Circuit Simulations of Plasma Discharges in CMFX

The Centrifugal Mirror Fusion Experiment (CMFX) aims to harness the potential of azimuthal rotation to enhance plasma confinement within a magnetic mirror. The rotation is imposed by applying a high voltage from a capacitor bank to a central electrode, creating a radial electric field that helps stabilize and heat the plasma. Understanding the interactions between the plasma, the capacitor bank, and other external circuit elements is challenging. This work simulates the plasma as a capacitor in parallel with a resistor. However, the values of these elements were not immediately known. The entire electrical circuit was entered into the LTSpice simulation software to find these values. The parameter values were varied systematically until the simulated plasma current and voltage, measured in the experiment, were qualitatively and quantitatively similar. The results are being compared with theoretical predictions of plasma capacitance and resistance. They are an important tool for the design of a scaled centrifugal mirror as a fusion energy reactor. Details of the circuit, simulations, and methodology are presented.