JP3218027B2 - Operation control method for compressor of inverter refrigerator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling the operation of a compressor of an inverter refrigerator, and more particularly, to controlling the operating frequency of a compressor motor in a lubrication mode to reduce noise and noise when the compressor is driven. The present invention relates to an operation control method for a compressor of an inverter refrigerator that can reduce power consumption.

[0002]

2. Description of the Related Art Generally, in an inverter refrigerator,
Pulse width modulation (hereinafter referred to as P
WM) The inverter which receives the signal and the commercial AC power and converts it to DC power, and controls the DC power output to the compressor motor based on the PWM signal to change the rotation speed of the compressor motor. Then, the cooling rate (or temperature) in the inverter refrigerator is adjusted.

That is, as the number of rotations of the motor of the compressor increases, the cooling rate in the refrigerator increases relatively, and as the number of rotations decreases, the cooling rate in the refrigerator decreases relatively. FIG. 6 is a graph showing an operating frequency characteristic curve of the motor of the compressor according to the load state of the conventional inverter refrigerator configured as described above. In the figure, the state A indicates only the load amount preset in the refrigerator. B indicates the operating frequency of the compressor motor when a load is applied, and state B indicates the operating frequency of the compressor motor when a load greater than a preset load is applied to the refrigerator. The state indicates the operating frequency of the motor of the compressor when a load smaller than a preset load is applied to the refrigerator.

[0004] The microcomputer in the refrigerator compares the detected temperature in the refrigerator with the set temperature for each operating frequency of the compressor motor set by the user, and determines that the load in the refrigerator is in the A state. By rotating the compressor motor at 3600 rpm by a control signal having a frequency (60 Hz) similar to the frequency (60 Hz) of the commercial AC power supply, if the load in the refrigerator is in the B state as a result of the comparison, the commercial AC power supply 4800 rpm by a control signal having a higher frequency (80 Hz) than the frequency (60 Hz)
As a result of the comparison, when the load in the refrigerator is in the C state, the frequency (6
The compressor motor is rotated at 1800 rpm by a control signal having a frequency (30 Hz) lower than 0 Hz.

At this time, in order to normally rotate the motor of the compressor which has been stopped, it is necessary to go through a lubrication mode in which lubricating oil is supplied to each mechanical part constituting the compressor. That is, in such a lubrication mode, when the compressor motor rotates, the compressor motor is rotated for a predetermined time by a control signal having a specific frequency at which lubrication is performed most smoothly, and the compressor cylinder and Since the peripheral parts are lubricated, noise due to the operation of the compressor and wear of the cylinder of the compressor can be reduced.

FIG. 7 is a graph showing an operating frequency characteristic curve for each stage of the compressor motor during the operation of the compressor of the conventional inverter refrigerator. As shown, the motor of the compressor is as follows. Normal rotation is performed after various stages. That is, an initial phase stage (t0) in which a current is supplied to the stator coil to always set the rotor to a constant phase, and a current corresponding to a preset torque is supplied to the stator coil to start the compressor. A step of starting the motor of the compressor while increasing the number of rotations of the motor (t0 to t1), and a transition step (t1 to t2)
After that, when the number of revolutions of the motor increases and induced electromotive force is generated, the position of the rotor is detected based on the current flowing through the stator coil, and the position of the stator is detected in accordance with the detected position of the rotor. A rotor detection operation stage (t2 to t3) for controlling so as to supply a current to the coils of each phase; and supplying lubricating oil for smooth driving to the compressor cylinder and its surroundings, and After a lubrication step (t3 to t4) for allowing the motor to rotate normally, the compressor motor rotates normally.

At this time, in the compressor of the conventional inverter refrigerator, the lubrication step is performed at an operation frequency of 60 Hz.

[0008]

However, in such a conventional method for controlling the operation of a compressor of an inverter refrigerator, all of the operations are performed only at a specific operation frequency of 60 Hz for a predetermined time regardless of the specifications of the refrigerator. Since the motor of the compressor is lubricated, there is an inconvenience that much power is consumed and noise is generated.

