发布时间：
Welding Automation Research in the engineering school is largely focused on problems involving sensing, modeling, and control of welding processes, i.e., welding automation. Faculty and students from electrical engineering, mechanical engineering, and material science are involved in the welding automation research. The overall objective of this research is to provide both greater productivity and enhanced quality for welding in the manufacturing environment.http://eecs.vanderbilt.edu/researchgroups/weldingautomation
Control of Parallel Inverters in Distributed AC Power Systems with Consideration of Line Impedance Effect在分布式交流电力系统中考虑连线阻抗影响时的并联逆变器控制 论文发到你的邮箱了
我有一篇我本科毕设的小论文，英文中文都有，而且是我人工翻译的，8000字左右。你要的话PM我。我是电气工程及其自动化专业的。《Analysis of thyristor-controlled phase shifter applied in damping power system oscillations》
电气工程：1Electrical Engineering My decision to pursue graduate study in the United States is underscored by my desire to be a part of the graduate program at your institution. Purdue University offers the flexibility needed for such a vast and rapidly changing field. The research facilities and the faculty at the university are par excellent. Communications is an industry that has changed our lives. In a very short period it has changed the way we have looked at things since centuries. It is one industry that is going to shape our future for centuries to come. Hence my desire to do masters in electrical engineering with communications as my major. My interest in electronics blossomed during my high school years. It was the time when technology had begun to make an impact on the lives of people in India. Hence engineering with electronics as my major was the first choice for my undergraduate studies. Right since the beginning of my undergraduate study electronics is a subject that has fascinated me with its power of applications. The subjects that I have studied include Linear Electronics, Digital Electronics. These laid the foundation for my courses in Electronic Communication & Communication Systems at a later stage. My undergraduate studies already focus on the communications aspect of electronics. A masters degree in electrical engineering with communications as major field is the next logical step. For the past four months I have been working as a project trainee at the Indian Institute for Advanced Electronics. I am working on the design and development of a "PC Controlled Digital Serial Data Generator". This short stint has given me invaluable practical experience. It has given me the confidence to pursue a masters degree and also kindled a desire to do research. During the course of my work at IIAE, I have come across several scientists. Most of them work in different areas of communications. Interactions with them have made me realize the vastness and the scope of communications. My discussions with them convinced me that specializing in communications will suit me very well. The subject of research which interests me very much is spread spectrum communication systems. Coding theory and combinations is another research subject which arouses my curiosity. The subject Communication Theory which I am studying at present introduces these topics in theory. I am eager to find out more about the applications of coding theory to spread spectrum communication systems. In addition I have been a student member of the IEEE (Institute of Electrical and Electronics Engineers, Inc.) for the past three years. Through its workshops/seminars and publications like the 'The Spectrum' it has exposed me to a lot of emerging technologies in the field of communications. It is a strong belief in my family that the American education system has the best to offer in the whole world. This belief arises out of the experience that my parents had when they did their Masters of Science in the University of Pennsylvania during the years 1967-69. If I can get an opportunity to be a part of that intellectually stimulating environment, I am sure my talents will be put to optimal use. India is a developing country with an enormous potential in the information technology business. To serve the needs of this developing industry and more important its vast population, communications is going to become of utmost importance. Thus conditions here are very conducive to supplement my aspirations when I return after completing my graduate studies. 2Electrical Engineering As a graduate student, I will undertake research and coursework in Electrical Engineering to enhance my competencies in this field. I intend to complete my master's degree in order to pursue my doctorate. The research that I am most interested in pursuing at Northeastern University surrounds the optical properties of MEMS devices, and the development of substrate-based fast electro-optical interfaces. My interest in this area stems from my undergraduate study in MEMs development for tri-axial accelerometers. Engineering has been a key interest of mine since childhood. While still in grade school I enjoyed listening to my father, an electrical engineer, teach me about advances in technology, and was always eager to hear more. I was introduced to my first computer at the age of five, and have loved interacting with them ever since. My decision to study engineering as a career was no surprise to those who knew me. In college I found that I was always studying something I enjoyed. I believe it is because I enjoy my life and my work that I have been successful. Spending hours in the laboratory is not something that I dread, but instead I take pride in my work and its successful completion. One example of this that is still fresh in my mind is the successful design of a fully functional microprocessor in the Xilinx environment. All told, the project took over 150 hours of each design-team member's time. However, I did not look on it as a drain, but an experience for learning and a focus for my professional and technical development. When we finished the project we felt the sense of worth and pride in completion of a task that was once above our level of knowledge. Pursuing a graduate degree in the research field I have chosen also feels like a challenge, and I know that study will frustrate me at times. However, I feel that my commitment to learning will not be swayed. I feel confident in my ability to be creative in my perspective, and to persevere. My ultimate goal is to be an innovator in the field I have chosen to study. Professionalism and creativity are my most valued strengths. At the heart of my interest is the advancement of man in concert with his environment. My