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[VAWT] First practical tests

The first practical tests have commenced! The windmill below is built within this Bachelors Thesis: 

We had worked in small subgroups, where I had focused on calculations, software and electronics. Some other guys had done the mechanical design and therefore I didnt't see the turbine first until the day all parts were to be assembled. What I hadn't realised before is that the turbine is huge! It measures some above 3 meter in height. Here is a rather crappy first movie of over first test run:

 Turbine control is done via electronic switching by using PWM. A Maximum Power Point tracking algorithm is tried here. Among other things wind and electrical output (voltage and current) are measured that can be used to evaluate system performance. This can be used for estimating turbine output.

The current measurement was bit of a challenge to design as it had to work over the unusually large range 0,5- 60 amps. The measurement is split up in to ranges in hardware in this design. Here is what the designed circuit looks like from below:

For simplier interfacing I created a graphic interace using Qt C++. It uses serial communication (UART) and a self designed protocol for changing parameters during runtime, interfacing with the SD-log on the control unit, read strings sent via UART and live plot of values.  When a bluetTooth serial modem is used this can be done wireless which is very neat.  The interface looks something like this:

I choose to call it SavoniusView.


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[VAWT] Affordable wind measurements

The shop Clas Ohlsson in Sweden sells a spare anemometer for the  WH-1080 weather station for a hobbyist friendly price around 15 euros. This anemometer can probably be found in other countries too.

The WH-1080 spare anemometer

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Guide: Get more distortion from an HCM65R amp

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