Designing my own Rectifier/Regulator

[Nerobro]

Don't let us distract you. If you need anything yelp. I'll be watching the thread.

 

[cberkeley]

Don't let us distract you. If you need anything yelp. I'll be watching the thread.

I'm not afraid to yell H E L P!.... when necessary. Thanks, I do appreciate all the interest this is generating though.
I just hope this Damned thing works[-o<
Cletus:-D

 

[rustybronco]

my vote 14.2v initial setting, just an opinion.

 

[Nerobro]

These things to stupidly simple NOT to work. i'm willing to bet the total component count in the R/R's we have is... seven? The old brittish bikes used to use a rectifier and a big ziener diode for their electrical needs. I'll bet the stuff in the plastic under ours isn't any more complex.

 

[cberkeley]

Here's a view of the prototype. It will be fitted to the bike this weekend for dynamic testing.
Features:
1) Robust, 40-Amperes, 200V Capacity.
2) Built-in Filter, may be run with a disconnected battery.
3) Adjustable charge rate.
4) All three phases regulated.

View attachment 608

 

[Planecrazy]

Looking good, Pal!!

 

[Boondocks]

Good work! It looks like a nice, clean setup. Keep us advised.

 

[cberkeley]

Seven wires connect it up:
3 Grey - Stator
Black - Battery Negative
Green - Bike Frame Ground (Negative)
Red - Battery Positive
Blue - (Sense) Switched Positive (tail-light or such)
The chassis also is at Negative potential
Once the ignition is on, the red LED should flash, this indicates that the unit is sensing a current. It then quietly does its thing.

 

[tfb]

This is lookin' good, I think I know where my next RR is coming from... ;-)
A couple of questions:
1. Will you fill it with epoxy resin and pop some cooling fins on it somewhere, or do you think it will cope OK 'as is' on the heat side of things?
2. Adjustable charge rate is a handy feature -- but how is it adjusted?

Cheers,
Mike.

 

[Nerobro]

Here's a view of the prototype. It will be fitted to the bike this weekend for dynamic testing.
Features:
1) Robust, 40-Amperes, 200V Capacity.
2) Built-in Filter, may be run with a disconnected battery.
3) Adjustable charge rate.
4) All three phases regulated.

So I see the cap that allows it to run without the battery. Nice Touch. I see Two of the rectifiers right at the top there. The stud mounted SCR's stand out as well.

*grins* nice job.

 

[cberkeley]

This is lookin' good, I think I know where my next RR is coming from... ;-)
A couple of questions:
1. Will you fill it with epoxy resin and pop some cooling fins on it somewhere, or do you think it will cope OK 'as is' on the heat side of things?
2. Adjustable charge rate is a handy feature -- but how is it adjusted?

Cheers,
Mike.

I like to keep my products repairable, so no Epoxy filling. However, to deal with vibration issues when installed on the bike and to keep mounting simple, black silicone RTV will be used between the components on the PCB to dampen vibration and provide isolation and to mount the PCB and cap to the case.
I am hoping the large case 4" x 4" x 1.75" and "overkill" components will keep the temperatures in-check.
There's a 0.25" threaded hole at the side (next to LED) into which a very short bolt with a rubber washer is screwed. Removal of this bolt (keeps out dust and water.... BTW the case is watertight) reveals a screwdriver adjustment for the charge rate. The charge-rate adjustment is a multi-turn adjustment (15-turn potentiometer) this provides accurate and fine adjustment and also negates the need to "seal" the pot against movement by vibration. I may also add a connector for hook-up of a "Battery-Tender"..... but the jury's still out on that one (simple enough though).:-D

 

[beby99]

Excuse my ignorance.....what would be the reason for adjusting the charge rate? Increased output for accessories?

 

[cberkeley]

Excuse my ignorance.....what would be the reason for adjusting the charge rate? Increased output for accessories?

