The Precharge Time Increasing Circuit of RSD Without Upgrading the Magnetic Switch

Reversely switched dynistor is a two-terminal semiconductor switch with high critical current rising rate and peak current, and is triggered by the reverse pre-charge current. To generate the reverse current, a magnetic switch is used to block the main capacitor discharge during pre-charge. The complex trigger circuit with the magnetic switch serves as the most important factor to limit the widespread application of RSD in high-voltage occasions. Typically, to keep the blocking time (saturation time) within proper range for triggering RSD at high voltages, the size or the winding turns of the magnetic switch needs to be increased to increase the voltage-time product, leading to higher weight and saturated inductance. In this study, the pre-charge time increasing circuit of RSD without changing the voltage and without increasing the size or winding turns of the magnetic switch is proposed. By adding an auxiliary winding, the pre-charge time and the equivalent voltage-time product of a magnetic switch have been increased by up to 20.8%. This study decreases the size and saturated inductance of magnetic switch at high voltages and is favorable for the application of RSD in pulsed power field.