摘要
过载保护技术是低压电器智能化技术的重要组成部分,广泛应用于低压断路器、过载继电器等产品中,是保证电动机、配电线路安全运行的重要技术。因此深入研究过载对电动机、配电线路运行影响的内在规律,建立适用于不同对象的过载保护模型,研究过载保护的新型数字算法,对提高过载保护的有效性具有重要意义。本文根据热平衡方程建立了以温升为变量的动态过载保护数学模型,确定了被保护对象的负载电流变化时的温升变化过程。与常用反时限保护特性相比较,此保护模型更符合负载的实际运行规律及保护要求,并对测量误差关系进行了分析。同时根据对称分量法的基本原理,提出以等效电流作为电动机热积累计算的依据的算法。
小波分析作为时频分析方法中一种新的信号处理技术,近年来取得了飞速的发展,并在各种实际工程领域中获得了广泛的应用。针对全周傅里叶算法不能滤除衰减直流分量与频率特性较差的问题,在深入研究各参数对给出的Morlet复小波幅值算法性能影响的基础上,提出减法滤波器加全周Morlet复小波幅值算法,计算配电线路的基波的幅值。它可有效滤除衰减直流分量并具有较好的频率特性与较高的计算精度。
设计了以PIC18F458单片机为核心的过载保护器硬件系统和过载保护的软件模块化系统,并通过RS-485串行口以及通信软件的设计,实现了上位机与过载保护器之间的远程双向通信。
The over-load protection technology is an indispensable constituent of the low voltage apparatus intellectualization and is widely used in the products, such as low-voltage circuit-breaker, overload relay and so on. Moreover, this technology is very important to ensure the electric motor and the distribution line safe operation. The study of inherent laws of over-load influence for the electric motor and the distribution line, building of over-load protection model for the different objects, and new digital algorithm of over-load protection is meaningful to improve the efficiency of the over-load protection validity.
This paper establishes a mathematical model for the dynamic over-load protection, based on the heat balance differential equation, to determine how temperature increases with the change of the protection object’s current. Different from the common inverse time characteristic, this model conforms to the load actual operating law and the protection request, and takes the analysis of measurement error into consideration. And, the equivalent current algorithm for the electric motor heat accumulation is proposed based on the symmetrical component method.
Wavelet analysis, as a new kind of time-frequency representation technique, has made great progress recently and been applied widely in different engineering practice. To solve the problem of the full-wave Fourier algorithm which is disable to filter decaying DC component and has worse frequency characteristic, it is presented a algorithm depending on the combination of subtraction filter and full-wave Morlet complex wavelet amplitude algorithm to get out the amplitude value of fundamental component of the current in the distribution line by studying each parameter’s influence on the performance of Morlet complex wavelet amplitude algorithm. It can filter efficiently decaying DC component, has clear frequency characteristic, and make calculation with high precision.
The hardware and software modulation systems of the intelligent over-load protector are designed with the core of microprocessor PIC18F458. Moreover the remote bi-directional communication, between superior computer and over-load protector, is achieved by the RS-485 serial communication interface and software.
引文
[1]何瑞华.我国低压电器现状及国内外发展趋势.低压电器,1998,No.3:3-8.
[2]何瑞华.我国低压电器现状及国内外发展趋势.低压电器,1998,No.4:3-10.
[3]杨国福,梁永春.低压电器发展状况及趋势.江苏电器,2004,No.4:1-4.
[4]周志敏.智能电器的现状及发展趋势.电气时空,2004,No.1:26-28.
[5]陈德桂.面向21世纪的低压电器新技术.低压电器,2001,No.1:3-8.
[6]许志红,张培铭.我国低压电器的发展与展望.电工技术杂志,2002(5):1-4.
[7]吕洪波.对微机保护使用现状的几点思考.继电器,2003,No.6:15-17.
[8]淡淑恒.智能电器综述.世界科学,2003,No.11:29-30.
[9]刘重轩.论我国电机保护的现状及未来.中小型电机,1998,No.3:53-55.
[10]戴琨.我国电机保护现状与发展趋势.2004,No.2:22-24.
