JP2007330012A - Refrigerator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that a compressor vibrates unstably, due to that sometimes the torque power leading to the stabilization of motor drive is not reached even if energizing angle is maximized during high-speed operation of the compressor immediately after power ON while the ambient temperature of a refrigerator is high (for example, 30°C or over) or after defrosting, and a current flowing to the motor of the compressor is disturbed. <P>SOLUTION: There are provided an energizing angle limit determination part 100, a bus voltage detector 101, a bus voltage value determination part 102, a counter 103, and an abnormal-voltage count determination part 104, so that the refrigerator can prevent the disturbance of the current flowing to the motor of the compressor by being changed into a drive system according to the rotational position of the rotor when the cooling load value of the refrigerator is large and that the torque output leading to the stabilization of the motor drive of the compressor is not reached due to the large cooling load value of the refrigerator. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  More particularly, the present invention relates to a brushless DC motor comprising a rotor having a permanent magnet and a stator having a three-phase winding. More particularly, the present invention relates to a method and apparatus for driving a brushless DC motor that is optimal for driving a compressor of a refrigerator.

  Conventionally, this kind of refrigerator is disclosed (for example, refer to patent documents 1).

  FIG. 11 is a longitudinal sectional view of a conventional refrigerator described in Patent Document 1, and FIG. 12 is a block diagram showing a conventional refrigerator control device. As shown in FIGS. 11 and 12, a refrigerator main body 1 and a refrigerator compartment 2 and a freezer compartment 3 are formed therein. The evaporator 4 is an evaporator that cools the freezer compartment 3. The compressor 5 is driven by the compressor driving means 6 while varying the operation speed, and the refrigerant is circulated to the evaporator 4 by a refrigeration cycle (not shown) to ensure the refrigerating capacity of the evaporator, and the operation speed is variable. The blower 7 sends cold air to the refrigerator compartment 2 or the freezer compartment 3 by the blower driving means 8. The heater 9 is a defrosting heater of the evaporator 4 and is energized by the heater driving means 10 when defrosting. The interior lamp 11 is installed inside the refrigerator compartment 2 and is energized by the interior lamp driving means 12 when the door of the refrigerator compartment 2 is opened. These operations are performed based on commands from the control means 13.

  FIG. 13 is a detailed block diagram of the conventional compressor driving means 6 for driving the brushless DC motor inside the compressor 5 when it is driven by the first waveform generating unit or the second waveform generating unit and when switching between both waveform generating units. It is a block diagram of an apparatus.

  In FIG. 13, the commercial power source 15 is an AC power source having a frequency of 50 Hz or 60 Hz and a voltage of 100 V in Japan.

  The rectifier circuit 14 converts the AC voltage of the commercial power supply 15 into a DC voltage. The rectifier circuit 14 includes bridge-connected rectifier diodes 14a to 14d, smoothing electrolytic capacitors 14e and 14f, and a voltage regulator circuit 14g. In the case of the voltage doubler rectifier circuit, the circuit shown in FIG. From this, a DC voltage of 280V can be obtained. Although voltage doubler rectification is used here, the voltage adjustment circuit 14g corresponds to a DC voltage variable chopper circuit or a voltage doubler rectification / full wave rectification switching type circuit.

  The inverter circuit 16 has a three-phase bridge configuration including six switch elements 15a, 15b, 15c, 15d, 15e, and 15f. Each switch element includes a diode for return current in the reverse direction of each switch element, but this is omitted in the figure.

  The brushless DC motor 17 includes a rotor 17a having a permanent magnet and a stator 17b having a three-phase winding. When the three-phase alternating current generated by the inverter 16 flows through the three-phase winding of the stator 17b, the rotor 17a can be rotated. The rotational movement of the rotor 17a is changed to a reciprocating movement by a crankshaft (not shown), and a piston (not shown) reciprocates in a cylinder (not shown) to compress the refrigerant. Drive.

  The load detection circuit 18 can detect the rotational relative position of the rotor 17a from the counter electromotive voltage generated when the rotor 17a having the permanent magnet of the brushless DC motor 17 rotates. In addition to detecting the rotation relative position, it is also possible to detect disturbances in the motor current and changes in the load state by detecting an increase or decrease in the time during which the current flows through the return current diode. From these detections, the advance degree of the motor current phase can be known.

  In this case, the rotation relative position of the rotor 17a is detected from the counter electromotive voltage generated by the rotation of the rotor 17a. However, the means for detecting the position of the rotor 17a and the state of the motor current is used. If so, a configuration using means such as current detection may be used.

