摘要
针对光伏发电与电压源换流器高压直流输电(voltagesource converter-high voltage direct current,VSC-HVDC)系统直流电压等级不匹配问题,提出了一种新的光伏电站经VSC-HVDC并网拓扑和控制策略,研究了该并网方案中光伏电站的运行特性,分析了单个光伏发电单元的控制策略和串联光伏发电单元支路故障控制策略;针对该拓扑结构中串联光伏发电单元效率易受不均匀辐照度影响的问题,提出了改进的电压源换流器(voltage source converter,VSC)直流侧电压斜率控制策略。在几种典型辐射情况下进行仿真,结果验证了所提控制策略的有效性,表明该方案可解决VSC-HVDC技术应用于光伏发电并网所面临的电压等级匹配问题。
In allusion to the mismatch between photovoltaic（PV） station and DC voltage class of voltage source converter-high voltage direct current（VSC-HVDC） system,a new topology of connecting PV station to power grid via VSC-HVDC and corresponding control strategy were proposed.The operational characteristics of PV station in the proposed grid-connecting scheme was researched and the control strategy for single PV generation unit and fault tolerant control strategy for the branch composed of cascade connected PV generation units were analyzed;to solve the problem that in the proposed topological structure the efficiency of cascade connected PV generation units was easy to be affected by unbalanced irradiance,an improved control strategy of voltage slope at DC side of voltage source converter（VSC） was put forward.The proposed control strategies were simulated under several typical irradiation conditions,and simulation results showed that the proposed control strategies were effective.
出处
《电网技术》
EI
CSCD
北大核心
2012年第11期41-45,共5页
Power System Technology
关键词
光伏电站
电压源换流器高压直流输电系统
并网
辐射不均匀
photovoltaic station
voltage source converter-high voltage direct current（VSC-HVDC） system
integration
unbalanced irradiance
