Motor Traction System Research Articles

IDSN: A one-stage interpretable and differentiable STFT domain adaptation network for traction motor of high-speed trains cross-machine diagnosis

A surge of transfer fault diagnosis techniques has been proposed to guarantee the safe operation of traction motor systems. However, existing efforts highly depend on the availability of fault data in source domain, which is rare in practice due to the regular maintenance. Fortunately, self-customized testbeds provide an opportunity to easily obtain fault data, assuming that the simulated data can be utilized to monitor the real-world traction motor systems via the cross-machine diagnosis method. Besides, current deep learning-based cross-machine fault diagnosis methods suffer from the poor physical interpretability and the troublesome hype-parameter selection. To tackle aforementioned issues, a one-stage Interpretable and Differentiable STFT cross-machine dual-driven adaptation Network (IDSN) is proposed. In IDSN, a new paradigm termed interpretable differentiable STFT layer is devised, where a derivable coefficient is introduced to adjust pivotal parameters of STFT such as window length by the gradient descent. Prominently, it is a plug-and-play module, which can be embedded into the arbitrary typical network without conflict. Besides, a novel adaptive trade-off coefficient is developed to tackle the weight matching of the domain discrepancy metric. Finally, to ensure the reliability and effectiveness of cross-machine diagnosis, a concise yet valid smoothed joint maximum mean discrepancy is proposed, which simultaneously promotes intra-class compactness and inter-class separability. The results of experiments confirm that the proposed IDSN outperforms the state of the art.

Unified Maximum Voltage Utilization Controls for Half-Centralized Open-End Winding Permanent-Magnet Motor Systems

In order to extend the speed range and reduce power electronics devices of the primary permanent-magnet linear motor traction system, a half-centralized open-end winding topology is studied in this article, in which <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">N</i> movers are supplied by <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">N</i> +1 voltage-source inverters. In order to maximize the speed range, two unified maximum voltage utilization control (UMVUC) methods are proposed for the studied traction system, which can be easily implemented for any number of movers. The first UMVUC is named as the original UMVUC, and it requires a heavy computation burden, which makes the implementation difficult when the number of movers is large. For the linear motor system, the relative positions of all movers are approximately constant. Based on this feature, the second UMVUC named as simplified UMVUC is proposed, which can significantly reduce the computation burden. In order to suppress the zero-sequence current (ZSC) and reduce the switching loss, a zero-sequence polarity assignment method is employed in the proposed UMVUCs. An experiment platform is developed, and the effectiveness of the proposed UMVUCs has been validated by experimental results.

Phase Model Predictive Voltage Control for Half-Centralized Open-End Winding Permanent-Magnet Linear Motor Traction Systems

In order to extend the speed range and reduce power electronics devices of the permanent-magnet linear motor traction system, a half-centralized open-end winding topology is studied in this article, in which two movers are supplied by three voltage-source-inverters (VSIs). All these VSIs share a common dc-bus voltage, and the zero-sequence current becomes a challenge. In order to solve cope with this challenge, two phase model predictive voltage controls (PMPVCs) are proposed. Referring to the traditional finite-control-set MPVC (FCS-MPVC), an FCS-PMPVC scheme is proposed and the optimal phase voltage group is determined by minimizing three independent phase cost functions. For FCS-PMPVC, 21 phase voltage group are evaluated while the evaluation number of the traditional FCS-MPVC is 512. In order to reduce the computation burden furthermore, a new concept phase voltage vector (PVV) is defined, and the optimal PVV is directly determined by the nearest distance principle instead of the time-consuming evaluation. The second PMPVC is named as geometrical-location PMPVC (GL-PMPVC). Both PMPVCs have same performances while the computation burden of GL-PMPVC is nearly 47% of that of FCS-PMPVC. The effectiveness of the proposed PMPVCs have been verified by experimental results.

