Well just basic testing here, but it seemed to work ok. Used more feul than power created so of course not doing it much yet.
Simply put, I connected an AC motor to run off the grid as normal, this syncs the motor to the grid. Start engine, this runs the AC motor faster than rated speed and it produces power instead of using power, this feeds the house or grid. AC motor can be used as starter for the gennie engine
If power goes off the motor will still be spinning on the engine but not producing any power, not sure what happens when the grid comes back on. My "GEUSS" is the grid and AC motor will sync back togther again since the motor is not then producing any power. That is a geuss because the grid did not go down durring testing and I did not think to try it by flipping off the main power then back on again
HOWEVER, I would not be wanting to run the engine for nothing when the grid is down this way, SO I think since there is only power when the grid is live, it should be very easy to put a switch in the line to shut off the engine when the grid is down!!
Now what you have is an AC motor that runs off the grid as a starter for your Diesel engine and a controll switch to only have the engine running when there is grid power. So the AC motor starts the diesel engine which runs the motor faster than it's rated speed and produces power only while the grid is live. When the grid dies the AC motor also stops making power, the switch then shuts off the diesel engine. When the grid power comes back on the AC motor is still connected and starts the diesel again.
Some what automated system, and when you don't want it running just flip off the breaker for it so the grid power is off.
Just don't forget and end up working on the system turned on durring a grid power failure where it could start unexpectedly.
If you just set it up to run all the time with out a switch to shut off the engine durring a grid outage and wonder what happens when it comes back on again.
SHould be easy enough to test, shut off the breaker to the motor, have load between breaker and motor. Load should go dead after you shut off the breaker, not stay on. Then turn breaker back on and watch for smoke or boom, if load comes on and everything runs fine then the motor should have re-synced to the grid and is a gennie again.
I would do this when I could shut off everything except the gennie system being tested!
This way the metter should not be running at all. Meter shows power being used when you run the motor on AC power, also a load like a light bulb. Start engine and when AC motor over speeds the light should be working fine, and you should see the metter spin backwards if your making more than 100watts power the light bulb uses
When you flip off the breaker to the gennie taking it off the grid, the light bulb should go off if the AC motor is no longer producing power (it should not be, and the bulb should be out.)
Then the big test, flip the breaker back on :O
The bulb should light and the meter spin backwards again if all goes well.
Some meters will not spin backwards though even though you are feeding power to the grid, so check that first. If you are running the gennie and a load but the meter is not trurning at all then yours may not go backwards. If so I would add larger loads like 500watt bulbs and see if the meter spins forwards, if not then your gennie is making power and your not using grid power for the load, but the meter is not running backwards.
Basically it take the grid to energize the motor so that it can generate power, no grid no power. This is not using any caps!! Using caps is if you want it to generate power without being connected to the grid, the caps energize the motor kinda like the grid would, except you will always be making power.
For grid tied gennie you do NOT want to feed any power to the grid if it goes down, that could hurt or kill workers not expecting it, so I would NOT use caps on the AC motor. If you need power when the grid is down, do somethng else for that power but DON'T be feeding the grid while doing it.
Properly built and installed, no-one should ever even know it's there unless you tell them or the meter reads less later than it did before
That's what I will be doing when all my stuff is completed someday (if ever), just holding the meter near zero best I can till I can get off grid completly.
If the grid is up I can feed it, when down I can't, and in between no-one knows.
Primarily the house will use most of the power that's made anyway, but for things like 220 well pump I'll need the grid for while, so the well eats 220 from the grid, and the gennie gives it back.