Search found 103 matches

by bobc
Fri Jan 09, 2009 1:27 pm
Forum: Home Energy Area
Topic: Solar PV array prices in 2009
Replies: 14
Views: 35717

Solar PV array prices in 2009

Just read a "2009 forecast" in a trade rag; apparently there will be massive overproduction of PV arays in 2009 (lots of new manufacturers & recession cutting back capital projects).
Maybe a good time to invest towards the end of the year!
by bobc
Tue Jan 06, 2009 1:18 pm
Forum: General
Topic: 10kW BLDC outrunner drive
Replies: 18
Views: 22528

Some progress, but it's been way too cold to spend time in my shed.... just found this: http://en.wikipedia.org/wiki/Outrunner we were discussing windings on another thread. I'll add a couple of PCB pictures soon, the opto board & slotty wheel are done & I've started on the drive board. Bob
by bobc
Fri Dec 19, 2008 12:41 pm
Forum: Hot off the press....
Topic: Tesla on Top Gear
Replies: 4
Views: 4693

Tesla on Top Gear

Surprised no-one has brought this up yet, the battery car did very well - went like stink & did 55 miles of "track" driving before the batts were flat. The presenters complained it therefore wouldn't go from lands end to john o groats non- stop (after all that's what we'd all use it fo...
by bobc
Sun Nov 23, 2008 8:19 pm
Forum: General
Topic: 10kW BLDC outrunner drive
Replies: 18
Views: 22528

10kW BLDC outrunner drive

So far just plans... I think Jeremy's multi-motor approach is just the thing for a big "secret project" I've started on, but we'll need special electronic drives. Current plan is to make "drive modules" with 4x 2.5kW outrunner motors on a single shaft - so I'll need a 40V 300A co...
by bobc
Sun Nov 23, 2008 7:47 pm
Forum: All things battery related
Topic: Maximum outdoor charging current?
Replies: 12
Views: 14228

Just pointing out a recent "special offer" at ALDI; - external twin 13A slocket with cover, cable glands & an RCD plug - I think it was about 20 notes.
by bobc
Mon Nov 17, 2008 6:35 pm
Forum: General
Topic: PML hi-pa drive motors
Replies: 9
Views: 9145

I've also asked & been told very silly prices indeed. I guess they must be some flavour of brushless DC. I notice siemens (I work for them) are also publicising a "in wheel" motor on their website - but it's all talk so far. I've never been convinced by in-wheel motors - it must compro...
by bobc
Thu Nov 13, 2008 7:24 pm
Forum: General
Topic: Multiple motor & controller approach?
Replies: 87
Views: 62805

Yes Jeremy, but at the end of the shaft all the torque has to end up in the pinion... I was thinking of making a thicker extension shaft at the end for the pinion that could be directly coupled to the nearest outrunner so I only have 3/4 the torque to transmit. Anyway I just noticed a classic cockup...
by bobc
Thu Nov 13, 2008 3:48 pm
Forum: General
Topic: Multiple motor & controller approach?
Replies: 87
Views: 62805

Pertinent factor there is that trantorq specify they achieve 23Nm torque capability onto an 8mm shaft with such a compression fitting.
23Nm @ 7000rpm is 16.8kW !!!!
And 4 of those little motors is just 10kW - safety factor of 1.7, that's good enough for me.....
by bobc
Thu Nov 13, 2008 11:16 am
Forum: General
Topic: Multiple motor & controller approach?
Replies: 87
Views: 62805

OK - I have a plan to improve shaft coupling: the outrunner end has the 4 threaded holes to attach the prop adapter; my plan is to use these to pull a boss onto a split tapered inner (mucho like a taperlok). This should squeeze the shaft enough to do most of the work & use the flats on the shaft...
by bobc
Wed Nov 12, 2008 11:30 pm
Forum: General
Topic: Multiple motor & controller approach?
Replies: 87
Views: 62805

2 motors arrived today. I note that the prop connection is at the turning end of the outrunner & I'm a little concerned about the practicalities of keeping 4 motors in synch on a single 8mm shaft if they're just attached by grubscrews. Basically I'm thinking that a keyed driving collar will have...

Go to advanced search