Hitachi IGBT Module Application Manual
5.7
Dead Time
5.7.1 Dead Time Logic in IGBT modules
5.7.1.1
Typical Configuration
Consider an example involving a voltage inverter. Figure 41 shows a single-phase configuration for the
top and bottom arms which represents a typical configuration of a major circuit (one phase worth). Top and
bottom arms are provided between the P and N of a DC voltage E
o
, based on the assumption of a mode
where the IGBTs of the top and the bottom arms alternately keep turning ON and OFF. To prevent power
supply short-circuiting due to simultaneous ignition (commutation), a top and a bottom IGBT OFF period
(dead time) are set using a control signal. This dead time period is also known as the non-lapped period.
Figure 41. Typical Configuration of a Major Circuit
5.7.1.2
Comparing Dead Time and Real Dead Time
IGBT collector-emitter voltage.
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