Research on the failure mechanism of closing resistance under impulse current

As a key component of the tank circuit breaker, the closing resistance mainly inhibits the closing inrush current of the circuit breaker in the process of opening and closing, and accidents occur frequently during operation. Based on this, the thermal and mechanical simulation model of the closing resistance is established to analysis the failure of the impact current on the closing resistance; Firstly, the temperature rise process under different impact accurent with the amplitudes of 1.12kA, 1.68kA and 2.24kA respectively. Then and the stress distribution is also calculated. The results show that Excessive impact current causes faster temperature rise, which can lead to thermal damage of the closing resistor. While the impulse current reaches about 1.76kA, the average stress of the closing resistance reaches the material limited stress of the closing resistance and the maximum stress is on the outer edge, so it turns out the early destruction occurs this place. These conclusions can guide the analysis of the failure mechanism of the closing resistor.