The influence of UHV hybrid reactive compensation and its stray capacitances on the interrupting characteristics of circuit breaker at out-of-phase fault

Abstract

The hybrid reactive compensation is expected to be applied in UHV transmission lines in the future, and its mutual influence with power grid is urgent to be studied. Considering the influence of the ground stray capacitance of the series compensation devices, the disposal scheme, and the installation position et al., the influence to the out-of-phase fault by the hybrid reactive compensation was computational analyzed. And the out-of-phase fault interrupting current amplitude, the transient recovery voltage(TRV) and the rate of rise of recovery voltage(RRRV) theoretical derivatived in the paper when considered the impact of the ground stray capacitance. The results show that with the increase of the stray capacitance value, TRV first peak value has linear downward trend, and has same impact on the RRRV and out-of-phase fault interrupting current amplitude. The controlled shunt reactor near the circuit breaker can reduce the severity of the out-of-phase fault compared with the series compensation devices close to it. TRV first peak value, its RRRV and the out-of-phase fault interrupting current can be decreased by increasing the distance between the controlled shunt reactor and the end of the line.