Static voltage sharing technology of multi‐break mechanical switch for hybrid HVDC breaker

The hybrid high‐voltage direct current (HVDC) breaker combines mechanical and power electronics switching that enables it to interrupt power flows within a few milliseconds. Mechanical switch is a key component of hybrid HVDC breaker and has a number of serially connected interrupter units which ideally would divide the voltage equally. The static voltage distribution characteristics and voltage sharing design of a multi‐break mechanical switch were discussed in this study. A finite‐element model was developed to study the static voltage distribution characteristics and capacitance parameters of multi‐break mechanical switch (which actually consists of resistance and capacitance parameters under direct current) as a preliminary study. Comparisons were made under the simulation of vertical and U‐shaped arrangement forms. The results indicate that the static voltage distribution of the high‐voltage terminal is at least more than 65%, whereas the severe non‐uniform voltage distribution can be well improved by means of the method proposed in this study.