【作者】 杨志勇；

【导师】 徐建源；

【作者基本信息】 沈阳工业大学 ， 电机与电器， 2010， 硕士

【摘要】 为了满足电力网供需变化与功率平衡问题要求,电网各部分需投入或切除电力设备。但是,这些操作可能引起暂态响应并在系统内传播,不仅对断路器本身与用户设备产生危害,还会引起继电保护装置误动,甚至危及电力系统稳定,这在电能质量要求越来越严格的背景下需引起重视。同步关合技术是指断路器动、静触头在控制系统的控制下,在系统电压波形的指定相角处关合,使得空载变压器、电容器和空载线路等电力设备在对自身和系统冲击最小的情况下投入电力系统的一种智能控制技术。同步关合技术从原理上能有效地削弱断路器合闸时所产生的涌流和过电压,该技术优于合闸电阻、串联电抗器等传统方法,但其实际动作的准确性与可靠性一直是争论的焦点。因此,本文对同步关合技术做了一些研究。首先,对高压断路器的同步关合技术的核心算法即关合时间的预测算法做了一些研究,由于同步关合时间受到环境温度,控制电压、预击穿特性等外界因素的影响,所以本文根据已有10kV真空永磁断路器和145kVSF6弹簧断路器的影响因素跟关合时间关系的数据,利用MATLAB软件中的神经网络工具箱和遗传算法工具箱,研究一种遗传优化BP神经网络算法实现关合时间的预测。其次,由于背靠背换流站滤波器关合时产生的涌流是滤波器损坏的主要原因,所以本文利用电磁暂态仿真(ATP/EMTP)软件仿真分析某220kV背靠背换流站滤波器断路器采用同步关合技术对限制涌流的作用,以及研究涌流限制标准对同步关合技术预测时间的误差的要求。并对合闸过电压做了一些分析。最后,在上一章的基础上,分析预击穿对同步关合技术的影响,利用ANSYS软件计算某252kV断路器的不同间距的击穿电压与额定条件下的某合闸行程曲线结合,得出击穿电压随时间变化的曲线,与触头两端系统电压相比较,得出该条件下关合分散区间和目标关合点以及过电压的值。通过上述研究,为同步关合技术提供一些理论依据。更多还原

【Abstract】 In order to meet the requirements of balance between supply and demand changing in power grid, electrical equipments should be put on or cut off in some parts of the power grid. But these operations may leading to transient response and spread in the system, not only destroy the circuit breakers themselves and the other equipments, but also cause relay protection devices miss-operation, or even endanger the power system stability, which get more and more attentions in the background of the power quality requirements increasingly stringent.Synchronous closing technology is an intelligent control technology that the dynamic and static contacts of circuit breaker closing at the specified phase angle of the system voltage waveform under the control of the control system, in order to make no-load transformers, capacitors and load lines switch on the power system when impacts to electrical equipments and system are the minimum. The circuit breaker with synchronous closing technology can effectively reduce the inrush current and over-voltage when closing from the principle. The technology is better than closing resistor, series reactor and other traditional methods. But the actual accuracy and reliability of movement has been a bone of contention. Therefore, this article did some researches about synchronous closing technology of high voltage circuit breaker.First, This paper did some research about the closing time prediction algorithm which is the core algorithm of synchronous closing technology of high-voltage circuit breaker. Duo to the factors of pre-arcing characteristics, ambient temperature, control voltage and so on affect closing time, therefore, base on the established data of relation between closing time and effect factors of a 10 kV permanent magnet vacuum circuit breaker and a 145kV SF6 spring circuit breaker, and using the neural network and the genetic algorithm toolbox in MATLAB software, this paper studied a genetic optimizing BP neural network algorithms to forecast closing time.Second, the inrush current is the reason that the filters on back to back converter station was damaged. Therefore, using electromagnetic transient simulation(ATP/EMTP) software, this paper analyzed the effect to limiting closing inrush current when circuit breaker with synchronous technology of the filters. Base on the inrush limit standard, this paper researched the error requirements of predicting closing time. And analyzed capacitor closing over-voltage.Finally, based on the previous chapter, this paper calculated the breakdown voltages of a 252kV circuit breaker by ANSYS software. Combining the different breakdown voltages at gap distances of circuit breaker with the closing travel curve under the rated condition, the relation curve between breakdown voltage and time was obtained. And comparing the system voltage at both ends of the contacts, closing deviation and closing objective point and the over-voltage value was obtained.Through above researches, this paper provided some theories about synchronous closing technology of high voltage circuit breaker.更多还原