KR20120006878A - Apparatus for controlling linear compressor and method of the same - Google Patents

Abstract

PURPOSE: An apparatus and a method for controlling a linear compressor are provided to improve control accuracy and prevent a fluctuating noise resulting from a beat phenomenon by applying a regular driving voltage. CONSTITUTION: An apparatus for controlling a linear compressor comprises a converter(200), a smoothing capacitor(300), an inverter(400), and a control unit(600). The converter converts DC voltage to AC voltage of commercial electricity. The smoothing capacitor smoothes DC voltage and outputs a direct link voltage. The inverter converts the direct link voltage to a motor driving voltage for a compressor motor according to a control signal. The control unit creates a voltage command value on the basis of the direct link voltage and generates a control signal depending on the voltage command value. The control unit produces a compensation voltage using the motor driving voltage and compensates the voltage command value with the compensation voltage in order to reduce the fluctuation of the motor driving voltage.

Description

Control device and control method of linear compressor {APPARATUS FOR CONTROLLING LINEAR COMPRESSOR AND METHOD OF THE SAME}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear compressor, and more particularly, to a control apparatus and a control method of a linear compressor for reducing a pulsation phenomenon between a frequency of a commercial power supply and a driving frequency of the compressor.

Generally, a compressor is a device that converts mechanical energy into compressed energy of a compressive fluid and is used as part of a refrigeration system, such as a refrigerator or an air conditioner.

The compressor is largely provided with a reciprocating compressor (Reciprocating Compressor) for compressing the refrigerant while the piston reciprocating linearly inside the cylinder to form a compression space between the piston (Piston) and the cylinder (Cylinder) is intake or discharge A rotary compressor and an orbiting scroll for compressing the refrigerant while the roller is eccentrically rotated along the inner wall of the cylinder to form a compression space in which the working gas is sucked or discharged between the eccentrically rotating roller and the cylinder. A scroll compressor is formed between the scroll and the fixed scroll to form a compressed space through which the working gas is sucked or discharged so that the scroll scroll rotates along the fixed scroll to compress the refrigerant.

The reciprocating compressor sucks, compresses and discharges refrigerant gas by linearly reciprocating the inner piston inside the cylinder. The reciprocating compressor is classified into a Recipro method and a Linear method according to a method of driving a piston.

The recipe is a method of coupling a crankshaft to a rotating motor and coupling a piston to the crankshaft to convert the rotational motion of the motor into a linear reciprocating motion. On the other hand, the linear method is a method of reciprocating the piston by the linear motion of the motor by connecting the piston to the mover of the linear motor.

Such a reciprocating compressor is composed of an electric unit generating a driving force, and a compression unit receiving the driving force from the electric unit to compress the fluid. As the electric unit, a motor is generally used a lot, and in the case of the linear method, a linear motor is used.

The linear motor does not require a mechanical conversion device because the motor itself directly generates a linear driving force, and the structure is not complicated. In addition, the linear motor has a characteristic of reducing the loss due to energy conversion and greatly reducing noise because there is no connection site where friction and wear occur. When the linear reciprocating compressor, hereinafter referred to as a linear compressor, is used in a refrigerator or an air conditioner, the compression ratio is changed by changing the stroke voltage applied to the linear compressor. It can be used for variable control of freezing capacity.

On the other hand, the reciprocating compressor, especially the linear compressor, reciprocates in a state in which the piston is not mechanically constrained in the cylinder, so that the piston hits the cylinder wall or the load is suddenly excessively loaded. The piston may not move forward and compression may not be performed properly. Therefore, a control device for controlling the movement of the piston with respect to the load variation or the voltage variation is essential.

In the control apparatus of the linear compressor, the DC link voltage across the smoothing capacitor which stabilizes the rectified voltage is shaken according to the frequency and magnitude of the current consumed at the load side. Therefore, in general, the control device of the linear compressor compensates for the shaking of the DC link voltage by measuring the DC link voltage and adjusting the duty of the pulse width modulated pulse of the inverter, wherein the DC link voltage measurement point and the pulse width modulated pulse drive are performed. There is a problem in that accurate compensation is not performed due to a phase delay between the time points, that is, the time of outputting the motor driving voltage. In addition, the control apparatus of the linear compressor according to the prior art, when the power source frequency and the compressor driving frequency is similar, the motor driving voltage is changed slowly due to the frequency (beating frequency) corresponding to the difference between the two frequencies of the compressor There is a problem that causes shaking in stroke size and input. Accordingly, the control apparatus of the linear compressor according to the prior art has a problem of poor control reliability.

