电抗

In this paper the reason of rapid increase of single phase short circuit current in 500 kV substation is analyzed. Through the calculation it is proved that neutral grounding by small reactance is an effective measure to reduce the single phase short circuit current, and the calculation method of the zero\|sequence reactance after autotransformer neutral grounding by small reactance being applied is expounded.

文中研究了500kV变电站单相短路电流急剧增长的原因，计算了变压器中性点经小电抗接地对限制单相短路电流的作用，论证了经小电抗接地是限制单相短路电流的有效措施之一，并阐述了500kV自耦变压器中性点经小电抗接地后，其等值零序电抗的计算方法，可供工程参考。

The general analysis is focused on insulation level of the autotransformer neutraland the entrance of the autotransformer after small reactance grounding. In addition, the impedancevalue of the small reactance, the protection of the neutral and autotransformer entrance, and insulation coordination is particular discussed.

本文将对500kV 自耦变中性点由直接接地改成经小电抗接地的方式后，在多种不同的运行方式下，对其中性点、主变入口处上出现的过电压进行了详细全面的分析，并在此基础上对中性点电抗器的小电抗取值、主变中性点和主变入口处的过电压保护和绝缘配合问题进行了探讨。

The excellent agreements between simulated and measured results prove the accuracy of the established circuit model. Moreover, the varactor was added to the resonator to adjust its resonant frequency. As expected, the reactance introduced by the varactor indeed affects the net inductance and capacitance obviously. It is noted that, not only the shift with the center frequency, the inductive or capacitive of the reactance can also provide a parameter to switch its frequency toward the two directions away from the one without varactor. As a consequence, a wideband tunable band-pass filter is achieved. Although the bad quality factor with the diode strongly increases the insertion loss, this concept was proved to be available for effectively tuning the center frequency of such a class of band-pass filter.

另外，在共振器上的varactor是用来调整共振器的共振频率，如预期的，由varactor所造成的电抗确实的影响到共振器的总电感和电容值，值得一提的是，不仅滤波器的中心频率可以被改变，这电抗是电感性或是电容性也将决定滤波器的中心频率将大於或小於未加varactor时滤波器的中心频率，利用这个结果，我们也实现了一个宽的可调频率带通滤波器，虽然不理想之二极体的Q值增加了滤波器的介入损失，但这原理是被证明可有效的用於调变带通滤波器的中心频率。

Following formula calculates the inductive reactance of an ideal inductor (i.e., one with no losses) to a sinusoidal AC signal.

包括电感的电抗，下列的方程式用来计算一理想电感在一正弦波交流讯号下的电抗

A non-linear reactance model and an electric principle diagram of power supply for the 90tCONSTEEL EAF at SISG are constructed,based on the data on-site gathered with the furnace,and thus a more rational power supply curve is worked out.

根据现场实测数据，确定韶钢90 tCONSTEEL电弧炉的非线性电抗模型和电气圆图，从而制定了较合理的供电曲线。文中着重讨论了建立电弧炉电抗模型的原则、方法及其对制定合理供电曲线的作用

The reactance is an important parameter in designing products, whose calculation result must be accurate enough.

电抗是产品要求和设计中的重要参数，电抗计算值必须具有足够的精确度。

When the power system load in a small disturbance, the system itself to maintain the stability of the power transmission capacity, the use of automatic excitation regulator device may reduce the reactance of the generator, and then further to maintain the transformer high-voltage bus voltage constant, so compensation not only its own reactor, but also compensation for the step-up transformer reactance, thus greatly improving the power limits of generators, which greatly increased the static stability of power system.

当电力系统的负载发生微小的扰动时，系统本身保持稳定送电的能力，使用自动励磁调节装置，则可减小发电机的电抗，再进一步维持变压器高压母线的电压恒定，这样不仅完全补偿了自身的电抗，而且还补偿了升压变压器的电抗，这样就大大提高了发电机的极限功率，即大大地提高了电力系统的静态稳定。

First,it mainly utilizes analytics to deduce formula of slot leakage reactance.It considers three instances,including monolayer-slot,multilayer isometric-slot and multilayer anisometric-slot.Then,the analytics and the FEM are utilized to calculate slot leakage reactance of stator winding of prototype of Powerformer and compare their results.Second,the theory of utilitzing FEM to calculate the reactance of Powerformer is simply introduced,including stable reactance,transient and subtransient reactance.Specially,the saturated influence of the stable reactance is considered.Then, the results are analysed.Final,it mainly introduces the influence of harmonic magnetomotive force of stator winding and analyses the harmonic magnetomotive force of stator winding.

首先是用解析法推导出Powerformer定子绕组槽漏抗的计算公式，考虑了单层圆形半闭口槽、多层等半径圆形半闭口槽和多层不等半径圆形半闭口槽三种情况，并对Powerformer样机的定子绕组槽漏抗用解析法和有限元法进行了计算，并比较其结果；其次，简要介绍了有限元法计算Powerformer电抗参数的原理，包括稳态电抗、瞬态电抗和超瞬态电抗，对稳态电抗考虑饱和影响，对结果进行分析；最后，介绍定子绕组谐波磁势对电机运行性能的影响并对定子绕组谐波磁势进行了分析。

Start to regulate to equip to regulate the control electric voltage of the adjustable electricity anti- through a PLC in the process, the electricity anti- that make lets up to zeroth gradually, electrical engineering from start the appearance steady transfer the normal movement appearance to retreat the adjustable electricity bypass again a movement, the electrical engineering starts the process to complete.

起动过程中通过PLC调节装置调节可调电抗的控制电压，使之电抗逐渐减小至零，电机由起动状态平稳过渡到正常运行状态再将可调电抗旁路后退出运行，电机起动过程完成。

Then by using FEM to calculate the direct and quadrature axis magnetic fields, the steady-state reactances x〓 and x〓 are determined with definition method and vector potential method when μ〓 equals ∞ and voltage equals 0.1U〓 and U〓 respectively.

接下来，以有限元为工具，在直轴和交轴磁场下，用定义法和矢量位法，分别确定μ〓=∞、0.1U〓和U〓状态下的稳态电抗x〓和x〓以及在额定负载下确定x〓和x〓的饱和值，并研究了直、交轴间的耦合电抗以及用路的方法确定稳态电抗。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。