What to choose PWM (PWM) or MPPT controller? Comment
The operation of power plants using alternative energy sources (solar or wind) is impossible without such an important component as a charge controller – a device that controls the charge and discharge of batteries and is an important intermediate link between solar panels, wind generators and batteries, protecting the battery from overcharging, boiling and discharge below the maximum permissible level.
The service life of the batteries, the volume, quality characteristics of the energy received and, ultimately, the efficiency of solar and wind power plants depend on its operation.
The charge controller is installed between the solar panel and the battery. If the photocells are not exposed to sunlight, the controller is in a “sleeping” state. It begins to function when the voltage from the solar panel reaches certain values (10V in the case of one panel). When the required voltage level is reached, battery charging stops, and when it decreases, it starts again.
Difference between PWM and MPPT controllers
To operate the solar power plant, you can choose a PWM or MPPT controller.
PWM (PWM) controllers
These are simple and, accordingly, inexpensive devices. Their operation is based on pulse-width modulation of the charge current. Controllers of this type can bring the charge level to 100%, without reducing the battery capacity, but their service life is significantly increased.
Advantages of PWM controllers
- Working in automatic mode eliminates the need for additional settings during operation.
- Equipping with modern microprocessors ensures that all parameters are adjusted with maximum accuracy.
- Availability of protection systems against overheating, short circuit, overload, overcharge and reverse current.
MPPT controllers
These are complex electronic devices that provide high precision operation. Using built-in electronics, they can take readings of basic technical operating parameters from solar modules and batteries. The readings are visualized using light indicators or displayed on a liquid crystal display, depending on the controller model.
The operation of these controllers is based on the function of searching for the maximum power point. The device monitors the current and voltage on the solar panels, calculates their ratio and determines the value at which the power will be maximum. At this moment, battery charging begins. At the same time, the controller monitors the charging process, determines the operating modes of energy storage devices (batteries) – accumulation, saturation, equalization and support. This is necessary to determine the current supplied to the battery.
Advantages of MPPT controllers
- Elimination of losses during battery charging.
- Increasing the efficiency of solar panels.
- Good performance in cloudy and cloudy weather.
- Possibility of using high input voltage.
- Possibility of using cables with a smaller cross-section.
- Possibility of location at a considerable distance from the energy source.
- Extending the service life of the battery.
How to choose a charge controller?
Speaking about the difference between PWM and MPPT, it can be noted that PWM controllers are usually installed on low-power solar power plants with a small number of solar panels, while MPPT controllers are more efficient, but are more expensive.
Opportunities of REENERGO company
Don’t have time to figure out which is better MPPT or PWM? Contact REENERGO specialists who will help you select equipment for a solar power plant, tell you about the payback of solar panels and answer all your questions.