Table of Content

25 August 2015, Volume 48 Issue 8

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Column of Flue Gas Dust Removal

Research and Development of Enhanced PM2.5 Collection Device Installed in the ESP Inlet Hood

LIU Hanxiao, LI Jianguo, YAO Yuping, SHEN Zhiang, PAN Minxing, GUO Feng

2015, 48(8):  1-7.  DOI: 10.11930.2015.8.1

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Though limited by its application occasions, the PM2.5 collection enhancement technology is still one of the most economic and effective PM2.5 capture methods for the coal-fired power plants. With the CFD software, the effect of three-layer perforated plate in ESP inlet hood on different polarity particle mixtures is analyzed. Particularly, the effectiveness of turning vane, power-on turning vane and straight panel on different polarity particle mixtures are calculated respectively and the air flow distribution patterns are verified. In this way, the enhanced PM2.5 collection device installed in the ESP inlet hood is developed with sonic soot cleaning functionality equipped together. This device has been used successfully in the ESP of Guodian Jianbi Power Plant Boiler No.14, with 1 000 MW capacity. Significant improvement is observed in the application practice.

Experimental Study on the Effects of Agglomerator and New ESP Technologies on Particulate Removal Efficiency

WANG Dongge， ZHU Fahua， YI Yuping, LIU Zhi, LI Xiaoming， MENG Lingyuan，

2015, 48(8):  8-12.  DOI: 10.11930.2015.8.8

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In this paper, the effects of agglomerator and some new ESP technologies(such as mobile electrode duster and high-frequency power supply) on particulate emissions are studied for a 135-MW coal-fired power generating unit. The results show that with the agglomerator being turned on, the concentrations of the total particulate matter and PM2.5 are reduced by 23.93%~40.16% and 39.54%~55.21%, respectively, while with the mobile electrode in operation, the concentrations of the total particulate matter and PM2.5 are decreased by 25.46%~56.59% and 11.68%~33.18%, respectively. Moreover, with the high-frequency power supply being turned on, the concentrations of the total particulate matter and PM2.5 are decreased by 12.81%~21.27% and 22.11%~43.11%, respectively. This experimental study indicates that the agglomerator and the new technologies can significantly improve the collection efficiency of the electrostatic precipitator, especially for the emission reduction of the PM2.5 particles. It is certain that they will play an important role in the innovation and upgrading of dust removal devices.

Study on Application Conditions of Wet Electrostatic Precipitators in Coal-Fired Power Plants

ZHANG Huadong, ZHOU Yuxiang, LONG Hui

2015, 48(8):  13-16.  DOI: 10.11930.2015.8.13

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In recent years, wet electrostatic precipitators(WESPs) have been rapidly developed in China. Due to the lack of the common understandings about WESP in the industries and practical experience, it is necessary to explore the application conditions and equipment selection of WESP by learning from the foreign experience. Based on the investigation of WESPs in domestic and foreign coal-fired power plants, the development and application of WESPs are analyzed comprehensively, and the importance of WESP in the entire flue gas treatment system is presented. Finally, some suggestions on the application conditions of WESPs are put forward.

A Case Study of Economic Comparison between Low-Low Temperature Dust Removal Technique and Electric- Baghouse Combined Dust Removal Technique in the 300-MW Unit Improvement

WANG Jianfeng, LI Yan, ZHANG Yang, ZHU Yue

2015, 48(8):  17-19.  DOI: 10.11930.2015.8.17

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In this paper, the technical economic performance of low-low temperature electrostatic precipitator(ESP) and combined electro-bag filter are compared for the improvement of the 300-MW coal-fired boiler of a power plant. The comparison result shows that the low-low temperature ESP has the advantages of better adaptability to different flue-loads, more energy saving, emission reduction and no solid emissions. The installation of low-low temperature ESP will take more effort than the combined eletro-bag filter although the investment expenses of these two technologies are approximately the same. Therefore the unit costs of low-low temperature ESP is lower than that of the combined eletro-bag filter.

Commissioning Test and Tuning of 600-MW-class Wet Electrostatic Precipitators

YANG Qunfa, HOU Jianxiong, CHEN Guanming

2015, 48(8):  20-26.  DOI: 10.11930.2015.8.20

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Recently, there have been a lot of new WESPs commissioning in spite of little practical experience. Therefore, it is necessary to summarize the tuning and operating experience of WESPs. Through the analysis on the problems coming up in the 600-MW class WESP of Zhuhai Jinwan Power Plant in Guangdong Province, the corresponding technical improvement and operation adjustment measures are put forward, which ensures smooth WESP commissioning and eventually super low emission from the generation unit is achieved.

