I am building this wind turbine project and the problem I am facing is the irregular winds that does not keep the inverters running continuously. I initially decided to solve this problem by employing batteries so that the battery can give continuous output to the inverter as the battery charges whenever the generator spins.

Then I came across Maxwell's Supercapacitor (https://www.maxwell.com/products/ultracapacitors/56v-modules) which is designed to provide power during dips, sags in the main power source. The product description is "Maxwell Technologies’ 56V series of ultracapacitor modules provide power during dips, sags in the main power source. In longer term outages, the modules provide transition/bridge power to a longer term back up source such as a motor-generator or fuel cell. For industrial applications, ultracapacitor modules provide power for graceful shutdown of process equipment." They are designed to fit in standard rack systems with up to 10KW (15 seconds) in 4U height.

I am completely new to these capacitors and I am wondering how to incorporate this into my system. Since it has a very fast discharge time should I use some electronics to control the discharge rate to match he input of the inverter?

Can anyone please explain how this works and how does this go into the wiring diagram?

Thanks in advance!

  • 1
    \$\begingroup\$ What wiring diagram? \$\endgroup\$ – Solar Mike Feb 14 at 6:01
  • \$\begingroup\$ Sorry, I meant to say one-line diagram. \$\endgroup\$ – TheElectrician Feb 18 at 3:01

Comparing super-capacitors and batteries ...

Batteries store much more energy per size/cost/weight than capacitors.

Batteries will handle peaks and dips from 10 minutes to hours, typically.

Capacitors will handle peaks and dips from seconds to minutes, typically.

Capacitors have a larger terminal voltage swing than batteries during the charge discharge cycle, so need wider range converters to best make use of their storage capacity. You generally can't just 'drop them in' to some suitable point on a wind turbine schematic.

Both batteries and supercaps die if overcharged, you need a proper charge controller for either.

  • \$\begingroup\$ Thanks for your great input! The problem I wanted to solve here is to give a smooth and continuous output to the inverter even though the generator's output is irregular due to irregular winds. If I use a 10kW ultra capacitor is it possible to charge it with a charge controller in a small amount of time and regulate the capacitor's discharge speed to make it discharge slowly (like a battery)? Or nothing like this can be done? \$\endgroup\$ – TheElectrician Feb 18 at 3:09
  • \$\begingroup\$ With both batteries and supercaps, you can choose the rate at which you charge them (up to the power output of the source) and can choose the rate at which they're discharged (as long as the load can absorb all the energy you withdraw (like a grid tie inverter), or doesn't demand more than you choose to withdraw (in which case the output voltage will collapse)). \$\endgroup\$ – Neil_UK Feb 18 at 7:03

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