基于嵌入式微控制器的低频减载装置的研究与设计
|
摘要
电力系统稳定是电网安全运行的关键,一旦遭到破坏,必将造成巨大的经济损失和灾难性的后果。现代电力系统都是跨区域互联系统,其特征是系统规模大、超高压输电距离远,机组容量大,因此明显改善了电力系统运行的可靠性和经济性,在正常运行条件下,系统频率质量可得到显著提高。但是,系统一旦遭受大扰动,其频率稳定性有可能急剧恶化,因此在系统遭受大扰动时如何维持频率稳定以保证供电质量已成为业界普遍关注的问题。
在现代电力系统中,低频减载是保证电力系统正常运行的最后一道防线,是维持电力系统频率稳定的重要措施,无论在国内还是国外,低频减载在电力系统中都获得了广泛的应用。本文在分析国内外低频减载方案及其实现装置现状基础上,研究了电力系统的动、静态频率特性,比较了由单机带集中负荷模型得出的电力系统动态频率特性与实际电力工程系统所测量特性的不一致性,指出了用单机带集中负荷模型分析电力系统动态频率特性的局限性,对比了各种低频减载方法的优缺点,推导提出了本文所推荐的低频减载方法,设计了低频减载装置的软、硬件平台。本文完成了以下研究工作:
①分析了电力系统的动、静态频率特性,得出电力系统频率和负载与电网提供的有功功率是否平衡有关的结论,为低频减载装置设计提供了理论依据。
②提出了以系统频率及频率变化时间为减载判据构建新型低频减载装置是否减载的量化方法。
③设计了一种基于32位嵌入式微控制器MCF52235为核心的新型低频减载装置硬件平台,该平台可在以太网通信环境中使用。
④设计了一种基于“主程序+采样中断+低频减载控制中断+通信中断”构建系统软件框架的低频减载系统软件平台。从系统层次保证了系统数据采集的实时性和低频减载控制的及时性。
The electric power system stability is the key to realize power network safe operation, once the stability is damaged, it will result in huge economic losses and disastrous consequences. Modern power systems are always the cross-regional interconnected system characterized by large scale, extra high voltage, long distance and large capacity units. It has been obviously improved to the reliability and economy of power system operation. The quality of system frequency of the cross-regional interconnected system can be obviously improved generally, however, once the system is suffered from a large disturbances, the frequency stability would be deteriorated sharply, so how to maintain the frequency stability to ensure the quality of supply during the system being suffered large disturbances has been widely focused.
In the modern electric power system, under frequency load shedding is the last defense line that is used for ensuring the normal operation of electric power system, and being as the important measures to maintain the frequency stability of electric power system. Whatever at home or abroad the measures of under frequency load shedding has been widely applied in electric power system. In this paper, firstly it analyzed to the development dynamics of under frequency load shedding scheme and its device at home and abroad. Then it was studied to the dynamic/static frequency characteristics of electric power system and compared the measured frequency response characteristics of actual power system with the dynamic frequency response characteristics obtained by means of single generator with concentrated load analysis model. In the above the frequency response characteristics is different from each other, therefore there are some limitations when using single generator with concentrated load analysis model analyzes the dynamic frequency characteristics of electric power system. After that, it was made the comparison with advantages and disadvantages of various scheme of under frequency load shedding, and proposed a new scheme of under frequency load shedding. Finally it designed to the hardware system platform and software system platform. The following research works has been completed in this paper:
①Analyzed the dynamic/static frequency characteristics of electric power system. The conclusion is that the frequency of electric power system is directly related to whether or not the active load balancing with the electric power system supply. It made the substantial foundation for designing a under frequency load shedding device.
②Proposed a quantitative method of whether or not load shedding for the device of under frequency load shedding. The load shedding criterion is that it is responded to system frequency and the time of system frequency change.
③Designed a sort of new hardware platform for under frequency load shedding system. The hardware platform is based on 32-bit microcontroller MCF52235, which could be used for Ethernet communication environment.
④Designed a sort of software system platform for under frequency load shedding device. The software platform is based on the framework of“main program plus the interrupt for sampling plus the interrupt for the control of under frequency load shedding plus the interrupt for communication”. This framework could ensure the data sampling in real time and the control of under frequency load shedding in time.
