Low power consumption power capacitor fast discharge device

Abstract

The invention discloses a low power consumption power capacitor fast discharge device, and relates to the technical field of power grid alternating current power reactive compensation. The device comprises circuit units. Each circuit unit comprises a choke coil, a discharge resistor and an RC resistance-capacitance overvoltage absorber. Each choke coil is connected in parallel with a RC resistance-capacitance overvoltage absorber, and then is connected in series with a discharge resistor. Each RC resistance-capacitance overvoltage absorber comprises an absorption capacitor and an absorption resistor. Each absorption capacitor is connected in series with an absorption resistor, and then is connected in parallel with both ends of a choke coil. Three sets of circuit units are star-connected with A / B / C ports of a three-phase capacitor, wherein the neutral point is impending. Each absorption capacitor uses a ceramic capacitor with the rated voltage of 630V, and the capacity is 0.1uF. Each absorption resistor uses a carbon resistor with the powder of 1W. Each choke coil uses an EI type single winding transformer coil, and the input rated voltage is AC 250V. The device provided by the invention has the advantages of small running power consumption, stable operation without maintenance, low cost and short discharge time, and each set is less than 15 yuan.

Description

technical field [0001] The invention relates to the technical field of reactive power compensation for grid AC power, in particular to a power capacitor with a voltage level below 1000V, which is suitable for low-power consumption in reactive power compensation equipment such as public transformers, private line customers, substations, and power stations. Capacitor quick discharge device. Background technique [0002] High and low voltage AC power capacitors are not allowed to be switched on with residual charge; otherwise, at the moment of switching on, the input potential of the power grid and the residual potential of the capacitor may be reversed, and a large voltage will be generated when the potential difference is large. Current shock, in addition to causing switch tripping, overcurrent damage to the knife switch, and capacitor explosion, sharp pulses will also interfere with the normal operation of control equipment, and even cause accidents. Therefore, "DL / T1417-20...

AI Technical Summary

Problems solved by technology

Therefore, the compromise method of many capacitor manufacturers is to use a 200K discharge resistor, so that the discharge time of a small-capacity capacitor is acceptable, but when the capacitor capacity is large, the discharge time is still too long; according to the measurement, the capacitor of the existing compensation device The average action delay of the group is 40 seconds. When the reactive power of the power customer load fluctuates frequently, the compensation device cannot track the compensation in real time because it has to wait for the discharge of the capacitor bank to complete, resulting in over-compensation and under-compensation. Therefore, the market urgently needs a low-cost , high stability, simple circuit and maintenance-free fast discharge device for power capacitors

Images