The popular solar controllers on the market mainly include ordinary solar controllers, PWM solar controllers and MPPT solar controllers.

The working principle of the ordinary solar controller is to directly connect the output of the solar panel to the battery port, and disconnect it when the battery is full. Because of the internal resistance of the battery, it is difficult to fully charge the battery, and the solar panel is not fully utilized. The charging conversion efficiency is only 70-76%.

PWM refers to pulse width modulation. The PWM solar controller uses the digital output of the microprocessor to control the analog circuit, which is a method of digitally encoding the analog signal. Controlling the analog circuit digitally can greatly reduce the cost and power consumption of the system, and the charging conversion efficiency is 75-80%.

MPPT (Maximum Power Point Tracking) refers to the maximum power tracking. The MPPT solar controller can detect the power generation voltage of the solar panel in real time, and track the highest voltage and current value (VI), so that the system can charge the battery with the maximum power output, and the MPPT tracking efficiency It is 99%, and the power generation efficiency of the whole system can be as high as 97%.