[11]戚为达.国内外常见热过载继电器的对比替代与使用.电器开关,1991,No.2:17-25.
[12]钱晓龙,李鸿儒.智能电器与MicroLogix控制器.北京:机械机械工业出版社,2003.61-78.
[13]甘永梅,李庆丰,刘晓娟,等.现场总线技术及其应用.北京:机械工业出版社,2004.5-10.
[14] Rockwell Automation.E3 and E3-Plus Overload Relays User Manual,October,2001.
[15]刘逸生.介绍西门子公司电子过载继电器.机床电器,1992,No.2:38-40.
[16]李国岭.电动机保护装置及其发展趋势.电气时代,2000,No.9:30-31.
[17]万绍尤.可通信电器—DW45-630~6300型万能式断路器.电世界,2002,No.3:4-6.
[18] St. Jorgens. Optimization of AC3-liftspan with Electronic controlled Magnet System Using an Example of Contactors for Nominal Current between 185A and 820A. Proceedings of 19th International Conference on Electric Contact Phenomena, Germany, 1998: 14-17.
[19] Terry S. Davies, H. Nouri, Fred W. Briton. Towards the Control of Contact Bounce. IEEE Trans. On Component, Packaging and Manufacturing Technology-part A ,1996,Vol.19,No.3
[20] Joe Pihler, Alojz Lovreni. New Electromagnetic Contactor. Electric Power Systems Research, 2001, No.2:83-88.
[21]万绍尤. DW45-2000万能式断路器.低压电器,1998,No.5:22-26.
[22]章永孚,万绍尤,程玉彪等.万能式断路器用智能控制器软、硬件设计.低压电器.1998, No.6:19-24.
[23]蔡漩琴. DW15HH系列万能式断路器.低压电器,2000,No.5:18-20.
[24]宋锐.海格新型MC、MD系列微型断路器.低压电器,2000,No.6:11-12.
[25]章永孚,程玉彪.ST智能型脱扣器的可靠性措施.低压电器,1998,No.3:22-25.
[26]黄友民,章永孚.智能4极断路器非正常跳闸问题及其解决.低压电器,2001,No.1: 50-5l.
[27]西门子3VL系列塑料外壳式断路器.低压电器,2001,No.2:19-20.
[28]葛大麟.施耐德C65系列微型断路器.低压电器,2001,No.4:14-16.
[29]王永强.CM1L系列剩余电流保护和CM1E系列电子可调塑壳断路器.低压电器,2001,No.5: 14-17.
[30]孙书敏.小型断路器的温度补偿装置.低压电器,2001,No.5:41-42.
[31]岳大为,李奎.罗克韦尔E3-Plus智能固态过载继电器.低压电器,2005,No.5:43-48.
[32]陈德桂,低压电器技术的发展方向.电气时代,1999(10):4-6.
[33]陈德桂.低压电器最新技术发展动态.中国电工技术学会低压电器专业委员会,第十二届全国学术年会论文集,广东,2005.1.1-6.
[34] Bai-Lin Qin, Armando Guzman-Casillas.A New Method for Protection Zone Selection in Microprocessor-Based Bus Relays. IEEE Transactions on Power Delivery, 2000 , 15(3): 876-887.
[35] Li Kui, Wang Jingqin, Li Wenhua, et al.Study On Reliability for Overload Relay.1st International Conference on Reliability of Electrical Products and Electrical Contacts, China, 2004:228-232.
[36] Fujita Nobuo,Ichie Ryozo, Ogawa Shigeaki, et al. Computer-aided Protective Relay Setting System for Large Power Networks. Electrical Engineering in Japan(English Translation of Denki Gakkai Ronbunshi), 1995, 115(5):22-37.
[37] B. Kastztenny,E. Rosolowski. A Self-organizing Fuzzy Logic Based Protective Relay-An Application to Power Transformer Protection. IEEE Transactions on Power Delivery,1997,12(3):1119-1127.
[38] M. A. Manzoul. Multi-function Protective Relay on FPGA. Microelectronics and Reliability,1998, 38(12):1963-1968.
[39]徐磊,徐先勇.累加定子电流的微机型电动机过负荷保护新方案,继电器,1997 No.5:27-32.
