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1.
陀螺漂移测试转台无刷直流力矩电机系统中存在波动力矩和负载力矩振动,这严重地影响了转台速率平稳度。为提高转台速率状态位置跟踪精度,设计了一种自适应补偿方法。该方法包含一个参自适应律和等效PID控制律,它利用前馈补偿原理,来估计电机中未知参数以及波动力矩和负载力矩参数并给与补偿。该自适应补偿方法保证了闭环系统全局稳定性和对期望位置信号的渐进跟踪。仿真结果证明:该方法有效地提高了转台速率状态跟踪精度。  相似文献   

2.
无刷直流力矩电机波动力矩的分析   总被引:1,自引:0,他引:1  
波动力矩是无刷直流力矩电机的一项重要技术指标。本文讨论了方波化无刷直流力矩电机的波动力矩产生的原因,其与定位力矩和驱动模式之间的制约关系,指出了一般情况下方波化力矩电机力矩波动的不可避免性。本文还分析并导出正弦化无刷直流力矩电机由电流的幅值偏差、相位偏差、恒定成分和谐波成分导致的波动力矩的表达式,实测了波动力矩曲线。理论分析与实测结果一致,经精心设计和调整,正弦化力矩电机的波动力矩已达±0.54%。  相似文献   

3.
无刷直流电动机作为控制力矩陀螺驱动电机,要求具有10倍的最大功率倍数,这给电机的设计带来很大难度。该提出的绕组换接运行,在满足控制力矩陀螺驱动要求的前提下,不但可以使电机最大功率倍数,从而使系统逆变器容量降低,同时可以大大降低系统的损耗,提高系统的运行效率。通过理论分析和样机试验证明了绕组换接的有效性。  相似文献   

4.
本文提出了无刷直流电动机的一种新型转子位置传感系统,结构简单可靠,能够提供准确的转子位置信息,适合于与电机系统的一体化。实验结果表明,该系统精度可以满足无刷直流电动机矢量变换的要求。  相似文献   

5.
无刷直流力矩电动机系统传函的精确描述   总被引:1,自引:1,他引:0  
本文介绍无刷直流力矩电动机系统结构与运行原理;采用Park变换建立了无刷直流力矩电动机系统的动态数学模型;通过频域分析,推出精确描述无刷直流力矩电动机系统特性的传递函数;讨论了无刷直流力矩电动机系统参数对整个控制系统的影响。  相似文献   

6.
无位置传感器无刷直流电动机起动新方法   总被引:2,自引:0,他引:2  
针对无刷直流电机在静止和低速状态下检测转子位置困难,提出了无刷直流电机采用无位置传感器控制策略时转子位置检测的一种新方法。基于定子电感是转子位置的函数,用该方法推导出三相无刷直流电动机在两相通电工作方式下的等效电感,并用简单的电子电路实现直流无刷电机无位置传感器的驱动控制。经实验验证,此方法对凸极无刷直流电动机起动是可行的。  相似文献   

7.
一种高精度无刷直流陀螺电机锁相稳速系统   总被引:2,自引:0,他引:2  
设计了一种两相无位置传感器无刷直流陀螺电机锁相稳速系统,单片机与可编程逻辑器的结合使系统以简单的电路实现了各种数字信号的处理。锁定时,电机反电势频率脉冲跟踪基准脉冲,电机稳速运行。试验表明:该系统稳速精度高,实用性强,可靠性高。  相似文献   

8.
陀螺漂移测试转台直流力矩电机系统中存在的非线性滞滑摩擦,使转台在PID控制下存在滞滑极限环。为提高转台定位精度,应用具有滞滑(stick-slip)摩擦的直流力矩电机系统模型,推导了一种补偿方法,对含有滞滑摩擦的PID控制转台直流力矩电机伺服系统进行滞滑摩擦补偿。在采用PID控制的转台电机系统定位工作状态下,这种滞滑补偿方法可以减小滞滑极限环的幅值。仿真结果证明了该补偿方法的有效性。  相似文献   

