Synthetic apparatus of anti-flashover and protection for low-voltage three phase asynchronous motor

Abstract

Disclosed is an anti-interference and comprehensive protection device for a low voltage three-phase asynchronous motor, which can realize the restarting of the low voltage three-phase asynchronous motor when the motor is shut down by the fluctuation of the low voltage power network, thereby solves the problem that the product line of industry manufacture enterprise can be shut down abnormally by the power-shaking. The invention is composed of the follows: 1, a processor, 2, a clock chip, 3, a battery, 4, a voltage comparator circuit, 5, a monitor circuit of a contactor, 6, a control circuit of a relay 7, a second control loop, 8, a switching power supply, and 9, a wire connection terminal. The invention can restart the motor when the power is switched on after the motor is shut down due to the power-shaking of the power network, can distinguish two different failures of power-shaking and long-time under-voltage, and can judge whether the motor is working before power-shaking. The anti-interference and comprehensive protection device of the invention has the advantages of high setting accuracy, good repeatability and accurate action time, and does not need external equipment to provide high power backup power supply.

Description

technical field

[0001] The invention is applied in the field of low-voltage three-phase asynchronous motor control and protection, and can realize the restart of the low-voltage three-phase asynchronous motor when it is stopped due to the fluctuation of the low-voltage line grid, thereby solving the problem of abnormal shutdown of the production line caused by the shaking of electricity in industrial production enterprises , belonging to the field of electrical automation control. Background technique

[0002] "Shaking electricity" is a phenomenon in which the voltage fluctuates greatly and the power supply disappears instantaneously caused by the short circuit of the line or electrical equipment in the factory area, but it is restored in a short time through the function of automatic reclosing and backup power self-input device. If the equipment and system have poor ability to resist "shock electricity", it will bring undue loss to production. In general chemical and petro...

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