[40] Akiyoshi Deguchi,Takaya Fujita. Development of a Design Method for a High-efficiency Water pump.JSAE Review,2000,21(l):35-39.
[41] P. Sen , Tan , K. G. John. An Integrated Probabilistic Risk Analysis Decision Support Methodology for Systems with Multiple State Variables. Reliability Engineering & System Safety, 1999. 64(1): 73-87.
[42]郎兵,李继红,周长青.电动机综合保护中过负载保护模型的研究.电力情报,1998,No.4:27-29.
[43]夏天伟,秦妙华,任继武,来常学.用于电动机过载保护的单片机保护系统研究.电气开关,2000, No.4:13-17.
[44]严支斌,尹项根,邵德军,等.新型微机反时限过流保护曲线特性及算法研究.继电器,2005,No.8:44-47.
[45] Norris Woodruff.Economical Motor Protection Using Microcomputer Technology. IEEE Transactions on Industry Application, Sep./Oct.1984:1344-1351.
[46] Everett B. Turner, H. Michael Willey. Microprocessor-based Universal Motor Protection System. IEEE Transactions on Industry Application,1981,Vol.IA-17: 1024-1029.
[47]周小丽,陈刚.反时限过流保护在微机保护装置中的实现.江苏电机工程,2003,No.5: 45-47.
[48]宋斌.具有不同特性的微机反时限过流继电器的实现.电力系统自动化,2001,No.9:57-59.
[49] Farag,A. Wael, I. Kamel Mahmoud. Microprocessor-based Protection System for Three-phase Induction Motors.Electric Machines and Power Systems,1999,27(5):453-464.
[50]孙浩波.电动机微机保护整定原则分析.上海电力,2005,No.2:213-215.
[51]张莲,邓力.异步电动机过负荷保护模型的研究.中小型电机. 2002,29(1): 25-29.
[52]邬彦辉.电机控制装置的设计.河北建筑科技学院学报, 2005年3月, Vol (1): 83-84.
[53]文尚坤,袁兆强.解微分方程算法的改进及应用研究.江西电力,2005,No.6:10-12.
[54]肖鸣.低压断路器的保护特性与电动机的过载保护.广东土木与建筑, 2005, No.4: 41-44.
[55]陈德桂.可通信低压开关电器.低压电器,1999,No.1:3-6.
[56]刘曙光.现场总线技术的进展与展望.自动化与仪表,2000,(15):1-6.
[57]戚为达.国内外常见热过载继电器的对比替代与使用.电器开关,1991,No.2:17-25.
[58] Makino,Y. Miki. Study of Operating Principles and Digital Filters for Protective Relays with Digital Computer. IEEE PES Winter Power Meeting, 1975:1821-1825.
[59] G. D. Rockefeller, E. A. Udren. High Speed Distance Relaying Using a Digital Computer Part-Ⅱ. Trans. On PAS. 1972, 91 (3):1244-1258.
[60] M. Ramamoorty. Application of Digital Computers to Power System Protections. Journal of Inst. Eng. 1972, 52 (10):235-238.
[61]洪佩孙.不对称运行与对称分量法.江苏电机工程,2002,No.5:47-50.
[62]朱东起,王岩,李发海.电机学.北京:中央广播电视大学出版社.1987.
[63]杜江,刘子胥,李晓霞.三相感应电动机断相运行分析.河北工业大学学报,2003,No.2:36-39.
[64]许志红,张培铭.智能电动机控制与保护器的研究.继电器,1998,No.6:22-27.
[65]汤蕴缪,史乃.电击学.北京:机械工业出版社,2002.140-143.
[66]夏天伟,任继武,李海波.智能脱扣器的研究.电工技术杂志,2001, No.4:23-25.
[67]赵靖英,陆俭国,王景芹,等.电子式过载保护继电器的通信接口技术.电测与仪表,2004,No.2:26-28.
[68]侯有韬,张举.一种滤除衰减直流分量的快速算法.继电器,2004,32(6):6-8.