  The first waveform generation unit 19 performs logical signal conversion based on the position detection signal of the load detection circuit 18 and generates signals for driving the switch elements 16a, 16b, 16c, 16d, 16e, and 16f of the inverter 16. This driving signal is based on rectangular wave energization, and generates a rectangular wave with an energization angle of 120 degrees or more and less than 180 degrees. In addition to the rectangular wave, a trapezoidal wave having a slight inclination in rising / falling may be used as a waveform conforming thereto. Further, in order to keep the rotation speed constant, duty control of PWM control and energization angle control are also performed. According to the rotational position, the actual rotational speed of the brushless DC motor 17 can be detected and operated with an optimum duty while comparing with the target rotational speed, so that the most efficient operation is possible. The detection of the actual rotational speed can be realized by counting the output signal of the load detection circuit 18 for a certain time or measuring the period. It is a waveform generating means suitable for a low-rotation operation region where high efficiency and low vibration are required.

  The second waveform generator 20 generates a signal for driving the switch elements 16a, 16b, 16c, 16d, 16e, and 16f of the inverter 16 by changing the output frequency and the conduction angle while keeping the duty constant. This driving signal creates a rectangular wave with a conduction angle of less than 180 degrees. In addition to the rectangular wave, a waveform conforming thereto such as a sine wave or a distorted wave may be used. This is a waveform generating means suitable for a high rotation operation region where high torque is required.

  The switching determination unit 21 includes the rotation number calculated by the first waveform generation unit 19, the duty controlled based on the rotation number, the frequency controlled by the second waveform generation unit 20, and the load detection circuit 18. Determines the operating state of the brushless DC motor 17 based on factors such as the magnetic pole position information of the rotor 17a detected by the motor, the phase information of the motor current, and the temperature state of the system in applications such as a refrigerator, and the waveform for operating the inverter 16 The first waveform generator 19 or the second waveform generator 20 is selected and switched. For example, when the rotational speed is low, the signal from the first waveform generator 19 is selected, and when the rotational speed is high, the signal from the second waveform generator 20 is selected to operate the inverter 16.

  The drive unit 22 drives the switch elements 16a, 16b, 16c, 16d, 16e, and 16f of the inverter 16 based on the output signal from the switching determination unit 21. By this driving, an optimal AC output can be applied from the inverter 16 to the brushless DC motor 17, so that the rotor 17a can be rotated.

  The microcomputer 23 implements the above functions. These functions can be realized by a microcomputer program.

  Next, the operation in FIG. 13 will be described with reference to FIGS.

  FIG. 14 is a flowchart showing the operation during driving by the conventional second waveform generator.

  Here, STEP1 to STEP4 are processes performed by the second waveform generator.

  First, in STEP 1, it is determined based on a signal output from the load detection circuit 18 whether the phase of the motor current with respect to the magnetic pole position of the rotor 4 a is advanced, delayed, or unstable. As a result of the determination, if the phase is unstable, the process proceeds to STEP2, and if the phase is delayed, the process proceeds to STEP3. If the phase is advanced, return to start.

  Next, in STEP2, the energization angle is enlarged and the process proceeds to STEP4.

  In STEP 3, the energization angle is reduced and the process proceeds to STEP 4.

Finally, in STEP4, an arbitrary time is waited until the motor behavior is stabilized. This is because even if the energization angle is adjusted, it does not immediately become “advancing state with a stable current phase”, so this process is necessary in order to wait for a sufficient time until the motor behavior becomes stable. . However, this waiting time can be omitted by slowly performing the energization angle adjustment process of STEP2 and STEP3, that is, by changing the energization angle very finely.
JP 2005-176437 A

  However, in the conventional configuration, when the motor current phase is unstable, such as when the refrigerator is under a high load / low voltage environment, the energization angle is expanded to further advance the phase and ensure the stabilization of the motor drive. Torque can be output, the phase can be further advanced and motor drive stability can be ensured, and a large torque can be output, but in situations where the ambient temperature of the refrigerator is high (for example, 30 ° C or higher) In extremely high cooling load situations such as during high-speed operation of the compressor immediately after power-on or after defrosting, the torque output does not reach the torque output that stabilizes the motor drive even if the energization angle is increased to the maximum. If this happens, the current flowing to the compressor motor will be disturbed, causing the compressor to vibrate in an unstable manner, causing the refrigerator housing to shake, and at the same time disturbing the power supply voltage. Interior light is the load of the refrigerator of the AC voltage system heater heating flickering had a problem that there is a problem that unstable by.

  The present invention solves the above-described conventional problems, and detects the load state of the refrigerator by checking the motor bus voltage in a situation where the compressor of the refrigerator is driven at a high rotation speed and further increases the conduction angle. It is another object of the present invention to provide a brushless DC motor driving method and a refrigerator equipped with the device, which can change the compressor driving method to a driving method according to the rotational position of the rotor.

  Another object of the present invention is to detect the load condition of the refrigerator by checking the motor bus voltage when the compressor of the refrigerator is driven at high rotation and further increases the energization angle to the maximum, and the operating speed of the blower is determined. It aims at providing the refrigerator provided with the control means which can be lowered | hung.