在现代电力系统中,低频减载是保证电力系统正常运行的最后一道防线,是维持电力系统频率稳定的重要措施,无论在国内还是国外,低频减载在电力系统中都获得了广泛的应用。本文在分析国内外低频减载方案及其实现装置现状基础上,研究了电力系统的动、静态频率特性,比较了由单机带集中负荷模型得出的电力系统动态频率特性与实际电力工程系统所测量特性的不一致性,指出了用单机带集中负荷模型分析电力系统动态频率特性的局限性,对比了各种低频减载方法的优缺点,推导提出了本文所推荐的低频减载方法,设计了低频减载装置的软、硬件平台。本文完成了以下研究工作:
①分析了电力系统的动、静态频率特性,得出电力系统频率和负载与电网提供的有功功率是否平衡有关的结论,为低频减载装置设计提供了理论依据。
②提出了以系统频率及频率变化时间为减载判据构建新型低频减载装置是否减载的量化方法。
③设计了一种基于32位嵌入式微控制器MCF52235为核心的新型低频减载装置硬件平台,该平台可在以太网通信环境中使用。
④设计了一种基于“主程序+采样中断+低频减载控制中断+通信中断”构建系统软件框架的低频减载系统软件平台。从系统层次保证了系统数据采集的实时性和低频减载控制的及时性。
The electric power system stability is the key to realize power network safe operation, once the stability is damaged, it will result in huge economic losses and disastrous consequences. Modern power systems are always the cross-regional interconnected system characterized by large scale, extra high voltage, long distance and large capacity units. It has been obviously improved to the reliability and economy of power system operation. The quality of system frequency of the cross-regional interconnected system can be obviously improved generally, however, once the system is suffered from a large disturbances, the frequency stability would be deteriorated sharply, so how to maintain the frequency stability to ensure the quality of supply during the system being suffered large disturbances has been widely focused.
In the modern electric power system, under frequency load shedding is the last defense line that is used for ensuring the normal operation of electric power system, and being as the important measures to maintain the frequency stability of electric power system. Whatever at home or abroad the measures of under frequency load shedding has been widely applied in electric power system. In this paper, firstly it analyzed to the development dynamics of under frequency load shedding scheme and its device at home and abroad. Then it was studied to the dynamic/static frequency characteristics of electric power system and compared the measured frequency response characteristics of actual power system with the dynamic frequency response characteristics obtained by means of single generator with concentrated load analysis model. In the above the frequency response characteristics is different from each other, therefore there are some limitations when using single generator with concentrated load analysis model analyzes the dynamic frequency characteristics of electric power system. After that, it was made the comparison with advantages and disadvantages of various scheme of under frequency load shedding, and proposed a new scheme of under frequency load shedding. Finally it designed to the hardware system platform and software system platform. The following research works has been completed in this paper:
①Analyzed the dynamic/static frequency characteristics of electric power system. The conclusion is that the frequency of electric power system is directly related to whether or not the active load balancing with the electric power system supply. It made the substantial foundation for designing a under frequency load shedding device.
②Proposed a quantitative method of whether or not load shedding for the device of under frequency load shedding. The load shedding criterion is that it is responded to system frequency and the time of system frequency change.
③Designed a sort of new hardware platform for under frequency load shedding system. The hardware platform is based on 32-bit microcontroller MCF52235, which could be used for Ethernet communication environment.
④Designed a sort of software system platform for under frequency load shedding device. The software platform is based on the framework of“main program plus the interrupt for sampling plus the interrupt for the control of under frequency load shedding plus the interrupt for communication”. This framework could ensure the data sampling in real time and the control of under frequency load shedding in time.
引文
[1]王梅义,吴竞昌,蒙定中.大电网系统技术[M].北京:中国电力出版社, 1995.
[2]王锡凡.现代电力系统分析[M].北京:科学出版社, 2003.
[3]杜彦巍.提高低频减载动作速度和减载准确性的方法研究[D].重庆:重庆大学, 2006.
[4] An YW, Yung KM. Emergency control and restoration of power system under disturbance [J]. 4th International Conference on Advances in Power System Control, Operation & Management, 1997, (2): 808-812.
[5]周云海,闵勇,吴涛等.严重故障下的北京电网安全分析[J].电力系统自动化, 2002, (5): 67-70.
[6]杜奇壮.基于电力系统长期稳定的低频减载研究[D].北京:华北电力大学, 2006.
[7]徐广腾.低频减载装置研究[D].天津:天津大学, 2008.
[8]王梅义.大电网事故分析与技术应用[M].北京:中国电力出版社, 2008.
[9]国家电力监管委员会. 2005年海南电网“9.26”事故[EB/OL]. http://www.serc.gov.cn/ztzl/dlyj/dxal/200802/t20080220_6013.htm.
[10]韩英铎,闵勇,何学农等.电力系统动态频率的新概念和新算法[J].电力系统自动化, 1993, 17(10): 5-9.