personal philosophy of life will matter greatly during my study and after its completion. That is why I devote time to reflection on my goals and their implications. Money has never been a motivator for my work, nor do I think it will be in the future. However, as a professional and a graduate, I realize that my earning potential will be significant. That is why I also commit myself to charity and fairness. In the past I have been a member of the Boy Scouts of America, and have achieved the rank of Eagle Scout. In the course of my experience in that organization, I learned respect and moral value. Now, as a member of the IEEE, I value my professional standing and its commensurate moral implications. Ethics in engineering is as important as technical skill, and as such I intend to uphold my own ethical obligations to the best of my ability. As a Northeastern University student, I would commit all that I have to offer to my study. I intend to pursue research in MEMS technology. At Rowan University as an undergraduate student I have already conducted some research and development of MEMS sensors for military applications, resulting in publication. An article, written by myself and my project member David Bowen and edited by our advisor Dr. Robert Krchnavek, was published in the NAVSEA Intelligent Ships Symposium Proceedings of 2001. The paper was titled "Designing a 3-Axis, Monolithic, MEMS-Based Accelerometer" and was under review for endorsement by the US Navy's NAVSEA facility in Philadelphia during that year. Building on my past success in MEMs design, I hope to advance my understanding. Through research at the graduate level, it is my hope to become familiar with, and innovate the design of MEMs Optics in hopes of creating a reliable and practical MEMs Electro-Optical Interface for use in consumer electronics. It is my hope, that through my research, optical waveguides for intradevice communication might be realized. Finally, my intent to pursue graduate study is laid plain. Study of MEMs optics is my intended focus, and I am committed to my goal. In pursuing a doctoral degree, I have closely analyzed myself to determine the reasons for my previous successes and my goals for the future. I have found that I do and have always enjoyed engineering, and that I have a strong desire to pursue my study further. I am prepared to commit myself to that study, and achieve what I have set out to do. 3I Wish to Pursue an MS Degree in Electrical Engineering During my senior year at Purdue University, I made a decision that has impacted the entire course of my education. While my classmates were making definite decisions about their career paths, I chose to implement a five-year plan of development and growth for myself. I designed this plan in order to examine various careers that I thought might interest me, as well as to expand upon my abilities at the time. As I was attaining a BS degree in Electrical Engineering, I decided to focus primarily on fields related to the VLSI (Very Large-Scale Integrated) circuits area. My main goals were either to gain work experience or to further my education by pursuing an MS degree in Electrical Engineering (MSEE). I saw an opportunity to both work and learn through employment at Xilinx Inc. Operating as a product engineer at a successful, high-tech semiconductor company has enabled me to utilize my technical and interpersonal skills in new and challenging ways. The position has also allowed me to interact with a multitude of departments including marketing, integrated circuit (IC) design, software/CAD development, manufacturing, reliability, accounting, and sales. I thus have gained an array of experience that extended beyond the parameters of my own responsibilities. In the workplace, I rely heavily upon the interpersonal techniques I developed as a counselor in a Purdue residence hall, as well as the organizational skills I had acquired through holding various leadership positions in cultural and engineering societies. I have also cultivated an interest in high-technology marketing that has continued to grow throughout my career. My experiences with Xilinx have heightened my hunger for knowledge in the VLSI field. Two months after joining the corporation, I applied to several part-time programs in the vicinity that would allow me to acquire an MSEE degree within two to three years. San Jose State seemed an ideal choice, for its evening MSEE courses would allow me to pursue two independent, full-time positions concurrently. The San Jose program has complimented my Xilinx duties well; both demand large levels of energy and enthusiasm while guiding me to my ultimate goal a high degree of education in VLSI sciences. The resources that I poured into both endeavors have reaped many gains. I have been promoted to a Product-Yield Engineering position within Xilinx's Coarse Grain Static Memory (CGSM) Product Engineering division. My extensive coursework plays a key role in my continued success at Xilinx. Relevant classes in advanced digital and analog VLSI design, as well as sub-micron ULSI technology, have allowed me to understand more completely the workings of Xilinx, a fab-less semiconductor company that also functions as a software and hardware design, testing, and marketing center. The gains in knowledge I have made through the combination of work experience and education have indeed been exponential. The academic records of my senior year at Purdue, coupled with my MSEE coursework, are ample proof of my dedication to learning. I feel I have overcome through hard work and dedication the brief "dry phase" I underwent at Purdue during the close of my sophomore and the first semester of my junior years. My performance at that time is in no way indicative of my usual achievements; they are instead the result of urgent family difficulties that required much foreign travel and serious attention to resolve. In May, I shall graduate with an MSEE degree from San Jose well ahead of my original estimates. This early graduation with Dean's Honors is the result of my firm belief in the value of diligence, as well as my renewed determination to strive for perfection in both work and school. I am now embarking on another five-year plan, during which I hope to fulfill several specific career goals. For instance, being part of a very dynamic and results-oriented Yield team at Xilinx calls for continuous development of computational and statistical techniques. The Yield team is divided to focus on specific process/fabrication issues and process (manufacturing) optimization. My own