Application of Fuzzy control algorithms for electric vehicle antilock braking/traction control systems

Abstract—The application of fuzzy-based control strategies has recently gained enormous recognition as an approach for the rapid development of effective controllers for nonlinear time-variant systems. This paper describes the preliminary research and implementation of a fuzzy logic based controller to control the wheel slip for electric vehicle antilock braking systems (ABSs). As the dynamics of the braking systems are highly nonlinear and time variant, fuzzy control offers potential as an important tool for development of robust traction control. Simulation studies are employed to derive an initial rule base that is then tested on an experimental test facility representing the dynamics of a braking system. The test facility is composed of an induction machine load operating in the generating region. It is shown that the torque-slip characteristics of an induction motor provides a convenient platform for simulating a variety of tire/road - driving conditions, negating the initial requirement for skid-pan trials when developing algorithms. The fuzzy membership functions were subsequently refined by analysis of the data acquired from the test facility while simulating operation at a high coefficient of friction. The robustness of the fuzzy-logic slip regulator is further tested by applying the resulting controller over a wide range of operating conditions. The results indicate that ABS/traction control may substantially improve longitudinal performance and offer significant potential for optimal control of driven wheels, especially under icy conditions where classical ABS/traction control schemes are constrained to operate very conservatively

Control strategies for blended braking in road vehicles. A study of control strategies for blended friction and regenerative braking in road vehicles based on maximising energy recovery while always meeting the driver demand.

In HEV and EV, higher fuel economy is achieved by operating the ICE and electric motor in the most efficient region and by using regenerative braking. Such a braking system converts, transfers, stores and reuses kinetic energy which would otherwise be dissipated as heat through friction brakes to the environment. This research investigates the control of braking for a mixed-mode braking system in a these vehicles based on the proportion of braking energy that can be stored. Achieving mixed-mode braking requires the ‘blending’ of the two systems (regenerative and friction), and in brake blending, the electric motor/generator (M/G) and the hydraulic actuation pressure are controlled together to meet the driver’s braking demand. The research presented here has established a new robust dynamic modelling procedure for the design of combined regenerative and hydraulic braking systems. Direct torque control and pressure control were selected as the control criteria in both brakes. Two simulation models have been developed in Matlab/Simulink to generate analysis the performance of the control strategy in the blended braking system. Integration of the regenerative braking system with ABS has also been completed, based on two conditions, with and without the deactivation of the regenerative braking. Verification of the models is presented, based on experimental work on two EVs manufactured by TATA Motors; the ACE light commercial vehicle and the VISTA small passenger car. It is concluded that braking demand and vehicle speed determine the operating point of the motor/generator and hence the regenerative braking ratio

Intelligent traction motor control techniques for hybrid and electric vehicles

This thesis presents the research undertaken by the author within the field of intelligent traction motor control for Hybrid Electric Vehicle (HEV) and Electric Vehicle (EV) applications. A robust Fuzzy Logic (FL) based traction motor field-orientated control scheme is developed which can control multiple motor topologies and HEV/EV powertrain architectures without the need for re-tuning. This control scheme can aid in the development of an HEV/EV and for continuous control of the traction motor/s in the final production vehicle. An overcurrent-tolerant traction motor sizing strategy is developed to gauge if a prospective motor’s torque and thermal characteristics can fulfil a vehicle’s target dynamic and electrical objectives during the early development stages of an HEV/EV. An industrial case study is presented. An on-line reduced switching multilevel inverter control scheme is investigated which increases the inverter’s efficiency while maintaining acceptable levels of output waveform harmonic distortion. A FL based vehicle stability control system is developed that improves the controllability and stability of an HEV/EV during an emergency braking manoeuvre. This system requires minimal vehicle parameters to be used within the control system, is insensitive to variable vehicle parameters and can be tuned to meet a vehicle’s target dynamic objectives

Medição indireta de torque e velocidade angular de motor de corrente contínua sem escovas

