Microinverters for single phase grid connections have an inherited issue which is commonly known as double line frequency problem. The problem is about the power pulsations of the AC grid which is double the line frequency. This power is time varying in nature while the power output from the PV module is constant (MPPT is used ). This is shown in Fig.1. This means that there must be some storage device for balance of power. This storage device is often called as decoupling capacitor.