Sliding mode-based multi-loop current control of a LCL grid-tied converter

This paper presents a current control method for LCL grid-tied converters using sliding mode algorithm in a multi-loop framework. The inner loop is implemented through a sliding mode approach to obtain fast and robustness convergence. The capacitor voltage is controlled in the inner control loop making this variable to behave like a controlled voltage source. The reference for the inner control loop is given by the outer loop. The outer loop can then be simply designed as simple L grid-tied converter. Simulation results demonstrate the performance of the proposed control strategy and show good tracking capability of the proposed scheme. Moreover, Hardware in the Loop simulation results are obtained in order to evaluate the performance of the proposed control law running on Digital Signal Processor.