A system for generating a magnetized plasma and sustaining a magnetic field of the magnetized plasma, the system comprising: a plasma generator for generating the magnetized plasma and comprising an outer electrode and an upper central conductor located coaxially within and spaced from the outer electrode to form an annular plasma propagation channel with an outlet, a fuel injector for injecting a plasma fuel into an upstream end of the annular plasma propagation channel; one or more coils operable to generate a magnetic field in the annular plasma propagation channel which provides a poloidal field for the magnetized plasma; a flux conserver having an outer wall and a lower central conductor located coaxially within and spaced from the outer wall to define an evacuated inner cavity with an entrance in fluid communication with the outlet of the annular plasma propagation channel and through which the magnetized plasma is injected into the inner cavity, wherein one end of the lower central conductor is electrically coupled to one end of the upper central conductor and another end of the lower central conductor is electrically connected to the outer wall of the flux conserver; and a power supply source electrically coupled to the upper and lower central conductors (21a, 21b) such that a current flows along the upper and lower central conductors (21a, 21b) and the outer wall of the flux conserver, the power supply source comprising a formation power circuit configured to generate a formation power pulse sufficient to flow current radially across the plasma fuel between the upper central conductor and the outer electrode to generate the magnetized plasma from the plasma fuel in the plasma generator and to inject the magnetized plasma into the flux conserver, and a sustainment power circuit configured to generate a sustainment current pulse along the upper and lower central conductors (21a, 21b) and the outer wall of the flux conserver sufficient to generate a toroidal magnetic field in the plasma generator and the flux conserver. a plasma generator for generating the magnetized plasma and comprising an outer electrode and an upper central conductor located coaxially within and spaced from the outer electrode to form an annular plasma propagation channel with an outlet, a fuel injector for injecting a plasma fuel into an upstream end of the annular plasma propagation channel; one or more coils operable to generate a magnetic field in the annular plasma propagation channel which provides a poloidal field for the magnetized plasma; a flux conserver having an outer wall and a lower central conductor located coaxially within and spaced from the outer wall to define an evacuated inner cavity with an entrance in fluid communication with the outlet of the annular plasma propagation channel and through which the magnetized plasma is injected into the inner cavity, wherein one end of the lower central conductor is electrically coupled to one end of the upper central conductor and another end of the lower central conductor is electrically connected to the outer wall of the flux conserver; and a power supply source electrically coupled to the upper and lower central conductors (21a, 21b) such that a current flows along the upper and lower central conductors (21a, 21b) and the outer wall of the flux conserver, the power supply source comprising a formation power circuit configured to generate a formation power pulse sufficient to flow current radially across the plasma fuel between the upper central conductor and the outer electrode to generate the magnetized plasma from the plasma fuel in the plasma generator and to inject the magnetized plasma into the flux conserver, and a sustainment power circuit configured to generate a sustainment current pulse along the upper and lower central conductors (21a, 21b) and the outer wall of the flux conserver sufficient to generate a toroidal magnetic field in the plasma generator and the flux conserver.