【作者】 刘和平；

【导师】 叶一麟；

【作者基本信息】 重庆大学 ， 电气工程， 2004， 博士

【摘要】 论文详细分析了配电网消弧线圈接地系统的现状后，提出了一种新型快速可调消弧线圈接地系统和接地选线保护方法，以解决现有的消弧线圈不能快速调节和接地选线保护方法不可靠的主要问题，论文从理论分析、仿真建模分析、挂网运行试验等方面对所提出的系统和方法进行了验证。论文的主要成果如下： 论文提出的消弧线圈接地系统采用相控方式实现其电感量的快速调节，从理论上分析了这种调节方式存在的电流谐波问题，详细讨论了其产生的电流谐波与消弧线圈调节范围的关系，在此基础上提出了分段调节的方式。采用分段调节方式，可以保证在电流谐波不超限的情况下扩大消弧线圈的调节范围，而不需要专用的滤波装置。论文从理论上分析了这种分段调节方式的可行性。在理论分析所得结论指导下设计制造出了消弧线圈，该消弧线圈具有调节速度快、连续调节、调节控制准确、不需滤波装置、使用低耐压晶闸管等特点。其研究成果已获得专利。 论文首次将SABER仿真软件引入到消弧线圈设计中，其中所采用的磁路模型、线圈模型不仅能描述消弧线圈的电气特征，还能反映消弧线圈铁心和线圈的空间几何结构、使用材料参数等物理特征。这种新设计方法直观简便、精度高、提供的设计参数全面，很好地解决了在电力系统中使用电磁元件和电力电子器件的仿真难题。为大功率电磁元件设计和应用探索了一条新途径。 利用消弧线圈的快速调节功能，本论文提出了一种新的控制方法，它摒弃了现有消弧线圈接地系统使用的预调谐方法，即配电网正常运行时预先调节消弧线圈在全补偿状态的方法。新的控制方法为：当配电网正常运行时，提高过补偿或欠补偿度来抑制系统串联谐振过电压；当配电网发生单相接地故障时，迅速调节消弧线圈电感使系统发生谐振以使配电网接地点的电孤熄灭。实践证明这种新型的控制方法是有效性的。该方法去掉了现有消弧线圈接地系统为抑制中性点位移过电压而设置的并联或串联电阻，根除了电阻带来的诸多问题。 利用新型快速可调消弧线圈的控制特点，论文提出并实现了一种新型的单相接地故障选线保护的方法—基于零序电流变化量的选线保护原理，可以达到很高的准确性和可靠性，比较理想地解决了现有消弧线圈接地系统难以实现接地故障选线保护这个老大难问题。 论文还讨论了单相接地故障判据、在线检测电网对地电容电流、新型消弧线圈接地系统的计算机控制系统设计等问题。该系统经挂网运行，情况良好。可以预重庆大学博士论文见这种新型快速可调消弧线圈接地系统在我国城网改造中有着广阔的应用前景。更多还原

【Abstract】 After analyzing the current states of the arc-suppression-coil (ASC) grounding system in the distribution networks in detail, the thesis presents a novel fast adjustable ASC system and a novel protection principle about selecting single-phase ground fault line in order to solve the dominating problems that the inductance of the existing ASC is not able to change quickly and the existing method about the selecting fault line is not greatly reliable. The ASC system and methods proposed in this thesis are correct because they are verified with the theoretical analysis, the simulation and experiment results. The primary achievements in the thesis are in the following:The thyristor phase-controlled mode is employed to make the fast adjustment of the inductance of the proposed ASC. However, the current of the ASC is distorted in the mode. The thesis analyses the relation of the distorted degree of the current to the change range of the inductance in detail. The novel adjustment mode, called the section adjustment mode (SAM), is presented. The SAM is adopted to increase the change range of the ASC inductance and to make the degree of the distorted current under the expected level without the designed filters. After theoretical analyzing in detail the conclusion is made in the thesis that the SAM is realizable. Under the guidance of the theoretical results the ASC system is designed and manufactured successfully. Without the designed filters the ACS system, comprising the thyristors with lower voltage level, is adjusted in the speediness, the continuum and the exactness. The researching results have become a patent.It is the innovation that the simulation software, SABER, is employed to design the novel ASC. In the simulation designs models of the magnetic path and the coil, developed in this thesis, describe not only the inherent characteristic of the elements but also the dimension of the devices. The material amount used in the device is also evaluated. The novel design method is the excellent solution for the simulation challenge that power electrical device and the magnetic path device are applied to the power system since it’s the intuitionistic, effective and exactable. This method is also the innovation for the design and the application of the power electromagnetism device.According to the fast adjustable characteristic of the ASC system, the thesis creates a novel control method, which produces the fact that the existing control mode of the ASC systems that the distribution networks operate next to the resonant point is to beabandoned. The contents of the novel control method are in the following. When the system is in normal operation, in order to restrain the series resonant over-voltage, the inductance of the ASC is adjusted to the value that increases the over-compensation or under-compensation level. When the single-phase ground fault occurs, in order to extinguish Ihe arc, the inductance is adjusted rapidly to the value that causes the resonance. In the practice, the novel method is effective. In the novel method, the parallel or series resistors being employed for the over-voltage avoidance at the neutral point in existing ASC system are omitted, which solves many problems from the resistors.According to the fast adjustable characteristic of the ASC system, this thesis presents the novel method for the selection of the single-phase ground fault line in the network, in which the changes of zero-sequence currents of lines are employed to select the fault line. The novel method is also adopted in the proposed ASC systems. In practice, the fault line is chosen correctly by means of the novel method. The problem of the selection of the single-phase ground fault line in the existing ASC system has been solved successfully.Problems about the detection of the single-phase ground fault occurrence,the measurement of the line-to-ground capacitance and the design of the control system of the novel ASC are discussed in this thesis. The ASC system has been in operation and the behavour is good. The conclusio更多还原