Circuit modeling of rotating magnetic field field-reversed configuration thrusters
A lumped circuit model is presented for the formation and propagation of a rotating magnetic field field-reversed configuration thruster. The driving coils are treated as two lumped circuit inductors operated 90◦ out of phase. The plasma is modeled as an inductive load with capacitive and resistive elements, and a series of equations are derived based on Kirchhoff’s laws and charge continuity. Plasmoid translation is captured by modeling the whole plasma as a conducting slug undergoing acceleration due to the Lorentz force. Two operating regimes are analyzed: the system with coupling to the plasma and the case in which the ring down of the coils during discharge is fixed. It is found that for high input energies, the efficiency scales inversely with input energy. In addition, several notable trends can be observed in the numerical data. Both specific impulse and efficiency increase with coupling. There is also indication of an optimum efficiency as input energy changes. These observed trends are discussed in the context of projected thruster performance.