[0009] Therefore, an object of the present invention has been made in view of such a conventional problem.
An object of the present invention is to provide an operation control method of a compressor of an inverter refrigerator that can reduce noise and power consumption. Further, another object of the present invention is to set a lubrication mode frequency band of a compressor and vary a frequency within the frequency band to reduce noise and power consumption when driving the compressor. An object of the present invention is to provide an operation control method for a machine.

[0010]

Means for Solving the Problems To achieve such an object
To operate the compressor of the inverter refrigerator according to the present invention.
In the turn control method,When starting the compressor, lubrication mode
Lubrication mode frequency determined by start frequency and stop frequency
Set several bands, lubrication time, and resonance frequency band respectively
And then determine if the lubrication mode start frequency has been reached
The lubrication mode
When the lubrication mode frequency reaches the lubrication mode frequency band,
Operating frequency of the compressor motor within the
After starting lubrication of the compressor at a constant rate of increase,
A second step of determining whether the lubrication time has elapsed;
If the lubrication time elapses as a result of the stage determination, refrigerate
Detects the temperature inside the chamber and operates the compressor motor at that time
3rd stage to set frequency and switch to normal operation mode
Are sequentially performed.

[0011] In the operation control method of the inverter refrigerator compressor according to the present invention, the compressor at startup, Jun
Lubrication mode determined by the slip mode start frequency and stop frequency
Frequency band, lubrication time, and resonance frequency band
After each setting, the lubrication mode start frequency was reached
A first step of judging whether or not
When the lubrication mode start frequency is reached, the lubrication mode
The operating frequency of the compressor motor should be within the frequency band.
Start lubricating the compressor by reducing the wave number at a constant rate.
A second step of determining whether the lubrication time has elapsed after
And the lubrication time has passed as a result of the determination in the second step.
If the temperature in the refrigerator is detected, the
Set the operating frequency when switching to normal operation mode
The third step is performed sequentially.

[0012]

[0013]

[0014]

Embodiments of the present invention will be described below with reference to the drawings. In the first embodiment of the operation control method of the compressor of the inverter refrigerator according to the present invention,
As shown in FIG. 1, when the compressor is started, the lubrication mode frequency band (f2 to f3) (or the lubrication mode start frequency (f
2) and stop frequency (f3)), lubrication time (t3 to t4) and resonance frequency band (f4 to f5) are set (S
After T1), the microcomputer increases the operating frequency (f) of the motor of the compressor to increase the operating frequency (f).
Is determined to be within the lubrication mode frequency band (f2 to f3) (ST2). As a result, if the operation frequency (f) is within the lubrication mode frequency band (f2 to f3), the lubrication time is determined. From (t3 to t4), the operating frequency increase rate a or the angle increase rate a is constantly increased or decreased as shown in FIG. 3 or FIG. 5 from the rotation speed corresponding to the operation frequency (f), The compressor motor is rotated at such a speed that does not deviate from the lubrication mode frequency band (ST3),
Lubrication time (t) for increasing the rotation speed of the motor of the compressor
It is determined whether or not 3 to t4) has elapsed (ST4). If the lubrication time (t3 to t4) has elapsed, the detected temperature in the refrigerator is compared with a preset temperature set for each frequency. (ST
5) If the detected temperature in the refrigerator is higher than the set temperature for each frequency, the motor of the compressor is rotated at a rotation speed corresponding to a frequency higher than the resonance frequency band (f4 to f5), and If not high, the resonance frequency band (f4 to f5)
The compressor motor is rotated at a rotation speed corresponding to a lower frequency (ST6, ST7).

At this time, the lubrication mode frequency band (f
2 to f3) are 38 to 42 Hz, the resonance frequency band (f4 to f5) is 48 to 52 Hz, and the lubrication time (t3 to t4) is about 10 to 20 seconds. FIG. 2 is a flowchart showing a second embodiment of the operation control method of the compressor of the inverter refrigerator according to the present invention, and FIG. 3 is a flowchart showing the operation control method of the compressor of the inverter refrigerator according to the second embodiment of the present invention. 4 is a graph showing an operating frequency characteristic curve of a compressor motor.

