一种具有MPPT功能的光伏逆变器下垂控制方法  

Droop control method for PV inverters with MPPT ability

作　　者：秦建衡 罗朝旭 刘洋 QIN Jianheng;LUO Zhaoxu;LIU Yang(College of Electrical&Information Engineering,Hunan University of Technology,Zhuzhou Hunan 412007,China;Zhengzhou Coal Mining Machinery Group Limited company,Zhengzhou Henan 450016,China)

机构地区：[1]湖南工业大学电气与信息工程学院,湖南株洲412007 [2]郑州煤矿机械集团股份有限公司,河南郑州450016

出　　处：《电源技术》2023年第3期398-402,共5页Chinese Journal of Power Sources

基　　金：国家自然科学基金青年项目(52207205)。

摘　　要：单相光伏并网系统中各单元之间普遍需要通信互联,降低了系统的可靠性且不易于扩展,在离网模式下,MPPT算法容易导致过压和过充现象。针对上述问题提出一种能实现MPPT功能的单相光伏逆变器下垂控制方法,该方法对传统下垂控制方程重新构造,将光伏电池阵列的P-V特性曲线导数dp_(pv)/dv_(pv)引入到下垂控制中,通过控制逆变器的输出功率直接调整光伏电池阵列的输出电压,从而实现最大功率点跟踪。所提方法无需复杂的MPPT控制算法,保留了下垂控制的无互联通信和“即插即用”等优点,在离网模式且负荷容量不超过系统带载能力的条件下,可实现功率均分。最后仿真结果验证了所提方法的正确性和有效性。Communication is generally required between units in single-phase photovoltaic grid connected system,which reduces the reliability of the system and is not easy to expand.Otherwise,in the off-grid mode,the MPPT algorithm is prone to overvoltage and overcharge.To overcome the above problems,a droop control method of single-phase photovoltaic inverter that could realize MPPT function directly was proposed.The proposed method introduced the derivative(dp_(pv)/dv_(pv))of P-V characteristic curve of photovoltaic cell array into traditional droop control equation,then the output voltage of the photovoltaic cell array was directly adjusted by controlling the output power of the inverter to achieve maximum power point tracking.This proposed method didn’t need the complex MPPT control algorithm,and retained the advantages of traditional droop control such as no interconnection communication and"plug and play".It was noted that,in the offgrid mode,power sharing between inverters could be achieved if the load capacity did not exceed the load capacity of the system.Finally,the simulation results verify the correctness and effectiveness of the proposed method.

关 键 词：光伏并网逆变器 下垂控制 最大功率点跟踪 

分 类 号：TM615[电气工程—电力系统及自动化]