JP2003219684A - Brushless motor driving device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a starter device for a brushless motor that makes the motor start smoothly. <P>SOLUTION: In a brushless motor driving device, a combination of stator windings, which are conducted first when the motor is started, is configured to change every time the motor is started. Because the motor is controlled in such a way as not to repeat the same start failure, it can be started smoothly. Also, the repetition of the same start failure can be prevented by avoiding starting in the same conductor pattern with the one that ever caused a failure. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention detects a change in an induced voltage which occurs in a stator winding which has a plurality of permanent magnets and which is not energized by the rotation of a rotor, and which energizes based on this detection signal. The present invention relates to a drive device for a brushless motor in which a subsidiary winding is sequentially switched.

[0002]

2. Description of the Related Art As a conventional technique for a motor drive device,
There is one described in JP-A-7-147795. The brushless motor starting method described in this publication is started by a synchronous operation in which the energization of the stator winding is sequentially switched, the energization cycle is gradually increased, and the rotor speed is increased to a predetermined speed. It was to switch to position detection operation by induced voltage.

[0003]

In the brushless motor starting method according to the above publication, since the rotor position is unknown at the time of starting and is not always the same, energization is performed from a predetermined assembly of the stator windings. If it starts, the assembly of the stator winding to start energization is not always appropriate, the rotor may rotate in reverse, and depending on the load torque state, it may not be possible to bring it into synchronous operation and the motor may not start. There is. In addition, when starting fails and restarting is performed, since energization is started from the same combination of stator windings as when starting fails, similar starting failures may occur.

The present invention provides a starting device for a brushless motor, which makes it possible to start the motor well.

[0005]

In order to solve the above problems, a rotor having permanent magnets having a plurality of poles and a plurality of stator windings arranged to give a rotating magnetic field to the rotor when energized are provided. Of the plurality of stator windings, a rotating magnetic field is obtained by energizing some of the stator windings, and a change in induced voltage caused by rotation of the rotor is generated in the non-energized stator windings. In a brushless motor driving device configured to detect and sequentially switch the energized stator windings based on this detection signal, the combination of the stator windings that are energized first when the motor is started is changed every time the starting is performed. It is configured as follows.

Further, it has a rotor having permanent magnets of a plurality of poles and a plurality of stator windings arranged to give a rotating magnetic field to the rotor when energized. Of the stator winding to obtain a rotating magnetic field, detect a change in the induced voltage caused by the rotation of the rotor in the stator winding that is not conducting, and energize based on this detection signal. In a brushless motor drive device configured to sequentially switch windings, when the motor cannot start normally and restarts, the stator windings other than the combination of stator windings that could not start normally The first energization is started from the combination.

Furthermore, a rotor having permanent magnets of a plurality of poles and a plurality of stator windings arranged to give a rotating magnetic field to the rotor when energized are provided. A fixed magnetic field is obtained by energizing some of the stator windings to obtain a rotating magnetic field, detecting changes in the induced voltage caused by the rotation of the rotor in the non-energizing stator windings, and based on this detection signal. In a drive device of a brushless motor configured to sequentially switch the child windings, when the motor cannot be normally started and restarted, the first combination from the stator windings that has been normally started many times is used. It is configured to start energization.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a first embodiment (corresponding to claim 1) of the present invention will be described with reference to the drawings.

FIG. 1 shows a control block diagram of an embodiment of the present invention. The AC power supply 1 is connected to the brushless motor 5 through a semiconductor switching element 4 which is rectified by a rectifying circuit 2 and which is three-phase bridge-connected.

The microprocessor 7 includes a position detection circuit 6
In step 1, a drive signal is given to the drive circuit to sequentially switch the energized stator windings based on the rotor position detection signal obtained by detecting the change in the induced voltage from each motor terminal.

When starting the brushless motor, as shown in FIG.
The combination of the stator windings is stored in the microprocessor in advance as an energization pattern as shown in (1), energization is started from the energization pattern 1, the energization patterns are sequentially switched, and the rotor in the stopped state is rotated.

