Transistor is destroyed by circuit

Super I a forum power controls  that a HV has Department have...
Because I would have because a problem with a simple circuit to control a zeilentrafo...
I use this engineer construction: on my ignition coil I have during the primary to collector and + 15 coils, leads and the control coil between the 2 resistors and the base 4 coils
My working voltage is 30V (set to 2A, in use it fall to 14V)
This circuit has all my 2n3055 (3 pieces were there), and one of my new Tesla has fried KD501...Therefore I am now looking for a way to filter these spikes out.What there does anyone know?

So FYI, these KD501 things are comparable with the 2n3055 and costs just 3 euro spontaneously in the 10erpack'd I hang a freewheeling on the transistor between GND and emitter? Has not dealt with the "echo" of various circuits still anti-parallel to the emitter collector circuit, he says. So that the normally conducts no electricity. It keeps away negative voltage peaks of the transistor. I would install no transistors from the 60s for something first, except it should be classic. Secondly, the circuit for 12V is not dimensioned, for 14, and it didn't for 30V. A diode from the collector to the emitter (between GND and emitter would be shorted:D) not much would bring great positive voltage spikes are the main problem. A 2N3055 withstands 60V only and if you're already an operating voltage of 30V, it's not much. This circuitry actually thrives on the induced voltages, so it would make sense to do a transistor with higher dielectric strength. Between collector and emitter of the transistor, a suppression diodes n would be appropriate (especially when a 2N3055, if you really want to use). I use the KD501 engineer, they are comparable with 2n3055
and have these values:
NPN
40V
20A
150W
At 12V not much comes out of the ZT, as the power supply unit creates only 2A... so I'll have the primary coil longer (more coils) make, so I can only relate more power at 24V is a 2cm ignition, at 30V, a 3-3.5cm actually thrives this circuit the induced voltages, so it would make sense to do a transistor with higher dielectric strength. Between collector and emitter of the transistor, a suppression diodes n would be appropriate (especially when a 2N3055, if you really want to use).

There doesn't make sense it would be a resistor to make between the drive coil and base? If no 2n3055, which then? the 2n3055 and the KD501 are made acceptable by the price. And when the Suppression diodes n, it does not matter which I guess? These should be designed for the Spannungsbereicht?