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The paper describes an electronic multiprocessor system that assures functionality of a miniature UAV capable of 3D flying. The apparatus consists of six independently controlled brushless DC motors, each having a propeller attached to it. Since the brushless motor requires complex algorithms in order to achieve maximum torque, efficiency and response time a DSP must be used. All the motors are then controlled by a main microprocessor which is capable of reading sensors (Inertial Measurement Unit (IMU)-orientation and GPS), receiving input commands (remote controller or trajectory plan) and sending independent commands to each of the six motors. The apparatus contains a total of eight microcontrollers: the main unit, the IMU mathematical processor and one microcontroller for each of the six brushless DC motors. Applications for such an apparatus could include not only military, but also search-and-rescue, geodetics, aerial photography and aerial assistance. [ABSTRACT FROM AUTHOR]

A new brushless variable reluctance machine with stator field winding called Doubly Salient Electromagnetic Generator (DSEG) is described. Configuration and principle of the machine and its rectified circuits are overviewed. The elementary sizing equation of DSEG is analytically developed for the preliminary design. Further design considerations of the key structural parameters e.g. stator back-iron depth, rotor pole width, rotor pole height, air-gap length are systematically studied by 2D-FEA. A 12kW prototype DSEG is developed. The experimental results verify the predicted ones and the presented design constraints. Due to simple construction, non-magnet consumption and controllable output voltage, the DSEG appears to be a desirable candidate for independent dc power generation system. [ABSTRACT FROM PUBLISHER]

This paper estimates the performance of a conventional dc machine that is turned inside-out with the commutator replaced by switch-type semiconductors on the stator. The rotor is a permanent magnet design with trapezoidal radial flux density. Stator windings are full-pole pitch. The torque density for the inside-out dc machine is higher than other types of machines for the same equivalent cooling techniques. A Voltage Source Converter (VSC) method with shaft angle reference is used to coordinate the semiconductor switches. Interaction is shown between the design of the inside-out machine and operation of the ac-dc slot converters. [ABSTRACT FROM PUBLISHER]

A new Brushless Real Time Control (RTC) method for electric motors or generators is an evolution in Sensor-less control. Very different from any derivative of Field Oriented Control (FOC), RTC uniquely eliminates all control uncertainty, including the extraneous shaft connected resolver for the specific purpose of measuring speed-position (i.e., Sensor-less). Although modified versions of RTC can be used for control of any type of electric machine, the variable speed Brushless Wound-rotor [Synchronous] Doubly-fed Electric Machine System (BWRSDF) with its symmetrical circuit topology best explains the attractive attributes of RTC but more importantly, the BWRSDF has been theorized by experts to provide the highest efficiency, highest power density, highest torque density, and lowest cost of any electric machine with practical solutions for known issues of instability and a multiphase slip-ring assembly that only RTC successfully provides. In addition, BWRSDF uses off-the-shelf technology and readily available materials without precious rare earth permanent magnets. [ABSTRACT FROM PUBLISHER]

During the past decade Flux-Switching Permanent Magnet (FSPM) machines have been the object of increasing investigation due to its inherent advantages regarding torque density and fault tolerance. Due to these facts they are greatly attractive for aerospace applications where low-weight and limited installation spaces play an all-important role and where safety is a critical factor. In the search for alternative topologies that comply with these criteria, so that they can be deployed in a More-Electric Aircraft (MEA) for the purposes of propulsion or power generation, recent publications have given attention to a machine variant from the conventional FSPM machine called the C-Core FSPM machine. The C-Core FSPM machine offers roughly 40% greater electromagnetic torque than conventional FSPM machines, while using half of the magnet mass. This paper identifies measures to increase the electromagnetic torque by a further 20% to 30% while maintaining the machine volume and phase current constant and using no more magnet material than a conventional FSPM machine. An approach to exploit this advantage is proposed and developed for use in all FSPM machines. The greatest potential is identified to be in C-Core and E-Core FSPM machines. [ABSTRACT FROM PUBLISHER]