Electromagnet control device

Abstract

The new electromagnet control device with oscillating circuit includes rectification circuit, reduction voltage filtering voltage stabilizing circuit, electromagnet control circuit, electromagnet, start circuit, divider circuit. Input of the rectification circuit is connected to mains supply, and output of the circuit provides operational power supply for each circuit. Input of the start circuit is connected to output of the reduction voltage filtering voltage-stabilizing circuit. Electromagnet control circuit controls electromagnet to carry out operation of attracting and releasing. Output of the divider circuit is connected to output of the start circuit. Characters are that an oscillating circuit is connected between output of the start circuit and input of the electromagnet control circuit. Advantages are: simple structure and high capability for anti interference.

Description

technical field [0001] The invention relates to a control device of a low-voltage circuit breaker, in particular to an electromagnet control device in the circuit breaker. Background technique [0002] Typically, this electromagnet control device can be applied to circuit breaker accessories, such as shunt release and closing electromagnet. Of course, this electromagnet control device is not limited to the above occasions, and can be used to control electromagnetic All occasions for iron attraction and release. [0003] At present, the control circuit of the electromagnet control device in the common circuit breaker is as follows: figure 1 shown. The grid voltage is rectified by diodes D1', D2', D3', and D4' to output DC voltage U1', U1' is divided by resistors R1' and R2', and then passed through diode D5', capacitor C1', Zener diode D6', The resistor R3' smooths and filters the output voltage U2', and U2' charges the capacitor C2'. During the charging process, a voltage...

AI Technical Summary

Problems solved by technology

[0004] Due to the high input impedance of this circuit, the interference of other factors to this circuit cannot be well prevented, such as electrostatic interference, electromagnetic field interference, etc. These interferences can make the capacitor C2' precharge, so that when the normal closing and opening, due to no longer Charge the capacitor C2', so that the field effect transistor VT1' cannot be turned on, and the electromagnet does not pull in

[0005] In the Chinese Patent No. 93236467.5 titled "Power Saving Contactor", the electromagnet control circuit T s , J and CRT issue a conduction command when the power is off to achieve the purpose of releasing the electromagnetic system, but they cannot prevent static electricity and electromagnetic field interference. When interference occurs, the electromagnet cannot be normally attracted, and the action of the electromagnetic system is unreliable.

[0007] In the Chinese Patent No. 90215388.9 titled "Dynamic Electromagnetic Drive with High Efficiency and Energy Saving at Low Temperature", the pulse width output by the oscillation circuit of the electromagnet control device can only be set in advance and cannot be adjusted dynamically. When the power supply voltage is too low, it may be caused by the coil The current is too small to keep the electromagnet in the state of attraction; when the power supply voltage is too high, the temperature of the electromagnetic coil may be too high due to the excessive coil current, or even burn out, which reduces the operating reliability of the electromagnetic coil

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