Abstract:

A long pulse width solid-state Linear Transformer Driver (LTD) is designed by means of pulse superposition for high voltage, large current and wide range pulses required in biomedical applications of pulsed electromagnetic fields. To break through the pulse width range under the volt-second product limit of the pulse transformer, the LTD increases the output pulse width using parallel superposition. The reset circuit of the pulse transformer is designed to improve the output pulse duty cycle of LTD, so that the multi-pulse superposition of the minimum branch LTD can be achieved. A simulation circuit model is built on Pspice to verify the design principle and the effect. In the case of a single-turn pulse transformer with a volt-second product of 146 V · ms, a pulse output with a single-stage voltage of 300 V and a pulse width of 1.6 ms is realized, which is 3 times of its original volt-second product, and a wider range of pulse extension can be achieved by increasing the number of superimposed pulses.

Key words: pulse power technology, linear transformer driver, pulse power supply, pulse width extension, pulse superimposed, microsecond pulse, pulse transformer, saturation magnetization