JP2010239759A - Control device of one-piston rotary compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inverter control device which performs stable torque control without an operation stop by step-out due to erroneous detection of a position of a magnetic pole against an increase of a regeneration zone at overloading, in a control device of a one-piston rotary compressor using a brushless DC motor. <P>SOLUTION: A torque gain setting means 12 is provided for detecting the frequency of regeneration voltage detection by a regeneration voltage detection means 11, and setting a torque gain on the basis of the detected value, and a detection zone of the position of the magnetic pole is secured by varying a motor energization angle. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an inverter control device aimed at stabilizing control of a one-piston rotary compressor.

  As motor control devices for controlling the number of rotations of a brushless DC motor, there are a conventional 120 ° energization control method (see Patent Document 1) and a sine wave 180 ° energization control (see Patent Documents 2 and 3).

In the motor drive by the conventional brushless DC motor driving device shown in FIG. 3, the brushless DC motor exhibits its original torque performance and good speed control when the load torque applied to the brushless DC motor is a small torque. The performance and the speed followability are good even for a considerable speed pulsation, and it is possible to secure a sufficient high speed response. Since the configuration of the control circuit and the motor operation program are simple, there is a great merit that the cost of the entire system including the control circuit can be reduced.
Japanese Patent No. 2642357 JP 7-245982 A Japanese Patent Laid-Open No. 7-337079

  However, current continues to flow through the motor for a while even after energization is completed by opening and closing the switching element. This phenomenon is called regeneration, and the voltage generated at that time is called regeneration voltage. When the load on the compressor becomes heavy and the current increases, this regeneration section increases, the section for detecting the induced voltage of the motor becomes narrow, the magnetic pole position cannot be detected, and the step-out step occurs.

  The present invention solves the above-described conventional problems, and detects a regenerative voltage at certain intervals and adjusts the torque gain amount according to the number of detections to reduce the energization angle of the motor, thereby avoiding an overload condition. An object of the present invention is to provide a highly reliable control device for a one-piston rotary compressor that is free from step-out due to erroneous detection of the magnetic pole position.

In order to solve the above-mentioned conventional problems, the present invention detects a regenerative voltage at certain intervals and attempts to adjust a torque gain amount from the number of detection times.
Thereby, even when the regenerative section increases when the brushless DC motor 1 is overloaded, a magnetic pole position detection section is secured, and a highly reliable control device for a one-piston rotary compressor without step-out due to erroneous detection can be provided. .

  It is possible to provide a highly reliable control device for a one-piston rotary compressor in which regenerative voltage detection means is provided and the torque gain amount is adjusted based on the detected value so that step-out due to erroneous detection of the magnetic pole position does not occur.

  In the first invention, the brushless DC motor detects the regenerative voltage in the regenerative section at a certain time when the brushless DC motor is overloaded, adjusts the torque gain amount based on the detected value, and reduces the motor conduction angle. By shortening the regeneration section, it is possible to supply a highly reliable one-piston rotary compressor that does not cause step-out due to erroneous detection of the magnetic pole position.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a control block diagram of the present invention, and FIG. 2 is a graph showing its characteristics. A first embodiment of the present invention will be described with reference to FIGS.

  In FIG. 1, a regenerative voltage detecting means 11 for detecting the regenerative voltage of the DC / AC converting means 2 is provided in the configuration of FIG. 3 of the conventional example, and a torque gain adjusting means 12 for adjusting the torque gain based on the detected number of times. The torque gain adjustment amount is fed back to the voltage control means 9.

The torque gain adjusting means 12 increases the torque gain in proportion to the number of regenerative voltage detections when the number of regenerative voltage detections obtained from the regenerative voltage detection means 11 exceeds a certain number A1. Further, the energization angle is increased / decreased by the following equation by increasing / decreasing the torque gain.
iang _{n + 1} = ang _n −G (nrcv _n −1) Equation 1
iang is the energization angle, G is the torque gain, and nrcv is the number of times of regenerative voltage detection obtained from the regenerative voltage detection means.

  When the number of regenerative voltage detections is small as shown in FIGS. 2A and 2B, the torque gain adjustment amount is made constant at G1. From Equation 1, the energization angle gradually decreases as the number of regenerative voltage detections increases. While the regenerative section is short, there is no problem with the deceleration speed of Equation 1, but when the regenerative section spreads and the number of detections exceeds A1, control is performed to increase the torque gain with a certain slope and accelerate the decrease in the energization angle. By doing so, the overload condition can be reduced, the regenerative section can be reduced, the magnetic pole position detection section can be secured, and stable torque control operation of the one-piston rotary compressor can be performed without causing a step-out due to erroneous position detection. It can be carried out.

  The present invention relates to a rotation control technology of a motor (for example, a DC brushless motor) used for a compressor (compressor) of an air conditioner, and can avoid operation stop due to step-out due to erroneous detection of the magnetic pole position of the motor. In addition to the air conditioner, the present invention can be widely applied to refrigeration / refrigeration equipment such as a refrigerator using a compressor.

Control block diagram of 1-piston rotary compressor in Embodiment 1 of the present invention (A) The graph which showed the change of the adjustment amount of the torque gain of the control apparatus of 1 piston rotary compressor in Embodiment 1 of this invention (b) The graph which showed the change of the adjustment amount of the motor conduction angle same as the above Drive control block diagram of a conventional one-piston rotary compressor

DESCRIPTION OF SYMBOLS 1 AC power supply 2 Reactor 3 Diode bridge 4 Microcomputer 5 DC alternating current conversion means 6 1 Piston rotary compressor 7 Brushless DC motor 8 Induced voltage detection means 9 Voltage control means 10 PWM control means 11 Regenerative voltage detection means 12 Torque gain adjustment means

Claims (1)

A one-piston rotary compressor connected to a brushless DC motor, a DC / AC converter that includes a switching element, converts a DC voltage into an AC voltage based on a PWM signal by opening and closing the switching element, and supplies the AC voltage to the brushless DC motor; Inductive voltage detection means for detecting the induced voltage of the motor, voltage control means for outputting a voltage waveform based on magnetic pole position information output from the induced voltage detection means, and PWM control for converting the voltage waveform to the PWM signal A brushless DC motor control device having a regenerative phenomenon in which a current flows even after the energization of the torque gain of the brushless DC motor is ended by opening and closing of a switching element with respect to a rotational load torque fluctuation of the one-piston rotary compressor. The generated regenerative voltage is Detected at every predetermined time, the control apparatus of the first piston rotary compressor and sets on the basis of the detected number of times.

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