韩乃峥;贾秀芳;许建中;赵成勇;

• 1:新能源电力系统国家重点实验室(华北电力大学)

摘要(Abstract)：

直流电网已成为未来电网的重要发展方向,然而如何将孤立站平滑地接入运行中的直流电网中仍没有成熟的解决方案。在充分利用换流站的结构特点、不加入额外设备的情况下,通过控制直流线路正、负极直流断路器(DC circuit breaker,DCCB)的闭合时序,提出了孤立站在线平滑接入直流电网的控制策略。详细分析了每次断路器闭合后子模块电容的充电电路,计算了断路器闭合时的冲击电流。在该控制策略下,由于充电回路中大电阻的存在,断路器闭合时的冲击电流足够小,因此可以实现孤立站的平滑接入。另外,为最大程度得减小解锁瞬间对原系统的冲击,提出了四阶段控制策略。在PSCAD/EMTDC仿真环境下搭建了直流电网模型,仿真验证了所提出控制策略的有效性。

关键词(KeyWords)： 模块化多电平换流器;直流电网;直流断路器;平滑接入

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金项目(51777072);; 教育部中央高校基本科研业务费专项资金资助项目(2017MS002)~~

作者(Author): 韩乃峥;贾秀芳;许建中;赵成勇;

Email:

DOI: 10.13335/j.1000-3673.pst.2017.1883

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