Electric Braking Research Articles

Energy Efficiency Improvement with Reversible Substations for Electrified Transportation Systems

More and more often overall energy efficiency of an electrified transportation system appears as target of new constructions, sometimes with incomplete definitions of performance indexes to assess that target has been reached. A worked out example is based on the introduction of reversible substations. Reversible substations are a method to improve energy efficiency, whose application in an existing system can be progressive and does not require large traffic intensity to be effective. Their effectiveness depends on some system parameters (nominal catenary voltage in particular). A simulation model fed with experimental data from a line section of Metro de Madrid is used to demonstrate the operation and optimization of reversible substations. Background The ambitious reduction of CO2 greenhouse gas emission within 2050 declared by the European Commission also involves transportation systems. In this context an optimum recovery of the electric braking energy produced by railway vehicles is more and more relevant. Several strategies to completely recover the braking energy are being developed and applied. A methodology that allows the accurate determination of the amount of recovered energy in real operating conditions becomes then a valuable tool. Objective Reversible substations are one of the braking energy recovery methods that are widely applicable. Their effect is analyzed in a system perspective, considering them integrated in the transportation system with its dynamics and various operating points. The effectiveness and consequences of the operation of one or more reversible substations are evaluated by identifying relevant system conditions and scenarios. Methods An electric network model is provided, fed by measured timetable and traction current. Simulation results are analyzed and compared with some experimental results: simulation configurations will be selected to match those of the available experimental data. Results The selected substation no-load output voltage level has a significant effect on efficiency and performance of reversible substations. A reduction of 50 V, from 1700 V to 1650 V produces a decrease of the energy dissipated by the braking rheostat on-board trains of about 13%. The voltage increase caused during braking phases is kept under control better for track positions close to reversible substations: tests show that line voltage increase is 2.5% of nominal value with a reversible substation, and only 0.5% when it is operated. Trimming the thresholds that trigger the operation of the on-board braking chopper (intermingling regenerative and dissipative braking) has a dramatic effect on regenerability: a reduction of 50 V causes an improvement of 19%. Conclusion The paper presents a methodology that merges measurements and circuital model to investigate on the energy saving provided by reversible substations supplying railway system. The methodology has been applied to a real case. Preliminary results regarding the impact of supply voltage level, reversible module position and threshold levels of the braking chopper control system on the dissipated braking energy and power quality has been carried out.

Research Results of the Operating Efficiency of the Electric Train Brake Air System

This document discusses the identified problems of the electric train braking system operation in the autumn-winter period. The results of observations are presented. The results of calculating the amount of condensate released during the 1 hour of compressor operation at a certain ambient air temperature are presented. Engineering calculations were performed. A technical solution is proposed to improve the efficiency of pneumatic equipment by installing heated purge valves on the main instead of conventional valves to prevent freezing.

Analytical Modeling of Heat Transfer Coefficient Analysis in Dimensionless Number of an Electric Parking Brake Using CFD

The present study intends the development of an electric parking brake (EPB) for commercial vehicles (CVs). CVs with EPB applications are currently available in an entirely different set of issues than EPB applications on passenger cars, which are presently widely used. Safe parking requires much more focus with an order of magnitude, more thermal capacity, brake mass, and clamp pressures. In the first instance, heat loss from the brake disc was estimated. The investigations also allowed for precise prediction of radiative heat loss by defining surface emissivity. The parameters of air movement, convective heat transfer coefficients, and velocities were investigated, and validation was done with the CFD model. When the temperature dropped to 252 °C, the maximum estimated value of the Nusselt number was 72.25. Nusselt number pattern that looks identical over the arc surface yields 13.38 percent better results. Nu values at maximum temperature were calculated to be 80.5 and 82.6 at 251.8 °C. The “hconv” value was 4.1 percent lower than in the arc region, with the highest value at 400°C being 11.5 W/m2K. The present study adopted unique approach and obtained brake disc temperature and the coefficient of convective heat transfer on disc friction surfaces and hat regions. CFD modeling was done during the cooling phase to evaluate flow patterns and “hconv” fluctuation across the entire disc brake surface area. The mathematical modeling and adopted methodology for computing heat transfer coefficients for different disc regions have helped to better understand of a CV brake disc heat dissipation.