  In order to solve the above-mentioned conventional problems, the refrigerator of the present invention changes the predetermined frequency, operates the compressor while outputting a waveform with a conduction angle of less than 180 degrees in synchronization with the frequency, and detects the voltage value. When the voltage value detected by the circuit reaches a predetermined upper limit value or more, the switching determination unit selects and changes the driving method to output a waveform with a conduction angle of 150 degrees or less according to the rotation position of the rotor by the overload determination means. A drive unit for a brushless DC motor is provided.

  In the refrigerator of the present invention, the voltage value detected by the voltage value detection circuit is regulated while changing the predetermined frequency and operating the compressor while outputting a waveform with a conduction angle of less than 180 degrees in synchronization with the frequency. A brushless DC motor drive device is provided in which the switching determination unit selects and changes the drive method to output a waveform with a conduction angle of 150 degrees or less according to the rotational position of the rotor by the overload determination means when the lower limit value is reached. It is a thing.

  In the refrigerator of the present invention, the voltage value detected by the voltage value detection circuit is regulated while changing the predetermined frequency and operating the compressor while outputting a waveform with a conduction angle of less than 180 degrees in synchronization with the frequency. When the number of times reaching the upper limit value or below the specified lower limit value exceeds a certain number of times, the overload judgment means switches to a drive system that outputs a waveform with a conduction angle of 150 degrees or less according to the rotational position of the rotor A brushless DC motor driving device that is selected and changed by the determination unit is provided.

  In the refrigerator of the present invention, the voltage value detected by the voltage value detection circuit is regulated while changing the predetermined frequency and operating the compressor while outputting a waveform with a conduction angle of less than 180 degrees in synchronization with the frequency. When the time that reaches the upper limit value or below the specified lower limit value exceeds a certain time, the overload judgment means switches to a drive system that outputs a waveform with a conduction angle of 150 degrees or less according to the rotational position of the rotor. A brushless DC motor driving device that is selected and changed by the determination unit is provided.

  As a result, when the cooling load of the refrigerator is large and the torque output leading to stabilization of the compressor motor drive is not achieved, the drive system is changed to a drive system corresponding to the rotational position of the rotor, thereby disturbing the current flowing to the compressor motor. Can be prevented.

  In the refrigerator of the present invention, the voltage value detected by the voltage value detection circuit is regulated while changing the predetermined frequency and operating the compressor while outputting a waveform with a conduction angle of less than 180 degrees in synchronization with the frequency. When the number of times reaching the upper limit value or below the specified lower limit value is equal to or greater than a certain number, a control device is provided for lowering the operating rotational speed of the blower by the overload determining means.

  In the refrigerator of the present invention, the voltage value detected by the voltage value detection circuit is regulated while changing the predetermined frequency and operating the compressor while outputting a waveform with a conduction angle of less than 180 degrees in synchronization with the frequency. A control device is provided for lowering the operating rotational speed of the blower by the overload determining means when the time that has reached the upper limit value or below the specified lower limit value has reached a certain time or longer.

  Thereby, when the load of a refrigerator is high, the cooling load amount by an evaporator can be reduced by reducing the driving | running rotation speed of a fan.

  The refrigerator of the present invention is a compressor even when the cooling load is extremely large such as immediately after turning on the power in a situation where the ambient temperature of the refrigerator is high (for example, 30 ° C. or more) and during high-speed operation of the compressor after performing the defrosting operation. The motor current can be prevented from being disturbed and unstable vibration, that is, the refrigerator casing can be prevented from being shaken, and at the same time, the interior lamp and heater heat generated by the disturbed power supply voltage can be stabilized.

  According to the first aspect of the present invention, a compressor having a variable operating rotational speed, a refrigeration cycle including a drive means for the compressor and an evaporator for heat exchange, and cool air generated by the evaporator are sent into a warehouse. The operating speed variable type blower, the compressor and the drive means of the compressor are a brushless DC motor including a rotor having a permanent magnet and a stator having a three-phase winding, and power to the three-phase winding. An inverter to be supplied; a voltage value detection circuit for detecting a voltage value supplied to the three-phase winding; a load detection circuit for detecting a load state of the motor from motor operation state information; and a rotational position of the rotor. In response, a first waveform generator that outputs a waveform with a conduction angle of 150 degrees or less, a second waveform generator that changes a predetermined frequency and outputs a waveform with a conduction angle of less than 180 degrees in synchronization with the frequency, One waveform generator and the second A switching determination unit that switches between the shape generation unit and the motor according to the operating state of the motor, the switching determination unit is selecting the second waveform generation unit, and the voltage value detected by the voltage value detection circuit is a predetermined upper limit value. When the above is reached, a situation in which the ambient temperature of the refrigerator is high (for example, 30 ° C. or higher) by providing a drive unit for the brushless DC motor in which the switching determination unit selects the first waveform generation unit by the overload determination unit. Even in situations where the cooling load is extremely large, such as during high-speed operation of the compressor immediately after the power is turned on and after the defrosting operation, the motor of the compressor can be changed by changing the drive system according to the rotational position of the rotor. Can be prevented, unstable vibration of the compressor, that is, shaking of the refrigerator casing, can be suppressed, and the interior lamp and heater heat can be stabilized.

