Full-order Terminal Sliding-Mode Control for LCL Type Grid-Side Converter

This paper investigates the robust control strategies for the LCL type grid-side converter. The voltage outer loop adopts the traditional voltage vector orientation control, and the main function is to stabilize the DC side voltage. The current inner loop is designed in the synchronous rotating coordinate system, and adopts full-order sliding mode control strategy. Two full-order sliding-mode controllers arc proposed to control the grid current to realize the unity power factor and on-grid. It is the most widely used control strategy that facilitates the design of grid-side filtering parameters. The time-varying gains in the controllers are constructed to reduce the waste of the control energy and avoid the overestimation of the bound of the system uncertainties. Finally, the simulation results validate the proposed method.