ОБҐРУНТУВАННЯ КОНСТРУКТИВНИХ ТА ЕКСПЛУАТАЦІЙНИХ ВИМОГ ДО ПІДЙОМНИКА ДЛЯ ОБСЛУГОВУВАННЯ ОПОР ВУЛИЧНОГО ОСВІТЛЕННЯ

The article is an overview, and the presented information is of an overview nature and is dedicated to the justification of the choice of component parts of the selected structure of mechanized lifts for servicing street lighting poles. The purpose is to consider the shortcomings of the chosen analogue and to justify the components of the chosen design of the wheel lift, namely each individual part of it, which should ensure operation on street lighting poles with poles of different cross-sections. The main structural and operational requirements for the component parts of the selected lift structure were determined, namely: the lift components must be reliable, quickly reconfigurable in the field and without the use of special tools; the fastening of the wheels to the frame must be reliable and durable enough to withstand a heavy load; wheels must withstand large tangential loads, have good grip on the surface supports; brakes must meet certain requirements; the manipulator must be so reliable that it is possible to lift not only tools and equipment, but also a person, be compact and have enough controlled degrees of movement to easily fold down to the smallest possible dimensions; weight and size characteristics should allow its transportation in cargo or cargo-passenger vehicles of category "B" and above, as well as on trailers (semi-trailers) to them. Deficiencies of the existing design are identified and changes to the design details are proposed. Special attention is paid to brakes. Among the existing brakes are: disc brakes, drum brakes, foot brakes, regenerative brakes and electronic brakes. Disk ones were chosen. Types of brakes are arranged in order of efficiency types of electric scooter brakes. Therefore, taking into account the advantages and disadvantages of each type of b rake, disc brakes were chosen. The wheels themselves must be selected according to the following parameters: they must withstand a large tangential load, tires and the pressure in them must be selected so that there is good engagement with the support, a diameter of 11 inches.

Experimentation of a device collecting at source airborne particles issued from rolling stocks brakes systems

A specific air quality exists in underground railway stations, influenced by railways operations as infrastructure wears, mechanical braking or station design and ventilation. Among solutions existing to improve the air quality (air treatment in the station; use of less emissive brake shoes and pads, increase of electrical braking), the study focuses on a device collecting at source airborne particles issued from trains brake systems. A groove pattern of braking pads has been designed with finite element distortion analysis, air flow circuit optimisation and tested on a braking bench equipped with sensors to characterise the particles emitted and the braking performances under standardised conditions. Above 70% reduction of emissions has been noted. A suburban train bogie has then been equipped to evaluate the reliability and maintainability of the device on commercial service conditions.

Extremum Seeking Based Braking Torque Distribution for Electric Vehicles’ Hybrid Anti-lock Braking System

To ensure braking stability and maximize energy recovery, electric vehicles combine two braking modes, friction and regenerative braking. This paper proposes a novel braking torque distribution (BTD) algorithm between frictional/regenerative brake systems. Security and regeneration energy are the two main issues in braking torque allocation design. Based on the extremum search (ES) technique, the objectives and constraints of the hybrid ABS brake torque distribution are well handled. The offered BTD can maximize the regeneration energy and improve the battery's state of charge (SOC) by optimizing the electric braking system efficiency, while respecting the braking actuators constraints. The validity and effectiveness of the proposed BTD has been demonstrated by simulation in the MATLAB/Simulink environment.

Определение сопротивления в цепи тяговых электродвигателей по данным микропроцессорных систем управления

Purpose: To develop methodology for determining the actual resistance of traction electric drive (TED) circuits of a locomotive with electric power transmission and with refined calculation of voltage losses of a collector-brush apparatus according to microprocessor control system data. These data are necessary for calculating actual traction characteristics of a locomotive as well as its braking characteristics in electric braking modes. Methods: Methods of electric machine theory, statistical processing and regression analysis of experimental data were used. Results: Based on the statistical analysis of registration data of on-board diagnostics subsystem of 20 sections of 2TE116U and TEP70BS diesel locomotives, methods for determining resistance factual value for traction electric drive circuit as well as methods of refined calculation for voltage losses in a collector-brush apparatus are proposed and justified. The hypothesis on distribution normal law for the value of resistance and the possibility to use its mathematical expectation as an estimated value is confirmed. The limits of resistance possible changes for TED circuits of diesel locomotives 2TE116U and TEP70BS have been established. Practical significance: The results obtained allow us to clarify energy loss amounts in a locomotive traction drive when calculating its traction and braking characteristics. Data on the limits, allowed in exploitation, of active resistance change for TED serviceable chains may be used for operative diagnostics of locomotive power circuit.

