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Hello, Is it possible to know the value of the tun on conction losses of the IGBT NGTB40N60IHLW-D. I only see the turn off switching losses in the datasheet. Thanks, Lucie SCHMITT

IGBT conduction losses are a function of the following:
1) Collector-emitter saturation voltage Vce(sat) also known as Vce(on).
2) The current flowing through the IGBT at the time of loss computation.
3) The junction temperature of the IGBT.

The current flowing through the IGBT is determined by the load, and operating point of the application. To compute conduction losses, you will need the Vce(sat) value. (obtainable from the IGBT data sheet).

How to obtain this value? Look at the curve from the data sheet of the IGBT NGTB40N60IHLW (page 3) figure 5. The figure shows the relationship between all the parameters listed above 1), 2), and 3).

First, obtain/determine the values of Ic and Tj (operating point) from the application. Then using these values, the corresponding Vce(sat) curve can be obtained. The conduction losses is computed as a product of Ic and Vce(sat), integrated over the period during which the IGBT is conducting. If you define a specific operating point [Ic, Tj] in the application, the corresponding Vce(sat) value can be obtained by extrapolation.

The curve on figures 1 and 2 provide information on how Vce varies with the collector current for different gate drive voltages. These curves can be used to determine the collector-emitter resistance at a particular junction temperature and gate drive voltage. This value then can be used to compute the conduction loses at a given value of Tj.

Please see our IGBT NGTB40N60IHLW datasheet.
Answered by:
ON Semiconductor
2013-04-30 14:16:10.821