position is an integral part of the optimization group. Speed and cost issues continue to press high technology atmospheres towards optimization, probability and stochastic processes and systems, and rigorous simulations of mathematical models. The MS in EES&OR offered at your university will grant me the statistical knowledge that is crucial for process and production optimization in a fab-less environment. In addition, product engineering requires fundamental research on mathematical models for linear and non-linear programming, as well as the utilization of efficient computer software. I continuously employ the knowledge I gained at Purdue in Operations Research and advanced mathematics courses. Yet despite the value of these classes and my high performance in them, I now require further education to best fulfill my duties. An MS in the EES&OR field, will give me knowledge that is invaluable to a career in product development, project management and strategic planning. The program will allow me to improve decision-making skills in operations, strategy, and policy issues. I will strengthen my theory and application in countless areas:continuous, discrete, numerical optimization; probabilistic and stochastic processes; dynamic systems and simulation; economics, finance, and investment; decision analysis; dynamic programming and planning under uncertainty; operations and service; corporate and individual strategy; and private and public policy issues.Thus, the EES&OR program will not only help me to excel at Xilinx but will also further any future career. My commitment to work and education over the last three years proves that I will pursue this MS with enthusiasm and zeal.The technical edge that the MS would provide is incomparable.Since I will be working while attending Stanford, I shall mingle education with practical application, and bring to the table interesting problems from my experience and past education. Technical challenges encountered through projects in the EES&OR program will provide motivation and opportunity for methodological innovation.The data collection, processing and presentation issues presented are integral to my future goals, and the management challenges raised will provide invaluable experience for professional practice. This will in turn build a solid foundation for a life-long career that can overcome any problem in decision-making. In addition, taking courses in economics, finance, and investment analysis will allow much growth of knowledge in investment issues in different industries. The EES&OR program thus appeals not only to my engineering, economics, science and mathematical background, but will compliment my technical abilities with the conceptual frameworks needed to analyze problems in operations, production, strategic planning, and marketing in the realm of emiconductor/IC/engineering systems. I feel that I am prepared to meet the challenges of the curriculum. My coursework in intermediate microeconomics and macroeconomics, international trade, operations research, linear algebra, and probabilistic methods, along with my extensive calculus background, will allow me to function well within the program. My long-term career goals include a move into marketing and product management. I believe that attaining this MS degree is the cornerstone to achieving my goals. It will give me the academic background necessary to succeed in product development, project management, and strategic planning. It will improve decision-making skills necessary for optimizing performance. The integration of two excellent programs in Economics Systems and Operations Research thus suits my current position and ties in with future goals perfectly by improving decision making in operations, strategy and policy. At present I desire to continue at Xilinx; attending a program that provides the flexibility and convenience of the SITN, is therefore imperative. Hence, being at Stanford as an HCP student alsoattracts me. I believe that Stanford is the best environment for me to achieve my goals while gaining exposure to and experience with a diverse student body and faculty. It is my belief that one continues to learn throughout one's life, and the most effective method of learning is through interaction with others.Stanford's diversity offers an environment for learning, both inside and outside the classroom. I hope to share my varied knowledge with my classmates and to take from them a new understanding of topics that are foreign to me. I believe that no other school provides students with the combination of education and environment offered by Stanford. Its outstanding academic reputation, mingled with its diverse environment and thriving Bay Area location, creates an opportunity for growth that is second to none. I have many ambitions for myself as I embark on this stage of my life. I believe that an education from Stanford will provide invaluable experiences and skills that will allow me to become a successful and innovative business leader in the new millennium. 4Research Department of Biomedical Engineering is designed to research on and solve the bio-electrical and biomagnetic engineering problems in the field of biology and medicine with the aid of engineering principles and methods. Its main task is to explain, from perspective view of engineering, the biological and pathologic processes of the living organisms, especially human beings, and research on and develop the related medical devices and life science devices. Its research directions mainly include the modeling and emulation of the biological system, testing and analysis of biomedical signals, the biomedical imaging and processing , the biological effects of electromagnetic field and the development of artificial organs and medical devices, etc.Electromagnetic Bioengineering With the development and integration of electromagnetism, biology and medicine, biological electromagnetism exercises more and more influence on human life and health, environment protection and biological engineering. The research on electromagnetic bioengineering is a new research direction for IEECAS, mainly including research on rules of mutual influence between electromagnetic field and life matter, biological electromagnetic effect and its application in biology, medicine and medical equipment. At present, the research team has set up labs such as biological electromagnetic environment lab, biological electromagnetic signals & electromagnetic property testing lab, electromagnetic biological effect testing lab and biological electromagnetic simulation lab. It is equipped with various electrical and magnetic fields for experiments of biological electromagnetic effects, simulation software and biochemical experiment equipment. With such equipments, it can do biological electromagnetic experiments on live animals and detached live cells, detect, analyze and process the very weak biological electromagnetic signals, analyze and test live organism or detached cell under electromagnetic interaction with biochemical quantitative methods. The recent research work focuses on the effects 方向对不对，不知你要哪种，告诉我，我再接着找多的话email you