Analysis of lithium-ion thermostabilization systems traction batteries of electric vehicles

Problem. The paper solves an important scientific and practical problem that allows to increase the competitive advantages of agricultural producers through the use of modern energy-efficient tractors with electric transmission. The control system of the traction electric drive is a component of the modern electric tractor of the fourth traction class which has become the most widespread and is intended for providing movement in the modes of various loading. The study of electric motors of a modern electric tractor of the fourth traction class is carried out. The electric motor is characterized by input and output parameters, internal parameters or state parameters, external influences. Methodology. The methods of theoretical basic electrical engineering have been developed in the production and calculation of circuits. Also classical methods of statistics of signals from ADC are used. Results. The technique of processing information from the current, voltage and temperature sensors using a mathematical apparatus without using harmonic analysis is presented. The hardware implementation of the proposed method allows the use of simplified computing tools. Originality. Complex analysis of the data obtained from the current, voltage and temperature sensors is carried out. During the analysis, the range of velocities with stable operation of the measurement system was determined. Based on the data obtained, it is concluded that the use of a horn antenna as a concentrator substantially eliminates lateral interference and extends the range of possible velocity measurements. It is shown that the level of sampling significantly affects the upper limit of the measurement speed. Practical value. It is shown that: As a result of the work, an important scientific and practical problem was solved, which allows to increase the energy efficiency of tractors through the use of tractors of the fourth traction class electric drive. To maintain the maximum energy efficiency of the traction electric drive of the tractor in the modes of various loads, its control system must include means of displaying the current state of the energy parameters of the power plant. The electrical equipment must include an on-board computer, which helps the driver to make the optimal tasks of work, according to preliminary calculations, as well as display the information needed on the route, the state of the vehicle, means of communication. communication of the car with the external environment, with the navigation system, etc. The on-board computer provides information to the touch screen with programmable virtual controls, and communicates with the driver's mobile systems. The study of electric motors of a fifth traction class electric tractor was carried out. As an object of motor control, it is characterized by input and output parameters, internal parameters or state parameters, external influences. An algorithm for selecting the parameters of the traction motor system has been developed and a circuit implementation of the control system has been offered.

Performance analysis of DTC-SVM in a complete traction motor control mechanism for a battery electric vehicle

The transport sector is essential for socio-economic growth; however, the sector contributes a large portion of global carbon dioxide emissions. Consequently, electric vehicles have received increasing attention from various stakeholders in order to provide a solution to the current environmental impact of the transport industry. Current literature on electric vehicle powertrains show that electric vehicles are complex systems, with one of the most essential subsystems being the traction motor control mechanism. As a result, the objective of this paper is to add to the research conducted in the field of electric vehicle powertrains by carrying out comprehensive investigations into the suitability and performance of space vector modulation based direct torque control in the traction motor control system of an electric vehicle with a complete drive system. Initially, a conventional direct torque control mechanism was implemented for control of the traction motor system. The results of the investigation into implementation of conventional direct torque control highlighted the expected issues associated with the mechanism. Implementation of improvements to the conventional direct torque control model, such as the use of a space vector modulation based direct torque control model with closed loop torque control, field-weakening and sensorless control produced significantly favorable results, providing decreased torque and current ripples, operation over a wide speed range, and accurate speed control without the need for mechanical speed sensors. Such results demonstrate that the complete control mechanism investigated is well suited for use in electric vehicle applications.

Phase-Shifting Fault-Tolerant Control of Permanent-Magnet Linear Motors With Single-Phase Current Sensor

In this article, a phase-shifting fault-tolerant control (PS-FTC) method with single-phase current sensor is proposed for primary permanent-magnet linear motor traction system. The phase with healthy sensor is defined as the first phase, while the other two phases without healthy sensors are, respectively, defined as the second and third phases. In PS-FTC, hysteresis current control is adopted. The actual currents of the second and third phases are replaced by the estimated values, while the reference values are obtained by phase shifting of the estimated first-phase current. Although the linear motor parameters have been used in the calculation of the estimated currents, the parameter variations do not affect the performances of PS-FTC. Compared with the conventional fault-tolerant control (C-FTC) method and the existing fault-tolerant control schemes with single-phase current sensor, PS-FTC is robust and shows better steady-state performances. Furthermore, a hybrid strategy combining PS-FTC and C-FTC is adopted to improve the transient-state performances. The effectiveness of PS-FTC and the hybrid strategy are verified by the theoretical analysis and experimental results.

