New Flatness Measurement Method of Aluminum Electrolytic Capacitor Can for heat stabilization to PWM Converter

Aluminum electrolytic capacitors are the most applied passive components in power electronic systems. Load current of this DC-link capacitors in the PWM converters - which operate in the renewable applications - is similar to a bipolar square wave signal. Aluminum electrolytic capacitors lifespan highly depends on their core temperature, which affected by the current. The extended cathode connected to the inside of the can is responsible for cooling in general applications. In case of heat sink applications, heat dissipation happens through the bottom of the aluminum can, where the dissipated heat is in direct proportion with the surface of bottom. More dissipated heat may greatly increase the lifetime of the capacitor, making the flatness value of the can bottom critical. The paper briefly presents the basic construction of an Aluminum electrolytic capacitors and a new test bench where the capacitor current same as the modern renewable converters. Furthermore presents a novel flatness measurement method. This solution can replace the expensive 3D measurement equipment. In addition, the new method is the newest element of capacitor measurement automation system (MAS) where data acquisition and visualization are automated by LabViewbased software and introduce the influence of production methods on the flatness value of the capacitor.