Datasheet MCC, MCD, MDC (IXYS) - 5

IXYS Thyristor/Diode Module Types M##501-12io2 to M##501-18io2 8.3 D.C. Thermal Impedance Calculation
−t
⎛
τ
rt = ∑ rp ⋅ ⎜1 − e p
⎜
p =1
⎝
p=n ⎞
⎟
⎟
⎠ Where p = 1 to n and:
n
t
rt
rp
τp = number of terms in the series
= Duration of heating pulse in seconds
= Thermal resistance at time t
= Amplitude of pth term
= Time Constant of rth term The coefficients for this device are shown in the table below:
D.C.
Term rp τp 1 2 1.37×10
7.6×10 -3 4.86×10 -4 8.6×10 -3 -3 3 4 5 0.0114 0.0223 0.0221 0.101 0.56 3.12 9.0 Reverse recovery ratings
(i) Qra is based on 50% IRM chord as shown in Fig. 1 Fig. 1
150 µs (ii) Qrr is based on a 150 µs integration time i.e. Qrr = ∫i rr .dt 0 (iii) K Factor = t1
t2 Rating Report. Types M##501-12io2 and M##501-18io2 Issue 2 Page 5 of 10 August, 2011