Abstract:In order to meet the peer-to-peer communication demand of distributed services of regional protection and control system and to realize the peer-to-peer communication mechanism of protection and control service between substations, the network topology for realizing peer-to-peer communication based on Multi-Service Transfer Platform is studied. At the same time, the network topology for peer-to-peer communication based on packet transport network (PTN) equipment is investigated. Also, the network topology for peer-to-peer communication based on high-availability seamless redundancy (HSR) ring network technology is studied. At last, the comparisons between various network schemes are presented, which provides a beneficial guidance for the construction of regional protection and control system.

Abstract:With the problems of low speed of changing load, high fluctuation of main control parameters and the over-heat of main steam temperature of the 1000 MW ultra supercritical unit in Chaozhou power plant, this paper proposed an advanced control method of automatic generation control (AGC), which can be applied in the field with the INFIT real-time optimization system. The performance indicated that the advanced control technology can significantly improve load regulation ability, the operation stability of the unit and the average steam temperature of superheat and reheat, thus global safety and economy of the unit were improved.

Abstract:This paper puts forward a comprehensive control method of UHV receiving end power grid based on user intelligent interaction. The load flexible control cloud platform, together with the existing dispatching operation and marketing system, realizes load regulation by intelligent electrical outlet with the function of micro-control and infrared adjustment. When high power deficiency happens caused by UHV failure or emergency shutdown, the load control of flexible cloud platform can play an important role on controlling virtual power plant flexibly and fine. The large-scale virtual power plants response to form clusters aggregation effect, contributing large power to support grid power supply and demand balance, to ensure the safe and stable operation of power grid.

Abstract:With the development of Jiangsu UHV power grid, reliable outer power is important for regional power supply. Supports from provincial power grids are needed at the receiving end of UHVDC which brings large amount power into the grids. The loss of power caused by bipolar blocking needs to be allocated and the power flow among the power grid has to be redistributed. Tanking a historical UHVDC blocking event in Jiangsu power grid as an example, responding characteristic of local power sources and supporting characteristic of outer power sources are analyzed for the case of outside power loss. The research provides some references to the power flow control for outside power loss.

Abstract:The reactive power compensation devices located at high voltage DC inverter is mainly used to provide reactive power to support active power transmission. The dynamic characteristics of reactive power devices have significant influence on voltage stability and DC operating characteristics. Based on control strategy, this paper analyzes the influence of synchronous condenser on DC inverter operating characteristic during AC voltage fluctuations. The characteristics of reactive power output and the response characteristics of the inverter station are revealed and verified by simulation results. The research provides theoretical foundations to the integration of large capacity synchronous condenser to multi-infeed DC power grid.

Abstract:Under the action of promoting air pollution control action in the country, the East China UHV backbone network has formed, which increases the ability to accept external power. This article mainly analyzes the key influence factors of the scale of power consumptive area. Supply-demand balance and safe operation are also considered. According to the electric power load increase trend, local power sources constructing plan and power grid developing plan, the scale of outer power, possible changes, power transfer channel capacity and some limiting factors are considered. After the calculations of internal power balance and power exchange, it is found that the ability to accept outer power of Jiangsu power grid by 2020 is great enough.

Abstract:When power system substation protection's secondary DC power is lossed, and soon afterwards if a fault occures in the power loss area, the protect devices can not isolate the fault quickly. This paper popses a power loss area distance protection system t solve the problem. The architecture of the protection system and its construction mode for substation are presneted. The control system architecture and its construction mode for the area protection in substations are introduced in detail. Substation's secondary DC power loss is judged by the idependent power sources of process layer communication network and protection. The general scheme of power loss area distance protection based on substation's secondary DC power loss is propsoed, which can quickly isolate the fault in the DC power loss area. The RTDS simulation results show the presented method can correctly judge substation's secondary DC power loss state, quickly isolate the fault in the power loss area, and ultimately improves the stability of the system.

Abstract:This paper discusses the security protection principle of electric power monitoring system through analyzing the requirements of security protection and the existing security threats in electric power monitoring system. According to the structure of LTE system and its deployment pattern in electric power area, the protection methods are analyzed by using safety risk analysis. At the end, from the point of views of business side, LTE messing and boundary, a fully protective solution to LTE wireless system in electrical area is proposed. This solution provides ideas for establishing security protection system of special wireless network in electric power area, and it is certainly valuable to developing security strategy for LTE network in the future.

