【作者】 张素君；

【导师】 赵建军；

【作者基本信息】 河南大学 ， 控制理论与控制工程， 2007， 硕士

【摘要】 在电力系统的发、输、供过程中,电能计量尤其是高电压大容量的电能计量是非常重要的一环。计量系统发生故障,不论是自然产生还是人为造成其结果都导致计量系统不能准确计量用户所用电量。因此,研究检测故障的方法非常必要。其中,电流互感器短路(包括一、二次短路和二次相间短路)和极性反接故障以及电能表缺相故障的检测技术是当前电力计量系统的热门研究课题之一。基于这一原因,本文将电流互感器短路故障检测作为重点研究内容,主要包括:第一,提出高压电力计量系统网络故障模型。首先通过对不同负荷下计量系统电路参数的分析,得出网络阻抗与电流互感器一、二次侧短路之间的密切关系。其次,设计辅助电路,用于检测阻抗的变化,从而导出故障检测模型。最后进行了仿真研究,以证明模型对故障检测的有效性。第二,对高压计量系统的电能表缺相以及欠压故障进行分析,并分析这两种故障的几种常用检测方法。在对电流互感器二次回路相间短路和极性反接故障分析的基础上,提出根据两相电流的相位关系判断故障的检测方法,该方法不仅可以判断故障的发生而且还可以分辨故障的类型。这种方法电路简单,需要测量的参数少,简单易行。更多还原

【Abstract】 The measurement of the electric power system with high voltage and strong capacity plays an important role in the course of electric system generation, transmission and supply. The fault of measurement system, whether it is caused by nature or by human beings, can lead to the wrong measurement of the electric power which is used by users.Consequently, it is necessary to explore some methods by which the fault of the electric power measurement system can be diagnosed correctly. Among these methods is the detection technology of the the short circuit fault of the current transformer (including the short circuit of primary/secondary side, short circuit of secondary side of current transformers) and opposing connection of transformer and one or two of the three-phase voltage disconnection which are one of the hot research topics in the electric power measurement system.Based on such a reason, the detection technology of the the short circuit fault of the current transformer is taken as the main research content which is explained in details as follows:(1) A network fault model for the high voltage electric power metering system is proposed in this paper. Firstly, the closed relations between short circuit of the primary or secondary side of current transformer and the network impedance are drawn from the circuit parameter analysis of the metering system under the different loads. Secondly, an auxiliary circuit is designed, used to detect the impedance changes from which the fault model is derived. Finally, Simulations are performed on the model to demonstrate the efficiency of the fault detection model.(2) It is analyzed that one or two of the three-phase voltage disconnection and some means of detecting fault. Meanwhile, it is also analyzed that the fault of short circuit of secondary side of current transformers and opposing connection of current transformer. We can judge not only faults but also the types of the faults by use of the phase relationship of two-phase current. The detection circuit is simple, realized easily; furthermore, only two voltage values need to be measured.更多还原