Research on Improved Coordination Control Strategy for Soft Open Point

doi:10.11985/2022.01.007

Abstract

Abstract:

Under the rapid development of distributed new energy technology, the coordinated control of each port of soft open point (SOP) is crucial to the stable operation of the distribution network. When the SOP adopts master-slave control, only the converter controlled by the fixed DC voltage participates in the regulation. However, when there is a large power fluctuation in the system, the problems of overshoot of the power of the main converter and over-limit of the DC side voltage appear. In order to prevent the stable operation of the system from being affected by only a single converter station performing power regulation, an improved coordinated control strategy is proposed. Using the DC voltage fluctuation and the imbalance of power in the system are relevance, was introduced to the rated power loop controller dc voltage follower change, make the inverter also participate in power regulation when the power imbalance in the system. This strategy enables multiple converters to participate in power regulation at the same time, and the SOP can be smoothly switched in different control modes. Finally, the PLECS simulation model of three-terminal SOP is built to verify the correctness and effectiveness of the improved coordination control strategy.

Key words: Soft open point, improved coordination control, power fluctuation, smooth switching

CLC Number:

TM561

ZHOU Feiyang, WANG Chuyang, ZHANG Li, LIN Jinjiao, KONG Xiangping, ZHENG Junchao. Research on Improved Coordination Control Strategy for Soft Open Point[J]. Journal of Electrical Engineering, 2022, 17(1): 49-55.

Figures/Tables 11

References 20

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参数	数值
开关频率f/kHz	10
桥臂电感L/mH	10
直流侧电压U_dc/kV	20
交流侧电压U_ac/kV	10
子模块数N	10
MMC1的额定有功容量P₁/MW	10
MMC2的额定有功容量P₂/MW	6
MMC3的额定有功容量P₃/MW	5