PWM uses the digital output of microprocessor to control the analog circuit. The PWM solar controller solves the problems of insufficient battery charge and short battery life, but the solar panel is not fully utilized.

MPPT solar controller is a solar controller with maximum power point tracking function. MPPT solar controller can detect the voltage and current of solar panel in real time, and continuously track the maximum power (P = U * I), so that the system always charges the battery with the maximum power. The MPPT tracking efficiency is 99%, and the power generation efficiency of the whole system reaches 97%, and the battery charging stage is divided into MPPT charging, constant voltage equalizing charging and constant voltage floating charging stage.

PWM technology is mature, the circuit is simple and reliable, the price is low, but the utilization rate of components is low. The utilization rate of the module is about 70%; MPPT solar controller refers to the solar controller with the maximum power point tracking function. There is a buck circuit between the module and the battery, and the utilization rate of the module is about 90%.

For PWM controllers, check out https://www.newpowa.com/collections/pwm 

For MPPT controllers, go to https://www.newpowa.com/collections/mppt