电源频率

The results show that the shape of meniscus is non-homogeneous because of the structure of the rectangular mold, and the height of meniscus will enlarge as increasing the power, and at the same time the meniscus fluctuate aggregately. The coil should be placed near the top of the mold and the initial free surface level should be placed in the middle of the coil in practice.

结果表明：由于矩形电磁软接触结晶器本身的结构限制，其弯月面沿周向上的分布具有不均匀性；随电源功率增大，弯月面高度增大，同时波动加剧；实际生产中线圈应尽量靠近结晶器口部位置安装，有利于提高弯月面高度和增强弯月面稳定性；浇注过程中，应该使浇注液面尽可能的控制在线圈中心偏上位置；当电源频率增大时，应该同时适当的提高电流来保证软接触效果。

The order of the factors affecting the teeming time is current intensity, frequency and diameter of the coil.

找出了可以满足出钢要求的最佳电流强度、电源频率和线圈直径参数，实验验证了电磁引流技术可以在工艺要求的条件下完成出钢。

On the basis of the studies above.the minimum power supply frequency favorable to uniform glow discharge was formulated.

在此基础上，根据大气压下有利于均匀辉光放电的放电条件，最终推算出有利于均匀辉光放电的最小电源频率。

High melt surface stability could be obtained when molten metal level is located equally with upside of induction coil.

在电源频率一定的情况下，当金属液面与线圈上平面平齐时，液面波动平缓，在施加相同功率的交变电磁场条件下所得液面形状凸起越高，是电磁铸造所要求的液面状态。

The conclusion and method are instructional to design and use of this type of sensor.

笔者从理论上分析了电源频率对差动变压器输出特性的影响，进行了实验验证，同时给出了减小这种影响的方法。1理论

Changes of the contamination of malodor caused by H_2S from municipal landfill;2. Traditional malodor control methods are limitative technically and economically.

为控制某污水处理厂恶臭的污染，介绍了采用低温等离子体技术处理恶臭气体的技术原理和电源电压、电源频率和停留时间与降解效率的关系，用低温等离子体进行了分解特征恶臭气体氨气的试验，并从工程应用和试验研究方面说明了除臭设备的电参数、工艺流程。

AC Induction Motor Control Using the constant V/f Principle and a Natural PWM Algorithm (12 pages, revision A, updated 12/05) Induction motors can only run at their rated speed when they are connected to the main power supply. This is the reason why variable frequency drives are needed to vary the rotor speed of an induction motor.

使用V/F原理的交流电机控制和简单的PWM算法（12页，修订版A，更新时间：05年12月）交流电机在连接到电源时只能以其额定速度运转，所以要改变转速必须改变电源频率。

Temperature sensors will detect and extract the air-conditioning units running process passenger compartment temperature, environmental parameters, such as temperature transmission to the PC controller Computer Control System Acquisition under the RMS parameters to be dealt with then change to provide power inverter frequency signal Electrical Power Inverter will change the frequency, the volume of gas compressor corresponding change in refrigeration was also changed.

温度传感器将检测和提取的空调机组运行过程中客室温度、环境温度等参数传输给微机控制器，微机控制系统根据采集的参数有效值进行计算处理然后向变频器提供改变电源频率的信号，变频器将电机电源频率改变后，压缩机输气量相应改变，制冷量也随之改变。

The results show that the frequency and phase position of frequency converter output power are out of phase with that of supply power, which is the main reason leading to metering system breakdown.

分析结果认为：变频器输出电源的频率和相位与供电电源频率和相位不同步是造成计量系统产生故障的主要原因。

Moreover, the electromagnetic flux density and meniscus height increase in the form of chequerboard with increasing of slit number. The numerical results can exactly illuminate some experimental phenomena, and enrich the theoretical foundation of soft-contact continuous casting technology. In practice, a softcontact mold with slit number of 16 or 24 is recommended, the suggested frequency is around 20kHz, and the slit width is about 1mm.

结果表明：钢液对结晶器内的电磁场分布有很大影响；发现了磁感应强度和弯月面高度随电源频率增加而增大的频率范围、磁感应强度和弯月面高度随切缝数目增加呈&锯齿状&增大的规律；研究结果合理地解释了一些实验现象，完善了软接触结晶器电磁连铸技术的理论基础；建议在实际应用中采用分瓣数为16或24分瓣数的结晶器，电源频率应控制在20kHz左右，切缝宽度应控制在1mm左右。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。