A dual-loop model predictive voltage control/sliding-mode current control for voltage source inverter operation in smart microgrids

摘要

The design of a robust controller for the voltage source inverteris essential for reliable operation of distributed energy resourcesin future smart microgrids. The design problem is challenging in thecase of autonomous operation subsequent to an islanding situation.In this article, a dual-loop controller is proposed for voltage sourceinverter control. The outer loop is designed for microgrid voltage andfrequency regulation based on the model predictive control strategy.This outer loop generates reference inverter currents for the innerloop. The inner loop is designed using a sliding-mode control strategy,and it generates the pulse-width modulation voltage commandsto regulate the inverter currents. A standard space vector algorithmis used to realize the pulse-width modulation voltage commands.Performance evaluation of the proposed controller is carried out fordifferent loading scenarios. It is shown that the proposed dual-loopcontroller provides the specified performance characteristics of anislanded microgrid with different loading conditions.