DQ-axis Synchronous Reference Frame based P-Q Control of Grid Connected AC Microgrid

Abstract

A simple real and reactive power (P-Q) control method based on synchronous reference DQ-axis frame theory for a grid-connected AC microgrid has been proposed in this paper which was validated using real time simulation tool real time digital simulator (RTDS). The proposed control method consisted of two control loops where proportional integral (PI) controllers have been used at the outer real and reactive power control loops to produce reference d-axis and q-axis currents respectively. Then, dq frame currents are controlled in inner closed loop using PI controllers to produce the reference voltage for generating appropriate control signals. The effectiveness of the proposed P-Q controller has been verified for the cases like load change, solar irradiation change and by changing both solar irradiation and load. Outcome of the simulation study has demonstrated the efficacy of the proposed DQ-axis synchronous reference frame based P-Q controller for real-time operation of grid-connected AC microgrid.