提出一种基于磁悬浮控制力矩陀螺(magnetically suspended control moment gyroscope,MSCMG)金字塔构型的航天器姿态测控一体化控制方法,利用姿控回路中的执行机构,既进行航天器姿态测量,又进行航天器姿态控制,改变了传统姿控系统由姿...提出一种基于磁悬浮控制力矩陀螺(magnetically suspended control moment gyroscope,MSCMG)金字塔构型的航天器姿态测控一体化控制方法,利用姿控回路中的执行机构,既进行航天器姿态测量,又进行航天器姿态控制,改变了传统姿控系统由姿态敏感器、控制器、执行机构的组成方式。首先建立磁悬浮转子径向力矩模型,通过实时检测磁悬浮控制力矩陀螺中的磁轴承电流、磁悬浮转子位移、框架角速度,联立金字塔构型中的3个径向力矩模型求解出航天器的姿态角速度,再设计相应的姿态控制律和框架操纵律,实现航天器的姿态调节,仿真结果证明了该方法的正确性和有效性。展开更多
Calculated results of inertia moment of turbo-generator rotor can be quite different by methods used in load rejection tests. In view of fluctuation features of rotor speed rise curve during load rejection tests, the ...Calculated results of inertia moment of turbo-generator rotor can be quite different by methods used in load rejection tests. In view of fluctuation features of rotor speed rise curve during load rejection tests, the measurement principle of rotor inertia moment was expounded. Based on the measured data in load rejection tests for an imported type of domestic 300-MW generating unit, the rotor speed rise curve was fitted with three kinds of functions to get initial runup rate, but the obtained results differed a lot from each other. According to analysis on the mechanism of rotor speed rise, m=2 consecutive points averaging or FFT (Fast Fourier Transform) smoothing technology was introduced to process test data, and then the initial runup rate was determined by the method of linear fitting of rotor speed in the range of governing valve closing time. Although the obtained curves had a fluctuating shape, the results of rotor inertia moment for 50% and 100% load rejection tests were of good consistency.展开更多
The design of notch and barrier was optimized in order to improve the characteristics of constant torque while minimizing the cogging torque that occurs as a result of teeth and slot structure. The barrier was install...The design of notch and barrier was optimized in order to improve the characteristics of constant torque while minimizing the cogging torque that occurs as a result of teeth and slot structure. The barrier was installed in order to minimize the cogging torque and torque ripple by finite element method (FEM) with a reduced barrier width toward the center of magnetic pole. The position and width of notch, which can offset cogging torque, can be calculated with energy distribution of air-gap using Fourier series. The optimized model demonstrates a 60% decrease in the cogging torque, a 75.3% decrease in the torque ripple and a 3% increase in the operating torque when compared with the basic model.展开更多
The authors had invented the unique wind power unit composed of the large-sized front wind rotor,the small-sized rear wind rotor and the peculiar generator with the inner and the outer rotational armatures without the...The authors had invented the unique wind power unit composed of the large-sized front wind rotor,the small-sized rear wind rotor and the peculiar generator with the inner and the outer rotational armatures without the conventional stator.This unit is called "Intelligent Wind Power Unit" by the authors.The front and the rear wind rotors drive the inner and the outer armatures,respectively,while the rotational torque is counter-balanced between both armatures/wind rotors.This paper discusses experimentally the acoustic noise from the front and the rear wind rotors.The acoustic noise,in the counter-rotating operation,is induced mainly from the flow interaction between both rotors,and has the dominant power spectrum density at the frequency of the blade passing interaction.The noise is caused mainly from the turbulent fluctuation due to the flow separation on the blade,when the rear wind rotor stops or rotates in the same direction as the front wind rotor.展开更多
文摘提出一种基于磁悬浮控制力矩陀螺(magnetically suspended control moment gyroscope,MSCMG)金字塔构型的航天器姿态测控一体化控制方法,利用姿控回路中的执行机构,既进行航天器姿态测量,又进行航天器姿态控制,改变了传统姿控系统由姿态敏感器、控制器、执行机构的组成方式。首先建立磁悬浮转子径向力矩模型,通过实时检测磁悬浮控制力矩陀螺中的磁轴承电流、磁悬浮转子位移、框架角速度,联立金字塔构型中的3个径向力矩模型求解出航天器的姿态角速度,再设计相应的姿态控制律和框架操纵律,实现航天器的姿态调节,仿真结果证明了该方法的正确性和有效性。
文摘Calculated results of inertia moment of turbo-generator rotor can be quite different by methods used in load rejection tests. In view of fluctuation features of rotor speed rise curve during load rejection tests, the measurement principle of rotor inertia moment was expounded. Based on the measured data in load rejection tests for an imported type of domestic 300-MW generating unit, the rotor speed rise curve was fitted with three kinds of functions to get initial runup rate, but the obtained results differed a lot from each other. According to analysis on the mechanism of rotor speed rise, m=2 consecutive points averaging or FFT (Fast Fourier Transform) smoothing technology was introduced to process test data, and then the initial runup rate was determined by the method of linear fitting of rotor speed in the range of governing valve closing time. Although the obtained curves had a fluctuating shape, the results of rotor inertia moment for 50% and 100% load rejection tests were of good consistency.
基金Research financially supported by Human Resource Training Project for Regional Innovation of Ministry of Education,Science and Technology(MEST)National Research Foundation(NRF)the Second Stage of Brain Korea 21 Projects,Korea
文摘The design of notch and barrier was optimized in order to improve the characteristics of constant torque while minimizing the cogging torque that occurs as a result of teeth and slot structure. The barrier was installed in order to minimize the cogging torque and torque ripple by finite element method (FEM) with a reduced barrier width toward the center of magnetic pole. The position and width of notch, which can offset cogging torque, can be calculated with energy distribution of air-gap using Fourier series. The optimized model demonstrates a 60% decrease in the cogging torque, a 75.3% decrease in the torque ripple and a 3% increase in the operating torque when compared with the basic model.
基金co-sponsored by Research Project 2007 "Grand-in-aid for Scientific Research (c) (2) in Japan" and Research project:Grant-in-aid for JSPS fellow
文摘The authors had invented the unique wind power unit composed of the large-sized front wind rotor,the small-sized rear wind rotor and the peculiar generator with the inner and the outer rotational armatures without the conventional stator.This unit is called "Intelligent Wind Power Unit" by the authors.The front and the rear wind rotors drive the inner and the outer armatures,respectively,while the rotational torque is counter-balanced between both armatures/wind rotors.This paper discusses experimentally the acoustic noise from the front and the rear wind rotors.The acoustic noise,in the counter-rotating operation,is induced mainly from the flow interaction between both rotors,and has the dominant power spectrum density at the frequency of the blade passing interaction.The noise is caused mainly from the turbulent fluctuation due to the flow separation on the blade,when the rear wind rotor stops or rotates in the same direction as the front wind rotor.
