[TCML] Re: IGBT CM600 max current ?

[Finn Hammer]

Gary Peterson skrev:
> Greg wrote:
>   
>> . . . In my opinion, it does not make sence to speak about BPS with a [CW
>>     
> oscillator type] coil like this, unless you pulse it.
>
> Yes, it is a CW (continuous wave) oscillator.  I am pulsing the 137 kHz
> transformer at a rate equivalent its resonant frequency and with a 49% duty
> cycle.  Rapid rise time and cut off by the circuit controller or break, that
> is to say, the solid-state switch, is critical to achieving proper
> performance.  I call this switching rate the "break rate" with the unit
> being "breaks per second" or "BPS."
>
> I have been planning a 75 kHz Tesla coil with an improved power amplifier,
> incorporating a single CM600, for my next project.  It occurs to me now that
> the CM600 would not be able to keep up at that frequency, allowing fully
> 'undamped' CW operation.  
>   
I don`t have any nexperience with this kind of system, so can`t comment 
on the suitability of a CM600 here.
>   
>> . . . you could only achieve up to 2500 BPS, because the [50kHz] coil
>>     
> rings around 5-10 cycles at Fres . . . so all in all, there is not time
> available to get any higher.
>
> In other words, the fastest rate at which I will be able to get the CM600 to
> switch on and then off is 2,500 times per second with an 'on-and-then-off'
> interval of 10 microseconds (.00001 sec.), do I have that sort of right?
> I'm a little confused by your explanation.
>
>   
My comments apply to a disruptive tesla coil.
I trust you are familiar with the operation of this, the mother of all 
tesla coils.
Ringdown, say 10cycles @ 50kHz would occupy 200µS at every break.
Let`s be generous and say that we can recharge the cap in the same time.
That gives us 400µS/break, or 2500BPS
Hope this is clear

>> Unfortunately, the broken links are so forever.
>>     
>
> Do you still have the original images?
>   

Several crashed harddisks down the line, I`m afraid.


Cheers, Finn hammer
> G.P.
>