Browsing by Author "Azuaje-Berbeci, Bernardo J."

Now showing 1 - 3 of 3

Citation - WoS: 3
Citation - Scopus: 5
Designing High Power Density Induction Motors for Electric Propulsion
(Ieee, 2022) Ertan, H. Bulent; Siddique, M. Salik; Koushan, Salar; Azuaje-Berbeci, Bernardo J.
Designing high-power-density electric motors for propulsion has become an increasingly important issue in the past few decades. This is not only because electric vehicles are projected to become the main private transportation means in near future, but also because of the ever so important metro and railway transport requirements. Along with these application areas, electric aircraft propulsion is also coming into focus in recent years. Electric motors for traction are required to have high torque density, high efficiency over a wide speed range and are required to be robust. In recent years, permanent magnet (PM) motors became the favorite choice for such applications because of their higher efficiency than other types of motors. Increasing demand for permanent magnets is likely to cause supply problems. Therefore, permanent magnet-free alternative motor types are of much interest. In this paper, the authors present the design of a 125 kW induction motor for railway application. This design has 3-times the power density of a commercial induction motor. The designed motor is manufactured and its test results are used for establishing an accurate finite-element model for the prediction of its performance. This model is used to investigate the effect of magnetic loading choice, slot shape and magnetic material choice on the efficiency of the motor. It is shown that with the same basic dimensions the efficiency of the motor can be increased to 96% which is comparable with a similar size PM motor.
Driving Conditions Leading To Thermal Runaway in Li-Ion Battery EV's
(IEEE, 2024) Ertan, H. Bulent; Azuaje-Berbeci, Bernardo J.
The adoption of high-energy-density lithium-ion batteries (LIB) as the energy source in electric vehicles (EV) introduces significant safety concerns. Thermal runaway (TR), a self-accelerating rise in battery temperature resulting in catastrophic failure, is a significant safety concern. Cooling system failure within the EV's thermal management system is one of several factors that can trigger TR. Typically, TR is initiated by exceeding a critical temperature threshold under abusive conditions. Understanding the operating conditions that lead to the path of TR is essential for ensuring EV and occupant safety. Recently, a detailed electrochemical-thermal model that incorporates the chemical reactions within the battery until TR is introduced. This paper aims to illustrate how this model can be used to identify the conditions leading to TR under realistic EV driving scenarios. For this purpose, an Advisor/Matlab-based model of a hybrid EV is developed and verified by tests, is used to estimate the current required from the vehicle's battery pack at a given driving condition. This is followed by the prediction of battery thermal response using the mentioned finite-element-analysis-based battery model. Several scenarios are tested in this paper to determine whether TR occurs and to identify the factors contributing to TR. This study aids in comprehending the factors that contribute to TR and the development of preventative measures for battery management system design.
Citation - WoS: 25
Citation - Scopus: 24
A Model for the Prediction of Thermal Runaway in Lithium-Ion Batteries
(Elsevier, 2024) Azuaje-Berbeci, Bernardo J.; Ertan, H. Bulent
The increasing popularity of electric vehicles is driving research into lithium -ion batteries (LIBs). Thermal runaway (TR) in LIBs is a serious concern for the safe operation of these high-energy-density batteries that is yet to be overcome. A reliable model is needed to predict voltage variation, heat generation, temperature rise, and the process leading to TR of a LIB battery under its operating conditions (charging-discharging). Such a model can be used to design battery packs more resilient to thermal runaway or assess how a battery pack would perform under hazardous conditions. Furthermore, it can be used for generating a warning signal if there is a possibility of the battery going towards TR. This paper presents an approach to solving this problem, which is not currently well addressed in the literature. The approach adopted in this paper is based on a numerical analysis of a multilayered electrochemical-thermal model of LIB. Tuning the parameters of a LIB for accurate results from this numerical model is presented, as well as the details of the approach in the paper. Experiments are performed under several LIBs, and their voltage and surface temperature variations are measured under various operating conditions, including thermal runaway. The results of the experiments are compared with the predictions of the numerical simulations. An excellent agreement is observed with the experimental results, proving the accuracy of the proposed approach. This approach can be configured to give results in a few minutes. The paper also discusses how the developed approach can be used to create a TR warning during operating conditions or to change the mode of operation of a LIB before a hazard occurs.