摘要
针对特高压直流(ultra-high voltage direct current,UHVDC)运行过程中一极直流线路故障重启时对另一健全极运行产生影响的问题,考虑双极直流线路间的互感,对暂态过程中双极电气量特征进行深入研究。根据暂态过程中的电压计算公式,对双极之间的影响进行了数值计算和物理解释并对影响功率跌落的因素进行分析,在已有健全极短时闭锁低压限流功能(voltage dependent current limit,VDCL)的控制措施基础上提出了多项控制策略。以天中直流为研究对象,通过实时数字仿真(real-time digital simulator,RTDS)系统建立与实际一次系统和实际控制保护程序完全一致的仿真模型,对改进策略进行优化比较研究,验证了在故障极重启期间健全极整流侧采用定电压控制以及改变健全极的电流控制器参数两项控制措施的有效性,最后提出了工程应用建议。
Considering mutual inductance between bipolar DC transmission lines in ultra-high voltage direct current（UHVDC） projects,bipolar characteristics during restarting of one pole after line fault occurring were analyzed and researched.According to voltage calculation formula for transient fault on transmission line,several improved control strategies were proposed on basis of the control measures that voltage dependent current limit（VDCL） function of the non-fault pole was blocked shortly.Comparative study of the strategies was presented based on close-loop simulation of a UHVDC system consisting of real-time digital simulator（RTDS） and control and protection equipment.Effectiveness of the two control methods adopting constant DC voltage control at rectifier side and changed parameters of current controller was confirmed.Then suggestion on project application was put forward.
出处
《电网技术》
EI
CSCD
北大核心
2017年第11期3547-3552,共6页
Power System Technology
基金
国家电网公司科技项目(XT71-15-049)~~
