Charge Controllers PWM Vs MPPT

PWM Vs MPPT

Charge Controllers are the devices which control the input Voltage and current.The applications vary from Solar, Wind or  UPS backup systems etc.These Charge controllers are introduced due to a specific purpose that is to restrict the unwanted spikes in current or voltages to a Battery or other devices so as to protect the Battery from damage.

There are types of Charge Controllers mainly PWM vs MPPT.The PWM(Pulse Width Modulation) is the oldest way of controlling the I-V characteristics and the later is the MPPT(Maximum Power Point Tracking) is the newest addition to improving the battery life.

If the Solar Panel Output cannot be controlled then the battery connected without charge controller will get damage due to uneven output and there is a chance of overcharging that leads to the blasting of battery in extreme cases.

What is PWM Charge Controller?

                                 

PWM refers to Pulse Width Modulation Charge Controller, is a tested and old technology for charging Batteries.The PWM works by matching the battery Voltage by Pulling down the Panel Voltage.

Consider a 100W,12V Solar Panel; At Peak Hour the Solar Panel can produce approx 18V Output Voltage and 5.6A Current Which equals 100.8W.

Consider we have to charge 1 No of 12V & 20AH Battery, then the PWM will bring down the Panel Voltage from 18V to 12V to charge the battery, so 6V is getting Wasted and also the power received by the battery is to be 67.2, not 100W.Thus the efficiency of PWM is Less.

But it is one of the cheap and best charge controller to protect the battery from overcharging.Consider buying Charge Controllers according to your need and Cost for example for cold climates PWM is best suitable than MPPT.

What are MPPT Charge Controllers?

                                    

MPPT refers to Maximum Power Point Tracking Charge Controllers which is the new technology developed to increase the efficiency for charging the battery and it works by tracking the maximum power(I-V) at Δt.Unlike PWM the MPPT controller does chop the Voltage but the same proportion of Current will be brought up so as to maintain the output power level.

For Example:

Consider a 100W,12V Solar Panel; At Peak Hour the Solar Panel can produce approx 18V Output Voltage and 5.6A Current Which equals 100.8W.

Consider we have to charge 1 No of 12V & 20AH Battery, then the MPPT will bring down the Panel Voltage from 18V to 12V to charge the battery and also increase the Current level to 8.4A to maintain the power level of 100W.Thus no power loss.