Frequency-Dependent Pi Model of a Three-Core Submarine Cable for Time and Frequency Domain Analysis

In this paper, a Frequency-Dependent Pi Model (FDPi) of a three-core submarine cable is presented. The model is intended to be used for the representation of submarine cables in an Offshore Wind Power Plant (OWPP) scenario for both time and frequency domain analysis. The frequency-dependent variation of each conductive layer is modeled by a Foster equivalent network whose parameters are tuned by means of Vector Fitting (VF) algorithm. The complete formulation for the parameterization of the model is presented in detail, which allows an easy reproduction of the presented model. The validation of the model is performed via a comparison with a well-established reference model, the Universal Line Model (ULM) from PSCAD/EMTDC software. Two cable system case studies are presented. The first case study shows the response of the FDPi Model for a three-core submarine cable. On the other hand, the second case study depicts the response of three single-core underground cables laying in trefoil formation. This last case shows the applicability of the FDPi Model to other types of cable systems and indirectly validates the response of the aforementioned model with experimental results. Additionally, potential applications of the FDPi model are presented

Perspective Chapter: Thermal Runaway in Lithium-Ion Batteries

Lithium-ion batteries (LIBs) are becoming well established as a key component in the integration of renewable energies and in the development of electric vehicles. Nevertheless, they have a narrow safe operating area with regard to the voltage and temperature conditions at which these batteries can work. Outside this area, a series of chemical reactions take place that can lead to component degradation, reduced performance and even self-destruction. The phenomenon consisting of the sudden failure of an LIB, causing an abrupt temperature increase, is known as thermal runaway (TR) and is considered to be the most dangerous event that can occur in LIBs. Therefore, the safety of LIBs is one of the obstacles that this technology must overcome in order to continue to develop and become well established for uses in all types of applications. This chapter presents a detailed study of the general issues surrounding this phenomenon. The origin of the problem is identified, the causes are detailed as well as the phases prior to TR. An analysis is made of the most relevant factors influencing this phenomenon, and details are provided of detection, prevention and mitigation measures that could either prevent the TR or reduce the consequences

Temperature indicators and overtemperature detection in lithium-ion batteries based on electrochemical impedance spectroscopy

Lithium-ion batteries are the leading technology for energy storage systems due to their attractive advantages. However, the safety of lithium-ion batteries is a major concern, as their operating conditions are limited in terms of temperature, voltage and state of charge. Therefore, it is important to monitor the conditions of lithium-ion batteries to guarantee safe operation. To this end, in the present work, we analyze electrochemical impedance spectroscopy (EIS) as a tool to estimate the temperature of batteries. Overtemperature abuse tests from 25 °C to 140 °C are performed at various states of charge, and EIS measurements are obtained during the tests. The influence of temperature on cell impedance at different frequencies is analyzed and new findings are revealed. The real part of the impedance is identified to be the best indicator for cell temperature estimation by EIS. In addition, the best frequency to achieve accurate temperature monitoring, avoiding disturbances produced by state of charge variations, is proposed based on experimental results. Finally, EIS is proven to be a reliable technique for overtemperature and thermal runaway detection.This work is part of the projects PID2019-111262RB-I00, funded by MCIN/AEI/10.13039/501100011033/, TED2021-132457B-I00, funded by MCIN/AEI/10.13039/501100011033/ and by the European Union NextGenerationEU/PRTR, STARDUST (774094), funded by European Union’s Horizon 2020 research and innovation programme, HYBPLANT (0011-1411-2022- 000039), funded by Government of Navarre, and has also been supported by MCIN/AEI/10.13039/501100011033/ and by European Social Fund under a PhD scholarship (grant PRE2020-095314)

Onset of irreversible reactions in overcharging lithium-ion cells: an experimental and modeling approach

Lithium-ion batteries are energy storage systems used in an increasing number of applications. Due to their flammable materials, their use entails risks of fire and explosion. The study of the abuse operation of these batteries before reaching the thermal runaway is a relevant research topic to prevent safety issues. There are various studies in the bibliography providing exhaustive thermal studies of the safe operating area, as well as concerning the thermal runaway. However, the onset irreversible reactions, that take place at a SOC around 110%, have not been properly analyzed. We present in this contribution an experimental study of this onset reaction measured in pouch Li-ion cells under various conditions of charge current and temperature. We also propose a lumped-parameter thermal model for the cell, which allows a detailed characterization of this exothermic reaction. The results achieved in this contributions can be a key tool to prevent overcharge accidents that may arise due to malfunctioning of the battery charger or battery management system.This work is part of the projects PID2019-111262RB-I00, funded by MCIN/AEI/10.13039/501100011033/, TED2021-132457B-I00, funded by MCIN/AEI/10.13039/501100011033/ and by the European Union NextGenerationEU/PRTR, STARDUST (774094), funded by European Union's Horizon 2020 research and innovation programme, HYBPLANT (0011-1411-2022- 000039), funded by Government of Navarre, and has also been supported by MCIN/AEI/10.13039/501100011033/ and by European Social Fund under a PhD scholarship (grant PRE2020-095314)