[11] T.C.Yang, H.Cimen, Q.M..Zhu. Decentralised load-frequency controller design based on struetuired singular values[J]. Generation, Transmission and Distribution, IEE Proceedings, 145(1): 7-14, 1998.
[12]崔永建.微机低频减载技术研究[D].重庆:重庆大学, 2001.
[13]国家经贸委.电力系统安全稳定导则[M].北京:中国电力出版社, 2001.
[14] NERC. Planning standard[M]. 1997.
[15]前苏联动力和电气化部.电力系统稳定导则[M].苏联技术动力出版社, 1983.
[16]日本电气学会报告.电力系统稳定化技术电气学会技术报告(II部)第238号[M]. 1986.
[17]袁季修.论防止电力系统大面积停电的紧急控制措施——电力系统安全稳定运行的第三道防线[J].电网技术, 1999, 23(4): 1-4.
[18]杨博,解大,陈诚等.电力系统低频减载的现状和应用[J].华东电力, 2002, (9): 14-18.
[19] Delfino B, Massucco S, Morini A et al. Implementation and comparison of different under frequency load-shedding schemes [C]. Power Engineering Society summer Meeting, IEEE, 2001, 1: 3.7-312.
[20] W. P. Luan, M. R. Irving, J.S Daniel. Genetic Algorithm for Supply Restoration and Optimal Load Shedding in Power System Distribution Networks [J]. In IEEE Proc-Gener, Transn,Distrib, 2002, 149(2): 145-151.
[21] Matthew A. Mitchell, J. A. Pecas Lopes, et al. Using a Neural Networks to Predict the Dynamic Frequency Response of a Power System to an Under-frequency Load Shedding Scenario[J]. In power Engineering Society Summer Meeting 2000, IEEE, 2000, 1: 346-351.
[22] S.K. Tso, T.X. Zhu, Q.Y. Zeng, K.L. Lo. Evaluation of Load Shedding to Prevent Dynamic Voltage Instability based on Extended Fuzzy Reasoning [J]. In IEEE Proceeding online no.19970946: 81-86.
[23] Hsu C.-T., Kang M.-S., Chen C.-S. Design of adaptive load shedding by artificial neural networks[C]. IEEE proceedings generation, transmission and distribution. 2005, 152(3): 415-421.
[24] Mitchell M.A., Lopes J.A.P., Fidalgo J.N., et al. Using a neural network to predict the dynamic frequency response of a power system to an under-frequency load shedding scenario[C]. Power Engineering Society Summer Meeting, 2000, 1: 346-351.
[25] Lope J.A.P., Wong chan wa, Proenca L.M. Genetic algorithms in the definition of optimal load shedding strategies[C]. In PowerTech Budapest 99, International Conference on Electric Power Engineering, 1999, 154.
[26] Haidar Ahemed M.A., Mohamed Azah, AI-Dabbagh Majid, et. al. An intelligent load shedding scheme using neural networks and neural-fuzzy[J]. International Journal of Neural Systems, 2009, 19(6): 473-479.
[27]王丽君.基于多机模型的低频减载在线优化整定研究[D].沈阳:沈阳工业大学, 2008.
[28]郭权利.低频减载装置在线整定研究[D].北京:华北电力大学, 2006.
[29]裴健.新型低频减载方案的研究[D].山东:山东大学,2005.
[30]谢大鹏.电力系统低频减载算法的研究[D].四川:西南交通大学, 2008.
[31]雷宇.现代电力系统中影响动态频率特性的因素分析[D].重庆:重庆大学, 2002.
[32]李静.基于系统频率特性的低频减载方案研究[D].北京:华北电力大学, 2008.
[33]国家电力调度通信中心.电力系统继电保护规定汇编(第二版)[M].北京:中国电力出版社,2007.
[34] H. Bevrani, G. Ledwich, J.J. Ford. On the use of df/dt in power system emergency control[C]. Power Systems Conference and Exposition, 2009, 1-6.
[35] M.M. Elkateb, M.F. Dias. New technique for adaptive-freqency load shedding suitable for industry with private generation[C]. IEEE proceedings generation, transmission and distribution. 1993, 140(5): 411-420.
[36]秦明亮.在频率紧急控制装置中扩充df/dt应用的探讨[J].电网技术, 1998, (6): 39-41.
[37]郑建爱,陆广义.电力系统运行工况对自动低频减负荷装置误动的影响[J].山西电力技术, 1998, (3): 41-43.
[38] Li Zhang, Jin Zhong. UFLS designed by using f and integrating df/dt [C]. Power Systems Conference and Exposition, 2006 IEEE PES Power System Conference and Exposition, 2006, 1840-1844.
