Design of electro-mechanical actuator for medium sized helicopter and a test platform for its testing and verification

This paper presents the design of an electro-mechanical actuator that is used for actuation of a medium sized helicopter. The designed actuator consists of a commercially available electro-mechanical cylinder EMC40 from Rexroth Bosch and a brushless DC motor EC45 from maxon motor. Cylinder and the motor are connected by a custom-made gearbox, which allows for their parallel axial mount. In addition to the actuator, the paper describes a test platform that can be used to emulate the forces generated by an actual helicopter. Designed test platform consists of a torsional spring and an AC motor with excentre. Frequency regulator is used to achieve the desired frequency of the force. Experimental results obtained by testing the designed actuator on the test platform are also given in the paper

Design of electro-mechanical actuator for medium sized helicopter and a test platform for its testing and verification

This paper presents the design of an electro-mechanical actuator that is used for actuation of a medium sized helicopter. The designed actuator consists of a commercially available electro-mechanical cylinder EMC40 from Rexroth Bosch and a brushless DC motor EC45 from maxon motor. Cylinder and the motor are connected by a custom-made gearbox, which allows for their parallel axial mount. In addition to the actuator, the paper describes a test platform that can be used to emulate the forces generated by an actual helicopter. Designed test platform consists of a torsional spring and an AC motor with excentre. Frequency regulator is used to achieve the desired frequency of the force. Experimental results obtained by testing the designed actuator on the test platform are also given in the paper

A Comparative Study of Two Fault-Tolerant Dual-Motor Drive Topologies Under Short-Circuit Inverter Switch Fault

This paper analyzes two dual-motor fault-tolerant topologies for aerospace thruster application. The first structure supplies independently both machines while the second one connects them in series for reducing the number of transistors and offering a capability of energy management between the sources. Inverter short-circuit fault is considered. Based on the peak-currents obtained in simulation in degraded mode without reconfiguration and with two different reconfiguration strategies, the two proposed topologies can be compared in economic and technical aspects

Fault Tolerant Dual-Motor Drives: Sizing of Power Electronic

This paper analyzes two dual-motor fault-tolerant topologies. The first one supplies independently both machines while the second one connects them in series for reducing the number of transistors. For a given DC-link voltage, the converter component sizing is based on the peak current obtained in the normal and degraded modes.CIFFRE - Thales Grou

A high-speed permanent-magnet machine for fault-tolerant drivetrains

This paper details the design considerations of a permanent magnet (PM), three phase, high speed, synchronous machine for fault tolerant operation. A multidisciplinary approach to the optimal design of the machine is adopted targeted at minimising the additional losses resulting from faulty operating conditions and accounting for the remedial control strategy implemented. The design of a closed slot, 6 slots, 4 pole machine is presented. The machine is prototyped and tested to validate the analytical-computational performances predicted in the design and analysis stage under healthy and faulty condition

A Comparative Study of Two Fault-Tolerant Dual-Motor Drive Topologies Under Short-Circuit Inverter Switch Fault

This paper analyzes two dual-motor fault-tolerant topologies for aerospace thruster application. The first structure supplies independently both machines while the second one connects them in series for reducing the number of transistors and offering a capability of energy management between the sources. Inverter short-circuit fault is considered. Based on the peak-currents obtained in simulation in degraded mode without reconfiguration and with two different reconfiguration strategies, the two proposed topologies can be compared in economic and technical aspects

A Comparative Study of Two Fault-Tolerant DualMotor Drive Topologies Under Short-Circuit Inverter Switch Fault

This paper analyzes two dual-motor fault-tolerant topologies for aerospace thruster application. The first structure supplies independently both machines while the second one connects them in series for reducing the number of transistors and offering a capability of energy management between the sources. Inverter short-circuit fault is considered. Based on the peak-currents obtained in simulation in degraded mode without reconfiguration and with two different reconfiguration strategies, the two proposed topologies can be compared in economic and technical aspects.CIFRE - Groupe Thale

Axial Stress Analysis and Comparison of the Novel Dual 3-phase Axial Flux Permanent Magnet Machines

In previous research, a novel three-phase dual-stator axial flux permanent magnet machine characterized by the advantages of compact structure and low moment of inertia is proposed for industrial robot application. In order to improve its functional reliability furtherly, the dual three-phase axial flux permanent magnet machine (DTP-AFPM) is firstly proposed. Benefiting from the combination of 12 slots/10 poles, the coil configuration of one stator disk can be modified to a dual three phase full-pitch winding straightforwardly, as a result, one kind of the DTP-AFPMs is achieved which is named as the no shift model in this paper. For eliminating the coil reconfiguration on each stator disk and the connection of the coils belonging to the same phase between two stator disks, the shift model which is based on the shift of the two stator disks to obtain the phasor difference between two three-phase windings is introduced. The characteristics and electromagnetic performances of these two models are analyzed and compared. However, it should be noted that the light-weight disk-type rotor of DTP-AFPMs also degrade the strength of the rotor. The proposed DTP-AFPMs are more sensitive to the axial stress on the rotor which introduces not only the vibration and noise but also the deformation or even the damage of the rotor. Thus, the axial stress on the rotor is investigated and treated as a critical evaluation indicator. The axial stress is analyzed under both healthy and fault conditions and its distribution on the rotor is given on a 2-D plane

Induction motors versus permanent magnet actuators for aerospace applications

This paper introduces a comparative study on the design of aerospace actuators concerning Induction Motor (IM) and Permanent Magnet Motor (PMM) technologies. In the analysis undertaken, the two candidate configurations are evaluated in terms of both their electromagnetic and thermal behavior in a combined manner. On a first step, the basic dimensioning of the actuators and their fundamental operational characteristics are determined via a time-stepping Finite Element (FE) analysis. The consideration of the thermal robustness of the proposed motor configurations is integrated in the design procedure, through the appropriate handling of their respective constraints. As a result, all comparisons are carried out on a common thermal evacuation basis. On a second step, a single objective optimization procedure is employed, considering several performance and efficiency indexes using appropriate weights. Manufacturing and construction related costs for both investigated topologies are considered employing specific penalty functions. The impact of the utilized materials is also examined. The resultant motor designs have been validated through manufactured prototypes illustrating their suitability for aerospace actuatio

Modular Permanent Magnet Machines with Alternate Teeth Having Tooth Tips

This paper presents single layer modular permanent magnet machines with either wound or unwound teeth with tooth tips. The structures with wound teeth having tooth tips are suitable for modular machines with slot number higher than pole number to compensate for the drop in winding factor due to the flux gaps in alternate stator teeth, accordingly to maintain or even to increase their average torques. However, the structures with unwound teeth having tooth tips are suitable for modular machines with slot number lower than pole number to increase the winding factor and hence to further improve the machine performance. The phase back-EMF, on-load torque, iron and copper losses as well as efficiency have been calculated using finite element analysis for different slot/pole number combinations, and for different flux gap and tooth tip widths. It is found that by properly choosing the flux gap and tooth tip widths, both the on-load torque performance and the efficiency can be optimized for the investigated machines with different slot/pole number combinations. Experiments have been carried out to validate the finite element results