Parallel SiC MOSFETs Marx Pulse Generator Based on Magnetic Induction Current Balance

In order to meet the demands of fast rise times, short pulsewidth, and high repetition frequency and enhance the output current level of the Marx pulse generator for high-power pulse applications, this article proposes a pulse generating technique based on parallel SiC MOSFETs. The magnetic induction current balance (MICB) method is employed to effectively address the issue of current imbalance by utilizing a coupling coil, enabling Marx pulse generator to achieve larger pulse current output. The mechanism of generating and suppressing transient as well as static unbalanced currents is analyzed by establishing mathematical model. The ability of magnetic induction coupling coil to suppress static imbalance current during the pulse plateau is accurately evaluated to ensure great current equalization effect for different pulse widths. Circuit simulations verify theoretical correctness and effectiveness. The magnetic induction coupling coils are designed and optimized based on theory and simulation, enhancing the generator compactness. Additionally, an eight-stages Marx prototype is built, and performance tests are conducted. The results demonstrate that, under the conditions of the pulse source output voltage of 5 kV, output current of 50 A, maximum repetition frequency of 10 kHz, and pulse widths ranging from 50 to 1000 ns, the magnetic induction coupling coils effectively suppress the transient and static imbalance currents in the parallel SiC MOSFETs. This ensured the reliability and stability for the larger current output of the pulse generator. Higher voltage and larger current outputs can be achieved by increasing the number of Marx modules and parallel switching devices.