Author Topic: An Affordable Electric Genset Governor?  (Read 20727 times)

listeroidsusa1

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An Affordable Electric Genset Governor?
« on: September 25, 2007, 02:34:58 AM »
I'm working on an inexpensive throttle governor for the Lister(oid) generators. I have a model bench tested and so far it works great. It has very  good speed regulation and can do away with the original governor. The original governor becomes a mechanical fail safe and actuates the compression release in the event of a fault or over speed condition. If deemed necessary the electronics can also be programmed to actuate a solenoid to activate the compression release and bottom the fuel rack in case of overspeed. I built this out of parts I had from my school junk box. I've ordered a set of production parts to make a run of 25. The price will be $50 or less depending upon volume and circuit board etching. If everything works out ok this will be a great way to control engine speed very precisely, and with only a turn of a rheostat. Factory units are quite expensive but I've built this one on the KISS principle with only the necessary bells and whistles. The tach/generator can be a common small dc motor and the actuator is a simple solenoid operated under pwm control. The governor has adjustable parameters so that any number of used or surplus parts can be matched to the control unit. The negative feedback loop controls the governor down to the millivolt level from the tach/generator. Thats .001 volt, and since the tach/generator signal is proportional to speed it holds as tight a frequency as the engine power pulses allow. The generator/control can sense  and adjust 20K pulses/sec. but the lister may only fire a few times per second so there may be a small lag but it probably won't be noticeable as the circuitry will be all over it if it steps out of bounds at all.

It could be set up another way also, the pwm actuator could be hooked up in tandem with the original governor which is set just below the desired speed and the electronics just "help" it up to speed and control the regulation. This, in theory, would be more of a fail safe option. These are some things I'm testing before selling any. It does look very promising though.! I'm looking at 2 versions, one with at 12v battery/alternator system, and a stand alone version using a small dc motor with a tach/generator to both generate the power to run the pwm throttle solenoid, and to supply power for the control.

I'll post more info in the Market Place when I have a production unit up and running.

rcavictim

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Re: An Affordable Electric Genset Governor?
« Reply #1 on: September 25, 2007, 03:20:33 AM »
From one who understands the kind of R&D that has to go into an idea like this I tip my hat and salute you.  I think this is a marvelous idea and represents a product that certainly is needed!  I`ll follow your updates on this project with interest.
-DIY 1.5L NA VW diesel genset - 9 kW 3-phase. Co-gen, dual  fuel
- 1966, Petter PJ-1, 5 kW air cooled diesel standby lighting plant
-DIY JD175A, minimum fuel research genset.
-Changfa 1115
-6 HP Launtop air cooled diesel
-Want Lister 6/1
-Large DIY VAWT nearing completion

listeroidsusa1

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Re: An Affordable Electric Genset Governor?
« Reply #2 on: October 09, 2007, 12:53:48 AM »
The prototype electronic governor has been built and bench tested. My Darlington transistor sets should arrive this week and will be used to interface the controller to a dc solenoid which will operate the throttle. The system is very sensitive to rpm change and the correction factor will be immediate, controlling the next firing of the injector. I decided to make this as simple an installation as possible and it can be used on any IC engine. Pots will be included to tune the control to any engine dc control voltage from 6-24 vdc, as well as a pot to tune the negative feedback loop.

Your original governor will be set up to control the engine at its no load speed such as 650 rpm, or whatever you want it to run at, eliminating the need for special governor springs to control droop. The control solenoid will connect in parallel with your governor spring and if the electronics sense a lowering of the rpm the solenoid will activate only until the rpm is once again synchronous. When it drops again the cycle will repeat. Remember, this is happening incredibly fast so you probably won't notice the pulsing of the solenoid. The electronics can run for weeks on a 9 volt battery since all it is running is the IC chip and a led for the opto-isolator, (the circuit board is about the size of a quarter) or we can set it up to use a standard 12 volt mower battery. All you'd need is a trickle charger to keep the battery topped off. The battery is primarily for the solenoid load. Its a simple system that will be easy to install and set up. Engine speed changes will be made with a potentiometer and readjusting your stock governor for a baseline setting. The speed sensor is a common dc hobby motor connected to the engine as a tach/generator which will feed the negative feedback loop and keep the electronics within .01% regulation. Since the injector firing is rather slow the overall regulation will be somewhat less but still in a very respectable range, probably 1%. The integrated circuit chip I'm using has a gain of 200,000 and with the opto-isolated Darlington transistor pack it can control many amps of current to the speed solenoid. A similar IC chip can also have 3 other set points for over speed, oil level sensing, temperature, ect. Best of all, the entire system will be less than $50 to install! I should have it running this week. It will be put into operation for a while to verify operation and reliability but it looks very promising.

