Browsing by Author "Rahimpour, Saeed"

Filter results by typing the first few letters
Now showing 1 - 5 of 5
  • Fault Management Techniques to Enhance the Reliability of Power Electronic Converters: An Overview
    (2023-02-06) Rahimpour, Saeed; Husev, Oleksandr; Vinnikov, Dmitri; Kurdkandi, Naser Vosoughi; Tarzamni, Hadi
     A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
    The reliability of power electronic converters is a major concern in industrial applications because of using prone-to-failure elements such as high-power semiconductor devices and electronic capacitors. Hence, designing fault-tolerant inverters has been of great interest among researchers in both academia and industry over the last decade. Among the three stages of fault management, compensating the fault is the most important and challenging part. The techniques for fault compensation can be classified into three groups: hardware redundancy methods which use extra switches, legs, or modules to replace the faulty parts directly or indirectly, switching states redundancy methods which are about omitting and replacing the impossible switching states, and unbalance compensation including the techniques to compensate for the unbalances in the system caused by a fault. In this paper, an overview of fault-tolerant inverters is presented. A classification of fault-tolerant inverters is demonstrated and major cases in each of its categories are explained.
  • Mitigation of greenhouse gas (GHG) emissions aligned with global energy transition: Scenarios of elements use
    (2024-11) Bandpey, Atieh Fahimi; Rahimpour, Saeed; Kraslawski, Andrzej
     A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
    Several proposed technologies (e.g., renewables and carbon capture and storage (CCS)) to reduce GHG emissions face significant challenges like accessing critical raw materials. This study assesses the demand for 29 mineral elements in technologies. A dynamic material flow analysis model was applied to examine five global climate change mitigation scenarios to 2050. The scenarios selected are the Net Zero Emission (NZE), 1.5 °C, Announced Pledges (AP) and Stated Policy (STEP) for the year 2022, and the Sustainable Development (SD) for the year 2021. The results show that demand for tellurium will increase and cumulatively exceed current reserves in the AP, SD, NZE and 1.5 °C scenarios from 2022 to 2050, and demand for indium and cobalt will exceed reserves in NZE and 1.5 °C scenarios. In the STEP scenario, elements will not face shortages. The findings indicate that specific technology choices, such as the high use of thin-film solar photovoltaic (PV), can significantly impact demand for particular elements like tellurium. The results demonstrate that the selection of the technology and scenario for GHG mitigation considerably impacts element consumption. The novelty of this work consists of its supply-efficient approach to the element demand for technology in different energy sectors including in the energy generation, distribution, storage, and consumption sectors in each recent scenario. The results presented in this study could assist policymakers in the selection of technological solutions for climate change mitigation.
  • Operation and Design Consideration of an Ultra High Step-Up DC-DC Converter featuring High Power Density
    (2021-10-01) Tarzamni, Hadi; Sabahi, Mehran; Rahimpour, Saeed; Lehtonen, Matti; Dehghanian, Payman
     A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
    A new dual-coupled inductor (CI) single-switch high step-up dc-dc topology featuring high power density is proposed in this study. Various capacitive power transfer methods, as well as inductive power transfer techniques, are utilized to act as a more efficient power interface between the input and the load. Three ports in the output terminal are employed to distribute the overall output voltage, diminish the voltage ripple in high-voltage gain ratios, and decrease the voltage stress on the port component. In the proposed converter, first, the voltage gain is high in lower duty cycles of the switching. Second, the stored energy of magnetizing and leakage inductances is recycled in both Cls. Third, the switch voltage spikes are alleviated. Fourth, the operation is done with no circulating current. Fifth, low-size passive components are presented. Sixth, high power density is obtained, and the voltage range is widened. Finally, a simple pulsewidth modulation (PWM) utilizing a wide control range is provided. In this study, the steady-state operation is analyzed under both continuous conduction mode (CCM) and discontinuous conduction mode (DCM), and the performance of the converter is evaluated using comparisons with similar works. In addition, the experimental results have been provided to justify the feasibility of the design.
  • An Overview of Lifetime Management of Power Electronic Converters
    (2022) Rahimpour, Saeed; Tarzamni, Hadi; Kurdkandi, Naser Vosoughi; Husev, Oleksandr; Vinnikov, Dmitri; Tahami, Farzad
     A2 Katsausartikkeli tieteellisessä aikakauslehdessä
    An expected lifetime of converters is of great importance for optimal decision-making in the planning of modern Power Electronic (PE) systems. Hence, the lifetime management of power electronic systems has attracted a lot of attention in academia and industry. This paper is a guideline for managing the lifetime of power converters. Analyzing the different kinds of failures, failure modes and their corresponding mechanisms are investigated in the first section along with the failure data needed as input parameters of the assessment. In the second section, lifetime prediction in two aspects of component-level and system level is discussed and all the possible techniques to achieve them are investigated and compared. All the steps required to predict the lifetime in the component-level including electrothermal modeling, cycle counting, lifetime model, damage accumulation, parameter estimation, and lifetime distribution are described and then system level methods consisting of reliability block diagrams, fault-tree analysis, and Markov chains are examined and compared. The last section contains the roadmap of the lifetime extension including the reliable design and condition monitoring.
  • Selected social impact indicators influenced by materials for green energy technologies
    (2024-10-29) Rahimpour, Saeed; El-Wali, Mohammad; Makarava, Iryna; Tuomisto, Hanna L.; Lundström, Mari; Kraslawski, Andrzej
     A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
    The social risks of green energy transition are underexplored. One of the important questions is which materials used in green energy technologies offer the greatest social benefits, such as ensuring decent living conditions, and which pose the most social risks. To address this issue, we develop a dynamic material-energy flow model integrating system dynamics, social life cycle assessment, and geometallurgical approaches. The analysis focuses on critical materials: Rare Earth Elements, Nickel, Silicon, Graphite, Magnesium, Gallium, Germanium, Indium, Aluminum, Cobalt, Lithium, Zinc, and Tellurium used in wind turbines, electric vehicles, lithium-ion batteries and solar photovoltaic panels. We assess their social impact on work safety, gender equality, informal employment, labor income share, employment rate, and child labor—key issues addressed by Sustainable Development Goals 1, 5, and 8. Here we show that Aluminum production for electric vehicles, wind turbines and solar photovoltaic panels generates the most jobs and income opportunities, while extraction of Cobalt, Lithium, Silicon, and Zinc carry the highest social risks.