I want to use some metal halide lamps (5-7*150W) to get some decent lighting in my room.
Unfortunately, inductors for these lamps have weight about 2kg each. I cannot accept 10kg of metal hanging near the ceiling :-) So I must go with electronic ballast, but their cost is about 100 bucks per lamp. Forking out 500 bucks does not sounds good.
So, I am thinking about making 5-channel electronic ballast for these lamps. While basic idea looks simple (just make constant current supply), the main problem is ignition.
Is it possible to avoid HV ignition by feeding RF signal into lamp, so that discharge would start just like in induction lamps, and after some time turn on the current?
And finally, do I still need alternating current direction in the lamp? If yes, how fast it should change?