HA-4 our first 3 Phase Turbine
Front view showing water pump bearing
From design to construction
by Chris (Techie) & John (Donkey) the story of our 3 phase PMG turbines from HA-4 to our latest the HA-6 3FP
After more research and dogged determination in mounting the Rotor/Stator from Chris HA-4 was launched, our first 3 phase 3 blade PMG turbine with wooden carved blades.
Only someone who has attempted to mount a rotor containing several magnets around a laminated core stator and keep .5mm equal clearance can begin to understand the frustration. I left for work one Saturday morning having spent several nights failing to get it together satisfactorily, in truth I had decided to give up. On arrival home that night Christopher asked me if I would weld something for him. On arriving in the workshop I was absolutely amazed to see the rotor revolving, he had spent the entire day positioning then tacking with welder to find it wasn't right, then cutting off and repeating the progess endless times. In hindsight we were torturing ourselves and HA-5 when it was born mounted on a tailor made shaft was a much better solution.
by Chris (Techie) & John (Donkey) the story of our 3 phase PMG turbines from HA-4 to our latest the HA-6 3FP
After more research and dogged determination in mounting the Rotor/Stator from Chris HA-4 was launched, our first 3 phase 3 blade PMG turbine with wooden carved blades.
Only someone who has attempted to mount a rotor containing several magnets around a laminated core stator and keep .5mm equal clearance can begin to understand the frustration. I left for work one Saturday morning having spent several nights failing to get it together satisfactorily, in truth I had decided to give up. On arrival home that night Christopher asked me if I would weld something for him. On arriving in the workshop I was absolutely amazed to see the rotor revolving, he had spent the entire day positioning then tacking with welder to find it wasn't right, then cutting off and repeating the progess endless times. In hindsight we were torturing ourselves and HA-5 when it was born mounted on a tailor made shaft was a much better solution.
The Detail
This turbine which had a strange box section frame worked after a fashion, all be it on direct drive, as we had no batteries for storage. Output was good enough to power 12v bulbs and with some home made reflectors gave reasonable light. An old Volvo car water pump was the bearing used to support the generator shaft (well it was suitable for wet weather use).
This machine evolved into HA-4 MkII and eventually MkIII with different blades and Tip Speed ratios. At last we had battery backup ( old tractor battery ) and I used it for lambing ewes and lighting the cattle shed. Mounted on a shed roof at the back of the yard it never got clean air from any direction although it was mechanically reliable, but not very efficient.
The permanent magnets on the rotor meant no brushes to worry about as the stator as its name suggests wasn't revolving. Voltage loss on the 12 volt lighting circuit was big. A New rectifier had to be made, this time we were rectifying 3 phase to DC to charge the battery. This was made by using 6 diodes see Fig 1.
Like all its predecessors it had no slip rings the cable simply dropped down the inside of the pole exiting above ground level.
Around this time I was reported to have been seen watching Coronation Street on a portable TV in the lean-to ( the one and only time ) from power supplied by our own wind-turbine.
On one occasion it became a "Runaway" blowing all the bulbs we had attached.
After a period of a couple of years a decision was made to make a new machine HA 5 which could be closed down on stormy nights to avoid any further chance of a "Runaway".
Estimated output from HA-4 was around 40 watt in a 15 mph wind, but on occasions at very high revs peaked at over 150 watt. Sorry no Rated Output, Techie was still only a kid and figures weren't something I was worried about then, just get them darn bulbs to light!
Cost in the region of £8.00 - £10.00 + Endless Hours on cold winter nights = Great satisfaction when the light came on.
This machine evolved into HA-4 MkII and eventually MkIII with different blades and Tip Speed ratios. At last we had battery backup ( old tractor battery ) and I used it for lambing ewes and lighting the cattle shed. Mounted on a shed roof at the back of the yard it never got clean air from any direction although it was mechanically reliable, but not very efficient.
The permanent magnets on the rotor meant no brushes to worry about as the stator as its name suggests wasn't revolving. Voltage loss on the 12 volt lighting circuit was big. A New rectifier had to be made, this time we were rectifying 3 phase to DC to charge the battery. This was made by using 6 diodes see Fig 1.
Like all its predecessors it had no slip rings the cable simply dropped down the inside of the pole exiting above ground level.
Around this time I was reported to have been seen watching Coronation Street on a portable TV in the lean-to ( the one and only time ) from power supplied by our own wind-turbine.
On one occasion it became a "Runaway" blowing all the bulbs we had attached.
After a period of a couple of years a decision was made to make a new machine HA 5 which could be closed down on stormy nights to avoid any further chance of a "Runaway".
Estimated output from HA-4 was around 40 watt in a 15 mph wind, but on occasions at very high revs peaked at over 150 watt. Sorry no Rated Output, Techie was still only a kid and figures weren't something I was worried about then, just get them darn bulbs to light!
Cost in the region of £8.00 - £10.00 + Endless Hours on cold winter nights = Great satisfaction when the light came on.