The main difference between PWM and MPPT charge controllers is how they track a solar panel’s maximum power point (MPP).
- PWM (Pulse Width Modulation) charge controllers use a simple method of charging a battery by switching the current on and off at a very high frequency. This method is relatively inexpensive and easy to implement but less efficient than MPPT controllers. PWM controllers also have a lower voltage range than MPPT controllers, which can limit their use in some applications.
- MPPT (Maximum Power Point Tracking) charge controllers use a more advanced method of tracking the MPP of a solar panel. This method involves constantly adjusting the voltage and current output of the controller to ensure that the panel is always operating at its maximum power point. MPPT controllers are more efficient than PWM controllers and can be used with a wider range of solar panels.
- Maximum Power Point Tracking, frequently referred to as MPPT is an electronic system that operates the Photovoltaic (PV) modules in a manner that allows the modules to produce all the power they are capable of. MPPT is not a mechanical tracking system that physically moves the modules to make them point more directly at the sun. MPPT is a fully electronic system that varies the electrical operating point of the modules to deliver maximum available power.
solar panel graph
MPPT charge controllers are generally the better choice for most solar applications. They are more efficient, can be used with a wider range of solar panels, and can provide a longer lifespan for your battery. However, MPPT controllers are also more expensive than PWM controllers.https://suvastika.com/whats-pwm-solar-charge-controller/
There are important features which should be there in the MPPT charge controller to give a better performance, like Four Stage Battery Charging Processes (Bulk, Absorption, Float, Equalization) and ATC (Automatic Temperature compensation) for the temperature change to be compensated while charging through the Solar panels.
Also, these Protection Against
Reverse Battery Connection
Surge Protection
Ambient Temperature Compensation
Heat Sink Temperature Compensation
Reverse Battery Current Flow Protection
PV High Current Protection
Overload and Short Circuit Protection
Here are some factors to consider when choosing between a PWM and MPPT charge controller:
- The size of your solar system: A PWM charge controller may be sufficient if you have a small solar system. However, an MPPT charge controller will be more efficient if you have a larger solar system, and the cost of Solar panels Vs an MPPT charge controller can be compared. There will be great savings in cost as the bigger the system higher the savings in cost if we use MPPT solar charge controller compare to the PWM solar charge controller.
- The type of solar panels you have: If solar panels have a high maximum power voltage (Vmp), an MPPT charge controller can extract power from your panels.
- Your budget: PWM charge controllers are less expensive than MPPT charge controllers. However, the extra cost of an MPPT charge controller may be worth it if you have a large solar system or want to maximise your solar panels’ power output.https://en.wikipedia.org/wiki/Charge_controller