Three-phase asynchronous motor starting device and starting method thereof

Abstract

The invention relates to a three-phase asynchronous motor starting device and a starting method thereof and belongs to the motor technical field. The invention aims to improve the starting performanceof a motor. The device comprises three-phase windings, a three-phase power source switch and a change-over switch; each phase of winding comprises a first electromagnetic switch, a second electromagnetic switch, a third electromagnetic switch, a first coil group and a second coil group, wherein the first coil group and the second coil group are connected in series through the first electromagnetic switch, and the first coil group and the second coil group are connected in parallel through the second electromagnetic switch and the third electromagnetic switch; and when the motor is started, the change-over switch cooperates with the electromagnetic switches, so that the two coil groups in each phase winding are controlled to be connected in series with each other at first and then connected in parallel with each other. With the device and the method provided by the invention adopted, the starting current of the motor and the impact of the starting current on a power grid can be decreased, an impact torque is small, and the secondary impact is also small.

Description

technical field [0001] The invention relates to motor technology, in particular to the technology of a three-phase asynchronous motor starting device and a starting method thereof. Background technique [0002] Three-phase cage-type asynchronous motors have the defects of large starting current and starting torque, so the existing three-phase cage-type asynchronous motors generally use stator winding series resistors (or series reactors), transformer step-down, and star-delta starting And other methods to reduce the starting current and starting torque, so as to avoid the large impact on the power grid and equipment when the motor starts. [0003] Stator winding series resistance starting requires a special starting resistor, which consumes a certain amount of active power during the starting process, while the starting of the stator winding series reactor requires a special starting reactor, which consumes a certain amount of active power during the starting process. The p...

AI Technical Summary

Problems solved by technology

Electrical angle, so the current in the winding is usually reversed, interrupted, there is an arc at the terminal, and there is a secondary impact of current and torque

Images