单相开路故障的五相永磁同步电机(permanent-magnet synchronous motor,PMSM)采用有限集模型预测转矩和磁链控制(finite-control-set model predictive torque and flux control,FCS-MPTFC)策略,存在转矩脉动大、价值函数的权重系数整...单相开路故障的五相永磁同步电机(permanent-magnet synchronous motor,PMSM)采用有限集模型预测转矩和磁链控制(finite-control-set model predictive torque and flux control,FCS-MPTFC)策略,存在转矩脉动大、价值函数的权重系数整定困难、迭代计算量大以及共模电压(commonmode voltage,CMV)高等问题。为此,该文提出一种简化FCS-MPTFC策略。首先,建立五相PMSM在单相开路故障情况下的数学模型,并分析CMV产生的机理。其次,以抑制3次谐波电流的原则合成等幅值虚拟电压矢量(virtual voltage vector,V^(3)),并将转矩和磁链价值函数等效转化为电压价值函数,同时采用无差拍控制思想计算出参考电压矢量,进而通过合理划分扇区,直接获得最优V^(3)。最后,选择方向相反的两个基电压矢量代替零矢量,以减小开路故障下的CMV。仿真和实验结果表明:所提控制策略不仅能抑制单相开路故障导致的转矩脉动、降低计算负荷和CMV、抑制电流谐波,而且具有优良的稳态和动态性能。展开更多
To address the performance degradation of permanent magnet synchronous motor(PMSM)drives caused by parameter mismatches between actual motor and ideal model in complex industrial environment,an improved model predicti...To address the performance degradation of permanent magnet synchronous motor(PMSM)drives caused by parameter mismatches between actual motor and ideal model in complex industrial environment,an improved model predictive voltage control(I-MPVC)approach without motor parameters is presented in this article.Unlike traditional MPVC where accurate motor parameters are heavily relied on,a motor parameter-independent(MPI)prediction model is constructed to eliminate parameter dependency.Firstly,an incremental voltage prediction model is developed where the influence of resistance and flux linkage mismatches is reduced.Then,an inductance parameter-independent(IPI)factor model,which solely relies on the current and voltage information,is further designed.Besides,the proposed approach takes lower computational complexity,as well as simpler parameter tuning steps,which offers significant benefits for real-time applications in industrial fields.Finally,experiments are conducted to validate the feasibility and superiority of the proposed approach.展开更多
针对传统谐振控制器与PI控制器并联(PIR)无法克服积分环节饱和等因素引起的系统动态过程中超调震荡问题,提出了一种改进双环自抗扰谐振控制器(dual-loop active disturbance rejection control,DLADRC)。DLADRC速度环与电流环均采用自...针对传统谐振控制器与PI控制器并联(PIR)无法克服积分环节饱和等因素引起的系统动态过程中超调震荡问题,提出了一种改进双环自抗扰谐振控制器(dual-loop active disturbance rejection control,DLADRC)。DLADRC速度环与电流环均采用自抗扰控制,速度环采用传统的自抗扰控制。电流环采用一种改进的谐振扩张状态观测器,将观测电流作为谐振控制器的输入,令谐振控制器的输出直接作用到电流环输出,从而降低了谐振电流环设计的复杂性。双环自抗扰谐振控制器保留了谐振控制器抑制特定频率谐波电流的特性,同时优化了系统的超调量与调节时间,有效提升了谐振控制系统的动态性能。仿真结果验证DLADRC系统的有效性。展开更多
永磁同步电机的模型预测控制是目前电机控制技术的研究热点之一,传统的单矢量模型预测电流控制(Model Predictive Current Control,MPCC)方法每个周期只有1个电压矢量作用,因此稳态性能较差,而且MPCC的控制性能受电机参数的影响较大。...永磁同步电机的模型预测控制是目前电机控制技术的研究热点之一,传统的单矢量模型预测电流控制(Model Predictive Current Control,MPCC)方法每个周期只有1个电压矢量作用,因此稳态性能较差,而且MPCC的控制性能受电机参数的影响较大。针对上述问题,提出了一种改进方法,即通过改进扩张状态观测器增加MPCC对电机参数的鲁棒性,结合一种新的三矢量模型预测控制方法来改善MPCC特性。仿真结果验证了本文所提方法的有效性。展开更多
Spinal cord injury necessitates effective rehabilitation strategies, with exercise therapies showing promise in promoting recovery. This study investigated the impact of rehabilitation exercise on functional recovery ...Spinal cord injury necessitates effective rehabilitation strategies, with exercise therapies showing promise in promoting recovery. This study investigated the impact of rehabilitation exercise on functional recovery and morphological changes following thoracic contusive spinal cord injury. After a 7-day recovery period after spinal cord injury, mice were assigned to either a trained group(10 weeks of voluntary running wheel or forced treadmill exercise) or an untrained group. Bi-weekly assessments revealed that the exercise-trained group, particularly the voluntary wheel exercise subgroup, displayed significantly improved locomotor recovery, more plasticity of dopaminergic and serotonin modulation compared with the untrained group. Additionally, exercise interventions led to gait pattern restoration and enhanced transcranial magnetic motor-evoked potentials. Despite consistent injury areas across groups, exercise training promoted terminal innervation of descending axons. In summary, voluntary wheel exercise shows promise for enhancing outcomes after thoracic contusive spinal cord injury, emphasizing the role of exercise modality in promoting recovery and morphological changes in spinal cord injuries. Our findings will influence future strategies for rehabilitation exercises, restoring functional movement after spinal cord injury.展开更多
Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor neurons.Early bilateral limb involvement significantly affects patients'daily lives ...Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor neurons.Early bilateral limb involvement significantly affects patients'daily lives and may lead them to be confined to bed.However,the effect of upper and lower motor neuron impairment and other risk factors on bilateral limb involvement is unclear.To address this issue,we retrospectively collected data from 586 amyotrophic lateral sclerosis patients with limb onset diagnosed at Peking University Third Hospital between January 2020 and May 2022.A univariate analysis revealed no significant differences in the time intervals of spread in different directions between individuals with upper motor neuron-dominant amyotrophic lateral sclerosis and those with classic amyotrophic lateral sclerosis.We used causal directed acyclic graphs for risk factor determination and Cox proportional hazards models to investigate the association between the duration of bilateral limb involvement and clinical baseline characteristics in amyotrophic lateral sclerosis patients.Multiple factor analyses revealed that higher upper motor neuron scores(hazard ratio[HR]=1.05,95%confidence interval[CI]=1.01–1.09,P=0.018),onset in the left limb(HR=0.72,95%CI=0.58–0.89,P=0.002),and a horizontal pattern of progression(HR=0.46,95%CI=0.37–0.58,P<0.001)were risk factors for a shorter interval until bilateral limb involvement.The results demonstrated that a greater degree of upper motor neuron involvement might cause contralateral limb involvement to progress more quickly in limb-onset amyotrophic lateral sclerosis patients.These findings may improve the management of amyotrophic lateral sclerosis patients with limb onset and the prediction of patient prognosis.展开更多
Objective: To investigate the effect of a self-developed balance rhythm dance program on the rehabilitation of motor function and the reduction of fall risk in elderly women with diminished balance function. Methods: ...Objective: To investigate the effect of a self-developed balance rhythm dance program on the rehabilitation of motor function and the reduction of fall risk in elderly women with diminished balance function. Methods: Fifty elderly women with reduced balance function, admitted to the Qingbar Elderly Care Center of Chongqing Medical University from December 2022 to December 2023, were randomly selected and divided into two groups. The aerobic exercise group (25 patients) received traditional treatment and rehabilitation nursing, while the balance rhythm dance intervention group (25 patients) received the balance rhythm dance intervention in addition to traditional treatment and rehabilitation nursing. The Unified Parkinson’s Disease Rating Scale (UPDRS) and Berg Balance Scale (BBS) were used as evaluation indicators to compare the intervention effects between the two groups. Results: The data revealed that the balance rhythm dance intervention significantly improved the motor ability and balance function of elderly women in the intervention group (P < 0.01), with statistically significant differences observed. Conclusion: The balance rhythm dance program plays a critical role in promoting the rehabilitation of motor function and balance ability in elderly women, effectively enhancing their quality of life.展开更多
