Design, analysis and test of the dual three-phase permanent magnet vernier superconducting armature electrical machine prototype

Abstract Offshore wind power generation has broad application prospects. The current single-unit capacity of offshore wind generators exceeds 20 MW. Superconducting (SC) armature permanent magnet (PM) generators have high current-carrying characteristics and can overcome the bottlenecks of the copper armature PM synchronous generator in terms of volume and weight. However, existing SC armature windings usually use an integrated Dewar, which is difficult and costly to design and is not conducive to maintenance. In addition, SC armature windings are mostly three-phase windings, and the fault-tolerant operational capability of SC armature electrical machines is poor. In response to the above problems, this paper proposes a dual three-phase PM vernier SC armature electrical machine (DTVSM), which adopts an SC magnet with a static seal of the cooling medium. Each SC magnet used a modular Dewar and contained two sets of SC coils. The SC magnets are connected externally to form a dual three-phase SC armature winding, which improves the fault-tolerant operational capability of the SC armature PM electrical machine. Compared with the 20 MW copper armature PM synchronous electrical machine, the unit volume torque density of the proposed DTVSM is about 108.22 kN·m m −3 , which represents an improvement of about 60%, indicating significant application potential. This study designs and tests a 10 kW prototype, focusing on the electrical machine topology, working principle, and manufacture of SC magnets and prototype, and the related experimental tests verify the feasibility of the DTVSM technology route.