矩
- 与 矩 相关的网络例句 [注:此内容来源于网络,仅供参考]
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Digital signal processor with high speed arithmetic and logic operation is the base for its digital realization. In this paper, it introduces the principle of direct torque control and the character of TMS320LF2407 digital signal processor. At the same time, it gives the software and hardware design of direct torque control system for asynchronous-motor based on the TMS320LF2407 DSP.
本文介绍了直接转矩控制的基本原理及TMS320LF2407 DSP的特点,给出了以TMS320LF2407 DSP为核心的异步电动机直接转矩控制系统的设计方案及软硬件的实现,同时对直接转矩控制系统进行了实验和仿真,验证了直接转矩控制技术的优良性能。
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Calculated results showed that in the Ni2MnIn phase, the atomic orbital magnetic moment of Mn dominates the unit cell's magnetic moment, i. e., about 85% of the total magnetic moments of unit cells. The contribution of Ni to the total cell's magnetic moments is about 15%. As to the In atoms, they show a weak diamagnetism in both phases. In particular, the phase transformation of tetragonal martensite results in the decrease in Fermi energy of Ni2MnIn unit cells by 0.495 eV.
计算表明:四方马氏体相变导致Ni2MnIn元胞费米能下降0.495eV;Ni2MnIn结构中,In原子具有弱抗磁性,晶胞磁矩为Mn原子轨道磁矩所主导,约占元胞总轨道磁矩85%,Ni原子轨道磁矩贡献约占元胞总轨道磁矩15%。
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Secondly, the paper is expanded from follow three aspects: the virtual design, the virtual process and the product data managementduring the developing the torque converter. Applying the key technique of concurrent engineering---design for function, design for assemblyand design for manufactureof the method of design for "X", the virtual design of the torque converter is accomplished in CATIA V5. Then the model constitution and the simulation of virtual process of the torque converter is done in CATIA V5, including the model constitution and the simulation of 5-aixe NC virtual process of the vane, the model constitution(material:PVC) of the idler pulley rapid prototypingand the virtual assembly and the motion simulation of the torque converter, etc. 3-D data exchange between various CAD systems is realized by using STEP standard. The lever of classing the character model of the torque converter is given. And the access authorization is set up and given to manage the partners' reading/writing the product data.
应用并行工程的关键技术之一——面向产品全生命周期的设计DFX中面向功能的设计DFF、面向装配的设计DFA和面向制造的设计DFM的方法,在CATIA V5中完成液力变矩器虚拟设计;在CATIA V5中对液力变矩器进行虚拟加工建模和仿真,包括液力变矩器导轮叶片五轴数控加工刀轨建模与仿真、导轮快速成型RP建模、液力变矩器虚拟装配和运动仿真等;采用STEP标准实现多CAD系统之间三维数据交换,提出液力变矩器特征模型的分级标准并对三维模型数据进行分级管理,制定相应的权限等级以规范合作厂家的产品数据管理层次。
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ABSTRACT Aiming at problems of trans-vector controller in a vehicle-carried induction motor such as variable rotor and stator resistance following motor temperature, and their inductance varying with flux saturation degrees. Firstly, CSI and VSI are introduced, for CSI, it can hold the advantages both FOC and DTC using stator flux directional, PI parameter and simulation are also introduced. Secondly, equations of IM in the synchronous rotary frame and its static counterpart, as figuring in the saturation condition of magnetic field, are dealt in this paper and the simulation results are presented. Thereafter, the parameter designing of PI trans-vector controller is processed, which features the non-linear model. In practical realization, as neglecting the dynamical change of motor inductance, this paper employs online modification of inductance parameters, according to the flux saturation, then transforms the non-linear equations into linear ones, and so compacts the structure of controller. Thirdly, in view of the maximum torque output is extraordinary requisite when Electrical Vehicle start up, accelerate, and overtake, this paper issues the maximum torque when both inverter and battery capacity is corporeally definite. Fourthly, on-line differentiating and analyzing both rotor's time constants and its flux by using the expanding order reduction and discrete Kalman filter equation are fathomed, in order to realize high-performance trans-vector algorithm, and also the simulation results are presented. Fifthly, the close-loop regenerative brake system, when the EV's torque is set constant, is deduced; at the same time, unification of electric drive model and brake model is executed. Combined with maximum charge current demands, the mathematical model for online yielding torque as a demand.
本论文针对车载异步电机在矢量控制器所遇到的问题:定转子电阻随温度变化及随电机饱和程度变化的转子电感及定子电感而影响电机调速性能提出一套完整的解决方案:分析了电流型逆变器和电压型逆变器在实现矢量控制时控制器参数的计算,分析出对于电流型逆变器在采用定子磁场定向时,其性能同时具有矢量控制和直接转矩控制两者的优势,并对电压型逆变器在转子磁场定向下的模型进行了仿真研究;建立异步电机非线性模型,推导出考虑磁饱和时异步电机在同步旋转坐标系及静止坐标系下的方程,并做出了仿真结果,建立异步电机在非线性模型下的矢量控制调节器的PI参数设计,在实际应用中,若忽略电机电感的动态变化,可以根据当前的磁路饱和状态而在线修正电感参数,从而将非线性方程线性化,降低控制器的复杂度;考虑到电动汽车在起动和加速超车时需要电机有最大转矩输出,本文讨论在逆变器容量一定和电池供电能力有限的情况下电机最大转矩输出问题;推导了异步电机扩展降阶、离散卡尔曼滤波方程在线辨识转子时间常数和转子磁通,用于实现高性能的矢量控制算法,并给出了仿真结果;推导出了电动汽车恒转矩给定的闭环回馈制动系统,实现了电动控制模型和制动模型的统一,而且结合铅酸电池最大充电电流的要求,为制动转矩在线给定建立了数学模型;设计了基于双DSP系统的高性能矢量控制器软硬件框图,并以大量实验数据说明矢量控制在电动汽车应用的实际应用状况。
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For this objection, we propose a kind of optimal interpolator in the senes of the minimizing mean square error, which using the image nonseparable autocorrelation function model and characteristic of circular quincunx interpolator's coefficient distribution. The experiments testified that the interpolating characteristic of APIDCSF is similar to the optimal interpolator. A quasi-vanishing moment curve is proposed here.
