采用计算机通讯的混合储能系统在光伏电站低电压穿越中的应用

Application of hybrid energy storage system based on computer communication in LVRT of photovoltaic power stations

近年来,由于具有绿色环保,取之不尽等特点,可再生能源发电系统成为全球研究热点之一。但是其存在着诸如低电压穿越等条件的限制,影响了新能源并网发电。文章以光伏电站为背景,首先提出利用混合储能系统协助光伏电站单台逆变器抵御低电压穿越的控制策略,采用滑动平均函数,提取低电压穿越时波动功率的直流分量,利用铅酸蓄电池和超级电容不同特性,使蓄电池吸收波动功率中直流缓变分量,保证能量平衡,超级电容处理交流突变分量,维持直流母线电压稳定。该控制策略既满足了光伏并网逆变器低电压穿越的要求,又保证了储能元器件的寿命。然后利用计算机网络通讯技术,通过合理配置不同并网逆变器蓄电池的SOC状态,保证光伏电站内部不同逆变器的蓄电池能量维持在合理范围,能够及时吸收或者释放能量。最后给出了逆变器控制策略的仿真和实验结果,同时也使用C#编写了蓄电池SOC管理软件,进行了测试,仿真和实验结果都验证了文中提出的控制策略的可行性。

In recent years, with the eco-friendly and inexhaustible characteristics, renewable energy generation system becomes one of the hot topics in the world.But there are some limitations, such as low voltage ride through.This pa-per proposes a control method using hybrid energy storage system to solve the power quality problem of low voltage ride through in photovoltaic power stations.Through moving average function, DC component of the fluctuating power in LVRT is extracted.DC graded component is absorbed by the storage batteries, through utilizing the different factors of lead-acid battery and super capacitor.Super capacitors are used to absorb AC component to maintain the DC bus volt-age .This method can help photovoltaic power stations meet the requirments for low voltage ride through and extend the life of batteries.Based on computer communication technology, the SOC of batteries can be set among a proper range to absorb or release energy.The simulation and experiment results of the proposed control method are shown in the end and the SOC management program is written in C#.The results verify the feasibility and reliability of the proposed system.