Regardless of the technology used, the basic design of the inverter is very clear and often similar. The core is the process of converting DC voltage (photovoltaic modules) into AC voltage (grid connected). During the transformation process, the positive and negative connections of direct current are continuously converted, resulting in alternating current with varying directions. So, the key component of the inverter is the bridge switch, which connects one side of the switch bridge to the input DC power supply and the other side to the AC power grid. During the working process, only two opposite switches can be closed simultaneously. If the switching speed of this switch bridge is set to be the same as the frequency of the power grid, theoretically, the output side of the bridge can be connected to the power grid. However, since the output current is a square wave and the intensity remains unchanged, it is necessary to install an inductor with an iron core at the output end to control the output current to a sine wave shape. The disconnection of the bridge adopts a pulse process, which forms a smaller current component related to the pulse. This current component can control the current of the inductor. The frequency of the pulse is generally 20K, which can completely form a 50Hz current. (See Figure 1: b) For photovoltaic inverters, there is also a very important device that cannot be missed: the input capacitor, as shown in Figure 1: c, the container's function is to store electrical energy, ensure that the electricity from the power generation side is continuously and consistently supplied to the bridge switch, and enter the power grid through the bridge that changes with the grid frequency step. Only when the capacity of the input capacitor is large enough can the continuous and normal operation of the photovoltaic power generation system be guaranteed