| 引用本文: | 薛英林,赵 峥,葛风雷,张哲任.基于投旁通对策略的组合式C-MMC单元投退控制[J].电力自动化设备,2015,35(12): |
| XUE Yinglin,ZHAO Zheng,GE Fenglei,ZHANG Zheren.Converter unit on ／ off control based on bypass pairs for combined C-MMC system[J].Electric Power Automation Equipment,2015,35(12): |
|
| 摘要: |
| 采用换流单元串并联的组合式基于箝位双子模块的模块化多电平换流器（C?鄄MMC）是柔性直流系统实现高压大容量输电的有效途径。针对工程实际中如何完成换流单元在线投退的问题， 首先将换流单元的投退过程分为并联类和串联类2种基本模式，讨论了投退过程存在的技术难点。其次，设计了旁路开关和隔离开关的配置方案以及箝位双子模块串接电阻的限流方案。然后，重点针对串联类单元投退，提出了一种基于投旁通对的控制策略。其核心思想是单元投退过程中以某一相桥臂为旁通对同时闭锁剩余两相桥臂，使得直流电流在换流单元和旁路开关间平稳转移；桥臂闭锁期间箝位二极管所串联的电阻有效抑制充电电流，减少模块电容电压的上升幅值。PSCAD／EMTDC仿真结果验证了所提方案的有效性。 |
| 关键词: 模块化多电平换流器 箝位双子模块 桥臂闭锁 阻尼电阻 控制 |
| DOI： |
| 分类号: |
| 基金项目: |
|
| Converter unit on ／ off control based on bypass pairs for combined C-MMC system |
|
XUE Yinglin1, ZHAO Zheng1, GE Fenglei2, ZHANG Zheren3
|
|
1.State Power Economic Research Institute，Beijing １０２２０９，China;2.State Grid Xuzhou Power Supply Company，Xuzhou 220005，China;3.Ｃｏｌｌｅｇｅ of Electricａｌ Engineering，Zhejiang University，Hangzhou 310027，China
|
| Abstract: |
| The combined C-MMC （Modular Multilevel Converter applying Clamp dｏｕｂｌｅ submodule） with converter units connected in series and parallel is adopted to achieve the high-voltage and large-capacity power transmission. Two basic patterns，series-type and parallel-type，are classified for the switch-on／off process of converter unit in the practical project and the technical difficulties of each type are analyzed. The configuration scheme of bypass／disconnecting switches and the current limiting scheme of series resistors in clamp dｏｕｂｌｅ submodule are designed. A strategy based on the bypass pair control is proposed for the series-type unit switch-on／off，which takes the arms of one phase as the bypass pair while blocks the arms of other phases during the unit switch-on／off to smoothly transfer the direct current between the converter unit and the bypass switch. For the blocked arms，the resistor connected to the clamping diode in series effectively suppresses the charging current and damps the increase of module capacitor voltage. The effectiveness and feasibility of the proposed strategy are verified by the results of PSCAD／EMTDC simulation. |
| Key words: modular multilevel converter clamp dｏｕｂｌｅ submodule arm blocking damping resistor control |
