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Electric motor whine is one of the main noise sources of electric vehicles (EVs). Without engine masking noise, high pitch tonal noise from electric motor can be highly annoying and raise sound quality issues for electrified propulsion systems. This paper describes a patented new technology that controls electric motor to actively mask annoying high-pitch tonal noise by (i) controlling electric motor to create complementary low order tones to enrich sound complexity and distract high pitch tones; (ii) controlling motor to generate random dithering noise to raise masking noise floor and reduce tone-to-noise ratio around tonal targets; (iii) combining complementary injection at low frequency and dithering at high frequency for enhanced masking. This new technology enables controlling masking noise level, frequency, order and bandwidth as a function of motor torque and speed for most effective masking.

Electric motor whine is one of the main noise sources of hybrid and electric vehicles. Motor air gap eccentricity due to propulsion system deflection, part tolerances and manufacturing variation is typically ignored in motor NVH design and analysis. Such eccentricity can be a dominant noise source by amplifying critical motor whine orders up to 10 dB, leading to poor NVH robustness. However, this problem cannot be explained by conventional method based on symmetric 2D approach. New 3D electromagnetic (EM) and NVH analyses are developed and validated to accurately predict air gap induced motor noise to enhance NVH robustness: First, a true 3D full 360-degree electric motor model is developed to model asymmetric air gap distribution along motor stack length. Predicted 3D EM forces are mapped to mechanical finite-element mesh over the cylindrical stator surface.

Wireless power transfer (WPT) of plug-in and battery electric vehicles (PEV�s) rely on loosely coupled transformer operating in magnetic resonance to tune out reactive effects. Depending on the degree of coupling, such systems experience a single peak response that trends to bifurcate as the coefficient of coupling increases. This places additional burden on the WPT grid side power controller to not only manage the power transfer process but to manage the transmit coil to receiver coil reactive power in response to vehicle ground clearance and misalignment tolerance. In addition, the WPT rectified output voltage must dynamically match the vehicle on-board regenerative energy storage system (RESS). This paper examines the essentials of WPT operation and challenges facing the commercialization of wireless charging. Experimental results obtained from the Oak Ridge National Laboratory WPT apparatus are presented as validation of the theory. Presenter John Miller, ORNL

The classical approach to prepare engine exhaust emissions control systems for evaluation and certification is to condition the fresh parts by aging the systems on an engine/dynamometer aging stand. For diesel systems this can be a very lengthy process since the estimated service life of the emissions control systems can be several hundred thousand miles. Thus full useful life aging can take thousands of engine bench aging hours, even at elevated temperatures, making aging a considerable cost and time investment. Compared to gasoline engines, diesel engines operate with very low exhaust gas temperatures. One of the major sources of catalyst deactivation is exposure to high temperature [ 1 ].

Demands on energy storage systems are as diverse as the applications served. This paper considers several such examples that benefit from use of ultracapacitors.

Lithium ion batteries are superior to NiMH batteries in energy density, but have been excluded from the highest power density applications due to safety and cost limitations. The cathode materials in conventional lithium ion cells are based on metal oxide materials, typically containing nickel or cobalt. These nickel and cobalt based cathode materials are expensive and reactive with the electrolyte. Metal oxides are electronic insulators, which can limit the rate performance of lithium ion cells. The open circuit potential of conventional metal oxide electrodes is relatively high. This limits the charge acceptance rate, since the polarization under high rate charging (> 10C) can exceed the potential limit of the electrolyte. Similarly, the open circuit potential of conventional graphitic anode materials is close to the lithium plating potential which also limits high charge rate acceptance.