[69] C. Hong, S. Elangovan. A B-spline Wawelet Based Fault Classification Scheme for High Speed Protection Relaying. Electric Mathines and Power Systems. 2000, 38(2): 313-324.
[70] Barbara B H. The world according to wavelets: the storey of a mathematical technique in the making,A K Peters,1998.
[71]李建平.小波分析与信号处理——理论、应用及软件实现.重庆:重庆出版社,1997.
[72] Morlet J. Wave Propagation and Sampling Theory and Complex Wave. Geophysics,1982:47(2):222-236.
[73] Ingrid Daubechies著,李建平,杨万年译.小波十讲(Ten Lectures on Wavelets).北京:国防工业出版社,2004.
[74] Mallat S. Multiresolution representation and wavelets. Ph. D. Thesis,Univ. of Pennsylvania,Philadelphia,1998.
[75] Daubechies I. Orthonormal bases of compactly supported wavelets. Comm. On Pure and Appl. Math,1988, 41(7):909-996.
[76] M. Farge, Y. Guezennee,C. M. Ho and C. Meneveau. Continuous Wavelet Analysis of Coherent Structures. Center for Turburlence Research Proceedings of the Summer Program,1990.
[77] M. Farge , et al. Wavelet Transform to Detect and Analyze Coherent Structures in Two-Dimensional Turbulent flows. Proc. Scaling Fractals and Nonlinear Variability in Geophysics II Harcelone,1989.
[78]彭玉华.小波变换在电磁场数值计算中的应用.电子学报,1996,24(12).
[79] Linjing,Qu Liangsheng. Feature Extraction Based on Morlet Wavelet and its Application for Mechanical Fault Diagnosis. Journal of Sound and Vibration,2000,23(41):135-148.
[80] Garberson H.A.Machinery. Diagnostic Application of the Morlet Wavelet Distribution. Proceeding of SPIE,2001,4389:232-242.
[81] N.G.Nikolaou,I.A. Antoniadis. Demodulation of vibration signals generated by defects in rolling element bearings using complex shifted Morlet wavelets. Mechanical Systems and Signal Processing,2005,4:1-24.
[82] H.X.Chen, Patrick S.K.Chua, G.H.Lim. Adaptive wavelet transform for vibration signal modeling and application in fault diagnosis of water hydraulic motor. Mechanical Systems and Signal Processing,2002,16(4):677-694.
[83] Wu G.P.,Huang W.Y.,Ren Z.,et al. New Method of the Generator Inter-Turn Fault Protection by Shifting–Phase Wavelet. ZhongGuo Dianji GongCheng Xuebao/Proceedings of the Chinese Society of Electrical Engineering,2001,21(6):15-18.
[84] Cheng Junsheng,Yu Dejie,Yang Yu. Application of an impulse response wavelet to fault diagnosis of rolling bearings. Mechanical Systems and Signal Processing,2005,9:1-10.
[85] Tovar-Corona B.,Hind M.D.,Torry J.N.,et al. Effects of Respiration on Heart Sounds Using Time-Frequency Analysis.Conference of Computers in Cardiology,2001,457-460.
[86] Peterson M.L.,Srinath S.,Lambert T.,et al. Wavelet Display of Dispersion in Concrete Using Paul and Morlet Wavelets. Nondestructive Testing and Evaluation,1999,15(3):151-169.
[87] Chan Y.T.,Ho K.C. Filter Design for CWT Computation Using the Shensa Algorithm. ICASSP,IEEE International Conference on Acoustics,Speech and Signal Processing-Proceedings,1999,3:1321-1324.
[88]卢新城,龚沈光,周骏,等.基于Morlet小波的高分辨率信号频谱估计.武汉理工大学学报,2002,26(5):622-624.
[89]曹豫宁,李永丽,梅云,等.基于小波变换的频谱细化方法在电动机故障检测中的应用.继电器,2002,30(6):1~3.
[90]岳林,张令弥.基于Morlet小波的信号滤波方法及在频率响应测试中的应用.数据采集与处理,2002,17(4):459-462.
[91]岳林,张令弥.脉冲激励下信号去噪新方法研究和仿真.振动工程学报,2003,16(3):335-338.
