JP2006314184A - Motor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that ring current by voltage induced by winding flows by motor rotation and efficiency is deteriorated when DC resistance and inductance are unbalanced when winding is connected in parallel, if a plurality of windings are given to respective phases of statuses of a brushless motor. <P>SOLUTION: One driving device is arranged for one wiring or winding of each phase is divided into several groups, and one driving device is prepared at every group and power is supplied. Thus, output voltage and current of the driving device become small compared to a case when all wirings are connected in series and parallel at every phase. Consequently, the motor of large capacity can be driven by a system. When one driving output is prepared for one wiring, current unbalance, voltage unbalance and ring current due to series/parallel connection of winding do not occur. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a brushless motor, a drive device, and a control device that have a plurality of windings in each phase and can drive these with a plurality of drive outputs.

  When there are multiple windings for each phase of the brushless motor stator, connect the multiple windings of each phase in parallel, in series or in series, and connect them so that each phase can be regarded as one winding. In addition, supplying power from one output of a driving device has been widely performed.

  In the prior art, for example, in the case of parallel connection, since a plurality of windings connected in parallel are driven by one output of the driving device, the driving output multiplies the current required for one winding by the number of parallel circuits. Current must be supplied.

  In the case of series connection, the drive output must be supplied by multiplying the voltage required by one winding by the number of series circuits.

  The output part of the drive device is composed of semiconductor elements such as IGBTs and power MOS FETs, for example. However, there are limits to the maximum current and voltage rating of semiconductor elements that are generally supplied by semiconductor manufacturers, and as the output of motors increases, A situation occurs where the voltage and current handled exceed the limits of the device voltage and current rating.

  In order to cope with this situation, a plurality of semiconductor elements are connected in parallel when the current rating is insufficient, or a plurality of semiconductor elements are connected in series when the voltage rating is insufficient. .

  However, there may be a problem of unbalance of currents flowing through the elements when connected in parallel, or unbalance between voltages applied to the elements when connected in series.

  Another problem is that some windings are overheated due to current imbalance or voltage imbalance of each winding due to different DC resistance, inductance, etc. of the windings connected in parallel or in series. Will occur.

  If the DC resistance and the inductance are unbalanced when the windings are connected in parallel, a ring current flows due to the voltage induced in the windings due to the motor rotation, deteriorating the efficiency.

  In the present invention, in a three-phase or multi-phase brushless motor having a plurality of windings per phase, the same number of driving outputs as the number of windings can be obtained without connecting the plurality of windings in each phase in advance. Prepare or divide the windings of each phase into several groups and connect them to each other in advance, and prepare the same number of drive outputs as the number of groups to supply power.

  Therefore, since the output voltage and current of the drive output can be smaller than in the case of the prior art in which all windings are connected to each other for each phase, the capacity of the present invention is larger. The motor can be driven.

  Further, when one drive output is prepared for one winding, the problem of current imbalance and voltage imbalance due to the series-parallel connection of the windings and the ring current do not occur.

  Since the present invention is configured as described above, the following effects can be obtained.

  According to the present invention, the current flowing through one winding of the motor or the voltage to be applied can be reduced, the output circuit of the drive device can be easily manufactured, and a motor with higher output can be driven.

  Further, no ring current that may occur when the windings are connected in parallel is not generated, and the efficiency is not lowered.

  As the semiconductor element used for the output circuit, one having a standard rating that can be expected to be low-cost due to the mass production effect can be used.

  Since the control signal is a common signal even if the number of drive devices increases, the types of signals that the control device should output do not increase.

An embodiment of the present invention will be described with reference to FIG.
The motor 5 is a three-phase brushless motor of U, V, and W, and each phase includes three windings. The first to third windings of each phase have the same number of turns and winding diameter. Each phase winding is 3-phase Y-connected.

The driving devices 1, 2, and 3 are three-phase bridge inverters having three-phase outputs of U, V, and W.
S1 to S6 of the drive device 1 are semiconductor switch elements, which convert DC power supplied from the DC power supply device 6 through the power supply input terminals + and − into three-phase AC power, and 1 is supplied to windings (U1, V1, W1). The diodes D <b> 1 to D <b> 6 are turned on by the counter electromotive voltage generated by the motor winding, and regenerate energy stored in the winding inductance to the DC power supply device 6.

  Opening and closing control of the switches S1 to S6 in the control devices 1, 2, and 3 is performed by the control device 4. The control device 4 controls opening and closing of the switches S1 to S6 in each control device so that the outputs of the same phase of the drive devices 1, 2, and 3 are the same. The three-phase outputs U, V, and W have a phase difference of 120 ° from each other, and the outputs U, V, and W of each driving device are controlled to have the same phase and the same amplitude. For this control, conventional techniques such as “3-phase 120 ° energization rectangular wave drive” and “3-phase sine wave drive” described in Document 1 can be applied as they are.

  The driving devices 2 and 3 have the same circuit configuration as the driving device 1, and the three-phase outputs of U, V, and W are the second and third windings (U 2, V 2, W 2) of the three-phase windings of the motor 5, respectively. And U3, V3, W3).

Although one DC power supply device 6 is installed in common for the three drive devices 1, 2, and 3, a total of three DC power supply devices can be installed for each of the drive devices 1, 2, and 3.
As described above, electric power having the same phase and the same amplitude is supplied to the first to third three windings of each phase of the motor 5. As a result, compared with the case where the first to third windings are connected in parallel and driven with one output, the current per output is 1/3, and the current rating of the element used in the output circuit of the driving device is also It can be 1/3. Furthermore, since the windings are not connected in parallel, the aforementioned ring current is not generated.

Reference 1

“Motor Technology Practical Handbook (ISBN4-526-04715-5)” (March 23, 2001, Nikkan Kogyo Shimbun), Chapter 3, Section 3.2.2.

  The present invention can be suitably used not only for a motor that converts an AC power source into a DC power source and uses this as a power source, but also for a low-voltage, high-current motor such as for an electric vehicle that uses a storage battery as a power source.

1 is a motor device according to a first embodiment of the present invention. This is a conventional motor device.

Explanation of symbols

1-3: Drive devices D1-D6: Diodes S1-S6: Semiconductor switch element 4: Control device 5: Motors U1-U3: U-phase windings V1-V3: V-phase windings W1-W3: W-phase windings 6 : DC power supply

Claims (2)

In a three-phase or multi-phase brushless motor having a plurality of windings per phase, the number of drive outputs for supplying power to the windings is controlled, and the drive output phase and amplitude are controlled. A motor device characterized by comprising a control device. In the motor device, each of a plurality of drive outputs drives a plurality of windings connected in parallel or in series or series-parallel of each phase of the motor, and there are a plurality of drive outputs per phase of the motor. A motor device characterized.

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