An object of the present invention is to provide a control apparatus and a control method of a linear compressor for reducing the phenomena caused by the difference between the frequency of the commercial power source and the drive frequency of the compressor.

The present invention compensates the voltage setpoint of the current cycle by using the motor drive voltage of the previous cycle, thereby reducing the pulsation caused by the phase delay caused by the difference between the time of the DC link voltage measurement and the output of the voltage setpoint. Another object of the present invention is to provide a control apparatus and a control method of a linear compressor that suppresses a shaking phenomenon.

The control apparatus of the linear compressor according to the present invention for achieving the above objects, the converter for converting the AC voltage of the commercial power supply to a direct current voltage, a smoothing capacitor for outputting a direct current link voltage by smoothing the direct voltage, and a control signal The inverter converts and outputs the DC link voltage into a motor driving voltage of a compressor motor, and generates a voltage command value based on the DC link voltage and generates the control signal according to the voltage command value. The control unit calculates a compensation voltage using the motor driving voltage, compensates the voltage command value based on the compensation voltage, and reduces the tremor of the motor driving voltage.

The control apparatus of the linear compressor according to the present invention further includes a driving voltage detecting unit for detecting the motor driving voltage every predetermined time period, wherein the control unit uses the motor driving voltage detected in a previous period to compensate the compensation voltage. Calculate

In addition, the control unit compares the value accumulated in one period with the value accumulated in one period and the motor driving voltage in one period, and compensates the voltage command value in the next period based on the error of the accumulated values. do.

In the control apparatus of the linear compressor according to the present invention, the control unit includes: a first integration module for integrating the voltage command value for one period and outputting a first integration value; And a compensation voltage calculation module for calculating the compensation voltage using the first integration value and the second integration value. The control unit further includes a comparison module for comparing the first integrated value with the second integrated value and outputting an error thereof.

The control apparatus of the linear compressor according to the present invention for achieving the above objects, the converter for converting the AC voltage of the commercial power supply to a direct current voltage, a smoothing capacitor for outputting a direct current link voltage by smoothing the direct voltage, and a control signal According to the present invention, the inverter converts the DC link voltage into a motor driving voltage of a compressor motor, and outputs the first voltage detection unit to detect the DC link voltage at a predetermined time period. Generating a voltage command value based on a second voltage detection unit and the DC link voltage, calculating a compensation voltage based on the motor driving voltage, and compensating the voltage command value based on the compensated voltage command value; It is configured to include a control unit that occurs.

In the control apparatus of the linear compressor according to the present invention, the control unit calculates the compensation voltage using the motor driving voltage detected in the previous period.

The control apparatus of the linear compressor according to the present invention includes: a first integration unit for integrating the voltage command value and outputting a first integration value; a second integration unit for integrating the motor driving voltage and outputting a second integration value; And a compensating unit for comparing the first integrated value with the second integrated value and outputting the error, and the compensating voltage calculating unit calculating the compensation voltage based on the error. Moreover, the control apparatus of the linear compressor which concerns on this invention is comprised further including the storage unit which stores the said 1st integrated value and the said 2nd integrated value.

The control method of the linear compressor according to the present invention for achieving the above objects, to calculate the compensation voltage using the motor drive voltage applied to the compressor motor in the previous time period, and to drive the compressor using the compensation voltage Compensating the voltage command value, and driving the compressor with the compensated voltage command value to reduce the tremor of the motor drive voltage.

The control method of the linear compressor according to the present invention includes detecting the DC link voltage at a predetermined time period, generating a voltage command value based on the DC link voltage, and generating the DC link voltage according to a control signal. Converting and outputting a motor driving voltage of a compressor motor; detecting the motor driving voltage according to the time period; calculating a compensation voltage based on the motor driving voltage; and based on the compensation voltage. Compensating the voltage setpoint and generating the control signal based on the compensated voltage setpoint.

The control method of the linear compressor according to the present invention includes the steps of: integrating the voltage command value, integrating the motor driving voltage, calculating an integrated value of the voltage command value, and an error of the integration value of the motor driving voltage. The method may further include calculating the compensation voltage based on the error. The control method of the linear compressor according to the present invention further includes the step of storing the integrated value of the voltage command value and the integrated value of the motor driving voltage.

