Abstract
Fully superconducting machines provide the high power density required for future electric aircraft propulsion. However, superconducting windings generate AC losses in AC electrical machine environments. These AC losses are difficult to eliminate at low temperatures, and they add an extra burden to the aircraft cooling system. Due to the heavy cooling penalty, AC loss in the HTS stator is one of the key topics in HTS machine design. In order to evaluate the AC loss of superconducting stator windings in a rotational machine environment, we designed and built a novel axial-flux high temperature superconducting (HTS) machine platform. The AC loss measurement is based on the calorimetric boiling-off of liquid nitrogen. Both total AC loss and magnetisation loss in the HTS stator are measured under the condition of a rotational magnetic field. This platform represents a key element in studying ways to minimise AC losses in an HTS stator, in order to maximise the efficiency of fully HTS machines.
Highlights
The power density of current electrical machines is not high enough for advanced propulsion applications in all electric aircraft [1,2,3,4,5,6,7,8,9,10,11,12]
Qtotal refers to the total heat produced in the chamber, QHTS refers to the heat caused by the High temperature superconductors (HTS) coil AC loss, Qbackground refers to the unavoidable heat leakage in the system, Qrotation refers to the thermal balance condition change when liquid nitrogen was stirring by the rotor and the Joule heat produced by other stator coils, Qterminal refers to the Joule heat cause by copper terminal and solder joint resistance between HTS and copper current leads
Conclusion and future work The measurement for total AC losses in Figure 13 was performed in a generator mode, so the transport current and the rotational magnetic field are in phase
Summary
The power density of current electrical machines is not high enough for advanced propulsion applications in all electric aircraft [1,2,3,4,5,6,7,8,9,10,11,12]. Qtotal refers to the total heat produced in the chamber, QHTS refers to the heat caused by the HTS coil AC loss, Qbackground refers to the unavoidable heat leakage in the system, Qrotation refers to the thermal balance condition change when liquid nitrogen was stirring by the rotor and the Joule heat produced by other stator coils, Qterminal refers to the Joule heat cause by copper terminal and solder joint resistance between HTS and copper current leads. These losses in Equation 2 can be quantified by a set of calibration procedures. 0.3 W, this value is making sense in platform based on calorimetric method
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
