Model analysis and simulation of a self-trigger LTD module

Owing to the significant advantages of linear transformer driver (LTD) technology, it becomes a new pulsed power technology for the construct of high-voltage, high-current pulsed-power accelerators. However, the LTD technology requires that the closure of the switches in the cavities are synchronized with the arrival of the electromagnetic pulse propagating downstream and the trigger technology is hard to achieve the stringent demands on the cavity-triggering sequences at present. In this paper, one kind of self-trigger LTD technology which is based on the principle of electromagnetic induction is proposed. In order to explore the feasibility of self-trigger LTD, a circuit model of a self-trigger LTD module composed of 60 1-MA cavities is established in PSPICE. Through simulation of the model, in which the closure of the gas switches in the cavities are depended on the threshold voltages of gas switches, the output pulse shaping capability of a self-trigger LTD module is analyzed. The results demonstrate that the 10%-90% rise time and the peak of output current of the self-trigger LTD module is acceptable compared with the output current of a LTD module, in which the firing sequence of each LTD cavity is synchronized with the speed the electromagnetic pulse propagates along the output line. The self-trigger LTD module can generate synchronous trigger pulses with the 10%-90% rise time of 53ns and the peak voltage of 100kv. The self-trigger LTD modules with different cavity-triggering sequences are simulated and their cavity-triggering sequences have been detected. The peak current at the output of self-trigger LTD module is in the range of 0.91MA to 0.95 MA with the 10%-90% rise time alters in the range of 53ns to 70n.