Reactive compensation discharge device

Abstract

The invention discloses a reactive compensation discharge device, which is characterized in that a primary-side three-phase winding of a three-phase transformer is in Delta-type connection or Y-shaped connection; the primary-side three-phase input end of the three-phase transformer is connected with the three-phase input end of a reactive compensation capacitor group in parallel; a secondary-side winding of the three-phase transformer is set to an open-delta connection mode, and impedance is accessed to the open-delta shape; and after a circuit breaker removes the reactive compensation capacitor group from the system, the interphase equivalent impedance and the reactive compensation interphone capacitance of the reactive compensation discharge device in the reactive compensation capacitor group form a discharging circuit for discharging. After the circuit breaker powers off the reactive compensation capacitor group, the reactive compensation discharge device discharges rapidly to the reactive compensation capacitor group, so that the voltage pressure of an on-off cut is smaller than the insulation intensity, and therefore the reignition of the reactive compensation capacitor group which is powered off by the circuit breaker is eliminated.

Description

technical field [0001] The invention relates to a reactive power compensation device for electric power. Background technique [0002] 1. Re-ignition of reactive power compensation vacuum circuit breaker is a worldwide problem [0003] Reactive power compensation cannot be overcompensated, so with the change of system operation mode, frequent switching of reactive power compensation capacitors, and the switching circuit breaker of reactive power compensation capacitors require no restrike. Vacuum circuit breakers have the advantages of small size, good arc extinguishing performance, long life, small maintenance, safe use, etc., and are widely used in medium voltage systems and power distribution networks. Especially because of its characteristics of being suitable for frequent operation, vacuum circuit breakers are basically used to switch reactive power compensation capacitor banks in parallel reactive power compensation capacitor compensation devices. [0004] In the pro...

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Problems solved by technology

[0005] 2. Technical improvements in mechanical structure and manufacturing process have little effect in reducing the reburning rate

[0008] ① Thyristor current zero-crossing and equipotential switching are limited by the development of power electronics. It is difficult to apply in practice, the cost is very high, the cost of maintenance is extremely high, and the reliability is poor. Currently, it can only be applied in low-voltage systems.

[0009] ② Vacuum circuit breaker current zero-crossing and equipotential switching (phase-controlled vacuum circuit breaker), due to the cost of thyristor current zero-crossing and equipotential switching, high maintenance costs, and poor reliability, some researchers use single-phase vacuum circuit breakers , the opening and closing time of each single-phase vacuum circuit breaker is controlled by a microcomputer, which is theoretically feasible and difficult to realize in practice, because the operating time of the vacuum circuit breaker’s operating mechanism is a large discrete time value interval, and the current cannot cross zero. And equipotential switching, still can not really reduce the re-ignition rate, this method has not yet been practically applied

That is to say, technical improvements in mechanical structure and manufacturing process have become powerless, with little effect, and cannot prevent the vacuum circuit breaker from restarting.

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