The control apparatus and control method of the linear compressor according to the present invention suppress the phenomenon that the motor drive voltage is shaken due to the beat frequency generated by the difference between the frequency of the commercial power source and the drive frequency of the compressor.

The present invention improves control accuracy by applying a constant drive voltage to the compressor, suppresses generation of fluctuating noise due to a beat phenomenon, and improves system stability.

1 is a block diagram schematically showing a configuration of a control apparatus of a linear compressor according to an embodiment of the present invention;
FIG. 2 is a block diagram showing the detailed configuration of a control unit in FIG. 1; FIG.
3 is a graph for explaining occurrence of shaking and beat phenomenon of the DC link voltage;
4 is a graph showing the direct current link voltage and current in a smoothing capacitor;
FIG. 5 is a graph for explaining an operation of measuring a DC link voltage according to the present invention in FIG. 4; FIG.
6 is a circuit diagram for explaining the variation of the DC link voltage;
7 is a view for explaining the compensation operation of the motor drive voltage according to the present invention;
8 is a block diagram schematically showing a configuration of a control apparatus of a linear compressor according to another example of the present invention;
9 and 10 are flowcharts schematically illustrating a control method of the linear compressor according to the present invention.

Hereinafter, a control apparatus and a control method of a linear compressor according to the present invention will be described in detail with reference to the accompanying drawings.

1 and 2 together, the control apparatus of the linear compressor according to the present invention, the converter 200 for converting the AC voltage of the commercial power supply 100 to a DC voltage, and the DC link voltage by smoothing the DC voltage A smoothing capacitor 300 for outputting the voltage, an inverter 400 for converting the DC link voltage into a motor driving voltage of the compressor motor 500 according to a control signal, and a voltage command value based on the DC link voltage. And a control unit 600 for generating the control signal according to the voltage command value, wherein the control unit 600 calculates a compensation voltage using the motor driving voltage, based on the compensation voltage. Compensating the voltage command value reduces the tremor of the motor drive voltage. The tremor of the motor driving voltage is caused by the beat frequency between the frequency of the commercial power supply and the driving frequency of the compressor, which increases as the two frequencies get closer. In this case, the control signal is generally a PWM signal for controlling the pulse width modulation (PWM) voltage duty of the inverter 400. The inverter 400 supplies the input voltage, that is, the motor driving voltage, to the compressor motor 500 according to the control signal.

The control apparatus of the linear compressor further includes a driving voltage detection unit 700 for detecting the motor driving voltage at a predetermined time period, and the control unit 600 uses the motor driving voltage detected in a previous cycle. To calculate the compensation voltage.

In addition, the control unit 600 compares the value obtained by integrating the voltage command value for one period with the value in which the motor driving voltage is integrated in one period, and based on the error of the accumulated values, the voltage of the next period. Compensate for the setpoint.

The control unit 600 includes a first integration module 610 for integrating the voltage command value for one period and outputting a first integration value, and a second for integrating the motor driving voltage for one period and outputting a second integration value. An integration module 620 and a compensation voltage calculation module 640 for calculating the compensation voltage using the first and second integration values are further included. The control unit 600 further includes a comparison module 630 which compares the first integrated value with the second integrated value and outputs an error thereof.

3, A is a DC link voltage, B is an inverter output voltage, i.e., a motor drive voltage, C is a pulse width modulation command voltage, i.e., a voltage command value, D is a motor drive root mean square (RMS) voltage, and E is a voltage command. RMS value is indicated. Referring to FIG. 3, it can be seen that there is a difference between the voltage command value and the actual motor driving voltage according to the change of the DC link voltage. This causes a vibration phenomenon during stroke control of the linear compressor. This phenomenon is called a beat phenomenon, which occurs as the difference between the frequency of the commercial power supply and the motor driving frequency decreases.

Referring to FIG. 4, it can be seen that the DC link voltage in the smoothing capacitor 300 and the current flowing in the smoothing capacitor 300 are shaken with time. In general, when the commercial power supply 100 is AC 220V, the DC voltage stored in the smoothing capacitor 300 is about 311V, but in reality there is a trembling as shown in FIG.

Referring to FIG. 6, it can be seen that the amount of current flowing in the smoothing capacitor ic is changed by the current il flowing to the stage or the load of the compressor motor. That is, it is expressed as Equation 1 below.

Where Vdc is a DC link voltage, C is capacitance, ic is current flowing in the smoothing capacitor, and il is current flowing to the compressor.

