摘要
现有的直流输电线路纵联保护没有充分考虑控制特性的影响。该文分析得出换流器控制系统中受控电流偏差均值的故障特征。利用区内外故障时,两侧控制系统电流偏差均值特征不等式的差异,结合电流偏差与直流电流和电流指令的关系,提出纵联电流保护新原理。所提原理简单,无需电容电流补偿,并且充分利用了直流输电系统的控制特性。和纵联差动保护相比,所提原理拥有相同的耐过渡电阻能力,原理上无需暂态闭锁,动作速度快。和现有的纵联保护原理相比,所提原理动作区间长,可靠性高。数字仿真验证了所提方法的完备性和可靠性。
Currently used high voltage direct current（HVDC） transmission line pilot protections are not fully adapt to the influence of converter control characteristics. Fault characteristics of the average value of the PI controlled current error in both ends converters were analyzed. Internal and external faults are distinguishable by identifying the characteristic inequalities which consist with both ends average current errors. Using the characteristic inequalities and the relationship between current error and current order in HVDC control system, a novel pilot protection scheme was proposed. The proposed protection principle is simple, and does not require distributed capacitance compensation, and also fundamentally utilizes converter control characteristics. Comparing with current differential protection, the proposed principle has the identical high resistance tolerance, while does not require transient interlock and is fast reactive. Comparing with recent researches of pilot protection, the proposed protection has long operation zone and is more reliable. Digital simulations confirm the completeness and reliability of the proposed protection.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2016年第8期2159-2167,共9页
Proceedings of the CSEE
基金
国家自然科学基金项目(51177128
51477131)~~
关键词
高压直流
输电线路
纵联保护
电流偏差
控制特性
故障特征
high voltage direct current（HVDC）
transmission line
pilot protection
current error
control characteristic
fault characteristic