9.
无刷直流陀螺电机的高精度恒速控制   总被引:2,自引:1,他引:1  
介绍了一种能够实现三相绕组无刷直流陀螺电机的锁相恒速控制方法,所提出的定脉冲三相移电路是将高精度的参考脉冲信号移相成频率不变、相位差为120°的三组脉冲信号,分别与各相反电势检测整形的反馈信号进行相位比较,由该比较输出的数字脉冲信号直接控制电机的三相绕组导通工作。锁定时,使电机反电势的频率脉冲与参考脉冲成为一一对应的关系,电机就处于高精度恒速运行。通过样机试验,其恒速控制精度达到0.001%。  相似文献   

10.
本文针对故障诊断知识具有模糊性的特点,提出了一种基于模糊神经网络的故障诊断方法,将模糊理论与神经网络融合在一起,实现了对故障的模糊诊断.文中给出了模糊神经网络的结构和学习方法,并提出了一种阈值向量故障判别方法,使故障判别更具灵活性.并以无刷直流电机系统为对象,将该方法应用于系统的故障诊断,仿真结果表明,该方法是行之有效的.  相似文献   

11.
The sensitivity of a commercial torque transducer under oscillatory shear conditions is extended by about a factor 3–5 into the small torque region. This increased sensitivity is a result of a straightforward data treatment in the time domain termed “on the fly oversampling”. This method is enabled by the emergence of modern ADC-cards. The underlying ideas of oversampling together with a first experimental verification of this method are described in detail. Received: 22 August 2000 Accepted: 14 November 2000  相似文献   

12.
短路匝式传感器带来的干扰力矩是引起陀螺仪随机漂移的重要因素之一,减小该项干扰力矩对提高陀螺精度能够起到重要的作用。本文利用电磁感应定律和磁路分析法对干扰力矩进行了推导,并通过Ansoft maxwell软件对短路匝传感器不同参数情况下的干扰力矩进行仿真分析,得出了转子转角、激磁电压和激磁频率对干扰力矩的影响关系曲线,最后合理选择参数以保证干扰力矩在精度允许范围内。该分析结果对减小短路匝传感器的干扰力矩和减小陀螺仪的随机漂移都具有一定参考价值。  相似文献   

13.
Input torque is the main power to maintain bipedal walking of robot, and can be calculated from trajectory planning and dynamic modeling on biped robot. During bipedal walking, the input torque is usually required to be adjusted due to some uncertain parameters arising from objective or subjective factors in the dynamical model to maintain the pre-planned stable trajectory. Here, a planar 5-link biped robot is used as an illustrating example to investigate the effects of uncertain parameters on the input torques. Kine-matic equations of the biped robot are firstly established by the third-order spline curves based on the trajectory planning method, and the dynamic modeling is accomplished by taking both the certain and uncertain parameters into account. Next, several evaluation indices on input torques are intro-duced to perform sensitivity analysis of the input torque with respect to the uncertain parameters. Finally, based on the Monte Carlo simulation, the values of evaluation indices on input torques are presented, from which all the robot param-eters are classified into three categories, i.e., strongly sensi-tive, sensitive and almost insensitive parameters.  相似文献   

14.
The movement of the particles in acoustophoresis is driven by the acoustic radiation force acting on the particles. Particles with positive contrast factor tend to agglomerate once they are pushed by the primary force to the vicinity of the pressure node. The main driving force of this agglomeration is the interparticle force. In this study, the boundary element method is used to calculate the interparticle force and torque acting on a pair of spheroidal particles. The numerical results show that the interparticle force is dominant over the primary force when the spheroids are near the pressure nodal plane, similar to the case of two spheres. On contrary, the interparticle torque is insignificant compared to the primary torque, even when the spheroids are close to each other. The results also provide a preliminary study about how biological cells, which are mostly not spherical in shape, agglomerate and orient themselves in the vicinity of the pressure node.  相似文献   

15.
A method of optimal wheel torque determination for electric motor vehicles is presented. Electric motor vehicles are increasing with the rise of public interest in environmental protection. In the case of vehicles driven by controllable motors on each individual wheel, the determination of the wheel torque is an essential factor for efficient driving. In this research, a method of optimal torque determination has been formulated by using the variational principle to minimize frictional work done by the tires with the ground contact. Optimal torque on each wheel for a four-wheel vehicle was numerically obtained by solving the equations under several driving conditions. The result of the numerical simulation is useful as a guide to control the motor torque of electric vehicles for efficient driving.  相似文献   

