Fase Anizdun bihurgailuentzako modulazio berriak

266 p.Los convertidores multifase han adquirido una gran relevancia debido a sus ventajas sobre los convertidores trifásicos convencionales. Debido a estas ventajas, destacando la tolerancia a fallos, los sistemas multifase se emplean cada vez más en aplicaciones donde la fiabilidad es un factor clave. Sin embargo, estos sistemas no son inmunes a las faltas y, por ello, deben tomarse medidas que aumenten su fiabilidad y robustez. En concreto, esta tesis hace frente a dos de los mayores causantes de faltas en los sistemas basados en motores eléctricos (las faltas por circuito abierto y las faltas en los rodamientos debido a la tensión del modo común) mediante el uso de técnicas de modulación. Por un lado, en caso de perder una de las fases, las técnicas de modulación permiten generar tensiones equilibradas a la salida del convertidor, permitiendo a su vez que el convertidor siga funcionando aunque de forma degradada. Por otro lado, la tensión de modo común generada debido a la conmutación de los dispositivos que forman el convertidor daña los rodamientos de la máquina eléctrica. Por ello, siendo los rodamientos una pieza clave del motor, es necesario desarrollar nuevas técnicas de modulación que minimicen los efectos de la tensión de modo común. De esta forma, esta tesis, además de analizar en profundidad las fuentes causantes de las faltas mencionadas, propone nuevas técnicas de modulación capaces de mejorar el comportamiento del convertidor ante dichos problemas, con el fin de mejorar la tolerancia a fallos del convertidor y alargar la vida útil de los rodamientos del motor

The role of power device technology in the electric vehicle powertrain

In the automotive industry, the design and implementation of power converters and especially inverters, are at a turning point. Silicon (Si) IGBTs are at present the most widely used power semiconductors in most commercial vehicles. However, this trend is beginning to change with the appearance of wide-bandgap (WBG) devices, particularly silicon carbide (SiC) and gallium nitride (GaN). It is therefore advisable to review their main features and advantages, to update the degree of their market penetration, and to identify the most commonly used alternatives in automotive inverters. In this paper, the aim is therefore to summarize the most relevant characteristics of power inverters, reviewing and providing a global overview of the most outstanding aspects (packages, semiconductor internal structure, stack-ups, thermal considerations, etc.) of Si, SiC, and GaN power semiconductor technologies, and the degree of their use in electric vehicle powertrains. In addition, the paper also points out the trends that semiconductor technology and next-generation inverters will be likely to follow, especially when future prospects point to the use of “800 V" battery systems and increased switching frequencies. The internal structure and the characteristics of the power modules are disaggregated, highlighting their thermal and electrical characteristics. In addition, aspects relating to reliability are considered, at both the discrete device and power module level, as well as more general issues that involve the entire propulsion system, such as common-mode voltage.This work has been supported in part by the Government of the Basque Country through the fund for research groups of the Basque University System IT1440-22 and the Ministerio de Ciencia e Innovación of Spain as part of project PID2020-115126RB-I00 and FEDER funds. Finally, the collaboration of Yole Développement (Yole) is appreciated for providing updated data on its resources

Proposal of Hybrid Discontinuous PWM Technique for Five-Phase Inverters under Open-Phase Fault Operation

One of the most common issues in inverters are open-circuit faults (OPF). In this scenario, a proper fault-tolerant technique must be used to improve the motor performance. Although basic fault-tolerant modulation techniques are normally preferred, this paper proposes a discontinuous pulse-width modulation algorithm (HD-PWM) to operate five-phase inverters under a single OPF. In particular, loss equalization between the remaining switches after a fault occurs is the main objective of the HD-PWM algorithm, thus preventing future faults from occurring. The efficiency and harmonic distortion of the proposed technique are compared to the well-known sinusoidal PWM by simulation and experimentation under OPF conditions. The results obtained show a great performance of the proposed modulation technique, obtaining a relevant efficiency improvement.This work has been supported in part by the Government of the Basque Country within the fund for research groups of the Basque University system IT1440-22 and the MCIN/AEI/10.13039/501100011033 within the project PID2020-115126RB-I00

Common-Mode Voltage Elimination in Multilevel Power Inverter-Based Motor Drive Applications

