A new type of piezoelectric electro-hydraulic servo valve system was proposed. And then multilayer piezoelectric actuator based on new piezoelectric ceramic material was used as the electricity-machine converter of th...A new type of piezoelectric electro-hydraulic servo valve system was proposed. And then multilayer piezoelectric actuator based on new piezoelectric ceramic material was used as the electricity-machine converter of the proposed piezoelectric electro-hydraulic servo valve. The proposed piezoelectric electro-hydraulic servo valve has ascendant performance compared with conventional ones. But the system is of high nonlinearity and uncertainty, it cannot achieve favorable control performance by conventional control method. To develop an efficient way to control piezoelectric electro-hydraulic servo valve system, a high-precise fuzzy control method with hysteresis nonlinear model in feedforward loop was proposed. The control method is separated into two parts: a feedforward loop with Preisach hysteresis nonlinear model and a feedback loop with high-precise fuzzy control. Experimental results show that the hysteresis loop and the maximum output hysteresis by the PID control method are 4.22% and 2.11 μm, respectively; the hysteresis loop and the maximum output hysteresis by the proposed control method respectively are 0.74% and 0.37 μm, respectively; the maximum tracking error by the PID control method for sine wave reference signal is about 5.02%, the maximum tracking error by the proposed control method for sine wave reference signal is about 0.85%.展开更多
A new tamping device which is driven by an electrohydraulic exciter was proposed to overcome the limitations of mechanically driven devices.The double-rod oscillation cylinder drives the tamping arm to realize vibrati...A new tamping device which is driven by an electrohydraulic exciter was proposed to overcome the limitations of mechanically driven devices.The double-rod oscillation cylinder drives the tamping arm to realize vibration.A new spin valve was designed in order to fulfill dynamic state requirements of the oscillation cylinder.Parametric analysis was carried out by establishing mathematic model.Then,the relationships among the structure of valve port and the frequency,amplitude,output shock force of the cylinder were researched.An experimental device of the electrohydraulic exciter was established to validate the theoretical results.The signals were acquired by AVANT dynamic signal analyser of vibration.The results show that new tamping device can satisfy all kinds of complex working conditions with the flexible adjustment of frequency and amplitude.展开更多
换流变压器阀侧套管是特高压直流输电系统中的重要组件,传统故障预警与状态评估方式借助于大量物理试验和人工数据采集。该文围绕阀侧套管开展数字孪生模型研究,提出了电力设备数字孪生模型构建规范,并基于实体套管几何模型等建立了阀...换流变压器阀侧套管是特高压直流输电系统中的重要组件,传统故障预警与状态评估方式借助于大量物理试验和人工数据采集。该文围绕阀侧套管开展数字孪生模型研究,提出了电力设备数字孪生模型构建规范,并基于实体套管几何模型等建立了阀侧套管孪生模型。研究表明:阀侧套管数字孪生模型可有效计及阀侧套管芯子绝缘材料在-40~120℃温变和10^(-1)~10^(3 )Hz频变的非线性特性,进一步应用阀侧套管孪生模型演算获得套管导电杆与绝缘油直接换热特性,且阀侧套管尾部温度接近变压器油温90℃。提出的阀侧套管数字孪生模型显著提高了阀侧套管电磁-热流耦合模型的计算速度,实现了阀侧套管运行状态平台可视化。应用该文提出的电热耦合非线性数学模型和换流变阀侧套管数字孪生平台,生成套管相关结构参数,生产制造了缩比阀侧套管并通过负极性截波雷电冲击575 k V电压系列现场试验。基于所提出的数字孪生模型结构,搭建了换流变阀侧套管数字孪生可视化平台,有效提高了阀侧套管运维及监测效率,实现了对于阀侧套管可视化监测及数字孪生技术的应用。展开更多
基金Project(2001AA423270) supported by the National High-Tech Research and Development Program of ChinaProject (2005037185) supported by the Postdoctoral Science Foundation of China
文摘A new type of piezoelectric electro-hydraulic servo valve system was proposed. And then multilayer piezoelectric actuator based on new piezoelectric ceramic material was used as the electricity-machine converter of the proposed piezoelectric electro-hydraulic servo valve. The proposed piezoelectric electro-hydraulic servo valve has ascendant performance compared with conventional ones. But the system is of high nonlinearity and uncertainty, it cannot achieve favorable control performance by conventional control method. To develop an efficient way to control piezoelectric electro-hydraulic servo valve system, a high-precise fuzzy control method with hysteresis nonlinear model in feedforward loop was proposed. The control method is separated into two parts: a feedforward loop with Preisach hysteresis nonlinear model and a feedback loop with high-precise fuzzy control. Experimental results show that the hysteresis loop and the maximum output hysteresis by the PID control method are 4.22% and 2.11 μm, respectively; the hysteresis loop and the maximum output hysteresis by the proposed control method respectively are 0.74% and 0.37 μm, respectively; the maximum tracking error by the PID control method for sine wave reference signal is about 5.02%, the maximum tracking error by the proposed control method for sine wave reference signal is about 0.85%.
基金Projects(50975252,51275499)supported by the National Natural Science Foundation of ChinaProject(2013CB035404)supported by the National Basic Research Program of ChinaProject(GZKF-201312)supported by Open Foundation of the State Key Laboratory of Fluid Power Transmission and Control,China
文摘A new tamping device which is driven by an electrohydraulic exciter was proposed to overcome the limitations of mechanically driven devices.The double-rod oscillation cylinder drives the tamping arm to realize vibration.A new spin valve was designed in order to fulfill dynamic state requirements of the oscillation cylinder.Parametric analysis was carried out by establishing mathematic model.Then,the relationships among the structure of valve port and the frequency,amplitude,output shock force of the cylinder were researched.An experimental device of the electrohydraulic exciter was established to validate the theoretical results.The signals were acquired by AVANT dynamic signal analyser of vibration.The results show that new tamping device can satisfy all kinds of complex working conditions with the flexible adjustment of frequency and amplitude.
文摘换流变压器阀侧套管是特高压直流输电系统中的重要组件,传统故障预警与状态评估方式借助于大量物理试验和人工数据采集。该文围绕阀侧套管开展数字孪生模型研究,提出了电力设备数字孪生模型构建规范,并基于实体套管几何模型等建立了阀侧套管孪生模型。研究表明:阀侧套管数字孪生模型可有效计及阀侧套管芯子绝缘材料在-40~120℃温变和10^(-1)~10^(3 )Hz频变的非线性特性,进一步应用阀侧套管孪生模型演算获得套管导电杆与绝缘油直接换热特性,且阀侧套管尾部温度接近变压器油温90℃。提出的阀侧套管数字孪生模型显著提高了阀侧套管电磁-热流耦合模型的计算速度,实现了阀侧套管运行状态平台可视化。应用该文提出的电热耦合非线性数学模型和换流变阀侧套管数字孪生平台,生成套管相关结构参数,生产制造了缩比阀侧套管并通过负极性截波雷电冲击575 k V电压系列现场试验。基于所提出的数字孪生模型结构,搭建了换流变阀侧套管数字孪生可视化平台,有效提高了阀侧套管运维及监测效率,实现了对于阀侧套管可视化监测及数字孪生技术的应用。
