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Electrical machines for aircraft applications require basic characteristics such as lightweight, high reliability, fault tolerance ability, and torque power and higher densities. Correspondingly, hybrid excitation flux switching machines (HE‐FSMs) are capable of producing significant characteristics of high torque and power by improving flux strengthening in the iron core. However, magnetic flux cancellation and leakage in HE‐FSMs cause the reduction of flux linkage created by permanent magnet (PM) and field excitation (FE), which leads to deterioration of electromagnetic torque. This study presents magnetic flux performance and comparison of various topologies of HE‐FSMs by employing different positions of PMs and FE coils on the stator core. The purpose of a segmented rotor is to deliver a well‐defined electromagnetic flux pathway for carrying magnetic flux to nearby armature coil on stator with rotor rotation to improve the flux strengthening. Moreover, magnetic performances of various proposed HE‐FSMs at different positions of PMs are investigated and compared based on 2D finite element analysis. Subsequently, the enhanced HE‐FSM III has successfully achieved flux strengthening of 22%, torque of 54% and power of 61% more than initial design of HE FSM I, respectively. In conclusion, the proposed HE‐FSM structures show the capability to match high torque and power for aircraft applications.

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Design parameter sensitivity study and performance analysis of 12Slot-8Pole wound field salient rotor (WFSalR) switched-flux machine (SFM) for hybrid electric vehicle (HEV) applications is presented in this paper. The proposed WFSalR SFM consists of 6 armature slots, 6 field excitation coil (FEC) slots and 8 rotor poles. The main advantage of these SFMs when compared with induction machines, synchronous machines, direct current (DC) machines etc is that all the active parts such that armature coil and FEC coil are located on the stator while the rotor part consists of only single piece iron. This makes the machine more robust, simple structure and more suitable to be used for high speed HEV applications. Non-overlap armature and field windings at the stator reduces the copper consumption and also the copper losses. First of all, the initial performance, the main structure and analysis based on two-dimensional Finite Element Analysis under certain limitations and specifications are discussed. Since the initial design fail to attain the maximum torque and power, therefore the performance of machine is enhanced by refinement of several design parameters defined in rotor, FEC and armature slot area. After design refinement, WFSalR FSM has achieved the maximum torque of 22.34 Nm and power of 5.27 kW at maximum field current density, J e of 30 A/mm 2 and armature current density, J a of 30A rms /mm 2 which is approximately 3 times the torque and 2 times the power of initial design.

Attitude Control System (ACS) is one of the critical subsystems of any spacecraft andtypically is in charge of de-tumbling, controlling and orienting the satellite after initial deployment and during the satellite operations. The magnetorquer is a core magnetic attitude control actuator and, therefore, a good choice for nanosatellite attitude stabilization. There are various methods to achieve control torque using the magnetorquer. An innovative design of printed magnetorquer has been proposed for the nanosatellites which is modular, scalable, cost effective, less prone to failure, with reduced harness and power consumption since the traces are printed either on top layer or inner layers of the printed circuit board. The analysis in terms of generated torque with a range of input applied voltages, trace widths, outer and inner-most trace lengths is presented to achieve the optimized design.The optimum operating voltage is selected to generate the desired torque while optimizing the torque to the power ratio. The results of analysis in terms of selection of optimized parameters including torque to power ratio, generated magnetic dipole moment and power consumption have been validated practically on a cubesat panel. The printed magnetorquer configuration is modular which is useful to achieve mission level stabilization requirements. For spin stabilized satellites, the rotation time analysis has been performed using the printed magnetorquer.

The main objective of aerospace industry is to produce all electric aircraft (AEA) equipped by electrical devices in coming developments. Electrical machines that provide higher torque densities are gaining more interest for researchers to obtain sustainable direct-drive electrical propulsion system for aircraft applications. In addition to lesser weight and higher torque density, a machine should be “fault tolerant” to applied in aerospace applications. A novel machine for high starting torque, identified as flux switching machine (FSM) was established over the last decade. FSMs comprise all effective sources on stator including robust rotor structure. These machines exhibited higher “torque-to-weight ratios” and reliability. Nonetheless, the challenge of developing a machine suitable for aircraft applications goes far beyond electromagnetic design and much deeper into the field of mechanical systems than traditional ones. Thus, a new double stator (DS) hybrid excitation (HE) FSM design employing segmented rotor is proposed and analyzed in this research work. The suggested design for DS HE-FSM comprises of six field excitation coils (FECs) and six permanent magnets (PMs) as their excitation sources. In this research, investigation of DS HE-FSM is accomplished with respect to flux linkage, back EMF, cogging torque and torque analysis based on 2D FEA.

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