Nowadays wind energy is the fastest growing renewable energy resource in the world.The problems of integrating wind farms are caused by changes of wind speed during a day.Moreover,the behaviors of wind turbines equipp...Nowadays wind energy is the fastest growing renewable energy resource in the world.The problems of integrating wind farms are caused by changes of wind speed during a day.Moreover,the behaviors of wind turbines equipped with doubly-fed induction generators differ fundamentally from synchronous generators.Therefore,more considerations are needed to analyze the performances of the distance protection relays.The protection of a wind farm with distance relay is inspected.By changing the conditions of the wind farm,the characteristics of the distance relay are studied.展开更多
A simulation system for power grid with concentrated large-scale wind farm integration is established based on the electro-magnetic transient model of wind turbine equipped with doubly-fed induction generator (DFIG),w...A simulation system for power grid with concentrated large-scale wind farm integration is established based on the electro-magnetic transient model of wind turbine equipped with doubly-fed induction generator (DFIG),which is built by real-time digital simulator (RTDS).Using the hardware communication interface of RTDS,a closed-loop testing experiment is accomplished to study the impacts of large-scale wind farms on the existing relay protection devices for wind farm outgoing transmission line.This paper points out problems existing in current relay protection devices as follows:fault phase selector can select unwanted phase due to the changes of fault features caused by special network connection of wind farms;blocking condition for distance protections needs to be re-examined due to the weak power-feed characteristics of wind farms;and power frequency parameter based relay protection devices cannot accurately operate due to the special transient voltage and current characteristics of wind farms during fault period.Results lay the foundation for improving the performances of the existing relay protection device and developing new principle relay protection.展开更多
以双馈风力发电系统(doubly-fed induction generator based wind energy conversion system,DFIG-based WECS)为例,利用小信号分析法推导出由风机、双质量块传动链构成的动力与传动系统通用传递函数方程。动力与传动系统传递函数的零...以双馈风力发电系统(doubly-fed induction generator based wind energy conversion system,DFIG-based WECS)为例,利用小信号分析法推导出由风机、双质量块传动链构成的动力与传动系统通用传递函数方程。动力与传动系统传递函数的零极点位置、稳定性与系统参数及系统运行工作点相关。该传递函数可进一步分解为扭转分量和非扭转分量。传动链参数仅对扭转分量造成影响。在此基础上,建立了考虑动力传动、电机、变流器、控制等环节的风力发电系统传递函数模型。模型综合了各环节参数,可直观反映系统参数对系统响应的影响,有助于深入了解系统动态行为。算例及时域仿真结果证明了所提出传递函数模型的准确性和高效性,可为系统参数设计研究提供理论依据。展开更多
文摘Nowadays wind energy is the fastest growing renewable energy resource in the world.The problems of integrating wind farms are caused by changes of wind speed during a day.Moreover,the behaviors of wind turbines equipped with doubly-fed induction generators differ fundamentally from synchronous generators.Therefore,more considerations are needed to analyze the performances of the distance protection relays.The protection of a wind farm with distance relay is inspected.By changing the conditions of the wind farm,the characteristics of the distance relay are studied.
基金supported by the Special Fund of the National Basic Research Program of China (973 Program) (No.2009CB219704)
文摘A simulation system for power grid with concentrated large-scale wind farm integration is established based on the electro-magnetic transient model of wind turbine equipped with doubly-fed induction generator (DFIG),which is built by real-time digital simulator (RTDS).Using the hardware communication interface of RTDS,a closed-loop testing experiment is accomplished to study the impacts of large-scale wind farms on the existing relay protection devices for wind farm outgoing transmission line.This paper points out problems existing in current relay protection devices as follows:fault phase selector can select unwanted phase due to the changes of fault features caused by special network connection of wind farms;blocking condition for distance protections needs to be re-examined due to the weak power-feed characteristics of wind farms;and power frequency parameter based relay protection devices cannot accurately operate due to the special transient voltage and current characteristics of wind farms during fault period.Results lay the foundation for improving the performances of the existing relay protection device and developing new principle relay protection.
文摘以双馈风力发电系统(doubly-fed induction generator based wind energy conversion system,DFIG-based WECS)为例,利用小信号分析法推导出由风机、双质量块传动链构成的动力与传动系统通用传递函数方程。动力与传动系统传递函数的零极点位置、稳定性与系统参数及系统运行工作点相关。该传递函数可进一步分解为扭转分量和非扭转分量。传动链参数仅对扭转分量造成影响。在此基础上,建立了考虑动力传动、电机、变流器、控制等环节的风力发电系统传递函数模型。模型综合了各环节参数,可直观反映系统参数对系统响应的影响,有助于深入了解系统动态行为。算例及时域仿真结果证明了所提出传递函数模型的准确性和高效性,可为系统参数设计研究提供理论依据。