Study of the reactive power control for a real UHVAC power transmission project

Abstract

SUMMARYThe reactive power compensation mode used for the present commercial ultra-high-voltage alternating current power transmission system could not entirely meet the requirements of reactive power balance. The reactive power interchange (RPI) between the ultra-high-voltage (1000 kV) power grid and the 500 kV power grid would impact on the reactive power control strategy.In this paper, an in-depth analysis of the relationship between the RPI and the voltage modulus ratio (VMR) of the sending side to the receiving end is executed. It is proved that the RPI could be expressed as a function of the VMR.An optimal minimized RPI (MRPI) control strategy that minimizes the RPI while satisfying the steady state over-voltage restriction is proposed. To solve the optimal problem, the immune genetic algorithm is used in this work. By practical calculation examples, the MRPI control strategy's feasibility and validity under various operation modes in East China Grid is validated.