Operation Optimization of Bag House and Ageing-Tendency Management of Filter Bag for 300-MW Thermal Power Units

WANG Fangyong

2015, 48(8):  27-32.  DOI: 10.11930.2015.8.27

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Bag houses are commonly used in the power plants in China. Extending the service life of filter bags is crucial to reduce their operating costs. This article analyzes the factors that affecting the service life of filter bags for the bag house in a power plant, and presents the ways to extend the service life of filter bags by optimizing operation, improving maintenance conditions and technical upgrading. In addition, the article also gives advices on ageing-tendency management for filter bags, in which the experience accumulation is earned for bag house maintenance and management.

Analysis of Dust Removal Effect in Wet-FGD System and its Efficiency-Enhancement Techniques

WEI Hongge, YE Weiping, CHAI Lei, ZHU Yue

2015, 48(8):  33-36.  DOI: 10.11930.2015.8.33

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Through the test on dust removal efficiency of Wet-FGD, the major contributing factors are studied, in which FGD exhibits outstanding performance in dust removal under conditions of higher inlet dust concentration. Presently, the comprehensive dust removal efficiency reaches as high as about 50%. Meanwhile, under normal conditions, the mist contents in FGD’s outlet flue gas are higher than the designed value, hence the solid particles in the mist is one of the key factors which leads to the low dust removal efficiency. Therefore, several enhancement techniques are proposed to improve the dust removal efficiency of FGD system such that the collaborative dust removal can be realized in FGD system, which can also inspire new ideas for the subsequent FGD retrofit work.

Power System

Acquisition System of Wavelet Energy Spectrum Entropy of Transformer Vibration Signal Based on DSP

TAO Xinmin, LI Zhen, ZHANG Yue

2015, 48(8):  37-41.  DOI: 10.11930.2015.8.37

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As the vibration signals of the transformer body contain abundant fault information, using vibration method for on-line monitoring of transformer operation has become one of the research emphasis of transformer fault diagnosis. Based on wavelet transform and information entropy theory, the wavelet energy spectrum entropy of the transformer vibration signals are selected as characteristic signal for fault diagnosis. Using TMS320F2812 as core DSP chip, an acquisition system of wavelet energy spectrum entropy of transformer vibration signal is designed and developed. The results show that the wavelet packet energy spectrum entropy between normal operation and fault operation are different. Therefore, this method can effectively extract transformer vibration signal characteristic value and provide powerful basis for subsequent fault diagnosis.

Research on the Hydrophobic Nature of 110 kV Composite Insulator Surface

ZHAO Xinze， WANG Lei， XIANYU Wenling， YANG Zhicheng， FU Zhicheng，

2015, 48(8):  42-45.  DOI: 10.11930.2015.8.42

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In order to study the relationship between environmental factors and composite insulator surface hydrophobic characteristic, composite insulator aging process in different conditions is simulated by spray test and immersion test. The surface hydrophobic nature is analyzed by using dynamic contact angle method under different spray time and acid corrosion conditions. Surface morphology of the samples are analyzed in detail by scanning electron microscopy(SEM). The experimental results show that the surface hydrophobic gradually weaken, and may even be completely lost by long exposure to dirty wet environment. Acidic environment have much greater impact on the surface hydrophobic than neutral or alkaline environment because acidic substances have greater influence on the surface compare to neutral or alkaline substances.

Impact of Probability Distribution Model Selection on Extreme Value of Conductor Ice Thickness

YANG Jialun, ZHU Kuanjun, LIU Bin, YIN Quan, YE Chengzhi, LI Xingyu

2015, 48(8):  46-52.  DOI: 10.11930.2015.8.46

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The selection of different probability distribution models can influence conductor ice thickness for specific return period. This paper discuss 3 typical models, namely Pearson Ⅲ distribution, Generalized extreme value distribution and Generalized Pareto distribution. The model applications on historical ice data from Nanyue Mountain weather station of Hunan province are analyzed. The results are helpful for final design of overhead transmission lines during terms of conductor ice thickness calculation.

