Study On Characteristic Of High Voltage Pulse Transformer With Open Magnetic Core

High voltage pulse transformer has been widely used in the fields of pulsed powertechnology. In recent years, the Tesla pulse transformer based on open magnetic core iswidely applied in pulse power equipment, it act more and more important roles onrepetitive frequency accelerators. High power, high repetitive frequency andcompactness are the important development trend for pulsed transformer. A pulsetransformer based on open magnetic core is developed in this paper, Theoreticalanalyses and experiments have been carried out to study the characteristic of the pulsetransformer. This work is of great importance to researches on pulse transformer basedon open magnetic core. The main contributions of this dissertation are listed as follows.1. A small high-voltage pulse transformer with open magnetic core is developed.1) Input port of the primary winding is located at the end of magnetic core, whichcould avoid coupling coefficient decrease caused by angular magnetization.2) Thedeveloped pulse transformer has a small size, whose maximal dimension is250×150mm in length and diameter respectively.3) Coupling coefficient of the transformer islarger than0.9.4) when the pulse transformer is used to charge a capacitor withcapacitance of52pF, the amplitude of output voltage of transformer reached as high as310kV and step-up ratio is1:163.2. Characteristic of the developed transformer was studied.1) A formula to calculate the inductance parameter of pulse transfer is derived, andeffect of current density distribution of primary winding on inductance parameter isanalyzed theoretically, and different coils are used as primary winding to prove thecorrectness of the theoretical results by experiment.2)Secondary capacitance of thecompact pulse generator based on Tesla transformer was calculated theoretically, and ananalytic expression was acquired.3) Experiments were also carried out to study thepulse response characteristic of the pulse transformer.3. Design of the capacitive divider and open cable attenuator.A capacitive divider with good response was developed to detect the output voltageof the transformer. Meanwhile, in order to solve the problem that capacitive dividerwith long cable has bad time response, a high-impedance attenuator based on open cableis developed. The attenuator has a response time of20ns, divider ratio35.5, and it isapplied in measurement.