Abstract:Considering a new power supply-demand relationship for the future power grid, the power supply-demand structure of Jiangsu electric power grid was analyzed, which involved the high penetration of large-scale clean energy integration, the rapid growth of electric vehicles and mass flexible loads of micro-grid. For analyzing friendly interaction among the power suppliers, power grid and loads, a comprehensive benefit assessment model was worked up. Based on the overall benefits of all participants using the benefit assessment model built before, it proposed a pluralistic and friendly interaction system adapted for new power supply and demand. The function architecture includes state awareness, data processing, state visibility and collaborative optimization. Finally, the work of study and practice of the pluralistic and friendly interaction system in Jiangsu power grid was introduced in the fields of implementation mode, interaction strategy and the system's application. This work plays an important role in the enhancement of the interaction between power grid and users, the flexible interactive capability of accommodating the electric power generated by renewable energy and the charging load, and reaches an interactive win-win situation for all parties under the application of energy supply-demand linkage.

Abstract:In order to study power output characteristics and interrelatedness of intensive large-scale wind farms located around coastal areas, the large-scale wind farms sit at coastal areas of Jiangsu were taken as an example and some work was done. Based on the field measurement data of output wind power from the EMS system, active power correlation, probability distributions and the monthly maximum output power among wind farms were analyzed. The fluctuation of wind farms output active power was studied and the impact of output active wind power on the composite load of Jiangsu as well as on peak-load regulation was discussed. This work is important for the utilization rate improvement and dispatching optimization of distributed new energy.

Abstract:For the problem of overheating caused by unevenly heating of high-temperature heating surfaces along the width direction in large coal-fired boilers, a detail study have been performed on the final superheater of 600 MW supercritical coal-fired boiler. Based on the prediction of oxide scale growth model and the heat deviation calculation, the influence of the oxide scale growth on tube temperature was analyzed. Results show that the tube temperature increases with the growth of oxide scale, which would lead to local temperature over-run of the superheater tube and decline of creep rupture life, thus the effect of oxide scale on tube temperature should be considered in the heat deviation calculation.

Abstract:The current develop tendency to informatization and intelligence of power grid puts forward stricter requirement on metering technical supervision. It is very important to evaluate the technical supervision work accurately and objectively, but most traditional evaluation on metering technical supervision is manual and lack of effective tools to assess the indicators of key nodes using existing data. This article proposes a fuzzy comprehensive method, which employs calculated entropy weight of key indices from the Electric Energy Information Acquisition System to build an indicator architecture and then obtains an accurate evaluation and ranking result of different technical supervision work according to the fuzzy comprehensive method. The proposed method effectively enhances the discrimination of technical supervision work and improves the accuracy of corresponding evaluation.

Abstract:Since 2009, hundreds of millions of smart meters have been installed nationwide. State Grid Corporation of China manages the asset by centralized inspection in large scale. Meanwhile, a system called Power User Electric Energy Data Acquire System was built up to monitor the operation status of these meters. Therefore, vast amounts of life-time data of the meters can be obtained from the centralized inspection system as well as the data acquire system. This paper proposed a way of establishing the connections between fault data and inspection data by training neural network under MATLAB environment. And then the possibility and effectiveness to obtain fault information of smart meters in advance by data mining is discussed, to provide an alternative way of quality control of smart meters.

Abstract:This submission proposes a multi-target compounded AGV (Automated Guided Vehicle) scheduling system model based on the driving distance, the task waiting time and the task priority. The model's performance indicator can be optimized automatically through adjusting the weight coefficients of different factors. In order to ensure the maximum efficiency of AGV task execution, the shortest path search strategy is designed according to the A* algorithm. The AGV scheduling model is tested in the electric power metering digital workshop. The results show that the proposed method has good adaptability and replicability.

Abstract:Demand-side response is beneficial to both the electricity grid companies and power consumers. This paper introduces the concept of demand-side response,and studies the system structure and electricity strategy of home energy management under the condition of demand-side response. And then, the existing electricity strategies are classified according to RTP, TOU, temperature control consideration and integrated energy, and the shortcomings and advantages of these strategies are summarized. Finally, some advices are given for the future development direction of the home energy management.

Abstract:In order to obtain the accurate and rapid positioning of power oscillation source, based on the data of wide area measurement system (WAMS), a forced oscillation source location method by phase identification is presented. According to the conversion property of oscillation energy and phasor relationship, it is proposed that whether the source of the disturbance is located on the generator is determined by judging the absolute value of the phase difference between the generator rotor frequency and the output of electrical power. Utilizing the TLS-ESPRIT algorithm to extract the frequency and calculate the corresponding phase. The calculation results of examples show that the presented method to locate the disturbance source is feasible and effective, which is concise and intuitional and reduces the complexity of power system on-line detection and analysis.

