Study on a single-loop MPC strategy for Grid-side converter

This paper proposed a single-loop Model Predictive Control (MPC) strategy for the Grid-side converter (GSC), which reduces the difficulty of controller design and improves the system transient performance. In field oriented control, double-loop cascade control structure is widely adopted by GSC system, but this control structure has some disadvantages, such as design and matching difficulty of inner and outer loop parameters, and controller delay. Therefore, there aspects are improved in this paper. First, a single-loop strategy is proposed for GSC to simplify the traditional cascade control structure and the system dynamic response capability is enhanced; Second, the integral discretization method is adopted to solve the predictive problem of second-order system, which reduces the predictive complexity; Third, to prevent over current cases, the current limit function is taken as a nonlinear additional term of cost function. Finally, the feasibility and effectiveness of the proposed control strategy are verified by simulation experiments.