C. Whitley

The results do mesh

This article considers the effects of open-circuited phase windings and of shorted coil turns of the stator winding on the operation of the induction machine. The analysis and comparison of faulted modes of operation is achieved by simulation, using the dynamic mesh reluctance model (DMRM) approach. The DMRM approach gives valuable insight of induction motor detection of the faulted windings. Clearly, five-phase motors with third harmonic control give the best performance for machines with one-phase open circuit, and careful machine design can minimize adverse effects of torque ripple

A comparison of the reliability of a matrix converter and a controlled rectifier-inverter

This paper compares the calculated reliability of a matrix converter with a controlled rectifier/inverter topology for an aerospace motor drive application. These topologies are functionally equivalent in terms of input power quality and regenerative capabilities. The military handbook MIL-HDBK-217F guidelines have been used to predict reliability. Although the matrix converter has a higher number of semiconductor switches, these switches are subjected to a lower voltage stress, which can shown to increase the device reliability. When this factor is taken into account it can be shown that the predicted reliability of the matrix converter is actually slightly better than the controlled rectifier-inverter solution

A matrix converter based permanent magnet motor drive for an aircraft actuation system

This paper describes the design, construction and testing of a matrix converter permanent magnet motor drive for an electro-hydrostatic aircraft actuator (ERA). The converter has been built using a 35Amp Eupec matrix converter module with closed loop vector control. The commutation time has been minimized to avoid any unnecessary waveform distortion. Practical results from the testing of this converter are presented.

High Torque Density PM Machines for High Performance Operation

This paper looks at different construction methods and coil winding techniques for fractional slot, high torque density permanent magnet synchronous machines intended for high performance aerospace applications. Whilst mechanical gearing is often used to reduce the size and mass of an electromechanical system by operating the machine at high speeds this paper shows that by utilizing machine topologies with low number of slots per pole a better power density can be achieved without any mechanical gearing.

Power supply loss ride-through and device voltage drop compensation in a matrix converter permanent magnet motor drive for an aircraft actuator

In any aerospace application it is important that the size and weight of power converters are minimized. This requirement, in conjunction with the absence of the requirement for electrolytic capacitors, suggests that matrix converters could be a very useful topology for aerospace applications. In order to investigate the possible advantages and problems associated with the use of matrix converters in this type of application a permanent magnet motor drive for a demonstration A320 electro-hydrostatic (EHA) Aileron actuation system has been built and tested. The Aileron is a primary flight surface due to it being critical to flight stability. Actuation of this type must exhibit the highest integrity to ensure safe operation of the aircraft. The matrix converter has been designed to function correctly under a range of operating scenarios found in many aerospace applications, including ride-through during temporary loss of supply. This paper presents the design, construction and testing of this matrix converter permanent magnet motor drive, including practical results for a range of operating conditions.

A 5-Phase Fault-Tolerant Brushless Permanent Magnet Motor Drive for an Aircraft Thin Wing Surface Actuator

This paper describes work on an integrated Electro Hydrostatic Actuator (EHA) intended as a technology demonstrator to satisfy future aircraft requirements for smaller profile wing surfaces. The design and analysis of an integrated actuator package, comprising a high speed, 5-phase, brushless permanent magnet (PM) machine driving a variable displacement hydraulic pump is considered. The main goals of the design are a high level of actuator integration in order to minimize weight and volume, fault tolerance and high reliability. The constraints imposed by the operating environment, the converter supply and the hydraulic fluid on the machine deign will be addressed.

The impact of matrix converter technology on motor design for an integrated flight control surface actuation system

This paper describes research related to producing integrated electric motor driven flight control surface actuation systems, for a More Electric Aircraft. The main requirements and motor options are discussed. The advantage of the matrix converter in terms of compactness, due to removal of energy storage elements, is highlighted. However, this advantage is shown to bring with it problems when motors which have pulsed voltage and current waveforms are employed. The resulting discontinuities in power flow during current commutations are reflected at the input terminals to the drive as supply current harmonics.

Fault- Tolerance Analysis of Multi-Phase Single Sided Matrix Converter for Brushless DC Drives

This paper introduces the single sided matrix converter (SSMC) as a reliable power electronic drive for brushless dc motors used in aerospace applications. The multi-phase SSMC provides high reliability and fault tolerance with the penalty of more power devices. Dynamic Matlab simulations using a full model of the converter, machine and switching control algorithm are performed to investigate the fault tolerance of the multi-phase topologies.

Integrated Machine design for Electro Mechanical Actuation

This paper describes work on an integrated electro mechanical actuator intended as a technology demonstrator to satisfy future aircraft requirements for a typical mid spoiler actuation system for a large civil aircraft. The design and analysis of a directly coupled motor to a roller screw without any intermediate gear box will be detailed in this paper. The main goals of the design are a high level of actuator integration in order to minimize weight and volume, fault tolerance and high reliability.

A matrix converter based permanent magnet motor drive for an electro-hydrostatic aircraft actuator

This paper describes the design, construction and testing of a matrix converter permanent magnet motor drive for an electro-hydrostatic aircraft actuator (EHA). The converter has been built using a 35Amp Eupec Matrix Converter module with closed loop vector control. The commutation time has been minimized to avoid any unnecessary waveform distortion. Practical results from the testing of this converter are presented.