In view of the above, as shown in FIG. 5, it can be seen that the DC link voltage varies depending on the timing of measuring the DC link voltage. Accordingly, precise control is not performed at the time of stroke control of the compressor, resulting in stroke shaking.

When the interrupt signal for calculating the pulse width modulation is generated, the control unit 600 sets the duty of the pulse width modulation pulse according to the voltage command value, calculates the compensation value based on the DC link voltage measured in advance, and outputs the calculated value. do. In this case, since the time point for calculating the duty of the pulse width modulation is different from the time point at which the pulse width modulation signal is actually output, that is, the time point for measuring the DC link voltage and the time point for outputting the motor driving voltage are different. 2 The integration module 620 calculates the average voltage of the pulse width modulation duty calculated in the previous period in consideration of the phase delay and the pulse width modulation pulse actually output at the time when the pulse width modulation pulse is output, that is, the motor driving voltage. Calculate and integrate. The first integration module 610 calculates and integrates a pulse width modulation duty command value, that is, a voltage command value that does not compensate the DC link voltage. The comparison module 630 compares the voltage command value output from the first integration module 610 with the motor driving voltage output from the second integration module 620, and outputs a difference (error). The compensation voltage calculation module 640 multiplies the error by 1.4 times, and then corrects it when calculating the next periodic voltage command value.

Ideally, a 311V DC link voltage should be applied to the compressor via the inverter 400 at a duty determined according to the voltage command value. However, the linear compressor actually shakes with the DC link voltage. In order to apply a constant voltage and current to the compressor, the control apparatus of the linear compressor according to the present invention applies power compensated to the actual DC link voltage as shown in FIG. 7 to supply power to the compressor. .

Referring to FIG. 8, a control apparatus of a linear compressor according to another example of the present invention includes a converter 200 for converting an AC voltage of a commercial power supply 100 into a DC voltage, and smoothing the DC voltage to generate a DC link voltage. A smoothing capacitor 300 for outputting, an inverter 400 for converting the DC link voltage to a motor driving voltage of a compressor motor according to a control signal, and a first voltage detection for detecting the DC link voltage at a predetermined time period A unit 710, a second voltage detection unit 720 for detecting the motor driving voltage according to the time period, and a voltage command value based on the DC link voltage, and generating a compensation voltage based on the motor driving voltage. The control unit 600 is configured to compensate for the voltage command value and generate the control signal based on the compensated voltage command value. In this case, the control signal is generally a PWM signal for controlling the pulse width modulation (PWM) voltage duty of the inverter 400. The inverter 400 supplies the input voltage, that is, the motor driving voltage, to the compressor motor 500 according to the control signal.

Here, the control unit 600 calculates the compensation voltage using the motor driving voltage detected in the previous period.

The control apparatus of the linear compressor includes: a first integration unit 910 for integrating the voltage command value and outputting a first integration value; a second integration unit 920 for integrating the motor driving voltage and outputting a second integration value; And a comparison unit 930 for comparing the first integrated value with the second integrated value and outputting an error thereof, and a compensation voltage calculating unit 940 for calculating the compensation voltage based on the error. do.

The second integration unit 920 has a point in time at which the duty of calculating the pulse width modulation is different from a point in time at which the pulse width modulation signal is actually output. That is, the measurement point of the DC link voltage and the motor driving voltage are output. Since the time points are different from each other, the pulse width modulation duty calculated in the previous period and the average voltage of the pulse width modulation pulses actually output at the time when the pulse width modulation pulses are output in consideration of the phase delay are calculated. Accumulate. In addition, the first integration unit 910 calculates and integrates a pulse width modulation duty command value, that is, a voltage command value, which does not compensate the DC link voltage. The comparison unit 930 compares the voltage command value output from the first integration unit 910 with the motor driving voltage output from the second integration unit 920, and outputs a difference (error). The compensation voltage calculating unit 940 outputs a compensation voltage multiplied by 1.4 times the error. The control unit 600 corrects when calculating the next periodic voltage command value. That is, when the interrupt signal for calculating pulse width modulation is generated, the control unit 600 sets the duty of the pulse width modulation pulse according to the voltage command value, and calculates the compensation voltage based on the DC link voltage measured in advance. The compensation value calculated through the unit 940 is compensated for and output to the voltage command value.

The control apparatus of the linear compressor further includes a storage unit 800 that stores the first integrated value and the second integrated value. The storage unit 800 may use a random access memory (RAM), a flash memory, or the like.

