[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Terry's sisg paper
Original poster: Redmo@xxxxxxx
I am reading your sisg.pdf paper. Great work! I have two questions.
1) If the primary freq is 250 khz and peak current is 500 A. you
state that the rate
of current increase is 500 A/us. If the primary current is modeled as
a sin wave
near time = zero, we have:
I = Ipeak * sin(w*t)
dI/dt = w*Ipeak*cos(w*t)
dI/dt = w*lpeak near t = 0 so
dI/dt = (2*pi*250.*10^3)*500 = 785 A/us
2) The 192 ns you calculate to charge the IGBT gate cap to 9 volts
assumes 25 volts on C1. but it took 100 ns to charge C1 to 25 volts.
So don't you have to add 100 ns to the 192 ns to get 292 ns of time
before the IGBT turns on?