Distributed Control of Multiple Electric Springs for Voltage Control in Microgrid

Abstract

Dispersed distribution of many inverter-based electric springs (ESs) over the power grid as a means to provide stability support for smart grid against high penetration of intermittent renewable power has been suggested recently. While single ES has its own local controller, their wide dispersion makes it difficult to coordinate multiple ESs operation. In this paper, a complete design and implementation procedure of the consensus control methodology for the distributed voltage control of multiple ES is presented. First, the specific control scheme for the single ES is designed by introducing the proportional resonant controller. Then, incorporating with the consensus algorithm by neighboring information exchange instead of global communication, the control strategy for multiple ESs is implemented to discover the voltage reference which will be assigned to ESs for tracking the reference voltage. Compared with the conventional droop control, the scheme can maintain the voltage level of the critical load without sacrificing the voltage control accuracy. Simulation results show that the distributed voltage control can guarantee the overall coordination of parallel ESs under various operation conditions.