AW: Re: [EVGRAY] Re: buck plug ...

Body

Hi Mick, with the diode plug, the energy from the discharge capacitor comes to switch and discharge. No extra energy is required for the control as it is classic. There will be losses here as well. I have the feeling that the losses are to be found in the diodes and thyristors in the internal resistance. And there can not compete Mosfet or igbt. Greetings Sven

Von Samsung Mobile gesendet

-------- Ursprüngliche Nachricht --------
Von: "Mick [email protected] [EVGRAY]" <[email protected]> 
Datum:07.01.2018  15:01  (GMT+01:00) 
An: [email protected] 
Betreff: Re: [EVGRAY] Re: buck plug ... 

Sven,

The new graphite foam heat sinks are becoming available maybe next aerogel.  They should just make the part encased in aerogel with the leads sticking out.
I have had my eyes on the SiC FET The diodes sound very interesting too, obviously the SiC junction can handle much more heat. Have FUn!
Yes we are finding many reasons Hector likes SCR's  not static sensitive, automatic cutoff at low current node, unidirectional, can take abuse.  Obviously one difficult part of the design is as a low impedance controlled device they need enough current to switch fast enough therefore FET  or fast small transistor driver like gallium arsenide opto gate driver8-)

On 1/7/2018 6:54 AM, [email protected] [EVGRAY] wrote:
 
Hi Ole, on the link you wrote me came this answer. I have SiC diodes to test. I screwed it extra on a large heat sink. so that I notice when they should heat up a lot and that the heat can be dissipated well.

I think Hector did not use 180A diodes for nothing. The flow of electricity must be extremely high, even if it is only for a peak, I think.

I would like to measure with the Scope soon on diode D2 and D5 of the Buckplug circuit.

regards

Sven


https://electronics.stackexchange.com/questions/6151/is-paralleling-diodes-a-bad-idea


"Silicon Carbide (SiC) diodes can be paralleled without problem.

As one diode heat up its resistance increases so other diodes taking up more current. Current equalizing is guaranted by SIC semiconductor material. You don't have to worry about thermal runaway. However they are still expensive."