I had a message today from a customer who has 3 turbines from 3 manufacturers. After a few years running he has this observation to make:
I have been very pleased with the PS and its nylon spoons which, even after almost 10 years at 70M head seem barely worn and I’m still on the original bearings. Both the Harris and Stream Engine needed a new runner and bearings.
Stream Engine turgo on left and Harris pelton on right. Note the holes in the Harris runner.
worn stream engine runner
Powerspout AC coupled to the off grid system with a Solis inverter.
Powerspout PLT turbine
corroded magnet rotor on the stream engine turbine
These are both budget systems. Installed since my last post in February.
The first is a low head site in the UK. 160mm PVC drainage pipe works well if properly supported. This one is grid connected using a Ginlong Solis inverter. The “twin pack” is a very cost-effective way to buy a pair or TRG turbines like this with free shipping.
Next is a PLT turbine using 63mm PE pipe for a long 300m run to achieve a 30m head. This one charges a 12V battery using a low cost Tracer MPPT controller, and a Tristar for load management to keep the turbine under load all the time.
It’s great to see photos of turbines up and running, but most times I just have to be happy to hear that everything is going fine.
Nathan Jowett asked me to publish his article that he wrote about his solar hot water system. I have to agree with him that evacuated tubes are brilliant, having had my own system for fifteen years now.
I have written a new report KD 723 which can be copied for free from my website: www.kdwindturbines.nl at the menu KD reports. The title of this report is: “Ideas about an 18-pole, 2-phase permanent magnet generator using the housing of a 6-pole asynchronous motor frame size 100 for driving a 0.55 kW motor of a centrifugal pump”. In chapter 6, an alternative 6-pole armature is described which can be used in combination with the standard 6-pole, 3-phase winding.
“Report KD 718 can be copied for free from my website: www.kdwindturbines.nl at the men KD-reports. The title of this report is: “Ideas about a 16-pole, 3-phase permanent magnet generator using the housing and winding of a 4-pole asynchronous motor frame size 100”.
This report describes a way how to modify a standard 4-pole, 3-phase asynchronous motor such that it can be used as a PM-generator for a wind turbine for 24 V or 48 V battery charging. Manufacture of the new armature is rather easy as the magnet grooves are wide and shallow and in parallel to the armature axis. The magnet costs are low as only a rather small magnet volume is used. Mechanically the armature has sixteen poles but physically it has four poles and therefore it can work together with the standard winding of a 4-pole motor. The flow pattern is given in figure 2. The armature pole angle is 2.5° larger than twice the stator pole angle and the fluctuation of the sticking torque is therefore almost flattened. A front and a side view of the armature and the stator is given in figure 1.
Bear in mind that the turbines are freshly installed and working so the setup is a bit rough in some cases. Most owners will do a bit more work around and about or even build a shed although this is not necessary for protection against the rain. These turbines happen to all be in the British Isles.
Most of my sales are to people who do the work themselves, so I spend plenty of time explaining stuff. I love it. Especially when I get to see pictures.
“Dear Hugh I have added a new chapter 9 in my public report KD 341 which may interest you. The title of this chapter 9 is: “Voltage generation in a coil”. This chapter also contains three pictures of a small 8-pole axial flux PM-generator which show how you go from the ideal coil shape to a shape which is easier to manufacture and contains more copper. KD 341 can be copied for free from my website: www.kdwindturbines.nl at the menu KD-reports. Adriaan Kragten”
It’s comforting to see that the coil shape arrived (below) at is similar to the ones I use in the F- series alternator designs, where I pack in the maximum number of ferrite magnets into the disk. With my Recipe designs for NdFeB magnets I used larger disks relatively and therefore a different coil shape.