Power capacitor protector

Abstract

The invention relates to protective equipment of an electric power capacitor, in particular to a protector of an electronic type electric power capacitor. The invention is characterized in that a current transformer, and an electronic component are installed in a casing body; wherein, the electronic component comprises an electrical current signal detecting circuit, a power supply indication circuit, an overcharging control circuit, a severe overcharging and manual resetting control circuit, phase protecting control circuit, a driving output circuit and a power supply circuit, and other a plurality of circuits. The electrical current signal on the electric power capacitor is detected by the current transformer in a splitting phase, divided into four circuits and outputs to the power supply indication circuit, the overcharging control circuit, the severe overcharging and manual resetting control circuit and the phase protecting control circuit after being enlarged by an operational amplifier UIA and being detected, and then connected to the driving output circuit; the power supply circuit is divided into three voltage classes and connected with the inlet wire terminals and the grounding terminals of the power supplies of the four circuits. The invention has the advantages of complete protection performance, high precision and scientific control and rationalized self-returning and self-locking properties, and the invention is widely applied to the complete set of the reactive power compensation equipment.

Description

technical field [0001] The invention relates to power capacitor protection equipment, in particular to an electronic type power capacitor protector. Background technique [0002] Power capacitors are in a long-term loading state and are often impacted by overvoltage and overcurrent caused by various abnormal factors in the power grid. When the voltage and current in the system exceed the rated limit of the capacitor, the internal dielectric loss of the capacitor will increase, resulting in overheating. Accelerates insulation aging, reduces service life, and may cause dielectric breakdown in severe cases, causing a branch failure behavior to cause the entire network to trip, resulting in repeated failures. Therefore, certain protection measures must be taken for the power capacitors of each branch in the power factor compensation. However, for a long time, the protection of power capacitors has basically adopted the protection method of thermal relays. Thermal relays themsel...

AI Technical Summary

Problems solved by technology

But for a long time, the protection of power capacitors has basically adopted the protection method of thermal relays. The thermal relay itself is used for thermal overload protection of motors, and its inherent functional characteristics cannot realize special fault protection for power capacitors. With the development of electronic technology Progress, only by using the working principle of electronic circuits to design electronic power capacitor protectors can be closest to the actual protection needs of power capacitors

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