什么意思？要英文的？题目要汉语翻译？
Control of Parallel Inverters in Distributed AC Power Systems with Consideration of Line Impedance Effect在分布式交流电力系统中考虑连线阻抗影响时的并联逆变器控制 论文发到你的邮箱了
电力是发展生产和提高人类生活水平的重要物质基础，电力的应用在不断深化和发展，电气自动化是国民经济和人民生活现代化的重要标志。学术堂整理了十五个电气工程论文题目供大家进行参考：1、短路电流计算曲线的算法研究及与IEC短路电流计算法的对比2、计算曲线法用于大容量机组短路电流计算的评估3、崇明电网配置低压减载装置的必要性和可行性研究4、电压稳定计算中配网模型的研究5、上海电网电压稳定极限运行能力分析6、发电机励磁系统模型对短路电流计算结果的影响7、联络线功率对上海电网电压稳定极限运行的影响8、采用“干预法”估计谐波阻抗9、波过程试验装置的研制10、直流电源中可控硅控制电路的设计11、应用于波过程试验装置的频率可调方波发生器的研制12、水位测量仪的液晶显示器电路的设计13、基于R232、R485的无线数据通信系统的设计14、直流电源中脉冲宽度控制电路的设计15、红外温度测试系统中数据采集电路的设计
用于分布式在线UPS中的并联逆变器的一种无线控制器A Wireless Controller for Parallel Inverters in Distributed Online UPS SystemsJosep M. Guerrero', Luis Garcia de Vicufia", Jose Matas'*, Jaume Miret", and Miguel Castilla". Departament #Enginyeria de Sistemes, Automatica i Informhtica Industrial. Universitat Polithica de CatalunyaC. Comte d'Urgell, 187.08036 -Barcelona. Spain. Email: .. Departament #Enginyeria Electrbnica. Universitat Polit6cnica de CatalunyaAV. Victor BaLguer s/n. 08800I - Vilanova i la Geltrh. SpainAbsiract - In this paper, a novel controller for parallelconnectedonline-UPS inverters without control wireinterconnections is presented. The wireless control technique isbased on the well-known droop method, which consists inintroducing P-oand Q-V schemes into the inverters, in order toshare properly the power drawn to the loads. The droop methodhas been widely used in applications of load sharing betweendifferent parallel-connected inverters. However, this methodhas several drawbacks that limited its application, such as atrade-off between output-voltage regulation and power sharingaccuracy, slow transient response, and frequency and phasedeviation. This last disadvantage makes impracticable themethod in online-UPS systems, since in this case every modulemust be in phase with the utility ac mains. To overcome theselimitations, we propose a novel control scheme, endowing to theparalleled-UPS system a proper transient response, strictlyfrequency and phase synchronization with the ac mains, andexcellent power sharing. Simulation and experimental resultsare reported confirming the validity of the proposed approach.1. INTRODUCTIONThe parallel operation of distributed Uninterruptible PowerSupplies (UPS) is presented as a suitable solution to supplycritical and sensitive loads, when high reliability and poweravailability are required. In the last years, many controlschemes for parallel-connected inverters has been raised,which are derived from parallel-schemes of dc-dc converters[I], such as the master-slave control [2], or the democraticcontrol [3]. In contrast, novel control schemes have beenappeared recently, such as the chain-structure control [4], orthe distributed control [ 5 ] . However, all these schemes needcontrol interconnections between modules and, hence, thereliability of the system is reduced since they can be a sourceof noise and failures. Moreover, these communication wireslimited the physical situation ofthe modules [6].In this sense, several control techniques has been proposedwithout control interconnections, such as the droop method.In this method, the control loop achieves good power sharingmaking tight adjustments over the output voltage frequencyand amplitude of the inverter, with the objective tocompensate the active and reactive power unbalances [7].This concept is derived from the power system theory, inwhich the frequency of a generator drops when the powerdrawn to the utility line increases [8].0-7803-7906-3/03/$17.00 02003 IEEE. 1637However, this control approach has an inherent trade-offbetween voltage regulation and power sharing. In addition,this method exhibits slow dynamic-response, since it requireslow-pass filters to calculate the average value of the activeand reactive power. Hence, the stability and the dynamics ofthe whole system are hardly influenced by the characteristicsof these filters and by the value of the droop coefficients,which are bounded by the maximum allowed deviations ofthe output voltage amplitude and frequency.Besides, when active power increases, the droopcharacteristic causes a frequency deviation from the nominalvalue and, consequently, it results in a variable phasedifference between the mains and the inverter output voltage.This fact can be a problem when the bypass switch mustconnect the utility line directly to the critical bus in stead ofits phase difference. In [9], two possibilities are presented inorder to achieve phase synchronization for parallel lineinteractiveUPS systems. The first one is to locate a particularmodule near the bypass switch, which must to synchronizethe output voltage to the mains while supporting overloadcondition before switch on. The second possibility is to waitfor the instant when phase matching is produced to connectthe bypass.However, the mentioned two folds cannot be applied to aparallel online-UPS system, since maximum transfer timeought to be less than a % of line period, and all the modulesmust be always synchronized with the mains when it ispresent. Hence, the modules should be prepared to transferdirectly the energy from the mains to the critical bus in caseof overload or failure [lo].In our previous works [11][12], we proposed differentcontrol schemes to overcome several limitations of theconventional droop method. However, these controllers bythemselves are inappropriate to apply to a parallel online-UPS system. In this paper, a novel wireless control scheme isproposed to parallel different online UPS modules with highperformance and restricted requirements. The controllerprovides: 1) proper transient response; 2) power sharingaccuracy; 3) stable frequency operation; and 4) good phasematching between the output-voltage and the utility line.Thus, this new approach is especially suitable for paralleled-UPS systems with true redundancy, high reliability andpower availability. Simulation and experimental results arereported, confirming the validity of this control scheme.Fig. 1. Equivalenl cimuif ofan invener connecled 10 a bust"Fig. 2. P-odraop function.11. REVlEW OF THE CONVENTIONAL DROOP METHODFig. 