In Fig. 3, A is a DC link voltage, B is an inverter output voltage, i.e., a motor drive voltage, C is a pulse width modulation command voltage, i.e., a voltage command value, D is a motor drive rms voltage, and E is a voltage command rms value. Referring to FIG. 3, it can be seen that there is a difference between the voltage command value and the actual motor driving voltage according to the change of the DC link voltage. This causes a vibration phenomenon during stroke control of the linear compressor. This phenomenon is called a beat phenomenon, which occurs as the difference between the frequency of the commercial power supply and the motor driving frequency decreases.

Referring to FIG. 4, it can be seen that the DC link voltage in the smoothing capacitor 300 and the current flowing in the smoothing capacitor 300 are shaken with time. In general, when the commercial power supply 100 is AC 220V, the DC voltage stored in the smoothing capacitor 300 is about 311V, but in reality there is a trembling as shown in FIG.

Referring to FIG. 6, it can be seen that the amount of current flowing in the smoothing capacitor ic is changed by the current il flowing to the stage or the load of the compressor motor. That is, the current flowing through the linear compressor generates a current drop by the load current il.

Referring to FIG. 5, it can be seen that the DC link voltage varies according to the timing of measuring the DC link voltage. Accordingly, precise control is not performed at the time of stroke control of the compressor, resulting in stroke shaking.

9 and 10, in the control method of the linear compressor according to the present invention, a compensation voltage is calculated using a motor driving voltage applied to a compressor motor in a previous time period, and the compressor is operated using the compensation voltage. Compensating the voltage command value for driving, and driving the compressor with the compensated voltage command value to reduce the tremor of the motor drive voltage.

9, the control method of the linear compressor according to the present invention includes detecting the DC link voltage at a predetermined time period (S100) and generating a voltage command value based on the DC link voltage (S200). And converting the DC link voltage into a motor driving voltage of the compressor motor according to a control signal (S400), detecting the motor driving voltage according to the time period (S600), and driving the motor. Calculating a compensation voltage based on a voltage (S700), compensating the voltage command value based on the compensation voltage (S800), and generating the control signal based on the compensated voltage command value (S300). It is configured to include.

Referring to FIG. 10, the control method of the linear compressor includes: integrating the voltage command value (S610), integrating the motor driving voltage (S620), integrated value of the voltage command value, and driving the motor. Comprising a step (S630) for calculating the error of the integrated value of the voltage. In this case, in the calculating of the compensation voltage (S700), the compensation voltage is calculated based on the error. Hereinafter, the configuration of the apparatus will be described with reference to FIGS. 1 to 8.

In the control apparatus of the linear compressor for converting the AC voltage of the commercial power supply to a DC voltage, smoothing and storing the DC voltage, and converts the DC voltage stored corresponding to the load of the linear compressor into a motor driving voltage to drive the linear compressor. In operation S100, the control device detects a smooth and stored DC link voltage at each predetermined time period. The control device is the DC link voltage

The control device calculates and integrates a pulse width modulation duty command value, that is, a voltage command value, which does not compensate the DC link voltage (S610). Further, the control device calculates the average voltage of the pulse width modulated pulse actually output, that is, the motor driving voltage, with the pulse width modulated duty calculated in the previous period and the DC link voltage measured at the time when the pulse width modulated pulse is output. The integration is performed (S620). That is, the control device is different from the time point at which the pulse width modulation signal is calculated and the time point at which the pulse width modulation signal is actually output, that is, the time point at which the DC link voltage is measured and the time point at which the motor driving voltage is output are different. Since it is different, the phase delay is taken into consideration. Then, the control device compares the integrated voltage command value with the integrated motor driving voltage, calculates a difference (error) (S630), and calculates a compensation voltage multiplied by 1.4 times the error (S700). . The control device corrects the next periodic voltage command value using the compensation voltage (S800). That is, when the interrupt signal for calculating the pulse width modulation occurs, the control device sets the duty of the pulse width modulation pulse according to the voltage command value, calculates the compensation voltage based on the measured DC link voltage in advance, and then The control signal is generated by compensating for the voltage command value of the period (S300).

The control method of the linear compressor further includes storing an integrated value of the voltage command value and an integrated value of the motor driving voltage (not shown).

