S6 - EMC for Emerging Power System

Session Chair

Dr Oskari Leppäaho

Product Architect, Functional Safety at Danfoss Drives

Biography

Oskari completed his B.Sc. (2014) and M.Sc. (2015) degrees from Tampere University of Technology (currently Tampere University) in Electrophysics. He received his Ph.D. (2023) degree from INSA Rennes.  He was a Main Circuit Development Engineer between 2013-2023 at Vacon Oy, Finland, which became part of Danfoss in 2014 with a short stint at Valeo in between (2020-2022) during his doctoral studies. Currently, he is a Product Architect at Danfoss Drives, Finland.

He stumbled upon EMC early in his master's studies, when he was searching for an interesting subject that would combine physics and electronics that were his main interests during bachelor studies. During his early career, he contributed to EMC design of Vacon 100 AC Drives and oversaw the EMC design for some of the models. Later, he got more responsibility outside EMC at Danfoss Drives, moved into the USA for a few years, and participated in various design tasks for iC7 product line. After spending some time in the US, it was time for him to come back to Europe to embark a Ph.D. degree in an EU-funded MSCA project PETER. In January 2023, he has returned to Danfoss Drives and has worked mostly with functional safety since mid-2023.

Mobile machines and vehicles have long trusted on fossil fuels as power source. However, climate change and worsening air quality in cities calls for action to limit fossil fuel usage. Electrification helps to cut emissions by increasing efficiency in vehicles both on land and at sea, with boldest attempting the same in air. This brings electric motors and their drives as well as other power conversion equipment to vehicles which have never seen them before. Optimized motor control cutting high voltages and currents thousands of times a second is a recipe for EMC problems if not treated right. In this session, different aspects and advances in EMC of electrification solutions are discussed to guide you through the EMC headaches of electrification.

Speaker 1

Dr Min Zhang

EMC Consultant, Mach One Design

A technical review of EMI filters for electrification

Speaker 2

Dr Oskari Leppäaho

Common mode voltage management in electrification solutions

Abstract

Many electrification solutions use power electronics including frequency converters to manage electric power flow through the system. In most of the cases, several converters are needed for a functioning system. These converters are often linked together from their DC-terminals to perform power sharing with direct current. While DC-sharing is very advantageous from total system cost and efficiency point of view, it generates a possibility for high frequency common mode voltage challenges due to multiple converters operating at the same time. This common mode voltage can be managed with different kinds of filtering solutions or through system-level planning. In this presentation, advantages and disadvantages of different filtering solutions are discussed through examples and their relation to system-level common mode voltage planning is highlighted. Once the basic cases have been covered, the second half of the presentation concentrates on practical examples with complex system scenarios, like redundant electric propulsion systems including load-sharing and shared peak-shaving capabilities.

Speaker 3

Simon Price

Principal EMC Engineer and Independent Safety Assessor, Castle EMC

Introduction to EMC and Electrical Systems Compatibility (ESC) for a locomotive re-traction project.  Provide an insight into the breadth and depth of a rolling stock ESC Safety Case for route acceptance.  Provide an overview of the simulation and testing works undertaken and zoom into a few interesting technical challenges.