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水流自动控电技术的研究——电热纯水器的改进
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作者 王金葆 《科技创新与生产力》 2010年第6期84-85,共2页
介绍了电热纯水器工作原理,通过增设断电弹簧、存水吊桶和电闸支架等部件对电热纯水器进行改进,避免了因停水不断电而招致的设备损坏事故,延长了设备的使用寿命,节约了经费开支。
关键词 化学实验室 仪器设备 水流 自动控电 纯水器
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Current Share Control IC Design for Paralleled DC/DC Converters
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作者 陈海 赵梦恋 +1 位作者 吴晓波 严晓浪 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第7期1017-1022,共6页
To keep even current distribution among DC/DC converters in a paralleled power system,an automatic master-slave control (AMSC) current sharing scheme is presented,which was implemented by a current share control IC.... To keep even current distribution among DC/DC converters in a paralleled power system,an automatic master-slave control (AMSC) current sharing scheme is presented,which was implemented by a current share control IC. A current feedback loop for output voltage adjustment is proposed for low signal distortion. Moreover,a special startup control logic is designed to improve startup timing and to speed up the initial current sharing. It was completed in 1.5μm bipolar-CMOS-DMOS (BCD) technology with an area of 3.6mm^2 . Using it,a paralleled power system of two DC/DC converters capable of outputting 12V/3A was built. Experimental results show that the current sharing error at full load is kept within 1%. 展开更多
关键词 DC DC converters Electric potential Signal distortion
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Friction characteristics of a new type of continuous rotary electro-hydraulic servomotor applied to simulator 被引量:5
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作者 曹健 许宏光 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第1期86-89,共4页
The principle of a new type of no-pulsation continuous rotary electro-hydraulic servomotor applied to simulators is introduced. LuGre friction model was analyzed. The identification method of LuGre parameters was prop... The principle of a new type of no-pulsation continuous rotary electro-hydraulic servomotor applied to simulators is introduced. LuGre friction model was analyzed. The identification method of LuGre parameters was proposed, and the measures to compensate the effect of friction forces were given. A friction torque model for the new rotary motor was proposed. The low-speed response and step response of the motor were studied experimentally. Experimental results proved that using friction compensation could eliminate stick-slip motion at the low speed, which makes the servomotor applicable to simulators. 展开更多
关键词 electro-hydraulic servomotor frictional model frictional compensation experimental investigating
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Improved Voltage Control Strategy for Photovoltaic Grid-Connected System Based on DoubleLayer Coordination Control 被引量:3
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作者 戚艳 贾宏杰 《Transactions of Tianjin University》 EI CAS 2012年第4期271-278,共8页
An improved automatic voltage coordination control strategy (AVCCS) based on ;automatic voltage control (AVC) and battery energy storage control (BESC) is proposed for photovoltaic grid-connected system (PVGS)... An improved automatic voltage coordination control strategy (AVCCS) based on ;automatic voltage control (AVC) and battery energy storage control (BESC) is proposed for photovoltaic grid-connected system (PVGS) to mitigate the voltage fluctuations caused by environmental disturbances. Only AVC is used when small environ- mental disturbances happen, while BESC is incorporated with AVC to restrain the voltage fluctuations when large disturbances happen. An adjustable parameter determining the allowed amplitudes of voltage fluctuations is introduced to realize the above switching process. A benchmark low voltage distribution system including ]?VGS is established by using the commercial software Dig SILENT. Simulation results show that the voltage under AVCCS satisfies the IEEE Standard 1547, and the installed battery capacity is also reduced. Meanwhile, the battery's service life is ex- tended by avoiding frequent charges/discharges in the control process. 展开更多
关键词 photovoltaic power system voltage control pulse width modulation (PWM) inverter state ofcharge (SOC) automatic voltage coordination control strategy (AVCCS)
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Hybrid intelligent PID control design for PEMFC anode system 被引量:1
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作者 Rui-min WANG Ying-ying ZHANG Guang-yi CAO 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第4期552-557,共6页
Control design is important for proton exchange membrane fuel cell (PEMFC) generator. This work researched the anode system of a 60-kW PEMFC generator. Both anode pressure and humidity must be maintained at ideal leve... Control design is important for proton exchange membrane fuel cell (PEMFC) generator. This work researched the anode system of a 60-kW PEMFC generator. Both anode pressure and humidity must be maintained at ideal levels during steady operation. In view of characteristics and requirements of the system, a hybrid intelligent PID controller is designed specifically based on dynamic simulation. A single neuron PI controller is used for anode humidity by adjusting the water injection to the hydrogen cell. Another incremental PID controller, based on the diagonal recurrent neural network (DRNN) dynamic identification, is used to control anode pressure to be more stable and exact by adjusting the hydrogen flow rate. This control strategy can avoid the coupling problem of the PEMFC and achieve a more adaptive ability. Simulation results showed that the control strategy can maintain both anode humidity and pressure at ideal levels regardless of variable load, nonlinear dynamic and coupling characteristics of the system. This work will give some guides for further control design and applications of the total PEMFC generator. 展开更多
