KR20020079181A - Driving control method of refrigerator using reciprocating compressor - Google Patents

Abstract

PURPOSE: A method for controlling operation of refrigerator using reciprocating compressor is provided to save power for the refrigerator to work. CONSTITUTION: A method comprises the steps of: a first step comparing current impressed to a motor(M) with previously detected current to detect current peak value where top dead center(TDC) is 0; a second step determining duty ratio of switching control signal by varying the duty ratio until the current peak value detected in the first step decreases by fixed value; a third step measuring integral value of current of switching control signal with duty ratio determined in the second step; and a fourth step controlling operation of a refrigerator by turning on/off a triac(Tr1) with the switching control signal having the duty ratio determined in the second step and varying duty ratio of the switching control signal to keep the integral value of current measured in the third step when load changes.

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, and in particular, a refrigerator using a reciprocating compressor that enables a power saving operation of the refrigerator by varying the capacity of the compressor using current information generated from the reciprocating compressor. It relates to the operation control method of the.

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 to solve the above problems, the operation control of the refrigerator using the reciprocating compressor to enable the power saving operation of the refrigerator by varying the capacity of the compressor using the current information generated in the reciprocating compressor The purpose is to provide a method.

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.

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 a current peak value at which TDC = 0 compared to the current detected at? A second step of varying the duty ratio of the switching control signal until the current peak value detected in the first step is reduced by a predetermined value; A third step of measuring an integral value of the switching control signal having the duty ratio determined in the second step; While controlling the operation of the refrigerator by turning on / off the triac with the switching control signal having the duty ratio determined in the second step, when the load change occurs, the switching control signal is maintained to maintain the current integral value measured in the third step. And performing a fourth step of varying the duty ratio.

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 a current peak value of TDC = 0 compared to the current detected at and detecting the duty ratio of the switching control signal corresponding to the current peak value; A second step of reducing the duty ratio of the switching control signal detected in the first step by a predetermined value and measuring a current integral value in the switching control signal of the reduced duty ratio; When the duty ratio is reduced by a predetermined value, the triac is turned on and off to control the operation of the refrigerator in a power saving mode, and when a load change occurs, the switching control signal to maintain the current integrated value measured in the second step. Characterized in that the third step of varying the duty ratio of the control.

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 a current peak value of TDC = 0 compared to the current detected at and detecting a current integral value in the switching control signal having a duty ratio corresponding to the current peak value; A second step of varying the duty ratio of the switching control signal until the current integral value detected in the first step is reduced by a predetermined value; In a third step of controlling the operation of the refrigerator in the power saving mode by turning on / off the triac with the switching control signal having the duty ratio determined in the second step.

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) which outputs 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 (10 0); 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), the piston is moved up and down by the stroke voltage according to the stroke command value set by the user, thereby the stroke is variable to adjust the cooling force.

That is, when the stroke of the triac Tr1 of the electric circuit unit 10 increases due to the longer turn-on period by 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 a 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, and it can be seen from the experiment that the section where the peak value of the current waveform occurs is the point where the TDC is '0'.

Here, the present invention uses the current peak value detected by the current peak detection unit 100 of the reciprocating compressor to efficiently operate the refrigerator.

That is, the duty peak of the switching control signal is varied until the current peak value of TDC = 0 is detected and the current peak value is reduced by a predetermined value. Then, the switching control signal turns on / off the triac Tr1. While operating the reciprocating compression unit (L.COMP).

Herein, when the reciprocating compression unit L.COMP is continuously operated with a switching control signal that generates a value reduced by a predetermined value from the current peak value, a load variation occurs. In this case, the variable duty ratio After detecting the integral value in the switching control signal having a controllable voltage ratio of the switching control signal by controlling the duty ratio of the switching control signal to maintain the current integral value.

According to another aspect of the present invention, after the switching control signal is detected at a point where TDC = 0, the duty ratio of the switching control signal is reduced to a predetermined value, thereby switching the reduced duty ratio. The reciprocating compressor L.COMP is operated as a control signal, and the integral value of the switching control signal of the reduced duty ratio is measured.

