Faru Baba
6th December 2016, 05:05
Hello!
I'm starting a new project, making wind powered light sculptures. My next step is to make a PMG which I can use to experiment with, but I'm uncertain of how to decide the amount and size of magnets and coils.
Each piece will be erected on 12-16ft scaffolding poles in open fields (10mph winds). They are going to be VAWTs, approx 2mx1m. Each turbine will power a 40W or a 60W bulb at 12V and the light will flux in brightness depending on wind speed and therefore express clearly the power source of the sculpture.
I have been looking at Hugh Piggot's online construction manual for a PMG which uses 16 magnets (20 x 50 x 50) and 6 coils (14AWG, 100 windings) and wire this in star. Looking at the graph on page 5 "power vs speed" this design gives a starting speed at 170RPM and at 240RPM reaches 60W.
https://scoraigwind.com/pmgbooklet/itpmg.pdf
As our maximum output is 60W I thought that this design was slightly over the top and wondered if
a) cutting magnet size (to 10x40x40) and coils respectively to this or
b) omitting one ring of magnets entirely would be a possibility?
I am no engineer and I am coming at this project from an artistic side without ever working with kinetic wind turbines before. So any advice you can give me would really be appreciated!
I'm starting a new project, making wind powered light sculptures. My next step is to make a PMG which I can use to experiment with, but I'm uncertain of how to decide the amount and size of magnets and coils.
Each piece will be erected on 12-16ft scaffolding poles in open fields (10mph winds). They are going to be VAWTs, approx 2mx1m. Each turbine will power a 40W or a 60W bulb at 12V and the light will flux in brightness depending on wind speed and therefore express clearly the power source of the sculpture.
I have been looking at Hugh Piggot's online construction manual for a PMG which uses 16 magnets (20 x 50 x 50) and 6 coils (14AWG, 100 windings) and wire this in star. Looking at the graph on page 5 "power vs speed" this design gives a starting speed at 170RPM and at 240RPM reaches 60W.
https://scoraigwind.com/pmgbooklet/itpmg.pdf
As our maximum output is 60W I thought that this design was slightly over the top and wondered if
a) cutting magnet size (to 10x40x40) and coils respectively to this or
b) omitting one ring of magnets entirely would be a possibility?
I am no engineer and I am coming at this project from an artistic side without ever working with kinetic wind turbines before. So any advice you can give me would really be appreciated!