1 shows the equivalent circuit of an inverter connectedto a common bus through coupled impedance. When thisimpedance is inductive, the active and reactive powers drawnto the load can be expressed asEVcosQ - V2 Q=where Xis the output reactance of an inverter; Q is the phaseangle between the output voltage of the inverter and thevoltage of the common bus; E and V are the amplitude of theoutput voltage of the inverter and the bus voltage,respectively.From the above equations it can be derived that the activepower P is predominately dependent on the power angle Q,while the reactive power Q mostly depends on the outputvoltageamplitude. Consequently, most of wireless-control ofparalleled-inverters uses the conventional droop method,which introduces the following droops in the amplitude Eand the frequency U of the inverter output voltageu = w -mP (3)E = E ' - n Q , (4)being W* and E' the output voltage frequency and amplitudeat no load, respectively; m and n are the droop coefficientsfor the frequency and amplitude, respectively.Furthermore, a coupled inductance is needed between theinverter output and the critical bus that fixes the outputimpedance, in order to ensure a proper power flow. However,it is bulky and increase:; the size and the cost of the UPSmodules. In addition, tho output voltage is highly distortedwhen supplying nonlinezr loads since the output impedanceis a pure inductance.It is well known that if droop coefficients are increased,then good power sharing is achieved at the expense ofdegrading the voltage regulation (see Fig. 2).The inherent trade-off of this scheme restricts thementioned coefficients, which can be a serious limitation interms of transient response, power sharing accuracy, andsystem stability.On the other hand, lo carry out the droop functions,expressed by (3) and (4), it is necessary to calculate theaverage value over one line-cycle of the output active andreactive instantaneous power. This can be implemented bymeans of low pass filters with a smaller bandwidth than thatof the closed-loop inverter. Consequently, the powercalculation filters and droop coefficients determine, to a largeextent, the dynamics and the stability of the paralleledinvertersystem [ 131.In conclusion, the droop method has several intrinsicproblems to be applied 1.0 a wireless paralleled-system ofonline UPS, which can he summed-up as follows:Static trade-off between the output-voltage regulation(frequency and amplitude) and the power-sharingaccuracy (active an4d reactive).2) Limited transient response. The system dynamicsdepends on the power-calculation filter characteristics,the droop coefficients, and the output impedances.Lost of ac mains synchronization. The frequency andphase deviations, due to the frequency droop, makeimpracticable this method to a parallel-connectedonline UPS system, in which every UPS should becontinuously synchronized to the public ac supply.1)3)111. PROPOSED CONTROL FOR PARALLEL ONLINE UPSINVERTERSIn this work, we will try to overcome the above limitationsand to synthesize a novel control strategy withoutcommunication wires that could be appropriate to highperformanceparalleled industrial UPS. The objective is toconnect online UPS inverters in parallel without usingcontrol interconnections. This kind of systems, also namedinverter-preferred, should be continuously synchronized tothe utility line. When an overload or an inverter failureoccurs, a static bypass switch may connect the input line tothe load, bypassing the inve:rter [14][15].Fig. 3 shows the general diagram of a distributed onlineUPS system. This system consists of two buses: the utilitybus, which is connected lo the public ac mains; and thesecure bus, connected to the distributed critical loads. Theinterface between these buses is based on a number of onlineUPS modules connected in parallel, which providescontinuously power to the: loads [16]. The UPS modulesinclude a rectifier, a set of batteries, an inverter, and a staticbypass switch.11638Q ac mainsutility busI I Ij distributed loads !Fig. 3. Online distributed UPS system.syposr /I 4(4Fig. 4. Operation modes of an online UPS.(a) Normal operation. (b) Bypass operation. (c) Mains failureThe main operation modes of a distributed online UPS1) Normal operation: The power flows to the load, fromthe utility through the distributed UPS units.2) Mains failure: When the public ac mains fails, theUPS inverters supply the power to the loads, from thebatteries, without disruption.Bypass operation: When an overload situation occurs,the bypass switch must connect the critical busdirectly to the ac mains, in order to guarantee thecontinuous supply of the loads, avoiding the damageof the UPS modules.For this reason, the output-voltage waveform should besynchronized to the mains, when this last is present.system are listed below (see Fig. 5):3)Nevertheless, as we state before, the conventional droopmethod can not satisfy the need for synchronization with theutility, due to the frequency variation of the inverters, whichprovokes a phase deviation.To obtain the required performance, we present a transientP-w droop without frequency-deviation in steady-state,proposed previously by OUT in [ 111w=o -mP (5)where is the active power signal without the dccomponent,which is done by. -I t -1sP= p ,( s + t - ' ) ( s + o , )being zthe time constant of the transient droop action.The transient droop function ensures a stable frequencyregulation under steady-state conditions, and 'at the sametime, achieves active power balance by adjusting thefrequency of the modules during a load transient. Besides, toadjust the phase of the modules we propose an additionalsynchronizing loop, yieldingo=w'-m%k,A$, (7)where A$ is the phase difference between the inverter and themains; and k, is the proportional constant of the frequencyadjust. The steady-state frequency reference w* can beobtained by measuring the utility line frequency.The second term of the previous equality trends to zero insteady state, leading tow = w' - k4($ -@'), (8)being $and $* the phase angles of the output voltage inverterand the utility mains, respectively.Taking into account that w = d $ / d t , we can obtain thenext differential equation, which is stable fork, positived$ *dt dt- + km$ = - + k,$' . (9)Thus, when phase difference increases, frequency willdecrease slightly and, hence, all :he UPS modules will besynchronized with the utility, while sharing the power drawnto the loads.IV. CONTROLLIEMRP LEMENTATIONFig. 