[Skipperdan]

Hello all, I have looked through the posts that have been posted, but I thought it would best to start my own rather than hijack another.

I am working on a boat but it should be similar to a car. I have a 60v 3 kw AC induction motor powered by 5 lead acid batteries. I started out with a Honda 2000 and a 60v 10 amp charger. This works to charge the batteries, but it only gives me 10 amps to run the motor. I need closer to 60 amps. I also just put together a 5.5 engine and a big truck alternator with a dummy regulator so I can run it up t o 75v. I have not tried it out yet but it should work. While researching the project I came across many other options. So now I am asking the experts what do you think is the best way to accomplish my system.

The Honda 2000 is a nice package small and quiet. Generates AC converted to DC then inverted to AC. any way I can utilize the DC before it gets inverted?

How hard is it to just build a 75v charger from 110v. Not automatic, but manual so I can adjust the Volts and amps. I want to run the motor as I charge the batteries, but then also just charge the batteries at a lower amp setting at times. I do have solar to top everything off and keep them balanced. One solar panel and controller to each battery.

Thanks in advance, Dan

 

[brian_]

The Honda 2000 is a nice package small and quiet. Generates AC converted to DC then inverted to AC. any way I can utilize the DC before it gets inverted?

It seems likely that the input to the inverter could be tapped, but then you would need to run a DC-to-DC converter to get to the required charging voltage, and you would have the issue of how the generator set is controlled.

If you were to build the converter, it would probably make more sense to tap the power before the rectifier, so your converter would be a high-frequency AC-powered charger... but you would still need to understand and deal with the control of the engine.

 

[brian_]

The wiring diagram from the owner's manual for a Honda EU2000i is shown below. A single component (called the Inverter Unit) contains the rectifier, inverter, and engine control logic - note the output to a throttle control motor.

That means that you can intercept the raw 3-phase AC power from the windings, but not DC before the inverter (ignore the "DC winding" and rectifier shown - they are only good for a few amps of poorly regulated 12 V). It also means that if you draw power there (from the main windings), the engine speed will not likely be managed by the inverter unit to provide enough power. You might get away with turning the Eco-Throttle off - hoping that the system would apply the throttle needed to maintain constant engine speed - but that's not a quiet or efficient way to run a generator set of this type.