Time-optimal control of power systems requiring multiple switchings of series capacitors

Time-optimal control of switchable series or shunt capacitors requiring only a single switching has been proposed for damping power system swings resulting from large disturbances. This strategy is useful for a switchable series capacitor with a high compensation rating relative to the transmission system. In this paper, the general case of time-optimal control of series capacitors requiring multiple switchings is investigated. The strategy is applicable to a switchable series capacitor with a low compensation rating relative to the transmission system. It is illustrated for a single-machine infinite-bus system and an interconnected system. Suboptimal capacitor-switching control schemes are also investigated.