  According to a second aspect of the present invention, a compressor having a variable operating rotational speed, a refrigeration cycle including a drive means for the compressor and an evaporator for heat exchange, and cold air generated by the evaporator are sent into a warehouse. The operating speed variable type blower, the compressor and the drive means of the compressor are a brushless DC motor including a rotor having a permanent magnet and a stator having a three-phase winding, and power to the three-phase winding. An inverter to be supplied; a voltage value detection circuit for detecting a voltage value supplied to the three-phase winding; a load detection circuit for detecting a load state of the motor from motor operation state information; and a rotational position of the rotor. In response, a first waveform generator that outputs a waveform with a conduction angle of 150 degrees or less, a second waveform generator that changes a predetermined frequency and outputs a waveform with a conduction angle of less than 180 degrees in synchronization with the frequency, One waveform generator and the second A switching determination unit that switches between the shape generation unit and the motor operating state, the switching determination unit is selecting the second waveform generation unit, and the voltage value detected by the voltage value detection circuit is a specified lower limit value When the following is reached, a situation in which the ambient temperature of the refrigerator is high (for example, 30 ° C. or more) by providing a driving device for the brushless DC motor in which the switching determination unit selects the first waveform generation unit by the overload determination unit Even in situations where the cooling load is extremely large, such as during high-speed operation of the compressor immediately after the power is turned on and after the defrosting operation, the motor of the compressor can be changed by changing the drive system according to the rotational position of the rotor. Can be prevented, unstable vibration of the compressor, that is, shaking of the refrigerator casing, can be suppressed, and the interior lamp and heater heat can be stabilized.

  According to a third aspect of the present invention, the switching determination unit selects the second waveform generation unit, and the voltage value detected by the voltage value detection circuit reaches a specified upper limit value or less or a specified lower limit value or less. When the number of times of the determination is equal to or greater than a certain number of times, the overload determination means is provided with a brushless DC motor drive device for selecting the first waveform generation unit by the switching determination unit, so that the ambient temperature of the refrigerator is high ( Even in situations where the cooling load is extremely large, such as immediately after turning on the power at 30 ° C. or higher and during high-speed operation of the compressor after defrosting, the drive system should be changed according to the rotational position of the rotor. Thus, it is possible to prevent disturbance of the current flowing through the motor of the compressor, to suppress unstable vibration of the compressor, that is, to shake the casing of the refrigerator, and to stabilize the heating of the interior lamp and the heater.

  According to a fourth aspect of the present invention, the switching determination unit is selecting the second waveform generation unit, and the voltage value detected by the voltage value detection circuit reaches a specified upper limit value or less or a specified lower limit value or less. When the measured time becomes equal to or longer than a certain time, a drive device for the brushless DC motor that selects the first waveform generation unit by the switching determination unit by the overload determination unit is provided, so that the ambient temperature of the refrigerator is high ( Even in situations where the cooling load is extremely large, such as immediately after turning on the power at 30 ° C. or higher and during high-speed operation of the compressor after defrosting, the drive system should be changed according to the rotational position of the rotor. Thus, it is possible to prevent disturbance of the current flowing through the motor of the compressor, to suppress unstable vibration of the compressor, that is, to shake the casing of the refrigerator, and to stabilize the heating of the interior lamp and the heater.

  According to a fifth aspect of the present invention, the switching determination unit is selecting the second waveform generation unit, and the voltage value detected by the voltage value detection circuit reaches a specified upper limit value or less or a specified lower limit value or less. When the number of times of the operation has become a certain number of times or more, by providing a determination means of the control device that lowers the operating speed of the blower, immediately after turning on the power in a situation where the ambient temperature of the refrigerator is high (for example, 30 ° C. or more) Even under extremely high cooling load conditions such as during high-speed operation of the compressor after defrosting, the cooling load by the evaporator is reduced by lowering the operating speed of the blower and flows to the compressor motor It can prevent current disturbance, suppress unstable vibration of the compressor, that is, shake of the refrigerator casing, and stabilize the heat of the interior lamp and heater.

