Greetings, I started a VAWT project. I have fabricated a Stratum PMA and I now I have started a working on a MPPT controller. The VAWT was fabricated to demonstrate the fabrication method. I was looking for away to reduce the internal resistance of the stators on a PMA and I found by stacking the and rotors and connecting the stators in parallel does reduce the internal resistance and does lower the required cut in RPM. During road testing the best the system would produce was 9 amps at 40 MPH wind speed using a 12 volt deep cell as a load. I recently watched some videos on youtude that used a MPPT circuit with a PMA to improve performance. The core of a MPPT circuit is a buck converter. I have made a buck converter and have tested the circuit with my PMA . Manually operating the PMA I was able to produce 4 amps using a 50 watt 12 volt halogen light as a load. Without using the buck converter required a 30 MPH wind speed to produce the same results for my system. I am currently hard wiring the circuit so I can road test the system using the buck converter. I will post results when available, comments welcome.
Hi, You've done some great work on your latest VAWT, I was just checking out your extensive fabrication work and testing over at Fieldlines the other day. (Great to see your post here)! You have a knack for the aesthetics as well as thinking/ creating a bit "outside the box" on this project. I'd be interested in learning more regarding your fabrication process (e.g. materials used, machining techniques etc.) as well as seeing test results. I think you are on the right track by incorporating MPPT to make the best use of power produced, which is already impressive. I find VAWTs fascinating. One of my all time favorites to date is, of course, the Lenz2 (one of Ed Lenz's creations). I enjoyed following his research using lift and drag and even incorporating the venturi effect into his testing. I agree with the conventional wisdom that HAWTs are more efficient (under ideal, clear/ unobstructed airflow situations) however am pleased to see the use of VAWTs explored where HAWTs do not function well (i.e. areas where turbulence prevails, wind directions often change or gusts as well as lower wind speeds are present). Aesthetics, IMO, have a particular value as well, especially in dealing with the acceptance of placing wind turbines within urban areas. I live rural but due to the close proximity of trees, nearby mountain ranges and gorge cliffs the airflows here are quite atypical ... so a VAWT may be a better choice here as well. Will we also see your research delve into lift as well as drag type VAWTs (or a hybrid of the two perhaps) possibly incorporating fractal surface textures (reducing vortices), use of venturi effect ...? Thanks for posting, it will be interesting seeing where your research takes us.
Hi, basically I have tried to include as many adjustable variables as possible into this project. The size of the PMA can be changed. The blade size can be increased. The input output ratio of the transmission can be altered or even removed. Inspiration has been provided from all the other projects that have been posted on other forums. Adding a MPPT controller to any project; VAWT or HAWT; at this time appears to offer the greatest chance for success for having a working project. The blade design is a C rotor. I found using more than three blades made a great difference. The C rotor is easy to fabricate from low cost materials. The blades are attached using a hinge with removable pin. It makes assembly very fast and is very stable. Due to time, available resources, and my limited knowledge I am unable to address your other questions. They are intriguing and hopefully someone with more experience and resources will be able to answer them. Hard wiring the perf-board circuit is proving to be more challenging then first anticipated. I hope to be testing again in a few days. I will post results when available.
Hi, I completed fabrication of analog MPPT test circuit. Video shows verification of selectable duty cycle with fine adjustment of each for each selected duty cycle, 10% to 50%. Next step is to test with PMA and battery test load. I am hoping I did not damage the mosfets when I solder them in the circuit.
