Impact of power electronics packaging on the reliability of grid connected photovoltaic converters for outdoor applications

The purpose of a cruise control system is to accurately maintain the driverʹs desired set speed, without intervention from the driver, by actuating the throttle-accelerator pedal linkage. Over the past five years, owners of a particular cruise control have complained that it did not operate properly. Complaints ranged from not engaging upon command, to the cruise unexpectedly accelerating past the desired speed. A common thread among all the complaints was the intermittent nature of the problems. More than 96"/o of the reported failed modules removed from vehicles and returned to the company, passed bench tests. This paper presents a physics-of-failure process to identify, induce and analyze failure mechanisms causing intermittent failures, high warranty returns and cannot duplicate (CND) problems of the digital electronic cruise control module (CCM). In addition, we explain why the manufacturerʹs tests were not representative of the actual automotive environments, nor were they conducted in a manner to access actual failures. We conclude with a recommendation for a physics-of-failure approach for future product development. © 1999 Elsevier Science Ltd. All rights reserved.