A Comprehensive Review of Advanced Traction Motor Control Techniques Suitable for Electric Vehicle Applications

Transport and vehicular travel are essential for socio-economic growth, as they enable the operation of cities and businesses globally. However, large percentages of the transport sector currently rely on internal combustion engine vehicles, causing an increase in greenhouse gases and air pollution. Electric vehicles provide a promising solution to the issues faced by the transport sector. As a result, optimization of the electric vehicle powertrain is a key area, with the traction motor control mechanism forming a major component of the powertrain. Consequently, this paper aims to review the novel control techniques which have been applied to the traction motor system in electric vehicles. Direct torque control and indirect field oriented control are commonly applied control techniques as they allow for advanced control of the induction and permanent magnet synchronous motors currently used in most of the electric vehicles being produced. In general, various improvements have been made to conventional direct torque control and indirect field oriented control schemes, in order to reduce ripple and improve parameter insensitivity. While efforts are still being carried out in these areas for electric vehicle applications, it was found that there has been a large emphasis placed on powertrain efficiency improvement through optimization of the traction motor control system. Efficiency improvements have recently been achieved through optimal selection of stator flux and DC link voltage values. Research into efficiency improvement is likely to continue as extended vehicle range can be achieved.

Coupled Fault-Tolerant Control of Primary Permanent-Magnet Linear Motor Traction Systems for Subway Applications

In this article, a coupled fault-tolerant control (C-FTC) is proposed for primary permanent-magnet linear motor traction system in subway applications. By coupling the faulty mover with a healthy mover, the proposed C-FTC can achieve continuous operation of the faulty mover, in which one or more current sensors fail. A healthy mover is determined as the reference mover. The switch-states of the reference mover are also applied to its mathematical model. As a result, synchronous currents of the reference mover are also estimated from its mathematical model, and they are treated as the reference currents of the mathematical model of the faulty mover. Hence, the switch-states of the faulty mover can be determined. Therefore, the faulty mover can be controlled without any current sensors. The key of C-FTC is to compensate the parameter variations and the nonlinear effects of the faulty mover drive system with those of a healthy mover drive system, which is the main contribution of this article. Comparing with the conventional current-sensorless control, C-FTC has stronger robustness to the parameter variations and the nonlinear effects. The effectiveness and robustness of the proposed C-FTC are verified by simulation and experimental results.

Dual-Level Located Feedforward Control for Five-Leg Two-Mover Permanent-Magnet Linear Motor Traction Systems

Based on the model predictive current control (MPCC), a dual-level located feedforward control (DLFC) is proposed for the five-leg dual-mover primary permanent-magnet linear motor traction system, in which, two three-phase movers are fed by one five-leg voltage-source inverter (VSI). In the proposed DLFC, the studied traction system is divided into dual-level subsystems, including mover level and system level. In the mover level, it is assumed that one mover is fed by one three-leg VSI. The reference synchronous currents are replaced by the reference static voltages, and the model current predictions are eliminated by the discrete mover voltage vectors (MVVs). Furthermore, the global optimal MVVs are determined by the mover-level geometrical location. If the implementation conflicts between two global optimal MVVs, two local optimal MVVs will be determined by the system-level geometrical location to replace one former global optimal MVV. Compared with MPCC, the computation burden of DLFC can be significantly reduced. If both control methods use the same sampling period, they have the same performances. On the other hand, DLFC can use shorter sampling period, and it can perform better than MPCC. All the theoretical analyses are verified by simulation and experimental results.

Simplified Model Predictive Current Control of Primary Permanent-Magnet Linear Motor Traction Systems for Subway Applications

In this paper, a simplified model predictive current control (MPCC) is proposed for the primary permanent-magnet linear motor traction system in subway applications, which is fed by one two-level voltage-source-inverter (VSI). Based on the deadbeat concept, the reference voltage vector is calculated to eliminate the difference between the measured and reference currents in the next sampling period. Due to the discrete feature of the VSI, the reference voltage vector usually cannot be provided. Hence, the distance of a voltage vector is defined, and the voltage vector with the shortest distance is selected as the optimal one, which is called as the shortest distance principle in this paper. According to the shortest distance principle, the distribution of the reference voltage vector is divided into seven sectors, and the optimal voltage vector can be easily determined considering the location of the reference voltage vector. As a result, the computation cost is significantly reduced. However, the performances of MPCC are not affected by this simplification. The equivalence between the proposed and conventional MPCCs is proved in theory. All the theoretical analyses are verified by experimental results.