In the linear compressor, the error of the pulse width modulated pulse generated due to the phase delay becomes maximum near the maximum pulse width modulated duty in the case of sinusoidal output, and the voltage output error corresponding to one period also becomes maximum. When the beat phenomenon severely affects the control quality, the difference between the supply frequency and the compressor driving frequency is small, and there is little difference in the voltage output error between the previous cycle and the current cycle. As described above, the control apparatus and control method of the linear compressor according to the present invention actually calculate the motor drive voltage output in the previous cycle in order to take into account the phase delay the pulse width modulation duty value and the DC link voltage measurement of the previous cycle. The voltage command value of the current period is corrected based on this value so that uniform power can be transmitted to the compressor.

100: commercial power 200: converter;
300: smoothing capacitor 400: inverter
500: compressor motor 600: control unit
700: drive voltage detection unit 800: storage unit
610: first integration module 620: second integration module
630: comparison module 640: compensation voltage calculation module
710: first voltage detection unit 720: second voltage detection unit
910: first integration unit 920: second integration unit
930: comparison unit 940: compensation voltage calculation unit

Claims (13)

A converter for converting an AC voltage of a commercial power source into a DC voltage;
A smoothing capacitor that outputs a DC link voltage by smoothing the DC voltage;
An inverter converting the DC link voltage into a motor driving voltage of a compressor motor and outputting the same according to a control signal; And
And a control unit generating a voltage command value based on the DC link voltage and generating the control signal according to the voltage command value.
And the control unit calculates a compensation voltage using the motor driving voltage, and compensates for the voltage command value based on the compensation voltage to reduce vibration of the motor driving voltage. The method according to claim 1,
And a driving voltage detecting unit detecting the motor driving voltage every predetermined time period.
And the control unit calculates the compensation voltage using the motor driving voltage detected in a previous cycle. The method of claim 2,
The control unit compares the value obtained by integrating the voltage command value for one period with the value obtained by integrating the motor driving voltage for one period and compensates the voltage command value of the next period based on the error of the integrated values. A control device for a linear compressor. The method of claim 2, wherein the control unit,
A first integration module for integrating the voltage command value for one period and outputting a first integrated value;
A second integration module which integrates the motor driving voltage for one period to output a second integration value; And
And a compensation voltage calculating module configured to calculate the compensation voltage using the first integrated value and the second integrated value. The method of claim 4, wherein
And a comparison module for comparing the first integrated value with the second integrated value and outputting an error thereof. A converter for converting an AC voltage of a commercial power source into a DC voltage;
A smoothing capacitor that outputs a DC link voltage by smoothing the DC voltage;
An inverter converting the DC link voltage into a motor driving voltage of a compressor motor and outputting the same according to a control signal;
A first voltage detection unit detecting the DC link voltage at a predetermined time period;
A second voltage detection unit detecting the motor driving voltage in accordance with the time period; And
A control unit generating a voltage command value based on the DC link voltage, calculating a compensation voltage based on the motor driving voltage, and compensating the voltage command value and generating the control signal based on the compensated voltage command value. Control device of linear compressor. The method of claim 6,
And the control unit calculates the compensation voltage using the motor driving voltage detected in a previous cycle. The method of claim 6,
A first integration unit for integrating the voltage command value and outputting a first integrated value;
A second integration unit for integrating the motor driving voltage to output a second integration value;
A comparison unit for comparing the first integrated value with the second integrated value and outputting an error thereof; And
And a compensation voltage calculating unit calculating the compensation voltage based on the error. The method of claim 8,
And a storage unit which stores the first integrated value and the second integrated value. Compensation voltage is calculated using the motor driving voltage applied to the compressor motor in the previous time period, and the voltage command value for driving the compressor is compensated using the compensation voltage, and the compressor is driven by the compensated voltage command value. A control method of a linear compressor that reduces the tremor of a motor drive voltage. The method of claim 10,
Detecting the DC link voltage at each time period;
Generating a voltage setpoint based on the DC link voltage;
Converting the DC link voltage into a motor driving voltage of the compressor motor according to a control signal and outputting the converted motor link voltage;
Detecting the motor driving voltage according to the time period;
Calculating a compensation voltage based on the motor driving voltage;
Compensating for the voltage setpoint based on the compensation voltage; And
Generating the control signal based on the compensated voltage command value. The method of claim 11, wherein
Integrating the voltage command value;
Integrating the motor drive voltage;
Calculating an error between the integrated value of the voltage command value and the integrated value of the motor driving voltage;
The calculating of the compensation voltage may include calculating the compensation voltage based on the error. The method of claim 12,
And storing the integrated value of the voltage command value and the integrated value of the motor driving voltage.

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