16.
摆式积分陀螺加速度计的外环干扰力矩包括仪表外环轴的摩擦力矩和交叉轴加速度引起的交变力矩。作者分析了引起摆式积分陀螺加速度计外环干扰力矩的主要原因,提出一种在高精度三轴测试转台上分离摆式积分陀螺加速度计外环干扰力,测试摆式积分陀螺加速度计精度的试验方法。该试验采用三轴转台中环转动速度随动摆式积分陀螺加速度计外环进动角速度,同时摆式积分陀螺加速度计陀螺摆的输出轴在整个试验中保持水平,从而分离仪表外环干扰力的方案。通过对试验数据进行分析,得出外环干扰力的存在影响了摆式积分陀螺加速度计测试精度,为改善摆式陀螺加速度计工艺以提高摆式陀螺加速度计的测试精度提供了依据。  相似文献   

17.
Friction plays a key role in the efficiency and stability of the slip-controlled torque converter clutches. The effects of friction on the dynamics and stability of a slip-controlled torque converter clutch system using a bifurcation-analysis-based approach is presented in this paper. A three degree-of-freedom nonlinear driveline model with integral feedback action to control the clutch slip speed has been utilized for this study. The clutch interface friction is dependent on the slip speed and is a function of the static friction constant, μ 0, the low velocity friction constant μ 1, and the low velocity exponential rate, γ. Using one-parameter numerical continuation, local Hopf bifurcations of the subcritical type are observed as the friction parameters μ 1 and γ were varied at low slip speeds. The continuation results are verified using simulations of the full nonlinear model. Stick-slip and undesirable oscillations of the model inertia elements are observed for certain parameter values. As the slip speed is increased, the bifurcation instability occurs at an increasingly higher value of μ 1 signifying an improved tolerance of negative friction gradient at higher slip speeds. Smaller exponential rates γ are tolerated at higher slip speeds before the bifurcation instability occurs. For the range of parameter values considered, no bifurcations occur for a slip speeds higher than 3.4 and 4.5 rad/s with μ 1 and γ as the continuation parameters, respectively. These values of slip speeds are much lower than the system’s first mode of torsional vibration of 16 Hz (≈100 rad/s).  相似文献   

18.
介绍了磁场加转系统的工作原理和过程;通过对静电陀螺加转系统的加转力矩和加转时间的研究,分析了加转磁场转速等参数对加转力矩和加转时间的影响,推导出了相应公式,给出了加转磁场最佳转速的确定方法。研究结果表明:在其它参数不变时,存在最优加转磁场转速,使转子达到额定转速所需的加转时间最短。文中给出的确定该最优转速的方法是有效可行的;实际工作时加转磁场转速可在最优转速附近±314 s~(-1)范围内选取。  相似文献   

19.
对于截面含切口圆柱体的弹塑性自由扭转问题的分析,可按受力特点分为三个阶段:全弹性阶段、全塑性阶段和弹塑性阶段.每一阶段对应的分析方法不同,其中,在全弹性阶段可以采用有限差分法分析;在全塑性阶段可以按沙堆比拟的方法采用等倾曲面模拟;弹塑性阶段可以结合上述两种方法的结果和思路进行分析.利用差分法可以求出自由扭转截面内各离散点应力函数φ的数值解.本文推导了自由扭转的应力函数φ与J积分之间的关系,得出了自由扭转的应力函数与Ⅲ型裂纹的J积分之间的关系式.数值计算结果验证了本文方法的有效性和精确性.  相似文献   

20.
A non-linear attitude control method for a satellite with magnetic torque rods using the state-dependent Riccati equation (SDRE) technique has been developed. The magnetic torque caused by the interaction with the Earth's magnetic field and the magnetic moment of torque rods plays a role of the control torque. The detailed equations of motion for this system are presented using angular velocity and quaternions. The SDRE controller is developed for the non-linear systems which can be formed in pseudo-linear representations using the state-dependent coefficient (SDC) method without linearization procedure. The aim of this control system is to achieve a stable attitude within 5°, and minimize the control effort. The stability regions for the SDRE controlled satellite system are estimated through the investigation of the stability conditions developed for pseudo-linear systems and the application of Lyapunov's theorem. For comparisons, the Linear Quadratic Regulator (LQR) method using the solution of the algebraic Riccati equation (ARE) is also applied to this non-linear system. The performance of the SDRE non-linear control system demonstrates more robustness and stability than the LQR control system when subjected to a wide range of initial conditions.  相似文献   

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