I have a Boron LTE powered by a 5V, 5W solar panel connected to VUSB. I want to use my panel at its maximum power point to get the best charging efficiency.
One idea I had was to dynamically adjust the battery charge rate using
SystemPowerConfiguration::batteryChargeCurrent() so that the panel operates as close to its maximum power point (Vmp) as possible.
The characteristic equation for a solar panel states that output current decreases as voltage increases, in a non linear fashion. Therefore it seems that the panel voltage can be controlled by measuring VUSB: if the voltage is above the Vmp then increase the charging current; if it’s below Vmp then decrease the charging current.
Is doing MPPT in firmware a good approach, or can this be done in hardware with the PMIC?