An Improved Sliding Mode Control Scheme for T-type Rectifier Based on Deadbeat Control

Abstract

The power router (PR) for the low-voltage distribution network is the core equipment of energy internet (EI). As the connector between the power grid and DC bus of PR, the performance of the rectifier on the grid side and DC side will directly affect the PR. The traditional linear control strategy will deteriorate system performance in terms of the rectifier. Therefore, taking the three-level T-type rectifier (3LT2R) as the object, this paper proposes a double loop nonlinear control strategy. The inner current loop is a simplified deadbeat predictive control strategy based on improved space vector pulse-width modulation (SVPWM). The inner loop is designed to improve the dynamic performance of the grid side of the system and reduce the computational burden of the controller by changing the coordinate system of vector synthesis. And the outer voltage loop is a variable exponent sliding mode controller (SMC) based on an integral sliding mode surface. It is designed to ensure the robustness of the DC side of the 3LT2R and to weaken the chattering of SMC. Simulation and experimental results verify the effectiveness of the proposed strategy.