A Computing Platform for Distribution Network Reconfiguration Based on 8 Intelligent Algorithms and Its Performance

GAO Yuanhai, WANG Chun

2015, 48(8):  53-60.  DOI: 10.11930.2015.8.53

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In order to seek an intelligent algorithm that is suitable for solving the distribution network reconfiguration issue, a computing platform which employs eight population-based intelligent algorithms is constructed. In the platform, for different algorithms, the distribution network reconfiguration model and the basic loop search module are completely consistent, with the parameters such as population size and elite number being identical. The basic principles and calculation procedures of the eight algorithms are given. The sensitivity of the algorithm parameters is tested, and the performance of the eight algorithms is compared using IEEE 33-bus system. In addition, the adaptability of the algorithms is further compared using the IEEE 16-bus and PG&E 69-bus test systems. The results show that Stud GA is the most suitable algorithm and BBO comes the second in terms of the average objective function value, the probability of converging to the best solution, the computation time and the adaptability to the systems of different scales, and the other algorithms have inconsistent performance in different test systems. Stud GA is a suitable algorithm for solving the distribution network reconfiguration issue because of its advantages of simple operation, few parameters, short computing time, and high probability of converging to the optimal solution.

A Revised Branch-Current-Based State Estimation Method for Weak Looped Distribution Network

ZHANG Zhanlong, MA Haitao, SHI Weicheng, GAO Yajing, WANG Qian, ZHAO Xiaoxu

2015, 48(8):  61-66.  DOI: 10.11930.2015.8.61

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Along with the development of distribution-network automation, the distribution system management has become a hot spot for study, and the state estimation of distribution network is a very important part of the study. In this paper, the meshed distribution network is changed to a radial distribution network by splitting the node in the loop. In order to satisfy the observable condition for distribution state estimation, a couple of load peso-measurements are added to the split nodes, which are obtained through the power flow calculation. Based on above-mentioned processing, the state estimation for meshed network is converted to the state estimation for radial distribution network. Numerical analysis has proved the rationality and effectiveness of this method, which can be realized by partly modifying the original algorithm program of the current-based state estimation, and thus has a good practical application value.

Data Conversion of Two-Terminal DC Line Model between BPA and PSS/E Based on Open Data Model

MA Yisong, WU Zhigang

2015, 48(8):  67-72.  DOI: 10.11930.2015.8.67

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In order to convert two-terminal DC line model between BPA and PSS/E, the line data, control mode and calculation formula of two-terminal DC line model between two software are analyzed first. A method to eliminate the differences of reactive power loss in converter stations by modifying reactive power via shunt compensation is proposed. A data conversion program is developed based on Open Data Model(ODM). The simulation results on simple 2DC 9-bus system and practical large-scale regional grid show the validity of proposed method.

Design and Research of new Tangent Tower for Transmission Line with 500 kV/220 kV Four Circuits in the Same Tower

XIE Fang, FENG Bing, GUO Yong, YE Yin

2015, 48(8):  73-79.  DOI: 10.11930.2015.8.73

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Traditional design of tangent towers for transmission line with 500/220 kV four circuits in the same tower has conflict between line corridor and tower material indices. Based on the technical-economy comparison, a new type of tangent tower, namely Cross-body Tower, is proposed. In proposed design, two phase conductors for 220 kV cross through tower body, which eliminate the effect of 220 kV line on the width of the corridor. The total number of cross-arms is still 5. The electrical performance, electromagnetic enviornments, linear and non-linear of structure and modal of proposed design are analzed in detail. The results show that new design complies with specification requirement and has rational structure and satisfactory dynamic performance. The technical and economic comparison results also indicate that proposed design has many advantages compare to classic design, especially in economically developed region with restricted transmission line corridor.

Study on On-Line Monitoring Index of MOA

CAO Hongliang， YANG Zhongjiang， REN Jing, JIANG Su， LI Pengfei，

2015, 48(8):  80-85.  DOI: 10.11930.2015.8.80

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The metal oxide arrester (MOA) plays a very important role in the safe operation of power systems. In order to find an appropriate indicator that can reflect the degradation of MOA, a comparative study is made through Matlab simulation on the existing fundamental harmonic resistant current and the third harmonic resistant current. The result shows that the resistant current with fundamental harmonic component and the third harmonic component produced by the fundamental voltage can better reflect the degradation of MOA. In addition,based on Fryze’s power definition, a simple algorithm which can calculate the fundamental harmonic current produced by the fundamental voltage is proposed and its efficiency is validated by simulation.