listeroidsusa1

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Re: An Affordable Electric Genset Governor?
« Reply #3 on: October 09, 2007, 01:33:55 AM »
The electronics work much faster than the engine can droop. The original governor will only provide a base line set point. When installing the solenoid the max fuel setting should only be as much as it takes to carry the maximum load. Setting any of the Lister type engines to the point where they smoke is false economy and also adds greatly to the emissions output. Once the remainder of my parts arrive we'll test out all of the possibilities. The engine speed droop won't be a problem since the controller will activate if the sensor voltage drops even 1 millivolt under the threshold. You're still thinking in terms of mechanical governors and the electronic versions respond hundreds of times faster and are more accurate. An actual running engine will tell the whole story later.

mobile_bob

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Re: An Affordable Electric Genset Governor?
« Reply #4 on: October 09, 2007, 06:38:05 AM »
Mike:

i am very interested in your approach, electronic governors are quite expensive (sometimes nearly as much as what one can spend on
one of these engines when it is fully implimented) so other options are surely welcome.

while the electronic high dollar versions are accurate to within a gnats ass, we don't need that kind of accuracy in my opinion for these
singles and twins (i question the ability of even the high dollar versions to get the advertised accuracy on these engines as well)

in my opinion a governor that can hold plus or minus 1 hz (59 to 61hz) over the load range is more than adequate for the vast majority of
applications, anything tighter than that will likely add significantly to the cost of the unit, and you will reach a point of dimished returns quickly
in my opinion.

it sounds like you are working with an analog type of control rather than a digital design,, personally i think analog is more than adequate if done
right.

if i understand your design, this thing is made to augment the mechanical governor, or rather to bias it? or will it be such
that it will replace the governor and attach to the fuel rack directly?

if it replaces the mechanical governor, i assume there will be a failsafe to shutdown?
so that if it loses tach signal or power the rack closes?
if so will there be an override to provide for opening the rack for startup?

if it works as hoped and you can market it for 50 bucks,, you should have a steady income from the sales of the unit.

and i will buy one too! :)

(personally i think your pricing is too cheap)

good luck

bob g
otherpower.com, microcogen.info, practicalmachinist.com
(useful forums), utterpower.com for all sorts of diy info

listerdiesel

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Re: An Affordable Electric Genset Governor?
« Reply #5 on: October 09, 2007, 07:43:25 AM »

I am a bit confused ... a solenoid is usually an on/off situation.

Jens

All of the electronic governors that we have used in the past are solenoids with position feedback and drive against a fairly heavy spring. The PWM drive keeps the current down and engine speed sensing feedback gives the drive something to work on.

The Barber-Colman actuators were straight linear solenoids with ball bearing sleeves to cut friction, the Ambac ones were a swinging arm and solenoid, others may have been different.

Controls were speed, droop, sensitivity.

Electronics were pretty simple, very small box on the side of the solenoid with a couple of small PCB's and one power transistor to drive the solenoid.

Peter

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Re: An Affordable Electric Genset Governor?
« Reply #6 on: October 09, 2007, 02:16:53 PM »
Mike, count me in for one of these. Still interested in a gib key puller as well.

carlb23

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Re: An Affordable Electric Genset Governor?
« Reply #7 on: October 09, 2007, 03:04:58 PM »
I am very interested and if all works out well count me in as well

Carl

JohnF13

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Re: An Affordable Electric Genset Governor?
« Reply #8 on: October 09, 2007, 06:29:53 PM »
What is th time line for getting these things in production?  I'd be interested in at least 3 if it's not too far down the pipe.....
John F
2 x 6/1 JKSON.  1 x 10/1 JKSON, 1 x 27hp Changfa, 1 x 28hp AG295, 1 genuine 1939 SOM, a couple of others in test mode and a Hercules Multu-fuel still in the box.

listeroidsusa1

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Re: An Affordable Electric Genset Governor?
« Reply #9 on: October 10, 2007, 03:49:37 AM »
My Darlington transistors that will drive the solenoid arrived today but it will be this weekend before I have a chance to install the control on one of my engines. I've been teaching at our local community college and I have a class tomorrow evening so that knocks out having time to hook up the system. I'm anxious to test one of these but it'll have to wait until I have some free time this weekend. I started out designing a digital system but along the way it has evolved into an analog system. It is simpler, more people can understand it, all parts are readily available, and even in kit form its simple and easy to build. A transistor to enable the chip will provide protection against signal loss from the tach/generator. The tach/generator will supply base current to the transistor which will supply power to the chip. There will be no power supplied to the chip unless there is a signal from the tach/generator. If the electronics aren't working the engine will simply use the existing governor. It will be simpler to hook up and run than it is to explain how it works.