Abstract:The photovoltaic output power is obvious random, fluctuant and intermittent, which has certain extent of negative effects on power system. TOU method is adopted to guide the consumers to change the power consumption way. And the load profile is regulated to track PV power output and improve the correlation of them, which leads to increment of PV capacity credit. TOU method is introduced in the IEEE-RTS79 system with photovoltaic generation to simulate the probabilistic production. And the reliability of the system before and after using TOU method is evaluated with taking into account of stochastic fluctuation of load and PV output. Then the reliability indicator is calculated with sequential Monte Carlo algorithm, and PV capacity credit is obtained with secant method. The result verifies the effectiveness of TOU method on improving PV capacity credit.

Abstract:The operation information of intelligent protection equipment is changing during the equipment's life cycle, so it is difficult for managers in the intelligent protection equipment R&D or application enterprises to grasp the whole equipment information, not to say the efficient usage of equipment. According to the characteristics of intelligent protection equipment, the feasibility and advantage of the application of two-dimensional code technology were discussed. Finally according to the application requirements and based on the mature two-dimensional code technology, intelligent protection equipment management system was designed and developed on the basis of the existing equipment, gaining a quick access to equipment information and starting the approval process through the mobile terminal or computer. The practice shows that intelligent protection equipment management system by using two- dimensional code technology is superior and worth to be popularized.

Abstract:Traditional micro-grids in marine areas have the disadvantages of single energy, less participating in energy regulation of flexible loads, and simple grid structure. Against these disadvantages the functional architecture of multi-energy micro-grid in marine areas was designed in this paper. The micro-grid made full use of the characteristics of clean energy such as wave, wind and solar, and took advantage of VSG technology, to improve the stability of distributed energy generation. Energy router was treated as the control center of the micro-grid to realize controlling source-load interaction by adjusting flexible loads such as seawater desalination device and P2G device. Implementations of energy router, VSG, source-load interaction, CPS in micro-grid in marine areas were studied and applied to the micro-grid demonstration project in Cheniushan island.

Abstract:The existing communication object model of PMU cannot meet the requirement of computing the frequency variation or provide safe routable communication protocol. So in this paper, a PMU information model based on IEC 61850-90-5 is proposed after analyzing the similarities and differences between IEC 61850-90-5 and IEEE C37.118. The communication service used for synchronous phasor exchange is studied according to 90-5 protocol. And new transmission and control blocks are configured to improve the existing PMU object model. As a result, this method improves transforming ability from IEEE C37.118 to IEC 61850-90-5, and achieves better performance of synchronous measurement. It also lays the theoretical foundations for establishing a unified communication model between PMU and master station.

Abstract:In the real practice applications, classical composite load model (CLM) is widely used and developed in the power grid. In this paper, CLM considering frequency characteristics was interested in. With instantaneous sampling data of alternating current voltage and current, the CLM's parameters were identified by load parameter identification strategy based on measurement-based method ant colony algorithm with stronger capability of global optimization. Through simulation and calculation, the impact of sampling data with different length of time on parameter identification results of load model was comparatively analyzed. The impact of sampling data with the same time length on the curve fitting results of load model was also analyzed.

Abstract:This paper presented an economic optimization model for micro-grid considering islanding constraints. In the model, grid-connected operation was the master problem taking minimizing the operation costs of micro-grid as the target, and islanded operation was the sub-problem taking minimizing the mismatches between power source and load of micro-grid as the target. Power source cutting 1 and load cutting 2 were generated to connect the master problem and the sub-problem, and were revised to optimize model's economic indexes. Considering the complication of model's target function and constraints, linearization technology was used to speed up the calculation. Some numerical simulations have demonstrated the correctness of the proposed economic optimization model for micro-grid.

Abstract:Capacitor voltage transformer (CVT) is the main equipment with functions of measurement, protection, and communications in power system. The stable operation of CVT is very important to the security of grid. However the CVT's failure occurs sometimes and it needs much manpower and many resources to maintain. According to the field operation experience of CVT, it is still difficult to give the real-time, accurate and effective condition monitoring to the CVT. So the paper introduces the common failure type and mechanism of CVT's components firstly, and then describes and analyzes its existing condition monitoring methods in detail. At last, the paper gives the prospection to the development trend and direction of the condition monitoring of CVT.

