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Green Designs…
Enthusiasts and would-be users living in remote locations have a need for “Green” electronics in order to interface their energy sources to storage devices. The energy sources can be water paddle wheels or turbines, or wind driven turbines. Energy production by any of these means is all about efficiency… from start to finish. At the start, there is that design of a turbine for best mechanical coupling to wind or water. With water, there may be the possibility of regulating the power supply at source using a dam and sluice. With wind, the prospect is more challenging. A wind turbine must turn to face incident currents, and cope with a variety of flow rates. The first issue is dealt with by mounting turbine and generator on a bearing controlled by a weather vane. First problem with this is that power has to be transferred across the bearing…typically you would use “slip rings” to achieve this. The second issue is to do with the variability of the energy (wind) supply…here’s where electronics comes in. Small-scale users often opt for a turbine’s energy to be carried to a battery system. This performs a pretty good mating between the variable demand of the user and the variable supply of the wind. So what is the problem???
- Batteries require either constant voltage or constant current charging. These requirements place constraints upon the energy input that the batteries “see”.
- If the battery load is “seen” by the turbine during low wind power situations, the turbine may never have a chance to overcome resting inertia and start turning…so that part of it’s potential output energy profile is lost.
- If the load is too excessive at the start (i.e. if the battery is discharged) it may make unreasonable demands on the generator until it regains a reasonable level of charge.
- Most users want a cheap solution…they make an arguable mistake of looking at set-up cost rather than cost of ownership.
- Generators output variable voltages and currents, which are not ideal for charging batteries.
- The user may be drawing energy short term from the system, quite often faster than the generator can supply it.
So then broad strokes of the design issue are that the systems have to be matched as well as possible and “protected” from each other’s excesses!!! And do all this without wasting that precious energy.
How to implement a solution..
- With a “simple” switch-mode regulator design tailored to the application.
- With a more sophisticated design with built in intelligence (micro controller)
- Do 1 and 2 above for both CV (lead-acid batteries) and CI (Nickel-metal-Hydride) technologies.
Coast Electronics offer electronic regulation devices that fulfil all 4 of the above requirements. Contact us for details, outlining you application (cos we need to know how much power, voltage, type of battery et etc)
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