电压

It adopts the single chip computer control calculation meritorious service capacity, and parameters such as real power, reactive power, meritorious service rate element, tension fundamental harmonic virtual value and tension harmonious wave virtual value and so on these are separation to the calculation branch to the measurement that on the basis of the scattered integration formula in immediate future scattered Fourier transformation, the exchange basseted on to power system parameter sampling idea was achieved to adjust all the journey moreover the workmans frequency alternating current frequency and the tension virtual value as well as the electric current virtual value in the way of software .

它采用单片机的控制运算功能，根据离散积分公式即离散傅立叶变换，基于对电力系统参数进行交流采样的思想，实现同时对一路工频交流电的频率、电压有效值、电流有效值的测量，用软件计算分析出有功功率、无功功率、功率因素、电压基波有效值、电压谐波有效值等参数。

The characteristics analysis of two different current -to-voltage convertors,current transformer an reactance transformer ,shows that the current transformer has the same converting effect on the currents with different frequencies,while the reactance transformer transforms has various converting effect.

通过对电流互感器式&电流-电压&变换器和电抗变压器式&电流-电压&变换器变换特性的分析，结果表明：对于不同频率的电流，电流互感器式&电流-电压&变换器对它们的变换几乎是相同的。

The following exciting results are revealed: 1 When considering the influence of some nonlinear elements such as hard-limit of exciters, the effects of some devices such as Power System Stabilizer and Static Var Compensator which can introduce positive damping in power system, the reasonability of system parameter values in simulation, the SNB surface and HB surface on the boundary of SSSR will turn close to each other and even coalesce together; 2 Under some conditions, coupling between slow exciters and shunt capacitors will bring negative damping in power system dynamics, which increases the possibility of oscillatory instability. So the power system with mass shunt compensators is easily subjected to the oscillatory instability. In recent years, chaotic phenomena of power system have been reported many times. Some simulation studies even found chaos existing inside the power system SSSR. In this dissertation, chaotic phenomena in power systems are thoroughly studied in order to make clear the relation of chaos and SSSR. The following results are derived: 1 Based on Li-Yorke Theorem and their definition on the chaos, the existence of chaos in power system is verified; 2 Three possible routes of causing chaos in power system are found and deeply investigated. They are route of cascading period doubling, route of directly initial energizing and route of torus bifurcation (or quasi-periodicity). The latter two routes are investigated for the first time in power system stability studies; 3 When the stability conditions of chaos are broken, it is found they can lead to voltage collapse, angle divergence, or voltage collapse with angle divergence simultaneously.

针对在电力系统小扰动稳定区域内可能存在混沌吸引域的有关报道，本文深入研究了电力系统混沌现象的出现途径和与系统失稳模式之间的关系：1利用Li-Yorke定理和Li-Yorke的混沌定义，从理论上证明了电力系统混沌现象的存在性；2发现了电力系统中导致混沌出现的三种可能途径：倍周期分岔导致混沌、初始能量直接激发混沌和经由环面分岔导致混沌，并对后两种新发现的途径进行了较为细致的研究；3发现了混沌极限环破裂导致电压崩溃、角度失稳以及电压崩溃和角度失稳同时出现的现象，其中混沌极限环破裂导致系统角度失稳和电压崩溃及角度失稳同时出现的现象均属首次报道；4证明由微分-代数方程描述的系统模型，其小扰动稳定域的边界只包含HB、SNB和SIB三种分岔界面，在SSSR的内部和边界上，均不可能存在会导致混沌的点，从而将混沌现象排除在小扰动稳定域的研究之外，简化了后者的研究工作。

In the IEEE 50 generators test system, the proposed on-line voltage stability monitoring method is tested, the recursive square-root least squares filter with a forget factor is applied to track the parameters, and the results indicate that it can identify the critical bus effectively so as to realize on-line voltage stability monitoring.

将提出的电压稳定在线监测方法在IEEE 50机测试系统进行了仿真，参数辨识采用递推的带遗忘因子平方根最小二乘算法，结果表明它能有效地识别出电压稳定薄弱节点、实现电压稳定在线监测。

This paper analyzed the state of arts of the research on voltage stability for AC/DC system in detail, expecially for MIDC system.. According to the problems of voltage stability in MIDC system, the authors pointed out the issues that should be furth

本文对交直流输电系统电压稳定分析的研究现状进行了归纳和分类，介绍了用于交直流输电系统电压稳定分析的方法，特别针对多馈入交直流系统电压稳定问题，探讨了今后的研究方向。

Now most of plasma arc cutting machine by gas pressure to control flow, because when the gun aperture amount of time, the control of the gas pressure there is control of the flow.

等离子弧切割机通常有较高的空载电压和工作电压，在使用电离能高的气体如氮气、氢气或空气时，稳定等离子弧所需的电压会更高。

The influence of oscillator plate voltage, gas pressure, extraction voltage, focusing voltage and magnetic voltage on the quality of ion beam is determined and analyzed.

发现在0.6MPa以上时，N_2和CO_2的击穿电压增加趋势逐渐变缓，而混合气体的击穿电压仍呈直线增加；加入六氟化硫可明显提高绝缘性能；湿度对击穿电压影响不大。

The automatic test system for the ground cable net of missile based on database is designed.

采用单端测试法，计算机控制测试电压加载阵列并将测试电压加至被测电缆芯，依次选通各芯返回电压并与标准值比较，得出测试结果。

Double series PIN diodes operates at a hold-off voltage of 4.2 kV, and the dV/dt is promoted from 1.7 kV/ns to 2.3 kV/ns.

对于这种特殊的硅二极管结构，在它上面加一个很快的冲击电压，当冲击电压高于二极管的直流击穿电压时，二极管不会立刻击穿，会有几 ns的延迟。

Considering the shortage of voltage sensitivity in small source impedance ratio systems and with high resistance earth fault, the voltage fault component is replaced by memory voltage component to determine the fault's direction.

针对无穷大电源系统中和经高阻接地时存在的电压灵敏度不足的问题，采用保护安装处的记忆电压代替其电压故障分量，从而使保护可以可靠地判别出故障的方向。

Shop assistant: Please check at the door.

店员：请您到门口柜台交费。

In the end, transportation of PAHs in the environmental matrix was preliminarily investigated and discussed according to PAHs data of soils and sediments from a certain region in Shanghai. The result indicated that there are two or more pathways on PAHs transportation in the environmental matrix.

最后，对上海特定地区内PAHs在环境介质中的迁移径途进行了分析讨论，结果表明上海市土壤和沉积物等环境介质中PAHs的迁移存在多种途径。