KR100371193B1 - Driving control method of refrigerator using reciprocating compressor - Google Patents

Abstract

The present invention relates to an operation control method of a refrigerator using a reciprocating compressor, in which the reciprocating compressor is operated under optimal conditions at all times by actively coping with a load change caused by a change in the refrigerator and the surrounding environment. To this end, the present invention, in the refrigerator employing a reciprocating compressor in which the piston is variable in the vertical movement by the applied voltage according to the stroke command value to adjust the cooling force, the current applied to the motor is compared with the previously detected current Detecting a first current peak value of TDC = 0; A second step of setting a time for redetecting an optimal operating condition of TDC = 0 based on the initial current peak detection time of the first step to a predetermined value; A second step of determining whether a predetermined time has elapsed while operating the reciprocating compression unit by controlling the on / off of the triac with the switching control signal corresponding to the current peak value of the first step; As a result of the determination of the second step, when a predetermined time has elapsed, a fourth step of detecting a current peak value of TDC = 0 again and controlling the operation of the reciprocating compression unit with a switching control signal at the current peak value.

Description

Operation control method of refrigerator using reciprocating compressor {DRIVING CONTROL METHOD OF REFRIGERATOR USING RECIPROCATING COMPRESSOR}

The present invention relates to an operation control method of a refrigerator using a reciprocating compressor. In particular, the present invention relates to a method of controlling a refrigerator using a reciprocating compressor in which a reciprocating compressor is always operated under optimum conditions by actively dealing with load fluctuations caused by changes in the refrigerator and the surrounding environment. It relates to an operation control method of a refrigerator.

In general, a reciprocating compressor generates a torque by interrupting the power supplied to a coil wound around a multi-phase stator by using a switching element. By sequentially changing the excitation state between the rotor and the stator, The forward rotational torque can be generated by the suction force.

If the specific excitation state is not changed, the rotor can be stopped at a predetermined position, and various drive control that can generate reverse power by controlling the phase of the input pulse signal applied to the switching element based on the maximum inductance shape. As is possible, it is applied to electronic products requiring direction control.

In particular, the reciprocating compressor used in the refrigerator or the air conditioner can vary the compression ratio by the voltage applied to the motor, and thus has the advantage of controlling the cooling power according to the user's intention. It will be described in detail with reference to one drawing.

1 is a block diagram showing a configuration of an operation control device of a general reciprocating compressor. As shown in FIG. 1, the piston changes the stroke in vertical motion by the voltage applied to the internal motor according to the stroke command value. A reciprocating compression unit (L.COMP) for adjusting; A voltage detector (30) which detects a voltage generated in the reciprocating compression section (L.COMP) as the stroke is increased by an applied voltage; A current detector 20 which detects a current applied to the reciprocating compressor L.COMP as the stroke is increased by an applied voltage; A microcomputer (40) for calculating a stroke from the voltage and current detected by the voltage detector (30) and the current detector (20), comparing the stroke with a stroke command value, and outputting a switching control signal accordingly; In accordance with the switching control signal of the microcomputer 40, it consists of an electrical circuit section 10 for interrupting the AC power to the triac (Tr1) to apply a voltage to the reciprocating compression section (L.COMP), and thus The operation of the conventional apparatus will be described.

First, the reciprocating compression section (L.COMP), the piston is moved up and down by the applied voltage according to the stroke command value set by the user, thereby the stroke is variable to adjust the cooling force.

Meanwhile, the stroke of the triac Tr1 of the electric circuit unit 10 is increased due to a long turn-on period due to the switching control signal of the microcomputer 40, wherein the motor M of the reciprocating compressor L.COMP is increased. The voltage and the current applied to the) are detected by the voltage detector 30 and the current detector 20, and applied to the microcomputer 40.

