A QPR-Based Low-Complexity Input Current Control Strategy for the Indirect Matrix Converters with Unity Grid Power Factor

Abstract

Unity grid power factor (GPF) is essential for the indirect matrix converter (IMC) applications to satisfy the grid-friendly requirement. The existing unity GPF control strategies usually consist of high-complexity structures, resulting in difficult parameter adjustments and high-speed processor requirements. In this paper, a low-complexity input current control (LCICC) strategy is proposed for the IMC operating at the unity GPF. Unlike the conventional strategies designed in the d - q synchronous coordinate frame, the proposed LCICC strategy is set up in the \alpha - \beta stationary coordinate frame. Then, the quasi-proportional resonant (QPR) controllers are utilized for a novel input current control manner, which is implemented to regulate the input currents based on the reconstructed grid voltage and current vectors. By this design, the proposed strategy can help to reduce the control complexity, with the advantages of the conventional closed-loop control strategies reserved. The steady-state and dynamic-state performance of the proposed strategy is validated by the experiments on a downscaled prototype. Besides, comparative experimental research with respect to an existing typical strategy indicates that the computational burden can be reduced 14.9% by the proposed strategy.