mppt vs pwm
Hi, A nice little video comparing mppt vs pwm with the batteries in bulk mode. mppt vs pwm
Forum Discussion
The MPPT controller buck converter does not use "excess voltage" to make more amps as is usually stated in blurbs. It takes the output power/Vbatt to get amps. The "excess" is in the power the panel can put into the buck converter. The sun is still shining on the panel.
I almost understood that part just above, where the buck converter tries to balance the power at its input with the power being used at its output. It has to find a voltage at the input that will get the power down to what is being used at the output.
So is that still "tracking" or not? It is not tracking for Vmp but it is matching demand by fiddling with voltage. When the battery can accept all the power available, the input to match would have to be optimized, which is at Vmp. When demand is less, it still optimizes voltage but to a different amount. So does it do that the same way?
If so, then we should call MPPT "Voltage Optimizing" and it is always on! We say MPPT stops and is not always "on" and it goes to PWM. It seems all that really means is that it stops finding Vmp but it does not stop finding the optimum voltage at the input. ?????
Oops, so that would mean with enough demand, the optimum voltage could be Vmp, so you would say it is back in MPPT -Bulk. But then what about that 13.2v set point for when it kicks back into MPPT?
It would be a coincidence if V/batt were at 13.2 just when demand got up to where the panel was maxed out. Especially with a big battery bank. It would not necessarily be at a "loaded voltage" that pulled Vbatt that far down.
I almost understood that part just above, where the buck converter tries to balance the power at its input with the power being used at its output. It has to find a voltage at the input that will get the power down to what is being used at the output.
So is that still "tracking" or not? It is not tracking for Vmp but it is matching demand by fiddling with voltage. When the battery can accept all the power available, the input to match would have to be optimized, which is at Vmp. When demand is less, it still optimizes voltage but to a different amount. So does it do that the same way?
If so, then we should call MPPT "Voltage Optimizing" and it is always on! We say MPPT stops and is not always "on" and it goes to PWM. It seems all that really means is that it stops finding Vmp but it does not stop finding the optimum voltage at the input. ?????
Oops, so that would mean with enough demand, the optimum voltage could be Vmp, so you would say it is back in MPPT -Bulk. But then what about that 13.2v set point for when it kicks back into MPPT?
It would be a coincidence if V/batt were at 13.2 just when demand got up to where the panel was maxed out. Especially with a big battery bank. It would not necessarily be at a "loaded voltage" that pulled Vbatt that far down.