MeanListerGreen

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Re: An Affordable Electric Genset Governor?
« Reply #10 on: October 10, 2007, 11:16:02 AM »
If your test runs are sucessfull I will take one.  So. put me on your list.  Thanks.
MLG Gib Key Pullers

rcavictim

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Re: An Affordable Electric Genset Governor?
« Reply #11 on: October 10, 2007, 11:42:42 AM »
Peter,

Are you proposing to incluide the required solenoid in the kit?  If not, where might one find a suitable solenoid?  Here in Canada, Princess Auto stores carry a wide assortment of small DC PM motors that would likely be good candidates to act as the tachometer generator.

What voltage DC motor does one need here?  Does your circuit use a potentiometer as an adjustable divider to set different motor voltages at whatever the user drives the motor with mechanically resulting in goodness knows what speed, to what the circuit requires?
-DIY 1.5L NA VW diesel genset - 9 kW 3-phase. Co-gen, dual  fuel
- 1966, Petter PJ-1, 5 kW air cooled diesel standby lighting plant
-DIY JD175A, minimum fuel research genset.
-Changfa 1115
-6 HP Launtop air cooled diesel
-Want Lister 6/1
-Large DIY VAWT nearing completion

Andre Blanchard

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Re: An Affordable Electric Genset Governor?
« Reply #12 on: October 10, 2007, 04:47:06 PM »
Here is an idea for a simple governor.
I use the same circuit for a speed control on an electric feed for my milling machine, works great.
Here it would be working in torque mode.  The tread mill motors have decent ball bearings and enough mass they should handle the heat without the cooling air from spining.

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listerdiesel

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Re: An Affordable Electric Genset Governor?
« Reply #13 on: October 10, 2007, 05:31:50 PM »
Peter,

Are you proposing to incluide the required solenoid in the kit?  If not, where might one find a suitable solenoid?  Here in Canada, Princess Auto stores carry a wide assortment of small DC PM motors that would likely be good candidates to act as the tachometer generator.

What voltage DC motor does one need here?  Does your circuit use a potentiometer as an adjustable divider to set different motor voltages at whatever the user drives the motor with mechanically resulting in goodness knows what speed, to what the circuit requires?

We always used a mag pickup on either the starter ring teeth or if no teeth then a large timing gear would do the job.

Mag pickups were two-wire, coil around a magnet type and pretty simple. Drill and tap 5/8" UNF and screw and lock into position (allowing clearance obviously) Occasionally a piece of swarf would get stuck on the pickup tip, which was the magnet pole, but we never lost the governor through that.

Most had speed detection loss shutdown.

Peter

rcavictim

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Re: An Affordable Electric Genset Governor?
« Reply #14 on: October 10, 2007, 06:03:06 PM »
Peter,

Are you proposing to incluide the required solenoid in the kit?  If not, where might one find a suitable solenoid?  Here in Canada, Princess Auto stores carry a wide assortment of small DC PM motors that would likely be good candidates to act as the tachometer generator.

What voltage DC motor does one need here?  Does your circuit use a potentiometer as an adjustable divider to set different motor voltages at whatever the user drives the motor with mechanically resulting in goodness knows what speed, to what the circuit requires?

We always used a mag pickup on either the starter ring teeth or if no teeth then a large timing gear would do the job.

Mag pickups were two-wire, coil around a magnet type and pretty simple. Drill and tap 5/8" UNF and screw and lock into position (allowing clearance obviously) Occasionally a piece of swarf would get stuck on the pickup tip, which was the magnet pole, but we never lost the governor through that.

Most had speed detection loss shutdown.

Peter


Peter,

Sorry, I misdirected the previous questions in error to you.  They were meant for the fellow making this kit, Listeroidusa1.
-DIY 1.5L NA VW diesel genset - 9 kW 3-phase. Co-gen, dual  fuel
- 1966, Petter PJ-1, 5 kW air cooled diesel standby lighting plant
-DIY JD175A, minimum fuel research genset.
-Changfa 1115
-6 HP Launtop air cooled diesel
-Want Lister 6/1
-Large DIY VAWT nearing completion