Coordinated Control Strategy of Electro-Hydraulic Composite Braking Torque for the Distributed Electric Vehicles

The difference in response to electric and hydraulic braking causes sudden changes in braking torque during braking mode switching. An electro-hydraulic composite braking system’s dynamic torque coordination control strategy is proposed under braking mode switching conditions. By establishing the dynamic response model of the electro-hydraulic braking system (EHB), the key factors affecting the response speed of the EHB are analyzed, and the dynamic fuzzy controller for the pressure regulation of the brake wheel cylinder is designed. At the same time, the nonlinearity and hysteresis in the hydraulic braking process are considered, as well as electrical brake response overshoots. The electric brake response model is established, and the PID controller with feedforward feedback is designed to control the motor to adjust the inertia overpressure or lag pressure deficiency in the hydraulic braking process. Finally, the simulation verification is carried out; the results show that the proposed strategy can increase the hydraulic brake response speed by 25.4%, the impact degree of the vehicle is not more than 6.25 GB, and the hydraulic steady state error does not exceed 2.3%, which improves the vehicle ride comfort under braking mode switching.

Research on Composite Braking Mode Switching Strategy Based on Fuzzy Algorithm

AbstractAiming at the cruising range of electric vehicles, this paper proposes a control strategy for electric vehicle electromechanical composite braking mode switching based on motor braking force correction. The braking force of the motor is adjusted by factors such as braking intensity to improve the braking energy recovery, and the braking force distribution curve is designed considering the braking energy and braking safety and stability. The research results show the braking time, braking torque, and battery charge. The peak value of discharge current has been improved, and the braking energy recovery efficiency has increased by 9.17% and 3.32% respectively under different working conditions. Under different braking modes with an initial speed of 30 km h−1, the braking energy recovered by the battery has increased by 16.04 , 3.89, 9.63 kJ, the braking time and braking distance are also shorter, which highlights the superiority of this control strategy.

Research on fuzzy control strategy of PMSM electric braking considering state constraints

The PMSM drive system is widely used in new energy vehicles, and the rational design of the electric braking control strategy can maximize the recovery of energy during the braking process of the vehicle and improve the energy utilization rate of the vehicle. This paper firstly analyzes the energy system architecture of PMSM driving electric vehicle. Then the braking range, braking intensity and vehicle speed are classified and the braking intention is accurately identified based on the fuzzy control strategy. And, the braking strategy is modified by considering the braking constraints of the PMSM and the state constraints of the power battery. Finally, a test platform is built to verify the designed control strategy under six typical braking conditions.

Research on Electric Control Brake System Based on Railway Vehicle

The trackless train may be mixed with other vehicles in the city. Therefore, developing a vehicle braking system with high reliability, fast response, and powerful braking force is necessary. In this research, the chip module control is added to each control part to realize rapid electric signal collection and response, and then the pneumatic control of each actuator is used to realize rapid and flexible electric braking control of the vehicle. The braking system has been tested on the test bench in the factory, and its response speed and braking effect have increased by 10% compared with the traditional bus braking system. When the performance test is carried out on the real vehicle, the braking effect is also improved by nearly 10%. Through the design of the braking system, the braking system of domestic trackless trains can be perfectly solved.

Fault-Tolerant Design Process of Spoke-Type IPM Motor Considering Irreversible Demagnetization of PM in Integrated Electric Brake System

In this article, a novel fault-tolerant design process of the spoke-type interior permanent magnet (IPM) motor is proposed to prevent the increase of cogging torque and torque ripple due to partial demagnetization fault and to minimize the motor size. First, unlike other research papers on the irreversible partial irreversible demagnetization of permanent magnet (PM), in this article, the effect of partial irreversible demagnetization faults on the cogging torque and torque ripple for the fault cases is investigated. Then, a novel fault-tolerant design process is proposed to solve the problem of partial demagnetization faults that increase the cogging torque and torque ripple. In the novel fault-tolerant design process, first, to solve the problem of increasing cogging torque and torque ripple due to the partial demagnetization fault, a process for implementing a uniform irreversible PM demagnetization is proposed. Second, to compensate for the motor torque constant decreased by degraded PM, which is caused by irreversible demagnetization of PM, a torque compensation coefficient is also proposed. The proposed fault-tolerant design process is applied to the motor design for the integrated electric brake (IEB) system that requires high torque density. In the optimal design process, Latin hypercube sampling (LHS), a kriging method, and a genetic algorithm are utilized. To verify the effectiveness of the proposed fault-tolerant design process, it is compared with the conventional optimized design results in which irreversible demagnetization of PM is not allowed at all to prevent the partial demagnetization faults. As a result of comparing the optimal design results, the proposed optimization model utilizing the fault-tolerant design process can significantly reduce the motor volume by 12.9%, compared to the conventional optimization model.

