Talk:Gate turn-off thyristor

Dubious
The following is found in the article: "It may however be noted that the turn off time of a compareable SCR is ten times that of a GTO. Thus switching frequency of GTO is much better than SCR." What?? This is completely opposite of the data given, as an SCR takes 15 microseconds to turn off and a GTO takes 150 microseconds. --Notfed 17:49, 22 April 2007 (UTC)

If you look at the same page in Italian you can see an identical table which differs for the last line, in fact that one seems to respect what is said before: GTO 15 microseconds and SCR 150 microsenconds. Could this one be the right one? --Laurentio86 (talk) 15:22, 21 April 2011 (UTC)


 * The test conditions are completely different. A SCR turned off by an external circuit and a GTO turns itself off.  In an apples to apples comparison, the GTO is much faster Wefoij 22:15, 2 September 2007 (UTC)


 * I'm sure you're correct, but the quoted claim is still non sequitur with regards to the table's data, which is why I brought it up. In my opinion, the speed comparison is an important distinction between semiconductor families and hopefully someone can find a way to phrase it a little more clearly.--Notfed (talk) 23:28, 2 February 2008 (UTC)

Sections
I'm adding sections to the article to make it easier to follow Wefoij 22:17, 2 September 2007 (UTC) I have some reservations about the statement that GTO devices are made up of hundreds or thousands of smaller dies. This is not my personal experience. The large devices (2400Volts 1500 amps) I've encountered have a single die with a ring gate. See Data sheet ABB5SGA30j2501.pdf. IGBT devices, that I have used in similar power ratings, on the other hand are made up of multiple dies bonded to a common heatsink and connected via silver wires to the external terminals. IGBT devices of course have all but displaced GTOs from the market place and it is probably only people like myself who work with legacy equipment that will encounter then in the future. See Hitachi MBN1200E25C.pdf Large traction inverters employing these devices have a spped limit on their switching at about 700hz and the shortfall is compensated for by changing the mode of control as speed of the motor increases. The drive will start with PWM at standstill and then switch to modified sinewave once the rotor is regenerating and finally square wave at higher speeds. The later models incorporating IGBT devices stick with the same methodology (both GE and Siemens with ABB to be confirmed). — Preceding unsigned comment added by Modelmakeroz (talk • contribs) 04:34, 13 January 2012 (UTC)