The Research On The Radiation Interference And Suppression Measures In Intense Pulse Current Environment

With the development of the technology of electromagnetic launch, the modularpulsed power source puts forward new requirements, miniaturization, modularization hasbecome the development direction of pulse power source technology. Development ofminiaturization, modularization makes the module storage density increases, so theinfluence of magnetic field generated inside the module in the discharge process will begreater. The charging power supply is an important part of the modular pulse power source,which is composed of main circuit, control and detection circuit. The main circuit, whichconsists of switching devices and magnetic components, is used to realize the powerprocessing and transformation of energy; The control circuit is used to control the switch,relay action, as well as to give the thyristor trigger signal; The detection circuit detects theinstantaneous values of charging voltage and current in the charging process and recordsthe inductor current waveform in the discharge process. Compared to the rest of the pulsepower source, these circuits are weak circuit loop, vulnerable to interference. This papermainly studies the interference of strong pulsed magnetic field which produced by the pulsereactor on the weak parts in pulse power source. The main research contents are as follows:First of all, this paper introduces the system composition and working process ofpulse power source, and analyzes the principle of pulse forming network（PFN）. Thecurrent waveform on the thyristor and reactor in PFN circuit are simulated. The currentspectrum and its spectral width are estimated by fast Fourier transformation.Secondly, the3D solid modeling and Simulation of pulsed reactor are given by usingthe finite element analysis software Ansoft Maxwell. For the simulation of the interferenceof pulse magnetic field on the weak part of the pulse power source when in normal work,the simplified circuit model of the PFN is loaded with impulse current as the radiationinterference source. And by using the radiation interference source model, the study on themagnetic field strength of casing in the pulsed magnetic field with spatial, temporaltendency,provides the basis for the internal design of circuit structure.Then, from the angle of cut off the path of electromagnetic interference, this paperexplores how to improve the protection ability of sensitive device not be affected by the pulse interference effects.Finally, by using the method of finite element simulation, the induction voltage with asame closed loop in different planes in the casing are calculated. By comparing theinduction voltage waveform, the plane position for PCB circuit with minimal interferenceimpact is confirmed.