关键词 Proton exchange membrane fuel cell (PEMFC) Anode system Single neuron Diagonal recurrent neural network (DRNN) PID controller
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Saturation influence of control voltage on maglev stationary self-excited vibration 被引量:3
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作者 李金辉 李杰 余佩倡 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第8期1954-1960,共7页
This work addresses the saturation influence of control voltage on the occurring of self-excited vibration of maglev vehicle-bridge interaction system, which greatly degrades the stability of the levitation control, d... This work addresses the saturation influence of control voltage on the occurring of self-excited vibration of maglev vehicle-bridge interaction system, which greatly degrades the stability of the levitation control, decreases the ride comfort, and restricts the cost of the whole system. Firstly, the interaction model of vehicle-bridge system is developed. Based on the interaction model, the relationship between the control voltage and vibration frequency is solved. Then, the variation of the effective direct component and fundamental harmonic are discussed. Furthermore, from the perspective of energy transmission between the levitation system and bridge, the principle underlying the self-excited vibration is explored, and the influence on the stability is discussed. Finally, in terms of the variation of the characteristic roots, the influence is analyzed further and some conclusions are obtained. This study provides a theoretical guidance for mastering the self-excited vibration problems. 展开更多
关键词 MAGLEV LEVITATION SATURATION self-excited vibration
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Iterative learning control of SOFC based on ARX identification model 被引量:1
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作者 HUO Hai-bo ZHU Xin-jian TU Heng-yong 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第12期1921-1927,共7页
This paper presents an application of iterative learning control (ILC) technique to the voltage control of solid oxide fuel cell (SOFC) stack. To meet the demands of the control system design, an autoregressive model ... This paper presents an application of iterative learning control (ILC) technique to the voltage control of solid oxide fuel cell (SOFC) stack. To meet the demands of the control system design, an autoregressive model with exogenous input (ARX) is established. Firstly, by regulating the variation of the hydrogen flow rate proportional to that of the current, the fuel utilization of the SOFC is kept within its admissible range. Then, based on the ARX model, three kinds of ILC controllers, i.e. P-, PI- and PD-type are designed to keep the voltage at a desired level. Simulation results demonstrate the potential of the ARX model applied to the control of the SOFC, and prove the excellence of the ILC controllers for the voltage control of the SOFC. 展开更多
关键词 Autoregressive model with exogenous input (ARX) lterative learning control (ILC) Solid oxide fuel cell (SOFC) Identification
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A 1.1GHz LC VCO with Automatic Amplitude Control for Tuner Applications
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作者 颜峻 毛威 +5 位作者 马德胜 顾明 许奇明 胡雪青 石寅 代伐 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第7期1189-1195,共7页
This paper presents an LC VCO with auto-amplitude control (AAC), in which pMOS FETs are used,and the varactors are directly connected to ground to widen the linear range of Kvco. The AAC circuitry adds little noise ... This paper presents an LC VCO with auto-amplitude control (AAC), in which pMOS FETs are used,and the varactors are directly connected to ground to widen the linear range of Kvco. The AAC circuitry adds little noise to the VCO but provides it with robust performance over a wide temperature and carrier frequency range.The VCO is fabricated in a chartered 50GHz 0.35μm SiGe BiCMOS process. The measurements show that it has - 127. 27dBc/Hz phase noise at 1MHz offset and a linear gain of 32.4MHz/V between 990MHz and 1.14GHz.The whole circuit draws 6. 6mA current from 5V supply. 展开更多
关键词 TUNER receiver IC LC VCO auto amplitude control
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SC response characteristics of two kinds of coagulant
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作者 杨万东 宋爽 史惠祥 《Journal of Zhejiang University Science》 CSCD 2002年第3期268-271,共4页
Automatic coagulant dosage control with streaming current (SC) technique is introduced in this paper. Aluminum and ferric coagulants are widely used in surface water treatment. The SC response characteristics of P Al... Automatic coagulant dosage control with streaming current (SC) technique is introduced in this paper. Aluminum and ferric coagulants are widely used in surface water treatment. The SC response characteristics of P AlCl 3 aluminum coagulant and P FeCl 3 ferric coagulant were investigated in this work. Bench scale water treatment results were obtained from jar tests including rapid mixing, flocculation and undisturbed sedimentation. Results showed that aluminum coagulant is more sensitive than ferric coagulant to SC response. 展开更多