文摘单相开路故障的五相永磁同步电机(permanent-magnet synchronous motor,PMSM)采用有限集模型预测转矩和磁链控制(finite-control-set model predictive torque and flux control,FCS-MPTFC)策略,存在转矩脉动大、价值函数的权重系数整定困难、迭代计算量大以及共模电压(commonmode voltage,CMV)高等问题。为此,该文提出一种简化FCS-MPTFC策略。首先,建立五相PMSM在单相开路故障情况下的数学模型,并分析CMV产生的机理。其次,以抑制3次谐波电流的原则合成等幅值虚拟电压矢量(virtual voltage vector,V^(3)),并将转矩和磁链价值函数等效转化为电压价值函数,同时采用无差拍控制思想计算出参考电压矢量,进而通过合理划分扇区,直接获得最优V^(3)。最后,选择方向相反的两个基电压矢量代替零矢量,以减小开路故障下的CMV。仿真和实验结果表明:所提控制策略不仅能抑制单相开路故障导致的转矩脉动、降低计算负荷和CMV、抑制电流谐波,而且具有优良的稳态和动态性能。
基金supported in part by the National Natural Science Foundation of China under Grant 52377036in part by the Outstanding Talents Project of North China University of Technology。
文摘To address the performance degradation of permanent magnet synchronous motor(PMSM)drives caused by parameter mismatches between actual motor and ideal model in complex industrial environment,an improved model predictive voltage control(I-MPVC)approach without motor parameters is presented in this article.Unlike traditional MPVC where accurate motor parameters are heavily relied on,a motor parameter-independent(MPI)prediction model is constructed to eliminate parameter dependency.Firstly,an incremental voltage prediction model is developed where the influence of resistance and flux linkage mismatches is reduced.Then,an inductance parameter-independent(IPI)factor model,which solely relies on the current and voltage information,is further designed.Besides,the proposed approach takes lower computational complexity,as well as simpler parameter tuning steps,which offers significant benefits for real-time applications in industrial fields.Finally,experiments are conducted to validate the feasibility and superiority of the proposed approach.
文摘针对传统谐振控制器与PI控制器并联(PIR)无法克服积分环节饱和等因素引起的系统动态过程中超调震荡问题,提出了一种改进双环自抗扰谐振控制器(dual-loop active disturbance rejection control,DLADRC)。DLADRC速度环与电流环均采用自抗扰控制,速度环采用传统的自抗扰控制。电流环采用一种改进的谐振扩张状态观测器,将观测电流作为谐振控制器的输入,令谐振控制器的输出直接作用到电流环输出,从而降低了谐振电流环设计的复杂性。双环自抗扰谐振控制器保留了谐振控制器抑制特定频率谐波电流的特性,同时优化了系统的超调量与调节时间,有效提升了谐振控制系统的动态性能。仿真结果验证DLADRC系统的有效性。
文摘永磁同步电机的模型预测控制是目前电机控制技术的研究热点之一,传统的单矢量模型预测电流控制(Model Predictive Current Control,MPCC)方法每个周期只有1个电压矢量作用,因此稳态性能较差,而且MPCC的控制性能受电机参数的影响较大。针对上述问题,提出了一种改进方法,即通过改进扩张状态观测器增加MPCC对电机参数的鲁棒性,结合一种新的三矢量模型预测控制方法来改善MPCC特性。仿真结果验证了本文所提方法的有效性。
基金supported by the NIH (R01NS103481, R01NS111776, and R01NS131489)Indiana Department of Health (ISDH58180)(all to WW)。
文摘Spinal cord injury necessitates effective rehabilitation strategies, with exercise therapies showing promise in promoting recovery. This study investigated the impact of rehabilitation exercise on functional recovery and morphological changes following thoracic contusive spinal cord injury. After a 7-day recovery period after spinal cord injury, mice were assigned to either a trained group(10 weeks of voluntary running wheel or forced treadmill exercise) or an untrained group. Bi-weekly assessments revealed that the exercise-trained group, particularly the voluntary wheel exercise subgroup, displayed significantly improved locomotor recovery, more plasticity of dopaminergic and serotonin modulation compared with the untrained group. Additionally, exercise interventions led to gait pattern restoration and enhanced transcranial magnetic motor-evoked potentials. Despite consistent injury areas across groups, exercise training promoted terminal innervation of descending axons. In summary, voluntary wheel exercise shows promise for enhancing outcomes after thoracic contusive spinal cord injury, emphasizing the role of exercise modality in promoting recovery and morphological changes in spinal cord injuries. Our findings will influence future strategies for rehabilitation exercises, restoring functional movement after spinal cord injury.
