电动汽车驱动用铁氧体电机多用分布式定子绕组。以60 k W电动汽车驱动用电机为例,采用计算机仿真方法,研究分布绕组铁氧体电机电磁设计中极槽配合、磁钢布置对转矩能力和性能的影响,同时讨论铁氧体磁钢的不可逆退磁问题,得出能够指导工...电动汽车驱动用铁氧体电机多用分布式定子绕组。以60 k W电动汽车驱动用电机为例,采用计算机仿真方法,研究分布绕组铁氧体电机电磁设计中极槽配合、磁钢布置对转矩能力和性能的影响,同时讨论铁氧体磁钢的不可逆退磁问题,得出能够指导工程实践的有益结论。展开更多
固定关断角的角度位置控制APC(angular position control)方法在负载和转速变化较大的场合下适应能力较低。为此,提出了一种基于遗传算法的开关磁阻电机SRM(switched reluctance motor)关断角优化策略。结合非线性磁链曲线和实测特定位...固定关断角的角度位置控制APC(angular position control)方法在负载和转速变化较大的场合下适应能力较低。为此,提出了一种基于遗传算法的开关磁阻电机SRM(switched reluctance motor)关断角优化策略。结合非线性磁链曲线和实测特定位置点处的磁链数据,得到优化后磁链准线型模型曲线,推导出电机平均转矩的解析式。利用遗传算法优良的全局搜索寻优能力,将1个电气周期内平均转矩作为优化目标来寻找不同转速及峰值电流下的最佳关断角。仿真结果表明在高速运行时,电机转矩输出能力较固定关断角APC有较大的提升,并通过实验论证了基于遗传算法的关断角优化策略的有效性和可行性。展开更多
A real-size experiment on 11 tubes was done to study the performance o f centrifugal concrete-filled steel tubes under bending and torsion. This pape r first introduces the relevant operating method,equipment,subjects...A real-size experiment on 11 tubes was done to study the performance o f centrifugal concrete-filled steel tubes under bending and torsion. This pape r first introduces the relevant operating method,equipment,subjects and process es. The factors that affect deformation and stiffness and the break mechanism un der different loading were studied. Experimental stress analysis showed that the values of practical critical stress of steel tubes accorded well with the MISES Yielding Rule. The correlative equation (on the bearing capacity of a structura l member under bending and torsion) deduced in this study may provide valuable reference for the design of this structural member.展开更多
While modem prestressed techniques have improved the torsion properties of high-strength concrete （HSC） composite beams with prestressed steel （PS） boxes, no research has been reported in either the national or in...While modem prestressed techniques have improved the torsion properties of high-strength concrete （HSC） composite beams with prestressed steel （PS） boxes, no research has been reported in either the national or international literature on the an- ti-torque and composite torque properties of this type of beam. With the aim of understanding the torque properties of these beams, this paper presents results of ten comprehensive tests; three of these were based on stirrup spacings and prestressing levels as the main parameters, while the other seven were based on torsional rates. The torsion tests were conducted on the re- sults which established several key parameters, including curves of constant torsion, strain curves of steel torsion, strain distri- bution of steel beams and concrete, curves of bending-moment and mid-span deflection, as well as cross strain distribution.The prestressing impact-factor method was adopted to deduce semiempirical equations for cracking torque in such composite beams. Furthermore, this involves the use of the equation of ultimate torque based on tress-model-theory of the distortion an- gle, the calculated results show good agreement with the measured values. In summary, this paper offers theoretical analysis for future applications of HSC composite beams with PS boxes, and provides both validation of the methods employed and a reference point for on-going research on composite beams and related anti-torque studies.展开更多
文摘固定关断角的角度位置控制APC(angular position control)方法在负载和转速变化较大的场合下适应能力较低。为此,提出了一种基于遗传算法的开关磁阻电机SRM(switched reluctance motor)关断角优化策略。结合非线性磁链曲线和实测特定位置点处的磁链数据,得到优化后磁链准线型模型曲线,推导出电机平均转矩的解析式。利用遗传算法优良的全局搜索寻优能力,将1个电气周期内平均转矩作为优化目标来寻找不同转速及峰值电流下的最佳关断角。仿真结果表明在高速运行时,电机转矩输出能力较固定关断角APC有较大的提升,并通过实验论证了基于遗传算法的关断角优化策略的有效性和可行性。
文摘A real-size experiment on 11 tubes was done to study the performance o f centrifugal concrete-filled steel tubes under bending and torsion. This pape r first introduces the relevant operating method,equipment,subjects and process es. The factors that affect deformation and stiffness and the break mechanism un der different loading were studied. Experimental stress analysis showed that the values of practical critical stress of steel tubes accorded well with the MISES Yielding Rule. The correlative equation (on the bearing capacity of a structura l member under bending and torsion) deduced in this study may provide valuable reference for the design of this structural member.
基金supported by the National Natural Science Foundation of China (Grant No. 50879048)"948" Project of the Ministry of Water Resources of China (Grant No. 201127)
文摘While modem prestressed techniques have improved the torsion properties of high-strength concrete （HSC） composite beams with prestressed steel （PS） boxes, no research has been reported in either the national or international literature on the an- ti-torque and composite torque properties of this type of beam. With the aim of understanding the torque properties of these beams, this paper presents results of ten comprehensive tests; three of these were based on stirrup spacings and prestressing levels as the main parameters, while the other seven were based on torsional rates. The torsion tests were conducted on the re- sults which established several key parameters, including curves of constant torsion, strain curves of steel torsion, strain distri- bution of steel beams and concrete, curves of bending-moment and mid-span deflection, as well as cross strain distribution.The prestressing impact-factor method was adopted to deduce semiempirical equations for cracking torque in such composite beams. Furthermore, this involves the use of the equation of ultimate torque based on tress-model-theory of the distortion an- gle, the calculated results show good agreement with the measured values. In summary, this paper offers theoretical analysis for future applications of HSC composite beams with PS boxes, and provides both validation of the methods employed and a reference point for on-going research on composite beams and related anti-torque studies.
