查询词典 maximum extent

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。

First, the typhoon flow field is decomposed into two parts: the maximum asymmetric vortex and irrotational environmental flow field. Then the maximum asymmetric vortex is also decomposed into two parts: the maximum symmetric vortex and β-gyres. Finally, typhoon Pearl(2006) is simulated by WRF model(weather research and forcasting model), and flow fields at various times at 500hPa...

首先，将台风的流场分解成最大的、不对称的涡旋流场和无旋流场；然后将不对称的涡旋流场分解成最大的对称涡旋和不对称的β涡旋对；最后，利用WRF(weather research and forcasting)模式(V2.1.2)模拟了200601号珍珠台风，并对各时次的500hPa风场用该方法进行分解，结果表明：该方法对台风的运动机理研究和实际的台风路径预测提供了有价值的信息。

Analysis of lag correlation suggests that minimum cloud hydrometeors leads the maximum precipitation rate by 4-5 hour, and maximum cloud hydrometeors lags maximum precipitation rate by 1-2 hour.

滞后相关分析表明，降水率的峰值到来之前4-5小时云中水凝物含量最少，降水率的峰值到来之后1-2小时，云中水凝物含量最多。

The maximum likelihood function of the fatigue life was proposed based on the maximum likelihood principle, and it was born out that the maximum likelihood method could be used for the fatigue analysis.

基于极大似然原理，推导出关于疲劳寿命的极大似然函数，并证明了将极大似然方法用于疲劳分析的可行性。

A brief introduction is given to the maximum entropy method,which is based upon the maximum entropy principle and maximum likelihood principle in information theory.

最大熵法是基于信息论的最大熵原理和最大似然原理的一种方法。

A maximum method for measuring surface tension coefficient;2. A discussion on the maximum positions of a function and its transform;3. There are the minimum and the maximum of ionicity of weak acid and weak base.

在化学教学中，涉及到弱酸和弱碱的电离度，弱酸和弱碱的电离度存在极小值和极大值，用稀释定律求算电离度会引起的一定的误差。

The results show that there will be slight decrease of the control efforts when the mean absolute value or the root mean square value of the optimal control force is taken as the maximum designed control force, while the maximum control force of MR damper can be decreased by 85% compared with the maximum optimal control force. The decrease in the designed control force can not only significantly increase the capability of MR dampers, but also reduce the dimension of MR dampers for pratical application in engineering.

研究表明，当设计值取最优控制力的平均绝对值或均方根值时，MR阻尼器的最大控制力比最优控制力的最大值降低了85%，而控制效果降低不多，可以满足对结构的控制要求；降低最大控制力设计值后，不但可以充分发挥MR阻尼器的出力性能，而且可以缩小MR阻尼器的设计尺寸，便于工程应用。

These eigenvalue algorithms are examined under the mode error, i.e, the ratio of out-of-balance nodal point forces that is the difference of maximum elastic nodal point forces and maximum inertia nodal point forces, and the maximum elast...

与ANSYS的子空间迭代和Lanczos法相比，本文的子空间迭代比ANSYS的效率高很多，Lanczos法和ANSYS的效率差不多。大量较大规模的例题显示，本文对特征值算法的改进是十分有效的，算法的健壮性，通用性都达到了高水平。

The buffered-crossbar switch architecture is studied. In this paper, the maximum weight fast algorithm is used in BX, we discover the null row phenomenon in BX's maximum weight fast algorithms, and propose a doubling weight solution for null row, this promotes the performance of maximum weight fast algorithms in BX.

对缓冲Crossbar交换结构进行了研究，论文中将最大权重优先算法应用于BX结构，并对其在BX结构由于存在空列现象所导致的性能恶化提出了空列权重加倍的解决方案，提高了最大权重优先算法在不均衡负载下的性能。

Using the 294cc rotary engine, it can influence the maximum rpm and power of the engine output under the terms of using all kinds of length intake. Then it can find out the best length of intake of the rotary engine. In addition, under the terms of space limit of intake, it can influence the maximum rpm and power of the engine output when the intake is forced to limit on a certain length. To install a resonance in the intake system, according to the equation of Helmholtz, it can design the all kinds of size of the resonance. Using to change the volume and geometirc form of the resonance, it can find out the maximum rpm and horsepower of engine output in order to reduce the influence of the variation of engine intake length. Under the verification of the experimental result, this simple device can increase the rpm and horsepower of the rotary engine obviously to achieve the output performance that the engine requires to supply. Such the revisal of intake need the lower cost but it can obtain very obvious efficiency. It is a very feasible way.

藉由一具294cc的飞行器引擎，在使用各种不同长度进气道的条件下，对引擎所能输出的最大转速及马力有一定的影响，藉此找出该具引擎的最佳进气道长度；此外，在进气道因空间限制的前提下，进气道被迫只能局限某个长度以下时，在这种条件下，引擎所能输出的最大转速与马力等相关性能会随之受到影响，在进气系统加装一个共振腔，配合Helmholtz的方程式，设计出各种共振腔各部位的尺寸，利用改变共振腔的体积与几何形状，可以寻求增加引擎转速与输出马力的最大值，藉此降低进气长度变化所带来的影响，在实验结果的验证下，此一简单的装置可以明显的增加引擎转速与马力，以达到对引擎所需的输出性能要求，这样的进气系统修改所需的费用极低，但却可获得很明显的功效，是十分可行的方式。

It inculcates justification before God on the ground of human merits.

它说明在上帝灌输在地上人类优点。

TH Leaguer has excellent Quality Control and Management System.

本公司具有完善的品管部门。