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How to build a hybrid solar/wind energy harvester?

To smarter battery charging

Each battery(bank) has properties such as voltage and maximum load amperage and It also behaves differently (in our context of energy harvesting) depending on its state of charge (empty, half, full). To charge a battery efficiently and safely the (average) voltage and (average) load current must be measured, filtered and checked continuously. First thing a […]


Dual channel power switching: testing different PWM configurations

Switching power between battery and dump load is an important functionality of a charge controller. Switching fast by means of PWM allows for efficient battery charging: the battery (bank) is charged with an appropriate algorithm (bulk, absorption, float, pulse) while unnecessary energy is diverted to a dump load. Since relays are not well-suited for fast PWM switching, […]


Charging a deep-cycle battery via low-side mosfet switching: the hard way

Introduction The core of our charge controller (PMD2) is essentially two switchable mosfet channels: one channel to load a battery (bank) and another channel to divert abundant energy to a dump load. Both channels can be switched on/off by software controlled PWM, and by configuring different PWM duty cycle ratios, we should be able: to […]