Analysis of Heat Generation on Unipolar Axial Eddy Current Brake Disc and Its Effect on Braking Performance

The braking system is one of the most important components of a vehicle. In general, the brakes will generate heat due to the braking process. The heat generated must be released into the environment to maintain braking performance at optimal conditions. In extreme conditions, braking will fail. The braking system can be developed as a braking support system is a non-contact braking system. One form of the non-contact braking system is the eddy current brake (ECB). ECB is an electric braking system with the principle of eddy current. In the ECB, overheating will result in decreased performance. The approach that can be taken to determine braking performance during heat generation is the modeling process using FEM. This study uses FEM to analyze the heat generated during braking. In addition to using FEM, research was carried out using experiments as a comparison. Analysis of heat generation in braking is needed to determine whether braking with ECB can be a backup and its potential as a substitute for friction brakes. The results show that the ECB heat generation event that affects the temperature rise reduces the braking torque performance. Research indicates that when overheating occurs, braking performance will decrease by up to 10% when the disk surface temperature rises more than 20 °C. It shows the importance of managing heat that occurs in the ECB.

Brake Power and Load Analysis of Electromagnetic Braking System

This study aimed to develop a model and prototype of a more sustainable electromagnetic braking system which can cope with the future demands of the automobile industry due to the increasing number of e-vehicles. The braking mechanism is been used in almost every type of mechanical vehicle and it utilizes crude oil as fuel which when burnt causes air pollution. To save the environment from air pollution e-vehicles have been introduced to the market. Electromagnetic brakes are been used in e-vehicles as these vehicles incorporate huge electric systems which may be damaged or ignited through any leakage from the hydraulic brake. In this study, engineering knowledge has been implemented to design and fabricate a model of the electromagnetic braking system (EMS) which works on the principle of eddy current. A 3D model of EMS was developed. Further, static displacement and brake power analyses were performed to check the strength of EMS and the performance of the prototype developed, respectively. At an average speed of 31 RPM, brake power produced was 3.9 W. Static structural analysis on a frame made of grey cast iron showed that there was negligible deformation for load up to 200 N. Electromagnetic braking system based on this analysis and model could meet the market needs for conveyor belt application as well. The observations from this study might be useful in the development of a more efficient electrical vehicle braking system with varying demands of momentum.

Energy Storage for High Speed Trains: Economical and Energy Saving Evaluation

Increasing the utilization rate of regenerative braking energy in rail systems is one of the ongoing applications increasing in significance in recent years. In rail systems, braking is made with two ways, mechanical and electrical. While the energy released due to mechanical braking cannot be recovered, the energy released due to electrical braking can be reused as regenerative braking energy. This regenerative braking energy varies according to the dynamics of the system and it can be given back to the grid, stored in storage devices or burned in resistors (it is not desired). This study develops a novelty algorithm within the scope of this objective and provides the calculation of the regenerative braking energy recovery rate and then making a decision for storage or back to grid of this energy. Afterwards, the regenerative braking energy was calculated with the help of this algorithm for Eskisehir-Ankara and Ankara-Eskisehir trips in two different passengers (load) scenarios, using the YHT 65000 high-speed train, which was chosen as a case study. Then, with a decision maker added to this classical regenerative braking energy algorithm, it will be decided whether this energy will be stored or forward back into the grid for the purpose of providing non-harmonic energy to the grid.

Surrogate role of machine learning in motor-drive optimization for more-electric aircraft applications

Motor drives form an essential part of the electric compressors, pumps, braking and actuation systems in the More-Electric Aircraft (MEA). In this paper, the application of Machine Learning (ML) in motor-drive design and optimization process is investigated. The general idea of using ML is to train surrogate models for the optimization. This training process is based on sample data collected from detailed simulation or experiment of motor drives. However, the Surrogate Role (SR) of ML may vary for different applications. This paper first introduces the principles of ML and then proposes two SRs (direct mapping approach and correction approach) of the ML in a motor-drive optimization process. Two different cases are given for the method comparison and validation of ML SRs. The first case is using the sample data from experiments to train the ML surrogate models. For the second case, the joint-simulation data is utilized for a multi-objective motor-drive optimization problem. It is found that both surrogate roles of ML can provide a good mapping model for the cases and in the second case, three feasible design schemes of ML are proposed and validated for the two SRs. Regarding the time consumption in optimizaiton, the proposed ML models can give one motor-drive design point up to 0.044 s while it takes more than 1.5 mins for the used simulation-based models.