  According to a sixth aspect of the invention, the switching determination unit is selecting the second waveform generation unit, and the voltage value detected by the voltage value detection circuit reaches a specified upper limit value or less or a specified lower limit value or less. When the measured time becomes equal to or longer than a certain time, by providing a determination means of the control device that lowers the operating speed of the blower, immediately after turning on the power in a situation where the ambient temperature of the refrigerator is high (for example, 30 ° C. or higher) Even under extremely high cooling load conditions such as during high-speed operation of the compressor after defrosting, the cooling load by the evaporator is reduced by lowering the operating speed of the blower and flows to the compressor motor It can prevent current disturbance, suppress unstable vibration of the compressor, that is, shake of the refrigerator casing, and stabilize the heat of the interior lamp and heater.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the same reference numerals are given to the same configurations as those of the conventional example or the above-described embodiments, and detailed description thereof will be omitted. The present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a detailed block diagram of the compressor driving means 6 according to the first embodiment of the present invention, and shows compression related to driving by the first waveform generator 19 or the second waveform generator 20 and switching of both waveform generators. 3 is a block diagram of a brushless DC motor driving device inside the machine 5. FIG.

  The energization angle limit determination unit 100 is a determination unit that determines when the switching determination unit 21 is selecting the second waveform generation unit 20 and the energization angle is maximum and the inverter 16 is being driven. The bus voltage detector 101 detects a voltage value obtained by converting the AC voltage of the commercial power supply 15 into a DC voltage by the rectifier circuit 14. The bus voltage value determination unit 102 is configured such that the bus voltage detection unit 101 is equal to or higher than a certain voltage value (for example, 280 + aV or more, a is an arbitrary constant) with respect to a reference voltage value (for example, 280V), or less than a certain voltage value (for example, 280−bV). Hereinafter, b is a determination means for counting up the counter 103 when an arbitrary constant) is detected. The abnormal voltage number determination unit 104 is a determination unit that determines whether the number of times counted by the counter 103 has reached a predetermined value (for example, α times, α is an arbitrary constant) or more.

  About the refrigerator comprised as mentioned above, the operation | movement and the effect | action are the flowchart which shows the operation | movement of the same embodiment of FIG. 2 below, and the reference voltage value in the same embodiment of FIG. A description will be given based on the figure showing the case of the above.

  In FIG. 2, STEP 1 and STEP 3 are the same as the conventional example. Next, in STEP2, the energization angle is enlarged and the process proceeds to STEP101. In STEP 101, as shown in FIG. 3A, the bus voltage value determining unit 102 determines that the voltage value is less than a certain voltage value (for example, less than 280 + aV, for example, a is arbitrary) with respect to the reference voltage value (for example, 280V). ) And a value greater than a certain voltage value (for example, a value greater than 280-bV, b is an arbitrary constant), the process proceeds to STEP 103, as shown in FIG. The bus voltage detection unit 101 is equal to or higher than a predetermined voltage value (for example, 280 + aV or higher, a is an arbitrary constant) or lower than a predetermined voltage value (for example, 280−bV or lower, b is an arbitrary constant) with respect to a reference voltage value (for example, 280V). If any of the above is detected, the process proceeds to STEP 102 and the counter 103 is incremented, and the process proceeds to STEP 103. In STEP 103, if the number of times the counter 103 is counted by the voltage abnormality frequency determination unit 104 is less than a specified value (for example, α times, α is an arbitrary constant), the process proceeds to STEP 4, and the specified value (for example, α times, α is an arbitrary constant). If it is determined that the above has been reached, the process proceeds to STEP 104. In STEP 104, if the second waveform generation unit 20 has not reached the maximum energization angle by the energization angle limit determination unit 100, the process proceeds to STEP 4, and if it has reached the maximum energization angle, the process proceeds to STEP 105 and the switching determination unit 21 generates the second waveform. The selection is switched from the unit 20 to the first waveform generation unit 19, and the process proceeds to STEP4. After STEP4, it is the same as the conventional example.

  As described above, in the first embodiment, the conventional refrigerator is provided with the conduction angle limit determination unit 100, the bus voltage detection unit 101, the bus voltage value determination unit 102, the counter 103, and the abnormal voltage frequency determination unit 104. By changing the predetermined frequency, synchronizing the frequency and outputting a waveform with a conduction angle of less than 180 degrees, the compressor is operating and the voltage value detected by the voltage value detection circuit reaches the specified upper limit value or more. In this case, the brushless DC motor driving device is selected and changed by the switching determination unit to the driving method in which the overload determination unit outputs a waveform having a conduction angle of 150 degrees or less according to the rotational position of the rotor.

  Further, in the first embodiment, the voltage value detected by the voltage value detection circuit is changed while the compressor is operating while changing the predetermined frequency and outputting a waveform with a conduction angle of less than 180 degrees in synchronization with the frequency. A brushless DC motor drive device in which the switching determination unit selectively changes to a drive system that outputs a waveform with a conduction angle of 150 degrees or less according to the rotational position of the rotor by the overload determination means when the specified lower limit value is reached; Become.

