摘要
针对传统并网系统中应用的逆变器,输出电压电流的局限性、高次谐波含量大等缺点,提出将传统三相PWM并网逆变器和等效的Z源网络相结合,建立了三相Z源并网逆变器的数学模型。采用LCL滤波器对高次谐波进行滤波,LCL滤波器在低开关频率和电感较小的情况下较单电感滤波具有明显的优势。研究采用并网电流和电容电压双闭环控制策略对并网逆变器进行控制,给出了网侧电流分量的控制策略,以及外环电压设定值的约束条件。仿真结果验证了理论分析的正确性和控制策略的有效性。
Aiming at the shortcomings such as limitations of the output voltage and current,high harmonic content exsisting in the application of traditional grid inverter system,a mathematical model of a three-phase grid Z-source inverter combining the traditional three-phase PWM inverter with the equivalent Z-source network,is established.LCL filter is used to filter high-order harmonic.The LCL filter has obvious advantages comparing with single-inductor filters under the situation of low switching frequency and smaller inductor.The grid current and capacitance-voltage dual loop control strategy is applied to control the grid-connected inverter and the network side current component control strategy is given out,as well as the constraints of the outer ring voltage setting.Simulation results verify the validity of the theoretical analysis and the availibility of the control strategy.
出处
《电测与仪表》
北大核心
2015年第6期55-60,共6页
Electrical Measurement & Instrumentation
关键词
Z源逆变器
LCL滤波
电压电流双闭环
仿真分析
Z-source inverter
LCL filter
voltage and current double closed loop
simulation analysis
