Dielectrics for Power Capacitors

High voltage capacitors are key components for transient storage and release of electrical energy in mobile electric devices, electric vehicles, stationary power systems and power transmission. Due to their high electric breakdown voltage, self-healing capability and affordability, polymer-based film capacitors are widely used, particularly those made from biaxially oriented polypropylene (BOPP). Their maximum operating temperature near 100°C, however, requires careful thermal management and oversize design. In high temperature applications well above 200°C, the preference shifts from organic to ceramic dielectric materials. Multilayer ceramic capacitors (MLCCs) are known for their excellent mechanical and thermal robustness, have a mature fabrication technology and have found a wide spectrum of applications in power electronic systems. Their higher cost level is frequently over-compensated by their robustness, a unique selling point particularly in high temperature applications. The present investigation...