JP2005137069A - Method for controlling starting of dc brushless motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for controlling starting of a DC brushless motor which can start certainly and rapidly the DC brushless motor for driving a compressor. <P>SOLUTION: In the method for controlling to start the DC brushless motor, if starting is failed when the DC brushless motor for the compressor is started, a starting parameter to the DC brushless motor is sequentially restarted while changing to data stored previously, the DC brushless motor is abnormally stopped when the number of times of this starting failures reaches a predetermined number of times. Thus, the DC brushless motor is surely started in a process of sequentially changing the combination of the starting parameters. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a DC brushless motor startup control technique used in an air conditioner or the like, and more particularly to a DC brushless motor startup control method that enables startup even at high loads.

  In the conventional start-up control of a DC brushless motor, an induced voltage generated in a non-energized phase of the DC brushless motor is detected to switch energization of the armature winding current of the DC brushless motor. Also, when starting the DC brushless motor, positioning control is performed to move and hold the magnetic pole position of the permanent magnet (rotor) at a fixed position. Change mode to detection operation.

  Therefore, the control device for the DC brushless motor converts AC power into DC power by an AC / DC converter (rectifier circuit), and switches this converted DC power by a switching element (transistor) of the inverter to convert the DC power to the DC brushless motor. Supply to the armature winding. The terminal voltage of the DC brushless motor is input to the position detection circuit. The position detection circuit compares the induced voltage with a reference voltage to obtain a rotor position detection signal, and outputs the position detection signal to the control circuit and the drive circuit. .

  Further, when starting the DC brushless motor, the control circuit drives on / off the plurality of switching elements of the inverter unit according to the energization pattern stored in advance, and switches the energization of the stator coil current of the DC brushless motor.

  As described above, when the DC brushless motor is started, positioning control and synchronous operation are performed, and when the induced voltage sufficient to detect the position of the rotor is generated, the mode shifts to the position detection operation mode described above. It is.

  Among these, a method for controlling the starting voltage is known as a control for particularly ensuring the starting (see, for example, Patent Document 1).

  Hereinafter, a conventional control method for ensuring start-up will be described.

  A voltage adjusting means for adjusting the starting voltage, a detecting means for detecting a starting failure at the time of starting, a counter for counting the number of times of starting failure, and a starting voltage sequentially for each predetermined voltage through the voltage adjusting means for each starting failure In addition to restarting the system, the system is stopped abnormally when the startup failure reaches a predetermined number of times.

JP-A-10-267432

  In the startup control of the conventional DC brushless motor, the startup voltage is sequentially increased and restarted to improve the reliability of the operation of the air conditioner. However, no other factors related to the start control are taken into consideration. In addition, the starting voltage at the time of starting failure after the DC brushless motor has stopped operating normally is always higher than the initial value, and even the next starting failure may fail the same number of times, resulting in a time loss.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide DC brushless motor activation control that reliably and quickly activates DC brushless motors widely used in air conditioners and the like.

  The start-up control of the DC brushless motor can be divided into four stages of control, positioning, synchronous operation, switching, and position detection operation immediately after switching. In addition, there are many possible causes of the DC brushless motor start failure, but at least as the main factors of control, the amount of current flowing to the motor rotor, the switching determination electric angle from the synchronous operation to the position detection operation, and the synchronous operation These are stored in the nonvolatile storage device as startup control parameters (hereinafter abbreviated as startup parameters), and the restart control is performed by sequentially changing the parameters when startup fails. At this time, when startup is successful, the parameters at that time are stored in the nonvolatile storage device, and when startup fails again, startup control is preferentially performed with the startup parameter value stored in the nonvolatile storage device. Further, when the activation fails, the number of failures is counted, and the activation parameter is updated and the activation control is performed again.

  According to the present invention, when starting a DC brushless motor for a compressor, when starting fails, the starting parameters for the DC brushless motor are sequentially restarted while changing to pre-stored data. Since the abnormal stop is made when the number of times is reached, the DC brushless motor can always be started in the process of sequentially changing the combination of the startup parameters, and thus the compressor can be started reliably, Even though the compressor itself has no abnormality, it is possible to eliminate the inconvenience of being in an abnormal stop. In addition, the DC brushless motor can be reliably started by preferentially using the combination of parameters at the time of successful restart and restarting even at high load. In the compressor, the operation reliability of the air conditioner can be further improved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a schematic configuration of an air conditioner to which the present invention is applied. The air conditioner in this case is composed of an outdoor unit 1 for generating a heat source necessary for air conditioning and an indoor unit 2 for blowing out air for air conditioning generated by the outdoor unit 1.

