1.2 Million Unit-hours Reached in Power Ring Life-Testing!

As part of the SBIR Phase II research grant, SBE is now testing 672 capacitors, with the purpose establish the reliability of SBE’s Power Ring capacitors.  We are currently at 1.2 million unit-hours and are still going!  The target is two million unit-hours. The actual end-results will be available in August 2010.  We expect that the end result will be a 1000μF capacitor, able to handle 100+Arms ripple current, and using 105°C Coolant, with 10-year reliability. 

The capacitors are tested in three batch ovens, 224 by oven.  These ovens have been custom designed for maximum temperature uniformity.  Each oven contains a rack specially designed not only to hold the capacitors during the lifetest, but also for production curing.  They will be used at our current facility to cure the film winding sections of the Power Rings as we ramp up production.  They will be then moved to our new facility.

Currently the three ovens are operating at different levels of temperature and applied.  The selections have been chosen to create a reliability matrix whereby a designer can pick a voltage, current, and power duty cycle, and then select the appropriate Power Ring to operate reliably for a given coolant temperature up to and including 105°C.  Outside the ovens are control modules, allowing us to monitor all of the capacitors’ temperatures and the constant health of each capacitor individually.
 
The temperature of each oven is monitored by a grid of eight thermocouples.  These thermocouples read the temperature every 15 seconds and these are recorded into a spreadsheet, along with a time stamp as an ongoing log of the test.

Read more on our 105°C Coolant DC Capacitor Research.