputer drive power) output from the power supply means 35 to initialize the air conditioner.

At this time, when the user inputs the desired operation mode by operating the key operation unit provided on the control panel of the remote controller or the indoor unit, and then turns on the operation key, the control means 40 controls the compressor 31 according to the outdoor condition and the indoor unit's instruction. The driving frequency is determined and the PWM signal for inverter driving is output to the inverter driving means 45.

Accordingly, the inverter driving means 45 amplifies the PWM signal output from the control means 40 to alternately turn on or turn off the six power transistors TR1 to TR6 of the inverter means 50 to convert the converter. When the DC power output from the means 30 is converted into three-phase AC power and outputted, the compressor 31 is started by the three-phase (u-phase, v-phase, w-phase) AC power output from the inverter means 50. do.

When the compressor 31 starts, conventionally, as shown in Fig. 5A, the operating frequency of the compressor 31 increases from the starting frequency fl to the set frequency f2 at a constant speed. In the present invention, as shown in Figs. 5B to 5D, the holding frequency Ho1d region which stays at a constant frequency for a while before rising from the starting frequency fl to the setting frequency f2 is set to the set frequency f2. And one or more between the start frequency fl and a plurality of patterns as shown in Figs. 5A to 5D are stored in the control means 40.

At this time, the number of the starting frequency fl and the holding frequency f3 and the holding frequency f3 and the holding time tl can be determined experimentally according to each air conditioner or other various conditions.

At this time, the temperature sensing means 55 senses the temperature of the compressor 31 to grasp the outdoor temperature state at the time when the compressor 3l is started.

Accordingly, the control means 40 selects an appropriate pattern according to the temperature of the compressor 31 among the plurality of patterns stored when the compressor 31 is left for a long time in a low temperature state and needs to be started at a low temperature. 31).

If the temperature of the compressor 31 is appropriate for the pattern of Fig. 5B, the operation is started at the starting frequency f1 and maintained at a constant speed at the intermediate frequency f3 for a predetermined time tl. The device 40 goes to the set frequency f2 determined by the means 40 and performs normal operation.

In addition, if the temperature of the compressor 31 is appropriate for the pattern of Fig. 5C, the operation starts at the starting frequency fl and is maintained at a constant speed at the intermediate frequency f3 for a predetermined time. After rising to f4) and increasing the circulation amount of the refrigerant for a while, the control unit 40 goes to the set frequency f2 determined by the control unit 40 to perform normal operation.

In addition, if the temperature of the compressor 31 is appropriate for the pattern of Fig. 5D, the operation starts at the starting frequency fl, is maintained at a constant speed at the intermediate frequency f3, and then the higher frequency ( After rising to f4) to increase the circulation amount of the refrigerant for a while, it is lowered to the intermediate frequency f3 and operated, and then to the higher frequency f4 to increase the circulation amount of the refrigerant again, and then the control means 40 Go to the set frequency (f2) determined in) and perform normal operation.

Meanwhile, in the present invention, a plurality of holding frequencies may be set in addition to the holding frequencies f3 and f4 of FIGS. 5A to 5D to increase or decrease the operating frequency, and the holding time or the frequency value of the holding frequency may be changed. May be controlled in real time by the control means 40, or may be input and operated in a pattern preset by the product developer.

Thus, when applied to the compressor 31 of the air-conditioning combined capacity variable air conditioner, the lubrication reliability of the lubricant of the compressor 31 becomes high compared with the operation in the prior art.

The test result of lubrication reliability is that the sight glass which can see the inside is attached to the lower part of the compressor 31 where the lubricating oil is collected and the amount of lubricating oil is measured by starting time. There exists a time to descend | fall to Z plane or less, and the comparison result is as shown in FIG.

FIG. 6 is a diagram showing the amount of lubricating oil present in the compressor 31 when the compressor 31 is started by applying the starting patterns of FIGS. 5B and 5D. It should be greater than or equal to the Z plane, (D) the starting pattern may be that the amount of lubricating oil present in the compressor 31 is less than the (B) starting pattern.

As described above, according to the compressor control apparatus of the air conditioner according to the present invention, after the compressor is prevented for a long time at a low temperature below zero, the lubrication problem caused by the rapid increase in the rotational speed of the compressor is solved when the air conditioner is operated. Therefore, there is an effect that can satisfy the needs of users who expect fast heating operation.

Claims (3)

A converter means for converting AC input power supplied from an AC power source into a DC power source; an inverter means for receiving a DC power converted from the converter means and converting the AC power into a three-phase AC power of a desired frequency; and 3 outputted from the inverter means. In an air conditioner composed of a compressor rotating by a phase AC power source, Temperature sensing means for sensing outdoor temperature; And a control means for varying the operating frequency of the compressor before the temperature rises from the starting frequency to the set frequency so that the amount of the compressor lubricant increases when the outdoor temperature sensed by the temperature sensing means starts the compressor at low temperature. Compressor control device of the air conditioner. The compressor control of the air conditioner according to claim 1, wherein the control means stores a start pattern of the compressor in which at least one sustain frequency region is set for a predetermined time between a start frequency and a set frequency. Device. The compressor control apparatus according to claim 1 or 2, wherein the control means controls the holding time or the frequency value of the holding frequency according to the outdoor temperature.