电压

The features of induced withstanding voltage test and partial discharge test are introduced.

介绍了220kV变压器感应电压试验和局部放电试验的特点，通过实例分析了如何选择分接头的位置，使得试验电压既达到国家标准，又保证变压器内部不会受到过度考核。

One of these testing methods, eddy current, has been widely used for metal thickness measuring because of its good sensitivity, high test speed , non-contact and other advantage. The principle of eddy current testing is that, when the test coil is close to the metal conductor with alternating current, the eddy current would be inducing in the conductor, and correspongdingly, the eddy current would affect the original magnetic field, the result is the coils impedance and inducing voltage changed.

其中涡流无损检测技术具有灵敏度高、检测速度快、非接触等特点而广泛应用于金属厚度检测，它的原理是当载有交变电流的检测线圈靠近金属导体时在导体中产生涡流，该涡流又影响原磁场，使得线圈的阻抗和感应电压发生变化，通过分析阻抗或感应电压的变化来获得被测导体的信息。

The relations of inducing skin current of shielding layer, core voltage and core current with the environment field were obtained. The change of shield layer current wave with grounding state of external shield and core voltage with loading resistance was analyzed. According to the dependence of shield layer current oscillating frequency on electromagnetic wave propagation velocity, conception of transporting line of shield layer-ground with equivalent relative dielectric constant was presented. fited equation of equivalent relative dielectric constant with change of cable height was given.

试验得到九芯电缆屏蔽层感应电流、芯线感应电压、芯线感应电流以及环境场之间的关系；分析了皮电流波形随外皮接地状态的变化，芯电压随负载电阻的变化；基于皮电流振荡频率与电磁波传播速度的关系，提出了屏蔽层-大地"传输线"等效相对介电常数概念，给出了等效相对介电常数随电缆高度变化的拟合式；皮电流计算与测量结果在波形、振荡周期、衰减规律等方面有较好的一致性。

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。

The infeasibility degree was introduced into the mathematical model of voltage regulation, which can deal with the constraints of the model. In addition, an improved genetic algorithm was used to solve the voltage regulation problem.

在电压无功调整的数学模型中引入了不可行度概念，用于处理模型中的约束条件，并结合改进遗传机制的遗传算法对系统进行电压无功调整。

A frequency divider, comprises: an inverting unit comprising an input, and an output; and a plurality of switch inverters in series, having at least a first switch inverter and a last switch inverter; each switch inverter comprising two inphase switches, in which the first switch inverter is connected to the output of the inverting unit, and the last switch inverter is connected to the input of the inverting unit; wherein the two inphase switches of each of the switch inverters are respectively supplied by a first voltage and a second voltage, any two of the adjacent switch inverters are respectively controlled by two inverted clocks, thereby the two inphase switches are selectively turned on synchronously and turned off synchronously.

反相单元包含输入端以及输出端；串联的多个切换反相器，具有至少一第一切换反相器以及最终切换反相器，每一切换反相器包含两个同相开关，其中第一切换反相器连接于反相单元的输出端，且最终切换反相器连接于反相单元的输入端；每一切换反相器的同相开关分别由第一电压与第二电压供电，任何两个相邻的切换反相器分别受控于两个反相时钟，因此该两个同相开关是选择性同步开启及同步关闭的。

Ffset voltage at the input of an operational amplifier is comprised of two components, these components are identified in specifying the amplifier as input offset voltage and input bias current.

P的失调电压有两个主要的来源，输入偏置电流和输入失调电压。

These two pairs exhibit different offsets and bias currents, so when the applied input common-mode voltage changes, the AMPLIFIER input offset voltage and input bias current does also.

由于这两个差分对有不同的失调电流和偏置电流，因此加到输入共模电压变化，放大器的输入偏置电压和输入偏压电流也跟着改变。

Measurements from voltage sources with high internal resistance are subject to a number of errors, such as loading errors from the voltmeter's input resistance and input bias current, as well as from external shunt resistance and capacitance.

对高源内阻电压源的测量容易产生几种误差，诸如：电压表输入电阻和输入偏置电流以及外部分流电阻和电容引起的负载误差。

While the most important characteristics of the electrometer voltmeter operational amplifier are low input offset current and high input impedance, the most important requirement for the nanovoltmeter input preamplifier is low input noise voltage.

静电计电压表使用的运算放大器，最重要的特性是低输入偏置电流和高输入阻抗。纳伏表输入前置放大器的最重要的要求，则是低输入噪声电压。

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。

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。