Looking for ways to combine the power outputs of different renewable energy sources

Question

I've been researching ways of combining the outputs of different renewable energy sources (e.g. solar panels and DC rectified wind turbines) to provide a single output that could then be connected to a charge controller.

I've started with two theoretical sources in parallel, each with approximately the same voltage but potentially different maximum wattage outputs and probably different I-V curves.

These sources would also be operating independently e.g. one could be running at maximum capacity while the other was idle.

From my research so far - including helpful answers here on EE.SE - it seems there are potentially two methods (1) and (2) in the diagram below. The first uses two diodes in what I believe is an OR combination and the second uses a dedicated charge controller for each source output.

My question: Are there any other options for achieving this that might offer an improvement over two diodes but without the increased cost, size and weight of multiple PWM/MPPT chargers?

Initially I imagined/assumed some sort of 'current summing circuit' - but so far I've not found anything suitable.

If the potential solution was based on an active circuit - it would need to run off the battery it was charging.

Answer 1

You will need different strategies for combining multiple inputs of the same type vs. different types.

If you are combining two PV arrays, as shown, then the diodes (blocking diodes) will work fine, and may even be optional when feeding into a single MPPT unit. If the arrays are very different in voltage (number of cells in series), however, then you will need multiple DC/DC converters.