摘要
高比例户用光伏接入低压配电网导致电压越限和波动。为了弥补集中控制无法快速响应光伏随机性、就地控制难以实现整体协调的问题,提出了一种光伏逆变器集中–就地两阶段电压–无功控制方法。就地控制采用变斜率下垂控制模型,利用电压灵敏度理论整定关键控制参数,确保极端场景下能有效抑制电压越限;集中控制以网损最小为目标,不同于一般集中控制对具体无功输出进行优化,根据光伏和负荷预测数值对就地控制的电压–无功下垂斜率进行优化;集中控制阶段在分钟级尺度上进行全网优化,就地阶段则根据实时量测动态调整本地无功输出。仿真结果表明所提控制方法在光伏和负荷预测误差较大情况下也能有效抑制电压越限,降低电压波动并改善网络损耗。
Integration of high-proportion residential photovoltaics(PVs) causes voltage violations and fluctuations. In order to mitigate the problems that it is difficult for central control to respond PVs’ randomness and for local control to achieve overall coordination, this paper proposes a two-stage Volt-var control strategy for PV inverters. The local control adopts a model with changeable droop rates, tuning key parameters based on voltage sensitivity theory to avoid voltage violations in the worst scenarios. The central control, aiming at minimizing power losses, optimizes the Volt-var droop rates of the local control rather than specific reactive power values in general central strategies. The central control stage firstly performs the optimization in timescale of minutes, then the local control stage dynamically regulates reactive power in real time according to measurements. Simulation results demonstrate that the voltage violations and fluctuations can be effectively mitigated even under forecast errors, while power losses and voltage fluctuations can also be reduced.
作者
蔡永翔
唐巍
张博
李天锐
王照琪
高博
CAI Yongxiang;TANG Wei;ZHANG Bo;LI Tianrui;WANG Zhaoqi;GAO Bo(College of Information and Electrical Engineering,China Agriculture University,Haidian District,Beijing 100083,China;State Grid Anhui Electrical Power Research Institute,Hefei 230601,Anhui Province,China)
出处
《电网技术》
EI
CSCD
北大核心
2019年第4期1271-1279,共9页
Power System Technology
基金
国家电网公司科技项目(提高光伏扶贫地区电网消纳能力与保障技术的研究与应用)~~
关键词
低压配电网
电压越限
高比例户用光伏
电压-无功控制
逆变器
low-voltage distribution network
voltage violation
high-proportion residential photovoltaics
Volt-var control
inverters
作者简介
蔡永翔(1991),男,博士研究生,主要研究方向为分布式光伏并网,交直流混合配电网,E-mail:lpscaiyx@163.com;通信作者:唐巍(1971),女,教授,博士生导师,主要研究方向为配电网规划与评估、配电网经济安全运行、分布式发电与微电网技术,E-mail:wei_tang@cau.edu.cn;张博(1994),女,博士研究生,主要研究方向为分布式光伏并网、主动配电网经济运行,E-mail:zhangbo1223@fbxmail.com。