关键词 Streaming current(SC) SC response COAGULANT Water treatment Automatic control
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Research on Wind Farm Participation in Power Grid AGC Control
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作者 Han XuShan Chen Fei 《Electricity》 2011年第3期27-29,共3页
Since wind power has the features of being intermittent and unpredictable, and usually needs transmission over long distances, grid integration of large-scale wind power will exert signif icant influence on power grid... Since wind power has the features of being intermittent and unpredictable, and usually needs transmission over long distances, grid integration of large-scale wind power will exert signif icant influence on power grid planning and construction, and will make a heavy impact on the safe and reliable operation of power systems. To deal with the diff iculties of large scale wind power dispatch, this paper presents a new automatic generation control (AGC) scheme that involves the participation of wind farms. The scheme is based on ultra-short-term wind power forecast. The author establishes a generation output distribution optimization mode for the power system with wind farms and verif ies the feasibility of the scheme by an example. 展开更多
关键词 wind farm automatic generation control (AGC) power prediction dispatch control
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CMOS Automatic Gain Control Circuit with DC Offset Cancellation for FM/cw Ladar
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作者 赵毅强 徐敏 +2 位作者 庞瑞龙 于海霞 赵宏亮 《Transactions of Tianjin University》 EI CAS 2014年第4期310-314,共5页
This paper presented an automatic gain control (AGC) circuit suitable for FM/cw ladar. The proposed architecture was based on two-stage variable gain amplifier (VGA) chain with a novel DC offset canceller circuit,... This paper presented an automatic gain control (AGC) circuit suitable for FM/cw ladar. The proposed architecture was based on two-stage variable gain amplifier (VGA) chain with a novel DC offset canceller circuit, which contained an improved Gilbert cell and a Gm-C feedback loop. To keep the VGA with a linearity in dB characteristic, an improved exponential gain control circuit was introduced. The AGC was implemented in 0.18 gm standard CMOS process. Simulation and measurement results verified that its gain ranged from -20 dB to 30 dB, and band- width ranged from 100 kHz to 10 MHz. Its power consumption was 19.8 mW under a voltage supply of 3.3 V. 展开更多
关键词 automatic gain control (AGC) variable gain amplifier (VGA) DC offset canceller (DCOC) exponential gain control
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CYLINDER-SPHERE 3-DOF ULTRASONIC MOTOR AND ITS CONTROL
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作者 HUANGWei-qing ZHANFeng-jiang ZHAOChun-sheng 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第4期272-276,共5页
A three degree-of-freedom (DOF) ultrasonic motor (USM) with a cylinder-shaped stator and a spherical rotor is introduced, which uses one first order longitudinal and two second order bending nature vibration modes of ... A three degree-of-freedom (DOF) ultrasonic motor (USM) with a cylinder-shaped stator and a spherical rotor is introduced, which uses one first order longitudinal and two second order bending nature vibration modes of the cylinder. Control strategies for the two DOF trajectory following are studied and applied to the prototype USM. Vibration amplitude control is employed for speed regulation. The first trajectory following strategy is a step-by-step interpolation. The second strategy is vector decomposition control. Three pulse width modulation (PWM) methods for the exciting voltage regulation are investigated. These methods are compared and verified by several experiments. The key is to keep the phase differences of the three vibration constants and small exciting voltage distortion while the exciting voltages are changed for simplifing the control process and obtaining good control performance. The vector control method has advantages of small trajectory following error, smooth moving and low noise. 展开更多
关键词 MULTI-DEGREE-OF-FREEDOM ultrasonic motor CONTROL
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Discussion on Existing Problems and the Development Trend of Electrical Automation Monitoring System
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作者 Haiming LIU Rumin LIU Lingzhi YANG 《International Journal of Technology Management》 2015年第3期117-119,共3页
With the continuous improvement of industrial automation in our country and the use of high technology, promoted the scientific content of traditional industry. The development of electric automation control system in... With the continuous improvement of industrial automation in our country and the use of high technology, promoted the scientific content of traditional industry. The development of electric automation control system inevitably turn towards a systematic, comprehensive development direction. This article first analyze the present problems in electrical automation monitoring system, analyzes its future development trends, so as to provide some reference for the effective application of electrical automation in the future monitoring system, fundamentally realize the resources sharing. 展开更多
