Seminar on Humidity Robustness and Insulation Coordination for e-Mobility: Speaker Biographies & Abstracts
Sven Clausner is a Research Associate and PhD candidate at the University of Bremen at the Institute for Electrical Drives, Power Electronics and Devices (IALB). The focus of his research is humidity-related reliability of power electronic systems. He had background and training in areas related to energy systems and high voltage engineering. He holds a Master of Science degree in energy and automation systems with a focus on power electronics, and a Bachelor of Science in electrical engineering with a focus on high voltage engineering from Chemnitz University of Technology.
Abstract: Humidity Robustness of Insulation Materials Under High Voltage
This presentation explores the critical aspects of humidity robustness for power electronic systems exposed to high voltage, humidity and temperature. It aims to provide valuable insights into the challenges posed by humidity in high voltage environments and to highlight the significance of incorporating robust insulation materials to ensure the reliability and longevity of power modules.
Moisture intrusion poses a significant challenge in power modules, leading to various performance issues and potential failures. The High Voltage-High Humidity, High Temperature Reverse Bias (HV-H³TRB) test serves as a standard methodology for investigating humidity-driven issues in power electronic systems.
This presentation delves into the comprehensive examination of potential mechanisms induced by humidity, emphasizing the impact of corrosive gases and the role of Parylene coating in mitigating these effects. Condensation, another possible consequence of humidity exposure, is analyzed in the context of its influence on insulation performance. Additionally, the presentation extends to the examination of printed circuit boards (PCBs), exploring their susceptibility to humidity-induced degradation and proposing strategies for enhanced resilience.
Vivien Grau is a research engineer at Bosch Corporate Sector Research and Advance Engineering, where she works on reliability testing of power electronics and DC-link capacitors. Prior to joining Bosch, she was a research associate with the Institute for Power Electronics and Electrical Drives (ISEA), RWTH Aachen University, where she was a group leader for the electrical drives group and a postdoc. Her research focused mainly on the effects of steep voltage slopes of wide-bandgap semiconductor devices on insulation systems. Ms. Grau received M.Sc. and Ph.D. degrees in electrical engineering from the RWTH Aachen University in 2016 and 2021, respectively.
Abstract: Basics and Mechanisms of Isolation
- Insulation materials and breakdown mechanisms
- Influences on dielectric strength
Dipl.-Ing. (FH) Ove Hach studied electrical engineering at the University of Applied Sciences in Kiel from 1990 to 1994 after completing an apprenticeship as an electronics technician for power systems.
Abstract: Resistors in High Voltage Applications
- Robustness of SMD MELF resistors compared to SMD chip resistors
- Quality figures of resistors
- Criteria for resistor selection used in high voltage applications
- Vishay high voltage resistors
Andreas Karch is Technical Manager for Indium Corporation and Technologist – Advanced Applications. In this role, he provides technical support on solder paste and preforms, fluxes, and thermal management materials to Indium’s customers in Germany, Austria, and Switzerland. He has more than 20 years of automotive industry experience in PCB and power electronics, including the advanced development of customized electronics. He received an award for developing one of the top 10 innovative patents for automotive LED assembly. Mr. Karch is an ECQA-certified integrated design engineer and holds a Six Sigma Yellow Belt.
Abstract: No Clean Flux Residues in Automotive Applications Have to Meet Higher Requirements
Increased automotive electrification (48V, HEV, EV) and the subsequent utilization of high-power components such as DPAKs and power-QFNs in under-the-hood electronics (e.g., 48/12V DC-DC converter PCBA, voltage stabilizer PCBA for start-stop module), have caused the SIR (surface insulation resistance) specifications for evaluating the electrical reliability of no-clean solder paste flux chemistry to become more stringent. These changes include: test voltage increasing from 5V to 10-50V, test time increasing from 168 hours to 500-1000 hours, pitch decreasing from 0.5mm to 0.2-0.3mm; and minimum SIR threshold increasing from 100 MΩ to 500 MΩ.
No-clean solder pastes are normally used in automotive PCB assembly to solder low-standoff components such as DPAKs and power-QFNs (gap between the PCB pad and the component underbody is typically under 75µ). During reflow, volatiles in the flux chemistry such as activators and solvents boil off, but a lower standoff reduces the opportunity for the flux volatiles to vent, resulting in “wet” flux residue, post reflow. It is therefore critical that the no-clean flux residue does not cause ionic dendritic growth and corrosion under low-standoff power components, during the working life of the product.
This presentation reports on a study that looks at the influence of no-clean flux chemistries on the reliability of automotive PCB applications, especially failure mechanisms caused by dendritic growth for high-power, low-standoff components for enhanced SIR conditions. It was observed that certain no-clean flux chemistries clearly influence electrical reliability. The electrical reliability of the no-clean flux residue was not influenced by changes in the reflow profile with or without nitrogen.
Abstract: Technical Cleanliness Requirements of the Automotive Industry
- Requirements of high voltage electronics
- QV11738028 - BMWs quality standard on technical cleanliness
- Technical cleanliness across product life cycle
Stefan Schröder is currently Product Manager of conformal coatings for electronics globally. He joined Lackwerke Peters in 2000 as a field service engineer in the Application Technology Department for all coatings, starting with etch resists and solder masks for the PCB industry and also coatings and casting compounds for electronics. He studied at the University of Applied Sciences in Krefeld, Germany, and completed his studies of technical chemistry with a focus on coatings in 2000.
Johannes Tekath is Head of Research and Development for Lackwerke Peters. He joined the Peters research and development team in 1997, responsible for the development of innovative products for PCB production. Since 2021, he has led the research and development team at Peters, together with Detlev Schucht, focused on the company’s ELPEGUARD® products for the protection of electronics. He studied chemistry at the Fachhochschule Münster and finished his studies in 1997 as a chemical engineer specializing in polymer technologies.
Abstract: Insulation Materials for High Voltage ApplicationsProtective layers for electronics must fulfill increased requirements, especially driven by high voltage applications coming from e-mobility and renewable energies. The performance of conformal coatings must be considered with respect to the combination of climatic tests with high voltage bias. This presentation will show that conformal coatings perform well under high humidity and high temperature conditions even if high voltages of 1000 V bias are applied.
Dr. Helmut Schweigart is Head of Reliability & Surfaces for ZESTRON Europe. Prior to taking over this role in 2013, he managed the department of Application Technology, Processes and Technology. He is also involved with several industry groups. He serves as head of a working group and manager for the topic of corrosion protection of electronic assemblies for the GfKORR e.V. (Society for Corrosion Protection). He chairs the working party for climatic resistance testing at GUS e.V., and co-chairs the EFC (European Corrosion Federation) task group on corrosion in electronics. He has authored numerous papers, and serves as editor of the GfKORR handbooks for protective coating and potting of electronic assemblies.
Dr. Schweigart studied production and industrial engineering at the TU Munich, and subsequently received a PhD in Material Science for his research on the climatic reliability of protective-coated PCBAs.
Abstract: Overview of Challenges for Insulation Coordination
- High voltage failure mechanisms
- Gap of IEC 60664 specification
- Analytical approach to close the gap