Designing regenerative braking strategies for electric vehicles with an efficiency map

Regenerative braking can lead to an extension of 10 to 25% of a vehicle's range in urban driving. The goal is to define acceptable regenerative torque strategies from an efficiency map of the regenerated energy versus the vehicle's speed, and the kind of road (dry, wet, snow, ...). The method designs the regenerative braking strategy by taking into account all losses. It is applied to a prototype of a recreational 3-wheel rear-wheel drive hybrid vehicle. The electrical motor is linked to the rear wheel with a belt and gears. A longitudinal model of the vehicle is simulated with Matlab/Simulink. The simulated global efficiency map is obtained by applying different regenerative torques and computing the ratio of the incoming battery power to the extracted kinetic power. Experimental measurements give the electrical motor efficiency and the mechanical parameters. An experimental global efficiency map can then be evaluated from those measurements. The optimal regenerative strategy is the one which maximizes the global efficiency for each speed. Simulations show that the designed strategy recaptures more energy than the usual strategies proposed in the literature. The efficiency map also shows that several strategies are acceptable on dry asphalt roads. This is confirmed by some measurements: a deceleration chosen between 2 and 3 m/s2 regenerates almost the same amount of energy (from 65% to 73% of the kinetic energy). Experimental measurements and simulations prove that there is not only one optimal strategy but several acceptable strategies which can be deduced from the global efficiency map. The regenerative torque can then be modified while maintaining an acceptable recapturing efficiency level. Future work will focus on online updating of the map and on designing a slip controller to maintain vehicle stability on slippery roads

Conception et optimisation d'un transducteur électrodynamique pour la récupération d'énergie vibratoire

BESANCON-BU Sciences Staps (250562103) / SudocSudocFranceF

Optimisation d'une contre-réaction électromagnétique pour la récupération d'énergie vibratoire

International audienc

Scavenging energy from a vibrating beam using an electromagnetic transducer

18-21 juinInternational audienc

Optimization of the power flow extracted from a flexible structure using a control approach

International audienceVibrating energy is a renewable energy that can be used to power wireless transducers. This article presents analytical and numerical results that put forward design parameters for optimizing the energy conversion from mechanical vibration to electrical power with an electromagnetic transducer. The studied structure is a flexible structure using an electromagnetic transducer connected to a resistive feedback loop. This passive harvesting circuit is a simplified representation of the storing system usually including a battery and a rectifying electronic. Here the energy harvesting strategy chosen creates an additional viscous damping on the structure. The numerical model of the generator, including the coupling law, predicts the power transferred between electrical and mechanical energies. For a purely resistive feedback, the study of the harvested energy shows that harvesting and stabilization strategies are different. A simple analytical model, derived from modal synthesis techniques, shows that Jacobi’s maximal power transfer theorem can be adapted for multi-physic problems: the electrical and mechanical damping ratios have to be matched to maximize the power transferred. This result is confirmed by experimental measurements. The analytical study also shows that it is possible to use the root locus to choose the two optimal energy harvesting feedback gains and then consequently the harvesting electronic circuit’s parameters

ILC Reference Design Report Volume 4 - Detectors

This report, Volume IV of the International Linear Collider Reference Design Report, describes the detectors which will record and measure the charged and neutral particles produced in the ILC's high energy e+e- collisions. The physics of the ILC, and the environment of the machine-detector interface, pose new challenges for detector design. Several conceptual designs for the detector promise the needed performance, and ongoing detector R&D is addressing the outstanding technological issues. Two such detectors, operating in push-pull mode, perfectly instrument the ILC interaction region, and access the full potential of ILC physics.This report, Volume IV of the International Linear Collider Reference Design Report, describes the detectors which will record and measure the charged and neutral particles produced in the ILC's high energy e+e- collisions. The physics of the ILC, and the environment of the machine-detector interface, pose new challenges for detector design. Several conceptual designs for the detector promise the needed performance, and ongoing detector R&D is addressing the outstanding technological issues. Two such detectors, operating in push-pull mode, perfectly instrument the ILC interaction region, and access the full potential of ILC physics