JP2005102500A - Method of driving brushless motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a brushless motor with improved reliability in the brushless motor having a built-in power source circuit for a control circuit and a regulator. <P>SOLUTION: The brushless motor includes a stator core in which a plurality of stator windings are wound through an insulating layer, a permanent magnet rotor held rotatably at a bearing, and a printed circuit board which mounts a switching power element group 2, the control circuit 3, the power source circuit D for the control circuit, and the regulator 9. Only power for driving the motor is supplied to the motor. Power for the control circuit is generated from the power for driving the motor by using the power source circuit D for the control circuit contained in the motor and the regulator 9, and supplied. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a brushless motor in which only motor driving power is supplied to a motor, and control circuit unit power is generated and supplied from the motor driving power.

  The conventional brushless motor drive system has a configuration as shown in the block diagram of FIG. 2, and includes a brushless motor A incorporating a control circuit section and a switching power element group, and a motor drive power supply circuit section B such as a switching power supply. The control circuit power supply circuit part D is connected by at least three power supply lead wires.

  Further, the rotational speed of the brushless motor is varied by varying the output voltage of the motor driving power supply circuit section B.

  Hereinafter, an example of a conventional brushless motor drive system will be described with reference to the drawings.

  The brushless motor A includes a motor 1 having a stator winding (not shown), rotor position sensors 1a to 1c, and a drive current supplied to the stator winding of the motor so as to be divided by the one-dot chain line shown. The switching power element group 2 to be switched, a control circuit unit 3 that generates a signal for driving the switching power element group 2, and a noise prevention capacitor 10 are configured.

  The motor drive power supply circuit section B includes a commercial power supply 4, a rectifying / smoothing circuit section 5 composed of a diode, a capacitor, etc., and a DC-DC converter section C (transformer 6, switching power element 7 and voltage control circuit section 8. It is composed of.

  The control circuit power supply circuit section D is composed of a commercial power supply 4, a transformer 6, and an AC-DC converter section E (consisting of a regulator section 9 and other electronic components).

  The brushless motor A is connected to a motor driving power supply circuit section B such as a switching power supply and a control circuit power supply circuit section C by at least three power supply lead wires.

  An example of the operation of the conventional brushless motor drive system configured as described above will be described.

  In the motor drive power supply circuit section B, the input voltage of the commercial power supply 4 is rectified and smoothed by the rectifying and smoothing circuit section 5 and then the voltage is dropped by the switching power element 7 and the transformer 6 of the DC-DC converter section and supplied to the motor. Yes.

  In the power supply circuit section D for the control circuit section, the input voltage of the commercial power supply 4 is dropped by the transformer 6, rectified and smoothed by the diode and capacitor of the AC-DC converter section E, and stabilized and supplied by the regulator section 9. .

  In the conventional brushless motor drive system as described above, in order to obtain stable power for the control circuit section not only for the brushless motor but also for the control circuit and other circuits of the user's equipment, the user's The control circuit power supply circuit part D is required on the power supply board.

  Furthermore, in order to supply this to the brushless motor, a power supply lead is required.

  This means that when the system is focused on the relationship between the brushless motor and the power supply, space is required on the power supply board for the wiring of the transformer, regulator, other electronic components, and printed wiring board. In addition, the cost is higher by these amounts.

  Furthermore, if the power supply lead is long, voltage fluctuations due to the impedance and inductance of the power supply lead will occur, or noise from an external noise source will be induced and applied to the power supply voltage, affecting the controllability of the brushless motor. It sometimes leads to destruction.

  Therefore, in order to prevent this, it is necessary to insert a relatively large capacity noise prevention capacitor or the like into the power line of the control circuit section.

  As a result, these are major factors that increase the cost of the brushless motor.

  An object of the present invention is to provide a brushless motor that solves the above-described conventional problems, reduces system cost, contributes to space saving, and improves reliability.

  In order to achieve this object, the brushless motor of the present invention has the following configuration. A stator core in which a multi-phase stator winding is wound via an insulating layer, a permanent magnet rotor rotatably supported by a bearing, a rotor position sensor, and a drive current supplied to the stator winding A switching power element group for switching between and the output of the rotor position sensor to generate a signal for driving the switching power element group, and a power supply for the control circuit part for generating power supplied to the control circuit part A printed circuit board on which a regulator section for generating a reference voltage to be output to the circuit section and the power circuit for the control circuit section is mounted; only the motor driving power is supplied to the motor; and the motor driving power is The control circuit unit power generated by the voltage drop using the control circuit unit power supply circuit unit and the regulator unit incorporated in the control circuit unit is generated, and the control circuit unit power is supplied to the control circuit. And supplying the parts.

