This paper gives an overview of previous studies on photovoltaic(PV) devices, grid-connected PV inverters,control systems, maximum power point tracking(MPPT)control strategies, switching devices and transformer-less i...This paper gives an overview of previous studies on photovoltaic(PV) devices, grid-connected PV inverters,control systems, maximum power point tracking(MPPT)control strategies, switching devices and transformer-less inverters. The literature is classified based on types of PV systems, DC/DC boost converters and DC/AC inverters,and types of controllers that control the circuit to ensure maximum power tracking and stabilization of load and input voltage. This is followed by the theoretical background of PV devices, an overview of MPPT controllers and common mode leakage current, and a detailed investigation of different inverter topologies regarding the ground leakage current. Furthermore, design principles of power converters, such as DC/DC boost converters, and single-phase inverters are discussed. The paper also discusses limitations and benefits in addition to the basic operating principles of several topologies. Finally, the proposed system is derived and its simulation results are discussed to offer the next generation of grid connected PV systems.展开更多
提出一种单级式光伏并网逆变器的无电流检测最大功率点跟踪(maximum power point tracking,MPPT)方法。研究光伏组件、输入滤波电容和并网逆变器之间的能量耦合关系,通过使得连续两个并网功率周期的逆变器输出功率相等,通过计算输入滤...提出一种单级式光伏并网逆变器的无电流检测最大功率点跟踪(maximum power point tracking,MPPT)方法。研究光伏组件、输入滤波电容和并网逆变器之间的能量耦合关系,通过使得连续两个并网功率周期的逆变器输出功率相等,通过计算输入滤波电容电压的变化值,获得光伏组件输出功率的变化方向,实现了无电流检测的MPPT。划分光伏组件的3种工作区域,详细分析系统在各工作区域的稳定性,并给出具体的扰动准则。搭建200W的实验样机,实验结果充分证明了提出的控制方法的可行性和有效性。展开更多
分析母线电压崩溃现象,根据母线电压失稳与最大功率匹配之间的对应关系,提出只需直流电压采样的MPPT算法。该算法通过判断母线电压是否迅速跌落来鉴别最大功率点,具有实现简单、抗干扰能力强、适应局部阴影条件等优势。最后在自行研制...分析母线电压崩溃现象,根据母线电压失稳与最大功率匹配之间的对应关系,提出只需直流电压采样的MPPT算法。该算法通过判断母线电压是否迅速跌落来鉴别最大功率点,具有实现简单、抗干扰能力强、适应局部阴影条件等优势。最后在自行研制的一套630 k W光伏并网逆变系统上验证该算法的有效性和优越性。展开更多
文摘This paper gives an overview of previous studies on photovoltaic(PV) devices, grid-connected PV inverters,control systems, maximum power point tracking(MPPT)control strategies, switching devices and transformer-less inverters. The literature is classified based on types of PV systems, DC/DC boost converters and DC/AC inverters,and types of controllers that control the circuit to ensure maximum power tracking and stabilization of load and input voltage. This is followed by the theoretical background of PV devices, an overview of MPPT controllers and common mode leakage current, and a detailed investigation of different inverter topologies regarding the ground leakage current. Furthermore, design principles of power converters, such as DC/DC boost converters, and single-phase inverters are discussed. The paper also discusses limitations and benefits in addition to the basic operating principles of several topologies. Finally, the proposed system is derived and its simulation results are discussed to offer the next generation of grid connected PV systems.
文摘提出一种单级式光伏并网逆变器的无电流检测最大功率点跟踪(maximum power point tracking,MPPT)方法。研究光伏组件、输入滤波电容和并网逆变器之间的能量耦合关系,通过使得连续两个并网功率周期的逆变器输出功率相等,通过计算输入滤波电容电压的变化值,获得光伏组件输出功率的变化方向,实现了无电流检测的MPPT。划分光伏组件的3种工作区域,详细分析系统在各工作区域的稳定性,并给出具体的扰动准则。搭建200W的实验样机,实验结果充分证明了提出的控制方法的可行性和有效性。