  Further, in the first embodiment, the voltage value detected by the voltage value detection circuit is changed while the compressor is operating while changing the predetermined frequency and outputting a waveform with a conduction angle of less than 180 degrees in synchronization with the frequency. When the number of times the specified upper limit value or more or the specified lower limit value is reached is more than a certain number, the overload judging means outputs a waveform with a conduction angle of 150 degrees or less according to the rotational position of the rotor. The switching determination unit is a brushless DC motor driving device that is selected and changed.

  Further, in the first embodiment, the voltage value detected by the voltage value detection circuit is changed while the compressor is operating while changing the predetermined frequency and outputting a waveform with a conduction angle of less than 180 degrees in synchronization with the frequency. To a drive system that outputs a waveform with a conduction angle of 150 degrees or less according to the rotational position of the rotor by the overload judging means when the time that has reached the specified upper limit value or less or the specified lower limit value has reached a certain time or longer. The switching determination unit is a brushless DC motor driving device that is selected and changed.

  As a result, when the cooling load of the refrigerator is large and the torque output leading to stabilization of the compressor motor drive is not achieved, the drive system is changed to a drive system corresponding to the rotational position of the rotor, thereby disturbing the current flowing to the compressor motor. Can be prevented.

(Embodiment 2)
FIG. 4 is a detailed block diagram of the compressor driving means 6 according to the second embodiment of the present invention. The compression is performed when the first waveform generator 19 or the second waveform generator 20 is driven and when both waveform generators are switched. 3 is a block diagram of a brushless DC motor driving device inside the machine 5. FIG. 4 that are the same as those in FIG. 1 have already been described, and will not be described.

  The bus voltage value determination unit 200 is configured such that the bus voltage detection unit 101 is equal to or higher than a certain voltage value (for example, 280 + aV or more, a is an arbitrary constant) with respect to a reference voltage value (for example, 280V), or less than a certain voltage value (for example, 280−bV). Hereinafter, b is a determination means for starting the timer 201 when an arbitrary constant) is detected. The abnormal voltage time determination unit 202 is a determination unit that determines whether the time counted by the timer 201 has reached a specified time (for example, β seconds, β is an arbitrary constant) or more.

  About the refrigerator comprised as mentioned above, the operation | movement and an effect | action are the flowchart which shows the operation | movement of the same embodiment of FIG. 5 below, and the reference voltage value in the same embodiment of FIG. A description will be given based on the figure showing the case of the above.

  In FIG. 5, STEP 1 to STEP 3 are the same as in the first embodiment. In STEP 101, as shown in FIG. 6A, the bus voltage detection unit 102 determines that the voltage value is less than a certain voltage value (for example, less than 280 + aV, for example), and a is an arbitrary value. ) And a value greater than a certain voltage value (for example, a value greater than 280-bV, b is an arbitrary constant), the process proceeds to STEP 202, as shown in FIG. The bus voltage detection unit 101 is equal to or higher than a predetermined voltage value (for example, 280 + aV or higher, a is an arbitrary constant) or lower than a predetermined voltage value (for example, 280−bV or lower, b is an arbitrary constant) with respect to a reference voltage value (for example, 280V). If any of the above is detected, the process proceeds to STEP 201, the timer 201 is started, and the process proceeds to STEP 202. In STEP 202, if the time of the timer 201 is less than a predetermined value (for example, β seconds, β is an arbitrary constant) by the abnormal voltage time determination unit 202, the process proceeds to STEP 4, and exceeds the specified value (for example, β seconds, β is an arbitrary constant). If it is determined that it has reached, the process proceeds to STEP 104. Step 4 and subsequent steps are the same as in the first embodiment.

  As described above, in Embodiment 2, the conventional refrigerator is provided with the conduction angle limit determination unit 100, the bus voltage detection unit 101, the bus voltage value determination unit 200, the timer 201, and the abnormal voltage time determination unit 202. By changing the predetermined frequency, synchronizing the frequency and outputting a waveform with a conduction angle of less than 180 degrees, the compressor is operating, and the voltage value detected by the voltage value detection circuit is greater than or equal to the specified upper limit value or specified When the time when the value reaches the lower limit of the value becomes equal to or longer than a certain time, the switching determination unit selectively changes the drive method to output a waveform with a conduction angle of 150 degrees or less according to the rotation position of the rotor by the overload determination means. It becomes a drive device of a brushless DC motor.

  As a result, when the cooling load of the refrigerator is large and the torque output leading to stabilization of the compressor motor drive is not achieved, the drive system is changed to a drive system corresponding to the rotational position of the rotor, thereby disturbing the current flowing to the compressor motor. Can be prevented.

(Embodiment 3)
FIG. 7 is a detailed block diagram of the compressor driving means 6 according to the third embodiment of the present invention. The compression is performed when the first waveform generator 19 or the second waveform generator 20 is driven and when both waveform generators are switched. 3 is a block diagram of a brushless DC motor driving device inside the machine 5. FIG. 7 that are the same as those in FIG. 1 have already been described, and will not be described.