Then, the microcomputer 40 calculates a stroke using the applied voltage and current detected from the voltage detector 30 and the current detector 20, and compares the stroke with the stroke command value and accordingly switches the control signal. Outputs

That is, when the calculated stroke is smaller than the stroke command value, the microcomputer 40 outputs a switching control signal for lengthening the on-cycle of the triac Tr1, thereby converting the voltage applied to the reciprocating compressor L.COMP. Increase.

Unlike the above, when the calculated stroke is larger than the stroke command value, the microcomputer 40 outputs a switching control signal for shortening the on-cycle of the triac Tr1 and is applied to the reciprocating compression unit L.COMP. Reduce the voltage.

However, since the reciprocating compressor operating as described above has a nonlinearity in which the mechanical motion characteristics are severe, there is a problem that precise control is impossible with a linear control method that does not take into account the nonlinearity.

The present invention has been made in order to solve the above problems, the load fluctuation occurs according to the change of the refrigerator and the surrounding environment, so the optimum operating condition of TDC = 0 again is detected every predetermined time and the reciprocating compressor as the operating condition It is an object of the present invention to provide a method for controlling the operation of a refrigerator using a reciprocating compressor for efficiently operating a refrigerator by operating a.

1 is a circuit diagram showing a configuration for an operation control apparatus of a conventional reciprocating compressor.

Figure 2 is a circuit diagram showing the configuration of the apparatus to which the operation control method of the refrigerator using the reciprocating compressor of the present invention is applied.

FIG. 3 is a diagram showing a current waveform as the duty ratio of the switching control signal is increased in FIG. 2; FIG.

4 is a view showing a change in the current value according to the load change of the refrigerator in FIG.

The present invention for achieving the above object, in the refrigerator employing a reciprocating compressor that adjusts the cooling force by varying the stroke in the vertical movement of the piston by the applied voltage according to the stroke command value, transfer the current applied to the motor A first step of detecting an initial current peak value of TDC = 0 compared to the current detected at; A second step of setting a time for redetecting an optimal operating condition of TDC = 0 based on the initial current peak detection time of the first step to a predetermined value; A second step of determining whether a predetermined time has elapsed while operating the reciprocating compression unit by controlling the on / off of the triac with the switching control signal corresponding to the current peak value of the first step; As a result of the determination of the second step, if a predetermined time has elapsed, a current peak value of TDC = 0 is detected again, and a fourth step of controlling operation of the reciprocating compression unit using a switching control signal at the current peak value is performed.

Hereinafter, the operation and effect of the operation control method of the refrigerator using the reciprocating compressor according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 is a circuit diagram showing the configuration of an apparatus to which the operation control method of a refrigerator using the reciprocating compressor of the present invention is applied, and as shown therein, a current detecting unit 20 for detecting a current applied to a motor; A current peak detection unit (100) for comparing the detected current of the current detection unit (20) with a previously detected current and outputting a current peak detection signal accordingly; A microcomputer 40 for outputting a switching control signal so that the current peak value is maintained when the current peak detection signal is input from the current peak detection unit 100; In accordance with the switching control signal of the microcomputer 40, it consists of an electric circuit section 10 for interrupting the AC power to the triac (Tr1) to apply a voltage to the reciprocating compression section (L.COMP). The operation of the invention will be described.

First, the reciprocating compression section L.COMP moves the piston up and down by the stroke voltage according to the stroke command value set by the user, thereby adjusting the cooling force by varying the stroke.

That is, when the triac Tr1 of the electric circuit unit 10 increases the stroke due to the longer turn-on period according to the switching control signal of the microcomputer 40, the reciprocating compression unit L.COMP Driven.

At this time, the current detection unit 20 detects the current applied to the reciprocating compression unit (L.COMP) and applies it to the current peak detection unit 100, accordingly, the current peak detection unit 100 is the current detection unit ( 20) receives the detection current from the current and compares it with the previous detection current and outputs the current peak detection signal accordingly, that is, the current peak detection unit 100 compares the current detection current with the previous detection current, and detects the previous detection result. If the current is larger than the current detection current, the point of time is recognized as the current peak value and the current peak detection signal is output accordingly.

