查询词典 power transmission

a kind of design project of multifunction electric power quality gauged instrument based on virtual instrument is put forward in this article.this system integrates virtual instrument programming and power electronics together,to realize diverse signals of current electric power quality field allin one.the integrated signal generator unit which carries out the collection of high speed digital data,d/ a conversion and analog output in four channels,unsymmetrical synchro control fifo etc.by fpga are introduced,the flow of electric power system various signal which generates by vc programming is elaborated,and the structural design of signal amplification unit is analysed.the experiment text result shows that this gauged instrument has attained current advanced high grade of accuracy and it will accelerate the steps of electric power quality calibration because of its accuracy and versatility.

摘 要：提出一种基于虚拟仪器技术的多功能电能质量标定仪的设计方案，采用虚拟仪器编程技术和电力电子技术相结合实现集目前电能质量领域的多样信号于一体。介绍采用fpga实现高速数字量采集、d/a转换及4通道模拟量输出、非对称同步控制fifo等的集成信号发生单元，阐述利用vc编程实现的电力系统多样信号的产生流程，分析信号放大单元的结构设计。实验测试结果表明该标定仪达到目前先进的高精度等级，由于其准确性和多功能性将加快电能质量标定的步伐。

Based on varying process of generator terminal parameters after excitation fault, shortages of excitation protective principle of static stability boundary and asynchronous impedance boundary are analyzed. It proposed that excitation fault research relates to large-disturbance stability. Because dynamic power-angle character of generator after excitation fault is non-sinusoidal, there are differences between dynamic power-angle character and static state power-angle character. So it isn't ideal to protective operation result based on small-disturbance stability and static stability boundary criterion. At the same time, it proposed that asynchronous boundary impedance criterion is a constant reactive power circle moving adown j Xd′. It can ensure complete loss-of-excitation generator measuring impedance enter into the circle, but can't ensure the other condition measuring impedance including impossible losing synchronism enter. So loss-of-excitation protection would be maloperation when system voltage drops short and recovers or generator rejects load.③Based on stability principle, it puts forward setting conditions and calculation method of generator loss-of-excitation protection by direct measuring power-angle.

以励磁故障后发电机端的相关参数的变化为基础，通过对以静稳定边界和异步阻抗边界作判据的两类三种现行励磁保护在原理上存在的缺陷分析，发现：励磁故障是一个大干扰稳定性问题，励磁故障后的发电机的动态功角特性与静态功角特性有很大的差异，已远非正弦曲线，因此基于小干扰稳定性原理、以静稳定边界作判据的保护必然动作不理想；异步边界阻抗判据是一个下移j Xd′的等无功阻抗圆，它可以保证完全失磁后的发电机测量阻抗能进入该阻抗圆，但不能保证完全失磁之外的其它状态不会进入该阻抗圆，因此在系统电压短时下降或发电机突然甩负荷等情况下可能启动该保护使之误动。

Our company has established long cooperative relationship on autoignition system of boiler with many units like Xinjiang Manasi Power Plant, Huaneng Yingkou Power Plant, Xiangfan Yujiahu Thermal Power Plant, Shaanxi Pucheng Power Plant, Hubei Qingshan Power Plant, etc.

我们与新疆玛纳斯电厂，华能营口电厂，襄樊余家湖火电厂，陕西蒲城电厂，湖北青山电厂等单位在锅炉自动点火系统中有着长期的合作关系。

It transfers the slip power to mechanical power and then feed the power back to the shaft of the motor, or directly feeds the slip power to the alternating current net, so as to ensure the speed regulation a higher performance and higher power utilization ratio.

它可以把转差率转变为机械功率反馈回电动机机械轴上，或把转差功率反馈至交流电网中，使得具有良好的调速性能和较好的功率利用性。

This topic returns in view of the cut type switch spreads the type switch "to return for the predecessor design spreads the type electric power switch utilization in the LED lamps and lanterns" is the research direction, to achieve take reduces the power loss to replace the tradition operational amplifier pulse wave width accent as the goal using IC UC3842 changes part, the actuation returns spreads the type electric power switch's switch of Power MOSFET, so as to controls instead spreads the type electric power switch breakover closure's time then control voltage output size, achieves the output voltage to the load LED lamps and lanterns adjusts the LED lamps and lanterns brightness the goal.

