Hybrid powerplant for a pumpjet propulsion engine

I find these posts here on the Arduino forum quite amusing.

I'm putting together an engine for a hybrid electric/gasoline waterjet engine. The Arduino is controlling the RPM of the gasoline engine connected to a generator to feed the best electrical power out depending on the demand based on the throttle grip.

This is not easy as the gasoline engine has it's top performance and horsepower at 6000 rpm but that is not always required but to charge batteries.

Connected to the gasoline engine is a 1Kw generator that delivers the electrical power to the pumps for propulsion. So my setup aims to keep the gasoline engine to deliverer it's best at all times independent of what acceleration required.

So you you twist the handle and the Arduino figures out what engine rpm's are required to perform the action.

The waterjet pumps are not huge, just above 6litres/sec at maximum, but electric. And the power comes from the gasoline powered generator.

So I figured, get the measured required power from the handle, turn up the rpm of the gasoline engine by means of an rc-servo to make the generator deliver the required power and feed that to the pumps?

It has to decide when to feed the pumps directly and when to charge batteries.

Easy huh?

The grip is just an input of what I want to do, fly-by-wire.

The Arduino decides what to do.

For a generator I took the universal motor from a vaccum, that is 2kw at 20k rpm. Running it as a generator, with some rewiring, it delivers 1KW at 8K rpm.

Or 90 volts at 11 amps.

Those universal motors make great high rpm generators :)

I entered it to the Hackaday Prize Contest.

Doesn't sound like enough for a Jetlev.

Paul__B: Doesn't sound like enough for a Jetlev.


To lift you straight up that thing needs alot of thrust. More than your weight plus the weight of the backpack.