Design of a Proportional Resonant Controller with Resonant Harmonic Compensator and Fault Ride Trough Strategies for a Grid-Connected Photovoltaic System

• Main Authors: Saif Ul Islam, Kamran Zeb, Waqar Ud Din, Imran Khan, Muhammad Ishfaq, Tiago Davi Curi Busarello, Hee Je Kim
• Format: Article
• Language: English
• Published: MDPI AG 2018-12-01
• Series: Electronics
• Subjects: photovoltaic system (PVS); distributed-energy-resources (DERs); PI controller; PR controller; low-voltage ride-through (LVRT); fault-ride through (FRT) strategy; switch-type fault current limiter (STFCL); crowbar strategy; point of common coupling (PCC); asymmetrical faults
• Online Access: https://www.mdpi.com/2079-9292/7/12/451

This paper presents the design and analysis of a proportional resonant controller with a resonant harmonic compensator and switch-type fault current limiter, as a fault-ride through strategy for a three-phase, grid-connected photovoltaic (PV) system under normal conditions and asymmetrical faults. The switch-type fault limiter comprised of current-limiting inductors, a bridge rectifier, a snubber capacitor, linear transformers, and energy absorption bypass. Furthermore, a critical and analytical comparison of switch-type fault limiters is carried out, with the conventional crowbar as the fault-ride through strategy, in combination with a conventionally tuned proportional integrator controller. The designed fault-ride through strategies with proportional integrator and proportional resonant controllers with resonant harmonic compensators are tested at the point of common coupling of the photovoltaic system and at a distance of 19 km from the point of common coupling, in order to analyze the impacts of fault parameter with respect to location. A MATLAB/Simulink model of a 100 kW three-phase grid-connected photovoltaic system is used for analysis. The simulation results of the proposed switch-type fault limiter with proportional resonant controller effectively validate the stable, ripple-free, and robust response compared to all other configurations. In addition, it is also verified that the grid faults on the PV system have a significant impact on fault type, and less impact on fault location.