摘要
研究了具备低电压穿越(Low Voltage Ride-Through,LVRT)能力的光伏并网发电系统,送出线部分发生三相短路故障时,LVRT控制过程中发出的无功电流对传统比率制动式和新型标积制动式差动保护灵敏度的影响。理论分析表明故障期间无功补偿会导致两种差动保护的灵敏度下降,并通过Simulink搭建光伏并网发电系统仿真模型验证了这一结论。在此基础上,进一步对比得出发生金属性短路故障时,标积制动式差动保护的灵敏度受无功补偿影响较小,作为光伏电站送出线部分的保护效果更佳。最后通过差动特性曲线的整定方式,对如何提升差动保护灵敏度的问题提出改进建议。
The influence of reactive power compensation on sensitivity of differential protection of ratio-restraining characteristic and product-restraining characteristic is studied, when the output line of grid-connected photovoltaic （PV） systems with low voltage ride-through capability occurs three-phase short-circuit failures. It is found that the use of LVRT results in the decline of two kinds of sensitivity of the differential protection. The model of grid-connected photovoltaic （PV） system is set up, and verified by Simulink simulation. And further conclusion shows that the impact of differential protection of product-restraining characteristic on sensitivity is smaller, when the reactive power compensation is injected, and is better for the protection of output lines of photovoltaic power station, when the short-circuit fault occurs. Finally, this paper presents recommendations about how to improve the sensitivity of the differential protection by the tuning mode of differential characteristic curve.
出处
《电力系统保护与控制》
EI
CSCD
北大核心
2016年第4期51-56,共6页
Power System Protection and Control
关键词
LVRT
无功补偿
比率制动
标积制动
灵敏度
LVRT
reactive power compensation
ratio-restraint
product-restraint
sensitivity
作者简介
王秀莲（1965-），女，博士，教授，硕士生导师，研究方向为电力系统自动化、智能电网及新能源技术；
胡广（1989-），男，通信作者，硕士研究生，研究方向为光伏并网发电技术；E-mail：15910364042@163．com
毕大强（1973-），男，博士，高级工程师，研究方向为电力系统主设备继电保护、电力电子技术在电力系统中的应用。