Then, the microcomputer 40 receives the current peak detection signal and transmits a switching control signal having a duty ratio corresponding to the point in time at which the current peak detection signal is input to the electric circuit unit 10 so that the peak value of the current waveform is maintained. Is authorized.

Accordingly, the electric circuit unit 10 regulates the AC power to the triac Tr1 by the switching control signal of the microcomputer 40 to apply a voltage to the reciprocating compression unit L.COMP, thereby Controls the operation of the L.COMP.

3 shows a change in the current waveform as the duty ratio of the switching control signal is increased. It can be seen from the experiment that the section in which the peak value of the current waveform occurs is a point where the TDC is '0'.

Here, the load applied to the reciprocating compressor is changed as shown in FIG. 4 according to the change of the surrounding environment of the refrigerator. In order to efficiently operate the refrigerator, the present invention detects an initial current peak value of TDC = 0 and detects the initial current peak. Based on the current peak detection time, the predetermined time is set for detecting the current peak value of TDC = 0. Then, the reciprocating compressor (L.COMP) is operated by the switching control signal at the initial current peak value. When the predetermined time elapses, a current peak value of TDC = 0, which is an optimum operating condition, is detected again, and the operation of the reciprocating compressor is controlled by a switching control signal having a duty ratio corresponding to the current peak value.

The present invention will be described in more detail. First, the time for detecting the initial current peak value of TDC = 0, which is the optimum operating condition, and the redetection of the current peak value of TDC = 0 based on the initial current peak value, are set to a predetermined value. do.

Thereafter, the reciprocating compression unit L.COMP is driven while controlling the on / off of the triac Tr1 with the switching control signal at the initial current peak value.

Then, the operation control of the reciprocating compression section (L.COMP), and if the operation time of the reciprocating compression section (L.COMP) does not pass the set time, it continues with the switching control signal at the initial current peak value. The reciprocating compressor L.COMP is operated, and when the set time elapses, the current peak value of TDC = 0 is detected again and the reciprocating compressor L.COMP is always operated under the condition of TDC = 0. .

In other words, the present invention operates the reciprocating compressor with the switching control signal at the point where TDC, which is the optimum operating condition of the reciprocating compressor, is '0', and then passes a predetermined time to redetect the point where TDC = 0. Then, the current peak value of TDC = 0 is found again, and the refrigerator is operated in an optimal state by operating the reciprocating compressor with the switching control signal at the current peak value.

As described in detail above, when the reciprocating compressor is operated in a refrigerator, the present invention detects peak values of current waveforms and detects switching control signals at the current peak values in order to detect nonlinear characteristics due to mechanical characteristics. While operating the reciprocating compressor, after a certain time, the refrigerator searches for a point where TDC = 0 again and operates the reciprocating compressor of the refrigerator, thereby operating the refrigerator at an optimum state.

Claims (2)

In a refrigerator employing a reciprocating compressor in which the piston changes the stroke in vertical motion by an applied voltage according to the stroke command value, thereby adjusting the cooling power. A first step of detecting an initial current peak value of TDC = 0 by comparing a current applied to the motor with a previously detected current; A second step of setting a time for redetecting an optimal operating condition of TDC = 0 based on the initial current peak detection time of the first step to a predetermined value; A second step of determining whether a predetermined time has elapsed while operating the reciprocating compression unit by controlling the on / off of the triac with the switching control signal corresponding to the current peak value of the first step; As a result of the determination of the second step, if a predetermined time has elapsed, a fourth peak of detecting the current peak value of TDC = 0 again and controlling the operation of the reciprocating compression unit with the switching control signal at the current peak value is performed. Operation control method of a refrigerator using a compressor. The reciprocating compressor according to claim 1, further comprising: controlling operation of the reciprocating compression unit with a switching control signal corresponding to the initial current peak value if a predetermined time has not elapsed based on the initial current peak detection time. Operation control method of the refrigerator using.