Abstract: A flux pump having a closed superconducting circuit including wire of relatively high critical field and a gate defining a current-carrying path through a coil, the latter being moveable relative to a magnetic field source to cause normal conduction of current in a plurality of gate modules of a relatively low critical field in the circuit at spaced locations along the same. Thus, a flux pumping action occurs in the coil as the modules are subjected to the field of the source. The modules are separated from each other by strips of insulation material and the wire, connected to opposite ends of the gates, passes through adjacent insulation strips in a manner such that the current flow in the circuit is always in the same direction. The speed of the flux pumping action can be increased by having several groups of modules arranged in parallel with each other and excited simultaneously with a number of modules in each group being in series with each other.