| 引用本文: | 刘 黎,杨仁炘,施 刚,等.含电流内环的构网型MMC新型交流电压构建策略及参数设计[J].电力系统保护与控制,2025,53(7):27-39.[点击复制] |
| LIU Li,YANG Renxin,SHI Gang,et al.A novel AC voltage control strategy with inner current loop and its parameter design for a grid-forming MMC[J].Power System Protection and Control,2025,53(7):27-39[点击复制] |
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| 摘要: |
| 构网型控制是电力电子变流器支撑新能源主导电力系统稳定运行的一种有效技术途径。高压大功率场景下，构网变流器通常采用模块化多电平(modular multilevel converter, MMC)拓扑。MMC无集中滤波电容、难以获取并网电流前馈的特性使得常规构网型控制中，交流电压-交流电流级联控制回路的性能恶化。为此，提出了一种新型交流电压控制策略，在保留电流内环限流能力的同时，将电流内环通过戴维南-诺顿等效变换成受控电压源串联虚拟阻抗的形式，实现了与同步发电机类似的端电压构建机制。在此基础上，基于小信号状态空间模型对控制环节及控制参数进行了优化设计。最后，在PSCAD/EMTDC平台进行仿真，结果验证了所提新型构网策略及参数设计方法的有效性。 |
| 关键词: 模块化多电平换流器 柔性直流输电 构网型控制 电流内环 交流电压控制 |
| DOI：10.19783/j.cnki.pspc.240774 |
| 投稿时间：2024-06-20修订日期：2024-11-01 |
| 基金项目:国家自然科学基金项目资助(52107201)；国家电网浙江省公司科技项目资助(5211ZS2000GR) |
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| A novel AC voltage control strategy with inner current loop and its parameter design for a grid-forming MMC |
| LIU Li1,2,YANG Renxin1,SHI Gang1,ZHANG Chen1,ZHANG Jianwen1,CAI Xu1 |
| (1. Department of Electrical Engineering, School of Electronic Information and Electrical Engineering, Shanghai
Jiao Tong University, Shanghai 200240, China; 2. Zhoushan Power Supply Company, State Grid
Zhejiang Electric Power Corporation, Zhoushan 316000, China) |
| Abstract: |
| Grid-forming (GFM) control is an effective way for power electronic converters to enhance the stability of a power system dominated by renewable power sources. In high-voltage and high-power application scenarios, GFM converters usually adopt modular multilevel converter (MMC) topology. Because of the absence of a centralized filter capacitor on the MMC AC side and the difficulty in obtaining current feedforward, the performance of AC voltage-AC current cascade control loops in conventional GFM control methods may deteriorate. To address this, a novel AC voltage control strategy is proposed. While retaining the current limiting capability, the current inner loop is transformed into a controllable voltage source in series with a virtual impedance using the Thevenin-Norton equivalent, thereby achieving a terminal voltage construction mechanism similar to that of synchronous generators. Moreover, the control loops and parameters are optimized using small signal state space modelling. Finally, simulation results in PSCAD/EMTDC prove the effectiveness of the proposed strategy and parameter design method. |
| Key words: MMC VSC-HVDC grid-forming control inner current loop AC voltage control |
