Synchronous Motor Sealing Star Control System and Method

Abstract

The invention provides a synchronous motor star sealing control system and method. The star sealing control system includes a master controller, a drive logical unit, a star sealing logical unit and a motor drive unit, wherein the master controller is used for generating a motor drive pulse and a star sealing signal; the drive logical unit is used for generating an upper bridge arm drive pulse and a lower bridge arm control pulse according to the motor drive pulse; the star sealing logical unit is used for generating a lower bridge arm drive pulse according to the star sealing signal and the lower bridge arm control pulse; and the motor drive unit is used for controlling an upper bridge arm and a lower bridge arm of a frequency converter according to the upper bridge arm drive pulse and the lower bridge arm drive pulse to realize motor driving or star sealing. Through a combination of the motor drive pulse and the star sealing signal, the star sealing control system realizes star sealing control of a synchronous motor, thus star sealing of the synchronous motor can be realized without a star sealing contactor, and a star sealing delay of the star sealing contactor can be effectively avoided.

Description

technical field [0001] The invention relates to the field of motor control, and more specifically, relates to a synchronous motor star sealing control system and method. Background technique [0002] In the permanent magnet synchronous traction machine, by connecting the lead wires of the three-phase windings with wires or series resistors in a star shape, an independent electrical circuit is formed inside the motor, which induces an induced current in the armature winding circuit and at the same time induces current in the permanent magnet of the motor. Under the action of the magnetic field, the braking electromagnetic torque is generated, so as to prevent the synchronous traction machine from losing power and causing the elevator to slide or run away. This technology is called "Fengxing" in the industry. Since the application of the permanent magnet synchronous traction machine on the elevator, its "sealed star" braking function has been promoted and applied as an advanta...

AI Technical Summary

Problems solved by technology

When the inverter needs to output, and the star contactor is still short-circuiting the three-phase winding of the synchronous motor, it will cause the inverter to be short-circuited and over-current, thus damaging the inverter

[0006] (2) When the frequency converter stops due to failure, the synchronous motor still has a high speed due to inertia, and the star contactor has short-circuited the three-phase winding of the synchronous motor at this time, so there will be a large short-circuit current in the synchronous motor. The impact caused by the synchronous motor will affect the life of the motor. At the same time, the Fengxing contactor also has a certain capacity, and the impact current will also cause irreparable failures to the Fengxing contactor.

[0007] (3) Under different rated load conditions, the capacity of the star-sealing contactor required is also different, and as the capacity increases, the cost of the star-sealing contactor will increase, and under certain conditions it may not be possible to choose a suitable star-sealing contactor star contactor

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