Control circuit and method for controlling alternating current contactor by using direct current voltage

Abstract

The invention discloses a control circuit and method for controlling an alternating current contactor by using direct current voltage, and the control circuit comprises a power conversion distribution circuit which is used for converting alternating current into first direct current voltage and second direct current voltage and transmitting the first direct current voltage and the second direct current voltage to the input end of a coil of the alternating current contactor through a high-voltage direct current circuit and a low-voltage direct current circuit respectively; the low-voltage direct-current circuit comprises a voltage-stabilized power supply for controlling the second direct-current voltage to be output at a set voltage value, a voltage comparison circuit, a relay for receiving a control signal of the voltage comparison circuit and sending an execution instruction to the relay and a time-delay circuit; the first direct-current voltage is used for enabling the alternating-current contactor to generate pull-in action; and the second direct-current voltage is used for keeping a pull-in state after the alternating-current contactor is pulled in. The short-time pull-in voltage and the direct-current high voltage are provided for the alternating-current contactor, meanwhile, an auxiliary contact of the alternating-current contactor is not occupied, and the problem that the continuous pull-in current loss of the alternating-current contactor is large is solved.

Description

technical field [0001] The invention belongs to the technical field of power supplies, and in particular relates to a control circuit and a method for controlling an AC contactor by using a DC voltage. Background technique [0002] The AC contactor currently used is a component that acts as an electromagnetic coil. The AC voltage input generates a magnetic force to turn the switch on. When the AC input voltage disappears, the switch turns off, and the AC contactor has a large AC voltage loss: The magnetic field attracts the magnet to realize the purpose of switching on. In order to achieve the attraction of the magnet, a large AC magnetic field energy must be converted through the AC voltage. The AC current flowing through the contactor coil is relatively large, and the current specification of the AC contactor is higher. The greater the current, the greater the loss, and the greater the heat generated by the coil core: when the AC contactor is running, the AC voltage genera...

AI Technical Summary

Problems solved by technology

[0012] The object of the present invention is to provide a control circuit and method for controlling an AC contactor by using a DC voltage. Without changing the structure of the original contactor, a high DC voltage is used to provide a short-term pull-in voltage to the AC contactor. DC high voltage, while not occupying the auxiliary contact of the AC contactor, to solve the problem of large current loss of the AC contactor's continuous pull-in, and to achieve the purpose of energy saving

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