Essentially optimization for your particular bike and battery combination. I've heard many people complain that their lead-acid batteries overcharge and "boil-out" their electrolyte. Various battery types have different charge–rate requirements, Absorptive Glass Mat (AGM) and Gelled Electrolyte Batteries for example may require slightly different charging voltages than do conventional lead-acid types. Not that this is an adjustment that you'd want to twiddle on a daily basis. I envisage, installation on the bike as it comes out of the box and it should work right. However, if a voltmeter, the battery's printed spec or other indication proves otherwise, you're not stuck, you have the option to tweak it into conformity. As I said, I’m an EE with the shop facilities, if I'm going to invest time and resources to this design, I may as well to do it right and try to encompass all the variables. Also, I've heard that folks have run their motor and disconnected their battery, only to have their electronics (Ignitor) fried by the surge and pulsating currents. So, I've incorporated a beefy filter circuit to take care of that eventuality. BTW I have no idea why one would want to disconnect the battery from a running motor??? :?
Design Protocol and Priorities:
1. Build a Rectifier/Regulator package that does not have a tendency to self destruct.
2. One type should fit and work with all PM 3-phase Alternators.
3. Low component count.
4. Multiple Grounding points.
5. Adjustable Charge Rate.
7. Filter Circuit.
8. Battery Tender Jack.

 

[Nerobro]

Also, I've heard that folks have run their motor and disconnected their battery, only to have their electronics (Ignitor) fried by the surge and pulsating currents. So, I've incorporated a beefy filter circuit to take care of that eventuality. BTW I have no idea why one would want to disconnect the battery from a running motor???

Well that's pretty easy to explain. If your battery is T O A S T. that's all youv'e got to run on. I never really viewed it as a problem ;-) I honestly think it's just an old wives tail that your R/R will burn out if you run without a battery. The R/R is under the same load no matter what the state of your battery is.. Itwill dump excess current to the frame no matter what.

 

[cberkeley]

Well that's pretty easy to explain. If your battery is T O A S T. that's all youv'e got to run on. I never really viewed it as a problem ;-) I honestly think it's just an old wives tail that your R/R will burn out if you run without a battery. The R/R is under the same load no matter what the state of your battery is.. Itwill dump excess current to the frame no matter what.

Not sure its an "Old wives tale", let's not forget that the battery serves as a big filter capacitor to smooth out that pulsating DC current that comes out of the rectifier bridge. Depending on the design of the ignitor and other electronics, they may not like pulsating DC. And, if you kill the ignitor you're in deeper crap and still may not get home.

 

[JHawkins]

Have you thought about putting a fuse or circuit breaker on the output side to remove the need for an inline fuse? looks like there would be room left in the case.

 

[cberkeley]

Have you thought about putting a fuse or circuit breaker on the output side to remove the need for an inline fuse? looks like there would be room left in the case.

Good Idea....... Although there's room in the case, I was thinking in-line up under the seat somewhere. My problem with a fuseholder through the case is that it compromises the water-tight enclosure some, unless we go with one of those Marine types.

 

[hungryman]

Cletus,
Good job. If you don't mind might I suggest a switch instead of an adjustable pot. If there are a limited number of discrete battery selections, that is. I've always tried to avoid pots for the end user (in some instances, the spec will specifically state so)> One of those inline selectables might do the trick.

Just a thought. One more q - do you simulate before you prototype, and if so, which one?

 

[cberkeley]

Cletus,
Good job. If you don't mind might I suggest a switch instead of an adjustable pot. If there are a limited number of discrete battery selections, that is. I've always tried to avoid pots for the end user (in some instances, the spec will specifically state so)> One of those inline selectables might do the trick.

Just a thought. One more q - do you simulate before you prototype, and if so, which one?

Switches... not my choice here, I want a "fine tune" of the charge rate. Also, I wanted no moving parts.
I generally design the old fashioned route: sleepless night looking at the ceiling with the idea running around in my head, basic schematic on a paper napkin during breakfast, then I do the rough math during lunch, then I breadboard the thing or parts thereof at about 2:00am when all are asleep, test in the lab and tweak component values, all too often letting out the magic blue smoke while yelling a few choice words of wisedom and starting all over again. I did at one time have a couple of simulation programmes Spice and Electronics Workbench, I like them and still use them sometimes.
BTW the case temperatures are acceptable so far... 40*C over ambient (my ambient is now 29*C) that gives me an operating temp of 89*C Max allowable temp is 150*C ...I think we can get away with the case as is (without fins). Mounting to the frame of the bike will dissipate some addiitional heat too.

 

[mixongw]

Confusing

Confusing

Here's a view of the prototype. It will be fitted to the bike this weekend for dynamic testing.
Features:
1) Robust, 40-Amperes, 200V Capacity.
2) Built-in Filter, may be run with a disconnected battery.
3) Adjustable charge rate.
4) All three phases regulated.

View attachment 608

Where is the third rectifier? How about a schematic? Aren't those bridges?