| Abstract [eng] |
Microsecond high magnetic field shaped pulse generators are investigated in the dissertation. High magnetic field technologies, circuit transition processes and the pulse shaping technique are analysed. Two prototypes of the high magnetic field generators are developed, one of them with asymmetric pulse shape with amplitude over 10 T, the rise time of 200 µs and decay time of 800 µs was applied for express calibration of the magnetic field sensors. Another generator generates repetitive microsecond high magnetic field square shaped pulses with amplitude up to 5 T and duration of 3–25 µs. Such generator has been applied to investigate the response of the biological objects to high-pulsed magnetic fields. The dissertation consists of three parts including introduction, 3 chapters, conclusions and references. The introduction reveals the investigated problem, importance of the thesis and the object of research and describes the purpose and tasks of the paper, research methodology, scientific novelty, the practical significance of results examined in the paper and defended statements. Author’s publications on the subject of the dissertation and conference presentations are supplied. Chapter 1 revises scientific articles related to the subject of the dissertation. The analysis of the magnetic field generation technology, devices used in magnetic field generators and microinductors are presented. The behaviour of the manganite and biological materials in high-pulsed magnetic fields are described. Conclusions and the tasks of dissertation are formed. Chapter 2 describes the structure of the high magnetic field generators prototypes. High magnetic field generator, consisting from capacitor bank, crowbar circuit and SCR switch is presented. Magnetic field distribution and Joule heating in multilayer inductors are analysed. High repetitive magnetic field generator based on MOSFET switch is presented. Transient processes in generator circuits are analysed. Microinductor field distribution and Joule heating are presented. Conclusions are formed. Chapters 3 is focused on the investigation of the magnetoresistive magnetic field sensors and the biological objects behaviour in the microsecond pulsed magnetic fields. The experimental results of the express calibration using one pulse technique of the magnetoresistive sensors and biological objects response in high magnetic fields are presented. Research results related to the dissertation subject are published in 7 scientific articles; 5 articles – in Thomson Reuters Web of Science database journals with impact factor, 2 – in others international (IndexCopernicus and IEEE/IEE) database journals, 7 presentations on the subject have been done in the conferences at national and international level. |
