Mentor integrates automotive IGBT test and simulation
Mentor Graphics has launched a new power tester specifically for the automotive market that will also cut simulation errors from 20% to just 0.5% when used in conjunction with the company’s thermal software.
The MicReD Industrial Power Tester 600A has been added to the family based on feedback from automotive users of earlier products and in the light of projections that see automotive sales of IGBTs rising from $1B today to around $3B by 2020*.
Meanwhile, recalls due to the threat of overheating in the electrical and electronic systems of electric and hybrid-electric vehicles have been on the rise with, for example, both Ford and Tesla suffering them since 2014.
Increased capacity, finer calibration
For the tester itself, Mentor’s new MicReD product has been tweaked in several ways to meet the requirements of carmakers and their tier one suppliers. For example, the company has actually taken out the standard cooling solution and now allows user to insert their, reflecting the range of strategies different automotive OEMs apply (e.g., cold plate, direct liquid cooling).
The new member of the MicReD family specifically targets automotive IGBT test (Mentor Graphics)
However, a more eye-catching innovation is arguably the link Mentor has developed between the MicReD tester and its simulation products, Flowmaster for 1D thermo-fluid simulation and FloTHERM & FloEFD for component cooling CFD simulation.
Using MicReD, developers can power cycle 16 IGBTs in a single unit and up to 128 IGBTs by chaining eight 600A models together. This not only exceeds the current AEC Q101 standard for 77 test parts per lot, but also produces a statistically-valid dataset to feed back into and calibrate the simulation tools much more finely. Hence Mentor’s claim that it can cut simulation errors to 0.5%.
The tester enables finer calibration for simulation reducing errors to 0.5% (Mentor Graphics)
IGBT test and simulation for the automotive market is complicated not only by the limits of calibration but also the number of usage scenarios for different driving styles, and the resulting power and heating pressures they place on components. These can be national scenarios or those that differentiate between driving on the highway and in the city.
Some drive cycle profiles automotive simulation must address (Mentor Graphics)
Across all these, OEMs need to account for both reliability and life cycles with accuracy given components that will also typically be expected to last for about a decade in place.
According to Andras Vass-Varnai, senior product manager in Mentor’s Mechanical Analysis division, “The main issues facing IGBTs in EVs and HEVs include wire bond degradation, metallization layer mismatch, solder fatigue and cracks in the die or substrate.”
Then there are the complicated heat transfer patterns within vehicles that are increasingly composed of systems of systems. Tens of thousands of tester cycles and complex simulation models are needed to address them all.
“We believe there is nothing like this [MicReD/Flotherm combination], an overall solution for both simulation and test,” said Dr R. Keith Hanna, director of marketing and product strategy for Mentor’s Mechanical Analysis division.
Automotive is proving a sweet spot for Mentor, with sales to that market achieving 20% year-on-year for the last five years.
Orders on the MicReD Power Tester 600A are being taken now with shipping scheduled to begin in Summer 2016. The product website provides further technical information both on the specific automotive features in the new launch and on the integration of simulation and test.
*Source: Yole Developpement, April 2016
