Motor driving device and method thereof

Abstract

Brake mode switching signal production means detects the number of revolutions per unit time of a rotor according to a change in a positional relationship between motor windings of a plurality of phases and the rotor so as to output first and second brake mode switching signals for selecting either a short brake mode or a reverse brake mode for braking the rotation of the rotor based on the number of revolutions. Control means outputs an energization control signal for controlling energization of the motor windings of a plurality of phases in response to the first and second brake mode switching signals. Thus, it is possible to reduce the braking noise and the stopping time.

Description

technical field [0001] The invention relates to a motor drive with a short-circuit brake and a reverse brake. Background technique [0002] As methods for stopping the motor, there are deceleration methods using a short-circuit brake and deceleration methods using a reverse brake. Moreover, the existing motor drive device has two modes: a short-circuit braking mode in which braking is performed by a short-circuit brake and a reverse braking mode in which braking is implemented by a reverse brake. deceleration and stop control. [0003] The motor deceleration method of the short-circuit braking mode adopts the method of forming a short-circuit circuit between the terminals of the 3-phase motor winding, and the motor deceleration method of the reverse braking mode adopts the method of supplying reverse current to the multi-phase motor winding. The current is driven in the reverse direction. [0004] Figure 9 It is a figure which shows the structure of the conventional moto...

AI Technical Summary

Problems solved by technology

When the short-circuit braking mode is used, the noise of the motor M1 will not be generated during braking, and because the braking force depends on the counter voltage, it is very effective at high-speed rotation, but the braking force of the brake also decreases as the rotational speed decreases. Therefore, it takes a long time to come to a complete stop

[0015] When the reverse braking mode is used, since the motor windings L1~L3 are driven in the opposite direction during deceleration, the braking force is stronger, but the noise during high-speed rotation caused by phase deviation is relatively high

In addition, high-precision reverse detection is difficult. When the moment when the energization control signal S8 of the opposite polarity is stopped lags, even after the motor M1 stops, it will still drive in the opposite direction for a period of time, resulting in rotation in the opposite direction.

After that, although the energization control signal generating device 70D stops energizing the three-phase motor windings L1 to L3, the motor M1 will continue to rotate due to inertia, which not only takes a long time until it stops completely, but also makes the stop position of the motor inaccurate.

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