As described above, the brushless motor of the present invention can incorporate a control circuit power supply circuit in the motor with a relatively simple circuit configuration, and can stably supply control circuit power.
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In addition, since the power supply board for the user does not require a control circuit power supply circuit and the number of power supply leads is reduced, the cost of the power supply is reduced, and the system can be reduced in space and cost.

  In addition, since there is no power supply lead wire for the control circuit, the motor controllability is not affected by an external noise generation source, and the motor reliability can be improved such that a noise prevention capacitor is not necessary.

  As a result, the size and cost can be reduced, and the number of parts can be reduced, so that the reliability of the system can be improved.

  With the above configuration, the control circuit unit power supply circuit can be built in the motor with a relatively simple circuit configuration, and the control circuit unit power can be stably supplied.

  This eliminates the need for components of the power circuit for the control circuit section on the user's power board.

  Also, since only motor driving power needs to be supplied to the motor, the number of power supply leads is reduced.

  Furthermore, since there is no power supply lead wire for the control circuit section, it is not affected by the controllability of the motor by an external noise generation source, and a noise prevention capacitor is not necessary.

  An embodiment of the present invention will be described below with reference to the drawings.

  FIG. 1 is a block diagram of a brushless motor drive system according to the present invention.

  In the present invention, it is not necessary to supply power for the control circuit to the motor, as shown in comparison with the conventional system block diagram (FIG. 2). And not.

  Also, since only motor driving power needs to be supplied to the motor, the number of power supply leads is reduced.

  The same components as those shown in FIG. 2 are denoted by the same reference numerals, and description thereof is omitted.

  Next, the operation of this embodiment will be described.

  First, when motor driving power is supplied from the motor driving power supply circuit section B, the regulator section 9 operates to output a reference voltage, which is input to the control circuit power supply circuit section D.

  In this embodiment, the power supply circuit portion D for the control circuit portion is composed of the power transistor 11 and the resistance 12 for leakage prevention, and the control circuit portion drive voltage value + VBE of the power transistor 11 as the reference voltage, that is, 5. A voltage near 8 V is input to the base terminal of the power transistor 11.

Next, when the power transistor 11 is turned on, the voltage drops between the collector and the emitter, and 5.0 V, which is a control circuit section drive voltage value, is output to the emitter terminal.
By supplying this to the control circuit unit 3, the control circuit unit 3 operates to send an energization switching signal to the switching power element group 2 to drive the motor 1.

  At this time, since stable power is supplied to the control circuit unit 3, no noise prevention capacitor is required.

  Even if the voltage value for driving the motor is changed to change the rotation speed, the fluctuation is absorbed by the voltage drop between the collector and the emitter of the power transistor 11, and stable power is supplied to the control circuit unit 3. .

  Further, when the control circuit unit 3 includes a low voltage protection circuit (not shown), the control circuit unit 3 is turned off when the output of the power transistor 11 is equal to or lower than the voltage value required for driving the control circuit unit 3. Does not lead to abnormal operation.

  INDUSTRIAL APPLICABILITY The present invention is useful as a brushless motor in which only motor driving power is supplied to the motor, and control circuit power is generated from the motor driving power and supplied.

1 is a block diagram of a brushless motor drive system according to an embodiment of the present invention. Conventional brushless motor drive system block diagram

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Motor 2 Switching power element group 3 Control circuit part 4 Commercial power supply 5 Rectification smoothing circuit part 6 Transformer 7 Switching power element 8 Voltage control circuit part 9 Regulator part 10 Noise prevention capacitor 11 Power transistor 12 Leakage prevention resistor

Claims (4)

A stator core in which a multi-phase stator winding is wound via an insulating layer, a permanent magnet rotor rotatably supported by a bearing, a rotor position sensor, and a drive current supplied to the stator winding a switching power element group for switching the said rotor and a control circuit unit which positions the output of the sensor combined to generate a signal for driving the switching power element group, the control circuit section for generating a power supplied to the control circuit unit and use the power supply circuit unit, and a printed wiring board a reference voltage to implement a regulator unit for generating and outputting to the power supply circuit for the control circuit, the motor is supplied only power drive motor, and for the motor drive to generate power the control circuit which has a voltage drop by using the said control circuit unit power supply circuit unit built power to the motor the regulator unit, the power and the control circuit unit The brushless motor driving method, which comprises supplying to the serial control circuit unit. 2. The method of driving a brushless motor according to claim 1, wherein the switching power element group, the control circuit section, and the regulator section are formed in a single chip IC and are built in the brushless motor. The printed wiring board on which the stator winding, stator core, rotor position sensor, switching power element group, control circuit unit, power supply circuit unit for control circuit unit, and regulator unit are mounted is integrally molded with thermosetting resin. 3. The method of driving a brushless motor according to claim 1, wherein a stator is formed. 3. The method of driving a brushless motor according to claim 1, wherein the power supply circuit section for the control circuit section is constituted by a power transistor and a resistor and is built in the brushless motor.

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