故障检测

According to the analysis of reasons of transformer mal-operation in Pingdingshan Electric Power Bureac for years , and according to the present situation of transformer protection studies and applications at home and abroad. This paper points out the shortcomings of discrimination between internal faults and magnetizing inrush, the problems existing in differentiating the slight faults of turn-to-turn in transformer are also advanced. On the base of the electromagnetic characteristics of transformer, the relations between fluxional differential current and voltage of source side analyzed, all the operating states of transformer simulated by EMTP/ATP, the criterion of magnetizing inrush in transformer is got. Through the wavelet analysis of current waveform, using the intense reaction of wavelet transform to the little change of signal, the internal faults of transformer are distinguished by testing local extremum.

本文根据平顶山市电业局历年来变压器保护误动的原因分析，并根据国内外变压器保护使用和研究的现状，指出了现有变压器保护在区分变压器励磁涌流和内部故障方面以及在判断变压器匝间轻微故障方面存在的问题和不足；从变压器电磁特性出发，分析了电源侧电压和电流微分之间的关系，利用电磁暂态仿真程序对变压器各种运行状态进行了仿真，并以此建立了判断变压器是否含有励磁涌流的判据；通过对电流波形的小波分析，利用小波变换对信号微小变化极强的反映能力，通过检测电流的局部极值点来区分变压器运行状态，并作为上述判据的补充。

The paper puts forward a set of faults diagnosis methods of testing the noise of the three-phase motor current which shows the characteristics of the motor faults, and multi-varieties time series models of the noise is established, the multi-varieties residual series is changed to the monistical as the fault detection index.

提出以测试电机的三相电流噪声为电机故障特征信号的诊断方法，建立电机电流噪声多元时序模型，将时序模型的多元残差序列化为一元序列作为故障总体检测指标。

Wavelet multi-resolution analysis is applied to decompose the signal into multiple-level and the wavelet coefficient modules of its high-frequency components are obtained. The wavelet coefficient modules of a broken signal can be extracted by software demising. The threshold of demising is decided by the difference between the wavelet coefficient modules of a broken signal and those of a noise. The wavelet coefficient modules of the broken signal were shown in different levels, then the faults can be detected and distinguished by the integrated features of the variant levels' wavelet coefficient modules.

利用小波多尺度分解技术，将信号进行多尺度的小波分解，得到不同尺度下的信号高频分量的小波系数模值，并根据奇变信号和噪声信号小波系数模值的差异，采用软阈值去噪法，对其高频分量小波系数进行去噪处理，获取不同尺度上突变信号的小波系数模值，实现对故障的检测，并可根据不同尺度上小波系数模值的对应关系，实现对多重并发故障的区分。

Many of the mills and processing plants use 480 V distribution , with 2300 V for very large secondaries are often delta-connected so that plant operations may continue even if one phase becomes grounded , but these systems are always equipped with ground-indicating lights , and usually have special fault-tracing equipment so that phase-to-ground faults can be detected and isolated.

很多的纺织厂和加工厂使用480 v的分布，与2300年第五非常大的中级往往三角洲连接，使植物的行动可能会继续，即使一个阶段，成为接地，但这些系统都是配备的地面显示灯，和通常有特殊故障追踪设备，使第一阶段到接地故障可检测和孤立。

The short-circuited fault is analyzed and then the fault current is detected using lifting wavelet.

通过分析短路故障，采用提升小波对故障后的电流进行检测。

The platform of arcing experiment is composed of the arc fault generator and the current monitoring and saving unit, and several load appliances, then recommends the experimental process and the instruct of the equipments.

说明了电弧的基本性质，产生原因和故障电弧的危害，AFCI的结构和故障电弧检测的基本原理和我们研制的AFCI的技术路线。电弧试验半台由电弧发生器，录波设备和负荷设备构成。

Digital simulation for the integrated imformation transmission network of a certain power company is performed, the QoS under three configuration schemes, i.e., without QoS configuraiton, with simple differnece service configuraiton and with MPLS network configuration, are compared. Comparison resutls show that the configuration scheme of MPLS network can implement the load balance among link circuits and possesses fault self-recovery mechanism, so the failure elements can be quickly detected and the switching over of data flow among label switched paths can be realized. The fault recovery time is within miliseconds, therefore the QoS of power system realtime information can be ensured effectively and the QoS of various non-realtime information can be considered as well.

对某电力公司信息综合传输网络进行了数字仿真，比较了无服务质量配置、单纯差分服务配置和MPLS网络配置3种方案下的服务质量，结果表明：MPLS网络配置方案能够实现链路间的负载均衡，具有自愈性故障恢复机制，可以快速检测到失效元件并在多条标签交换路径之间实现数据流量的切换，故障恢复时间在毫秒级，可以有效保证电力系统实时信息的服务质量，并可同时兼顾各种非实时信息的服务质量。

In this paper,the transform of the harmonic wavelet method is applied to detect the characteristic signal components of the rotor bar broken fault.

准确检测转子断条所表现出来的故障特征，是这种故障诊断的关键。

Besides, by the application of the two kinds of similar Haar wavelet transforms, typical fault signals in power systems are analyzed. It is proved that the two kinds of similar Haar wavelet transforms are very effective methods of the detection of fault signals in power systems.

此外，本文借助于这两种相似Haar小波变换，分析了电力系统几种典型的故障信号，证明了这两种相似小波变换方法对于检测电力系统故障信号是非常有效的。

The librating diagnosis mechanism to clearance abnormity fault of engine valve is investigated,and the distilling method of chatacter parameter Eh which is high frequency energy is introduced.

对发动机气门间隙异常故障的振动诊断机理进行了研究，提出以高频能量E_h作为特征参数来检测气门间隙异常故障的方法。

They weren't aggressive, but I yelled and threw a rock in their direction to get them off the trail and away from me, just in case.

他们没有侵略性，但我大喊，并在他们的方向扔石头让他们过的线索，远离我，以防万一。

In slot 2 in your bag put wrapping paper, quantity does not matter in this case.

在你的书包里槽2把包装纸、数量无关紧要。