[92] Huang Shyh-Jier,Hsieh Cheng-Tao. Application of Continuous Wavelet Transform for Study of Voltage Flicker-Generated Signals. IEEE Transactions on Aerospace and Electronic Systems,2000,36(3):925-932.
[93] Liu Steven,Li Tingying,Wostenkuhler, Gerd W. Detection and Prediction of Transformer InrushSignal in Railway Applications. Proceedings of the International Conference on Systems Science,2001,3:168-175.
[94] Osofsky Samuel S. Calculation of Transient Sinusoidal Signal Amplitudes Using the Morlet Wavelet. IEEE Transactions on Signal Processing,1999,47(12):3426-3428.
[95] Agneni A. on the Use of the Gauss Filter in Modal Parameter Estimation. Mechanical Systems and Signal Processing,2000,14(2):193-204.
[96] Shensa Mark J. Discrete Inverses for Nonorthogonal Wavelet Transforms. IEEE Transactions on Signal Processing,1996,44(4):798-807.
[97]任宜春,邓寿昌,仇一颗.基于小波分析的系统识别研究.湘潭大学自然科学学报,2004,26(2):56-59.
[98]徐亚兰,陈建军,胡太彬.系统模态参数辨识的小波变换方法.西安电子科技大学学报(自然科学版),2004.31(2):281～285.
[99]胡昌华,张军波,夏军,等.基于Matlab的系统分析与设计——小波分析.西安:西安电子科技大学出版社,2000.
[100]徐长发.实用小波方法.武汉:华中科技大学出版社,2001.
[101]董长虹. Matlab小波分析工具箱原理与应用.北京:国防工业出版社,2004.
[102]刘和平,刘钊,郑群英,等.PIC18FXXX单片机程序设计及应用.北京:北京航空航天大学出版社,2005.
[103]刘和平,刘林,余红欣,等.PIC18FXXX单片机原理及接口程序设计.北京:北京航空航天大学出版社,2005.
[104]李荣正,刘启中,陈学军.PIC18FXXX单片机原理及应用(第2版).北京:北京航空航天大学出版社,2005.
[105]尉广军,郝永生,姚义.单片机系统中复位电路的可靠性分析与设计.仪器仪表学报,2002,No.3增刊:577-578.
[106]李庆波,王菽蓉,徐勇.采样计算式测量方法的特点及应用.电测与仪表,1999,No.23:4-6.
[107]张江,王诚梅.电力系统常用交流采样算法比较.山东电力技术,1999,No.1:64-66.
[108]童诗白,华成英.模拟电子技术基础(第三版).北京:高等教育出版社,2001.438-442.
[109]黄闽海.LM324四运放实用电路的设计.福建轻纺,2002,No.8:26-29.
[110]杜永泰.一种8位I/O口的单片机显示器和键盘接口.单片机与嵌入式系统应用,2002,No.12:68-69.
[111]尹天峰.键盘及其接口技术.电子世界,2002,No.8:26-29.
[112]李亚,常涛,王永强.利用74HC595实现多位LED现实的新方法.微计算机应用,2005,No.7:122-123.
[113]翟震,张春玲.用74HC595驱动LED的电路设计.机床与液压,2004,No.12:151-152.
[114]刘国勇. MAX232/MAX232A收发器及其应用.国外电子元器件,1997,No.3,28-29.
[115]刘艳玲.采用MAX232实现MCS-51单片机与PC机的通信.天津理工学院学报,1999,No.152,57-61.
[116]赵靖英.电子式过载保护继电器的智能化技术与可靠性分析.[河北工业大学博士学位论文],天津,2004.
[117]王幸之,王雷,翟成,等.单片及应用系统抗干扰技术.北京:北京航空航天大学出版社,2000.
[118]王文东,李竹林,尚建人.汇编语言与C语言的混合程序设计技术.计算机技术与发展,2006,No.8:18-20.
[119]张永,黄建宇,刘治生.C语言与编程语言混合编程的研究与实现.计算机与数字工程,2006,No.5:120-122.
[120]孙茂松.单片机在应用中的软件抗干扰技术.机床电器,2002,No.2:28-30.