牵引供电系统电能质量检测系统算

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牵引供电系统电能质量检测系统

算法及实现研究

摘要

随着国民经济的发展和生产技术的不断提高，各种电器设备，特别是大功率

电力电子装置在电气化机车中使用越来越广泛，他们在电网中会产生大量的谐波

与负序污染，大量的谐波分量不仅会引起供电系统继电保护装置的误动作而引发

不同的供电事故，如不能在牵引变电站得到及时治理，将注入电力系统，影响全

网，波及一般用户，随着城铁和地铁的发展，这一矛盾日益突出。由于电气化铁

路机车沿铁路移动用电，其产生的危害性远比其它任何谐波源设备更为严重，更

为广泛。治理谐波的先决条件是对不同工况下的谐波状况进行合理监测和细致分

析，而国内绝大多数供电站段都不具有相关的分析仪器和设备。因此，根据我国

电气化铁路的自身特点，研制携带方便、分析功能强大而且符合铁路工作习惯和

要求，高性价比的、多功能、便携式谐波检测分析装置显得尤为重要。

针对牵引供电系统中会要求检测多达 16 路电压（电流）信号，谐波检测次数

最高达到 63 次谐波，而现有大多数电能质量检测设备只适用于三相四线制系统，

检测通道较少，本文以阿尔泰 16 路12 位同步采集卡 PCI2008 和FLUKE is200 电

流钳、“兵字”电压互感器为硬件基础，采用 LabVIEW 为软件平台，设计了适合

我国牵引供电系统电能质量检测与分析系统。系统对频率的测量分别采用了三点

法和线性调频变换(CZT)，发现三点法抗干扰能力较差，仅适用谐波含量较少的

系统中，本文对三点法的误差进行了分析，得出了其数学机理，并制定了相应的

抑制方案，取得了较好的应用效果；而 CZT 法虽然所需数据量较大，但精度高，

稳定性好，测量误差仅为±0.04Hz；系统对功率参数的求取分别讨论了Budeanu 理

论和Fryze 理论，并用对比传统的直角三角形法和 Hilbert 滤波法求取无功功率的

结果，直角三角形法测量的无功功率没有方向性，但其计算简单，结果稳定性好

而Hilbert 滤波法求取结果不直观；系统通过分析牵引供电系统中所采用的接线方

式，推导出不同接线方式下一次侧都不存在零序电流，对称的正序电流和负序电

流可以构成封闭的三角形的特点，利用余弦定理和对称分量法求取负序电流，实

验证明，该方法具有较高精度；在对谐波与间谐波进行检测时，尝试采用现代数

字信号分析理论来进行分析，发现 Hilbert-Huang 变换检测方法，在对信号进行经

验模态分解(EMD)时，由于电压或电流信号基本分量远大于其他各次谐波分量而

导致的模态混叠，无法将各次谐波特别是高频且含量较低的谐波成分分离，虽然

相关文献提出了解决模态混叠的方法，但是算法复杂，不便于在工程实际中应用

小波函数因其时频窗口具有自适应的特点，在检测非平稳信号中得到广泛应用，

但小波变换不能如傅里叶变换那样检测到某一确定频率的谐波幅值和相位，另外

在试验中，信号重构时产生的小波混叠现象比较严重，分解出的谐波分量含有其

他次谐波，小波函数的作用是作为带通滤波器使用的，使得分解后的信号有不同

程度的衰减，实际应用中必须解决好小波混叠和信号衰减问题；系统还根据实际

需要，实现了对故障前 10 个周波，故障后时间可调的故障录波功能；利用

LabVIEW 和Access 数据库技术实现了牵引变电所参数的修改、增加、删除功能，

电能质量测量参数、谐波与间谐波参数的 95%概率统计分析功能，并对分析统计

结果生成报表文件。目前该系统在北京铁路局石家庄供电段的京广线、石太客专和

石德线上运行，系统功能正常，得到铁路工作人员的首肯。

关键词：电能质量牵引供电系统谐波检测小波分析软锁相

LabVIEW

Abstract

With the development of national economy and the continuous improvement of

production technology, all kinds of electrical equipment, especially high-power power

electronic devices used in electric locomotive more and more widely, they would lead a

