Issue of dead time in Active short circuit test with TOP / BOTTOM IGBT's

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User19994
Level 1
Level 1
Hello,
we are using Tricore TC1782 controller in our motor control drive & driver is designed & controlled using GPTA timers(LTC's).
As per application requirement, we are doing extra DC voltage compensation due to back emf if speed is high.

It is done by ACTIVE SHORT CIRCUIT algorithm where with time sequence TOP IGBT's or BOTTON IGBT's are turned ON completely.
However, doing this we see either TOP or BOTTOM IGBT's are ON but there in no DEADBAND time in between leg. So both upper & lower are HIGH or LOW at the same time & causing switching issues
at field.

The method used to ON -OFF IGBT's,
1. TOP all ON - for example
LTCx timer register lower = full PWM period
LTCx timer register upper = full PWM period

2. BOTTOM all ON
LTCx timer register lower = -1;
LTCx timer register upper = -1;

Please help us here, how to create a dead band while doing the above operation.

Thank you!

regards,
Girish Mane.
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1 Reply
NeMa_4793301
Level 6
Level 6
10 likes received 10 solutions authored 5 solutions authored
Hi Girish. Is this a new design using the TC1782? In the AURIX family (TC2xx or TC3xx), it's easy to implement dead-time control with the GTM or CCU6, but the TC1782 is before my time.
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