A computer model for the performance simulation of vehicles equipped with traction drive continuously variable transmission （CVT） is presented. The model integrates the traction drive CVT subsystem into an existing ...A computer model for the performance simulation of vehicles equipped with traction drive continuously variable transmission （CVT） is presented. The model integrates the traction drive CVT subsystem into an existing overall vehicle system. The characteristics of engine output torque are formulated using neural networks, and torque converter is modeled using lookup tables. Component inputs and outputs are coupled in the dynamic equations and interfaces in the powertrain system. The model simulation can provide evaluation of vehicle performance in drivability, fuel economy and emission levels for various drive ranges prior to the prototyping of the vehicle. As a design tool, the model assists engineers in understanding the effect ofpowertrain components on vehicle performance and making decisions in the selection of key design parameters. The model is implemented in the MATLAB/Simulink environment. The performance simulation of a test vehicle is included as a numerical example to illustrate the effectiveness of the model.展开更多
The traction drive system is the“heart”of rail transit vehicles.The development of sustainable,secure,economic,reliable,efficient,and comfortable contemporary rail transportation has led to increasingly stringent re...The traction drive system is the“heart”of rail transit vehicles.The development of sustainable,secure,economic,reliable,efficient,and comfortable contemporary rail transportation has led to increasingly stringent requirements for traction drive systems.The interest in such systems is constantly growing,supported by advancements such as permanent magnet(PM)motors,advanced electronic devices such as those using silicon carbide(SiC),new-generation insulating materials such as organic silicon,and advanced magnetic materials such as rare-earth magnets and amorphous materials.Progress has also been made in control methods,manufacturing technology,artificial intelligence(AI),and other advanced technologies.In this paper,we briefly review the state-of-the-art critical global trends in rail transit traction drive technology in recent years.Potential areas for research and the main obstacles hindering the development of the next-generation rail transit traction drive systems are also discussed.Finally,we describe some advanced traction drive technologies used in actual engineering applications.展开更多
The move from internal combustion engine vehicles to electric vehicles is happening rapidly,which demands a stepwise change in priorities for the vehicle design process with rational consideration of emerging technolo...The move from internal combustion engine vehicles to electric vehicles is happening rapidly,which demands a stepwise change in priorities for the vehicle design process with rational consideration of emerging technologies.This paper focuses on the efficiency of a particular form of high fixed-ratio(15:1)traction drive speed reducer.This is suitable for use in conjunction with a high-speed electric motor for automotive applications.A general discussion of the characteristics of other fixed-ratio traction drives is provided followed by an analysis of underlying efficiency issues.The paper presents details of the speed reducer prototype called a"Silk Drive"and the vehicle for which it was designed.Data from laboratory testing of the prototype are presented,and an efficiency map for the transmission is developed.The efficiency map and vehicle parameters are used in a simulation to determine the overall transmission efficiency for the world harmonized light vehicles test cycles(WLTC)class 3b drive cycle.The importance of transmission efficiency at low power levels,in specific input speed and torque regions,is demonstrated using a novel method for identifying those speed torque regions that most strongly affect overall efficiency.The method applies to all drivetrain components and pinpoints those regions that need to be the focus in the optimal design of such components.This paper presents evidence that the efficiency of zero-spin,fixed-ratio traction drives is similar to that of conventional gear drives.展开更多
Through its new technology the ISCAD system provides up to 300 kW with a safe-to-touch 48 Volt battery.This results in a high-performance drive that is intrinsically electrically safe.The novel machine design requires...Through its new technology the ISCAD system provides up to 300 kW with a safe-to-touch 48 Volt battery.This results in a high-performance drive that is intrinsically electrically safe.The novel machine design requires new concepts for power electronics,control systems,and integration strategies.Further degrees of freedom yield to challenges and even more important to possibilities for all kinds of applications.The innovation of the design will be explained and adjustments for power electronics and control will be worked out.The focus of this paper is the 3rd generation of Intelligent Stator Cage Drive(ISCAD)prototypes.This first integrated and compact prototype has been used to re-equip a Geely Emgrand EV.The entire system and the mentioned process are described in detail.In addition,the in-house designed 48 V battery is highlighted.Simulations and measurements give an overall demonstration of the potential and the current status of the drive.展开更多
A five leg inverter (FLI) control is incorporated to drive two independent rated permanent magnet synchronous motors (PMSMs) for automotive applications. Literature evidences many attempts of employing the FLI for con...A five leg inverter (FLI) control is incorporated to drive two independent rated permanent magnet synchronous motors (PMSMs) for automotive applications. Literature evidences many attempts of employing the FLI for controlling two general purpose/special motors, where variety of modulation techniques has been practiced for performance enhancement. Also in these cases one leg of inverter is common to both the motors. The expanded two arm modulation (ETAM) has been generally engaged in FLI. In ETAM the percentage voltage utilization factor (VUF) is calculated based on “α<sub>max</sub>”, where “α<sub>max</sub>” is the maximum modulation index and equal to and hence it restricts the VUF to 50%. This makes the FLI drives to use the dc link in inefficient way, which is due to the fact that conventional ETAM works with voltage reference. This paper modifies the ETAM in an ingenious way to improve the VUF further through current reference. In addition, the developed current reference expanded two arm modulation (CRETAM) minimizes the current harmonics and torque ripple as well. A detailed comparison of the CRETAM with the conventional ETAM and the competent digital counterpart, space vector pulse width modulation (SVPWM), is also presented. The enhancement in VUF, torque ripple minimization and current total harmonic distortion (THD) reduction are found in the MATLAB based simulation results.展开更多
基金This project is supported by University Research Program of Ford MotorCompany and Visiting Scholar Program of State Key Laboratory on Me-chanical Transmission of Chongqing University, China.
