{"title":"Capacitor sizing of three-level neutral point clamped voltage source inverter for electric vehicles: Effects of modulation and motor characteristics","authors":"Serhat Emir Ogan, Emine Bostanci","doi":"10.1049/pel2.12665","DOIUrl":null,"url":null,"abstract":"<p>A three-level neutral point clamped (3L-NPC) voltage source inverter (VSI) topology can be advantageous in electric vehicles with a high DC-link voltage and a high switching frequency. A bulky DC-link capacitor is not an option; thus, the DC-link capacitor's sizing considering the traction system characteristics is an important design step. This paper investigates how the DC-link capacitor size of a 3L-NPC VSI gets affected by the combination of the interdependent characteristics of an electric drive, such as its power factor, modulation index, current, and fundamental frequency, with the effects of the modulation methods. Five pulse width modulation (PWM) methods, of which three of them have an active neutral point potential control, are compared in terms of their neutral point potential (NPP) oscillations. Then, the size of the DC-link capacitor is determined for each PWM method so that the NPP ripple is kept under desired limits at all operating conditions. It is shown that both the modulation technique and the electric machine characteristics influence the capacitor size. For example, electric machine design modifications can introduce more than a 30% reduction in capacitor size. Finally, DC-link and NPP oscillations with different PWM methods are experimentally validated in a scaled-down 3L-NPC inverter.</p>","PeriodicalId":56302,"journal":{"name":"IET Power Electronics","volume":"17 9","pages":"1051-1066"},"PeriodicalIF":1.7000,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/pel2.12665","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"IET Power Electronics","FirstCategoryId":"5","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1049/pel2.12665","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ENGINEERING, ELECTRICAL & ELECTRONIC","Score":null,"Total":0}
引用次数: 0
Abstract
A three-level neutral point clamped (3L-NPC) voltage source inverter (VSI) topology can be advantageous in electric vehicles with a high DC-link voltage and a high switching frequency. A bulky DC-link capacitor is not an option; thus, the DC-link capacitor's sizing considering the traction system characteristics is an important design step. This paper investigates how the DC-link capacitor size of a 3L-NPC VSI gets affected by the combination of the interdependent characteristics of an electric drive, such as its power factor, modulation index, current, and fundamental frequency, with the effects of the modulation methods. Five pulse width modulation (PWM) methods, of which three of them have an active neutral point potential control, are compared in terms of their neutral point potential (NPP) oscillations. Then, the size of the DC-link capacitor is determined for each PWM method so that the NPP ripple is kept under desired limits at all operating conditions. It is shown that both the modulation technique and the electric machine characteristics influence the capacitor size. For example, electric machine design modifications can introduce more than a 30% reduction in capacitor size. Finally, DC-link and NPP oscillations with different PWM methods are experimentally validated in a scaled-down 3L-NPC inverter.
期刊介绍:
IET Power Electronics aims to attract original research papers, short communications, review articles and power electronics related educational studies. The scope covers applications and technologies in the field of power electronics with special focus on cost-effective, efficient, power dense, environmental friendly and robust solutions, which includes:
Applications:
Electric drives/generators, renewable energy, industrial and consumable applications (including lighting, welding, heating, sub-sea applications, drilling and others), medical and military apparatus, utility applications, transport and space application, energy harvesting, telecommunications, energy storage management systems, home appliances.
Technologies:
Circuits: all type of converter topologies for low and high power applications including but not limited to: inverter, rectifier, dc/dc converter, power supplies, UPS, ac/ac converter, resonant converter, high frequency converter, hybrid converter, multilevel converter, power factor correction circuits and other advanced topologies.
Components and Materials: switching devices and their control, inductors, sensors, transformers, capacitors, resistors, thermal management, filters, fuses and protection elements and other novel low-cost efficient components/materials.
Control: techniques for controlling, analysing, modelling and/or simulation of power electronics circuits and complete power electronics systems.
Design/Manufacturing/Testing: new multi-domain modelling, assembling and packaging technologies, advanced testing techniques.
Environmental Impact: Electromagnetic Interference (EMI) reduction techniques, Electromagnetic Compatibility (EMC), limiting acoustic noise and vibration, recycling techniques, use of non-rare material.
Education: teaching methods, programme and course design, use of technology in power electronics teaching, virtual laboratory and e-learning and fields within the scope of interest.
Special Issues. Current Call for papers:
Harmonic Mitigation Techniques and Grid Robustness in Power Electronic-Based Power Systems - https://digital-library.theiet.org/files/IET_PEL_CFP_HMTGRPEPS.pdf