关键词 Electrical automation monitoring system PROBLEM DEVELOPMENT
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A new phenomenon of quantum-dot cellular automata
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作者 曾令刚 王庆康 戴永兵 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第10期1090-1094,共5页
If an external point charge and the movable charges of an isolated quantum-dot cellular automata (QCA) cell have the same polarity, the point charge greatly affects the polarization (P) of the cell only when it is in ... If an external point charge and the movable charges of an isolated quantum-dot cellular automata (QCA) cell have the same polarity, the point charge greatly affects the polarization (P) of the cell only when it is in a narrow band with periodically changing width. The center of the band is on a radius R circle. The ratio of R to the electric charge (q) is a constant determined by the parameters of the cell. A QCA cell can be used as charge detector based on the above phenomenon. 展开更多
关键词 Quantum-dot cellular automata (QCA) Quantum dot Hubbard-type Hamiltonian
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Animal Behavior in a Fully Automatically Controlled Dairy Farm
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作者 Anja Graiff Renate Luise Dorfler +2 位作者 Manfred Hold Jorn Stumpenhausen Heinz Bernhardt 《Journal of Agricultural Science and Technology(A)》 2015年第1期61-67,共7页
As there are increasing numbers of small farms in Germany, it is necessary for them, to keep the workload as small as possible by enhancing the use of automatism. Important as those energetic-technical capabilities an... As there are increasing numbers of small farms in Germany, it is necessary for them, to keep the workload as small as possible by enhancing the use of automatism. Important as those energetic-technical capabilities and features in a modem dairy farm are, the final decision when using automatic machinery depends on the animal itself and its behavior. As a result, all animal-physiological criteria, animal protection and animal welfare have to be taken into consideration. Therefore tests have been done to investigate dairy cattle behavior on suddenly occurring energy failures, fluctuations or postponements due to a load management. The experiments have been taken in four different stables. In each stable, 12 "focus cows" have been selected. Their daily stress response was measured by a heart rate monitor and faecal cortisol metabolites. Video observation showed modifications in behavior, escape or avoidance reactions; pedometers recorded the movement activity. These scientific experiments will demonstrate cattle behavior in situations driven by a power load management, but no statistically significant effects on the usual daily routine are being expected. 展开更多
关键词 Cattle behavior CORTISOL heart rate variability power load management smart grid Germany.
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Free Vibration of Geometrically Nonlinear Functionally Graded Micro-switches under Electrostatic Force and Temperature Change
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作者 Xiaoli Jia Chengbao Feng Kun Tang 《Journal of Mechanics Engineering and Automation》 2015年第1期26-32,共7页
The free vibration characteristics of functionally graded micro-switches under combined electrostatic, axial residual stress and temperature change is investigated, with an emphasis on the effect of geometric nonlinea... The free vibration characteristics of functionally graded micro-switches under combined electrostatic, axial residual stress and temperature change is investigated, with an emphasis on the effect of geometric nonlinear deformation due to mid-plane stretching, the influence of volume fraction profile parameter and temperature change. The micro-switch considered in this study is made of either homogeneous material or non-homogeneous functionally graded material with two material phases. Taking the temperature-dependency of the effective material properties into consideration, the Voigt model is used to simulate the material properties of the FGMs (functionally graded materials). The principle of virtual work is used to derive the nonlinear governing differential equation. The eigenvalue problem which describes free vibration of the micro-beam at its statically deflected state is then solved using DQM (differential quadrature method). The natural frequencies of clamped-clamped micro-switches are obtained. The solutions are validated through direct comparisons with experimental results reported in previous studies. A parametric study is conducted to show the effects of geometric nonlinearity, material composition, temperature change and geometrical parameters for the natural frequencies. 展开更多
关键词 Micro-switch free vibration functionally graded materials temperature change
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The research of controller area network on hybrid electrical vehicle
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作者 吴红星 Song Liwei Kou Baoquan Cheng Shukang 《High Technology Letters》 EI CAS 2006年第2期213-218,共6页
