High temperature capacitors with high energy density

Abstract

Power electronics are a key technology for hybrid and plug-in electric drive vehicles (EDV) and represent 20% of the material costs. DC bus capacitors are one of the critical components in EDV power inverters and they can occupy ~35% of the inverter volume, contribute to ~23% of the weight, and add ~25% of the cost. Current polypropylene (PP) film capacitors have dielectric constant K of 2.2 and temperature stability lower than 105 °C. We recently developed a modified Polyvinylidene fluoride (PVDF) which combines high dielectric constant, low dielectric loss, low leakage current, high dielectric breakdown strength, and high temperature stability. The modified PVDF capacitor film also has graceful failure feature which is critical to applications demanding high reliability and long lifetime. The thermoplastic nature of the modified PVDF ensures that they can be processed into thin capacitor film using inexpensive melt extrusion and biaxial orientation process. In this report, DSC and dielectric spectroscope test results of the novel capacitor film will be presented.

Faults in Modular Multilevel Cascade Converters—Part I: Reliability, Failure Mechanisms, and Fault Impact Analysis

“…Power capacitors are the second most critical component in power electronics systems [136]. As central part of each power cell, faults in the capacitors have significant impact on the MMCC operation.…”

Evaluación de la fuga de corriente en capacitores electrolíticos mediante dos procesos de envejecido

“…La mayoría de las investigaciones, se han enfocado en evaluar el rendimiento de los capacitores en condiciones extremas de temperatura y humedad, que incluían configuraciones de voltajes y corrientes de trabajo exigentes. Los resultados obtenidos han permitido mejorar los procesos productivos con un impacto positivo en las propiedades (físicas, térmicas, eléctricas y mecánicas) de los CET (Wang, 2020;Zou, 2012;Trainer, 2001;Chaneliere, 1998).…”

Experimental Comparisons and Evaluations of Different Types of DC-link Capacitors for VSI-Based Electric Compressors in Battery Electric Vehicle Systems

“…The MPPF-Cap has an operational lifetime more than ten times compared with Al-Caps. Then, the cost of replacement will outweigh the price difference between the different types of capacitors [9].…”

“…The MPPF-Cap has an operational lifetime more than ten times compared with Al-Caps. Then, the cost of replacement will outweigh the price difference between the different types of capacitors [9]. Figure 1 shows a block diagram of an electric vehicle with Full Automatic Temperature Control (FATC), which is a focus of study.…”