CAJ | 학술논문

电压源换流器型高压直流(VSC-HVDC)输电控制系统复杂,故障承受能力差,线路保护装置动作正确率不高。文中提出了一种利用模量模型识别的 VSC-HVDC 输电线路纵联保护新原理。该原理将区外故障等效为正的电容模型,差动电流和差动电压导数相关系数为1；将区内故障等效为负的电容模型,差动电流和差动电压导数相关系数为-1。通过判别相关系数的正负,即可区分区内、区外故障。在实际运行中,VSC-HVDC输电系统多为双极运行,为降低极间电磁耦合的影响,采用了1模和0模量构成判据。理论分析和PSCAD仿真实验表明,新原理无需补偿输电线路电容电流,原理简单、易于整定,不受过渡电阻和控制特性的影响,在各种工况下均能快速可靠地区分区内、区外故障。
전압원환류기형고압직류(VSC-HVDC)수전공제계통복잡,고장승수능력차,선로보호장치동작정학솔불고。문중제출료일충이용모량모형식별적 VSC-HVDC 수전선로종련보호신원리。해원리장구외고장등효위정적전용모형,차동전류화차동전압도수상관계수위1；장구내고장등효위부적전용모형,차동전류화차동전압도수상관계수위-1。통과판별상관계수적정부,즉가구분구내、구외고장。재실제운행중,VSC-HVDC수전계통다위쌍겁운행,위강저겁간전자우합적영향,채용료1모화0모량구성판거。이론분석화PSCAD방진실험표명,신원리무수보상수전선로전용전류,원리간단、역우정정,불수과도전조화공제특성적영향,재각충공황하균능쾌속가고지구분구내、구외고장。
In view of the complexity of the control system of voltage source converter based HVDC (VSC-HVDC),its insufficient fault tolerance ability,and low correct rate of line protection device,a novel pilot protection for VSC-HVDC transmission lines using the modulus model identification is proposed.According to this principle,the external fault is equivalent to a positive capacitance model,so the correlation coefficient between the differential current and differential voltage derivative is 1;while the internal fault is equivalent to a negative capacitance model,so the correlation coefficient between the differential current and differential voltage derivative is -1 .So the internal faults and the external faults can be distinguished by j udging whether the correlation coefficient is positive or negative.In practice,modules are used to reduce the interpole electromagnetic coupling disturbance in the VSC-HVDC bipolar system. Theoretical analysis and PSCAD simulation experiments show that the new principle,without compensating for transmission lines capacitor current,is simple,easy to implement,and is not affected by transition resistance and control characteristics,while capable of identifying internal faults and external faults reliably and rapidly.