In the second embodiment of the operation control method for the compressor of the inverter refrigerator according to the present invention, as shown in FIG. 2, the lubrication mode frequency band (f2 to f
3) and the upper limit frequency of these lubrication mode frequency bands (f3)
And a lower limit frequency (f2), a lubrication time (t3 to t4) and a resonance frequency band (f4 to f5) are set (ST1).
0), it is determined whether or not the lower limit frequency (f2) of the lubrication mode frequency band (f2 to f3) has been reached (ST11).
12).

Next, during the lubrication operation, it is determined whether or not the operating frequency (f) in the lubrication mode has deviated from the lower limit frequency (f2) of the lubrication mode frequency band (f2 to f3) by the voltage ripple (ST13). When the frequency deviates from the frequency (f2), the voltage is increased to increase the frequency to the lower limit frequency (f2) or higher (ST14). If the judgment result indicates that the frequency does not deviate from the lower limit frequency (f2), the lubrication mode frequency band ( It is determined whether the upper limit frequency (f3) of f2 to f3) has been deviated (ST15).

As a result, in the lubrication mode, the operating frequency (f)
If the frequency deviates from the upper limit frequency (f3) of the lubrication mode frequency band, the voltage is reduced to be lower than the upper limit frequency (f3) (ST16). It is determined whether t4) has elapsed (ST17).
. As a result of the determination, if the predetermined lubrication time (t3 to t4) has not elapsed, the lubrication mode frequency band (f2 to f
3) Output a control signal corresponding to the operation frequency (f) to continue the lubrication operation of the motor of the compressor (ST13 to ST16),
When the lubrication time (t3 to t4) has elapsed, the detected temperature in the refrigerator is compared with a preset temperature in the refrigerator (ST18), and the detected temperature in the refrigerator is set in the refrigerator. If the temperature is higher than the temperature, the motor of the compressor is rotated at a rotation speed corresponding to a frequency higher than the resonance frequency band (f4 to f5). The motor of the compressor is rotated at a rotation speed corresponding to a frequency lower than f5) (ST19, ST20).

FIG. 4 is a flow chart showing a third embodiment of the method for controlling the operation of the compressor of the inverter refrigerator according to the present invention, and FIG. 5 is the operation of the compressor of the inverter refrigerator according to the third embodiment of the present invention. 4 is a graph showing an operating frequency characteristic curve of a motor of a compressor in a control method. In the third embodiment of the operation control method for the compressor of the inverter refrigerator according to the present invention, as shown in FIG. 4, the lubrication mode frequency band (f2 to f3) at the time of initial startup and the upper limit of the lubrication mode frequency band. Frequency (f3) and lower limit frequency (f2)
And the lubrication time (t3 to t4) and the resonance frequency band (f4 to
f5) and (ST30), it is determined whether or not the upper limit frequency (f3) of the lubrication mode frequency band (f2 to f3) has been reached (ST31). Is performed (ST32).

Next, it is determined whether or not the operating frequency (f) has deviated from the upper limit frequency (f3) of the lubrication mode frequency band in the lubrication mode due to the voltage ripple during the lubrication operation (ST33).
Then, when the frequency deviates from the upper limit frequency (f3), the voltage is reduced to lower the voltage to the upper limit frequency (f3) or lower (ST34).
If it is determined that the frequency does not deviate from the upper limit frequency (f3), it is determined whether the frequency deviates from the lower limit frequency (f2) of the lubrication mode frequency band (ST35).

As a result, the operating frequency (f) in the lubrication mode
If the frequency deviates from the lower limit frequency (f2) of the lubrication mode frequency band (f2 to f3), the voltage is increased to increase to or higher than the lower limit frequency (f2) (ST36). It is determined whether the lubrication time (t3 to t4) has elapsed (ST37). As a result of the judgment, the predetermined lubrication time (t3 to
If t4) has not elapsed, a control signal corresponding to the operating frequency (f) of the lubrication mode frequency band (f2 to f3) is output to continue the lubrication operation of the compressor motor (ST33).
To ST36), the lubrication time (t3 to t4) elapses (S3).
T37) and the detected refrigerator temperature inside the refrigerator and a preset frequency-specific set temperature (ST38). If the refrigerator internal temperature is higher than the frequency-specific set temperature, the resonance frequency band (T37) is compared. The motor of the compressor is rotated at a rotation speed corresponding to a frequency higher than f4 to f5). The compressor motor is rotated (ST39 to ST40).