Contamination Accumulating Features of Composite Insulator of ±500 kV Xingren-Baoan HVDC Transmission Line

ZHENG Qiuwei, LIU Huagang, ZHOU Jianming, YANG Shuai, YU Jianhui, ZHOU Wenjun

2015, 48(8):  86-91.  DOI: 10.11930.2015.8.86

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Under the influence of electrostatic dust collection effect, the insulator contamination of HVDC transmission line is heavier than that of HVAC and has a higher risk of pollution flashover. Study of the contamination features of insulators for DC transmission line is conducive to the external insulation configuration of power system as well as the prevention and control of pollution flashover, and can also ensure the safety operation of power system. This paper investigates the contamination features of insulators by collecting the contamination on the surface of composite insulators of ±500 kV Xingren-Baoan DC transmission line and by testing the ESDD under the laboratory environment. The experimental results show that the contamination on the surface of composite insulators of ±500 kV Xingren-Baoan HVDC transmission line is relatively light and the ESDD is below 0.025 mg/cm2; the contamination on the surface of insulators is influenced by the local pollution sources and the DC polarity has no effect on the contamination of insulator strings. The ESDD on the surface of composite insulator string appears U-shaped curve, and 63% of the sample’s ESDD in the upper surface is greater than that in the lower surface and the small insulator sheds have the worst polluted condition among different insulator sheds arrangement modes. Obvious differences are observed between DC and AC transmission lines in contamination features of composite insulators.

Lightning Discharge Character of Shunt Gap Used for 220 kV Glass Insulator String

LI Te, ZHOU Guoliang, LIU Yan, XIE Cheng, ZHANG Ximing

2015, 48(8):  92-96.  DOI: 10.11930.2015.8.92

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Shunt gap for insulators is beneficial for protecting insulators and improving power supply reliability. However, there exist failure examples during shunt gap application. Lightning discharge test of shunt gap with typical geometry parameters for 220 kV glass insulators is performed to investigate relationship between geometry size and protection effect. The U50 discharge voltage of the gap is found and the arc path is analyzed. Possible explanation of protection failure is proposed. Test results indicate that shunt gap protection effect could be improved with smaller value of Z/Z0 and with larger value of Xc and Xp. Protection effect stabilizes when the value of Z/Z0 is smaller than 0.875. Arc exists at both sides of the gap under the lightning voltage. The arc bends to the insulator by the radial electrical field, which might be the main reason of protection failure under U50.

Research on Superior Combined Forecasting Method of Short-Term Bus Load and Its Application in Chengdu Grid

CHEN Wu, XIAO Xianyong

2015, 48(8):  97-103.  DOI: 10.11930.2015.8.97

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Short-term bus load forecasting is the important premise for formulating overhaul plan, determining the annual operation mode and optimizing the load change and state estimation, and is very important for energy-saving generation dispatching and lean management of safety operation. In order to solve the shortcoming of the single forecasting method, a new superior combined forecasting method is proposed in this paper. According to the gray correlation index, point prediction accuracy index and interval forecasting effectiveness index in the sample interval and prediction interval, a series of concepts of comprehensive effectiveness of the forecasting method are introduced. By using the variance and covariance method, the weight coefficient of corresponding model is calculated. A case study of the 110 kV bus load in Chengdu grid shows that the proposed combined method is effective with high accuracy and stability.

Research on the Seriation of the Expanded Diameter Conductor with Less Strand of Inner Layer

WAN Jiancheng, DONG Yuming, SI Jiajun, LIU Long, LI Feng

2015, 48(8):  104-109.  DOI: 10.11930.2015.8.104

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Expanded diameter conductor with less strand of inner layer is chosen as the research object in this paper. By utilizing static calculation software developed by China Electric Power Research Institute, the static stability analysis on expanded diameter conductor adopted in previous projects are performed. The purpose of the research is to investigate maximum diameter under the same diameter expand ratio or maximum diameter expand ratio under the same diameter. Taken the 25％ rated tensile strength as the critical tensile, the ladder diagram of static and economic of the expanded diameter conductor under different diameter expand ratio is achieved. According to analysis results, the expanded conductor adopted in previous projects meet safety requirement. The analysis results can be used in application of expanded diameter conductor in future.

Generation Technology

Case Study on Trouble-Shooting of Rotating Machinery Vibration Problems in Power Plants

ZHANG Xueyan, ZHANG Weijun, GE Xiang, YANG Qing

2015, 48(8):  110-116.  DOI: 10.11930.2015.8.110

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n this paper, the case analysis on the vibration problems and their trouble-shooting for some steam turbines, generators, the driving motor of condensate water pumps and raw gas booster fans conducted in the past few years are presented. The analysis illustrates the actual application and effects of vibration fault diagnosis and control techniques. These faults involve bearing failure, generator dynamic inter-turn short circuit, structure resonance and unstable mass unbalance. In each case, the comments on the conclusion of diagnosis are put forward for reference.

