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The traction motor is key to the �synergy of the electric powertrain�, the overall functionality of the battery, e-motor, power control electronics, and charging system. Therefore some automakers have decided to design, develop, and produce their traction motors in house while some others are working with suppliers for their electric power train motors. Off-the-shelf motors, no matter how extensively they are adapted for a specific application, can compromise the efficiencies of the propulsion system. Presenter Marc Winterhoff, Roland Berger Strategy Consultants

This paper proposes a current limits distribution control strategy for a parallel hybrid electric vehicle (parallel HEV) which includes an advanced powertrain concept with two electrical driving axles. One of the difficulties of an HEV powertrain with two electrical driving axles is the ability to distribute the electrical current of one high voltage battery appropriately to the two independent electrical motors. Depending on the vehicle driving condition (i.e., car maneuver) or the maximization of the entire efficiency chain of the system, a suitable control strategy is necessary. We propose an input-output feedback linearization strategy to cope with the nonlinear system subject to input constraints. This approach needs an external, state dependent saturation element, which translates the state dependent control input saturation to the new feedback linearizing input and therefore preserves the properties of the differential geometric framework.

Who are the people who know the most about the buses in your fleet? They are most likely the operators and the servicing technicians. They are also the key people whose knowledge, level of training and attitude can determine the success or failure of new powertrain technologies. Training and recruitment of both need to be held to a higher standard than we have seen in the past. I will argue that even the culture of those involved in fleet operations needs to be changed. The bar for technical competence and product knowledge needs to be raised for operators and technicians. In return managers should find ways to include them as stakeholders, investing them with both additional responsibility and accountability. This will require greater access to training and recognition of achievement. Where are the busses stored and serviced? Most likely in an all-purpose state/county/municipal service facility servicing a variety of equipment.

Abstract To gain a better understanding of the characteristics of corrugation, including the development and propagation of corrugation, and impact of vehicle and track dynamics, a computational model was established, taking into account the nonlinearity of vehicle-track coupling. The model assumes a fixed train speed of 300 km/h and accounts for vertical interaction force components and rail wear effect. Site measurements were used to validate the numerical model. Computational results show that (1) Wheel polygonalisation corresponding to excitation frequency of 545-572 Hz was mainly attributed to track irregularity and uneven stiffness of under-rail supports, which in turn leads to vibration modes of the bogie and axle system in the frequency range of 500-600 Hz, aggregating wheel wear. (2) The peak response frequency of rail of the non-ballasted track coincides with the excitation frequency of wheel-rail coupling; the resonance results in larger wear amplitude of the rail.

This activity is focused on more electric and all electric type power systems for air vehicles. The scope of which includes source, distribution and user contributions to electrical power quality, failure modes, coordination, system reliabilty and robustness, impacts of being flight critical and the gaps which exist in present standards and guidance documents.

The purpose of this AIR is to provide a comprehensive description document that displays various examples of low pressure seals and wipers utilized within mechanical and electromechanical actuators. The document is intended as an overview for those specifying or designing actuators in order to compare existing solutions as reference for implementation.

This SAE Aerospace Information Report is intended to provide advanced methods for wire selecting and sizing in aerospace application as a continuation of AIR6540, Fundamentals in Wire Selection and Sizing for Aerospace Applications. Also, it will provide valuable information for the electrical design engineer to verify the proper wire selection and validate a set of system design requirements which includes meeting environmental and installation constraints.

EPS stability is an essential property that defines EPS ability to provide secure operation under required range of operation scenario. Power system stability is defined as “the ability of an electric power system, for a given initial operating condition, to regain a state of operating equilibrium after being subjected to a physical disturbance, with most system variables bounded so that practically the entire system remains intact”. This is applicable for AC and DC systems and has to address steady state conditions, transient conditions as well as high power loads connection / disconnection on the network.

The need for developing this standard is driven by the quickly evolving field of electrified propulsion for aircraft. Industry is moving forward in development of a broad range of high voltage primary power systems. There is an immediate need to standardize power quality requirements for design, analysis, verification, and testing for these types of systems.

Technical requirements especially related to the design and construction and the minimum performance requirements (including qualification test conditions) for PM motors and power converters (operated as VFDs) used as the prime mover for more-electric, hybrid-electric, and fully-electric aircraft propulsion systems.

The document provides a definition of skew and disconnect occuring in high lift systems in flight controls including their hazard assessment, describes generic solutions and provides a for specifying requirements.

Scope: This Aerospace Recommended Practice (ARP) provides guidelines for specifying dielectric withstanding strength and insulation resistance design and test requirements for aircraft line replaceable units (LRU's) used within a flight control and/or a utility system. 1.1 Purpose The testing is intended to verify that an LRU can operate safely at its rated voltage and withstand momentary over potentials due to switching, troubleshooting testing, surges, etc.. The testing is also intended to verify adequate design margin of the insulation system and detect workmanship problems.

This SAE Aerospace Recommended Practice (ARP) is intended as a guide to define the requirements for aerospace hydraulic shuttle valves, including details pertinent to the design, performance, fabrication, and testing of the shuttle valves.

This Aerospace Recommended Practice (ARP) offers guidelines for specifying servoloop pressure feedback transducers for use in hydraulic actuation for servosystems.

1. SCOPE This Aerospace Recommended Practice (ARP) provides recommendations for the design and test requirements for hydraulic priority valves. The hydraulic priority valve is intended for use in a civil or a military aircraft hydraulic system with a rated system pressure up to 5000 psi (34500 kPa). 1.1 Purpose The recommended requirements contained in this document are compiled for inclusion in a Procurement Specification for a hydraulic priority valve. NOTE: The recommended requirements in this ARP should be reviewed by the Purchaser or the Contractor and only those requirements that are applicable for a specific application should be incorporated in the Procurement Specification. 1.2 Classification The hydraulic priority valve types covered by this ARP are: • The line-mounted type - a valve with standard fitting ends • The cartridge type - a cylindrical valve with O-ring glands for mounting in a manifold, for example

This AIR intends to better document and tabulate electrical load dynamics that influence power source capacity, power quality and stabiltiy.

Recommendation Guidelines and Practices for the Design and Validation of EHA Thermal Management Considerations, particularly for Low Temperature Operation.

To determine the end-of-life criteria of electrical insulation materials and components and predict insulation life in high voltage aviation applications

To provide test guidelines, recommendations and referenced standards for insulation materials in a high energy system especially at high voltages (AC, DC and PWM) and at high altitudes, in the purpose of defining/measuring the effects of insulation ageing.