5 depicts the block diagram of the proposedcontroller. The average active power P , without the dccomponent, can be obtained by means of multiplying theoutput voltage by the output current, and filtering the product........................................................................................io",.LSj'nchronirorion loop.......................................................................................Fig. 5. Block diagram of the proposed controller.using a band-pass filter. In a similar way, the averagereactive power is obtained, hut in this case the output-voltagemust be delayed 90 degrees, and using a low-pass filter.In order to adjust the output voltage frequency, equation(7) is implemented, which corresponds to the frequencymains drooped by two transient-terms: the transient activepower signal term; and the phase difference term, whichis added in order to synchronize the output voltage with theac mains, in a phase-locked loop (PLL) fashion. The outputvoltageamplitude is regulated by using the conventionaldroop method (4).Finally, the physical coupled inductance can be avoided byusing a virtual inductor [17]. This concept consists inemulated an inductance behavior, by drooping the outputvoltage proportionally to the time derivative of the outputcurrent. However, when supplying nonlinear loads, the highordercurrent-harmonics can increase too much the outputvoltageTHD. This can be easily solved by using a high-passfilter instead of a pure-derivative term of the output current,which is useful to share linear and nonlinear loads [I 1][12].Furthermore, the proper design of this output inductance canreduce, to a large extent, the unbalance line-impedanceimpact over the power sharing accuracy.v. SIMULATION AND EXPERIMENTARELS ULTSThe proposed control scheme, (4) and (7), was simulatedwith the parameters listed in Table 1 and the scheme shownin Fig. 6, for a two paralleled inverters system. Thecoefficients m, n, T, and kv were chosen to ensure stability,proper transient response and good phase matching. Fig. 7shows the waveforms of the frequency, circulating currents,phase difference between the modules and the utility line,and the evolution of the active and reactive powers. Note theexcellent synchronization between the modules and theACmiiinr 4 j. ...L...I.P...S...1... ..........................B...u...n...r.r..r..e..s... ................................... iFig. 6. Parallel operation oftwa online UPS modules,mains, and, at the same time, the good power sharingobtained. This characteristik let us to apply the controller tothe online UPS paralleled systems.Two I-kVA UPS modules were built and tested in order toshow the validity of the proposed approach. Each UPSinverter consisted of a single-phase IGBT full-bridge with aswitching frequency of 20 kHz and an LC output filter, withthe following parameters: 1. = 1 mH, C = 20 WF, Vi" = 400V,v, = 220 V, I50 Hz. The controllers of these inverters werebased on three loops: an inner current-loop, an outer PIcontroller that ensures voltage regulation, and the loadsharingcontroller, based on (4) and (7). The last controllerwas implemented by means of a TMS320LF2407A, fixedpoint40 MHz digital sigrial processor (DSP) from TexasInstruments (see Fig. 8), using the parameters listed in TableI. The DSP-controller also includes a PLL block in order tosynchronize the inverter with the common bus. When thisoccurs, the static bypass switch is tumed on, and the droopbasedcontrol is initiated.1640big 7 Wa\cfc)rms for twu.invencr, ;mnectcd in parallel. rpchrontred io Ihc ac mdnl.(a) Frequencics ufhoth UPS (b) Clrculattng currcni among modulcs. (CJ Phmc d!Nercn;: betucen ihc UPS a#>dth e ai mum(d) Ikiril uf the phze diNmncc (e) md (0 Activc and rcactlw pouerr "I ooih UPSNote that the iimc-acs arc deliheratcly JiNercni due in thc disiinct timuion*uni) ofthe \ inrblrr1641TABLEI.PARAMETEROSF THE PARALLELESDYS TEM.Filter Order I IFilter Cut-off Frequency I 0, I 10 I ragsFig. 8 shows the output-current transient response of theUPS inverters. First, the two UPS are operating in parallelwithout load. Notice that a small reactive current is circlingbetween the modules, due to the measurement mismatches.Then, a nonlinear load, with a crest factor of 3, is connectedsuddenly. This result shows the good dynamics and loadsharingof the paralleled system when sharing a nonlinearload.Fig. 8. Output current for the two paralleled UPS, during the connection of Bcommon nonlinear load with a crest factor of 3. (Axis-x: 20 mddiv. Axis-y:5 Mdiv.).VI. CONCLUSIONSIn this paper, a novel load-sharing controller for parallelconnectedonline UPS systems, was proposed. The controlleris based on the droop method, which avoids the use ofcontrol interconnections. In a sharp contrast with theconventional droop method, the controller presented is ableto keep the output-voltage frequency and phase strictlysynchronized with the utility ac mains, while maintaininggood load sharing for linear and nonlinear loads. This fact letus to extend the droop method to paralleled online UPS.On the other hand, the proposed controller emulates aspecial kind of impedance, avoiding the use of a physicalcoupled inductance. Th.e results reported here show theeffectiveness of the proposed approach.
随着我国的经济和科技的不断发展，电气技术也渐渐地被人们所关注。下面是由我整理的电气技术论文题目，谢谢你的阅读。 电气技术论文题目 1......浅议电气工程的质量控制和安全管理 2......浅议建筑电气工程防雷 3......浅议PLC在机床电气控制系统改造中的应用 4......机电安装工程电气施工关键工序控制与管理 5......浅议电气误操作事故的原因及对策 6......火力发电厂电气控制系统浅探 7......浅述母差保护基本原理 8......建筑电气工程电线管敷设的质量问题及防范 9......浅议高层民用建筑设计中给排水对电气专业提资要求 10.....浅议钳工一体化实习教学 11.....浅议220kV银湖变电站#2主变压器安装施工技术 12.....电气工程施工常见问题及处理 13.....新建黑龙江伊春林都机场防雷改造工程技术方案浅述 14.....浅议提高自备电厂机组利用小时的措施 15.....浅议某垃圾处理厂的电气与自控设计 16.....浅议我国大型水电机组的发展 17.....浅谈电气工程师的作用 18.....浅谈装修工程中电气施工质量控制要点 19.....电气工程及其自动化专业规范研究 20.....浅议变电站设备检修 21.....学习新《安规》的几点初浅体会 22.....电气工程的管理措施研究 23.....浅议汽轮机组的振动故障和处理、保护措施 24.....电气工程与自动化学院介绍(一) 25.....浅议继电保护装置改进后的运行 26.....浅淡10kV配电网建设与改造方案 27.....永磁电机制造关键工艺浅议 电气技术论文 浅谈电气施工技术 摘要：建筑工程的机电安装是施工工程的重要组成部分，并且贯穿于整个建筑工程施工的各个阶段当中。通过介绍电气工程的施工内容，阐述了各个分部公司的施工方法，重点说明了关键工序的主要细节及控制措施。 关键词：电气工程;施工技术;质量措施 在建筑工程当中，机电安装工程是关键的技术环节，其施工主要包括电气工程、空调和暖通工程、建筑消防工程、弱电工程等具体形式的施工。而这些具体的机电施工，都需要从施工的设备和技术材料的统筹、采购、安装、调试、试运行及竣工后的验收活动等几个步骤进行安排。而每个施工的环节，都会牵扯到技术和质量的有效控制。因此，建筑工程机电施工的整体质量，将直接影响到整个建筑工程的质量，对电气工程的施工技术进行总结，用于指导施工很有意义。 1 施工准备工作 在进行建筑工程机电安装施工工程之前，针对此工程施工对象的基本要求和特点，并根据需要，组织与工程有关的相关部门，并按照部门的设置为其选择部门的管理人员，然后根据图纸绘制的设计要求，派技术人员、管理人员进入施工现场进行工作的交接，并根据人员设置和工程的具体情况，进行施工场所的平面布置和平面规划，更有效的管理和监督施工的工作人员严格按照施工计划和施工图纸进行合理施工。 2 电气工程 2.1电气工程技术特征 建筑工程电气工程施工一般包括高压变电系统、低压配电系统、后备供电系统、照明供电系统、消防控制系统设备、应急的出口指示供电系统、停车场等各个单位的强电供电系统和建筑智能控制、防雷接地等弱电系统。 