Hysteresis-based PI state control of grid-connected voltage source converter with LCL filter for power conditioning

Particularly regarding the continuous development towards power systems with high penetration level of decentralized power generation units based on renewable energy sources, active power filters with energy storage capabilities are applied to perform grid supporting and stabilizing measures. Such devices, which are here referred to as power or grid conditioning systems, require appropriate control of the power converter. This paper proposes a hysteresis-based PI state control method to control the output current of a shunt-type power conditioner with an LCL filter. Investigations by means of simulations conducted in Matlab/Simulink show the dynamic performance and effectiveness of the presented control method, especially with respect to active resonance damping characteristics.