high voltage triac circuit

[yougarage]

I want to build a simple "switch" to interrupt the supply to a moped ignition coil (Capacitive discharge ignition), it is fed with AC voltage, varying from 200 to about 500 volt depending on the RPM of the engine.
I need to drive this switch with a microcontroller, so i thought to use a triac and an optocoupler, but due to this wide voltage range, how do I select the gate resistor?
If I choose a low OHM value, the gate will melt at higher RPM, and a high value will not provide enough current to the gate during the engine start.

 

[tpetar]

My friend did you check speed of triac ? there is lots of CDI on Internet.


Electronic Motocycle ignition CDI Honda C-90
This Circuit is for 4 cylinder motor, Electronic Motocycle ignition for CDI Honda C-90.
Use small circuit but good work. SCR 1 TIC106 Switching Component for drive ignition Coil to Sparkplug. Detail to see circuit.


There is lots and better circuit on Internet but this is simple one, make search...

 

[yougarage]

Thanks for posting this picture, but I don't want to make an electronic ignition, I just want to interrupt a working one, let's say i need to interpose the switch between the generator and the ignition coil
I modified the previous picture so I can show you.

 

[tpetar]

My advice its to use some optocoupler there and fixed stabilized voltage for gate, there are lots of examples on Internet for that.