Mode switching control strategy of dual motors coupled driving on electric vehicles

Based on analyzing the structure and working principle on electric vehicles （EVs） with dual motors coupled by planetarY gears, the control strategy of mode switching was proposed. The power interruption problem on EVs with automatic mechanical transmission （AMT） shifting was resolved. Based on the speed-torque characteristics of the planetary gears and the principle of the auxiliary motor＇ s zero speed braking, control features of mode switching were introduced. The mode shifting between the main motor mode and dual motors coupled driving were studied. Matlab/Simulink was adopted as a platform to develop the simulation model of EVs with dual motors drive system and 3 gears AMT. Simulation results demonstrated that the power interruption of dual motors drive system was solved during mode switching. The power requirements of EVs were satisfied, too.

Torque Distribution of Electric Vehicle with Four In-Wheel Motors Based on Road Adhesion Margin

With the worsening of energy crisis and environmental pollution,electric vehicles with four in?wheel motors have been paid more and more attention. The main research subject is how to reasonably distribute the driving torque of each wheel. Considering the longitudinal motion,lateral motion,yaw movement and rotation of the four wheels,the tire model and the seven DOF dynamic model of the vehicle are established in this paper. Then,the torque distribution method is proposed based on road adhesion margin,which can be divided into anti ? slip control layer and torque distribution layer. The anti?slip control layer is built based on sliding mode variable structure control,whose main function is to avoid the excessive slip of wheels caused by road conditions. The torque distribution layer is responsible for selecting the torque distribution method based on road adhesion margin. The simulation results show that the proposed torque distribution method can ensure the vehicle quickly adapt to current road adhesion conditions,and improve the handling stability and dynamic performance of the vehicle in the driving process.

Stochastic sampled-data multi-objective control of active suspension systems for in-wheel motor driven electric vehicles

This paper addresses the sampled-data multi-objective active suspension control problem for an in-wheel motor driven electric vehicle subject to stochastic sampling periods and asynchronous premise variables.The focus is placed on the scenario that the dynamical state of the half-vehicle active suspension system is transmitted over an in-vehicle controller area network that only permits the transmission of sampled data packets.For this purpose,a stochastic sampling mechanism is developed such that the sampling periods can randomly switch among different values with certain mathematical probabilities.Then,an asynchronous fuzzy sampled-data controller,featuring distinct premise variables from the active suspension system,is constructed to eliminate the stringent requirement that the sampled-data controller has to share the same grades of membership.Furthermore,novel criteria for both stability analysis and controller design are derived in order to guarantee that the resultant closed-loop active suspension system is stochastically stable with simultaneous𝐻2 and𝐻∞performance requirements.Finally,the effectiveness of the proposed stochastic sampled-data multi-objective control method is verified via several numerical cases studies in both time domain and frequency domain under various road disturbance profiles.

Speed Regulation Method Using Genetic Algorithm for Dual Three-phase Permanent Magnet Synchronous Motors

Dual three-phase Permanent Magnet Synchronous Motor(DTP-PMSM)is a nonlinear,strongly coupled,high-order multivariable system.In today’s application scenarios,it is difficult for traditional PI controllers to meet the requirements of fast response,high accuracy and good robustness.In order to improve the performance of DTP-PMSM speed regulation system,a control strategy of PI controller based on genetic algorithm is proposed.Firstly,the basic mathematical model of DTP-PMSM is established,and the PI parameters of DTP-PMSM speed regulation system are optimized by genetic algorithm,and the modeling and simulation experiments of DTP-PMSM control system are carried out by MATLAB/SIMULINK.The simulation results show that,compared with the traditional PI control,the proposed algorithm significantly improves the performance of the control system,and the speed output overshoot of the GA-PI speed control system is smaller.The anti-interference ability is stronger,and the torque and double three-phase current output fluctuations are smaller.

