【作者】 张可奇；

【导师】 周腊吾；

【作者基本信息】 湖南大学 ， 电气工程， 2007， 硕士

【摘要】 配电网中性点采用消弧线圈接地的运行方式，对改善电网供电质量、提高供电可靠性和保证整个系统安全运行具有十分重要的意义。目前国内外研究的消弧线圈，都是针对容性无功电流补偿设计的，不能补偿单相接地故障电流中的有功电流。在实际应用中，具有正常绝缘水平的电缆网络，流过单相接地故障点的接地泄漏电导电流通常为接地电容电流的2％～4％，可以不考虑零序有功电流的影响，但当绝缘老化后，该泄漏电导电流值可达到接地电容电流的10％。由于电缆的接地电容电流很大，所以，这部分接地泄漏电导电流的绝对值也是必须考虑的。因此，本文在总结国内外消弧线圈的研究成果的基础上，提出了一种基于可控电抗器原理的新型消弧线圈方案，从理论和Matlab／Simulink仿真上论证了这种消弧线圈原理的正确性。首先，文中建立了双绕组与多绕组变压器的端口模型，通过其模型分别阐述了双绕组电抗器与多绕组大容量电抗器的实现原理。然后，在多绕组电抗器原理的基础上，详细推导和分析了新型自动跟踪补偿消弧线圈的实现原理。同时针对本文消弧线圈的结构，对基于注入信号法的电网对地电容电流检测原理进行了详细推导。其次，对新型自动跟踪补偿消弧线圈的控制策略进行研究，结合本文新型消弧线圈全桥逆变器结构，分析了当前应用最广泛的滞环电流控制、三角波比较电流控制和周期采样法电流控制技术，利用Matlab／Simulink分别对其进行仿真，找出其中电流跟踪控制规律，同时给出了滞后移相控制电路的设计方案。最后，用Matlab／Simulink对新型消弧线圈系统进行建模仿真，证实了本文提出的新型自动跟踪补偿消弧线圈原理的正确性，即能同时实现补偿流经单相接地故障点的接地电容电流和接地泄漏电导电流。与此同时也验证了采用周期采样法电流控制技术跟踪一次侧绕组电流的控制方案的有效性。更多还原

【Abstract】 The Arc-suppression coil grounding manner of the distribution network is vital to the quality and reliability of the power supply, and it increases the security of the circulating network.The recent researches on arc-suppression coil at home and aboard are based on the compensation for the reactive currents, can not compensate for the active current in the single grounding fault current.In practical application, the grounding leakage conductance current of the cable network at the normal insulation has as 2 to 4 percents as that of the grounding capacitive current when it passes the single grounding fault point ignoring the influence of the zero-sequence active current. When the insulation system goes to ageing, the grounding leakage conduction current can amount to as 10 percents as that of the grounding capacitive current. The grounding capacitive current being too huge, the consideration of the absolute value of this part is necessitated.Utilizing the former research on the arc-suppression coil, this paper puts forward a new formula of the arc-suppression coil based on the principle of the controllable reactor, and verifies the validity of this new arc-suppression coil theoretically and in Matlab/Simulink simulation.Firstly, the port models of double-winding and multi-winding transformer is built and the practical principles of the double-winding reactor and multi-winding large-capacity reactor are discussed respectively. Then, the practical principle of the new arc- suppression coil with the function of auto-tracking and auto-compensating is derived and analyzed in detail. Simultaneously for the structure of arc-suppression coil in this paper, the principle of the grounding leaking conduction current based on poured into the signal method is derived exactly.Secondly, the controlling methods of the new arc-suppression coil with the function of auto-tracking and auto-compensating is studied. Combined with the whole-bridge converter of the structure of the new arc suppression, the hysteresis current control, the triangular-wave comparative current control and the current control technology in weekly sampling are analyzed. Simulated the above-mentioned technologies in the way of Matlab/Simulink respectively, the following and controlling rules of currents are figured out and the designing schemes of the hysteresis phase shift control current is put forward.Finally, the new arc-suppression coil system is modeled and simulated in Matlab/Simulink, and the validity of the principles of the new arc- suppression coil with the function of auto-tracking and auto-compensating is verified, that is, it can also compensate the resistive component of the current flowing towards single-phase earth fault point except the capacitive component. And at the same time, the effectiveness of following the primary side winding currents with the technology of current controlling in weekly sampling is verified.更多还原