2.2 在电气工程施工之前，需要做好一系列的准备工作，比如技术人员和管理人员分配问题、施工设备和施工材料的合理配置、施工图纸、设计和施工资料等方面。对结构造型及预埋管线完成线面标定，按照预先做好的电气专业管线图预留和预埋电气管线，利用专业的技术和工艺进行开线槽、桥架穿越楼板、剪力墙处开孔洞处理以及防雷设备的接地焊接。在土建中进行底板结构施工、电气工程在连接时，一般会采用镀锌的电线管丝扣进行连接，并在各个环节要严格按照建筑安装工艺技术的标准和要求要求进行安装工作。 2.3 在墙壁的内部暗敷管线，需要从楼板引上或引下，这是需要处理各种墙壁出现的问题。而在对墙壁进行砌体时，首先要保证终端线盒的定位满足图纸的设计要求，并按照相关规定和业主的要求进行相应操作。在完成砌体后，线盒的位置与尺寸将不能改正，所以砌体钱需要充分统筹，而且最好能一次性准确恰当的完成。接着，由于很多工程环节也会有打孔工作，所以需要作好建筑外部明显的标记，避免其他打孔活动会损坏管线。在安装电气的管线后需要进行整齐排列，管理对支架的牢固程度和管卡的均匀程度，注意线管的弯曲半径、电缆管的半径标准，而且要注意保护关口成喇叭形状，注意关口边缘的光滑程度。在电缆穿管之后 ，要进行密封。 3 电源电路 3.1 在建筑工程的施工过程当中，对于天花的布置和设计，首先应该充分地考虑到灯具所具有的的照明的效果。除了在设计上要符合使用者需要并注重其外观的美观大方外，在进行其相应的安装环节之前，首先应该合理布置和安排照明的灯具、风口、消防的喷头，并且灯具要坚持在风管的下面进行安装。对于一些具有特殊要求等方面的特殊灯具，需要进行密封处理，才能保证灯具功能的发挥。在线路问题上，一般采用镀锌钢管、防水线盒进行敷设。所有建筑场所的开关、插座、疏散等局的安装都需要符合设计高度并保持一致美观。 3.2 线路的检测和调试 电气工程在线路测试与调试包括 ：低压配电柜屏、动力设备、照明设备与控制设备的一、二次回路的各项电参数测试 ，有对地绝缘电阻、线路通断、控制器灵敏度调试及继电保护装置检测调试 ，各项检验与调试必须严格按设备安规与使用说明进行。 4 空调电气系统 鉴于暖通空调系统在机电安装施工中的重要性，除了在技术更新上实现节能降耗外，工程建设业主单位还必须加强多方面的综合管理，全面提升建筑电气工程施工的质量。结合自身的施工经验，现提出优化机电安装施工的综合策略。 4.1 优化设计。暖通空调系统是一项复杂性的机电结构，在安装之前必须做好多方面的设计评估，对机电设备的结构形式进行优化改进。设计阶段发现任何异常问题时，都必须对安装施工方案加以改进，这样才能为后期施工创造有利条件。暖通空调系统需对于每个器件的设计给予重视。 4.2 优化功能。施工单位要对建筑物本身质量实施优化处理，不断提高建筑自身的使用性能为机电安装施工带来便利。暖通空调节能效果的实现要借助于建筑内部功能的优化，这是现代暖通空调系统正常运行的保证。建筑功能优化可借助保温技术、节能技术等方面调整，这对于机电安装是很有利的。 4.3 优化产品。机电安装施工技术调整之后，工程建设业主单位必须严格把关机电设备的质量，对暖通空调设备采取严格的质量审核制度。如此一来，不仅能避免因设备质量问题而影响到机电装置的运行，还能防止暖通空调系统出现各种质量问题，保证了机电安装施工的有序开展。 5 弱电系统 弱电系统主要包含综合布线、计算机网络系统、数字有线电视系统、语音程控交换系统、安防系统、背景音乐 / 消防广播系统、多媒体会议系统、前台公共信息发布系统、防雷接地和 UPS 电源系统等建筑智能化系统以及消防自动警报的系统等。 随着科技的发展，业主对软垫系统的功能要求越来越细致和先进，所以，在进行配置的功能主机模块的选择当中中，要坚持选择技术成熟且先进的品牌产品为先导，在进行综合布线施工工作中，要注意线管材质，一般来说，选用 KBG类金属管子，并有效地做好接地防护工作，注意强电线管间的规范间距问题，这在很大程度上能有效地防止回路干扰的影响。 6 结语 综上所述，电气工程非常重要，需加强技术质量管理，重视施工技术的运用与总结，提高质量把控能力，重视施工工序，确保电气工程的整体质量。 参考文献： [1] 叶卫军.建筑工程机电安装施工技术管理浅析[J].科技传播，2011(2). [2] 小军.中小型水电站机电安装工程预埋阶段监理对质量的控制[M].水电站设计，2010(3). [3] 邓怀智，郗艳梅 .设备安装工程与土建工程的施工配合策略浅析[J]河北工程技术高等专科学校学报 [4]庄贤才，蔡蔚，魏晓斌，尧靖秋.浅谈建筑智能化系统工程督导管理[J].智能建筑.2008(4). 作者简介：张利勇(1981.09-)，男，身份证号码410727198109065918，从事施工管理。 看了“电气技术论文题目”的人还看： 1. 电气专业论文范文 2. 电气工程前沿技术论文 3. 电气工程方面的论文 4. 电气自动化技术论文范文 5. 电子技术论文题目
电气工程毕业论文题目
随着经济生活水平的不断提高，人们对电气安装工程质量有了更高的要求。以下是电气工程毕业论文题目，欢迎阅读。
1、建筑电气工程施工中的质量控制和安全管理强化策略探讨
2、建筑电气施工质量问题及应对措施分析
3、探究建筑电气工程的智能化技术应用
4、基于Android的建筑电气无线监控系统研究与实现
5、《民用建筑电气设计规范》相关释疑
6、建筑电气低压配电设计中各种接地系统的探讨
7、建筑电气工程中的强电施工与设计方法分析
8、建筑电气工程施工质量控制要点分析
9、提高建筑电气工程施工管理的措施
10、建筑电气工程的智能化技术应用分析
11、基于REVIT的建筑电气BIM协同设计分析
12、建筑电气自动化系统安装的施工技术探讨
13、关于建筑电气在节能方面的几点思考
14、建筑电气设计中的消防设计之我见
15、建筑电气中供配电线路设计的思考
16、建筑电气工程安装技术要点探析
17、建筑电气照明节能设计略谈
18、建筑电气与智能化专业人才培养模式改革思路
19、切实提高文物建筑电气火灾防控能力[N]
20、论建筑电气工程的施工质量管理
21、建筑电气设计安装问题及解决对策
22、建筑电气施工质量通病与控制措施探析
23、建筑电气强电部分设计的.相关问题和应对策略
24、住宅小区的建筑电气设计探析
25、建筑电气火灾的现状、问题和防控
26、浅析建筑电气技术在智能建筑中的应用
27、智能化技术在建筑电气工程中的应用
28、高层楼宇建筑电气节能技术研究
29、建筑电气技术在工程中的应用及发展趋势
30、建筑电气工程安装技术要点分析及应用
31、DB模式下建筑电气工程投标报价、设计与造价管理
32、建筑电气的施工现场安全与管理问题分析
33、试论建筑电气安装工程中的问题及对策
34、基于Revit软件的建筑电气设计分析
35、建筑电气设计节能方面的应用
36、建筑电气项目的节能技术
37、建筑电气系统提高照明质量的措施研究
38、民用建筑电气照明系统节能技术分析
39、建筑电气节能问题研究
40、建筑电气施工质量控制要点分析
41、浅析建筑电气专业设备及管线标识的标注
42、建筑电气在住宅节能设计中的应用
43、建筑电气技术在智能建筑建设领域的应用分析
44、建筑电气监控系统监控服务与配置平台开发
45、建筑电气监控系统总线节点的功能可配置性开发
46、基于灰色层次分析法的建筑电气节能设计方案优选
47、简论我国建筑电气设计规范
48、建筑电气工程安装技术要点分析及应用研究
49、建筑电气工程的智能化技术应用分析
50、新时期建筑电气节能途径探讨
51、浅谈建筑电气设计中的节能技术措施
52、建筑电气配电线路的配电方式及防火措施探讨
53、建筑电气系统故障诊断方法研究
54、浅谈建筑电气消防审核和验收中的常见问题
55、建筑电气工程施工管理及质量控制
56、建筑电气安装工程中常见问题分析与预防
57、建筑电气中的SPD电压保护方法研究
58、浅谈建筑电气工程施工中常见的质量通病及防治措施
59、建筑电气工程安装技术要点分析及应用
60、建筑电气安装中防雷接地施工技术的应用与质量管理
61、建筑电气设计中的节能措施探讨
62、建筑电气设计原则与可行性措施
63、建筑电气防水设计探讨
64、建筑电气工程的质量管理和控制措施研究
65、探究建筑设计中的电气消防设计
66、建筑电气工程施工质量控制要点探析
67、关于建筑电气中的消防设计探讨
68、试论建筑电气设计中的节能措施
69、建筑电气照明节能设计研究
70、建筑电气中的低压电气安装
71、建筑工程电气设备安装施工技术的要点分析
72、基于建筑信息模型的电气特性计算仿真
73、高职院校建筑电气课程实践性教学改革探索
74、建筑电气照明节能设计的探讨
75、建筑电气施工质量控制综述
76、建筑电气节能技术的合理应用
77、高层建筑电气设计中低压配电系统安全性探讨
78、建筑电气自动化控制系统的应用
79、对现代建筑电气设计的特点及发展的探讨
80、电力电缆在建筑电气工程中的应用研究
81、建筑电气系统的节能设计
82、基于智能负荷控制器的建筑电气优化布线研究
83、建筑电气设备的电气节能设计研究
84、建筑电气节能问题的研究
85、超高层建筑电气设计关键技术解析
86、小波消噪和人工蜂群优化神经网络的建筑电气故障诊断
87、谐波对建筑电气设计的影响及对策分析
88、试论关于智能化建筑与建筑电气
89、对现代建筑电气设计中的问题探讨
90、建筑节能在建筑电气设计中的应用
91、浅谈病房建筑电气设计中应注意的问题
92、浅谈建筑电气节能技术的应用
93、建筑电气设计存在的问题及主要对策
94、建筑电气消防工程设计及施工策略研究
95、高层建筑电气中的低压配电设计分析
96、建筑电气的低压电气安装技术探讨
97、浅析建筑电气工程施工中的质量控制与安全管理
98、试论建筑电气设计中存在的问题与解决对策
99、BIM技术在建筑电气设计中的应用研究
100、建筑电气工程的施工质量管理的策略构建
1、 高压软开关充电电源硬件设计2、 自动售货机控制系统的设计3、 PLC控制电磁阀耐久试验系统设计4、 永磁同步电动机矢量控制系统的仿真研究5、 PLC在热交换控制系统设计中的应用6、 颗粒包装机的PLC控制设计7、 输油泵站机泵控制系统设计8、 基于单片机的万年历硬件设计 9、 550KV GIS中隔离开关操作产生的过电压计算10、 时滞网络化控制系统鲁棒控制器设计11、 多路压力变送器采集系统设计12、 直流电机双闭环系统硬件设计 13、 漏磁无损检测磁路优化设计14、 光伏逆变电源设计15、 胶布烘干温度控制系统的设计16、 基于MATLAB的数字滤波器设计与仿真17、 电镀生产线中PLC的应用18、 万年历的程序设计19、 变压器设计20、 步进电机运动控制系统的硬件设计21、 比例电磁阀驱动性能比较22、 220kv变电站设计 23、 600A测量级电流互感器设计24、 自动售货机控制中PLC的应用25、 足球机器人比赛决策子系统与运动轨迹的研究26、 厂区35kV变电所设计27、 基于给定指标的电机设计28、 电梯控制中PLC的应用29、 常用变压器的结构及性能设计30、 六自由度机械臂控制系统软件开发31 输油泵站热媒炉PLC控制系统设计32 步进电机驱动控制系统软件设计33 足球机器人的视觉系统与色标分析的研究34 自来水厂PLC工控系统控制站设计35 永磁直流电动机磁场分析36 永磁同步电动机磁场分析37 应用EWB的电子表电路设计与仿真38 电路与电子技术基础》之模拟电子篇CAI课件的设计39 逻辑无环流直流可逆调速系统的仿真研究40 机器人足球比赛图像采集与目标识别的研究41 自来水厂plc工控系统操作站设计42 PLC结合变频器在风机节能上的应用43 交流电动机调速系统接口电路的设计44 直流电动机可逆调速系统设计45 西门子S7-300PLC在二氧化碳变压吸附中的应用46 DMC控制器设计47 电力电子电路的仿真48 图像处理技术在足球机器人系统中的应用49 管道缺陷长度对漏磁场分布影响的研究 50 生化过程优化控制方案设计51 交流电动机磁场定向控制系统设计52 开关电磁阀流量控制系统的硬件设计53 比例电磁阀的驱动电源设计54 交流电动机SVPWM控制系统设计55 PLC在恒压供水控制中的应用56 西门子S7-200系列PLC在搅拌器控制中的应用57 基于侧抑制增强图像处理方法的研究58 西门子s7-300系列plc在工业加热炉控制中的应用59 西门子s7-200系列plc在电梯控制中的应用60 PLC在恒压供水控制中的应用61 磁悬浮系统的常规控制方法研究62 建筑公司施工进度管理系统设计63 网络销售数据库系统设计64 生产过程设备信息管理系统的设计与实现
这类的选题有很多，在这里大家可以参考一下往期的论文选题，如：高功率引述整流器的建模与仿真、直流电机闭环控制调速系统的SIMULINK软件仿真、电力系统故障录波器的实验平台开发、抽油机抽空监测及控制器的软件设计、电容器分时投切无功补偿技术在抽油机上的应用研究、油水分离罐的自动运行系统的开发、新型开关电源拓扑的PSPICE的仿真研究、配电网单相接地故障选线的仿真，等等，这类的选题有很多，大家想要了解相关信息不妨来期刊目录网看看。
1. PLC控制花样喷泉.doc 2. S7-200PLC在数控车床控制系统中的应用 3. PLC控制五层电梯设计 4. 超高压水射流机器人切割系统电气控制设计 5. 基于PLC的恒压供水系统设计 6. 西门子PLC交通灯毕业设计 7. 双恒压供水西门子PLC毕业设计 8. 世纪星组态 PLC控制自动配料系统毕业论文 9. 三菱梯形图PLC控制四层电梯 10.三菱PLC五层电梯控制 11.全自动洗衣机西门子PLC控制 12.欧姆龙PLC控制交通灯 13.基于PLC电机故障诊断系统设计 14.双恒压无塔供水系统plc设计毕业论文 15.工业用洗衣机的PLC控制 16.PLC在配料生产线上的应用 毕业论文 17.变频调速恒压供水系统 18.PLC电梯控制毕业论文 19.基于PLC电梯控制设计 20.基于PLC中断技术的集选电梯控制系统实现
楼主是什么歇学习阶段呢，你擅长什么呢？
1 电气自动化和电脑的整合运用。2 电气自动化和移动通讯的整合运用3 自动化组装机取代人工生产线的规划运用4 电气自动化的数据收集和统计分析5 电气自动化用于质量管理的规划和运用6 电气自动化运用在精益生产线的规划和分析这些都是目前比较有深度的题目
1.PLC控制花样喷泉.doc 2.S7-200PLC在数控车床控制系统中的应用3.PLC控制五层电梯设计 4.超高压水射流机器人切割系统电气控制设计5.基于PLC的恒压供水系统设计 6.西门子PLC交通灯毕业设计7.双恒压供水西门子PLC毕业设计 8.世纪星组态PLC控制自动配料系统毕业论文9.三菱梯形图PLC控制四层电梯 10.三菱PLC五层电梯控制11.全自动洗衣机西门子PLC控制 12.欧姆龙PLC控制交通灯13.基于PLC电机故障诊断系统设计 14.双恒压无塔供水系统plc设计毕业论文15.工业用洗衣机的PLC控制 16.PLC在配料生产线上的应用毕业论文17.变频调速恒压供水系统 18.PLC电梯控制毕业论文19.基于PLC电梯控制设计 20.基于PLC中断技术的集选电梯控制系统实现
