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A Tesla-Blumlein PFL-Bipolar Pulsed Power Generator Laurent Pecastaing, Meng Wang

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A Tesla-Blumlein PFL-Bipolar Pulsed Power Generator Laurent Pecastaing, Meng Wang A Tesla-Blumlein PFL-Bipolar Pulsed Power Generator Laurent Pecastaing, Meng Wang To cite this version: Laurent Pecastaing, Meng Wang. A Tesla-Blumlein PFL-Bipolar Pulsed Power Generator. Electro- magnetism. Loughborough University, 2016. English. tel-02372305 HAL Id: tel-02372305 https://hal-univ-pau.archives-ouvertes.fr/tel-02372305 Submitted on 20 Nov 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Meng Wang A Tesla-Blumlein PFL-Bipolar Pulsed Power Generator by Meng Wang, MSc, BEng A Doctoral Thesis submitted in partial fulfilment of the requirements for the award of Doctor of Philosophy of Loughborough University, UK March 2016 © Meng Wang, 2016 Meng Wang Acknowledgements I would like to express my sincere gratitude and to acknowledge the assistance and continuous support received from my supervisor Professor Bucur Novac, who was a constant source of inspiration and expert advice during my research work. I am very fortunate to have been associated with him. Special thanks are also due to thank Professor Ivor Smith for his efforts and I am also grateful to him for his reviews and advice throughout the writing of the thesis. I am very grateful to Mr. Keith Stanley for his technical assistance in designing and constructing the experimental systems and his advice related to numerous mechanical problems. Without his help none of the systems described would have been built. I would also like to thank Mr. Peter Senior and other colleagues in the Plasma and Pulsed Power Group at Loughborough University, for providing friendly help. I must reserve a special thank you for my parents Mr. Xuemin Wang and Mrs Shegai Li who supported me during the course of this degree, without their support none of the work described would have been possible. I would like to thank my husband Mr. Long Yu for his unconditional constant support and patience during this period. He has shared all the achievements and frustrations. Finally, I would like to thank all my other friends who helped to keep my confidence up and to be there when I needed them. i Meng Wang Abstract A Tesla-Blumlein PFL-Bipolar pulsed power generator, has been successfully designed, manufactured and demonstrated. The compact Tesla transformer that it employs has successfully charged capacitive loads to peak voltages up to 0.6 MV with an overall energy efficiency in excess of 90% . The Tesla–driven Blumlein PFL generator is capable of producing a voltage impulse approaching 0.6 MV with a rise time close to 2 ns, generating a peak electrical power of up to 10 GW for 5 ns when connected to a 30 Ω resistive load. Potentially for medical application, a bipolar former has been designed and successfully implemented as an extension to the system and to enable the generation of a sinusoid-like voltage impulse with a peak-to-peak value reaching 650 kV and having a frequency bandwidth beyond 1 GHz. This thesis describes the application of various numerical techniques used to design a successful generator, such as filamentary modelling, electrostatic and transient (PSpice) circuit analysis, Computer Simulation Technology (CST) simulation. All the major parameters of both the Tesla transformer, the Blumlein pulse forming line and the bipolar former were determined, enabling accurate modelling of the overall unit to be performed. The wide bandwidth and ultrafast embedded sensors used to monitor the dynamic characteristics of the overall system are also presented. Experimental results obtained during this major experimental programme are compared with theoretical predictions and the way ahead towards connecting to an antenna for medical application is considered. ii Meng Wang List of Principal Symbols 퐿푝 primary inductance 퐿푠 secondary inductance 퐶푝 primary capacitance 퐶푠 secondary capacitance 푞푝 electric charge on primary capacitance 푞푠 electric charge on secondary capacitance 휔푝 resonant frequency of primary circuit 휔푠 resonant frequency of secondary circuit k coupling coefficient 휔1 angular resonant frequency of primary circuit 휔2 angular resonant frequency of secondary circuit η energy transfer efficiency 푄푝 quality factor of primary circuit 푄푠 quality factor of secondary circuit τ damping time constant 푀푖,푗 mutual inductance between the 푖푡ℎ and the 푗푡ℎ filaments 푟푝 inner radius of primary winding 푤푝 axial length of primary winding ℎ푝 thickness of primary winding δ skin depth 푝 푍푖 position in axis Z of primary filaments 푝 푅푖 position in axis R of primary filaments K(k) complete elliptic integral of the first kind E(k) complete elliptic integral of the second kind 푟푟 radius of secondary winding iii Meng Wang 푤푠 axial length of secondary winding p axial pitch of the former of secondary rings 푅푠0 radius to bottom of the first ring of secondary winding 푅푠29 radius to bottom of the last ring of secondary winding 푠 푍푖 position in axis Z of secondary filaments 푠 푅푖 position in axis R of secondary filaments 퐸푏 pulse breakdown voltage 푄푖 electric charge of 푖푡ℎ conductor 0 푉푗 potential of 푗푡ℎ conductor relative to conductor 0 퐵푖,푗 Maxwell coefficients between 푖푡ℎ conductor and 푗푡ℎ conductor 푟1 radius of Blumlein PFL outer cylinder 푟2 radius of Blumlein PFL middle cylinder 푟3 radius of Blumlein PFL inner cylinder 푍1 characteristic impedance of Blumlein PFL inner line 푍2 characteristic impedance of Blumlein PFL outer line 푍′ load impedance of Blumlein PFL 휀푟 relative permittivity of dielectric material 휇푟 relative permeability of dielectric material 푙퐵 length of Blumlein PFL v wave propagation velocity 휀0 permittivity of vacuum ρ resistivity of dielectric 푑1 diameter of bipolar former inner electrode 푑2 internal diameter of bipolar former intermediate electrode ′ 푑2 outer diameter of bipolar former intermediate electrode 푑3 internal diameter of bipolar former outer electrode 휆푐 cut-off wavelength iv Meng Wang 푓푐 cut-off frequency v Meng Wang Contents 1. Introduction ............................................................................................................. 1 1.1. Introduction to Pulsed Power technology ....................................................... 1 1.2. Literature review ............................................................................................. 3 History of Pulsed Power .................................................................... 3 Examples of outstanding pulsed power generators ............................ 5 1.3. Applications of Pulsed Power Technology ................................................... 11 1.4. Aim of the thesis ........................................................................................... 15 1.5. Outline of the thesis ....................................................................................... 16 1.6. References ..................................................................................................... 18 2. Tesla transformer .................................................................................................. 22 2.1. Introduction and history of Tesla transformers ............................................. 22 2.2. Tesla transformer theory ............................................................................... 26 Lossless circuit (푹풑 = 푹풔 = ퟎ) ....................................................... 29 Low-loss circuit ............................................................................... 31 2.3. Modelling of Tesla transformer ..................................................................... 34 Filamentary modelling ..................................................................... 34 Electrostatic modelling .................................................................... 43 2.4. References ..................................................................................................... 49 3. Blumlein pulse forming line ................................................................................. 54 3.1. Fundamentals of Blumlein pulse forming line .............................................. 54 vi Meng Wang Introduction of Blumlein pulse forming line ................................... 54 Circuit Analysis ............................................................................... 56 3.2. Design consideration and procedure ............................................................. 59 Design consideration ........................................................................ 59 Dielectric .......................................................................................... 60 Electrostatic modelling .................................................................... 62 3.3. Overall configuration and manufacture ......................................................... 64 3.4. References ..................................................................................................... 66 4. Bipolar former ....................................................................................................... 68 4.1. Introduction of bipolar former ....................................................................... 68 Motivation
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