Q&A Forum
Ok ...... maybe until confirmation of the above, I'll ask a supplemental question that someone might help with :
I'm under the impression, rightly or wrongly, that the link component between the 'Eddy Current power control driver' discussed above and the 'YourDyno blue control box', namely the 'Optocoupler' (breadboard circuit), due to it's intrinsic design affords a margin of isolation therefore protection to the 'YD bcb' ?
Being an 'optical' device, feedback (spikes etc) form the 'EC pcd' back into the 'YD bcb' is inhibited or prevented ?
TIA, John
Right ..... and apologies for this ...... for those that may be interested :
The capacitor value is 0.1 uf according to the HP HCPL 3120 data sheet, which concurs with the above
It gives you the calcs to determine the gate resistor value, but .......
...... browsing the Mitsu IGBT data sheet it's simply stated as 3.1 ohms, which concurs with the above
So that answers that, lol, unless someone's got something to add ...... 🤪
Subscribe with interest to this thread ! So you're building the whole lot ?
Mach_1 ..... yes thanks, unfortunately I'll probably be around for a while, lol
My own idea for a hub dyno goes back some years, I've had the Telmas more than fifteen, 'bout time I did something with 'em ....... you could pick them up for pennies back then
There's a nice Aus built one on YT, pretty much how I envisaged the job all along but with a few alterations ..... so mine might look a bit like a 'copy' when it's been sketched out for a while now
'Rear' axle will be hybrid CC160s, then following that 'front' will be CC80s, once I've obtained the second one
I'll be doing everything except Josteins bit hopefully, spare EC drives on hand etc ...... I like to fix my own stuff when it goes wrong if nothing else
The capability to couple the two axles (four brakes) from one controller would be nice ..... I've seen the latest YD box now controls 4 brakes / 2 rpm but don't think that's across two axles ?
I've a 'new' Froude AG150 to do then, replacing the old Texel control, and then an ancient G4 once I've got a better handle on the whole deal
It'll keep me out the pub, if nothing else ....... 😀
Sounds like your a Ozztralian ? " Pub " ?
No mate ....... not a colonial ......
Not that you can 'go down the pub' at the moment ennyhoo ....... lol 🤪
LOL ...... I'M sure once the queen of Great Britain stop living Australia will breakaway from her clutches and become a free country.
Curiously what country are you from ?
English, mate ...... not that it matters much in this wonderful global collective that allows a resource such as this .......
Anyway, most of the parts are either with me on or on order, so once I've freed myself up a little, I'll crack on
One of the first jobs is to disassemble, test, 'blueprint' (for want of a better term), reduce the tolerance stack, and rebuild the Telmas
One's a CC135 and t'other a CC160 ...... plan is to hopefully get them up to around 1800nm apiece
Good discussion! A few answers:
I'm under the impression, rightly or wrongly, that the link component between the 'Eddy Current power control driver' discussed above and the 'YourDyno blue control box', namely the 'Optocoupler' (breadboard circuit), due to it's intrinsic design affords a margin of isolation therefore protection to the 'YD bcb' ?
You need a driver for the gate of the IGBT transistor. The optocoupler isolates YourDyno from the power, which is good since there are large currents involved and you may not have the same ground potential as YourDyno.
The CM200DY-12H has two transistors each with a flyback diode included. Transistor 1 is off (by shorting G1 and E1), but its flyback diode is important. It is used to provide a path for the current when Transistor 2 turns off.
An improvement to the circuit is to add a power resistor in series with the diode. This makes the stored energy burn off quicker, thus enabling the current (brake torque) to be reduced quicker. This is not possible with the CM200Y-12H since the two transistors are mounted back to back. You can choose a single IGBT and a single Diode then you have that opportunity. Make sure to size it properly in terms of its ability to absorb energy.
If you like to play with these things, I recommend LTSpice!
Nice to follow your progress, keep us posted!
An improvement to the circuit is to add a power resistor in series with the diode. This makes the stored energy burn off quicker, thus enabling the current (brake torque) to be reduced quicker. This is not possible with the CM200Y-12H since the two transistors are mounted back to back. You can choose a single IGBT and a single Diode then you have that opportunity. Make sure to size it properly in terms of its ability to absorb energy.
Do you /anyone have a circuit diagram for that ?
I'm 'belt and braces' so tend to overbuild everything ..... the IGBT / Bridge I'm building has a power factor of 3+ over the amp draw of the soaked Telma
Jostein ...... are there any plans to release a YD box that controls four brakes over two axles ? Linux .... lol ?
Hi,
4 brakes are already supported :-)! Need 2 YourDyno boxes, one for each axel.
See this circuit diagram. Don't pay attention to the exact component part numbers, those need to be selected carefully.
I did some simulations now. This circuit is quite fast, even without a resistor. The simulation attached is with a Telma CC160.
If you want to add a resistor, put it in series with the diode.
4 brakes are already supported :-)! Need 2 YourDyno boxes, one for each axel.
Jostein, yes thanks, from reading an earlier thread I was aware of that ...... is it possible to sync the two boxes via the software to come up with a single output ?
See this circuit diagram. Don't pay attention to the exact component part numbers, those need to be selected carefully.
I did some simulations now. This circuit is quite fast, even without a resistor. The simulation attached is with a Telma CC160.
If you want to add a resistor, put it in series with the diode.
Excellent, thanks .....
'selected carefully' : Does that mean they can be simply overrated or have to be carefully 'sized' ?
If desired, how would you determine the value of the resistor ?
The data sheet of the R6020PNJ shows the gate voltage as +30v- ...... I assume these are maximum values and that 5v would drive it ?
Or would you still drive the gate via the optocoupler circuit discussed prior (15v), thus retaining the preferred isolation characteristics ? If so, would the gate resistor still be 3.1ohm ...... if not how would you determine the value ?
Apologies for all the questions, I'm guessing you're quite busy anyway, but I would imagine a proven home built eddy current brake power drive system, using relatively up to date components, would be of interest to a fair few people constructing their own systems ......
All the best ...... John
'selected carefully' : Does that mean they can be simply overrated or have to be carefully 'sized' ?
What I meant is that the components used in that simulation is just for a quick general test, they will not work in real life, because they are not rated for the power and voltages. The simulation still works well.
Here is a good document to study if you want to learn about IGBT designs:
You cannot drive the gate with 5V, you need much more, typically 15V. That (plus isolation) is why there is a gate driver in the circuit.