Dynamics of magnetic pulse compression circuit of metal vapor laser

Abstract

Solid-state pulse power supply uses magnetic pulse compression circuit (MPC) to reduce the rise time of the voltage pulse applied across the Metal vapor Laser (MVL). In MPC, the nonlinear characteristics of ferromagnetic material is leveraged, to obtain large change in its inductance. These inductors get saturated during application of desired voltages and offer low impedance, which acts like a closed switch. It is desirable to fix the operating point in the B-H curve for smooth functioning of the switch, hence a current is applied to the magnetic switch to reposition the operating point on B-H curve from positive saturation flux to negative before appearance of next pulse. In MVL proper reset becomes extremely important because of small tolerance in the timing, for obtaining low jitter requirement.At low repetition rate, resetting of magnetic switch is easy as the oscillation in L-C circuit in MPC dies out before the next pulse. However, as the repetition rate increases there is very little time for reset dynamics to take place before the next pulse. In this paper we are presenting detailed dynamics of 9 kHz pulse repetition rate MPC for MVL. B-H curve have been derived using voltage, current waveform and Jiles Atherton equation in simulation model. We have shown how MPC oscillation affects the B-H curve of the magnetic switch. An experimentally validated simulation model is developed for detailed analysis of dynamics of MPC and to observe other implications like effect of reset on jitter in output of MPC.