GO methodology is a success-oriented method for system reliability analysis. There are components with multi-fault modes in repairable systems. It is a problem to use the existing GO method to make reliability analysi...GO methodology is a success-oriented method for system reliability analysis. There are components with multi-fault modes in repairable systems. It is a problem to use the existing GO method to make reliability analysis of such repairable systems. A new GO method for reliability analysis of such repairable systems with multifault modes was presented. Firstly, calculation equations of reliability parameters of operators which were used to describe components with multi-fault modes in reparable systems were derived based on Markov process theory. Then, this new GO method was applied in reliability analysis of a hydraulic transmission oil supply system( HTOSS) of a power-shift steering transmission at low and high speeds. Finally,Compared with fault tree analysis( FTA) and Monte Carlo simulation,the results show that this new GO method is correct and suitable for reliability analysis of repairable system with multi-fault modes.展开更多
A method of multiple outputs least squares support vector regression （LS-SVR） was developed and described in detail, with the radial basis function （RBF） as the kernel function. The method was applied to predict t...A method of multiple outputs least squares support vector regression （LS-SVR） was developed and described in detail, with the radial basis function （RBF） as the kernel function. The method was applied to predict the future state of the power-shift steering transmission （PSST）. A prediction model of PSST was gotten with multiple outputs LS-SVR. The model performance was greatly influenced by the penalty parameter γ and kernel parameter σ2 which were optimized using cross validation method. The training and prediction of the model were done with spectrometric oil analysis data. The predictive and actual values were compared and a fault in the second PSST was found. The research proved that this method had good accuracy in PSST fault prediction, and any possible problem in PSST could be found through a comparative analysis.展开更多
为解决传统双有源桥(dual active bridge,DAB)变换器在宽输入电压工况下无法同时实现零回流功率和全局软开关的问题,提出了一种基于LCL-T谐振型DAB变换器的改进三重移相(improved triple-phase-shift,ITPS)调制策略。首先,对LCL-T谐振型...为解决传统双有源桥(dual active bridge,DAB)变换器在宽输入电压工况下无法同时实现零回流功率和全局软开关的问题,提出了一种基于LCL-T谐振型DAB变换器的改进三重移相(improved triple-phase-shift,ITPS)调制策略。首先,对LCL-T谐振型DAB变换器的功率传输特性和软开关特性进行分析,推导出不同电压转换比下无回流功率的控制量表达式。然后,利用LCL谐振网络的对称特性和考虑开关管寄生电容影响下的零电压开关(zero voltage switching,ZVS)约束条件,推导出全工况连续、形式统一、计算量小的ITPS调制控制量表达式,并对调制轨迹进行优化。最后,设计了一台1 kW的实验样机进行调制策略有效性的验证。实验结果表明,与传统调制策略相比,ITPS调制策略具有较宽输入电压范围、无回流功率及全局软开关的优势。展开更多
大规模分布式新能源接入导致新型配电系统面临“节点-网络”双重灵活性不足风险,使得规划配置智能混合储能软开关(hybrid energy storage system-soft open point,HESSSOP),实现节点型与网络型异质灵活资源协同控制,成为提升节点灵活调...大规模分布式新能源接入导致新型配电系统面临“节点-网络”双重灵活性不足风险,使得规划配置智能混合储能软开关(hybrid energy storage system-soft open point,HESSSOP),实现节点型与网络型异质灵活资源协同控制,成为提升节点灵活调节支撑和网络传输安全裕度的重要技术手段。对此,建立面向HESS-SOP融入支撑“节点-网络”双重灵活性的新型配电系统协同规划-运行模型。首先,研究SOP引入HESS组成HESS-SOP的拓扑结构和联合调节特性;然后,引入转移分布因子以线路为视角建立含HESSSOP的新型配电系统灵活性供需平衡模型,解析“节点-网络”灵活性供需平衡机理,并建立“节点-网络”双维度灵活性指标;其次,采用有功潮流灵敏度法与希尔伯特-黄变换法对HESS-SOP分别进行选址与初始参数配置,并建立考虑HESS-SOP“节点-网络”双重灵活性调控潜力的规划-运行联合优化模型,并采用混合算法进行求解;最后,基于改进的IEEE33节点系统开展算例分析。结果表明:所提出的灵活性指标能准确量化评估系统“节点-网络”双维度灵活性,所建立的考虑HESS-SOP灵活性调控潜力的规划-运行联合优化模型能有效提高配电系统运行的经济性与灵活性。展开更多
This research presents an advanced study on the modeling and stability analysis of electro-hydraulic control modules used in intelligent chassis systems.Firstly,a comprehensive nonlinear mathematical model of the elec...This research presents an advanced study on the modeling and stability analysis of electro-hydraulic control modules used in intelligent chassis systems.Firstly,a comprehensive nonlinear mathematical model of the electro-hydraulic power-shift system is developed,incorporating pipeline characteristics through impedance analysis and examining coupling effects between the pilot solenoid valve,main valve,and pipeline.Then,the model’s accuracy is validated through experimental testing,demonstrating high precision and minimal model errors.A comparative analysis between simulation data(both with and without pipeline characteristics)and experimental results reveals that the model considering pipeline parameters aligns more closely with experimental data,highlighting its superior accuracy.The research further explores the influence of key factors on system stability,including damping coefficient,feedback cavity orifice diameter,spring stiffness,pipeline length,and pipeline diameter.Significant findings include the critical impact of damping coefficient,orifice diameter,and pipeline length on stability,while spring stiffness has a minimal effect.These findings provide valuable insights for optimizing electro-hydraulic control modules in intelligent chassis systems,with practical implications for automotive and construction machinery applications.展开更多
基金Technical Basis Projects of China's MIIT(No.2012090003)
文摘GO methodology is a success-oriented method for system reliability analysis. There are components with multi-fault modes in repairable systems. It is a problem to use the existing GO method to make reliability analysis of such repairable systems. A new GO method for reliability analysis of such repairable systems with multifault modes was presented. Firstly, calculation equations of reliability parameters of operators which were used to describe components with multi-fault modes in reparable systems were derived based on Markov process theory. Then, this new GO method was applied in reliability analysis of a hydraulic transmission oil supply system( HTOSS) of a power-shift steering transmission at low and high speeds. Finally,Compared with fault tree analysis( FTA) and Monte Carlo simulation,the results show that this new GO method is correct and suitable for reliability analysis of repairable system with multi-fault modes.
