Development Of Pulse Magnetic Field Generator Based On Magnetic Field Focusing Technology And Solid Switch

In order to study the biological electromagnetic effect of pulse magnetic fieldapplied in cancer treatment and explore the parameter setting which can treat tumoreffectively. A pulse magnetic field generator is developed based on pulsed powertechnology, magnetic field focusing technology and solid switch.This paper initially establishes the geometric model of coil array and selects theright coil parameter such as sub-coil radius and wire diameter after simulation usingComsol Multiphysics software. Then the magnetic field focusing ability is measuredand evaluated after completing the machining of coil array. The results show that thecoil array has a good focusing ability that can gather the magnetic field to a small area.After the development of focusing coil array, we use genetic Algorithms tooptimize its focusing performance and obtain the current combination in order to getbest focusing ability. After that, we compared the focusing effect of optimization andbefore optimization. The results show that the focusing performance has improved afteroptimization; it has a guiding significance for the development of generator.Finally, the pulse magnetic field generator based on solid switch has beendeveloped. IGBT module and IGBT single tube are used in the generator respectively.After the selection of IGBT, driving circuit and designing of controlling circuit,driving-protecting circuit, the generator is developed and tested. The testing resultsshow that the pulse current amplitude is up to1000A, rising time is3μs, pulse width is5.5μs, and amplitude of magnetic induction is14.4Gs when the capacitor is2μF forIGBT module circuit. Similarly, pulse current amplitude1500A, rising time3μs, pulsewidth5.5μs, amplitude of magnetic induction18.9Gs for capacitor of10μF. As forIGBT single tube parallel generator, the output pulse current amplitude is1000A, risingtime is1μs, pulse width is3.5μs, and amplitude of magnetic induction is10Gs. Theoutput parameter of pulse magnetic field generator meets the design requirements,which can applied to medical experiments.