A Terminal Voltage Estimation and Unbalance Compensation Strategy Based on Double Synchronous Reference Frame for Shore Power Supply

Abstract

In this paper, a strategy of terminal voltage estimation unbalance compensation for shore power supply is proposed. In this strategy, based on double synchronous reference frame, sequence components are extracted from the measured current and voltage fast and precisely. And then, the terminal voltage could be accurately estimated under the equivalent circuit in the form of vector. At last, a simple and robust method is applied for voltage compensation, from which independent adjustability on the magnitude and the phase of both positive and negative sequence of terminal voltage can be achieved. The proposed strategy is simulated in PSCAD. The simulation results show that, by this strategy, the terminal voltage can be rapidly compensated to be fully balanced and adjusted to the demanded phase within 15ms.