Cause Analysis on Burner Burnout and High NOx Emissions after Low-NOx Combustion Retrofit for Pulverized Coal Boilers

LU Jun, XU Dangqi, ZHANG Guangcai, NIE Jianping, ZHOU Fei, XUE Ning

2015, 48(8):  116-120.  DOI: 10.11930.2015.8.116

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Taking a coal-fired power plant as an example, after low-NOx combustion retrofit in Boilers 1 and 2, the problem of burner burnout in the two boilers arises and the NOx emissions from Boiler 1 are about 100 mg/Nm3 more than those from Boiler 2, which endangers the secure operation of the boilers and the normal commissioning of the denitration equipments. Therefore, the cause analysis on these problems is made from the aspects of retrofit design, equipment manufacturing and operation modes. The analysis figures out that: (1) in the low-NOx combustion retrofit design for Boiler 2, coal type changes are not taken into account, only the routine measures for combustion stabilization are taken and the surrounding air damper opening degree is small, which leads to local high temperatures in the burner zone and coal powder accumulation and combustion in the primary air pipes caused by burner anti-wear ceramic shedding. (2) during the burner manufacturing of Boiler 1, the sealing plates between the burner nozzles are not welded following the design requirements. The coal powder is brought back to the burner separators by negative pressure reflux and burned on the separators, which results in burner burnout. Meanwhile, the gaps between the burner nozzles are not sealed, causing serious auxiliary air leakage and reducing the effects of air staged combustion, which leads to high NOx emissions. Based on the above analysis, the improvement is carried out, thus the problems existing in Boilers 1 and 2 are solved effectively. The improvement can provide guidance on solving similar problems for other power plants.

Transient Analysis of Single Feedwater Pump Trip in AP1000 Nuclear Power Plant Rated Power Operation

CHENG Xueqing, YAN Peifu, FU Yinjun, GU Xianqing

2015, 48(8):  121-125.  DOI: 10.11930.2015.8.121

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The AP1000 nuclear power plant adopts three electric pumps of 33.3% capacity with no standby pumps to provide feedwater during rated power operating. Through the stable feedwater and steam flows equilibrium calculation under 100% and 70% rated power conditions, it is verified that in case of one pump trip, the remaining two pumps can maintain power plant operation at 70% rated power. Based on the analysis on the simulation results of single feedwater pump trip transient condition established in CENTS program it is verified that there are no needs for rapid power reduction under this transient condition. The reactor power automatic control and the steam bypass systems can manage to maintain the average temperature of the primary loop within the allowable range while the steam generator water level does not drop to the low-low water level which would cause reactor shutdown. These results are critical to AP1000 nuclear power plant commissioning and operation.

Application of Coal Burner Based on Less Oil Ignition Technique in 1 000-MW Units

LI Jing

2015, 48(8):  126-129.  DOI: 10.11930.2015.8.126

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Regarding the existing problems of large oil consumption during boiler startup, shutdown and stable combustion processes in the two 1 000-MW units of Xuzhou China Resources Power, the coal burners are modified with double-strength less oil ignition technique and the associated auxiliary system is designed. By comparing the oil consumption of large oil guns during startup, the reliability and economic performance of the double-strength less oil igniting system are verified. In addition, the problems of less oil burner wall overheating and ignition failure during the burner operation are also analyzed, and the optimization measures are put forward.

Application of Swirl Spray Technology in 464 000-m3/h Wet Flue Gas Desulphurization

LIU Dingping, LU Peiyu

2015, 48(8):  130-134.  DOI: 10.11930.2015.8.130

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In order to solve the problem of low desulfurization efficiency caused by the uneven flow field, small gas-liquid contact area and short contact time in the mass transfer between flue gas and slurry in the tranditional absorption tower, the efficient in-depth desulfurization with swirl spray technology is proposed, which makes full use of the two-phase spray for ultra-fine atomizing and achieves the goals of improving desulfurization efficiency and saving energy. This technology is applied in the desulfurization modification project of a power plant with the flue gas volume of 460 000-m3/h, that is, a slurry swirl spraying layer is added to the original absorption tower. The measurement results show that the desulfurization efficiency is increased by about 6.5% with the outlet SO2 mass concentration lower than 20 mg/m3. In addition, the spraying layer and the swirl spraying layer can be adjusted according to the sulfur contents in the coal to save the system energy consumption.

