查询词典 power-up

A study of fault diagnosis in aircraft power system based on rough sets;2. An automatic method to measure power system harmonic;3. By using digital simulation method,this paper analyzes overvoltage of mine power system .

以煤矿井下供电系统为对象，利用数字仿真技术，通过对供电系统模型的仿真研究，探讨了各种参数对操作过电压的影响，为过电压的预防及供电安全提供了依据。

In order to optimize performances of shunt active power filter of harmonic compensation, attenuation ratio for switching ripple, stability and power losses, an improved LCL filter topology was presented based on the analysis of the frequency characteristics of the LCL filter, in which a switching-ripple shunt branch and a series-inductor were adopted to the damping resistor to reduce the power losses dramatically.

为了使并联有源滤波器谐波电流补偿性能、开关纹波衰减率、系统稳定性和功率损耗等方面性能得到系统的折中和优化，提出了一种改进型LCL滤波器拓扑，该结构充分利用了LCL滤波器的频率特性，在阻尼电阻两端引入开关纹波谐振分流支路，同时在阻尼电阻上串联一小电感，有效的减少了阻尼电阻的损耗而不改变系统的静态和动态性能。

We choose the TMS320VC5402, digital signal processor, as the computing unit, filtering the sampled signal, truncating the harmonic whose frequence greater than 2500hz, then we use the window-interpolation FFT algorithm to get the refined frequence, amplitude, phase of harmonic in sampled voltage and current, other parameter such as harmonic ratio, active power, reactive power, power factor, three-phase unbalance can be also computed base one the result of window-interpolation FFT.

选用TMS320VC5402高速数字信号处理器作为运算单元，先对采样信号进行数字滤波，去除50次以上谐波分量，然后应用加窗双峰插值FFT算法计算电压电流的各次谐波频率、幅值和相位，以及谐波含有率、有功功率、无功功率、三相不平衡度等各项电能指标，同时利用锁相环电路硬件跟踪电网频率以减小采样失步度。

In the HVDC engineering, it will produce a series of harmonic which than the fundamental frequency of power grid, and the harmonic have adverse effects with the power systems, equipment and power grids.

中文摘要：摘要：在高压直流输电工程中会产生一系列大于电网基波频率的谐波，而谐波的存在会对电力系统、设备及电网造成不良影响。

Aluminum foil in polychromatic overprinter photoelectricity scanner tracking color standard position correction and manipulation of order: first switched on automatically overprinter the total power switch device, open the channel computer power supply and track scan power, photoelectricity scanning head alignment reflector and adjust the distance from far and wide, so that the reflector to be rendered on the minimum light point, at which point the detection distance of about equal to the focal length of the photoelectricity scanning head.

铝箔众色套印洋差平电扫描器跟踪色不本场所订侧和操纵挨次为：不后不切断被迫套印安装的总电源开关，开放各通道计算机的把持电源和跟踪扫描电源，不兵平电扫描脚差准不直射不活，调度远近间隔，使不直射不活上表现的平不面最小，此时的检测间隔约即是平电扫描脚的焦距。

If reject heat is employed as useful heat, for industrial processes or district heating, the power plant is referred to as a cogeneration power plant or CHP (combined heat-and-power) plant.

如果释放的热量作为有用的热能，工业处理或区域供暖，这样的电厂被称为综合热电厂，或者成为CHP工厂。

To power grid parameter and topology error which are two main factors for the compute result of power system analysis software , research and develop the parameter identification and topology error identification system of power grid.

针对电网参数和网络拓扑影响电力系统高级应用软件计算结果的两个主要因素，以开关有功潮流估计算法和多断面参数辨识算法为核心，研究开发了电网参数辨识与实时拓扑检错系统，并在福州电网得到了应用。

For the ill conditioned load flow caused by the error produced in the transformation from electricity quantities to average power, direct current load flow and sensitivity vector are presented to find out the ill node, then by adjusting the load curve and generation curve in a certain principle, which is shown in detail with several flow charts, a new operation mode is reestablished to ensure the convergence of the calculation. Optimal multiplier method is proposed to work out the least square solution according to ill conditioned structural power network. The electricity quantities flow method enhances the reliability and accuracy of the calculation of the power transmission losses.

该方法可根据当前输电网中各个变电站24小时的电量记录，利用电量潮流计算对输电网总线损和各条线路损耗进行计算，使计算的精度满足降损措施分析和指标考核的要求；并且对于由负荷出力曲线转化成平均功率计算潮流时引入的误差，进而导致潮流计算不收敛的情况，采用直流潮流法，依据相角对有功功率的灵敏度向量判断出"网络异常点"，并且给出了解决此种情况的方法流程图；针对结构病态的电力系统潮流计算不收敛的情况，运用非线性约束优化方法中的最优乘子法求解潮流方程的最小二乘解，从而解决了电量潮流法计算理论线损时的收敛性问题，增强了该方法的适用性。

ABSTRACT With the development of modern industry, more and more production processes and assemblies (like semiconductor manufacturing, computer integrated manufacturing system and paper making, etc) rely on those equipments whose kernels are CPU chips or power electronics devices. Moreover, owing to rapid use of large numbers of nonlinear or impactive loads and various faults in power system, many power quality problems will be caused, such voltage as sag, swell, unsymmetry, flicker, fluctuation, harmonics and so on.

随着科学技术及社会文明的不断进步和发展，尤其是以信息技术为先导的知识经济时代的到来，越来越多的自动化生产设备以对电能质量十分敏感的计算机或微处理机等为核心，这就对电能质量提出了更高的要求。

This paper expounds the causes of market power, indices of market power and mitigation of market power.

然后重点研究了不同市场模式和结算方式下市场力的影响。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。