Decentralized Dynamic Event-Triggered Communication and Active Suspension Control of In-Wheel Motor Driven Electric Vehicles with Dynamic Damping

This paper addresses the co-design problem of decentralized dynamic event-triggered communication and active suspension control for an in-wheel motor driven electric vehicle equipped with a dynamic damper. The main objective is to simultaneously improve the desired suspension performance caused by various road disturbances and alleviate the network resource utilization for the concerned in-vehicle networked suspension system. First, a T-S fuzzy active suspension model of an electric vehicle under dynamic damping is established. Second,a novel decentralized dynamic event-triggered communication mechanism is developed to regulate each sensor's data transmissions such that sampled data packets on each sensor are scheduled in an independent manner. In contrast to the traditional static triggering mechanisms, a key feature of the proposed mechanism is that the threshold parameter in the event trigger is adjusted adaptively over time to reduce the network resources occupancy. Third, co-design criteria for the desired event-triggered fuzzy controller and dynamic triggering mechanisms are derived. Finally, comprehensive comparative simulation studies of a 3-degrees-of-freedom quarter suspension model are provided under both bump road disturbance and ISO-2631 classified random road disturbance to validate the effectiveness of the proposed co-design approach. It is shown that ride comfort can be greatly improved in either road disturbance case and the suspension deflection, dynamic tyre load and actuator control input are all kept below the prescribed maximum allowable limits, while simultaneously maintaining desirable communication efficiency.

Principle and Experimental Verification of Novel Dual Driving Face Rotary Ultrasonic Motor

Existing rotary ultrasonic motors operating in extreme environments cannot meet the requirements of good environmental adaptability and compact structure at same time,and existing ultrasonic motors with Langevin transducers show better environmental adaptability,but size of these motors are usually big due to the radial arrangement of the Langevin transducers.A novel dual driving face rotary ultrasonic motor is proposed,and its working principle is experimentally verified.The working principle of the novel ultrasonic motor is firstly proposed.The 5th in-plane flexural vibration travelling wave,excited by the Langevin transducers around the stator ring,is used to drive the rotors.Then the finite element method is used in the determination of dimensions of the prototype motor,and the confirmation of its working principle.After that,a laser Doppler vibrometer system is used for measuring the resonance frequency and vibration amplitude of the stator.At last,output characteristics of the prototype motor are measured,environmental adaptability is tested and performance for driving a metal ball is also investigated.At room temperature and 200 V(zero to peak) driving voltage,the motor’s no-load speed is 80 r/min,the stalling torque is 0.35 N·m and the maximum output power is 0.85 W.The response time of this motor is 0.96 ms at the room temperature,and it decreases or increases little in cold environment.A metal ball driven by the motor can rotate at 210 r/min with the driving voltage 300 V(zero to peak).Results indicate that the prototype motor has a large output torque and good environmental adaptability.A rotary ultrasonic motor owning compact structure and good environmental adaptability is proposed,and lays the foundations of ultrasonic motors’ applications in extreme environments.

Genetic algorithm and particle swarm optimization tuned fuzzy PID controller on direct torque control of dual star induction motor

This study presents analysis, control and comparison of three hybrid approaches for the direct torque control (DTC) of the dual star induction motor (DSIM) drive. Its objective consists of combining three different heuristic optimization techniques including PID-PSO, Fuzzy-PSO and GA-PSO to improve the DSIM speed controlled loop behavior. The GA and PSO algorithms are developed and implemented into MATLAB. As a result, fuzzy-PSO is the most appropriate scheme. The main performance of fuzzy-PSO is reducing high torque ripples, improving rise time and avoiding disturbances that affect the drive performance.

Driving force coordinated control of an 8x8 in-wheel motor drive vehicle with tire-road friction coefficient identification

Because of the complexities of tire-road interaction,the wheels of a multi-wheel distributed electricdrive vehicle can easily slip under certain working conditions.As wheel slip affects the dynamic per-formance and stability of the vehicle,it is crucial to control it and coordinate the driving force.With this aim,this paper presents a driving force coordination control strategy with road identification for eight-wheeled electric vehicles equipped with an in-wheel motor for each wheel.In the proposed control strategy,the road identification module estimates tire-road forces using an unscented Kalman filter al-gorithm and recognizes the road adhesion coefficient by employing the recursive least-square method According to road identification,the optimal sip ratio under the current driving condition is obtainedand a controller based on sliding mode control with a conditional integrator uses this value for accel-eration slip regulation.The anti-slip controller obtains the adjusting torque,which is integrated with the driver-command-based feedforward control torque to implement driving force coordination control.The results of hardware-in-loop simulation show that this control strategy can accurately estimate tire-roadrces as well as the friction coefficient,and thus,can effectively fulfill the purpose of driving force coordinated control under different driving conditions.