It is of increasing importance to design and implement vehicle networks for transferring information between electrical control units on Hybrid Electrical Vehicle (HEV). This paper presents a scheme of using Control... It is of increasing importance to design and implement vehicle networks for transferring information between electrical control units on Hybrid Electrical Vehicle (HEV). This paper presents a scheme of using Controller Area Network (CAN) technology to realize communication and datasharing between the electrical units on the HEV. The principle and communication protocol of Electrical Control Units (ECU) CAN node are introduced. By considering different sensitivity of the devices to the latency of data transportation, a new design procedure is proposed for the purpose of simplifying network codes and wiring harness, reducing assembly space and weight, improving assembly efficiency, and enhancing fault-diagnose in auto networks. 展开更多
关键词 CAN bus hybrid electrical vehicle vehicle management unit
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Multi-level multi-area hybrid automatic voltage control system and its trial operation in Northeast China Grid 被引量:6
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作者 ZHANG XueMin MEI ShengWei +4 位作者 SU XinYi WANG Gang JIA Wei SHAO GuangHui XU XingWei 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第9期2501-2505,共5页
In order to coordinate automatic voltage control (AVC) systems of a large interconnected system, a multi-level multi-area hybrid automatic voltage control (MLMA-HAVC) system was constructed. This system began its ... In order to coordinate automatic voltage control (AVC) systems of a large interconnected system, a multi-level multi-area hybrid automatic voltage control (MLMA-HAVC) system was constructed. This system began its trial operation in the Northeast China Grid in January 2010, and for the first time in China and abroad it realized automatic close-loop control of multi-area and multi-level interconnected power grid and multi-objective self-approaching optimization in aspects of security, high quality and economic operation. This system has three breakthroughs in theory and engineering application: l) Established the MLMA-HAVC theory to solve multi-objective optimization of large-scale system; 2) proposed reactive power/voltage coordination control method to inhibit or further eliminate regional oscillations; 3) presented advanced state estimation algorithm to guarantee acquisition of high reliability data. This paper summarizes the basic principle of MLMA-HAVC, and reports engineering realization of MI ,MA-HAVC system in tha Northeast China Grid. 展开更多
关键词 hybrid automatic voltage control coordinated control advanced state estimation
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Autonomous energy efficient wheel loader research at TUT
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作者 Kalevi Huhtala 《International Journal of Hydromechatronics》 2018年第1期107-125,共19页
Future worksites will be occupied by different level of automation work machines. How these machines are working individually and how a fleet of these machines cooperates will be in focus of research and development w... Future worksites will be occupied by different level of automation work machines. How these machines are working individually and how a fleet of these machines cooperates will be in focus of research and development work in the future. In this paper the studied off-road vehicle is a wheel loader. It can be controlled manually, remotely or autonomously. The control strategy of autonomous wheel loader is consisting of, e.g., static and dynamic mapping, path planning, obstacle observation and avoidance. In the autonomous machines and also in machines where operator assistance system is active the situational awareness is the key research field. Power management in hydraulic work machines are still active fields of research. Multiple architectures and configurations have been suggested concerning this area. In addition, implemented solutions that consider an entire machine are rarely presented. This paper introduces the research work of the control systems which are minimising the fuel consumption. 展开更多
关键词 energy efficiency autonomous machines hydrostatic drives HSDs mathematical modelling PATH-PLANNING digital hydraulics.
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Research and Implementation of Multi-Point Automatic Synchronization Based on Active Frequency Tracking Control
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作者 Zhang Hui Hu Po 《Electricity》 2014年第4期42-50,共9页
Reliable connection of turbine generators in complex main wiring structures to the power grid through a plurality of switches is a new key problem,referred to as multipoint automatic synchronization(MPAS),in automatic... Reliable connection of turbine generators in complex main wiring structures to the power grid through a plurality of switches is a new key problem,referred to as multipoint automatic synchronization(MPAS),in automatic control systems(ACS).In this paper,different methods of voltage-frequency and phase-difference control are analyzed,and a control methodology based on active frequency tracking(AFT)is presented.Through the establishment of the multi-point automatic synchronization model and the analysis of the governor transfer function with this control method,the important control parameters and automatic process control sequence are summarized.The correctness and effectiveness of the designed methodology are inspected through on-site testing,and the importance of the function and selection of parameters are also explored. 展开更多
关键词 governor system active frequency tracking multi-point automatic synchronization processcontrol sequence automatic control system
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