消失矩高的滤波器内插性能好于消失矩低的滤波器,或者说支撑大的滤波器内插性能好于支撑小的滤波器,对于支撑相同但消失矩不同的不同类滤波器,提出了准消失矩曲线,可以检测二维不可分离的内插滤波器的内插性能以及在相同支撑下低阶消失矩与高阶消失矩滤波器的相似度。
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The torque ripple in direct torque control system of permanent magnet synchronous motor is analyzed. To decrease the torque ripple in PMSM DTC, a PMSM DTC system based on the strategy of modulating the time of voltage vector is proposed .
讨论了永磁同步电机直接转矩控制转矩脉动问题,针对永磁同步电机直接转矩控制存在较大脉动转矩的缺点,提出了一种模糊调节电压矢量作用时间的永磁同步电机直接转矩控制策略。
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The torque ripple in SRM are relatively higher compared to induction machines. In this paper, based on the experimental data of static torque characteristic, a fuzzy-neural network is applied to learning it's inverse model off line, then according to the predefined torque distribute function, optimal current profile is real-time gained by the FNN on line, which results in a linear, decoupled, low ripple control of torque. The performances of the proposed method is demonstrated by computer simulation results.
与传统交、直流电机相比,SRM的一个最突出的缺点是其驱动系统转矩脉动比较严重,为此,论文提出了一种基于模糊神经网络转矩逆模型的SRM转矩控制方案,并设计了SRM滑模电流控制器,理论分析和仿真结果表明,基于滑模电流控制器的SRM电动机转矩逆模型控制策略能够有效的解耦、补偿和抵消SRM非线性转矩脉动特性,有效的控制SRM相转矩按期望相转矩变化,从而实现了SRM高性能、低脉动转矩控制。
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On the basis of the investigation of different moments, the concept of generalized moments is firstly defined and then, an abstract algorithm framework for computing the accurate generalized moments is presented. The framework replaces integrals on 2-dimensions space by summations on 1-dimension ORBIR list without introducing the error incurred by discrete sampling, and therefore, reduces the computation complexity for moments generation.
矩在工程实践中的应用非常广泛,在考察矩的实质的基础上,定义了泛化矩的概念,并研究泛化矩的生成框架,该框架在不引入离散化过程中存在的采样误差的前提下,将矩生成过程中需要的二重积分运算转化为在一维的ORBIR矩形序列上的求和,因此降低了矩生成的计算复杂度。
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This thesis proposed the design and implementation of an ASIC for the motor control with DTC technology. Note that this ASIC is implemented by cell-based Design style with Verilog language.The basic principle of the Direct Torque Control is to select the switch sequence of the inverter. Those switches will control the magnetism and torque of the stator, to induce a fast response of the induction motor. Furthermore, the d-q axle's static coordinate, which is transferred from both the three-phase current and voltage, is used to compute the stator's magnetism and torque. By comparing with original values, those magnetism and torque will be calculated and set to new data. Then the switching table and the hysteresis controller are decided with the new data to generate a voltage vector and to control the stator magnetism and torque.
直接转矩控制的基本原理为经由侦测马达定子磁通与转子转速,来适当的选择变频器功率电晶体的切换状态,以获得快速且不易受外在环境影响的马达控制响应;首先,根据量测三相电流与利用变频器的切换状态取得马达的三相电压,将其转换至d-q轴静止座标,然后藉此估测马达的磁通量与转矩量,再分别与侦测的定子磁通量和转矩量比较后,得到定子磁通量与转矩量比较的结果,再利用DTC电压向量切换表(DTC Voltage Vector Switching table),依定子磁通与转矩的比较值及马达所在的角度位置,来选择一个适当的电压向量,进而依切换顺序来激发功率电晶体,达到控制感应马达的目的。
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To compute moments of a twodimensional image, a large number of multiplications and additions are required in a direct approach.
它的基本思想是利用数据并行性将一个二维图像矩分解成垂直矩和水平矩,然后在LS MPP协处理器上利用级联求和算法在垂直方向和水平方向分别计算二维图象的多个垂直矩和一个水平矩。
- 推荐网络例句
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This one mode pays close attention to network credence foundation of the businessman very much.
这一模式非常关注商人的网络信用基础。
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Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.
扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。
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There is no differences of cell proliferation vitality between labeled and unlabeled NSCs.
双标记神经干细胞的增殖、分化活力与未标记神经干细胞相比无改变。