[39]胡丽丽.嵌入式电压频率控制装置的软件研究和设计[D].湖南:湖南大学, 2007.
[40]刘发宽.嵌入式电压频率控制装置的硬件研究和设计[D].湖南:湖南大学, 2007.
[41]南瑞继保电气有限公司. RCS-994A\B\C\G型频率电压紧急控制装置技术和使用说明书[M].江苏:南京.
[42]李晶皎,王爱霞,高晓兴等. ColdFire微处理器与微控制器[M].北京:电子工业出版社, 2008.
[43]飞思卡尔半导体. MCF5223x系列产品简介[M], 2007.
[44] National Semiconductor. LM1086 1.5A Low Dropout Positive Regulators[EB/OL].2005.
[45] MCF52235 ColdFire@ Integrated Microcontroller Reference Manual. Freescale Semiconductor [M], Inc, 2007.
[46] Analog Devices. AD586 High precision 5V Reference[EB/OL]. www.ic37.com.
[47] Texas Instruments. TL082 JFET-INPUT OPERATIONAL AMPLIFIERS [EB/OL]. www.ic37.com.
[48]刘靖.电力变压器微机主保护系统的研究与设计[D].重庆:重庆大学, 2008.
[49] SEIKO EPSON CORPORATION. SED1335 Series LCD Controller ICs Technical Manual [EB/OL]. http://www.epson.co.jp, 1996.
[50]李轶群.电力系统稳定控制的工程化研究[D].北京:华北电力大学, 2003.
[51]重庆新世纪电气有限公司. EDCS-7110线路保护监控单元使用说明书V1.0[M].重庆.
[2]王锡凡.现代电力系统分析[M].北京:科学出版社, 2003.
[3]杜彦巍.提高低频减载动作速度和减载准确性的方法研究[D].重庆:重庆大学, 2006.
[4] An YW, Yung KM. Emergency control and restoration of power system under disturbance [J]. 4th International Conference on Advances in Power System Control, Operation & Management, 1997, (2): 808-812.
[5]周云海,闵勇,吴涛等.严重故障下的北京电网安全分析[J].电力系统自动化, 2002, (5): 67-70.
[6]杜奇壮.基于电力系统长期稳定的低频减载研究[D].北京:华北电力大学, 2006.
[7]徐广腾.低频减载装置研究[D].天津:天津大学, 2008.
[8]王梅义.大电网事故分析与技术应用[M].北京:中国电力出版社, 2008.
[9]国家电力监管委员会. 2005年海南电网“9.26”事故[EB/OL]. http://www.serc.gov.cn/ztzl/dlyj/dxal/200802/t20080220_6013.htm.
[10]韩英铎,闵勇,何学农等.电力系统动态频率的新概念和新算法[J].电力系统自动化, 1993, 17(10): 5-9.
[11] T.C.Yang, H.Cimen, Q.M..Zhu. Decentralised load-frequency controller design based on struetuired singular values[J]. Generation, Transmission and Distribution, IEE Proceedings, 145(1): 7-14, 1998.
[12]崔永建.微机低频减载技术研究[D].重庆:重庆大学, 2001.
[13]国家经贸委.电力系统安全稳定导则[M].北京:中国电力出版社, 2001.
[14] NERC. Planning standard[M]. 1997.
[15]前苏联动力和电气化部.电力系统稳定导则[M].苏联技术动力出版社, 1983.
[16]日本电气学会报告.电力系统稳定化技术电气学会技术报告(II部)第238号[M]. 1986.
[17]袁季修.论防止电力系统大面积停电的紧急控制措施——电力系统安全稳定运行的第三道防线[J].电网技术, 1999, 23(4): 1-4.
[18]杨博,解大,陈诚等.电力系统低频减载的现状和应用[J].华东电力, 2002, (9): 14-18.
[19] Delfino B, Massucco S, Morini A et al. Implementation and comparison of different under frequency load-shedding schemes [C]. Power Engineering Society summer Meeting, IEEE, 2001, 1: 3.7-312.
[20] W. P. Luan, M. R. Irving, J.S Daniel. Genetic Algorithm for Supply Restoration and Optimal Load Shedding in Power System Distribution Networks [J]. In IEEE Proc-Gener, Transn,Distrib, 2002, 149(2): 145-151.
[21] Matthew A. Mitchell, J. A. Pecas Lopes, et al. Using a Neural Networks to Predict the Dynamic Frequency Response of a Power System to an Under-frequency Load Shedding Scenario[J]. In power Engineering Society Summer Meeting 2000, IEEE, 2000, 1: 346-351.