CONTROLE VECTORIEL SANS CAPTEUR MECANIQUE D'UNE MACHINE ROUE ASYNCRHONE

The aim of this work consists in designing a vector control of a wheel induction motor without mechanical sensor. This machine is intended to be the propulsion for a new concept of electrical bus. The main characteristics of this application are the wide frequency working area and the avoid of the mechanical sensor. First of all, we have chosen the best structure of control for this application. After that, we have designed, realised and implemented in simulation the functions of the chosen control structure. Aftel' that, we have realised several real implementations (based on a digital signal process) and validations in several experimental drives: a low power one in laboratory and an analogical simulator, a high power drive and an electrical bus in enterprise. In these implementations we have found real time handicaps and problems issued of the bus working conditions. This work has been realised in collaboration with ALSTOM, specialised on electrical transport, associated in this case with Renault Vehicule Industriels and with Iveco.Le but de ce travail est de concevoir un contrôle vectoriel sans capteur mécanique d'un moteur roue asynchrone. Ce moteur est destiné à la propulsion d'un nouveau concept de bus électrique. Les principales caractéristiques de cette application sont la large plage de fréquence et le fonctionnement sans capteur mécanique. Nous avons premièrement choisi la structure de commande la mieux adaptée à cette application. Après, nous avons conçu, réalisé, et mis en place en simulation les fonctions de la structure de commande retenue. Ensuite, nous avons réalisé plusieurs implantations (basées sur un processeur de signal) et validations sur différents dispositifs expérimentaux: un banc de petit puissance au laboratoire, puis un simulateur analogique, un banc d'essai moteur roue et un véhicule démonstrateur chez l'industriel. Dans ces implantations nous avons rencontré les contraintes du fonctionnement en temps réel et celles dues proprement aux conditions imposées sur le mode de fonctionnement dans le véhicule. Ce travail s'est déroulé en collaboration avec un partenaire industriel ALSTOM, spécialiste de la traction électrique, associé pour ce projet à Renault Véhicules Industriels et à Iveco

CONTROLE VECTORIEL SANS CAPTEUR MECANIQUE D'UNE MACHINE ROUE ASYNCRHONE

The aim of this work consists in designing a vector control of a wheel induction motor without mechanical sensor. This machine is intended to be the propulsion for a new concept of electrical bus. The main characteristics of this application are the wide frequency working area and the avoid of the mechanical sensor. First of all, we have chosen the best structure of control for this application. After that, we have designed, realised and implemented in simulation the functions of the chosen control structure. Aftel' that, we have realised several real implementations (based on a digital signal process) and validations in several experimental drives: a low power one in laboratory and an analogical simulator, a high power drive and an electrical bus in enterprise. In these implementations we have found real time handicaps and problems issued of the bus working conditions. This work has been realised in collaboration with ALSTOM, specialised on electrical transport, associated in this case with Renault Vehicule Industriels and with Iveco.Le but de ce travail est de concevoir un contrôle vectoriel sans capteur mécanique d'un moteur roue asynchrone. Ce moteur est destiné à la propulsion d'un nouveau concept de bus électrique. Les principales caractéristiques de cette application sont la large plage de fréquence et le fonctionnement sans capteur mécanique. Nous avons premièrement choisi la structure de commande la mieux adaptée à cette application. Après, nous avons conçu, réalisé, et mis en place en simulation les fonctions de la structure de commande retenue. Ensuite, nous avons réalisé plusieurs implantations (basées sur un processeur de signal) et validations sur différents dispositifs expérimentaux: un banc de petit puissance au laboratoire, puis un simulateur analogique, un banc d'essai moteur roue et un véhicule démonstrateur chez l'industriel. Dans ces implantations nous avons rencontré les contraintes du fonctionnement en temps réel et celles dues proprement aux conditions imposées sur le mode de fonctionnement dans le véhicule. Ce travail s'est déroulé en collaboration avec un partenaire industriel ALSTOM, spécialiste de la traction électrique, associé pour ce projet à Renault Véhicules Industriels et à Iveco