Chester Coomer

Evaluation of the 2010 Toyota Prius Hybrid Synergy Drive System

Subsystems of the 2010 Toyota Prius hybrid electric vehicle (HEV) were studied and tested as part of an intensive benchmarking effort carried out to produce detailed information concerning the current state of nondomestic alternative vehicle technologies. Feedback provided by benchmarking efforts is particularly useful to partners of the Vehicle Technologies collaborative research program as it is essential in establishing reasonable yet challenging programmatic goals which facilitate development of competitive technologies. The competitive nature set forth by the Vehicle Technologies Program (VTP) not only promotes energy independence and economic stability, it also advocates the advancement of alternative vehicle technologies in an overall global perspective. These technologies greatly facilitate the potential to reduce dependency on depleting natural resources and mitigate harmful impacts of transportation upon the environment.

A novel wireless power transfer for in-motion EV/PHEV charging

Wireless power transfer (WPT) is a convenient, safe, and autonomous means for electric and plug-in hybrid electric vehicle charging that has seen rapid growth in recent years for stationary applications. WPT does not require bulky contacts, plugs, and wires, is not affected by dirt or weather conditions, and is as efficient as conventional charging systems. When applied in-motion, WPT additionally relives range anxiety, adds further convenience, reduces battery size, and may help increase the battery life through charge sustaining approach. This study summarizes some of the recent activities of Oak Ridge National Laboratory (ORNL) in WPT charging of EV and PHEVs inmotion. Laboratory experimental results that highlight the wireless transfer of power to a moving receiver coil as it passes a pair of transmit coils and investigation of results of insertion loss due to roadway surfacing materials. Some of the experimental lessons learned are also included in this study.

Demonstrating Dynamic Wireless Charging of an Electric Vehicle: The Benefit of Electrochemical Capacitor Smoothing

The wireless charging of an electric vehicle (EV) while it is in motion presents challenges in terms of low-latency communications for roadway coil excitation sequencing and maintenance of lateral alignment, plus the need for power-flow smoothing. This article summarizes the experimental results on power smoothing of in-motion wireless EV charging performed at the Oak Ridge National Laboratory (ORNL) using various combinations of electrochemical capacitors at the grid side and in the vehicle. Electrochemical capacitors of the symmetric carbon-carbon type from Maxwell Technologies comprised the in-vehicle smoothing of wireless charging current to the EV battery pack. Electro Standards Laboratories (ESL) fabricated the passive and active parallel lithium-capacitor (LiC) unit used to smooth the grid-side power. The power pulsation reduction was 81% on the grid by the LiC, and 84% on the vehicle for both the LiC and the carbon ultracapacitors (UCs).

Evaluation of the 2007 Toyota Camry Hybrid Synergy Drive System

The U.S. Department of Energy (DOE) and American automotive manufacturers General Motors, Ford, and DaimlerChrysler began a five-year, cost-shared partnership in 1993. Currently, hybrid electric vehicle (HEV) research and development is conducted by DOE through its FreedomCAR and Vehicle Technologies (FCVT) program. The mission of the FCVT program is to develop more energy efficient and environmentally friendly highway transportation technologies. Program activities include research, development, demonstration, testing, technology validation, and technology transfer. These activities are aimed at developing technologies that can be domestically produced in a clean and cost-competitive manner. Under the FCVT program, support is provided through a three-phase approach [1] which is intended to: • Identify overall propulsion and vehicle-related needs by analyzing programmatic goals and reviewing industry’s recommendations and requirements, then develop the appropriate technical targets for systems, subsystems, and component research and development activities; • Develop and validate individual subsystems and components, including electric motors, emission control devices, battery systems, power electronics, accessories, and devices to reduce parasitic losses; and • Determine how well the components and subassemblies work together in a vehicle environment or as a complete propulsion system and whether the efficiency and performance targets at the vehicle level have been achieved. The research performed in this area will help remove technical and cost barriers to enable technology for use in such advanced vehicles as hybrid electric, plug-in hybrid electric, electric, and fuel-cell-powered vehicles.

Oak Ridge National Laboratory Wireless Power Transfer Development for Sustainable Campus Initiative

Wireless power transfer (WPT) is a convenient, safe, and autonomous means for electric and plug-in hybrid electric vehicle charging that has seen rapid growth in recent years for stationary applications. WPT does not require bulky contacts, plugs, and wires, is not affected by dirt or weather conditions, and is as efficient as conventional charging systems. This study summarizes some of the recent Sustainable Campus Initiative activities of Oak Ridge National Laboratory (ORNL) in WPT charging of an on-campus vehicle (a Toyota Prius plug-in hybrid electric vehicle). Laboratory development of the WPT coils, high-frequency power inverter, and overall systems integration are discussed. Results cover the coil performance testing at different operating frequencies, airgaps, and misalignments. Some of the experimental results of insertion loss due to roadway surfacing materials in the air-gap are presented. Experimental lessons learned are also covered in this study.

Evaluation of the 2008 Lexus LS 600H Hybrid Synergy Drive System

Subsystems of the 2008 Lexus 600h hybrid electric vehicle (HEV) were studied and tested as part of an intensive benchmarking effort carried out to produce detailed information concerning the current state of nondomestic alternative vehicle technologies. Feedback provided by benchmarking efforts is particularly useful to partners of the Vehicle Technologies collaborative research program as it is essential in establishing reasonable yet challenging programmatic goals which facilitate development of competitive technologies. The competitive nature set forth by the Vehicle Technologies program not only promotes energy independence and economic stability, it also advocates the advancement of alternative vehicle technologies in an overall global perspective. These technologies greatly facilitate the potential to reduce dependency on depleting natural resources and mitigate harmful impacts of transportation upon the environment.

Effect of Side Permanent Magnets for Reluctance Interior Permanent Magnet Machines

A traditional electric machine uses two dimensional magnetic flux paths in its rotor. This paper presents the development work on the utilization of the third dimension of a rotor. As an example, the air gap flux of a radial gap interior permanent magnet motor can be significantly enhanced by additional permanent magnets (PM) mounted at the sides of the rotor. A prototype motor built with this concept provided higher efficiency and required a shorter stator core length for the same power output as the Toyota/Prius traction drive motor.

Report on Toyota/Prius Motor Torque Capability, Torque Property, No-Load Back EMF, and Mechanical Losses, Revised May 2007

In todays hybrid vehicle market, the Toyota/Prius drive system is currently considered the leader in electrical, mechanical, and manufacturing innovations. It is significant that in todays marketplace, Toyota is able to manufacture and sell the vehicle for a profit. This projects objective is to test the torque capability of the 2004 Prius motor and to analyze the torque properties relating to the rotor structure. The tested values of no-load back electromotive force (emf) and mechanical losses are also presented.

A New Manufacturing Technology for Induction Machine Copper Rotors

The benefits of energy and operational cost savings from using copper rotors are well recognized. The main barrier to die casting copper rotors is short mold life. This paper introduces a new approach for manufacturing copper-bar rotors. Either copper, aluminum, or their alloys can be used for the end rings. Both solid-core and laminated-core rotors were built. High quality joints of aluminum to copper were produced and evaluated. This technology can also be used for manufacturing aluminum bar rotors with aluminum end rings. Further development is needed to study the life time reliability of the joint, to optimize manufacturing fixtures, and to conduct large-rotor tests.