The influence of transom pipe gap on the resonance response in motorized bogie and traction motor system

The influence of transom pipe gap on the resonance response in motorized bogie and traction motor system

A New Traction Motor System With Integrated-Gear: A Solution for Off-Road Machinery

Off-road traction applications require extremely high torque, especially, at low speeds. Such a high torque can be reached by gearing up the torque of an electrical machine. A tooth-coil permanent magnet synchronous machine with an integrated planetary gear is proposed as a solution for heavy off- and on-road traction applications. The key benefits of tooth-coil permanent-magnet synchronous machine (PMSM) in the proposed drive system and its integration with a planetary gearbox are explained in detail. A multi-objective optimization is performed to determine the slot/pole combination of the PMSM and the design process of the proposed drive system is entirely clarified. The proposed tooth-coil PMSM is investigated by electromagnetic and structural finite element analysis to obtain the final design and highlight the machine performance. A prototype is built to validate the proposed system. The results show that the traction drive system works well in laboratory and offers means to serve as a traction system in heavy off- and on-road applications.

Study on the optimization of linear induction motor traction system for fast-speed maglev train

Background: The short stator linear induction motor (LIM) is normally used in medium-low speed maglev train.&#x0D; The restriction by mounting space on bogie and motor input voltage from the third power supply rail lead that the maximum speed of medium-low speed maglev train can reach no more than 120 km/h.&#x0D; Aim: In this paper, by means of the LIM design optimization, improvement of the LIM force characteristic in high speed range, the maximum speed of medium-low speed maglev train can reach 160 km/h.&#x0D; Methods: After comparing the LIM theoretical calculation and actual test data, it shows that the new designed LIM is effective.&#x0D; Conclusion: Afterwards, by installing the new designed LIMs, the traditional medium-low speed maglev train becomes a fast-speed maglev train, and it has a bright future in transportation applications.

Progress review of US-China joint research on advanced technologies for plug-in electric vehicles

The United States and China are the world’s largest automobile markets and oil consumers, and both face a severe challenge to conserve energy and reduce tailpipe emissions. Thus, both countries urgently need to transform conventional internal combustion engines to electrified powertrains. Targeting the advanced core technologies of plug-in electric vehicles (PEVs), a joint research collaboration between China and the US, called the “Clean Vehicle Consortium” (CVC), was set up in 2010. Six years of collaboration on PEV technologies has resulted in significant progress in three technical areas. Based on CVC publications, we review herein the progress made by the CVC research efforts on three key advanced PEV technologies. This includes the development of a safe battery with an energy density of 260 W h kg−1 and a systematic method for designing safe traction battery systems. Thus, a breakthrough in high power density and efficient traction motor systems has occurred. In addition to discussing advanced electric-drive powertrains, we also discuss global energy management strategies that aim to improve PEV energy efficiency. This discussion covers scientific and comprehensive analysis methods to analyze energy systems, which include cost-benefit analyses of plug-in hybrid electric vehicles, life-cycle assessments for evaluating vehicle emissions, and PEV-ownership projections.

Modelling of a Multi Motors Traction System Connected in Series Using a Matrix Converter

The first generation of multi-machine systems is limited on two .the first configuration consists of a continuous floor which feeds several three-phase inverters connected in parallel, or each inverter supplies a three-phase machine .the control of each machine is independent via its inverter and its algorithm control .the second configuration consists of a single inverter, which also feeds in parallel three phase machines .for this structure, the machines must have the same speed and suffer the same torque load .these two conditions make the use of this system in a limited scope .It is impossible to connect in series several three-phase machines powered by a single-phase power converter and that each machine in the group have an independent speed control .but, the use of multi-phase converters associated with polyphase machine . generate additional degrees of freedom .With these, several polyphase machines can be connected in series in an appropriate transposition phases. The objective of this work is to order, model and characterize the behavior of a training system multimachines composed of two five phase synchronous permanent magnet motors connected in series and powered by a five phase matrix converter applied to the rail traction.