Electromagnetic analysis and design of in-wheel motor of micro-electric vehicle based on Maxwell

To obtain a good drivability and high efficiency of the micro-electric vehicle, a new driving in-wheel motor design was analyzed and optimized. Maxwell software was used to build finite element simulation model of the driving in-wheel motor. The basic features and starting process were analyzed by field-circuit coupled finite element method. The internal complicated magnetic field distribution and dynamic performance simulation were obtained in different positions. No-load and load characteristics of the driving in-wheel motor was simulated, and the power consumption of materials was computed. The conformity of the final simulation results with the experimental data indicates that this method can be used to provide a theoretical basis to make further optimal design of this new driving in-wheel motor and its control system, so as to improve the starting torque and reduce torque ripple of the motor. This method can shorten the development cycle of in-wheel motors and save development costs, which has a wide range of engineering application value.

Sensorless Vector Control of Parallel-Connected Multiple Induction Motors Fed by a Single Inverter

A method of improving the stability of multiple-motor drive system fed by a 3-leg single inverter has been devised that employs the averages and differences of estimated parameters for field-oriented control. The parameters of each motor (stator current, rotor flux, and speed) are estimated using adaptive rotor flux observers to achieve sensorless control. The validity and effective of the proposed method have been demonstrated through simulations and experiments.

Open Winding-permanent Magnet/Magnet Reluctance Hybrid Rotor Double Stator Synchronous Motor SVPWM Control

Coal mine conveyor belt and other low-speed large torque system,the torque density and torque stability of the motor requirements are higher,permanent magnet/magnet reluctance hybrid rotor double stator synchronous motor(PM/MRHRDSSM)is just adapted to this requirement,however,the traditional close winding single inverter vector control system control PM/MRHRDSSM provides large torque ripple,high speed fluctuation and large total harmonic distortion(THD)of the current,difficult to be used in actual production and life,this paper proposes a large torque open winding-permanent magnet/magnet reluctance hybrid rotor double stator synchronous motor(OW-PM/MRHRDSSM)based on SVPWM dual inverter control strategy,and analysis of open winding double inverter structure,and its voltage vector mathematical model,using the existing two-level inverter as a basis,the bilateral inverter separately discussed its role and control method,as well as the decomposition method of synthetic voltage vector and the inverter device in the small sector on-time,the end of this paper through simulation to compare the traditional close winding single inverter vector control system control PM/MRHRDSSM and the large torque OW-PM/MRHRDSSM based on SVPWM dual inverter control strategy to prove the effectiveness of the proposed method in reducing torque ripple,speed fluctuation and THD of current during motor operation.

Simplified Model Predictive Current Control for Dual Three-phase PMSM with Low Computation Burden and Switching Frequency

Finite-control-set model predictive control(FCSMPC)has advantages of multi-objective optimization and easy implementation.To reduce the computational burden and switching frequency,this article proposed a simplified MPC for dual three-phase permanent magnet synchronous motor(DTPPMSM).The novelty of this method is the decomposition of prediction function and the switching optimization algorithm.Based on the decomposition of prediction function,the current increment vector is obtained,which is employed to select the optimal voltage vector and calculate the duty cycle.Then,the computation burden can be reduced and the current tracking performance can be maintained.Additionally,the switching optimization algorithm was proposed to optimize the voltage vector action sequence,which results in lower switching frequency.Hence,this control strategy can not only reduce the computation burden and switching frequency,but also maintain the steady-state and dynamic performance.The simulation and experimental results are presented to verify the feasibility of the proposed strategy.

基于粒子群算法的纯电动商用车转矩分配策略

针对纯电动商用车采用双电动机驱动时存在的转矩分配问题,提出基于粒子群算法的模糊控制策略.首先在Simulink/Stateflow软件中搭建整车动力系统物理模型,以粒子群算法为基础,进行整车转矩分配.由于计算量大,无法运用于实车,故根据粒子群算法的结果,结合传统项目经验,设计一个参数实时调节模糊控制器来进行转矩分配.该方法运行速度快,且基本达到粒子群全局优化的效果.验证与分析结果表明:与原车单电动机动力系统相比,采用该方法的双电动机动力系统能量消耗减少了12.08%;在双电动机动力系统下,该方法与平均分配控制策略相比,电动机总能量损失降低了13.09%.