[EN] The industry and academia are focusing their efforts on finding more efficient and reliable electrical machines and motor drives. However, many of the motors driven by pulse-width modulated converters face the recurring problem of common-mode voltage (CMV). In fact, this voltage leads to other problems such as bearing breakdown, deterioration of the stator winding insulation and electromagnetic interferences (EMI) that can affect the lifespan and correct operation of the motors. In this sense, multilevel converters have proven to be a useful tool for solving these problems and mitigating CMV over the past few decades. Among other reasons, because they provide additional degrees of freedom when comparing with two-level converters. However, although there are several proposals in the scientific literature on this topic, no complete information has been reviewed about the CMV issues and the different multilevel alternatives that can be used to solve it. In this context, the objective of this work is to determine how multilevel power converters provide additional degrees of freedom to make the reduction of the CMV possible by using specific modulation techniques, making it easier for engineers and scientists in this field to find solutions to this problem. This document consists of a descriptive study that collects the strengths and weaknesses of most important multilevel power converters, with special emphasis on how CMV affects each of them. In addition, the differences of modulation techniques aimed to the CMV reduction are explained in terms of output voltage, operating linear range, and generated CMV. Considering this last, it is recommended to use those modulation techniques that allow the generation of CMV levels of 0 V in order to be able to completely eliminate said voltage.This work was supported in part by the Government of the Basque Country within the Fund for Research Groups of the Basque University System under Grant IT978-16; in part by the Research Program ELKARTEK under Project ENSOL2-KK-2020/00077; in part by the Secretaria d'Universitats i Recerca del Departament d'Empresa i Coneixement de la Generalitat de Catalunya; in part by the Ministerio de Ciencia, Innovacion y Universidades of Spain under Project PID2019-111420RB-I00 and Project PID2020-115126RB-I00; and in part by the FEDER Funds

A 3D Reduced Common Mode Voltage PWM Algorithm for a Five-Phase Six-Leg Inverter

Neutral point voltage control converters (NPVCC) are being considered for AC drive applications, where their additional degree of freedom can be used for different purposes, such as fault tolerance or common mode voltage (CMV) reduction. For every PWM-driven converter, the CMV is an issue that must be considered since it can lead to shaft voltages between rotor and stator windings, generating bearing currents that accelerate bearing degradation, and can also produce a high level of electromagnetic interference (EMI). In light of these considerations, in this paper a three-dimensional reduced common mode voltage PWM (3D RCMV-PWM) technique is proposed which effectively reduces CMV in five-phase six-leg NPVCCs. The mathematical description of both the converter and the modulation technique, in space-vector and carrier-based approaches, is included. Furthermore, the simulation and experimental analysis validate the CMV reduction capability in addition to the good behaviour in terms of the efficiency and harmonic distortion of the proposed RCMV-PWM algorithm.This work has been supported in part by the Government of Basque Country within the fund for research groups of the Basque University system IT1440-22 and MCIN/AEI/10.13039/ 501100011033 within the project PID2020-115126RB-I00

Modu-komuneko tentsioa: ibilgailu elektrikoen isilpeko etsai

Guztion ahotan dauden ezaugarriak dira ibilgailu elektrikoen autonomia, bateriak kargatzeko denbora edota kostua. Baina zer gertatzen da ibilgailuen fidagarritasunarekin? Zer faktorek eragin dezakete ibilgailu elektriko bat matxuratzea eta zirkulaziotik ateratzea? Besteak beste, publiko orokorrarentzat ezezaguna den baina espezialistek ongi ezagutzen duten arazo bati egin behar dio aurre ibilgailu elektriko baten propultsiosistemak: modu komuneko tentsioari

Ibilgailu elektrikoaren joera: 2030a helburu

Geroz eta ibilgailu elektriko gehiago ikusten ditugu kaleetan eta telebistako iragarkietan. Baina zenbat itxaron behar dugu ibilgailu elektriko bat erosteko? Errentagarriak dira? Merezi dute? Asko dira ibilgailu elektrikoaren inguruan sortzen diren galderak eta mesfidantzak. Artikulu honetan, ibilgailu elektrikoak barne hartzen dituen merkatu aldakor honen zenbait zalantza argitzen dira, begirada 2030ean jarrita

Diseño de una tarjeta de drivers para un inversor de potencia.

