The solar controller is a device placed between the solar panel and the battery pack to control the electric energy generated by the solar panel entering the battery. The main function is to ensure that the battery is properly charged and prevent overcharging. There is no better pwm or mppt solar controller, and the choice depends on personal needs.
If you plan to install an off grid solar system with a battery pack, you need a solar charging controller.
At present, two types of charging controllers are commonly used in PV power systems:
1. Pulse Width Modulation (PWM) controller and
2. Maximum Power Point Tracking (MPPT) controller.
PWM solar controller:
PWM, namely pulse width modulation, is used to adjust the charge. Its function is to pull down the voltage of the solar cell array to the voltage close to the battery to ensure that the battery has been correctly charged.
It uses an electronic switch (MOSFET) to connect and disconnect the solar panel from the battery. By switching MOSFETs at high frequencies with various pulse widths, a constant voltage can be maintained. The PWM controller adjusts itself by changing the width (length) and frequency of the pulses sent to the battery.
PWM controller is more suitable for small solar energy system. It provides a low-cost solution that is typically used when the solar cell temperature is between 45 ° C and 75 ° C.
MPPT solar controller:
The MPPT charging controller extracts the maximum power from the PV module by forcing the PV module to operate at a voltage close to the maximum power point. It is designed to adjust its input voltage to take advantage of the maximum power output of the solar array, and then convert this power to provide varying voltage requirements. The input voltage is changed by using a DC/DC converter.
The MPPT controller does this through an adaptive algorithm that follows the maximum power point of the solar panel/array and then adjusts the input voltage to maintain the most effective power of the system.
When the solar cell temperature is low (below 45 ° C), the performance advantage of MPPT controller is very obvious. They are more efficient than PWM controllers. MPPT controller is the best solution for high power system.
