@inproceedings{HopkinsHopfenspergerMellor, author = {Hopkins, Andrew and Hopfensperger, Bernhard and Mellor, Phil}, title = {DC-link Capacitor Reduction in Low Voltage and High Power Integrated Modular Motor Drives}, series = {2019 IEEE Energy Conversion Congress and Exposition (ECCE), 29 Sept.-3 Oct. 2019, Baltimore, MD, USA}, booktitle = {2019 IEEE Energy Conversion Congress and Exposition (ECCE), 29 Sept.-3 Oct. 2019, Baltimore, MD, USA}, doi = {10.1109/ECCE.2019.8913213}, pages = {3208 -- 3214}, abstract = {The development of 48V high power (>15 kW) automotive propulsion drives demands close integration of the power electronics and the electrical machine. Due to the large operating currents distributed multi-phase topologies are needed and physically separating the power converter from the e-machine would involve heavy cabling and costly connections. The volume and cost of the filter capacitor represents a major challenge in closely integrated high power integrated modular motor drives and techniques are needed to minimize this. The DC-link capacitor requires a large ripple current handling capability and cost, size and reliability limitations result in suitable candidate technologies being those with low volumetric energy densities. Use of interleaved multi three-phase machines are attractive due to the associated capacitor ripple current reduction. Discontinuous modulation schemes may also be employed as a technique for reducing the current ripple. In this paper techniques for capacitor ripple reduction are assessed through simulation and compared.}, language = {en} } @inproceedings{HopfenspergerDaubnerHerrmannetal., author = {Hopfensperger, Bernhard and Daubner, Andreas and Herrmann, Fabian and Hopkins, Andrew and Mellor, Phil}, title = {Investigation of Shifted PWM Methods for a Dual Three-Phase System to Reduce Capacitor RMS Current}, series = {PCIM Europe Digital Days 2020: International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management: 07.-08.07.2020, Online [proceedings]}, booktitle = {PCIM Europe Digital Days 2020: International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management: 07.-08.07.2020, Online [proceedings]}, publisher = {VDE-Verlag}, address = {Berlin, Offenbach}, isbn = {978-3-8007-5245-4}, pages = {124 -- 131}, abstract = {Mild hybrid automotive topologies containing a 48V high power (>15 kW) electric drive system demand a high integration of power electronics and electrical machine. A multi-phase motor winding topology helps to keep the per-phase operating currents to a reasonable level. Close integration and multi-phase system have led to a drive system with dual 3-phase systems supplied by a common 48V DC-link, which allows to shift PWM patterns for reduction of DC-link capacitor ripple current and size. This paper derives some basic rules for combinations of common PWM methods for dual 3-phase systems without magnetic cross-coupling. Experimental measurements verify simulated results.}, subject = {Elektroantrieb}, language = {en} } @inproceedings{HopfenspergerVanselowHopkinsetal., author = {Hopfensperger, Bernhard and Vanselow, Marcel and Hopkins, Andrew and Hahn, Ingo}, title = {Investigation of the Effect of Magnetic Coupling on the Capacitor Current of Dual Three-Phase Permanent Magnet Synchronous Machine Drives}, series = {2025 Energy Conversion Congress \& Expo Europe (ECCE Europe); Birmingham, United Kingdom ; 9/1/2025 - 9/4/2025}, booktitle = {2025 Energy Conversion Congress \& Expo Europe (ECCE Europe); Birmingham, United Kingdom ; 9/1/2025 - 9/4/2025}, publisher = {IEEE}, isbn = {979-8-3315-6752-1}, doi = {10.1109/ECCE-Europe62795.2025.11238664}, pages = {6}, abstract = {The drive towards electrification of vehicles and transport systems has led to research into multiphase drive topologies beyond the conventional three. Dual three-phase machine drives are attractive due to reduced torque and DC-link harmonic content in addition to fault tolerance. Further DC-link rms-current reductions can be realised by applying appropriate modulation schemes and shifting/interleaving PWM patterns. However, the magnetic cross coupling between the two three-phase systems impacts the output current harmonics and subsequently the torque ripple which is further exacerbated by interleaving of their respective carriers. The impact of magnetic coupling on the DC-link and output current ripples is investigated.}, language = {en} }