基于PQ-QV-PV节点的光储输出功率主动控制方法

摘要

The problem of voltage exceeding specified limits may occur when the photovoltaic is connected to the distribution network.The active power regulation ability of Energy Storage (ES) and the reactive power regulation ability of grid-connected photovoltaic inverter can provide support of active power and reactive power for distribution network to solve the problem of voltage exceeding specified limits and improve the penetration of photovoltaic.A strategy of actively controlling the output power for photovoltaic-storage system based on extended PQ-QV-PV node is proposed by analyzing the voltage regulating mechanism of Point of Common Coupling (PCC) of photovoltaic with energy storage by controlling photovoltaic inverter and energy storage when PV output fluctuates.The strategy firstly sets a small wave range of voltage to every photovoltaic,then according to the proposed active control strategy coverts the types of PV grid-connected nodes among PQ,QV,and PV successively based on voltage level of grid-connected node,thereby controls the grid-connected level into a smaller range considering power loss decrease.The simulation results indicate that the proposed method can solve the problem of voltage exceeding specified limits when photovoltaic is connected to electric distribution network.%光伏接入配电网易产生电压越限问题,储能的有功调压能力和光伏逆变器的无功调压能力可向配电网提供有功和无功支撑,以减少电压越限并提高光伏的渗透率.通过分析光伏出力波动时光伏逆变器和储能对光伏并网点的电压调节机理,提出了一种基于PQ-QV-PV节点转换的光储输出功率主动控制方法.该方法首先给各个光伏并网点设置一个较小的电压波动范围,其次依照所提的主动控制策略将光伏并网节点类型根据并网点电压水平依次在PQ、QV和PV节点之间进行转换,从而在考虑减少网损的基础上将并网点电压限制在较小的范围内.仿真分析结果表明,该方法能很好地解决光伏接入下的电压越限问题.