随着信息网络技术发展水平的不断提高，发电厂电气技术也渐渐地被人们所关注。我为大家整理的发电厂电气技术论文，希望你们喜欢。 发电厂电气技术论文篇一 发电厂电气自动化技术初探 摘要：本文分析了发电厂用电系统的特点，通过介绍电气综合自动化系统的功能，探讨了目前电气自动化控制系统的设计思想，展望了将来电气自动化控制系统的发展趋势。 关键词：发电厂;电气自动化;技术;分析 中图分类号：TU984 文献标识码：A 文章编号： 从布置方式和数量上来看，厂用电设备分散安装于各配电室和电动机控制中心，元件数量众多，运行管理信息量大，检修维护工作复杂。与热工系统相比较， 电气设备操作频率低，有的系统或设备运行正常时，几个月或更长时间才操作一次;电气设备保护自动装置要求可靠性高动作速度快，比如保护动作速度要求在40ms 以内完成。在电气设备本身构造上，其具有联锁逻辑较简单、操作机构复杂的特点。在构建ECS时，其系统结构与DCS 的联网方式是确保系统高可靠性的关键。既要实现正常起停和运行操作外，又要实现实时显示异常运行和事故状态下的各种数据和状态并提供相应的操作指导和应急处理措施，保证电气系统在最安全合理的工况下工作。 1 集中模式 1.1 原理 集中模式也就是传统的硬接线方式，将强电信号转变为弱电信号，采用空接点方式和4—20mA标准直流信号，通过电缆硬接线将电气模拟量和开关量信号一对一接至DCS的I/O模件柜，进入DCS进行组态， 实现对电气设备的监控。这种模式又分为直接I/0接人方式和远程I/0接人方式两种，前者是将电缆接至电子间集中组屏，后者是在数据较集中且离主控室较远的电气设备现场设立远程I/0采集柜，然后通过通信方式与 DCS控制主机相连，两者具有相同的实现技术，本质上没有区别。 1.2 优点 电气量的采集集中组屏，便于管理，设备运行环境好;硬接线方式成熟，响应速度快。 1.3 缺点 1.3.1 电缆数量大，电缆安装工程量大，长距离电缆引进的干扰也可能影响DCS的可靠性。 1.3.2 DCS系统按“点”收费，不仅投资大，而且只有重要的电气量才能进入DCS，系统监测的电气信息不完整。 1.3.3 所有信息量均要集中汇总至 DCS系统，风险集中，影响系统可靠性。 1.3.4 由于 DCS调试一般是最后进行，采用集中模式通常难以满足倒送厂用电的要求。 1.3.5 没有独立的电气监控主站系统，无法完成较复杂的电气运行管理工作(如防误、事故追忆、继电保护运行与故障信息自动化管理、录波分析等高级应用功能)，不能实现电气的“综合自动化”。 2 分层分布式模式 2.1 原理 分层分布式模式从逻辑上将ECS划分为三层，即站级监控层、通信层和间隔层(间隔单元)。间隔层由终端保护测控单元组成，利用面向电气一次回路或电气间隔的方法进行设计，将测控单元和保护单元就地分布安装在各个开关柜或其他一次设备附近。网络层由通信管理机、光纤或电缆网络构成，利用现场总线技术，实现数据汇总、规约转换、转送数据和传控制命令的功能。站级监控层通过通信网络，对间隔层进行管理和交换信息。 2.2 优点 2.2.1 间隔层测控终端就地安装，减少占用面积，各装置功能独立，组态灵活，可靠性高。 2.2.2 模拟量采用交流采样，节省二次电缆，降低了成本，抗干扰能力增强，系统采集的数据精度大大提高。 2.2.3 系统采集的数据量提高，监控信息完整，能实现在远方对保护定值的修改及信号复归，运行维护方便。 2.2.4 分布式结构方便系统扩展和维护，局部故障不影响其他模块(部件)正常运行。 2.2.5 设置独立的电气监控主站，便于分步调试和投运，满足倒送电的要求。同时有利于厂用电系统的运行、维护和检修。 2.3 关键技术 2.3.1 间隔层终端测控保护单元。分层分布式系统的最大特点就是以间隔层一次设备为单位，现场配置测控保护单元。该单元是保障厂用电系统安全、稳定运行最重要、最有效的技术手段，对其可靠性、灵敏性、速动性和选择性都有很高的要求，因此不宜由DCS来实现保护功能，而应该采用专用保护装置来实现。厂用电系统保护主要有线路、厂用变、电动机综合保护测控装置等，实现微机化保护、实时数据采集、 远方及就地控制以及记录故障数据等功能。 2.3.2 通信网络。 ECS系统安装工作于高电压、大电场的环境，工作环境恶劣、电磁干扰大，因而通信网络是ECS系统的关键组成部分，通信网络的性能直接影响着自动化监控系统的整体性能。目前较为流行的采用电缆现场总线网络方式，光纤通信亦开始被用户逐步接受。 通信管理层是间隔层和站控层之间的桥梁，方案中一般采用双冗余的设计思想，按照通信管理机双机热备用或双通道备用原则配置，当数据通信网络中出现问题时，系统能自动切换至冗余装置或通道，以提高系统可靠性。 2.3.3 监控主站。监控主站安置在站级监控层，实现厂用电电气系统监控和管理，主站配置的设备和规模需要根据发电机机组的容量和运行管理要求进行设计，即可以配置成单机、双机或多机系统，标准的设备主要有数据库服务器、应用和Web服务器、操作员站、工程师站 以及其他网络设备、GPS和打印机。 尽管配置的设备规模不同，但配置的软件以及完成的功能基本一样。软件主要有前置机软件、实时数据库软件、人机界面软件和图形建模软件等。功能主要有系统监控功能、数据管理功能、系统管理功能以及应用分析功能等。 另外，主站系统可通过多种方式与DCS系统、MIS系统和SIS系统传输数据。 2.3.4ECS与DCS的协调控制。由于电气系统与热工系统在运行过程和控制要求上有着很多不同之处，所以在设计规划阶段和调度运行过程时必须要考虑 ECS与DCS系统之间的功能分工和协调控制，主要体现在以下几点： 由DCS实现电动机连锁逻辑控制操作，厂用电自动切换逻辑由专用电气装置实现。 由ECS实现继电保护、故障录波和事故追忆等功能的管理。 控制操作主要在DCS操作员工作站进行，DCS系统授权后也可在ECS操作员工作站进行，但要保证控制权的唯一性。 3 技术的发展趋势 3.1 嵌入式工业以太网技术的应用 由于现场总线通信协议技术标准的多样性，难以统一，使其不能满足以上性能要求，而以太网由于其传输速度快、容量大、网络拓扑结构灵活以及低成本等特点，在商业领域和工业领域内得到了大规模的应用。该技术成为建立电气综合自动化中无缝通信的最好选择。 工业以太网技术直接应用于工业现场设备间的通信已成大势所趋。随着以太网通信速率的提高，全双工通信、交换技术的发展，为以太网的通信确定性问题的解决提供了技术基础，从而为以太网直接应用于工业现场设备间通信提供了技术可能。 利用嵌入式软、硬件，在单片机系统上实现工业以太网技术又称为嵌入式以太网。国外大的电力设备供应商纷纷推出了基于嵌入式以太网的微机保护测控设备 ，国内电力装备制造商开发的最新综合自动化系统中，也把嵌人式以太网成功应用于二次保护控制设备，因而嵌入式以太网是电气综合自动化系统间隔层网络通信的必然发展方向。 3.2综合智能化技术的应用 ECS系统控制发展经由计算机控制取代了传统操作盘控制，目前又由计算机控制向综合智能控制和管理发展，主要表现在间隔层和站控层两方面。 间隔层的保护和测控单元由传统的相对独立设计，向着集保护、测量、控制、远动于一体的综合化及网络化智能保护测控单元发展，直接面向一次设备或设备组合，就地安装，除实现继电保护、实时电量监控、状态信息记录及历史记录等基本功能外，还能与站控层联网实现事故分析、状态监视、微机防误操作和安全保障等功能。 站控层监控系统由满足基本运行SCADA功能，向全面提高运行和管理自动化水平发展。监控主站采用先进的数据挖掘技术对电气实时数据仓库和历史数据仓库的数据进行分析，提供一系列的高级应用功能。这些功能分为对外和对内两大部分。对外的功能是指给DCS和SIS等其他系统提供数据，实现机组优化控制和优化管理等综合智能控制;对内的功能是指集间隔层装置的监控管理、自动抄表、设备管理、定值管理、故障信息管理、设备在线诊断和小电流接地选线等功能于一体。 4 结束语 本文提出了厂用电电气自动化技术的发展趋势，随着IEC国际标准在工业化领域内的认同和应用普及，基于同一国际标准的全开放式的数字化厂用电电气综合自动化将是下一步研究的重点。 参考文献： [1] 庞军.电气自动化监控技术在电厂中的应用发展[J].能源电力,2011，(7). [2] 张俊.电力系统中电气自动化技术的探索[J].中国新技术新产品,2010，(9). 发电厂电气技术论文篇二 发电厂电气自动化技术应用方法初步研究 摘 要：随着我国社会经济的不断发展，我国东西部经济发展不平衡也日渐显著，特别是在发电厂自动化技术应用及研究上存在着很大的差距，在一些发展比较缓慢的地区，各种原因造成的安全问题还时有发生。本文就发电厂自动化技术的应用进行了相关问题的探讨和研究，通过对电网系统自动化控制模式的完善，以及对现有成功使用案例的研究，制定出配置更加灵活和更容易维护的自动化控制技术。 关键词：热工自动化;电气自动化;电气监控系统 中图分类号：TM76 文献标识码：A 文章编号：1674-7712 (2013) 20-0000-01 发电厂的自动化控制系统的配置方式和数量相对比较复杂，同时在设计的过程中往往会使用较多的电器元件，所以运行管理中需要控制的信息量十分庞大。多种因素共同造成了对于发电自动控制系统检修工作的复杂性。所以在电器设备的自动化控制中需要提高电器设备的可靠性和运行效率。 一、发电厂自动化技术基本功能 发电厂的自动化控制过程中的一个重要工作环节就是对相关信息的搜集，这个工作环节的最主要作用就是将发电厂工作现场的各种模拟数据信息经过计算机系统进行检验，在检验的过程中如果发现被处理数据存在偏差还可以同时进行合理性的矫正，这有利于对重要数据进行整理。一般情况下，对模拟信号进行采集的过程中，同时也要对电流、功率等因素进行测定。在检测过程中检测的数据将通过画面进行直接显示，屏幕上主要显示发电厂工作的所有模拟量、相关的计算量，开关、断路器数据等多种相关数据，处于挂牌检修状态的部分电器元件也将显示在屏幕上。 自动化系统中的检测警报功能能够使得工作人员将发电厂的全部设备的运行信息的实时状态了如指掌，在进行数据监控的同时还能够将系统的信息结合画面的功能显示出来。如在发电厂中的模拟量如果发生超越极限的情况，监视功能控制系统就会自动地将发生越界的对象的名称、编号、时间以及相关参数值等多种重要数据显示出来，同时进行打印和上传，还能够对发生次数进行计算。警报分为事故警报和预告警报两种方式，这两种方式通过不同的颜色进行显示，通过分析不同的颜色进行区分。 在进行实际操作的工作过程中主要分为两级别控制、现场自动控制、上机控制和DCS控制着四种控制方法，其中后三种控制方式比第一种控制方式更为灵活，具有更强的可操作性，命令操作的顺序成为操作优先级，保证合理的操作优先级可以确保控制系统的一致性和安全性，能够极大地提高安全生产的效率。一旦发电厂的某些重要设备发生安全事故，控制系统将会对信息进行及时上传，通过计算机的计算进行快速反应，同时制定出最合理的解决方案。在事故处理结束后会自动对数据进行分析和储存，得出系统性的解决办法，预防类似事故的再次发生。 二、发电厂的新型电气化自动控制技术 随着发电厂自动化控制系统科技的不断发展，一种建立在先进信息化平台上的发电厂自动化控制系统越来越多地应用于生产领域。其中ECS系统在发电厂电气控制系统中应用比较广泛的一种系统，这种系统具有计算机处理、信号的采集与处理、现场总线技术、以太网、继电保护等技术综合研发。应用计算机、现场总线、以太网、信号处理、继电保护等技术实现对发电厂的发电机、变压设备、电动机、反馈线等电器设备以及电气化装置的测量、处理、控制、保护、监测、故障分析、保护等多种功能。这种系统采用了分层式的系统架构，自下向上分别为控制层、管理层和间隔层，其中控制层包括了硬件服务、工作站硬件等方面的工作硬件。主要通过电抄表、录波分析等应用软件进行各种工作系统的通信连接。 ECS工作系统采用了一体化设计的方式将管理层和站控层进行了一体化设计，保证了组态调试可以一次性完成，极大地提高了调试的工作效率，同时从整体的角度完善了系统的通信工作功能，保证了通信层和间隔层之间的通信速度，并且使用DCS、MIS等数据端作为通讯接口，使得ECS和DCS之间的相互通信不受限制，还可以节省大量通信线缆和变送器设备，降低工作成本。同时系统采用了先进的自动化设备，完全实现了不受通讯限制的独立运行，保证了系统工作的安全性和可靠性。 GCS监控系统的间隔层使用的测控系统具有比较完善的屏蔽和隔离组件，因此该系统的抗干扰能力较强，能够适用于各种复杂的工作环境。而且系统中还使用了新型的冗余技术，实现了双线网络控制、站控设备冗余以及双层以太控制等多种模式控制，从工作效率上确保了工作系统的稳定性。工作系统中的安全部件当中还设置有防火墙等多种杀毒措施，并且根据网络分段和数据加密等多种方式提高了网络信息传输的安全性。除此之外，在ECS工作系统中还增加了系统的自我诊断和自我恢复的功能，这是传统电器设备所不具备的。这就使得监控系统的间隔层、站控层和管理层具备了自我修复的功能。在通信层和管理层之间还添加了一种类似于熔断的网络数据中断方式，这就在很大程度上提高了监控系统自我修复的效率。同时在通信管理层中使用了双通道进行数据的备份、恢复和及时上传，提高了信息传输和信息数据处理的效率。系统采用了具有更高性能的微处理器，硬件的配置上也选择了具有多个CPU的智能化结构主机，确保在巨大数据计算工作量时不至使得硬件损坏，同时在操作系统上使用了领先水平的嵌入式多个任务可以同时进行操作的操作系统，这就极大地提高了数据的处理速度和处理效率，保证了发电厂的工作效率和安全工作系数，保证了发电厂的固定财产和工作人员的生命财产安全。 三、结束语 综上所述，发电厂的自动化控制系统是由一组独立分布的计算机控制系统进行控制的，和电厂的运行电气相比，这个方案比较经济且更加具有可行性。随着信息网络技术发展水平的不断提高，网络化的信息技术工作效率也越来越高，在不久的将来将全面实现发电厂电气控制系统工作的完全自动化，同时最终实现和DCS系统的合并，实现较大规模的信息资源共享，这将使得电力系统自动化控制进入到一个新的发展阶段。 参考文献： [1]冯兴林.高速公路交通监控系统技术应用的探讨[J].中国新技术新产品，2012. [2]邵景峰，杨丽萍，李永刚.整经机网络化监控系统软件设计[J].太原理工大学学报，2013. [3]张煜明，厉红娅.新加坡D2563K6型高架门座起重机的电气系统[J].起重运输机械，2011. [4]吴胜强，李铁，尹德胜.DJK型无线调车机车信号及监控系统的推广应用[J].铁道通信信号，2012. 看了“发电厂电气技术论文”的人还看： 1. 电厂电气方面的技术论文 2. 电厂电气方面的技术论文(2) 3. 电气自动化技术论文范文 4. 电气专业论文范文 5. 电气工程及其自动化专业论文
1. PLC控制花样喷泉.doc 2. S7-200PLC在数控车床控制系统中的应用3. PLC控制五层电梯设计 4. 超高压水射流机器人切割系统电气控制设计5. 基于PLC的恒压供水系统设计 6. 西门子PLC交通灯毕业设计7. 双恒压供水西门子PLC毕业设计 8. 世纪星组态 PLC控制自动配料系统毕业论文9. 三菱梯形图PLC控制四层电梯 10.三菱PLC五层电梯控制11.全自动洗衣机西门子PLC控制 12.欧姆龙PLC控制交通灯13.基于PLC电机故障诊断系统设计 14.双恒压无塔供水系统plc设计毕业论文15.工业用洗衣机的PLC控制 16.PLC在配料生产线上的应用 毕业论文17.变频调速恒压供水系统 18.PLC电梯控制毕业论文19.基于PLC电梯控制设计 20.基于PLC中断技术的集选电梯控制系统实现21.自动送料装车系统PLC控制设计 22.简易电梯控制模型的设计与实现.doc23.PLC在数控机床中的应用 24.机械手PLC控制设计25.PLC控制锅炉输煤系统 26.PLC控制自动门的课程设计 27.基于PLC的三层电梯控制系统设计 28.交流变频调速PLC控制电梯系统设计毕业论文29.PLC控制的自动售货机毕业设计论文 30.PLC在变电站变压器自动化中的应用31.PLC在电网备用自动投入中的应用305022336