  The blower rotation speed determination unit 300 is a determination unit that performs a determination to lower the operation rotation speed of the blower 7 based on the determination of the abnormal voltage number determination unit 104.

  The operation and effect of the refrigerator configured as described above will be described below based on the flowchart showing the operation of the embodiment shown in FIG.

  In FIG. 8, first, STEP1 to STEP3, STEP101 and TSEP102 are the same as in the first embodiment. In STEP 103, if the number of times the counter 103 is counted by the voltage abnormality frequency determination unit 104 is less than a specified value (for example, α times, α is an arbitrary constant), the process proceeds to STEP 4, and the specified value (for example, α times, α is an arbitrary constant). When it determines with having reached above, it progresses to STEP301 and the signal which lowers the driving | running rotation speed of the air blower 7 is transmitted to the control means 13 by the air blower rotation speed determination part 300, and it progresses to STEP4. After STEP4, it is the same as the conventional example.

  As described above, in the third embodiment, the conventional refrigerator is provided with the bus voltage detection unit 101, the bus voltage value determination unit 102, the counter 103, the abnormal voltage number determination unit 104, and the fan rotation speed determination unit 300. By changing the predetermined frequency, synchronizing the frequency and outputting a waveform with a conduction angle of less than 180 degrees, the compressor is operating, and the voltage value detected by the voltage value detection circuit is greater than or equal to the specified upper limit value or specified When the number of times reaching below the lower limit of the number becomes a certain number of times or more, a control device is provided for lowering the operation speed of the blower by the overload determination means.

  Thereby, when the load of a refrigerator is high, the cooling load amount by an evaporator can be reduced by reducing the driving | running rotation speed of a fan.

(Embodiment 4)
FIG. 9 is a detailed block diagram of the compressor driving means 6 according to the fourth embodiment of the present invention. The compression is performed when the first waveform generating unit 19 or the second waveform generating unit 20 is driven and when both waveform generating units are switched. 3 is a block diagram of a brushless DC motor driving device inside the machine 5. FIG. 7 that are the same as those in FIG. 4 have already been described, and will not be described.

  The blower rotation speed determination unit 300 is a determination unit that determines to lower the operation rotation speed of the blower 7 based on the determination of the abnormal voltage time determination unit 202.

  About the refrigerator comprised as mentioned above, the operation | movement and an effect | action are demonstrated based on the flowchart which shows the operation | movement of the same embodiment of FIG. 10 below.

  In FIG. 10, first, STEP 1 to STEP 3, STEP 101, and TSEP 201 are the same as those in the second embodiment. In STEP 202, if the time of the timer 201 is less than a predetermined value (for example, β seconds, β is an arbitrary constant) by the abnormal voltage time determination unit 202, the process proceeds to STEP 4, and exceeds the specified value (for example, β seconds, β is an arbitrary constant). If it is determined that it has been reached, the process proceeds to STEP 401, where the blower rotation speed determination unit 300 transmits a signal for lowering the operation speed of the blower 7 to the control means 13, and the process proceeds to STEP 4. After STEP4, it is the same as the conventional example.

  As described above, in the third embodiment, the conventional refrigerator is provided with the bus voltage detection unit 101, the bus voltage value determination unit 102, the counter 103, the abnormal voltage number determination unit 104, and the fan rotation speed determination unit 300. By changing the predetermined frequency, synchronizing the frequency and outputting a waveform with a conduction angle of less than 180 degrees, the compressor is operating, and the voltage value detected by the voltage value detection circuit is greater than or equal to the specified upper limit value or specified A control device is provided for lowering the operating rotational speed of the blower by the overload determining means when the time that has reached the lower limit value of the above becomes a certain time or longer.

  Thereby, when the load of a refrigerator is high, the cooling load amount by an evaporator can be reduced by reducing the driving | running rotation speed of a fan.

  As described above, the brushless DC motor driving method and the refrigerator with the apparatus according to the present invention can exhibit effects such as noise and vibration reduction, prevention of step-out stop, and suppression of peak current generation. It can also be applied to various applications equipped with brushless DC motors for both home and industrial use.