[EN]The purpose of this project is to design a system which improves the e ciency of power inverters. The project is focused in the analysis of the di erent power semiconductors (based on silicon, silicon carbide and gallium nitride) and driver applications. This system can be implemented in di erent future versions of power inverters and in many kind of applications like electrical vehicles. Other than that, it can be also implemented on any machinery requiring an inverter obtaining more energy and reduce manufacturing costs.[EU]Proiektu honen helburua potentzia inbertsoreen efizientzia hobetzeko sistema baten diseinua burutzea da. Proiektua erdieroale desberdinen (siliziozkoak, silizio karburozkoak eta galio nitrurozkoak) analisian eta driverren aplikazio desberdinetara bideratuta dago. Sistema hau potentzia inbertsoreen etorkizuneko bertsioetan inplementa daiteke eta aplikazio mota ugarietan, ibilgailu elektrikoetan adibidez. Horrez aparte, inbertsore bat behar duen edozein makinariatan implementa daiteke, energia gehiago lortuz eta fabrikazio kostua gutxituz.[ES]El objetivo de este proyecto es diseñar una tarjeta de drivers para un inversor de potencia. El proyecto está enfocado en el análisis de los diferentes semiconductores (basados en silicio, carburo de silicio y nitruro de galio) y aplicaciones de los drivers. Este sistema puede implementarse en diferentes versiones futuras de inversores y en varios tipos de aplicaciones como los vehículos eléctricos. A parte de eso, puede ser implementado en cualquier maquinaria que requiera un inversor

Influence of PWM techniques on the DC-Link capacitor power losses of multiphase VSIs

In traction applications, particularly in transport electrification, multiphase drives are increasingly being an interesting alternative over their three-phase counterparts due to a range of advantages outweighing the additional cost, e.g. smoother torque performance, higher current capability, enhanced fault tolerance, higher efficiency and lower DC-Link current ripples. This work focuses on the impact this multiphase drives modulated by continuous and discontinuous PWM techniques have in a such a pricey and bulky component as it is the DC-Link capacitor. Taking into account that the equivalent series resistance of the DC-Link capacitor varies with frequency, the typical approximated calculation of the power losses in this component by means of the RMS value of the current is often inaccurate. Therefore, the spectral analysis of the DC-Link current has been carried out for the five-phase two-level VSI in order to estimate more accurately the power losses in the DC-Link capacitor and see which PWM modulation technique benefits this bulky and expensive component depending on its ESR curve and the selected switching frequency. Index Terms—Multiphase, DC-Link capacitor, DC-Link current spectrum, PWM modulation, ESR, power loss.This work has been supported in part by the Government of the Basque Country within the fund for research groups of the Basque University system IT978-16 and the research program ELKARTEK (project ENSOL2-KK-2020/00077) and the MCIN/AEI/10.13039/501100011033 within the project PID2020-115126RB-I00, as well as the support of the UPV/EHU pre-doctoral programme (PIF20-305)

Mitigation of Common Mode Voltage Issues in Electric Vehicle Drive Systems by Means of an Alternative AC-Decoupling Power Converter Topology

Electric vehicles (EV) are gaining popularity due to current environmental concerns. The electric drive, which is constituted by a power converter and an electric machine, is one of the main elements of the EV. Such machines suffer from common mode voltage (CMV) effects. The CMV introduces leakage currents through the bearings, leading to premature failures and reducing the propulsion system life cycles. As future EV power converters will rely on wide bandgap semiconductors with high switching frequency operation, CMV problems will become more prevalent, making the research on CMV mitigation strategies more relevant. A variety of CMV reduction methods can be found in the scientific literature, such as the inclusion of dedicated filters and the implementation of specific modulation techniques. However, alternative power converter topologies can also be introduced for CMV mitigation. The majority of such power converters for CMV mitigation are single-phase topologies intended for photovoltaic applications; thus, solutions in the form of three-phase topologies that could be applied to EVs are very limited. Considering all these, this paper proposes alternative three-phase topologies that could be exploited in EV applications. Their performance is compared with other existing proposals, providing a clear picture of the available alternatives, emphasizing their merits and drawbacks. From this comprehensive study, the benefits of a novel AC-decoupling topology is demonstrated. Moreover, an adequate modulation technique is also investigated in order to exploit the benefits of this topology while considering a trade-off between CMV mitigation, efficiency, and total harmonic distortion (THD). In order to extend the results of the study close to the real application, the performance of the proposed AC-decoupling topology is simulated using a complete and accurate EV model (including vehicle dynamics and a detailed propulsion system model) by means of state-of-the-art digital real-time simulation.This work was supported in part by the Government of the Basque Country within the fund for research groups of the Basque University System IT978-16 and in part by the Government of the Basque Country within the research program ELKARTEK as the project ENSOL(KK-2018/00040)