基金Supported by the Ministerial Level Advanced Research Foundation(3031030)the"111"Project(B08043)
文摘A method of multiple outputs least squares support vector regression （LS-SVR） was developed and described in detail, with the radial basis function （RBF） as the kernel function. The method was applied to predict the future state of the power-shift steering transmission （PSST）. A prediction model of PSST was gotten with multiple outputs LS-SVR. The model performance was greatly influenced by the penalty parameter γ and kernel parameter σ2 which were optimized using cross validation method. The training and prediction of the model were done with spectrometric oil analysis data. The predictive and actual values were compared and a fault in the second PSST was found. The research proved that this method had good accuracy in PSST fault prediction, and any possible problem in PSST could be found through a comparative analysis.
文摘为解决传统双有源桥(dual active bridge,DAB)变换器在宽输入电压工况下无法同时实现零回流功率和全局软开关的问题,提出了一种基于LCL-T谐振型DAB变换器的改进三重移相(improved triple-phase-shift,ITPS)调制策略。首先,对LCL-T谐振型DAB变换器的功率传输特性和软开关特性进行分析,推导出不同电压转换比下无回流功率的控制量表达式。然后,利用LCL谐振网络的对称特性和考虑开关管寄生电容影响下的零电压开关(zero voltage switching,ZVS)约束条件,推导出全工况连续、形式统一、计算量小的ITPS调制控制量表达式,并对调制轨迹进行优化。最后,设计了一台1 kW的实验样机进行调制策略有效性的验证。实验结果表明,与传统调制策略相比,ITPS调制策略具有较宽输入电压范围、无回流功率及全局软开关的优势。
文摘大规模分布式新能源接入导致新型配电系统面临“节点-网络”双重灵活性不足风险,使得规划配置智能混合储能软开关(hybrid energy storage system-soft open point,HESSSOP),实现节点型与网络型异质灵活资源协同控制,成为提升节点灵活调节支撑和网络传输安全裕度的重要技术手段。对此,建立面向HESS-SOP融入支撑“节点-网络”双重灵活性的新型配电系统协同规划-运行模型。首先,研究SOP引入HESS组成HESS-SOP的拓扑结构和联合调节特性;然后,引入转移分布因子以线路为视角建立含HESSSOP的新型配电系统灵活性供需平衡模型,解析“节点-网络”灵活性供需平衡机理,并建立“节点-网络”双维度灵活性指标;其次,采用有功潮流灵敏度法与希尔伯特-黄变换法对HESS-SOP分别进行选址与初始参数配置,并建立考虑HESS-SOP“节点-网络”双重灵活性调控潜力的规划-运行联合优化模型,并采用混合算法进行求解;最后,基于改进的IEEE33节点系统开展算例分析。结果表明:所提出的灵活性指标能准确量化评估系统“节点-网络”双维度灵活性,所建立的考虑HESS-SOP灵活性调控潜力的规划-运行联合优化模型能有效提高配电系统运行的经济性与灵活性。
基金Supported by the Basic Product Innovation Plan for Vehicle Power Scientific Research Project(Grant No.JCCPCX201704).
文摘This research presents an advanced study on the modeling and stability analysis of electro-hydraulic control modules used in intelligent chassis systems.Firstly,a comprehensive nonlinear mathematical model of the electro-hydraulic power-shift system is developed,incorporating pipeline characteristics through impedance analysis and examining coupling effects between the pilot solenoid valve,main valve,and pipeline.Then,the model’s accuracy is validated through experimental testing,demonstrating high precision and minimal model errors.A comparative analysis between simulation data(both with and without pipeline characteristics)and experimental results reveals that the model considering pipeline parameters aligns more closely with experimental data,highlighting its superior accuracy.The research further explores the influence of key factors on system stability,including damping coefficient,feedback cavity orifice diameter,spring stiffness,pipeline length,and pipeline diameter.Significant findings include the critical impact of damping coefficient,orifice diameter,and pipeline length on stability,while spring stiffness has a minimal effect.These findings provide valuable insights for optimizing electro-hydraulic control modules in intelligent chassis systems,with practical implications for automotive and construction machinery applications.