基于矢量分类的NPC型三电平双三相PMSM的改进模型预测电压控制

多电平多相电机驱动系统存在电压矢量数目多、冗余复杂及多目标非线性约束等问题。以二极管钳位型三电平六相逆变器驱动双三相永磁同步电机为研究对象,以电机谐波电流抑制和逆变器直流侧中点电位平衡控制为目标,提出一种基于电压矢量三角区域分类的改进模型预测电压控制策略。首先,以基波子平面大投影幅值为原则,对729个电压矢量进行初筛;接着,基于三角区域分类方法对筛选后的电压矢量进行分类,并对期望电压进行所属三角区域定位、确定候选矢量。设计满足电机定子电流谐波抑制及逆变器中点电位平衡控制的目标函数;根据电机数学模型和逆变器特征研究多目标控制权重因子的理论设计方法。不同工况下的有效性及对比实验表明,所研究的控制策略不仅能改善多电平多相电机驱动系统的多目标控制性能,还能有效降低控制器计算负担。

适用于超声电机驱动器的双H桥电路设计

超声电机作为新型电机,其电机驱动器的设计至关重要。基于0.18μm高压CMOS工艺设计了一款适用于超声电机驱动器的双H桥集成电路,本集成电路包含两个相同的独立裸芯,搭配简单的外围电路能够实现两路不同相位电压的输出。同时,内部集成了逻辑控制模块可兼容TTL、CMOS两种输入电平,集成自适应死区控制可避免同一桥臂直通。最后,通过验证板实测可满足100 kHz的两路不同相位电压的输出,可完成对超声电机的有效驱动。

双永磁同步电机自适应抗负载扰动交叉耦合稳定控制策略

双永磁同步电驱系统广泛应用于高精度位置同步传动。针对现有独立控制策略下负载扰动易造成位置同步性能下降的问题,提出交叉耦合控制的双永磁同步电驱系统自适应参数整定优化策略。首先,基于传递函数方法,分析交叉耦合结构作用于单电机不同位置控制的稳定性和带宽,提出兼顾稳定性和抗扰能力的基于电流环交叉耦合的双永磁同步电机比例积分微分(proportional-integral-derivative,PID)位置同步控制结构。其次,基于频域分析传递函数,理论上获取PID控制器参数与双电驱系统稳定性和抗扰能力之间的耦合映射关系,提出表征系统稳定性和抗扰性的等效控制参数,以及抗负载扰动的自适应参数整定方法。最后,搭建双永磁同步电机实验平台,在阶跃和脉动负载工况下与传统PI控制策略作对比实验,结果验证了所提控制策略在不同转速下抵抗不同负载扰动的有效性。

基于眼动追踪技术足踝运动认知双重任务评估系统的信效度研究

目的:探讨基于眼动追踪技术的足踝运动认知双重任务评估系统的可靠性和有效性。方法:采用足踝运动认知双重任务评估系统对健康受试者的眼动和足踝运动功能评测,1周后进行重测,计算组内相关系数(ICC)和进行Bland-Altman分析;用该系统对脑卒中患者进行眼动和足踝运动功能评测,并完成认知和运动功能临床评估,分析评测参数与临床评分的相关性。结果:健康受试者足踝运动认知双重任务测试的重测ICCTMT-A任务=0.509~0.897,ICCTMT-B任务=0.493~0.987。Bland-Altman分析显示,眼动注视次数、眼跳幅度、速度峰个数及平均速度4个主要参数的重测信度均具有较好的一致性。脑卒中患者的效度结果显示,眼动注视次数、注视的空间密度与蒙特利尔认知评估量表(MoCA)评分呈负性相关;足踝运动平均速度与下肢运动功能评分、10米步行平均速度呈正性相关,与计时起立行走-减法计算测试耗时、双任务成本百分比呈负性相关。结论:基于眼动追踪技术的足踝运动认知双重任务评估系统具有良好的信效度,其中眼动注视次数、注视的空间密度是反映认知功能的稳定参数,足踝运动平均速度是反映运动功能和双任务成本的稳定参数。该系统为脑卒中患者足踝运动认知功能评估提供了新技术,有望应用到运动认知功能研究和康复治疗中。

