Study on Transient Electric Field Distribution of 40.5 kV Switchgear Vacuum Circuit Breaker Cut-Off Reactor

The high frequency electromagnetic wave generated by the interruption of the circuit breaker of the high voltage switchgear may interfere with the performance of the intelligent sensor and even cause damage, endangering the safe and reliable operation of the switchgear. Taking KYN61-40.5 high voltage switchgear as an example, the 3D finite element simulation model of high voltage switchgear was established and its accuracy was verified through the test. Taking cutting off reactor overvoltage in 35 kV system as the example, the distribution of high frequency electric field in typical system of high voltage switchgear is studied. The simulation results show that the maximum internal electric field intensity can reach 2.46 kV/mm during the interruption process. The maximum electric field intensity is located at the top of the breaker truck, the top of the breaker room partition, and near the partition of the bus room and cable room. The research results can provide a reference for the installation of intelligent sensors in switchgear and its electromagnetic compatibility designs.