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This paper introduces several new concepts for improving the peak electrical power capability of an aircraft. This capability is becoming very important for the development of future electric power systems and is reflected in the Honeywell more electric architecture (MEA) design concept and energy optimized aircraft (EOA) initiative. There are many system benefits of using electrically driven actuators on aircraft rather than those that are hydraulically driven. These benefits include enhanced reliability, lower weight, lower volume, and lower cost. However, the introduction of electromechanical actuation (EMA) and electro-hydrostatic actuation (EHA) into aircraft systems has increased the needs for peak electrical power demand.

This paper presents new concepts for improving management of the electrical load power regeneration of an aircraft. A novel electrical system that allows for load regeneration back to the distribution bus is described. This approach offers the benefits of reduced weight, volume, and cost, as well as improved reliability. Also described is an electrical machine control mechanism that creates motor power to run the prime mover (i.e., the main engine to dissipate the regenerated power). Instead of main engine generation, this approach can be applied to an auxiliary power unit (APU) or power and thermal management system (PTMS). Background information regarding the regeneration concept is presented. The concept definition and the various modes of operation of the improved system are analyzed and described in detail. Results from the dynamic simulation of the system model are included.

This paper presents a novel sensorless control topology called floating frame controller (FFC) for driving synchronous electrical machines using an inverter. Position sensorless control of electrical machines used in aerospace applications is increasingly becoming important due to many system advantages including reducing cost and weight, increasing reliability, and the capability of working in harsh environments. A conventional synchronous machine typically uses rotor position sensors to provide information regarding the position of the machine's rotor with respect to the machine's stator windings. Rotor position sensors such as Hall Effect devices are typically mounted on the stator in close proximity of the stator windings. The rotor position sensors provide rotor position information, which allows for proper control for the conversion of power that is supplied to the stator windings of an electrical machine [1].

This paper presents a novel scheme for the start-up of prime movers in starter/generator systems, such as main engine and auxiliary power units (APUs) in aerospace applications. The paper discusses this novel technique in detail for providing single-phase excitation techniques to a start exciter in a starter/generator system to increase the torque per ampere and lower the excitation voltage requirement. Simulation results are provided comparing this novel scheme with a traditional method.

This paper focuses on advances in active power converter topologies for power quality solutions for More Electric Aircraft (MEA). Advancements in power electronics encompass many technologies including power semiconductors, microprocessors or digital signal processors (DSPs), and component packaging. Hence, active power electronic solutions are becoming more attractive from the perspective of weight, volume, performance and cost. A particular contribution that leads to these advancements is the feasibility of implementing the robust control topologies using faster processors. In this paper various active topologies are reviewed, but a particular emphasis is given to a novel control topology for an active filtering technique where an overall reduction of current harmonics of an aircraft power distribution system can be achieved at the system level rather than at the Line Replaceable Unit (LRU) level.

In this paper, various active and passive configurations for a rectification system that minimize the characteristic harmonics of the input phase current waveform and achieve compliance with the harmonic current specifications for future more electric aircraft will be presented. The passive topologies involve multi-pulse transformer rectification systems while the active topologies look into active rectification. These rectification systems are to be used for the ac-to-dc conversion that comprises the first stage of the ac-to-ac conversion for applications such as motor drives in aircraft systems. Particular emphasis is given to a novel topology called Reduced Switching Element Matrix Inverter (RESEMI) which performs the ac-to-ac conversion with fewer switches than the matrix converters. The paper also presents system level solutions and compares qualitatively selected topologies.