Large-Signal Stabilization of Three-Phase VSR with Constant Power Load

Abstract

Abstract:As an important interface converter, the three-phase voltage-source rectifier (VSR) connects the grid to DC-input converters. The constant power load (CPL) characteristic of the converter-load often causes large-signal stability problems. In order to solve this problem, the stability boundary of the VSR with CPL is analyzed based on the mixed potential theory, and the stability condition under large-signal disturbance is obtained; thus, the jump range of the load power can be estimated. To improve the stability of the system, a voltage loop control scheme based on ADRC is proposed. A theoretical analysis based on the mixed potential theory shows the proposed scheme expands the power jump range of the VSR with CPL effectively, and improves its disturbance rejection performance. Finally, experimental results prove the effectiveness of the proposed control scheme.