  The outdoor unit 1 is installed outside and has a compressor 11, a four-way switching valve 12, an outdoor air heat exchanger 13, and an expansion valve 15, and is connected to the indoor unit 2 via the liquid pipe 3 and the gas pipe 4. Connected. The indoor unit 2 is installed on the wall surface of the room and has an indoor air heat exchanger 21.

  In addition, a DC brushless motor 14 is connected to the compressor 11 of the outdoor unit 1 as a drive motor, and an activation control device 5 is connected to the DC brushless motor 14.

  The activation control device 5 includes a power source 51, a nonvolatile storage device 52, an NG detection unit 53, an NG counter 54, an activation control microcomputer 55, and an abnormal stop display unit 57.

  Here, the non-volatile storage device 52 includes at least a positioning energization current amount (hereinafter abbreviated as energization current amount) to the motor rotor, a switching determination electrical angle (hereinafter referred to as switching determination electricity) from synchronous operation to position detection operation. And an acceleration process at the time of synchronous operation (hereinafter abbreviated as an acceleration process), and an initial value, a restart value, and a restart value for each are stored in advance as data.

  The indoor unit 2 sends an activation signal from the indoor control device 22 to the activation control microcomputer 55 of the outdoor unit 1 by the operation of the remote controller 24 or the activation switch 23 inside the indoor control device 22, and the activation control microcomputer 55 is activated by the activation control device. The DC brushless motor 14 is started via 5.

  In the above configuration, when an activation control signal is transmitted from the indoor unit 2 to the outdoor unit 1, the flowchart shown in FIG.

  When the activation control signal is transmitted to the activation control microcomputer 55, the NG counter 54 is reset, and the DC brushless motor 14 is activated with a combination of the initial value data of the nonvolatile memory device 52 in step 201. If this is the case, the count number of the NG counter 54 is incremented by 1 in step 202, and the presence or absence of restart data is confirmed. If there is no restart data, restart is performed in step 203 with the initial value combination. . If the activation fails, the count number of the NG counter 54 is incremented by 1 in step 202, the count number, that is, the number of failures is compared, and it is assumed that two consecutive failures have occurred. In step 204, restart is performed. Further, if the restart fails, the count number of the NG counter 54 is further increased by 1 in step 202, and the stored current amount parameter is changed to the restart value. Restart with. Further, if the restart fails, in step 202, the count number of the NG counter 54 is further increased by 1, the parameter of the energization current amount is returned to the initial value, and the parameter value of the switching determination electric angle is changed to the restart value. In step 206, restart is performed. When the activation fails, the parameter value of the switching determination electrical angle is restarted (step 207), the parameter value of the switching determination electrical angle is returned to the initial value, and the acceleration processing parameter is restarted (step). 208) The acceleration processing parameter is changed to the restart value (step 209), and the restart is performed (step 202). When activation fails eight times in the above seven combinations, the abnormal stop display unit 57 displays the abnormal stop and notifies the outside of the air conditioner abnormally to perform an abnormal stop process.

  If the restart is successful in any one of the steps 203 to 209 of the restart, the combination of the energization current amount, the switching determination electrical angle, and the parameter of the acceleration process is stored in the nonvolatile storage device 52 as the stored data (step 220). ) If the activation fails again due to the initial value, the combination of the stored data is preferentially restarted (step 221).

The schematic block diagram of one Example of this invention. The flowchart explaining operation | movement of one Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Outdoor unit, 2 ... Indoor unit, 3 ... Liquid piping, 4 ... Gas piping, 5 ... Start-up control apparatus, 11 ... Compressor, 12 ... Four-way switching valve, 13 ... Outdoor air heat exchanger, 14 ... DC brushless motor , 15 ... expansion valve, 21 ... indoor air heat exchanger, 22 ... indoor control device, 23 ... start switch, 24 ... remote control, 51 ... power supply unit, 52 ... non-volatile storage device, 53 ... NG detection unit, 54 ... NG Counter, 55... Start control microcomputer, 57.

Claims (1)

When a compressor driven by a DC motor is installed and the AC power source is converted to a DC power source at startup, the converted DC power source is switched and applied to a sensorless DC brushless motor (hereinafter referred to as a DC brushless motor) in advance. In a DC brushless motor start control method for switching the conversion DC power supply according to a stored start pattern and starting the DC brushless motor, a detection means for detecting a start failure at the start, and a counter for counting the number of start failures As the start control parameters, at least the initial value, the restart value, and the restart are set for the positioning energization current amount to the motor rotor, the electrical angle for determining the switching from the synchronous operation to the position detection operation, and the acceleration process during the synchronous operation. The value is stored in a non-volatile storage device, and the parameter of the activation pattern for each activation failure When restarting succeeds, the startup parameters are stored in the non-volatile storage device, and when startup fails, the number of failures is counted, and when startup fails continuously a predetermined number of times A starting control method for a DC brushless motor, characterized by abnormally stopping.

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