What we had to do for the petrol engine

Well what would you do if you give a small mounted engine with an alternator that has a 3 phase output, well you get the engine running by a proven method of trial and error and it also helps if you have a bunnings expert who sells lawn mowers and bam you should end up with a spluttering engine.

Next we see what kind of power we can get out of our little red engine a dummy load is the requirement hooked up in a star connection we chuck on the leads for our multi meter and we got what could be compared to left over scraps in other words hardly any voltage.

After a bit of head scratching we worked out the alternator needed an exciter to get the output we dreamed of. So that means putting a 12V battery in to the alternator and now the dummy loads are getting 19V each.

We were finally getting an alight output out of the engine but all agreed it could be better so came up with a plan. Get someone better than us at using motors to make the good better and so Marty and Nick set of to the automotive workshop and grabbed a tutor. After he cleaned the oil filter and replaced the expired petrol we now had 26V output on each phase.

Feeling pretty good about how things were going we decided to make for the summit and tackle the next problem changing the 3phase AC output into a single phase DC output so we could feed a DC busbar now change can be easy especially with six diodes hocked up strategically we managed to get that sweet DC output.

With the finish line in sight and unexpected issue came up the output was to high a decent 60V. Now we can usually agree bigger is better but not in this case as the busbar requires 24V the solution a variable resister hooked up in series along side the exciter (the battery) to change how much current the exciter gives to the alternator which affects the output of our circuit.

The end product we ended up with is a variable single phase DC generator.