Control simulation of PMSM traction system of high speed train when passing neutral section

Purpose – In electric system of high-speed trains, neutral sections are set to balance the three-phase load. When passing neutral sections, the train should detach from the power supply for a short time. To permanent magnet synchronous motors (PMSMs) traction system, the voltage of DC link will increase quickly due to the back-EMF of PMSM during this time. Although the energy consumption braking method can be adopted to consume the feedback energy. It not only wastes energy, but also causes more speed drop of the train. The paper aims to discuss these issues. Design/methodology/approach – In order to get better performance when the train is under passing neutral section condition, a suitable control method is proposed, in which the torque command is set to zero and d-axis current order remains unchanged during passing neutral section. Based on a co-simulation model, the influences of this method on the PMSMs traction system are compared with that of traditional method, which is used in induction motors traction system. This model combines both control strategy and finite element model of motor, which can take the effects of magnetic saturation and power loss into consideration. Findings – In PMSMs traction system, PMSMs work as generators during neutral section, and charge to DC bus, which may cause over-voltage damage. Moreover, there would be strong torque shock at the moment of power cut-off. It is finally found that, with the suitable control method, the high-speed train can pass the neutral section with less speed drop, less torque shock and little DC link voltage rise. Originality/value – The control method proposed in this paper is easier to achieve and gets a better performance of PMSMs traction system in high-speed train compared with the traditional method. Furthermore, the co-simulation model is much closer to reality than the analytical model.

直流電気鉄道車両におけるベクトル制御された誘導電動機駆動システムのダンピング制御系設計法

直流電気鉄道車両におけるベクトル制御された誘導電動機駆動システムのダンピング制御系設計法

PMSM의 제동력 확보에 의한 회생제동 제어에 관한 연구

In this paper, a blind spot of motor car, and the put case that is driven the miniature model motor system, when make practical application of the permanent magnet synchronous motors(PMSM) braking and having had the ability that can all absorb regenerative power by means of electric brake which is occurred. a tow system of a miniature model motor traction system is established by 1C1M methods to control individually permanent magnet synchronous motors (PMSM) of each motor. vector control method is applied in order to improve ride quality of motor car and the efficient use of energy. it was obtained excellent experiment results from the simulations as a function of momentum load and miniature model. Also, this study is investigated the regenerative braking power securities of permanent magnet synchronous motors, speed detection to stop electric brake at extremely very low speed and motor control method of algorithm.

Experimental Study on a Voltage Source Inverter-fed Induction Motor Traction System Connected to Fuel Cell

This paper describes the experimental results of a test to drive two induction motors through a VVVF inverter by 25kW class proton membrane type fuel cells (PEMFCs). The experiments are aimed at verifying the compatibility between the drive system for the railway vehicle traction and FCs. This paper describes test results of powering, powering-off procedure, and simulated slip-readhesion control test, respectively. Through the experiments, we obtained useful knowledge required in designing the fuel cell drive system.

Development of Wheel Mounted Direct Drive Traction Motor for Rail Vehicle

In the conventional rail vehicle, traction motor is mounted on the truck frame, and the shaft torque is transmitted to the wheel set via flexible coupling and reduction gearing. The reduction gearing is effective to increase the torque, but gives rise to maintenance, noise and transmission loss. To overcome these problems and simplify the truck structure, we conceived an idea of wheel mounted direct drive traction motor system without the reduction gearing, and started the development.In this system, the traction motor is required to produce more torque and reduce the mass. So we introduced permanent magnet synchronous motor for the first time in the rail vehicle. Here, we propose fundamental structures of the wheel mounted direct drive traction motors, and present a prototype wheel mounted traction motor model, which is manufactured by trial as the first step of the development. We overcame the problem of temperature rise of permanent magnet, through analysis and improvement of the magnetic structure.