基金supported by the National Natural Science Foundation of China,Nos.82071426,81873784Clinical Cohort Construction Program of Peking University Third Hospital,No.BYSYDL2019002(all to DF)。
文摘Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor neurons.Early bilateral limb involvement significantly affects patients'daily lives and may lead them to be confined to bed.However,the effect of upper and lower motor neuron impairment and other risk factors on bilateral limb involvement is unclear.To address this issue,we retrospectively collected data from 586 amyotrophic lateral sclerosis patients with limb onset diagnosed at Peking University Third Hospital between January 2020 and May 2022.A univariate analysis revealed no significant differences in the time intervals of spread in different directions between individuals with upper motor neuron-dominant amyotrophic lateral sclerosis and those with classic amyotrophic lateral sclerosis.We used causal directed acyclic graphs for risk factor determination and Cox proportional hazards models to investigate the association between the duration of bilateral limb involvement and clinical baseline characteristics in amyotrophic lateral sclerosis patients.Multiple factor analyses revealed that higher upper motor neuron scores(hazard ratio[HR]=1.05,95%confidence interval[CI]=1.01–1.09,P=0.018),onset in the left limb(HR=0.72,95%CI=0.58–0.89,P=0.002),and a horizontal pattern of progression(HR=0.46,95%CI=0.37–0.58,P<0.001)were risk factors for a shorter interval until bilateral limb involvement.The results demonstrated that a greater degree of upper motor neuron involvement might cause contralateral limb involvement to progress more quickly in limb-onset amyotrophic lateral sclerosis patients.These findings may improve the management of amyotrophic lateral sclerosis patients with limb onset and the prediction of patient prognosis.
基金Chongqing Sports Scientific Research Project“Research and Development of Balance Rhythm Dance and Its Application in Reducing Fall Risk in Older Women”(Project No.D202209)Chongqing Nursing Vocational College College-level Project“Research on the Talent Training Model of Field Engineers in the Intelligent Health Care Sector Based on Rehabilitation Assistive Devices under the‘Integration of Science and Education’Approach”(Project No.Y202307)+1 种基金Chongqing Science and Technology Bureau Research Project“Investigating the Impact of Electro-acupuncture Applied to Antagonist Muscles on Walking Ability in Stroke Patients with Hemiplegia Based on the Principle of Reciprocal Inhibition”(Project No.CSTC2019JXJL130019)Chongqing Traditional Chinese Medicine Hospital Research Project“The Alterations in the Pelvic Floor Muscle Group Following Acupuncture Treatment for Postpartum Stress Urinary Incontinence Were Evaluated Using SWE Technology”(Project No.jxyn2021-2-23)。
文摘Objective: To investigate the effect of a self-developed balance rhythm dance program on the rehabilitation of motor function and the reduction of fall risk in elderly women with diminished balance function. Methods: Fifty elderly women with reduced balance function, admitted to the Qingbar Elderly Care Center of Chongqing Medical University from December 2022 to December 2023, were randomly selected and divided into two groups. The aerobic exercise group (25 patients) received traditional treatment and rehabilitation nursing, while the balance rhythm dance intervention group (25 patients) received the balance rhythm dance intervention in addition to traditional treatment and rehabilitation nursing. The Unified Parkinson’s Disease Rating Scale (UPDRS) and Berg Balance Scale (BBS) were used as evaluation indicators to compare the intervention effects between the two groups. Results: The data revealed that the balance rhythm dance intervention significantly improved the motor ability and balance function of elderly women in the intervention group (P < 0.01), with statistically significant differences observed. Conclusion: The balance rhythm dance program plays a critical role in promoting the rehabilitation of motor function and balance ability in elderly women, effectively enhancing their quality of life.