Abstract:The paper proposed a new fault location unaffected by transmission line parameters (TLPs) to eliminate the errors of the existing one caused by TLP variations. To get the new fault location, firstly the unit impedance expression is derived based on the lumped parameter circuit model and the basic principle that at faulty point voltages calculated from both terminals can be equal. Then an easy location equation is got by eliminating the unit impedance based on the sequence component method, so that the fault point can be also located when the values of TLPs are unknown. Simulation results show that the new fault location where the faulty point is solved without iteration and search is reliable, effective, and precise, and has a good practical value.

Abstract:Automated warehouse is the logistics transit center of super-large-scale electric energy meter automatic verification system, which plays the key role in storage, transshipment and verification of the meters. This paper proposes an optimization strategy of freight flow on automated warehouse and gives the calculation and analysis of the flow of the key points. The results show that this strategy can significantly decrease the pressure of the main freight transfer line and improve the speed of freight allocation under the premise of ensuring the ability of in-out stock.

Abstract:Life Cycle Cost (LLC) management takes long-term economic benefits as starting point, and the whole process from design to retirement is fully considered in order to minimize costs. The development of LCC theory is analyzed firstly in this paper. Then, combined with condition-based maintenance strategy, the LCC model and sensitivity analysis of the key equipment such as transformer, switch, high voltage cable are studied. Finally, the key data in the operation and maintenance process is identified to give reference to power system life-cycle management system building.

Abstract:According to the icing problem of overhead transmission lines, short circuit current method is proposed to solve it. A flexible connection device of the ground wire for de-icing is also developed for connecting and flowing between the conductors and ground wires contingently. The developed device can be utilized to melt the ice in any section of the transmission tower, and can be installed or disassembled on the tower by the construction personnel. The connection device avoids the risk of online operation and has the features of light weight, good portability, easy operation, and high versatility, etc.

Abstract:Taking use of the equipment act information, fault record data and setting values of protection equipment, the reason for the override trip of the transformer's backup protection is found. The paper has described the accident process. Because of damaged line protection and extortionate bus voltage, the compound voltage locking unit of the backup protection of the main transformer low voltage side refused to act, and the override trip of the backup protection of the main transformer high voltage side took place. In order to prevent accidents like this, improvements of the existing main transformer backup protection were proposed, that is revising action logic and adding time-based low voltage unit whose action equations had been given in the paper.

Abstract:Electrical joint compound grease is widely used in metal connections of high-voltage electrical equipment. In this paper, heat defect of strain clamp of 35 kV overhead line is firstly analyzed, and then the influence of electrical joint compound grease on the heat defect is studied. The result shows that, large test current flows through the aluminum contact surface when two aluminum clamps contact well while it flows through connecting bolts when the connection is undesirable. Therefore, it is recommended to improve construction technology and select proper electrical joint compound grease in order to avoid heat defect of electrical equipment.

Abstract:A mal-telecommunicating problem is occurred in a 220 kV substation. After comparing all the possible factors, instead of the traditional reason, the fault is caused by the too much remote communication signals which lead to the overflow of the address message and the overlap of the signals. This analysis provides a new method to mal-telecommunication. For this failure, after considering the economy and maneuverability, deleting or combining redundant signals is chosen as the solution, which improves the accuracy of the remote communication data as well as the security and stability of the automation system.

Abstract:In this paper, a special case of bus differential protection caused by 110 kV outgoing line fault in 220 kV substation is analyzed. It is found that the cause of the differential protection action is the current waveform distortion through the detailed analysis of the protection action. And according to this circumstance, the differential protection improvement measures and the method to handle such accident are put forward in the end of the paper.

Abstract:This paper analyzed the defects of the independent evaluation system on coal-fired unit, introduced the concept of the energy-saving and emission reduction performance evaluation, elaborated the online evaluation model of comprehensive performance and the framework design of the real-time evaluation system. Finally the advanced application of the system on competition comment, team benchmarking, the promotion of industry benchmarking and the supervision of government department was presented.

Abstract:According to the simulation calculation model, the desulfurization agitator of USC unit was analyzed by the static simulation. With the test results of simulation welding specimens, fatigue simulation analysis has been performed on the condition after welding repair , and the applicability of the welding process was verified.

Abstract:With the problem of inside guide wheel falling-off from west side of tail-end of the running slag conveyor in No.1 unit of Xinhai power generation company, professionals decided to reduce the load and isolate part of the boiler bottom seal to replace the inside guide wheel online. In a pinch, short-time destroying the boiler bottom seal counld be performed. To ensure the safety of staffs and devices, the scheme of operation and inspection was carried out with preliminary adequate planning and preparation. With the well-controlling of operation parameters, the implementation process would be achieved, which could be serve as references for the repair scheme establishment of coal-fires boiler with similar slagging type.