The “E‑FFEKT” project, carried out at the Institute for Electrical Engineering of the TU Bergakademie Freiberg under the leadership of Stanislav Henkel, ran from 1 January 2015 to 30 June 2018 and was funded under the German Ministry of Education and Research with the grant code 01MY14007A. Its central aim was to develop an energy‑ and cost‑efficient alternative to permanent‑magnet synchronous machines (PSM) by optimizing rotor‑flux control in asynchronous machines (ASM). The project was organised into eight work packages, covering analytical design, 2‑D finite‑element modelling in OPERA, numerical optimisation, procurement of a 50 kW ASM, implementation of the rotor‑flux controller on a drive system, and experimental validation on a 200 kVA dynamic test rig equipped with a vehicle‑energy system.

The technical outcome of the project is a 50 kW, 180 V, 100 Hz, 30 000 rpm ASM that was analytically designed, numerically optimised, and fabricated. The machine’s physical dimensions are 205 mm in length, 150 mm in diameter, with a 236.8 mm outer diameter and 90 mm inner diameter, and it weighs 58.124 kg (10.726 kg copper, 25 kg iron, 10.567 kg iron core, 22.556 kg iron stator, 7.289 kg iron rotor, 0.327 kg iron ring). Electrical parameters include a stator resistance of 5.559 Ω, rotor resistance of 0.246 Ω, and a stator‑to‑rotor impedance of 1.16 Ω. The machine delivers 51 kW of mechanical power and 162.4 Nm of torque at a slip of 1.16 % and a power factor of 0.905. The rotor‑flux controller, designed to optimise efficiency by accounting for secondary effects, achieved an efficiency exceeding 85 % across the operating range, matching the performance of PSMs while avoiding the high cost of rare‑earth magnets.

Simulation results showed that the new rotor‑flux control strategy outperformed conventional cos φ control, particularly at higher stator frequencies where efficiency losses are normally pronounced. The controller was integrated into the drive system and evaluated on the demonstrator; however, delays in external motor procurement and challenges in implementing the control on the purchased power‑electronics board prevented the completion of milestone 3 within the project timeframe. Despite these setbacks, the project demonstrated the feasibility of a serially viable ASM with performance comparable to that of a PSM, offering a cheaper alternative for electric‑vehicle propulsion.

Collaboration within the project remained internal to the Institute for Electrical Engineering; an intended industry advisory board was not established. The project’s deliverables were confined to the institute’s research activities, and no external partners were involved. The funding, provided by the German federal research programme, supported the entire research effort, including design, simulation, manufacturing, and testing. The project’s outcomes, including the detailed machine data and the developed rotor‑flux control algorithm, are intended for further dissemination and potential industrial uptake, aligning with the planned exploitation strategy of the funding programme.