Here, the energization pattern to be initially energized at the time of starting is not from the same energizing pattern, for example, energizing pattern 1 at the first starting and energizing pattern 2 at the next starting.
Every time the engine is started, the energization pattern to be energized first is changed.

The pattern to be energized first may be selected in order from pattern 1 to pattern 6, or a method of selecting a pattern as shown in FIG. 3 or a method of selecting randomly. When the energization is started from the energization pattern 1 and the start fails, and the engine is restarted, the same energization pattern l
Therefore, the energization is started from another energization pattern (for example, the energization pattern 2), and the same starting failure is prevented from being repeated.

Next, a second embodiment (corresponding to claim 2) will be described. Similar to the embodiment of claim 1, the energization pattern which is energized first when the motor is started is changed every time it is started. If the start fails, the first energization pattern when the start fails is stored in the memory in the microprocessor, and the start is not performed from the same energization pattern as when the start fails. An example will be described in which the first energization pattern is selected in order from the energization pattern 1 to the energization pattern 6 in order. When starting for the first time, energization is started from energization pattern 1. When starting next, energization is started from energization pattern 2, and thereafter, pattern 1 to pattern 6 are sequentially selected each time it is started. Here, if the energization is started from the energization pattern 1 and the start fails, the patterns 2 to 6 are sequentially selected so as not to start the energization from the energization pattern 1. That is, the start of energization starting from the same energization pattern as when the start fails is prevented from being repeated, and the same failure of start is prevented from being repeated. In addition, when the number of times of failure in starting is large, the number of times of failure and the energization start pattern at that time are stored in the memory in the microprocessor, and energization is started from the energization pattern in which the number of times of starting failure is small, and the probability of starting failure is calculated. It can be lowered. As a result, a good start can be achieved.

[0015]

As described above, according to the brushless motor drive device of the present invention, when the energization is started from a certain energization pattern and the starting fails and the restart is performed, the energization pattern is different from the same energization pattern. The energization is started from this energization pattern, and it is possible to prevent the same starting failure from being repeated.

According to the second aspect of the present invention, it is possible to prevent the same starting failure from being repeated by not starting the energization starting from the same energization pattern as when the starting fails.

[Brief description of drawings]

FIG. 1 is a control block diagram showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an energization pattern of a stator winding that energizes.

FIG. 3 is a diagram illustrating a relationship between the number of times of starting and an example of an energization pattern in which electricity is applied first.

[Explanation of symbols]

1 AC power supply 2 rectifier circuit 3 smoothing capacitors 4 Semiconductor switching element 5 3-phase DC brushless motor 6 Position detection circuit 7 microprocessors 8 drive circuit

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hideaki Kato             2-5-3 Keihan Hondori, Moriguchi City, Osaka Prefecture             Within Yo Denki Co., Ltd. (72) Inventor Tetsuo Nomoto             2-5-3 Keihan Hondori, Moriguchi City, Osaka Prefecture             Within Yo Denki Co., Ltd. (72) Inventor Arata Sekino             2-5-3 Keihan Hondori, Moriguchi City, Osaka Prefecture             Within Yo Denki Co., Ltd. F term (reference) 5H560 BB04 BB12 DA13 EB01 HA08                       SS07

Claims (2)

[Claims] 1. A rotor having a plurality of poles of permanent magnets and a plurality of stator windings arranged to give a rotating magnetic field to the rotor when energized. Of the stator winding to obtain a rotating magnetic field, detect a change in the induced voltage caused by the rotation of the rotor in the stator winding that is not conducting, and energize based on this detection signal. A brushless motor drive device in which windings are sequentially switched, wherein a combination of stator windings that are initially energized when the motor is started is changed every time the motor is started. 2. A rotor having a plurality of permanent magnets having a plurality of poles, and a plurality of stator windings arranged to give a rotating magnetic field to the rotor when energized. Of the stator winding to obtain a rotating magnetic field, detect a change in the induced voltage caused by the rotation of the rotor in the stator winding that is not conducting, and energize based on this detection signal. In a brushless motor drive device configured to sequentially switch windings, when the motor cannot start normally and restarts, the stator windings other than the combination of stator windings that could not start normally A brushless motor drive device characterized in that the first energization is started from the combination.