A5101596613- Silicon Carbide Semiconductor Technologies
- Multilevel Inverters and Converters
- HVDC Systems and Fault Protection
- Advanced DC-DC Converters
- Power System Reliability and Maintenance
- Electrical Fault Detection and Protection
- Semiconductor materials and devices
- Industrial Engineering and Technologies
- Cardiac Valve Diseases and Treatments
- Electric Power Systems and Control
- Photovoltaic System Optimization Techniques
- Cardiac pacing and defibrillation studies
- Elevator Systems and Control
- Microgrid Control and Optimization
- Advancements in Semiconductor Devices and Circuit Design
- Electromagnetic Compatibility and Noise Suppression
- Cardiac Arrhythmias and Treatments
Kiel University
2018-2021
Universidade Federal de Minas Gerais
2017-2020
In the metal industry, rolling is most widely used steel forming process to provide high production and control of final product. Rolling mills must be able change speed strip at same time that controlled within precise limits. Furthermore, this application has a severe load profile, with torque variations during lamination process. These characteristics include among classical mission critical industry applications (MCIA). addition cost/failure rate, have dynamic loading, making design...
Modular multilevel converters (MMC) are complex systems, composed of many elements, and exposed to critical load demands in some cases. Thereby, a detailed design its components is preeminent importance achieve high system-level reliability. However, the number devices challenges tradeoff between cost This article, introduces reliability-oriented methodology, based on predefined unreliability level (U <sub xmlns:mml="http://www.w3.org/1998/Math/MathML"...
Active thermal control has been introduced to regulate the steady state and reduce transient thermal-mechanical stress in power electronic modules. Specifically, it can equally distribute temperature among devices, thereby better distributing a set of devices reducing failure probability most thermally-stressed devices. This is great importance for multilevel topologies particular Neutral Point Clamped (NPC) topologies, which have an inherent unbalance same phase. In hybrid structures,...
This article proposes the minimum dc-link voltage control for efficiency and reliability improvement of two-stage grid-connected photovoltaic (PV) inverters. The main goal is to compute in real-time required power transfer reduce stresses on capacitors semiconductor devices. Analytical expressions current converter components are derived support viability technique. feasibility this strategy demonstrated by experimental results. system-level computed based a case study 3-kW commercial PV...
Mine hoist systems play a vital role in gold ore transportation. They are the connection between underground mine and beneficiation plant. As result, any system interruption compromises production. In this paper, it is proposed mission critical analysis design methodology for power converters order to achieve proper reliability of drive system. Since failure devices responsible significant portion total downtime converters, detailed study insulated gate bipolar transistor (IGBT) modules...
SiC devices have recently been demonstrated and utilized in many different multilevel topologies. Active neutral point clamped (ANPC) converter is one of those topologies, where the use can significantly increase power density reduce output filter size. In order to achieve this, control algorithm needs be tailored utilize advantages each device technology. Therefore, strategies which could produce optimum results for Si based ANPC might not choice hybrid configuration, are mixed. this paper,...
Although multichip systems (MCS) are the standard solution for high-power converters, uneven losses and thermal distribution affect unequal lifetime consumption. Many solutions have been proposed to mitigate these effects; however, critical deviations still observed, leading a reduction of overall MCS reliability. Therefore, this work proposes selective soft-switching (SS) approach, whereby turn-off devices manipulated obtain balancing increase reliability MCSs. As consequence, high current...
Steel is nowadays the world's most important industrial material, with over 1.5 billion tonnes produced annually. In metal industry, rolling widely used steel forming process to provide high production and control of final product. large drive systems for mills, requirements such as fast dynamic response overload capacity are achieved by using power converters in medium-voltage range. Among existing multilevel converters, Neutral Point Clamped (NPC) accepted industry Modular Multilevel...
Uma das principais causas de morbidade e mortalidade cardiovascular em todo o mundo são as valvulopatias. Assim, para reduzir esses índices, os estudos nessa área estão constante evolução.
The unbalanced operation of multiphase drives has been adopted for the fault-tolerance purpose in mission critical applications. However, higher number phases increases devices and probability thermal mismatches among them. Indeed, parametric mismatches, cross coupling, inhomogeneous cooling, uneven degradation have reported as root causes deviation power semiconductor devices. Consequently, a temperature subset provokes unevenness lifetime reduction whole converter. In modular systems,...
Redundancy strategies have been used to ensure continuity of service facing catastrophic failure events in power converters. However, additional parts are needed, resulting increased cost, size and weight. The increasing demand high density low-cost systems, motivates more reliable converters with few parts. This work, address the scientific question on which modular dc-dc converter shall be selected achieve a required residual minimum redundancy level. Smart Transformer is as case study for...
The Smart Transformers (ST) enables the use of dc-grid and voltage control both low-voltage medium-voltage (MV) network allowing higher penetration renewable new loads as EV charging stations without needing to reinforce grid. main challenge for ST is obtain high efficiency reliability, standard low-frequency transformers. Power routing based active thermal (ATC) has been proposed modular converters loading balance their consumed lifetimes. Nevertheless, it not applicable LV side ST, if only...
What are the root causes of recent live-line tool flashovers at electric field gradients less than 100 kV/m when tools supposed to withstand three times that stress?Computer simulations electrical discharges from head connected energized conductor suggest a role high-speed surface partial in initiating flashover process. Insulator Flashover Caused by Salt-ContaminatedSnowstorms-Lessons Snow Damage Japan