Hardware-in-the-Loop Demonstration of a Grid-Connected Voltage-Sourced Converter with an LCL Filter

Abstract

This paper studies the transient behavior and resonance mitigation performance of a grid-connected voltage-sourced converter (VSC) under several control strategies using hardware-in-the-loop (HIL) simulation. Many VSCs use LCL filters to increase their power quality. However, an LCL filter may increase the possibility of resonance. Therefore, controllers need to include an active damping feature to improve the transient behavior of the system. There are several active damping current controllers such as 1) internal model control, 2) virtual RC damping control, and 3) notch filter control methods. This paper discusses the overshoot, rise time, and dq-axis current decoupling feature for each controller using HIL simulation case studies performed in the OPAL-RT real-time platform.