mppt vs pwm
Hi, A nice little video comparing mppt vs pwm with the batteries in bulk mode. mppt vs pwm
Forum Discussion
With mppt, other than in low light conditions, I cannot imagine battery voltage ever getting even close to panel voltage. So, low lighting conditions aside, during normal operation, a good mppt controller should buck voltage down to the necessary voltage to charge the batteries, until such time as Vbatt reaches the Voltage Setpoint, correct? At this time, voltage would be held at the setpoint, and amps would begin to taper in Abs/cv?
I asked the (initial) question, regarding mppt functioning continually throughout, because some folks operate/cycle their batteries in the 50-80% range, while others keep their bank up in the 85-100% range. With solar, I imagine most operate in the upper soc range. So I'm wondering if this could affect maximum power tracking? In other words, can one think of solar in terms of charging with a charger?
For example, using a charger, a C/5 charge rate would keep the bank in bulk stage up to say 85% soc (I see 83% at a C/4.8 rate, so this a reasonable estimate). A 400Ah bank would require 80 amps for a C/5 rate. Once the Voltage Setpoint is reached, amps would begin to taper. So, if starting at 85% soc, the 80 amp charger would go into abs mode very soon after starting.
Likewise, 1100-1200 watts of solar could supply 80 amps, using mppt. So, if starting from an 85% soc, it seems the bucking feature of an mppt would not function for very long. But can one make such a comparison, or does panel voltage throw a wrench into trying to compare the two? (mppt vs a charger, not mppt vs. pwm)
I asked the (initial) question, regarding mppt functioning continually throughout, because some folks operate/cycle their batteries in the 50-80% range, while others keep their bank up in the 85-100% range. With solar, I imagine most operate in the upper soc range. So I'm wondering if this could affect maximum power tracking? In other words, can one think of solar in terms of charging with a charger?
For example, using a charger, a C/5 charge rate would keep the bank in bulk stage up to say 85% soc (I see 83% at a C/4.8 rate, so this a reasonable estimate). A 400Ah bank would require 80 amps for a C/5 rate. Once the Voltage Setpoint is reached, amps would begin to taper. So, if starting at 85% soc, the 80 amp charger would go into abs mode very soon after starting.
Likewise, 1100-1200 watts of solar could supply 80 amps, using mppt. So, if starting from an 85% soc, it seems the bucking feature of an mppt would not function for very long. But can one make such a comparison, or does panel voltage throw a wrench into trying to compare the two? (mppt vs a charger, not mppt vs. pwm)
