摘要
提出一种交流侧并联功率解耦电路的无电解电容光伏逆变器。该光伏逆变器主电路采用电压型H桥,功率解耦电路采用一种七开关双向变换器结构,并联在逆变器交流输出侧。H桥变换器采用电流滞环控制以实现交流并网,功率解耦电路采用基于脉冲能量的控制方式,即根据每个开关周期需要解耦的能量大小计算功率开关的占空比。功率解耦电路采用峰值电流控制,从而加大解耦电容上电压纹波,降低解耦电容器容值,以实现无电解电容的目的。分析了并联功率解耦电路的四个工作模式,讨论了解耦电感和电容的参数设计。建立了提出的无电解电容光伏逆变器的Matlab仿真模型以验证其有效性。仿真结果表明,提出的功率解耦电路解耦电容的容值降低到几十μF,可实现无电解电容器的光伏逆变器,从而延长光伏逆变器的使用寿命。
A non-electrolytic capacitor PV inverter based on power decoupling circuit in parallel with AC side is presented.The main circuit of proposed inverter adopts the traditional voltage source H-bridge circuit and power decoupling circuit uses a novel double-direction converter with seven switchers,it is connected with AC side of PV inverter.The current hysteresis controller is used in H-bridge converter to realize grid integration and a new control strategy named as pulse energy modulation is adopted in power decoupling circuit.According to the decoupling energy needed by power decoupling circuit,the duty of power device is calculated.Power decoupling circuit adopts the control strategy named peak current controller,which can decrease the capacitance values of decoupling capacitor and make the non-electrolytic capacitor PV inverter come true by increasing the voltage ripple on the decoupling capacitor.The four different operating models of power decoupling circuit are analyzed and the parameters of decoupling inductor and decoupling capacitor are designed.The proposed non-electrolytic capacitor PV inverter and its control strategy are simulated by Matlab/Simulink.The experimental results show that the power decoupling circuit of proposed micro-inverter is effective and can reduce the value of the decoupling capacitor to several tensμF.In this way,it can realize the non-electrolytic capacitor PV inverter,thereby increasing its lifetime.
作者
舒展
程思萌
杨越
陶翔
章勇高
SHU Zhan;CHENG Simeng;YANG Yue;TAO Xiang;ZHANG Yonggao(Jiangxi Electric Power Company Electric Power Research Institute,Nanchang 330096,China;School of Electrical and Automation Engineering East China Jiaotong University,Nanchang 330013,China)
出处
《电力系统保护与控制》
EI
CSCD
北大核心
2019年第2期87-94,共8页
Power System Protection and Control
基金
国家自然科学基金项目资助(51467006
51467005)
江西省科技厅专项资助(20161BBH80032)
江西省教育厅项目资助(GJJ160489)~~
关键词
功率解耦
光伏逆变器
峰值电流
脉冲能量控制
power coupling circuit
PV inverter
peak current
pulse energy modulation