Prognosis of Wear Progression in Electrical Brakes for Aeronautical Applications

The evolution towards “more electric” aircrafts has seen a decisive push in the last decade, due to the growing environmental concerns and the development of new market segments (flying taxis). Such push interested both the propulsion components and the aircraft systems, with the latter seeing a progressive trend in replacing the traditional solutions based on hydraulic power with electrical or electromechanical devices. Although more attention is usually devised towards the flight control actuation, an interesting and fast-developing application field for electro-mechanical systems is that of the aeronautical brakes. Electro-mechanical brakes, or E-Brakes hereby onwards, would present several advantages over their hydraulic counterparts, mainly related to the avoidance of leakage issues and the simplification of the system architecture. The more difficult heat dissipation, associated with the thermal issues that usually constitute one of the most significant sizing constraints for electromechanical actuators, limits so far, their application (or proposal of application) to light-weight vehicles. Within this context, the development of PHM solutions would align with the need for an on-line monitoring of a relatively unproven component. This paper deals with the preliminary stages of the development of such PHM system for an E-Brake to be employed on a future executive class aircraft, where the brake is actuated through four electro-mechanical actuators. Since literature on fault diagnosis and prognosis for electrical motors is fairly extensive, we focused this preliminary analysis on the development of PHM techniques suitable to monitor and prognose the evolution of the brake pads wear instead. The paper opens detailing the system architecture and continues presenting the high-fidelity dynamic model used to build synthetic data-sets representative of the possible operating conditions faced by the E-Brake within realistic operative scenarios. Such data are then used to foster a preliminary feature selection process, where physics-based indexes are compared and evaluated. Simulated degradation histories are then used to test the application of data-driven fault detection algorithm and the possible application of particle-filtering routines for prognosis.

Trajectory Tracking within a Hierarchical Primitive-Based Learning Approach

A hierarchical learning control framework (HLF) has been validated on two affordable control laboratories: an active temperature control system (ATCS) and an electrical rheostatic braking system (EBS). The proposed HLF is data-driven and model-free, while being applicable on general control tracking tasks which are omnipresent. At the lowermost level, L1, virtual state-feedback control is learned from input–output data, using a recently proposed virtual state-feedback reference tuning (VSFRT) principle. L1 ensures a linear reference model tracking (or matching) and thus, indirect closed-loop control system (CLCS) linearization. On top of L1, an experiment-driven model-free iterative learning control (EDMFILC) is then applied for learning reference input–controlled outputs pairs, coined as primitives. The primitives’ signals at the L2 level encode the CLCS dynamics, which are not explicitly used in the learning phase. Data reusability is applied to derive monotonic and safely guaranteed learning convergence. The learning primitives in the L2 level are finally used in the uppermost and final L3 level, where a decomposition/recomposition operation enables prediction of the optimal reference input assuring optimal tracking of a previously unseen trajectory, without relearning by repetitions, as it was in level L2. Hence, the HLF enables control systems to generalize their tracking behavior to new scenarios by extrapolating their current knowledge base. The proposed HLF framework endows the CLCSs with learning, memorization and generalization features which are specific to intelligent organisms. This may be considered as an advancement towards intelligent, generalizable and adaptive control systems.

Application of regenerative braking on electric rolling stock

This article provides an overview of ways to improve the efficiency of regenerative braking on electric rolling stock. The advantages and disadvantages of this type of braking are considered. The requirements for the electric braking system are listed. Some analysis of the work of JSC Russian Railways on the implementation of the Energy Saving and Energy Efficiency Program is presented.

Regenerative Braking System: A Review

Abstract: Electric cars square measure associate interest within the market. Today, existing braking technologies are used. This braking technology consumes tons of energy throughout braking within the style of heat. Therefore, regenerative braking is that the most significant methodology of focusing as a result of it's associate energy saving methodology. Increase the potency of electrical vehicles by reducing waste of energy. In electrical vehicle regenerative braking mode, the K.E. of the wheels is bornagain into electricity and keep within the battery or electrical condenser. This methodology has been improved mistreatment flywheels, DC-DC converters. Once a quick moving vehicle is applied a brake the momentum energy is wasted. The brake energy converter could be a compact system mounted in cylinder that absorbs this power and converts it to electricity that may be keep in battery for more use. Compact, efficient, low value and recycles energy nicely, prevents wastage. This method fits within the vacant house of the drum brakes of auto as a result of currently day's disk brakes square measure used. Low weight, compact size and power is made altogether four wheels of the vehicle. Straightforward construction, low value and straightforward to use. Absorbs brake power that the load on the hydraulic brakes is reduced thus less wear of brakes. Motor is within the earlier models with a centralized battery unit, system power to weight magnitude relation is extremely low, i.e., low power is made as compared to the burden of the system. Braking potency is low and tends to explosive brake in emergency conditions. Keywords: Energy, Brake, Electricity, Flywheel, Vehicle.