A new control scheme for circulating current minimization in high frequency AC power distribution architecture with multiple inverter modules operated in parallel

Abstract

The control issue of multiple inverter module operation (MIMO) is investigated for high frequency AC power distribution architecture, where multiple high frequency resonant inverters are connected in parallel to the high frequency, high voltage low current (HVLC) AC bus, to feed a number of point-of-use-power-supplies. The circulating current in MIMO is analyzed first. A novel control scheme is proposed based on the active and reactive current decomposition concept. In the proposed control, there are two loops, the current sharing control loop and voltage feedback control loop. For the current sharing loop, active current and reactive current are controlled separately. It is shown that the minimization of circulating current can be achieved if both the active currents and reactive currents are evenly distributed among activated inverter modules. This method is superior to the scalar control where only magnitudes of the currents are controlled. Performance is verified for both steady state and transient conditions