Crazy, Ignorant, Electrical generation question....

[Dualfuel]

Say I have two small generators...AC putting out 115 volts...can they be synched up some how? So they could run on the same circuit?

Or say I have one small synchronous generator and a engine turning a motor as a generator...I think I can see how to synch up that arrangement.. Is there already a thread here, about that, full of X-members who are now dead because of stupid experiments?

Geez, I mean how do the big boys bring extra generators online?
Is this slighty interesting or is this just going to be treated with the evil question...Why? Hell I don't know why, but it seems interesting, so I thought I would ask.
BPJ

[Ronmar]

The term you are looking for is "Parallel"... Yes, they can be synced, but you need to build a simple light circuit to get them into phase before connecting them together.  Trying to sync generators out of phase tends to let the magic smoke out.  When synced in phase, they are basically locked together by their rotating magnetic fields.  There can be issues however as the voltage regulators may fight each other, as may the engine governors.  Large multi generator power systems have interconnect circuitry that helps the governors and regulators to work together, and to automatically pull a generator off the line if it is unable to carry the load.  Motoring a generator when it's engine fails is generally considered to be a bad thing, again with the loss of magic smoke:)

Putting a syncronus motor into service as a generator is considerably easier.  The syncronus motor will automatically sync to the AC if started on the AC, then connected to the engine.  Easiest way to do this is to use the motor  to start the engine.  After that it is a matter of adding torque beyond that required to spin the motor at it's rated AC RPM.  Easiest way to describe this is to imagine a boat motoring along with an ocean swell.  Lower the engines output and the swell catches the boat and it starts to push the boat along(AC current flowing into the motor providing the power).  Add engine throttle and the boat accelerates to ride down in the trough, engine and wave provide the rotational force equally, so no current is flowing either way.  Now add throttle and the boat starts to accelerate up the back side of the swell, pushing the swell along(current gets output from the motor and backfeeds to the outside line. 

Google "parallel generators"  and you will find plenty of info to satisfy your curiosity.

[Dualfuel]

More CIEQ's....Ok say I have a battery  bank at 12.4vdc...I start chaging them with panels whose open circuit output is 14amps @19 vdc....what is the wattage? Is it 19-12.4? for the voltage? It seems the wattage is wasted until the panel voltage exceeds the battery voltage...pls explain this in laymen's terms...hell, do it with equations, I don't care, its just confusing. I got to thinking about how to provide some actual numbers for the Yanmar and Kubota fuel consumption...and fell short.

[BruceM]

When your solar panels are hooked up to the battery, they will provide watts equal to whatever the battery voltage is at any point multiplied by the measured current flowing into the battery at that same time.  The maximum power rating for the panel is only a measure of the panels capability compared to other panels you might select and you will not see that wattage in actual use, as you won't be running your battery voltage that high.  You could measure your panel's output for a range of voltages and create a "power curve".  They will put out more watts total at higher voltage and somewhat less amps.

This is what the maximum power point tracking (MPPT) solar chargers take advantage of, by letting the panel operate at it's maximum power voltage, while stepping down that voltage in an efficient manner (increasing the current at the battery voltage).  The increased capacity is not really that significant in most real world applications, but some people think otherwise. I don't like the EMI generated from any of the pulsing charge controllers and like the simple on/off temperature compensated ASC charge controllers for 12/24V instead.

The better manufacturers like Kyocera underate their panels and on a clear sunny summer day their newer panels beating their max wattage specifications.  A 100 watt bargain Chinese panel will actually put out about 80 watts brand new and that will fall over time.