“Active Gate Switching Control of IGBT to Improve Efficiency in High Power Density Converters” Thesis submitted in partial fulfilment of the requirement for the PhD degree issued by the Universitat Politècnica de Catalunya, in its Electronic Engineering Program

 “Active Gate Switching Control of IGBT to Improve Efficiency in High Power Density Converters” 

Thesis submitted in partial fulfilment of the requirement for the PhD degree issued by the Universitat Politècnica de Catalunya, in its Electronic Engineering Program 

by Hamidreza Ghorbani 

Director: Dr. Prof. Jose Luis Romeral Martinez Co-Director: Dr. Eng. Vicent Sala

Abstract 

Insulated gate bipolar transistor (IGBT) power semiconductors are widely employed in industrial applications. This power switch capability in high voltage blocking and high current-carrying has expanded its use in power electronics. However, efficiency improvement and reducing the size of products is one of main tasks of engineers in recent years. In order to achieve high-density power converters, attentions are focused on the use of fast IGBTs. Therefore, for achieving this desire the trend is designing more effective IGBT gate drivers. In gate drive (GD) controlling, the main issue is maintaining transient behavior of the MOS-channel switch in well condition; when it switches fast to reduce losses. It is well known that fast switching has a direct effect on the efficiency improvement; meanwhile, it is the major reason of appearing electromagnetic interference (EMI) problems in switched-mode power converters. Nowadays the most expectant of an active gate driver (AGD) is actively adjusting the switching transient through simple circuit implementation. Usually its performance is compared with the conventional gate driver (CGD) with fixed driving profile. As a result a proposed AGD has the capability of increasing the switching speed while minimizing the switching stress. Different novel active gate drivers (as feed-forward and closed-loop topologies) have been designed and analysed in this study. To improve the exist trade-off between switching losses and EMI problem, all effective factors on this trade-off are evaluated and considered in proposed solutions. Theoretical developments include proposed controlling methods and simulated efficiency of IGBTs switching control. The efficiency improvement has been pursued with considering EMI study in the proposed active gate controller. Experimental tests have been conducted to verify the design and validate the results. Beside technical aspects, cost study has also considered in the closed-loop GD. The proposed gate drivers are simple enough to allow its use in real industrial applications.

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https://upcommons.upc.edu/bitstream/handle/2117/168574/THG1de1.pdf

Návrh a realizace obousměrného DC/DC měniče Design and Realisation of Bidirectional DC/DC Converter By Bc. Antonín Tomšů -2016 VŠB – Technická univerzita Ostrava Fakulta elektrotechniky a informatiky Katedra elektroniky

Návrh a realizace obousměrného DC/DC měniče Design and Realisation of Bidirectional DC/DC Converter By Bc. Antonín Tomšů -2016 

VŠB – Technická univerzita Ostrava Fakulta elektrotechniky a informatiky Katedra elektroniky

 Abstract 

The diploma thesis deals with design and subsequent implementation of a bidirectional DC/DC converter. Theoretical part is an analysis of galvanic insulated inverters together with a description of the function of the peripheral circuit. Practical part deals with the dimensioning and selection of components for the implemented drive, which included a selection of IGBT transistors, exciters, design of medium-frequency transformer, capacitors, chokes, current and voltage sensors, calculation of the power dissipation and cooling. In the next part of the diploma thesis is verification of connection through simulation function in programming environment LTspice. The last part contains description of a laboratory model realized by the bidirectional DC / DC converter with a summary of the results.

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https://dspace.vsb.cz/bitstream/handle/10084/115788/TOM0106_FEI_N2649_2612T015_2016.pdf?sequence=1&isAllowed=y

Řídicí jednotka reverzibilního DC/DC měniče-Control Unit of Reversible DC/DC Converter-Bc. Michal Chudárek-VŠB- TECHNICKÁ UNIVERZITA OSTRAVA Fakulta elektroniky a informatiky Katedra elektroniky

 

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https://dspace.vsb.cz/bitstream/handle/10084/108550/CHU0009_FEI_N2649_2612T015_2015.pdf?sequence=1&isAllowed=y

THÈSE Pour obtenir le grade de DOCTEUR DE L’UNIVERSITÉ JEAN MONNET DE SAINT-ÉTIENNE Ecole Doctorale Sciences, Ingénierie, Santé : ED SIS 488 Discipline : Optique Photonique Hyperfréquence Présentée et soutenue publiquement le 26 Mars 2014 Par Khamis YOUSSOUF KHAMIS Modélisation des Transformateurs Planaires Intégrés

Summary 

The use of passive components has experienced significant growth in recent decades, particularly in the field of mobile telephony and embedded electronics. The work presented in this thesis is part of a project between the LT2C laboratories of UJM and Ampère of INSA LYON. The objective of this thesis is the modeling of signal micro-transformers used to isolate the power (Driver IC) and control (JFET or MOSFET) parts. The points addressed in this thesis are the choice of transformer structures which meet the project requirements, the development of a transformer model which takes into account in particular the losses and the evolution of the permeability of the magnetic material and the different capacitive couplings. . Simulations using HFSS were carried out in order to design the selected structures and validate the developed model. Manufacturing steps compatible with those of microelectronics were used to fabricate one-layer and two-layer prototypes of magnetic material with different configurations. A high frequency characterization (2MHz-200MHz) using the vector network analyzer was carried out and finally a comparative study between the simulation results and the measurement results is the subject of a presentation. 

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Farias Martins, Lais (2019) Modelling and Analysis of DC-DC Converters for Bidirectional EV Charging Applications. PhD thesis, University of Sheffield.

Farias Martins, Lais (2019) Modelling and Analysis of DC-DC Converters for Bidirectional EV Charging Applications. 

PhD thesis, University of Sheffield. 

 Abstract This thesis is focused on the modelling and analysis of DC-DC converter topologies used for bidirectional charging of electric vehicles. Bidirectional converters are used in vehicle-to-grid (V2G) systems to allow bidirectional power transfer between the vehicle and the grid. Following the investigation in the literature review of potential converter topologies used in V2G applications and modelling techniques, this research proposes the application of the cyclic-averaging method for analysis of the Dual Active Bridge, 4th order resonant CLLC converter, and series compensated Inductive Power Transfer (IPT) converter. First, the cyclic-averaging method is applied for analysis of a phase-shift modulated Dual Active Bridge converter (DAB). For implementation of the cyclic analysis, the operation of the converter is first analysed using a Spice simulation to determine the system’s operation modes and duty cycles. The cyclic-averaging model is validated against a Spice simulation and employed to predict the converter’s output and to perform harmonic analysis of the inductor current. Following the analysis of the DAB, a 4th order CLLC converter is evaluated considering frequency and phase-shift modulations. The cyclic-averaging model is derived to model the behaviour of the converter’s output and state-variables in steady state. Additionally, a Fundamental Mode Approximation (FMA) model and a novel piecewise-linear state-variable model are also implemented for comparison. The models obtained are validated using Spice and, for the phase-shift modulated converter, experimental results. Finally, the series compensated IPT converter is analysed considering operation under phase-shift modulation. A FMA model is derived and, using circuit transformation, the state-variable and cyclic-averaging models previously defined for the CLLC converter are adapted for the analysis of the IPT converter. A prototype is built for validation of the cyclic model. Overall, for all converters analysed in this research, the cyclic-averaging method showed good performance with considerably fast execution and accuracy similar to Spice simulations.

VIEW FULL TEXT: https://etheses.whiterose.ac.uk/26746/1/Thesis_final.pdf