An LTspice Electrical Circuit Model of the HTS Dynamo

The high-temperature superconducting (HTS) dynamo enables injection of large DC currents into a superconducting coil, without the need for bulky and thermally-inefficient current leads. For practical applications of such technology - like energizing superconducting coils in superconducting rotating machines and NMR/MRI magnets - modelling and understanding the behavior while charging a coil is of great interest. From an electrical circuit point of view, the HTS dynamo can be modelled as a current-controlled voltage source with a specified transresistance corresponding to the effective (internal) resistance. The overall charging curves of a coil by an HTS dynamo can be accurately (and quickly, in seconds or less) predicted using such an electrical circuit model by connecting an RL load representing a coil and any circuit resistance. In this work, an electrical circuit model of the HTS dynamo built in the circuit simulation software LTspice is described. The model is then used to simulate the charge of an HTS coil under different practical scenarios, and the results validated against both numerical and experimental results published in the literature.