光伏专用逆变器保护系统的设计

Design of the protection system of the inverter used for the photovoltaic system

光伏专用逆变器系统在实际运行时 ,既要有快速保护又要避免误动作 ,并兼顾实时性和可靠性。系统着重考虑了过载电流保护和短路电流保护。短路电流保护保证出现短路电流时及时封锁 SPWM输出 ,反时限保护保证系统具有短时过载能力 ;硬件保护具有快速性的特点 ,软件保护具有灵活性的特点。这就保障了系统硬件有欠压、短路电流保护 ,软件有过热、过放、过载保护。

When an inverter used for the photovoltaic system is running, all kinds of protection need to be taken into account, so that it can act in time and properly. Overload current protection and short circuit current protection are considered especially in this paper. When short current occurs, short circuit current protection closes off SPWM wave in time, and anti time limit protection enables the system to bear overload for a moment. The hardware protection has the high speed character; it includes low voltage protection and short circuit current protection. The software protection has flexibility; it includes overheat protection, overdischarge protection, overload protection.