lot of harmonics and negative sequence polluting the power network. A large number of

harmonic components would lead to power system relay protection device malfunction,

and then they caused the different power supply incidents. If they can not receive timely

treatment in the traction substation, they would be injected into the power system and

affect the whole network, spread to the general user. With the the development of the

suburban railway and subway, this contradiction is increasingly prominent. As the

electric railway locomotive moving along the railway, producing harmonic is more

serious and more widespread than any other harmonic source. The prerequisite for

harmonic filtering solution is rational harmonic condition monitoring and careful

analysis under different conditions. majorities of the power stations do not have related

analytical instruments and equipment. Thus, according to its own characteristics of our

Railway Electrification, developing a harmonic detection device of portable, powerful

and, cost-effective, versatile, consistent of the railway work habits and requirements is

very important.

Traction power supply system required testing up to 16 voltage (current) signal and

harmonic detection of up to 63 times, while the majority of power quality testing

equipments available are applicable to the three-phase four-wire system, less testing

channels. This paper designed an electric traction power supply system for China

Quality Inspection and analysis system, using Art 16-way 12-bit simultaneous

acquisition card PCI2008 and FLUKE is200 current clamp, "Bingzi" voltage

transformer as the hardware basis, LabVIEW as the software platform. Frequency

measurement system used three-point algorithm and chirp Z transform (CZT), finding

that three-point algorithm has poor anti-interference ability. it was only fit for systems

with less harmonic content. The paper deduced the mathematical mechanism of three-

point algorithm frequency measurement error. Based on the mechanism, it got the

optimal sampling point interval when error was the minimum. Finally, through the least

square method to fit phase angle between two sample points Although CZT algorithm

required the amount of data, but its high accuracy, good stability and measurement error

is only ± 0.04Hz. System calculating power parameters discussed Budeanu theory and

Fryze theory. Comparing the traditional method of right angled triangle with Hilbert

filter method, found that the result of reactive power calculating by right triangle

method is without direction, but its calculation is simple, stable. the result of Hilbert

filter method is not intuitive. Through analyzing the wiring way in traction power

supply system, deduced that the mode of connection does not produce zero sequence

current in the primary side. Symmetric positive sequence current and negative sequence

current can constitute a closed triangle, and use law of cosines and symmetry to obtain

the negative sequence current, experimental results show that the method has high

accuracy. In the harmonic and inter-harmonic detection, the paper attempt to use

modern digital signal analysis theory to the analysis, found that when using Hilbert-

Huang transform to detect the harmonic, dispose the signal with empirical mode

decomposition (EMD), as the basic component of voltage or current signal is much

larger than the other harmonic components, that caused mode mixing, can not separate

the harmonics specilly the high-frequency harmonic components. Although the

literature suggested some solutions to discrease the effection, computational complexity

make it not easily applied in engineering practice. Wavelet function, the time-frequency

window is adaptive, is widely used in detecting non-stationary signals field. But wavelet

transform can’t detect a defined frequency harmonic amplitude and phase like Fourier

transformation. In the test, when the signal reconstruction generated the wavelet aliasing

much serious. the harmonic decomposed contained the other harmonics. The wavelet

function was used as a bandpass filter, making the decomposed signal have different

levels of attenuation. The practical application must resolve wavelet aliasing and signal

degradation. System based on actual needs, achieving the function of recording the 10

waves before the fault, and time adjustable after fault. Use LabVIEW and Access

database technology to achieve the function of the traction substation parameters

modifing, adding, deleting, 95% probability of power quality measurement parameters,

harmonic and inter-harmonic parameters statistical analysis, and generated report file

about analysis results. The system currently is running in the Beijing-Guangzhou line,

Shijiazhuang-Taiyuan passenger dedicated line and shijiazhuang-dezhou line in

Shijiazhuang Section of Beijing Railway Bureau power supply section. System is

running normal and received well.

