There are two main types of solar regulators (also called solar charge controllers) on the market: solar regulator MPPT and solar regulator MPPT.
PWM- Pulse Width Modulation type solar regulator: It is a current control type, which will switch the input current of the PV array in a PWM pulse mode. When the battery tends to be full, the pulse width will shorten.
MPPT- Maximum Power Tracking type solar regulator. Multiply the voltage U and the current I of the solar cell to obtain the power P, and then judge whether the output power of the solar cell reaches the maximum at this time.If it is not running at the maximum power point, adjust the pulse width, modulate the output duty cycle D, change the charging current, perform real-time sampling again, and make a judgment on whether to change the duty cycle. This optimization process can ensure that the solar cell is always running at Maximum power point to make full use of the output energy of the solar cell array.
Both solar regulators have their own advantages as following:
PWM
The PWM solar regulator is a good low cost solution for small systems only, when solar cell temperature is moderate to high (between 45°C and 75°C)
MPPT
To fully exploit the potential of the MPPT solar regulator, the array voltage should be substantially higher than the battery voltage. The MPPT solar regulator is the solution of choice for higher power systems (because of the lowest overall system cost due to smaller cable cross sectional areas). The MPPT solar regulator will also harvest substantially more power when the solar cell temperature is low (below 45°C), or very high (above 75°C), or when irradiance is very low.
Simple flow chart as follows:
Xindun wholesales solar regulator MPPT and solar regulator PWM for 14 years. For more solar regulator styles, please click here to view.