Minimax Optimization for Capacitors Composited with Two Kinds of Series Reactance Rates

Abstract

For the reasonable series reactance rate in capacitor of substations, the full parametric harmonic circuit and model for 220 and 110 kV substations are established, which consists of transformer, load, short impedance and harmonic source, capacitors that two reactance rates are adopted. Moreover, the resonance objective function is proposed, which reflects the degree of resonance, such as, harmonic voltage amplification factor on load bus, etc. With the method of minimax optimization, the maximum values of objective function in all the power grid parameter space are minimized by changing reactance rate. The optimization results show that resonance is eliminated with the best effect by using a set capacitor with 12% series reactance rate and another groups of capacitors with 4.5%, and the result also reduces the loss and cost. At the same time, this conclusion is suitable for all 220 and 110 kV substation.