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Mecânica, Florianópolis, 2016.Em algumas aplicações de motores, como compressores herméticos de refrigeração, torque e velocidade angular são grandezas que podem oscilar significativamente durante uma revolução do eixo. A determinação dessas variações é de grande importância para assegurar eficiência ao motor e, no caso dos compressores, garantir conforto acústico ao usuário final. Quando o motor é interior a um invólucro selado, a determinação dessas grandezas por meio de instrumentação convencional é inviável e a obtenção delas a partir de variáveis externas se torna uma opção atraente. Resultados disponíveis na literatura indicam que é possível determinar o torque e a velocidade angular indiretamente em diferentes tipos de motores associados a compressores herméticos, entre eles os motores de corrente contínua sem escovas, que são alimentados por conversores eletrônicos. Neste trabalho, apresentase proposta de solução para determinação de torque e velocidade angular do motor de corrente contínua sem escovas a partir dos valores de tensão e correntes obtidas junto a tais conversores. Na proposta, baseada na modelagem matemática do motor de corrente contínua sem escovas, a tensão induzida é variável subjacente à estimação das grandezas de interesse, fazendo-se necessário obtê-la para qualquer posição angular do rotor. A avaliação dos valores estimados por meio da solução proposta demanda o desenvolvimento de uma bancada com características peculiares. Tal bancada deve possibilitar, de forma inédita, gerar e medir oscilações de torque com frequência igual à frequência rotacional, bem como medir a velocidade angular e tensão induzida do motor de corrente contínua sem escovas. A avaliação da solução proposta é feita pela comparação dos valores estimados com valores de referência obtidos em medição direta das variáveis nessa bancada. Tais testes mostraram a viabilidade da solução para todas as variáveis estimadas, com curvas de tendência de tensão induzida e velocidade angular que se assemelham às de referência.Abstract : In some electrical motors applications such as hermetic refrigeration compressors, torque and angular rate are quantities that can fluctuate significantly during an axis revolution. The determination of these variations is of great importance to ensure efficiency to the motor and, in the case of compressors, to guarantee acoustic comfort to the end user. When the motor is inside a sealed enclosure, the determination of these quantities by means of conventional instrumentation is impracticable and obtaining them from external variables becomes an attractive option. Results available in the literature indicate that it is possible to determine the torque and angular rate indirectly in different types of motors associated with hermetic compressors, among them the brushless DC motors, which are fed by electronic converters. In this work, we propose a solution for determination of torque and angular rate of the BLDC from the voltage and current values obtained with such converters. In the proposal, based on the mathematical modeling of the BLDC, the back electromotive force is variable underlying the estimation of the quantities of interest, making necessary to obtain it for any angular position of the rotor. The evaluation of the estimated values through the proposed solution demands the development of a bench with peculiar characteristics. Such a bench should enable, in a novel way, to generate and measure torque oscillations with frequency equal to the rotational frequency, as well as to measure the angular rate and induced voltage of the BLDC. The evaluation of the proposed solution is made by comparing the estimated values with reference values obtained in direct measurement of the variables in this bench. These tests showed the viability of the solution for all the estimated variables, with curves of back electromotive force and angular rate that resemble those of the reference

Electric Vehicle Efficient Power and Propulsion Systems

Vehicle electrification has been identified as one of the main technology trends in this second decade of the 21st century. Nearly 10% of global car sales in 2021 were electric, and this figure would be 50% by 2030 to reduce the oil import dependency and transport emissions in line with countries’ climate goals. This book addresses the efficient power and propulsion systems which cover essential topics for research and development on EVs, HEVs and fuel cell electric vehicles (FCEV), including: Energy storage systems (battery, fuel cell, supercapacitors, and their hybrid systems); Power electronics devices and converters; Electric machine drive control, optimization, and design; Energy system advanced management methods Primarily intended for professionals and advanced students who are working on EV/HEV/FCEV power and propulsion systems, this edited book surveys state of the art novel control/optimization techniques for different components, as well as for vehicle as a whole system. New readers may also find valuable information on the structure and methodologies in such an interdisciplinary field. Contributed by experienced authors from different research laboratory around the world, these 11 chapters provide balanced materials from theorical background to methodologies and practical implementation to deal with various issues of this challenging technology. This reprint encourages researchers working in this field to stay actualized on the latest developments on electric vehicle efficient power and propulsion systems, for road and rail, both manned and unmanned vehicles

Intelligent sensorless antilock braking system for brushless in-wheel electric vehicles

Brushless motors are increasingly used in different designs of in-wheel electric vehicles (EVs). In this paper, a sensorless antilock braking system (ABS) for brushless-motor in-wheel EVs is proposed. The proposed solution omits the need for installation of separate conventional ABS sensors at each corner of the vehicle. This paper also shows, both theoretically and experimentally, that the general form of a conventional ABS sensor output voltage is identical to a brushless dc (BLDC)-motor back electromotive force. The proposed sensorless system can reduce the costs of manufacturing and maintenance of the vehicle and significantly improves the performance of the ABS by accurate wheel speed estimation and road identification using wavelet signal processing methods. The sensorless system was extensively tested using actual ABS hardware. Those experiments showed that the accuracy of the proposed sensorless wheel speed estimation for BLDC propulsion was higher than that of commercial ABS sensors. In addition, sensorless ABS for brushless propulsion was compared with that of brushed dc motor, and the results showed that the brushless sensorless ABS achieved better accuracy, robustness, and reliability compared with the sensorless ABS for brushed dc motor

Advanced Strategies for Robot Manipulators

Amongst the robotic systems, robot manipulators have proven themselves to be of increasing importance and are widely adopted to substitute for human in repetitive and/or hazardous tasks. Modern manipulators are designed complicatedly and need to do more precise, crucial and critical tasks. So, the simple traditional control methods cannot be efficient, and advanced control strategies with considering special constraints are needed to establish. In spite of the fact that groundbreaking researches have been carried out in this realm until now, there are still many novel aspects which have to be explored