查询词典 power frequency

Through analyzing, this paper points out four main methods which is used today to measure electrical power. By comparison, all of those methods can't be employed to measure audio-frequency power efficiently.

本文通过对目前电功率测量方法的分析，指出了目前电功率测量主要有四类方法；经过比较四类方法，发现都不能很好的对音频功率进行测量。

This paper presents a nonlinear robust adaptive excitation control design procedure for multi machine power systems using back-stepping method. The control objective is to drive machine power angle and frequency to the steady-state operation point, and guarantee that the close-loop system is adaptive to the uncertainties of generator damping coefficient and d-axis reactance, and robust to model errors or bounded disturbances.

利用反步法设计了多机电力系统中的非线性鲁棒自适应励磁控制方案，控制目标是调节发电机功角和频率至稳态运行点的极小领域，并使闭环系统对发电机阻尼系数和电抗参数的不确定性具有自适应能力，且对模型误差和外部有界干扰具备鲁棒性，同时保证各控制器是分散化和本地化的。

Using high-power transmission belt-driven variable frequency motor speed control, constant power and constant torque output, stable and reliable.

传送皮带驱动采用大功率变频电机调速控制，恒功率，恒扭矩输出，平稳可靠。

The mathematical model and working modes of a novel three-phase two-arm three-level neutral-point-clamped pulse width modulation rectifier suitable for direct-driving wind power system are analyzed in detail, and the constant frequency control strategies based on space voltage vectors are proposed and applied to the rectification conversion of direct-driven power generation system.

系统分析了新型三相两桥臂三电平中性点箝位脉宽调制(pulse width modulation，PWM)整流器的数学模型和工作模式，提出了基于空间电压矢量的恒频控制策略，并将其应用于直驱风力发电系统整流变换中。

In addition, by count of vibration power the influence of the vibration frequency on driving power is analysed.

通过振动装置的功率计算，分析了振动频率对驱动功率的影响。

Secondly the estimation of power spectrum of flame signal was made, and it was found to be able to reflect the stability of combustion state, which meaned that when the results of estimation of power spectrum showed that the frequency range in which the signal had certain value of energy became wider, and the peak value became larger, the extent of combustion stability became worse.

本文首次将色度学的原理引入到煤粉火焰颜色定量研究中来，试验研究发现，火焰的色度坐标可以反映火焰中风煤配比的变化：当色度坐标变小时，对应于风煤比变大，并且色度坐标对贫燃火焰反应敏感。据此可用来监视燃烧火焰中风煤配比是否失调。

Since the frequency conversion technology was adopted,the serrice power rate of shunneng garbage power plant might be controlled within 20% in the great part of time.

文章介绍了顺能垃圾发电厂变频器的选型，变频控制电路及变频调速技术的应用效果。

Then the error sources of the reaction type and electron type electric energy mete were analyzed and the theory analysis result through the concrete test have been proved. At last, the main conclusion has been drawn. When the induction type electric energy meter measures harmonics energy, the negative error characteristic appears. The higher the frequency of harmonics is, the greater the error is. The electron type electric energy meter can measure harmonics energy accurately in general cases. Except thermo-electrical conversion type electron type power meter, reaction type and electron type electric energy meter can measure direct current power.

本论文通过分析感应式和电子式电能表的工作原理推导出了电能表计量电能的数学模型；分析了感应式和电子式电能表的误差来源以及谐波对计量的影响，并通过具体的试验对理论分析结果进行了验证；得出了如下谐波对电能表计量影响的主要结论：感应式电能表计量谐波电能时，呈现负的误差特性，谐波频率越高，误差越大；电子式电能表在其频响范围内可以准确计量谐波电能。

On the basis of instantaneous forced analysis to short circuit of power transformer and numerical value calculation using low voltage impulse analysis, the paper presents the essentiality of winding distortion after short circuit of power transformer. By contrasting the three main ways of the world such as low-voltage impulse、 short circuit impedance analysis and frequency response analysis , FRA is adopted for distortion testing. Then we design a new testing instrument of transformer winding distortion—testing system of transformer winding distortion.

本文首先在对电力变压器短路时的瞬时受力分析及所受电磁力的有限元法的数值计算的基础上，论证了电力变压器短路以后进行绕组变形测试的必要性；然后通过比较的方法对目前国内外主要使用的三种方法：低压脉冲法、短路阻抗法和频率响应法，进行了一一对比，并根据对比结果，确定在本课题中使用频响法；最后在理论研究的基础上，设计出了一种新型的变压器绕组变形测试仪——电力变压器绕组变形测试系统。

The system bends down the battery module by the light, the high frequency switch incorporation inversion power source, the metering mechanism, the lightning protector and the electrical power distribution system is composed.

系统由光伏电池组件、高频开关并网逆变电源、计量装置、避雷装置及配电系统组成。

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