各位大大抱歉~！因为英文底子不好！希望大家帮忙翻译一下，希望不要用翻译软体翻的最好是自己翻！拜托了！本专题针对切换式转换器的返驰式转换器为前身设计「返驰式电力转换器运用在LED灯具」为研究方向，为达到以减少功率损失为目的利用IC UC3842代替传统运算放大器脉波宽度调变部分，驱动返驰式电力转换器的Power MOSFET之开关，藉以控制反驰式电力转换器导通截止的时间进而控制电压输出的大小，输出电压至负载LED灯具达成调节LED灯具亮度的目的。

This can also be divided into two categories: one is to discuss the influence of power factor by way of dividing power circuit into capacitive and emotional under the circumstance of unchangeable voltage and frequency of output power, and the other is discussed the influence from voltage and frequency of power to power factor with the situation of constant component parameters.

具体又分为两种情况：一种是在电源的输出电压和频率都不变的条件下，把电路分为容性和感性，讨论了元件参数对功率因数的影响，另一种是讨论了在元件参数不变的条件下，电源的频率和电压对功率因数的影响。

Guangdong Cowan Power Equipment Co., Ltd. was established in 1995, the Chinese Society of the power units, the power industry standard manufacturing units developed one of the country's largest production base of power, is a professional power product research, development, production And sales of integrated high-tech enterprises in Guangdong Province.

广东科旺电源设备有限公司成立于1995年，是中国电源学会会员单位，全国电源行业制造标准拟订单位之一，全国最大电源生产基地之一，是一家专业从事电源产品研究、开发、生产、销售于一体的广东省高新技术企业。

Can be seen, no overload is the essence of the centrifugal pump, pump shaft power curve peak, or shaft power with the increase of flow rate changes are small, relatively flat power curve that axis, so that the pump shaft power in the dead lift off to zero head (that is, from zero flow to maximum flow rate) are less than equal to the original context of the supporting motive power.

可见，无过载离心泵的实质是指，泵的轴功率曲线有峰值或轴功率随流量的增加而有较小的变化，即轴功率曲线比较平坦，使泵的轴功率在关死扬程到零扬程范围内都小于等于原动机的配套功率。

This paper studies the influence of country economy guideline in power demand. According to identifying the main economy and society factors in affecting the change of Fujian power demand, the power demand forecast model is proposed. And the demand curve models fitting for diversified users are built by researching the influence of electrovalence to power demand.The influence of demand side management in load characteristic of Fujian power system is analysed.Used the arithmetic of modifying the history load curve, this paper forecast the changing and development trend of Fujian load characteristic.

本文研究了国民经济指标对电力需求的影响，通过识别影响福建省电力需求变化的主要经济社会因素，建立电力需求预测模型；研究了电价变化对电力需求的影响，对各类用户建立适合各自特点的需求曲线模型；分析了需求侧管理对福建电网负荷特性的影响，采用历史负荷曲线修正法，预测了福建电网负荷特性的变化发展趋势。

The main contents of this report include:(1) I nvestigation and analysis of the current status and characteristics of economic development, electric power consume and electric load in North China, Northeast China, Northwest China, East China, and Central China from 2000 to 2004;(2) Indexes and contrast analysis of major power networks load characteristic in China;(3) Analysis of Major effect factors for load characteristics, including development level and structure of economic, structure of electric power consumption, geographical and climatic environment, DSM, electrovalence, load shedding and so on;(4) Change trend analysis of major power networks load characteristic in China;(5) Target forecast of major power networks load characteristic in China in the tenth five-year plan;(6) Main conclusions and suggestions.

主要内容包括：(1) 2000 ～ 2004 年华北、东北、西北、华东、华中五大电网经营区域经济发展现状及特点、用电现状及特点、电力负荷特性现状调研分析；(2)我国主要电网负荷特性指标对比分析；(3)影响我国负荷特性的主要因素分析，包括经济发展水平及经济结构、用电结构、地理环境及气候因素、需求侧管理、电价拉闸限电等对电网负荷特性的影响分析；(4)我国主要电网负荷特性变化趋势分析；(5)"十一五"期间我国主要电网负荷特性指标预测；(6)主要结论及建议。

He studied their excrement for evidence of livestock hair.

他为家畜毛的证据研究他们的粪便。

Loneliness is not grounds for deportation, deportation of the people are not all lonely people.

寂寞也不是放逐的理由，放逐的人也并不都是孤独的人。