Variable inductors, which consist of a magnetic core and primary dc and secondary ac winding, can control the effective inductance of the secondary ac winding with primary dc current. Hence, they can be applied to electric power systems to compensate for reactive power. We proposed a three-phase laminated-core variable inductor in a previous paper, and demonstrated that its weight was reduced by more than 30% as compared with the conventional one. However, simulation including a control system is required to apply a variable inductor as a reactive power compensator. We therefore propose a method of calculating the characteristics of a three-phase laminated-core variable inductor using MATLAB/Simulink, which is suitable for the designing and analyzing the control system. We also evaluated a method of controlling the variable inductor with an asymmetric half-bridge converter.
