Lamination stack for stator Fitting windings into stator Completed stator windings Rotor with fitted windings
The making of E-Kite’s 80 kW direct drive generator
E-Kite’s 80 kW ground station (13 May 2016)
Hisham Eldeeb PhD Researcher Technical University of Munich
Munich School of Engineering Control of Renewable Energy Systems
Lichtenbergstraße 4a 85748 Garching
Germany
hisham.eldeeb@tum.de www.cres.mse.tum.de
CRES
Control of renewable energy systemsHighly Efficient Fault-Tolerant Electrical Drives for Airborne Wind Energy Systems
Hisham Eldeeb1, Ayman S. Abdel-Khalik2, Christoph M. Hackl1
1Technical University of Munich 2Texas A&M University, Doha
Airborne wind energy systems are considered to be a highly efficient cost-effective replacement for conven-tional wind turbines (CWTs). However, several correlated design and engineering aspects hinder the commercial-ization of such technology. The selection of a highly ef-ficient fault-tolerant electrical drive is still challenging especially for those AWE concepts based on reel-in/out for power generation. Employing the same topology of three-phase electrical drives as those for CWTs is disad-vantageous due to two reasons.
1. Failure rates of the electrical components of CWT in several studies indicated that power converters are highly likely to fail [1], [2]. Upon isolation of the faulty part, the machine behaves as a single phase machine, which is non-self-starting, incapable of reversing rota-tion direcrota-tion and derates to ≈ 33% of the pre-fault condition to avoid substantial overheating.
2. Fault-tolerance using a backup machine and/or con-verter is of limited fault-tolerance capability and is cost-ineffective.
A suitable alternative is to split each phase into two inde-pendent phases, which is also known as dual three-phase machines (DTMs). In case of a fault, one of the DTM con-figurations can reach up to ≈ 80% of the pre-fault torque [2]. Additionally, subsidiary achievements such as higher efficiency, 50% reduction in converter ratings [1], signifi-cant reduction in DC-link voltage requirement, and lower torque ripples (which translates into less audible noise)
are granted for the same machine and hardware configu-ration.
The shown figure represents the practical test-bench containing interior permanent magnet synchronous ma-chine (IPMSM), which has been rewinded as a DTM. It is currently undergoing several experiments, which aim at enhancing the drive performance during pre- and post-fault operation.
I
III
II
Practical setup containing: I- IPMSM-DTM, II- load machine resem-bling the Kite, and III- torque sensor.
References:
[1] I. G.-Prieto, M. J. Duran, H. S. Che, E. Levi, M. Bermudez, and F. Barrero, łFault-tolerant operation of six-phase energy conver-sion systems with parallel machine-side converters,ž IEEE Trans. on Power Electron., vol. 31, pp. 3068ś3079 (2016)
[2] W. N. W. A. Munim, M. Duran, H. S. Che, M. Bermudez, I. G.-Prieto, and N. A. Rahim, łA unified analysis of the fault tolerance capabil-ity in six-phase induction motor drive,ž IEEE Trans. on Power Elec-tron., no. 99, pp. 1ś1 (2016).
