Improvement of reactance compensator using variable active-passive reactance with output filter

Abstract

A reactance circuit affects the operation in a power circuit. For example, the transmission power of the AC power line depends on the interconnecting line impedance between the two places. A new compensating method of inductance using variable active-passive reactance (VAPAR) has been proposed to control the existing reactance of a power circuit. In this paper, first, the authors propose an improved control method of the VAPAR to suppress resonances of the output voltage and current caused by the output filter using a state feedback method. The produced virtual impedance becomes the desired virtual inductance up to the limited frequency. Then, the frequency characteristics of the virtual inductance generated by the VAPAR is analyzed to clarify the relationship between the frequency characteristics of the virtual inductance and transient response through simulations. From these considerations, the design method of the required characteristics are discussed.