Optimized PI constant for current controller of grid connected inverter with LCL filter using Genetic Algorithm

摘要

This paper presents optimized PI constant for current controller of grid connected inverter with LCL filter. The controller consists of PI controller applied in Synchronous References Frame to control inverter current. To analyze the controller, the system should be modeled. Unfortunately the system is too complex. Therefore, to simplify the system, it is converted into a balanced single-phase model. Furthermore, the complexity of system increased the difficulties of PI constants tuning. To tune the PI constants, controller loop is formulated as an objective function with constraints of transient responses and steady state error. GA (Genetic Algorithm) will optimize simultaneously to obtain optimal values for the constants of PI controller. The GA algorithm is simulated under MATLAB. Then, the optimized PI constants are verified in circuit of PSIM Simulator. Simulation results confirm the method could determine PI constants for the best response.