Research and Application of Key Technologies for EHV Intelligent Series Compensation Control and Protection System

The key Because NOKIAN type series compensation control and protection system fails to ensure a stable power grid, intelligent reconstruction of the original system by using domestic equipment was reconstructed in order to abide by the principles of safety, reliability and advance. A current system with high anti-interference performance, high sampling rate and closed-loop control energy supply was studied. An IEC61850-based intelligent spark gap trigger system was developed which was time delayed and reduced as a whole. A double DSP board was applied in series compensation protection for the first time; the sampling data for starting and protecting the DSP board were collected from ADC sampling circuits respectively which are different from ECT; and the operation of series compensation protection is highly reliable. Accurate calculation of capacitor voltage was performed in case of line failure by using capacitor voltage algorithm based on dynamic capacitor current break variable integration to ensure the reliability of spark gas operation. A new type of intelligent test device was provided to handle the logic calibration of optical circuits and smart devices. The reconstructed intelligent series compensation control and protection system operated reliably in an extra-high voltage manual grounding short-circuit test and survived outside and inside failures in actual operation; and the series compensation operation was sensitive and correct in logic. The study results have been widely applied in the power grids in Beijing, Tianjin and Hebei, which increases the amount of transmitted energy and provides technical support for ensuring safe and reliable operation of power grids.