The function of photovoltaic inverter

The function of photovoltaic inverter

The inverter not only has the function of direct AC conversion, but also has the function of maximizing the performance of the solar cell and the function of system fault protection. Summed up, there are automatic operation and shutdown function, maximum power tracking control function, anti-independent operation function (for grid-connected systems), automatic voltage adjustment function (for grid-connected systems), DC detection function (for grid-connected systems), DC grounding detection function (for grid-connected systems). 

The functions of automatic operation and shutdown and maximum power tracking control are briefly introduced here:
1. Automatic operation and shutdown function after sunrise in the morning, the solar radiation intensity gradually increases, the output of the solar cell also increases, when the inverter work required after the output power, the inverter automatically starts to run. After the operation, the inverter will monitor the output of the solar cell module from time to time. As long as the output power of the solar cell module is greater than the output power required by the inverter to work, the inverter will continue to run until the sunset stop, even if the inverter can run in rainy days. When the output of the solar cell module becomes smaller and the output of the inverter is close to 0, the inverter will be in standby state. 

2. The maximum power tracking control function of the solar cell module output is changed with the solar radiation intensity and the solar cell module itself temperature (chip temperature). In addition, the solar cell module has the characteristic of voltage decreasing with the increase of current, so there is an optimal operating point to obtain the maximum power. The intensity of solar radiation varies, and obviously so does the optimal working point. Relative to these changes, the operating point of the solar cell module is always at the maximum power point, and the system always obtains the maximum power output from the solar cell module. This control is the maximum power tracking control. The most important feature of the inverter used in solar power system is that it includes the function of maximum power point tracking (MPPT).