查询词典 AC

Mathematical model、control method、parameter estimation and false tolerance of multiphase permanent magnet synchronous motor electric power propulsion system are studied in this thesis, with the project of "Permanent Magnet Material and 1000kW PMSM Propulsion Motor Technique" and"AC-DC-AC Electric Power Propulsion System Technique"as background, which is important national"The Ninth Five-year Plan"project studied in Advance.

本文是以国家"九五"重点预研项目"永磁材料和1000kW机电一体化永磁同步推进电机技术"为背景并结合课题"交—直—交电力推进系统技术"进行的。

In order to control the AC with the chopping method, MOSFET is used to design a pair of two-way electronic switch and an AC Buck-Boost circuit is formed.

采用MOSFET构成一对双向导电型电力电子开关，对交流电进行斩波控制，形成交流Buck-Boost电路。

Using solar cell to absorb solar energy and store into battery by DC-DC charger during daytime. When in the night, battery will be discharged to white LED by optical sensor and control circuit. Since the weather maybe cloudy or rainy, there is a spare AC power supply loop consist of transformer, bridge rectifier, filter and voltage regulator to prevent battery undercharge or circuit maintain. When the output current of battery is less than the preset value, the power source of white LED lamp will be switched over to spare AC power supply loop by the comparative and switching circuit.

用太阳能板，在日间吸收太阳光，将能源用DC-DC充电器储存於蓄电池中，夜间时由光感测控制电将蓄电池放电，提供白光LED灯所需的电源，为预防阴雨天蓄电池充电足或电故障维修，将使得灯无法点，另有市电经变压器与整稳压后之预备供电回，於蓄电池输出电低於预设值时，将白光LED灯电源换至市电预备回。

The paper introduces an underfeed winder control system mainly composed of Siemens S7-400 PLC, TP270 hand touch screen, 6SE70 AC converter. It successfully implements all AC drive control for the underfeed winder.

摘 要：介绍了由西门子S7-400 PLC、TP270触摸屏、6SE70变频器组成的下引纸复卷机的控制系统，通过公共直流母线系统和基于PROFIBUS-DP总线的分级控制的应用，实现了下引纸复卷机的全交流传动控制。

Based on the proposed ORPF models, the quadratic optimal models of minimizing the total load curtailment are established to identify power flow unsolvability for AC and AC-DC power systems, and can be further used to identify system voltage instability with the modal analysis method.

算例表明：当离散内点法不存在收敛问题时，启发式混合离散内点法能快速地获取优化解，反之，则要使用启发式混合随机优化算法来保证解的质量，但需要牺牲部分计算速度。

The dimmer control circuit comprises: three-end bidirectional controllable silicon switch element, comprising grid and turned on by trigger signal of the grid, connecting to AC power supply through lamp load; and a first variable resistor, possessing adjustable resistance and regulating lamp brightness by following modes: changing resistance value of the first variable resistor, changing phase of the trigger signal corresponding to AC voltage waveform, prolonging or shortening turning-on time bucket of three-end bidirectional controllable silicon switch element, thereby changing current provided to the lamp load.

一种调光器及调光控制电路，该调光控制电路包括：三端双向可控硅开关元件，其通过灯负载连接到交流电源，其中，三端双向可控硅开关元件具有栅极，并且由输入到所述栅极的触发信号开启；以及第一可变电阻器，其具有可调节的电阻值，其中，通过以下方式来调节灯负载的亮度：改变第一可变电阻器的电阻值，改变所述触发信号相对于交流电压波形的相位，延长或缩短所述三端双向可控硅开关元件的开启时间段，从而改变了提供给所述灯负载的电流。

The accumulated contributions of main effect QTLs for AC and PC were 35.34%, 37.33% under normal conditions and 53.40%, 58.10% under water stress condition, and the accumulated contribution of digenic epistasis for AC and PC were 66.74%, 57.49% under normal conditions and 48.65%, 36.59% under water stress conditions, respectively.

主效QTL对直链淀粉和蛋白质含量的联合贡献率在非胁迫条件下为35.34%和37.33%，在胁迫条件下分别为53.40%和58.10%；互作位点对直链淀粉和蛋白质含量的联合贡献率在正常水分条件下分别为66.74%和57.49%，在胁迫条件下分别为48.65%和36.59%。

Moreover, an experiential formula for predicting the possibilities of etch film formation in the negative half-cycle of ac has been driven from the principle of mass transfer in HCl solutions. Finally, a mechanism of ac etching for aluminum foil in HCl and a theoretical rule for choosing electroetching conditions were suggested on the results.

在此基础上，提出了铝在交流负半周发生的四种变化，以及交流腐蚀扩面机理，根据这一机理，提出了铝箔的交流腐蚀工艺优化原则，并用实验对这一原则进行了初步验证。

Compared to the control animals, the rats treated with AC showed increased levels of citrate, 2-oxoglutarate and cis -aconitate, and decreased levels of hippurate and phenylacetylglycine in the urine. Such metabolic changes may have reflected, respectively, the changes in body energy metabolism and in the metabolism of intestinal flora in response to AC treatment.

结果表明灌胃给药后代表能量代谢的柠檬酸，2-酮戊二酸（2-oxoglutarate）和顺乌火酸（ cis -aconitate），反应肠道菌群代谢状况的马尿酸盐和苯乙尿酸出现异常，并且这些变化在给药后0~8 h达到最大，16 h后基本恢复正常。

Application of SA866AE Three-phase PWM Signal Generator in AC/AC FC;2. By existing control question of mineral air compressor and power supply particularity in mine,using Mitsubishi corporation's IPM power module as main circuit component,METEL corporation's SPWM generator SA866AE as wave profile generator,a kind of transducer was designed.

针对矿用空压机控制存在的问题和矿山供电的特殊性，利用三菱公司IPM功率模块作为主电路器件，METEL公司的SPWM发生器 SA866AE 作为波形发生器，设计了一种宽输入电压范围、低成本、高可靠性的变频器，实现了矿用空压机的自动调节功能，节约了能源，提高了供气质量。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。