电压

In diagrams,such a direction is labeled either by arrows or subscripts in the symbols for voltages and is regarded to be the positive reference direction of a voltage.

In图，这个方向就是无论是箭头标记，或在电压的符号标和被认为是积极的参考方向一个电压。

The methods to achieving balanced current are presented and simulated in this paper. Thirdly, the snubbers are designed to compress the switching voltage transient. When IGBT is abruptly turned off, trapped energy in the circuit stray inductance is dissipated in IGBT, causing a voltage overshoot and damaging IGBT.

针对IGBT工作过程中出现的电压尖峰、电流尖峰和大的开关损耗问题，本文首先从理论上详细分析了IGBT逆变桥缓冲电路的工作原理，推导出缓冲电路各元件的参数计算公式，讨论了缓冲电路各元件参数对关断电压波形的影响并进行了仿真分析。

The following functions can be realized: Measuerment:the effective values of three phase current and voltage, power frequency, active power, reactive power, power factor etc. Motor control: direct starting, converse starting, star and triangle starting, self-starting. Protection:thermal overload protection, current leakage protection, open-phase protection, three-phase unbalance protection, over voltage protection, loss voltage protection, low load protection and fault warning and fault dates memory. Communication: communication of the computer in control room and the microcomputer monitor in the spots is realized by the interface of RS-485. The motor is not only controlled in the spots but also in control room. The dates, information and some functions are shared by the spots and control room too.

该电动机监控器以80C196KC单片机为核心，通过采样三相电流﹑电压信号来实现以下功能：三相电流﹑电压有效值，电网频率，有功功率，无功功率及功率因数等的测量；对电动机实现直接、正反转、星三角及自起动控制；对电动机实现热过载、漏电、断相、三相不平衡、过压、欠压及轻载保护，对故障进行报警及数据记忆；通过RS-485串行接口与中央控制室计算机实现通信功能，对电动机既可本地，也可远程控制；实现控制现场与控制室之间数据、信息、功能共享。

However, it may lead to a complex power network and a huge number of level shifters if we just set the cores to operate at their respective lowest voltage levels.

但是，假如我们将每个核心都设定在相对应的最低工作电压，这样可能会导致复杂的电压网路以及大量的电位移转器。

CJX2－d Series AC contactor is mainly used in the ciruit AC 50HZ (or-60HZ),rated insulating voltage is 380V unde AC-3 usage it can be combined with suitable thermal overload equipment into a electromagnetic starter to protect the circuit that may appear overload The comactor can be equipped with builbing block style auxiliary con tact group、air delaying contact、Interlonking mechanism and so on ac cessories to combined into time relay、reversible comtactor and star-delta starter.

CJX2-d系列交流接触器主要用于交流50HZ（或60Hz，额定绝缘电压为660V，在AC-3使用类别下额定工作电压为380V时额定工作电流至95A的电器中，供远距离接通和分断电器，并可与适当的热过载电器组成电磁起动器以保护可能发生过载负荷的电路。接触器可组装积木式辅助触头组、空气延时头、联锁机构等附件；组成延时继电器、可逆接触器、星三角起动器。

There are no significant difference in laterality and sex (χ2= 6.72p ＜0.05).The remarkable difference was between 21yearold group and other groups(χ2=8.26,χ2=12.83,p＜0.05). For those congenital blepharoptosis patients whose spike voltage is below 0.3mv, their palpebral fissure did not reach the anticipated height after the operation. On the Contrary, the patients whose spike voltage is above 0.3mv, the operative result were satisfactory.

右左眼及性别之间差异无显著意义（χ2=6.72，p＞0.05）；各年龄组间，21岁组与其前后年龄组间差异有显著意义（χ2=8.26 ，χ2=12.83，p＜0.05）；先天性上睑下垂患者峰值电压在30 mv以下者术后睑裂未达到预想高度，而峰值电压在 30 mv以上者则术后效果满意。

The automatic voltage regulator is programmed to regulate the transmission bus voltage within a reselected tolerance , despite varying transmission conditions.

自动电压调节器可在事先选定的容限范围内编程调节不同状态的输电母线电压。

Based on these, the single phase converter system is studied in detail, including the selection of the main circuit scheme, the formation of Sine-wave Pulse- width Modulation signal, the design of the drive and protection circuit of IGBT, and the design of high frequency transformer. Finally, the simulation software is employed to test the effect. And the result is satisfactory.

在此基础上，本文主要对电能质量控制稳定器所需的DC/AC控制电源进行了详细研究，包括主电路方案的选择、SPWM波的生成、IGBT的驱动和保护电路、高频变压器的设计以及闭环电压控制原理，最后进行了输出电压的计算机仿真分析，结果是令人满意的。

The thesis mainly researches on the single phase AC/AC converter in the topologies including AC_Buck and AC_Cuk. Firstly, the operating principles of the two converters are analyzed in detail and the rules of their parameters design are educed; The commutation of their power switches which is the key of these topologies to realize is analyzed in detail and a feasible solution which can be named RCD-Commutation mode is presented and proved effectual by theory analyses and simulation results.

本文首先分析了AC_Buck变换器的变换原理，得出了电路参数设计准则；继而对电路实现的难点即功率管换流问题进行了深入分析，并得出了一种可行的解决方案即RCD换流方案；作为对简单拓扑单相直接AC/AC变换器控制策略的探索，本文以AC_Buck为平台，对电压单闭环瞬时值控制方案进行了研究，在理论分析和仿真研究的基础上设计并制作了一台采用RCD换流、电压单闭环瞬时值控制的AC_Buck变换器原理样机。

At resonance the tank current is real and in phase with the coupler transformer voltage, which is in phase with the inverter voltage.

谐振时，振荡器的电流和耦合变压器的电压同相，还有逆变器的电压。

The concept of equivalent rotationally rigidity is offered and the formula of rotationally rigidity is obtained.

主要做了如下几个方面的工作：对伸臂位于顶部的单层框架—筒体模型进行分析，提出了等效转动约束的概念和转动约束刚度的表达式。

Male cats normally do not need aftercare with the exception of the night after the anesthetic.

男猫通常不需要善后除了晚上的麻醉。