Everything You Wanted to Know about Capacitors but Were Afraid to Ask

Remember back in school when we learned about capacitors. The first thing we learned is that there are two types: polarized and non-polarized. The second lesson was, do not plug in polarized capacitors backward! After that, we moved on to inductors. As any engineer who has worked with capacitors knows, there is so much more to them.

The PSMA Capacitor Committee is organizing the first capacitor workshop at APEC 2018 in San Antonio, TX, the day before the conference begins, Saturday March 3, 2018. The workshop's title sets the tone for the packaged day: "(Almost) Everything You Wanted to Know About Caps but Were Afraid to Ask."

Designers of dc-dc converters, frequency drives, inverters, and other power conversation applications will benefit from this workshop. The content is designed to introduce, or re-introduce, fundamentals of capacitor technologies and how they affect end user applications.

Unlike what we learned in school, there are more than two kinds of capacitors. The materials used to construct the dielectric and the electrodes, alter their characteristics and behavior. What happens when you replace the electrolyte in an aluminum capacitor? How does the film type change the self-healing of a film capacitor? Is it possible to avoid ceramics cracking on a PCB? These are the kinds of questions that will be addressed.

The workshop's organizing team is working on the presentations and structure now. The focus is on capacitor fundamentals, but not their basics. The agenda addresses the design of different capacitor types, how their characteristics change in your application, the effect of the operating environment, and considerations for their operational lifetime.

With capacitors being used across the electronics industry and in every electronic design, it is tough to create content that applies to every engineer at APEC. For this reason, the team is grouping content into three sessions.

Three technical content sessions are planned.

• Low Voltage. This course focuses on embedded or low voltage type applications. The most common example are DC-to-DC converters. Low voltage includes applications using less than 100 VDC. These applications could be 48 V automotive, 48 V data center, 12 V distribution, or lower voltage rails for microprocessors and FPGAs.
• High Voltage / Power. This session focuses on motor drives, inverters, and AC Line related applications.  Much focus will be on considerations when choosing a capacitor technology for DC Link applications.
• Failure Modes. Understanding how a capacitor, or any device, fail means you can design to avoid it.

In addition to the formal technical sessions, there will be several keynote presentations, and an interactive applications session. During breakfast, lunch and the end-of-day networking period there will be demonstrations of products, technologies, equipment, and measurements.

Presentations are designed to answer questions engineers have, or will have, when working with different capacitor dielectrics. As we finalize topics, the organizing committee is eager to hear additional topic suggestions.  Please contact Pierre Lohrber (pierre.lohrber@we-online.de) or James Lewis (jameslewis@kemet.com) of the organizing committee.

The latest agenda, registration, and additional information will be available at http://www.psma.com/technical-forums/capacitor/workshop.

The PSMA Capacitor committee will also be holding a half day Industry Session during APEC 2018. The topic for this session is focused on new capacitor technologies and products. The Industry session will start, where the workshops ends to help guide you through new capacitor developments and solutions for your specific applications.

• Fred Weber, Future Technology Worldwide
• Pierre Lohrber, Wurth Electronics
• James Lewis, KEMET Electronics

If you or anyone in your company is interested in getting on the distribution list for future issues of PSMA UPDATE, please send e-mail to: power@psma.com. Be sure to include your name and the name of your company.