Key words: power quality, traction power supply system, harmonic

detection, wavelet analysis, Soft Lock, LabVIEW

目录
中文摘要
Abstract
第一章 绪论......................................................................................................................1
§1.1 电能质量的基本问题...........................................................................................1
§1.2  电能质量分析的国内外现状..............................................................................3
§1.2.1 频率...............................................................................................................3
§1.2.2 无功功率.......................................................................................................4
§1.2.3 负序...............................................................................................................4
§1.2.4 谐波...............................................................................................................5
§1.2.5 间谐波...........................................................................................................8
§1.2.6 国内外现有产品对比...................................................................................9
§1.3  课题来源及研究意义..........................................................................................9
§1.4  论文的研究任务及创新点................................................................................10
第二章  牵引供电系统的构成及特点...........................................................................13
§2.1  牵引供电系统的构成........................................................................................13
§2.2  牵引网的供电方式与供电回路........................................................................14
§2.3  北京路局下属部分站段供电结构特点............................................................16
第三章  牵引供电中电能质量分析的研究...................................................................18
§3.1  频率测量............................................................................................................18
§3.1.1 基于线性调频变换(CZT)的频率测量.......................................................18
§3.1.2 三点法测频率.............................................................................................19
§3.1.3 三点法误差分析与抑制.............................................................................19
§3.2 无功功率的测量.................................................................................................23
§3.2.1  直角三角形法............................................................................................24
§3.2.2  Hilbert 滤波法............................................................................................25
§3.3  负序电流的测量................................................................................................26
§3.3.1  负序电流的通用表达式............................................................................26
§3.3.2  在不同接线方式下负序电流的计算........................................................26
§3.4  谐波算法的研究................................................................................................30
§3.4.1  基于傅立叶变换的谐波分析....................................................................31
§3.4.2  基于 Hilbert-Huang 变换理论的谐波分析...............................................33
§3.4.3  基于小波分析的谐波检测........................................................................35
§3.5 本章小结.............................................................................................................41
第四章  牵引供电电能质量分析系统设计...................................................................42
§4.1  电能质量分析系统的各项指标及要求...........................................................42
§4.2  系统硬件的设计...............................................................................................43
§4.3  系统软件的设计...............................................................................................44
§4.3.1  LabVIEW 编程语言简介..........................................................................45
§4.3.2  电能质量分析系统的各功能模块设计....................................................45
§4.3.3 基于软锁相技术的谐波检测.....................................................................51
§4.4 本章小结............................................................................................................56

第五章  牵引供电系统电能质量分析系统的实现.......................................................57
§5.1  系统前面板功能说明.......................................................................................57
§5.2  现场实验结果...................................................................................................62
§5.2.1  京广线某变电所测试................................................................................62
§5.2.2  石太客专某变电所测试............................................................................65
§5.2.3  石德线某变电所测试................................................................................68
§5.3  现场实验结果分析...........................................................................................71
§5.4  本章小结...........................................................................................................71
第六章  结论...................................................................................................................73
附录 A 国内外主要电能质量分析仪的基本参数及性能.............................................76
附录 B..............................................................................................................................77
附录 C..............................................................................................................................79
附录 C-1 京广线某所SS 某型电力机车取流谐波含量报表...................................79
附录 C-2a 石太客专某所CRH 某型电力机车取流谐波含量报表..........................81
附录 C-2b 石太客专某所CRH 某型电力机车取流电能质量参数测量报表..........83
附录 C-3a 京广线某所CRH 某型电力机车取流谐波含量报表..............................85
附录 C-3b 石德线某所SS 某型电力机车取流时电能质量参数测量报表.............86
参考文献.........................................................................................................................90

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摘要：

牵引供电系统电能质量检测系统算法及实现研究摘要随着国民经济的发展和生产技术的不断提高，各种电器设备，特别是大功率电力电子装置在电气化机车中使用越来越广泛，他们在电网中会产生大量的谐波与负序污染，大量的谐波分量不仅会引起供电系统继电保护装置的误动作而引发不同的供电事故，如不能在牵引变电站得到及时治理，将注入电力系统，影响全网，波及一般用户，随着城铁和地铁的发展，这一矛盾日益突出。由于电气化铁路机车沿铁路移动用电，其产生的危害性远比其它任何谐波源设备更为严重，更为广泛。治理谐波的先决条件是对不同工况下的谐波状况进行合理监测和细致分析，而国内绝大多数供电站段都不具有相关的分析仪器和设备。因此，根据我...

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