Control of variable active-passive reactance (VAPAR) and negative inductance

The concept of the variable active-passive reactance (VAPAR) which behaves like a two-terminal reactive element, and the produced active reactance works as a passive reactive component, including in transient state. In this paper, the authors propose the equivalent resistance control method for the capacitor DC voltage regulation when a capacitor is used as an energy storage element of the VAPAR. The series equivalent resistance is added to the produced virtual inductance, and the capacitor voltage is controlled by changing the series equivalent resistance. The proposed scheme is verified by simulations and experiments. The realization of the negative inductance is then proposed. Through simulations and experiments, it is verified that the VAPAR can generate negative inductance, which may be applied to FACTS. The effects of negative inductance are compared with that of series capacitance used in power systems