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