基于APFC芯片控制的光伏并网逆变器研究

提出一种基于有源功率因数校正(APFC)芯片控制的小功率光伏并网逆变器方案。该逆变器包括直流变换环节和逆变环节。其中直流变换环节采用APFC芯片控制将光伏电池板的直流低电压变换成正弦双半波的直流电,逆变环节采用工频全桥逆变电路将正弦双半波电流变换为交变电流注入电网。新方案中并网逆变器的并网控制采用APFC芯片实现,而实时控制要求低的最大功率点跟踪(MPPT)、孤岛保护可采用低价的单片机实现。新方案具有成本低、开发和电流采样容易等优点。通过一台300 W的样机证明了系统方案是正确有效的。

Research on Photovoltaic Grid-connected Inverter Controlled by APFC Controller

A scheme on PV grid-connected microinverter based on active power factor correction(APFC) controller is presented,including DC/DC link and DC/AC link.The DC/DC link transforms the low DC voltage of solar panels into high DC voltage,obtaining dual-half-sine-wave current output by using APFC controller,then the DC/AC link trans-forms dual-half-sine-wave current into alternating current.The output current of the inverter is controlled by APFC controller in the new scheme.It can use low-cost MCU for maximum power point tracking(MPPT) and islanding pro-tection.The scheme has many advantages,such as:low-cost,easy for developing and current sampling,etc.A prototype is developed and experimental results demonstrate the control scheme is correct and effective.