双重任务训练联合渐进性下蹲式抗阻训练在帕金森病患者中应用研究

目的探究双重任务训练联合渐进性下蹲式抗阻训练干预对帕金森病(PD)患者运动功能及平衡能力的影响。方法选取2021年1月至2024年1月江西省九江学院附属医院收治的PD患者76例,按随机数字表分为对照组38例,进行常规康复训练,研究组38例,进行双重任务训练联合渐进性下蹲式抗阻训练。比较两组干预前后运动功能[Fugl-Meyer运动功能量表(FMA)]、平衡功能[Berg平衡功能量表(BBS)]、心肺耐力[10 min步行测试(10 MW)]及认知功能[蒙特利尔认知评估量表(MoCA)]。结果干预后,研究组FMA上肢(53.43±5.02)分、下肢(28.58±2.47)分及FMA总分(82.02±4.13)分均高于对照组的(44.72±4.76)分、(22.05±3.18)分、(66.77±4.87)分;BBS评分(22.82±1.53)分高于对照组(19.57±1.39)分,10 MW(15.27±6.04)s短于对照组(18.56±6.45)s,差异有统计学意义(P<0.05)。研究组MoCA各维度评分及总分均高于对照组,差异有统计学意义(P<0.05)。结论采用双重任务训练联合渐进性下蹲式抗阻训练干预PD患者,可有助于提升患者运动功能、平衡功能及认知功能,并改善心肺耐力。

基于双通道Transformer模型的多维信号故障诊断方法

感应电机在现代工业中有十分重要的作用。然而,电机长时间运行后会变得疲劳从而导致灾难性后果。由于电机故障诊断本质是对电机的时间信号分类,该研究提出双通道Transformer模型,该模型利用电流和振动信号进行诊断,并通过连续小波变换提取频域特征作为输入。双通道Transformer模型将数据的时域和频域信号分别通过Transformer模型,这种替代不仅可以提取时间特征,还可以提取空间特征。实验结果表明,所提出的模型可以提供高达95.36%的诊断准确率,证明其在电机故障诊断中的有效性。与传统的单信号故障诊断方法相比,该模型具有更好的鲁棒性和准确性。

Dual-Tasking as Diagnostic and Rehabilitation Tool in Traumatic Brain Injury Patients

Objective: Purpose of this study was to investigate the behavioral and brain activity impairments in patients after moderate traumatic brain injury (mTBI) in comparison with the normal ranges while dual-tasks performing. We would like to evaluate dual-tasking as diagnostic and rehabilitation tool and to test hypothesis of brain aging after mTBI. Material and Methods: Electroencephalographic (EEG), stabilographic and clinical study was performed in 11 patients (mean age 28.8 ± 8.4 years) for up to 1 - 12 months after a mTBI in comparison with 17 healthy subjects (26.7 ± 5.1 years). All the participants performed two motor and two cognitive tasks presented separately, and simultaneously (dual-tasking). Results: Clinical examination revealed predominantly cognitive deficit in mTBI patients with intact postural control. EEG data demonstrated coherence decrease for slow (delta-theta) rhythms in frontal-temporal areas predominantly for left hemisphere during cognitive tasks performance. In contrast, EEG coherence for slow spectral bands increased in the same areas in healthy volunteers. EEG coherence increased for fast spectral bands—alpha2 and beta, predominantly in right hemisphere while both healthy adults and patients performed motor components of dual tasks. Rehabilitation course with dual tasks, led to a predominant reduction in cognitive deficits, and EEG coherence increases at the frontal-temporal areas of the left hemisphere. Conclusions: Dual-tasks may be used as diagnostic tool in patients after mTBI. This approach demonstrates predominant cognitive deficit, and left hemispheric dysfunction in patients similar to elderly persons and support the hypothesis of brain aging after TBI. Pilot studies also suggested rehabilitation effect of dual-tasking in mTBI patients.