不平衡电网下并网逆变器的模型预测电流限幅灵活控制  

Flexible Model Predictive Control with Peak Current Limitation for Grid-Connected Inverter under Unbalanced Grid Voltage

作　　者：金涛[1] 沈学宇 苏泰新 郭敬东 Jin Tao;Shen Xueyu;Su Taixin;Guo Jingdong(Fujian Key Laboratory of New Energy Generation and Power Conversion Fuzhou University Fuzhou 350116 China;State Grid Fujian Electric Power Research Institute Fuzhou 350007 China)

机构地区：[1]新能源发电与功率变换福建省重点实验室福州大学,福州350116 [2]国网福建省电力有限公司电力科学研究院,福州350007

出　　处：《电工技术学报》2019年第11期2342-2353,共12页Transactions of China Electrotechnical Society

基　　金：欧盟FP7国际科技合作基金资助项目(909880);国家自然科学基金项目(61304260)资助

摘　　要：针对不平衡电网电压下,并网逆变器出现的功率波动和过电流问题,提出了一种并网逆变器不平衡及电流限幅模型预测控制方法。该方法以平衡电流、抑制有功和无功功率振荡为目标来设计电流参考发生器,然后通过功率参考发生器获取功率参考设定值与输出电流峰值阈值的定量关系,用于指导不平衡电网电压下的功率参考设定。在此基础上,利用空间矢量调制原理给出了基于参考电压建立代价函数法的并网模型预测电流控制策略,实现对参考电流的准确跟踪。仿真和实验结果表明,所提方法可以灵活地实现电网电压不平衡条件下的输出电流平衡、有功恒定或无功恒定的控制目标,且能有效限制平衡电流模式、恒定有功模式以及恒定无功模式下的电流峰值。In order to overcome the problem of power fluctuation and over-current in grid-connected inverters under unbalanced grid voltage,a flexible unbalanced control strategy based on model predictive control with peak current limitation for grid-connected inverters is proposed.This method is aimed at balancing the current,eliminating active and reactive power oscillations to design a current reference generator.The quantitative relationship between the power reference set value and the peak output current value is obtained through the power reference generator to guide the power reference setting under unbalanced grid voltage.On this basis,the control strategy of grid-connected model predictive current based on reference voltage to establish cost function method is given,and the reference current is accurately tracked.Simulation and experimental results show that the proposed method can flexibly realize the control of output current balance,active or reactive power constant under unbalanced grid voltage,and the current peak is limited effectively under the balance current,constant active and reactive power mode.

关 键 词：不平衡电网电压 并网逆变器 模型预测电流控制 电流峰值 

分 类 号：TM464[电气工程—电器]