[22] S.K. Tso, T.X. Zhu, Q.Y. Zeng, K.L. Lo. Evaluation of Load Shedding to Prevent Dynamic Voltage Instability based on Extended Fuzzy Reasoning [J]. In IEEE Proceeding online no.19970946: 81-86.
[23] Hsu C.-T., Kang M.-S., Chen C.-S. Design of adaptive load shedding by artificial neural networks[C]. IEEE proceedings generation, transmission and distribution. 2005, 152(3): 415-421.
[24] Mitchell M.A., Lopes J.A.P., Fidalgo J.N., et al. Using a neural network to predict the dynamic frequency response of a power system to an under-frequency load shedding scenario[C]. Power Engineering Society Summer Meeting, 2000, 1: 346-351.
[25] Lope J.A.P., Wong chan wa, Proenca L.M. Genetic algorithms in the definition of optimal load shedding strategies[C]. In PowerTech Budapest 99, International Conference on Electric Power Engineering, 1999, 154.
[26] Haidar Ahemed M.A., Mohamed Azah, AI-Dabbagh Majid, et. al. An intelligent load shedding scheme using neural networks and neural-fuzzy[J]. International Journal of Neural Systems, 2009, 19(6): 473-479.
[27]王丽君.基于多机模型的低频减载在线优化整定研究[D].沈阳:沈阳工业大学, 2008.
[28]郭权利.低频减载装置在线整定研究[D].北京:华北电力大学, 2006.
[29]裴健.新型低频减载方案的研究[D].山东:山东大学,2005.
[30]谢大鹏.电力系统低频减载算法的研究[D].四川:西南交通大学, 2008.
[31]雷宇.现代电力系统中影响动态频率特性的因素分析[D].重庆:重庆大学, 2002.
[32]李静.基于系统频率特性的低频减载方案研究[D].北京:华北电力大学, 2008.
[33]国家电力调度通信中心.电力系统继电保护规定汇编(第二版)[M].北京:中国电力出版社,2007.
[34] H. Bevrani, G. Ledwich, J.J. Ford. On the use of df/dt in power system emergency control[C]. Power Systems Conference and Exposition, 2009, 1-6.
[35] M.M. Elkateb, M.F. Dias. New technique for adaptive-freqency load shedding suitable for industry with private generation[C]. IEEE proceedings generation, transmission and distribution. 1993, 140(5): 411-420.
[36]秦明亮.在频率紧急控制装置中扩充df/dt应用的探讨[J].电网技术, 1998, (6): 39-41.
[37]郑建爱,陆广义.电力系统运行工况对自动低频减负荷装置误动的影响[J].山西电力技术, 1998, (3): 41-43.
[38] Li Zhang, Jin Zhong. UFLS designed by using f and integrating df/dt [C]. Power Systems Conference and Exposition, 2006 IEEE PES Power System Conference and Exposition, 2006, 1840-1844.
[39]胡丽丽.嵌入式电压频率控制装置的软件研究和设计[D].湖南:湖南大学, 2007.
[40]刘发宽.嵌入式电压频率控制装置的硬件研究和设计[D].湖南:湖南大学, 2007.
[41]南瑞继保电气有限公司. RCS-994A\B\C\G型频率电压紧急控制装置技术和使用说明书[M].江苏:南京.
[42]李晶皎,王爱霞,高晓兴等. ColdFire微处理器与微控制器[M].北京:电子工业出版社, 2008.
[43]飞思卡尔半导体. MCF5223x系列产品简介[M], 2007.
[44] National Semiconductor. LM1086 1.5A Low Dropout Positive Regulators[EB/OL].2005.
[45] MCF52235 ColdFire@ Integrated Microcontroller Reference Manual. Freescale Semiconductor [M], Inc, 2007.
[46] Analog Devices. AD586 High precision 5V Reference[EB/OL]. www.ic37.com.
[47] Texas Instruments. TL082 JFET-INPUT OPERATIONAL AMPLIFIERS [EB/OL]. www.ic37.com.
[48]刘靖.电力变压器微机主保护系统的研究与设计[D].重庆:重庆大学, 2008.
[49] SEIKO EPSON CORPORATION. SED1335 Series LCD Controller ICs Technical Manual [EB/OL]. http://www.epson.co.jp, 1996.
[50]李轶群.电力系统稳定控制的工程化研究[D].北京:华北电力大学, 2003.
[51]重庆新世纪电气有限公司. EDCS-7110线路保护监控单元使用说明书V1.0[M].重庆.