Star-shaped and triangular wiring mode control device for motor

Abstract

The invention relates to a star-shaped and triangular wiring mode control device for a motor. The device comprises a first alternating-current contactor and a second alternating-current contactor, wherein the first alternating-current contactor and the second alternating-current contactor are used for converting the winding wiring of the motor. A current transformer BK1 is arranged in the current loop of the motor. The output signal of the current transformer is sent to the input end of a comparison unit. The output signal of the current transformer is compared with a set value in the comparison unit. The output end of the comparison unit is connected with the input end of a power amplifying unit. The power amplifying unit is used for driving a relay. According to the size of the output signal of the current transformer, the relay controls the alternating-current contactors to enable the winding mode of the motor to be directly converted between the triangular wiring mode and the star-shaped wiring mode, so that the electric energy consumption of the motor can be effectively reduced. The electricity can be saved by more than 10%. A delay circuit is arranged in the comparison unit, so that the frequent switching between the triangular wiring mode and the star-shaped wiring mode of the motor due to the existence of interference signals can be prevented. Meanwhile, the motor can be started in the triangular wiring mode.

Description

technical field [0001] The invention relates to a motor star-delta connection mode control device. Background technique [0002] The load of the motor of the metal cutting machine tool is related to the cutting amount of each batch of workpieces. For example, there are differences between rough machining and finishing machining, and the size of the workpiece. If the load is small, the phenomenon of large horses and small carts will appear, which wastes electric energy. Contents of the invention [0003] The technical problem to be solved by the present invention is to provide a motor star-delta connection mode control device. When the motor is heavily loaded, the motor operates in delta connection mode. When the motor is lightly loaded, the motor operates in star connection mode to reduce power consumption. [0004] The technical solution of the present invention to solve the technical problem is a motor star-delta connection mode control device, which includes a first AC...

AI Technical Summary

Problems solved by technology

[0002] The load of the motor of the metal cutting machine tool is related to the cutting amount of each batch of workpieces. For example, there are differences between rough machining and finishing machining, and the size of the workpiece. If the load is small, the phenomenon of large horses and small carts will occur, which wastes electric energy.

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