MPPT solar charge controller introduction video
MPPT solar charge controller introduction videoMPPT has in many ways revolutionized the PV industry. Higher-voltage PV arrays can now be used, reducing wire cost, improving efficiency, and increasing array performance under less-than-ideal conditions (clouds, low-horizon sunlight). But what exactly is MPPT, and how does it work?Take a 12 V PV module, put it out in the sun, and measure the open-circuit voltage (Voc)—it will be much higher than 12 V, likely approaching 20 V. The reason that “12 V” nominal modules need to produce more than 12 V is that its voltage is the electrical “pressure” in a circuit, and has to be higher than the battery voltage to “push” energy into those batteries. PV modules perform best at cold temperatures, but their voltage will decrease as they get warmer—by about 0.5% per degree centigrade. A “12 V” nominal battery will rise to more than 14 V as the batteries approach a full state of charge. Higher PV voltage is essential, especially in hot weather; to push amps into the battery.