文摘A computer model for the performance simulation of vehicles equipped with traction drive continuously variable transmission （CVT） is presented. The model integrates the traction drive CVT subsystem into an existing overall vehicle system. The characteristics of engine output torque are formulated using neural networks, and torque converter is modeled using lookup tables. Component inputs and outputs are coupled in the dynamic equations and interfaces in the powertrain system. The model simulation can provide evaluation of vehicle performance in drivability, fuel economy and emission levels for various drive ranges prior to the prototyping of the vehicle. As a design tool, the model assists engineers in understanding the effect ofpowertrain components on vehicle performance and making decisions in the selection of key design parameters. The model is implemented in the MATLAB/Simulink environment. The performance simulation of a test vehicle is included as a numerical example to illustrate the effectiveness of the model.
基金supported by the National Key Research and Development Program of China(No.2018YFB1201804)the Science and Technology Research and Development Plan of China State Railway Group Co.,Ltd.(No.N2021J049).
文摘The traction drive system is the“heart”of rail transit vehicles.The development of sustainable,secure,economic,reliable,efficient,and comfortable contemporary rail transportation has led to increasingly stringent requirements for traction drive systems.The interest in such systems is constantly growing,supported by advancements such as permanent magnet(PM)motors,advanced electronic devices such as those using silicon carbide(SiC),new-generation insulating materials such as organic silicon,and advanced magnetic materials such as rare-earth magnets and amorphous materials.Progress has also been made in control methods,manufacturing technology,artificial intelligence(AI),and other advanced technologies.In this paper,we briefly review the state-of-the-art critical global trends in rail transit traction drive technology in recent years.Potential areas for research and the main obstacles hindering the development of the next-generation rail transit traction drive systems are also discussed.Finally,we describe some advanced traction drive technologies used in actual engineering applications.
文摘The move from internal combustion engine vehicles to electric vehicles is happening rapidly,which demands a stepwise change in priorities for the vehicle design process with rational consideration of emerging technologies.This paper focuses on the efficiency of a particular form of high fixed-ratio(15:1)traction drive speed reducer.This is suitable for use in conjunction with a high-speed electric motor for automotive applications.A general discussion of the characteristics of other fixed-ratio traction drives is provided followed by an analysis of underlying efficiency issues.The paper presents details of the speed reducer prototype called a"Silk Drive"and the vehicle for which it was designed.Data from laboratory testing of the prototype are presented,and an efficiency map for the transmission is developed.The efficiency map and vehicle parameters are used in a simulation to determine the overall transmission efficiency for the world harmonized light vehicles test cycles(WLTC)class 3b drive cycle.The importance of transmission efficiency at low power levels,in specific input speed and torque regions,is demonstrated using a novel method for identifying those speed torque regions that most strongly affect overall efficiency.The method applies to all drivetrain components and pinpoints those regions that need to be the focus in the optimal design of such components.This paper presents evidence that the efficiency of zero-spin,fixed-ratio traction drives is similar to that of conventional gear drives.
文摘Through its new technology the ISCAD system provides up to 300 kW with a safe-to-touch 48 Volt battery.This results in a high-performance drive that is intrinsically electrically safe.The novel machine design requires new concepts for power electronics,control systems,and integration strategies.Further degrees of freedom yield to challenges and even more important to possibilities for all kinds of applications.The innovation of the design will be explained and adjustments for power electronics and control will be worked out.The focus of this paper is the 3rd generation of Intelligent Stator Cage Drive(ISCAD)prototypes.This first integrated and compact prototype has been used to re-equip a Geely Emgrand EV.The entire system and the mentioned process are described in detail.In addition,the in-house designed 48 V battery is highlighted.Simulations and measurements give an overall demonstration of the potential and the current status of the drive.
文摘A five leg inverter (FLI) control is incorporated to drive two independent rated permanent magnet synchronous motors (PMSMs) for automotive applications. Literature evidences many attempts of employing the FLI for controlling two general purpose/special motors, where variety of modulation techniques has been practiced for performance enhancement. Also in these cases one leg of inverter is common to both the motors. The expanded two arm modulation (ETAM) has been generally engaged in FLI. In ETAM the percentage voltage utilization factor (VUF) is calculated based on “α<sub>max</sub>”, where “α<sub>max</sub>” is the maximum modulation index and equal to and hence it restricts the VUF to 50%. This makes the FLI drives to use the dc link in inefficient way, which is due to the fact that conventional ETAM works with voltage reference. This paper modifies the ETAM in an ingenious way to improve the VUF further through current reference. In addition, the developed current reference expanded two arm modulation (CRETAM) minimizes the current harmonics and torque ripple as well. A detailed comparison of the CRETAM with the conventional ETAM and the competent digital counterpart, space vector pulse width modulation (SVPWM), is also presented. The enhancement in VUF, torque ripple minimization and current total harmonic distortion (THD) reduction are found in the MATLAB based simulation results.