Comparative Study on Effects of Large Condensate Pump Improvement with Permanent Magnet Speeding and High-Voltage Frequency Conversion Technologies

HOU Jianxiong, YANG Qunfa, HE Ganbiao

2015, 48(8):  135-140.  DOI: 10.11930.2015.8.135

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In recent years, the condensate pump improvement with high-voltage frequency conversion technology has been in fast-growing, and the new technology of permanent magnetic speeding is getting increased attention. In this paper, the comparative study on the effects of condensate pump improvement with permanent magnet speeding and high-voltage frequency conversion technologies is conducted to provide a reference for technical selection in the large condensate pump improvement. According to the practical operation and research, two power plants with units of similar unit type, capacity and operational lifespan are selected to analyze the energy saving effects, economic performance, reliabilities and investment benefits of the improvement. The study concludes that in the improvement of large condensate pumps, the permanent magnetic speeding technology outperforms the high-voltage frequency conversion technology in terms of reliability, while in the aspects of energy saving and investment benefits, the latter one outgoes the former one.

Impact Analysis of Power System Fault Inside Power Plant on Power Supply Switching Mechanism

LI Zifeng

2015, 48(8):  141-145.  DOI: 10.11930.2015.8.141

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High speed power supply switching equipment is based on assumption of same phasor angle between operation and backup voltage. However, the assumption is not satisfied when fault happens in the system. The impact of fault scenario on power supply switching mechanism is analyzed. The fault analysis during two-phase grounding fault is conducted which shows different phase angle between operation and backup source voltage. The practical bus bar residual voltage during fault is also analyzed. Because of difference between practical and theoretical value, high speed switching may not be successful. Some advice related to high speed switching device settings are given with consideration of possible electric system fault.

Information and Communication

Analysis and Simulation of PLC Channel Noise

XIE Zhiyuan, CAO Wangbin, YIN Chengqun, WEI Jiahong, BI Tingting, JIN Huiying

2015, 48(8):  146-149.  DOI: 10.11930.2015.8.146

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Complex noise is one of the main reasons for hindering the development of power line communication technology. Accurate noise simulation is important for the further development of power line communication. The noise measurement circuit is built and the channel noise is measured in this paper. The measured channel noise is analyzed with Fourier transform and time-frequency analysis, and the sine components of three channel noises are obtained. Finally, three PLC channel noises are simulated by superposing different frequency sine waves. The experimental results show that the simulated channel noise and the measured channel noise have high consistency.

Safety Analysis of Industrial Control System and Improvement of Communication Protocol Design

ZHANG Bo, ZHAO Ting, XU Xingkun, ZHAO Jinwen

2015, 48(8):  150-154.  DOI: 10.11930.2015.8.150

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Due to the increase of industrial control system(ICS) security accidents, cyber security in ICS has been greatly concerned in recent years. However, the research on cyber security protection still remains in the theoretical stage. A prevention measure that can be rapidly built and can reduce the key risks is urgently required. In this paper, a communication model of ICS is firstly established. Based on the model, the security risks and threats of ICS are in-vestigated, and the top urgent and critical security needs are clarified. Moreover, a corresponding security enhancing scheme is proposed with the system function and efficiency unaffected. Based on the one-way identity authentication and integrity checking of the key communication messages and combining with the timestamp checking mechanism and the registration mechanism, the proposed scheme is proved to be able to resist the camouflage, tampering, replay attacks and other common attacks, which can satisfy the system security requirements.

Analysis on Intelligent Matching Technology of Main & Spare Channel Information of Smart Grid Power Dispatching Automation System

PENG Zhiqiang, ZHANG Xiaoyi, YOU Haoyun, LUO Lihua

2015, 48(8):  155-160.  DOI: 10.11930.2015.8.155

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In order to improve the data communication reliability and the data channel redundancy of smart grid power dispatching automation system, the main & spare channel for gathering and transmitting information is applied in the today’s power system, which consequently leads to asynchronous between dispatching automation system and receiving frequency. A new method is presented in this paper, which can intelligently match the power dispatching automation system with the main & spare channel information. The interactive communication message between power dispatching automation system and substation is obtained through network monitoring. The intelligent alignment algorithm is used to compare such communication protocol parameters as remote state, telemetry, SOE, remote control and remote adjustment, and the alarm event is outputted timely according to the compared result. The proposed method is effective in monitoring the quality of main & spare channel communication and detecting the channel abnormalities, and can greatly improve the efficiency of the dispatching automation system.