"Governor" Constant RPM Control for Generator Application

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UglyBoost91
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Posts: 8
Joined: Tue May 06, 2014 12:42 pm

"Governor" Constant RPM Control for Generator Application

Post by UglyBoost91 »

Hello all,

Long story short, I have a home brew Generator using a 1984 Dodge 2.2L NA 4cyl connected to a surplus 30kw generator head. It was carburated and used a complicated mechanical goevernor system to keep the engine at 1800 RPM for 60HZ electricity, but it is unreliable and I have an unused megasquirt setup I had built and ran on a Dodge Omni. I also want to be able to really optimize the spark and fuel tables to add fuel efficiency since I will be running at a constant speed. So the gears started turning...

Does anyone have any insight into setting up the megasquirt for a constant speed situation?

My thoughts were to use the PWM idle output to control a large stepper motor on the throttle body.

I'm not mechanicaly challenged and have built a few megasquirts for "normal" and race cars, but computer code makes me feel like an idiot, so I'm trying to teach myself.

Any reason this could not be accomplished using the PWM output and idle control inputs in Tuner Studio without software modification? I already have a large 4 pole stepper from some industrial equipment that I could machine an adaptor and bracket for...

Thanks! Yes I know a dodge 4cyl to a generator is dumb, but I already have the hard part for free, so some modern controls would be nice!
grom_e30
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Joined: Thu Mar 08, 2012 12:44 pm
Location: UK

Re: "Governor" Constant RPM Control for Generator Applicatio

Post by grom_e30 »

why not use the closed loop idle and set you target idle speed to 1800 rpm
1990 bmw 320i daily driver with m20b25 ms3 sequential fuel, 380cc injectors, d585 coil near plug, home made cam sync, launch control, fan control, vss, homebrew egt logging what's next????
elaw
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Location: Wilmington, MA

Re: "Governor" Constant RPM Control for Generator Applicatio

Post by elaw »

Wow this sounds eerily familiar... I've got a 20kW generator with a Ford LSG-423 engine which is basically a Pinto motor if you're old/unfortunate enough to know what one of those is. :lol: It's carbureted with propane now but I'm planning to Megasquirt it in stages. First will be timing control, hopefully to gain efficiency as you indicate. Next will probably be RPM control which I'll first try with CL idle. In my case I need 3600 RPM and I'm not sure CL idle can even go that high, but we'll see! Fuel control will come later.

Anyhow that's all in the future so I can't offer much right now except moral support. Except one thing which you may or may not know already: you can't use a PWM output to control a stepper motor! You either have to use the stepper idle outputs with a stepper motor (and watch the size because the power from those outputs is limited) or use a PWM output with some other type of motor. I've actually considered (but not tried yet) using an R/C plane or car servo to control the throttle on mine... such servos can be run off a PWM output with some creativity.

Keep in mind that unless there's a spring on it, moving a throttle plate should not take all that much force. So you may not need as large a motor/actuator as you think.
Eric Law
1990 Audi 80 quattro with AAN turbo engine: happily running on MS3+MS3X
2012 Audi A4 quattro, desperately in need of tweaking

Be alert! America needs more lerts.
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