[0022]

As described above, in the operation control method of the compressor of the inverter refrigerator according to the present invention, 60
For a predetermined lubrication time in a frequency band lower than 30 Hz (38 Hz to 42 Hz), the frequency in the frequency band is varied to lubricate the compressor and reduce noise and power consumption when the compressor is driven. There is.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a first embodiment of an operation control method for a compressor of an inverter refrigerator according to the present invention.

FIG. 2 is a flowchart showing a second embodiment of the operation control method of the compressor of the inverter refrigerator according to the present invention.

FIG. 3 is a graph showing an operating frequency characteristic curve of a compressor motor in an operation control method for a compressor of an inverter refrigerator according to a second embodiment of the present invention.

FIG. 4 is a flowchart showing a third embodiment of the operation control method of the compressor of the inverter refrigerator according to the present invention.

FIG. 5 is a graph showing an operating frequency characteristic curve of a motor of a compressor in an operation control method for a compressor of an inverter refrigerator according to a third embodiment of the present invention.

FIG. 6 is a graph showing a characteristic curve of an operating frequency of a compressor motor according to a load state of a conventional inverter refrigerator.

FIG. 7 is a graph showing an operating frequency characteristic curve of a motor of a compressor according to a conventional compressor operating stage of an inverter refrigerator.

Continuation of the front page (56) References JP-A-7-257163 (JP, A) JP-A-5-322410 (JP, A) JP-A-63-21445 (JP, A) JP-A-4-281159 (JP) , A) Japanese Utility Model Hei 1-125970 (JP, U) Japanese Utility Model Utility Model 2-49400 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F25D 11/00 101 F04B 49/06 341

Claims (5)

(57) [Claims] 1. A lubrication mode starting frequency when a compressor is started.
Lubrication mode frequency band determined by number and stop frequency,
After setting the lubrication time and the resonance frequency band respectively,
First to determine whether the lubrication mode start frequency has been reached
And the lubrication mode start frequency
When it reaches, the range that does not deviate from the lubrication mode frequency band
Increases the operating frequency of the compressor motor at a constant rate.
After starting the compressor lubrication, the lubrication time elapses
A second step of determining whether the lubrication time has elapsed as a result of the determination in the second step
Detects the temperature inside the refrigerator,
To set normal operation mode and change to normal operation mode
And a step of sequentially performing the steps , the operation control method of the compressor of the inverter refrigerator. 2. A lubrication mode start frequency when the compressor is started.
Lubrication mode frequency band determined by number and stop frequency,
After setting the lubrication time and the resonance frequency band respectively,
First to determine whether the lubrication mode start frequency has been reached
And the lubrication mode start frequency
When it reaches, the range that does not deviate from the lubrication mode frequency band
And the operating frequency of the compressor motor is reduced at a constant rate.
After starting the compressor lubrication, the lubrication time elapses
A second step of determining whether the lubrication time has elapsed as a result of the determination in the second step
Detects the temperature inside the refrigerator,
To set normal operation mode and change to normal operation mode
And a step of sequentially performing the steps, the operation control method of the compressor of the inverter refrigerator. Wherein the lubricating mode frequency band, the operation control method of the inverter refrigerator compressor according to claim 1 or 2, characterized in that the a frequency band lower than the resonance frequency band. 4. The lubrication mode frequency band is 38-4.
4. The method according to claim 1, wherein the frequency is set to 2 Hz.
An operation control method for a compressor of an inverter refrigerator according to any one of the preceding claims. Wherein said resonant frequency band, the operation control method of the inverter refrigerator compressor according to claim 1 or 2, characterized in that setting the 48～52Hz.