Here, if the reciprocating compression unit (L.COMP) continues to operate with the switching control signal of which the duty ratio is reduced, a change in load occurs. In this case, the switching control signal is maintained so that the measured current integral value is maintained. The duty ratio is controlled to control the voltage applied to the reciprocating compressor L.COMP.

In another aspect of the present invention, the duty of the switching control signal is reduced until the current integrated value is reduced by a predetermined value after finding a point where TDC = 0 and finding the current integrated value at that time. After varying the ratio, the current integral value in the variable switching control signal is measured.

Here, if the reciprocating compressor L.COMP is continuously operated with a switching control signal having a varying duty ratio, a change in load occurs. In this case, the duty ratio of the switching control signal is maintained to maintain the measured current integral value. Is controlled to control the voltage applied to the reciprocating compressor L.COMP.

In other words, the present invention provides a switching control signal having a current peak value at a point where TDC is '0', which is an optimum operating condition of a reciprocating compressor, or a duty ratio at a point where TDC is '0', or TDC is '0'. After obtaining the integral value at the point, in order to increase the operating efficiency of the refrigerator, a switching control signal having a duty ratio which is reduced by a constant value from the current peak value, the switching control signal, and the integral value, respectively. During operation control of the reciprocating compressor, when the load change occurs, the duty ratio of the switching control signal is varied so as to maintain the current integral value in the switching control signal having the reduced duty ratio measured in advance.

As described in detail above, when the reciprocating compressor is operated in a refrigerator, the present invention detects the peak value of the current waveform and detects the peak value of the current waveform in order to detect nonlinear characteristics due to mechanical characteristics. After varying the duty ratio of the switching control signal so as to decrease by, the current integral value in the variable switching control signal is measured, and if the load variation occurs, the duty ratio of the switching control signal is changed to maintain the integral value. Therefore, by controlling the stroke of the reciprocating compressor, it is possible to control the TCD of the piston in consideration of the error due to the nonlinear characteristics, thereby improving the operating efficiency of the refrigerator to which the reciprocating compressor having a variable capacity is applied.

Claims (4)

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 a current peak value of TDC = 0 by comparing a current applied to the motor with a previously detected current; A second step of varying the duty ratio of the switching control signal until the current peak value detected in the first step is reduced by a predetermined value; A third step of measuring an integral value of the switching control signal having the duty ratio determined in the second step; While controlling the operation of the refrigerator by turning on / off the triac with the switching control signal having the duty ratio determined in the second step, when the load change occurs, the switching control signal is maintained to maintain the current integral value measured in the third step. And controlling the duty ratio in a fourth step of controlling the duty ratio. 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 a current peak value of TDC = 0 by comparing a current applied to the motor with a current detected before, and detecting a duty ratio of a switching control signal corresponding to the current peak value; A second step of reducing the duty ratio of the switching control signal detected in the first step by a predetermined value and measuring a current integral value in the switching control signal of the reduced duty ratio; When the duty ratio is reduced by a predetermined value, the triac is turned on and off to control the operation of the refrigerator in a power saving mode, and when a load change occurs, the switching control signal to maintain the current integrated value measured in the second step. The control method of the refrigerator using a reciprocating compressor, characterized in that the third step of controlling the duty ratio of the variable. 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 a current peak value of TDC = 0 by comparing the current applied to the motor with a previously detected current, and detecting a current integral value in the switching control signal having a duty ratio corresponding to the current peak value; ; A second step of varying the duty ratio of the switching control signal until the current integral value detected in the first step is reduced by a predetermined value; And a third step of controlling the operation of the refrigerator in a power saving mode by turning on / off the triac with the switching control signal having the duty ratio determined in the second step. 4. The method of claim 3, further comprising: detecting a current integral value with the switching control signal having the determined duty ratio, and then variably controlling the duty ratio of the switching control signal to maintain the current integral value when a load change occurs. Operation control method of the refrigerator using a reciprocating compressor, characterized in that.