The detailed block diagram of the compressor drive means of the refrigerator in Embodiment 1 of this invention The flowchart which shows operation | movement of Embodiment 1 of this invention. The figure which shows the case where it becomes more than a regulation value or below a regulation value with respect to the reference voltage value in Embodiment 1 of this invention. Detailed block diagram of the compressor driving means of the refrigerator in the second embodiment of the present invention The flowchart which shows operation | movement of Embodiment 2 of this invention. The figure which shows the case where it becomes more than a regulation value or below a regulation value with respect to the reference voltage value in Embodiment 2 of this invention. Detailed block diagram of the compressor driving means of the refrigerator in Embodiment 3 of the present invention The flowchart which shows operation | movement of Embodiment 3 of this invention. Detailed block diagram of the compressor drive means of the refrigerator in Embodiment 4 of the present invention The flowchart which shows operation | movement of Embodiment 4 of this invention. Vertical section of a conventional refrigerator Functional block diagram of a conventional refrigerator Detailed block diagram of conventional refrigerator compressor drive means A flowchart showing the operation at the time of driving by the conventional second waveform generator

Explanation of symbols

DESCRIPTION OF SYMBOLS 14 Rectification circuit 15 Commercial power supply 16 Inverter circuit 17 Brushless DC motor 18 Load detection circuit 19 1st waveform generation part 20 2nd waveform generation part 21 Switching determination part 22 Drive part 23 Microcomputer 100 Energization angle limit determination part 101 Bus voltage detection part 102 Bus Voltage Value Determination Unit 103 Counter 104 Abnormal Voltage Number Determination Unit 200 Bus Voltage Value Determination Unit 201 Timer 202 Abnormal Voltage Time Determination Unit 300 Blower Speed Determination Unit

Claims (6)

  A compressor having a variable operating speed, a refrigeration cycle including a driving means for the compressor and an evaporator for heat exchange, and a fan having a variable operating speed, which sends the cold air generated by the evaporator into the refrigerator. The compressor and the driving means of the compressor include a brushless DC motor including a rotor having a permanent magnet and a stator having a three-phase winding, an inverter for supplying electric power to the three-phase winding, and the three-phase winding A voltage value detection circuit for detecting a voltage value supplied to the wire, a load detection circuit for detecting a load state of the motor from the operation state information of the motor, and a waveform having a conduction angle of 150 degrees or less according to the rotational position of the rotor A first waveform generator for outputting a waveform, a second waveform generator for outputting a waveform with a conduction angle of less than 180 degrees in synchronization with the frequency while changing a predetermined frequency, the first waveform generator and the second waveform Generator and the motor A switching determination unit that switches depending on the operating state, when the switching determination unit is selecting the second waveform generation unit, and the voltage value detected by the voltage value detection circuit has reached a predetermined upper limit value, A refrigerator having a brushless DC motor driving device selected and changed by the switching determination unit in the first waveform generation unit.   A compressor having a variable operating speed, a refrigeration cycle including a driving means for the compressor and an evaporator for heat exchange, and a fan having a variable operating speed, which sends the cold air generated by the evaporator into the refrigerator. The compressor and the driving means of the compressor include a brushless DC motor including a rotor having a permanent magnet and a stator having a three-phase winding, an inverter for supplying electric power to the three-phase winding, and the three-phase winding A voltage value detection circuit for detecting a voltage value supplied to the wire, a load detection circuit for detecting a load state of the motor from the operation state information of the motor, and a waveform having a conduction angle of 150 degrees or less according to the rotational position of the rotor A first waveform generator for outputting a waveform, a second waveform generator for outputting a waveform with a conduction angle of less than 180 degrees in synchronization with the frequency while changing a predetermined frequency, the first waveform generator and the second waveform Generator and the motor A switching determination unit that switches depending on the operating state, when the switching determination unit is selecting the second waveform generation unit, and the voltage value detected by the voltage value detection circuit has reached a predetermined lower limit value, A refrigerator having a brushless DC motor driving device selected and changed by the switching determination unit in the first waveform generation unit.   The number of times that the switching determination unit is selecting the second waveform generation unit and the voltage value detected by the voltage value detection circuit has reached a specified upper limit value or less or a specified lower limit value or less has reached a certain number of times. 3. The refrigerator according to claim 1, wherein a determination unit of a brushless DC motor driving device selected and changed by the switching determination unit is provided in the first waveform generation unit.   The switching determination unit is selecting the second waveform generation unit, and the time when the voltage value detected by the voltage value detection circuit has reached a specified upper limit value or less or a specified lower limit value has become a certain time or more. 3. The refrigerator according to claim 1, further comprising a brushless DC motor driving device determining unit that selectively changes the switching determination unit to the first waveform generation unit.   The number of times that the switching determination unit is selecting the second waveform generation unit and the voltage value detected by the voltage value detection circuit has reached a specified upper limit value or less or a specified lower limit value or less has reached a certain number of times. 3. The refrigerator according to claim 1, further comprising a determination unit of a control device that lowers an operation rotational speed of the blower.   The switching determination unit is selecting the second waveform generation unit, and the time when the voltage value detected by the voltage value detection circuit has reached a specified upper limit value or less or a specified lower limit value has become a certain time or more. 3. The refrigerator according to claim 1, further comprising a determination unit of a control device that lowers an operation rotational speed of the blower.

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