discogodfather
New Member
I recently got a small permanent magnet alternator online. It's only advertised specs are a series of power ratings at speeds, this one is supposed to produce 100w at 3000rpms, around 20-30v. It's single phase and has two wires.
My project goal was to take this PMA and drive it at 3000rpm's and try and see if I could get useable 120vac from it. I started by grabbing a full wave bridge rectifier (rated for 30 amps) and got the setup to produce 20-30v DC. Then I took a DC to DC converter (uses a Buck Boost curcuit) to take the 20-30v and convert it to a solid 12v.
From there the system is connected to a 100w pure sine inverter. Everything starts up fine and my meter reads 120vac. I am looking for my scope to verify the wave, but the inverter is a good quality samlex.
Now comes the PROBLEM! When I attach a load the whole system shuts on and off rapidly. Voltage drops hard from the PMA (around 10-15v) and the dc to dc converter looses its 12v, sometimes dropping below 10v. The inverter beeps and turns on and off. I have been careful to only apply resistive loads (no capacitive and inductive) mostly 15, 40, and 60 watt incandescant bulbs. They seem to light up to nearly full brightness but only stay on for a moment, then on and off rapidly. There is an RPM drop under load but I end up compensating for that and it dosen't solve the problem.
I can't seem to find anything on similar projects on the web and fear my ignorance is getting the better of me- is it possible to get decent AC power directly from a PMA? Most people seem to be using them for DC battery charging.
Some of my system specs:
PMA - single phase 2 wire, 100watts at 3000rpm
Bridge Rectifier (30 amp, full wave)
DC to DC converter, takes 0-30v (input is 20-30v) and produces a solid 12v
12v Samlex Pure Sine 100w inverter
My project goal was to take this PMA and drive it at 3000rpm's and try and see if I could get useable 120vac from it. I started by grabbing a full wave bridge rectifier (rated for 30 amps) and got the setup to produce 20-30v DC. Then I took a DC to DC converter (uses a Buck Boost curcuit) to take the 20-30v and convert it to a solid 12v.
From there the system is connected to a 100w pure sine inverter. Everything starts up fine and my meter reads 120vac. I am looking for my scope to verify the wave, but the inverter is a good quality samlex.
Now comes the PROBLEM! When I attach a load the whole system shuts on and off rapidly. Voltage drops hard from the PMA (around 10-15v) and the dc to dc converter looses its 12v, sometimes dropping below 10v. The inverter beeps and turns on and off. I have been careful to only apply resistive loads (no capacitive and inductive) mostly 15, 40, and 60 watt incandescant bulbs. They seem to light up to nearly full brightness but only stay on for a moment, then on and off rapidly. There is an RPM drop under load but I end up compensating for that and it dosen't solve the problem.
I can't seem to find anything on similar projects on the web and fear my ignorance is getting the better of me- is it possible to get decent AC power directly from a PMA? Most people seem to be using them for DC battery charging.
Some of my system specs:
PMA - single phase 2 wire, 100watts at 3000rpm
Bridge Rectifier (30 amp, full wave)
DC to DC converter, takes 0-30v (input is 20-30v) and produces a solid 12v
12v Samlex Pure Sine 100w inverter