WEGAI was contracted by Controllix to seismically qualify two 12.47kV Capacitor Banks to the City of Anaheim Specification.  In order to meet the requirement WEGAI prepared an FE model of the Capacitor Banks and determined a worst-case configuration to be analyzed. 

Capacitor Bank Exterior & Interior Walls and Frames

The exterior walls and internal framework are modeled in detail to ensure the dynamic characteristics of the system are properly represented.  The internal electrical components are modeled to propagate the loads due to component masses throughout the load path of the system.

 

Internal Components & Detailed FE Model of the Controllix Reactor

While typically capacitor banks with kV ratings below 38kV are considered “Inherently Acceptable” per the IEEE 693-2005 standard, the City of Anaheim requires that the bank be qualified by dynamic analysis.  Through modal analysis it was determined that the primary natural frequencies were 10.01 Hz in the X Direction and 13.89 in the Y direction resulting in higher loading than the prescribed “inherently acceptable” loading.  Due to the complex geometry of the system the Capacitor Banks were also evaluated using non-linear analysis techniques to ensure the loading to the structure was correct.

 

Primary X (Left) and Y (Right) Direction Mode Shapes