Abstract:The planning and constructing mode, as electric power enterprises are investors, for city power pipeline and their advantage and disadvantage are studied. The traditional decision method is improved, in which the optimization is set as maximize economic benefit. The improved method can satisfy the constraint. In order to improve the decision level, a life cycle based decision and computational method for pipeline planning to search the best solution is proposed.

Abstract:This paper studies the on-line monitoring issues for water treeing of electric cable cross linking system by using DC component method. The standard cross-linking system is analyzed and its equivalent circuit is established. The factors causing faint DC current component are studied quantificationally. Current sampling and low pass filter modules are designed and the weak DC current component can be sampled and filtered. Field testing results show that the current sampling and low pass filter modules are correct.

Abstract:With the distributed generation increasingly integrating to the grid, the traditional single feeder radial distribution network becomes unsuitable. Based on the communication and power electronic technology, the feasibility of distribution network closed-loop operation is analyzed. Based on the Z-bus method, the power flow calculation method for the distribution network with distributed generation and rings is proposed. The economy of distribution network closed-loop operation is analyzed. For the hand in hand double feeder distribution network, the voltage phase angle difference has great influence on the loss of closed-loop operated distribution network. When the difference is not too big, closed-loop operation is economic and security. Compared with the reconstruction of distribution network, the closed-loop operation decreases network loss and improves voltage quality more obvious.

Abstract:The problem of the interoperability between IEC 61970 and IEC 61850 in smart grid is studied. Firstly, the data structure model of the two standards is analyzed. Secondly, the possibility of the interoperability between the two data models is discussed. Finally, taking main wiring structure of double busbar with bus coupler circuit breaker as an example, the models of IEC 61970 CIM and IEC 61850 are established respectively. The data exchange and model mapping between the two standards are described in detail. The result shows that this method to exchange data between the two standards is feasible.

Abstract:The economy of Lianyungang is developing rapidly; also the electricity consumption is in rapid growth. By analyzing the growth trend of GDP and power consumption and analoging the power consumption to the cities with faster economic development speeds, the cities with similar development law are found. According to the economic policy of Lianyungang, the load values of the next few years are predicted by using intelligent algorithm. The actual value and prediction values of corresponding times are compared, which indicates those two values are almost the same. The perdition method is helpful to Lianyungang's 13th plan of five-year power grid development.

Abstract:In the view of current repairing process in transformer substation, this paper introduces a kind of relay protection multifunctional testing platform to solve the problem of supplying reliability decrease, which is caused by the difficulties such as carrying tester, supplying power and wrong operation etc. The testing platform is made up of crawler base module, inverter circuit module, voltage electrical measuring module, regional alarm isolation module etc., which can help testing personnel to climb stairs and cross obstacle, and supply power to testing equipment from self-contained power source and define insulation zone to avoid accidently coming to the zone etc. The results of the field testing in Nanjing 220 kV substation show the use of this platform could enhance the security of the substation maintenance, increase the efficiency of the substation operation maintenance, and improve power supply reliability.

Abstract:More and more UHV transmission line pass through forests. A method of forest fire monitoring based on infrared detector is proposed to reduce the influence of forest fire to the stabilization of UHV transmission. The signal of forest fire is detected by infrared detector and sampled by DSP based equipment. The location of forest fire is displayed by a background program. A virtual forest fire is detected. It is proved that the equipment can monitor forest fire in a certain area and the method is practicable.

Abstract:The performance of the current transformer used in protection is of great significance to the action of relay protection and the operation safety of power systems. In order to evaluate the performance of the current transformer used in protection, it is necessary to implement excitation features test. The commonly used excitation features testing methods (such as power frequency method, variable frequency method and direct current method), as well as their advantages and disadvantages are introduced. It is pointed out that the variable frequency method should be adopted for the excitation features testing of 1000 kV current transformer. Moreover, the excitation features testing schemes for the 1000 kV current transformer used in Gas Insulated Switchgear (GIS) are introduced. Finally, according to the field testing data of the 1000 kV current transformer, the performances of the tested current transformers are analyzed.

Abstract:This paper introduces the status and limits of traditional urban distribution network, analyzes the morphological characteristics of distribution network of new-type towns, focuses on the influence factors and technical measures of operating evaluation for distribution network, and further studies the quantitative effects of network topology, equipment level, automation level, distribution generation connections and reactive power compensation on operating evaluation indexes. Taking "National Model Town Planning" as the guidance, the power supply modes of distribution network of new-type towns are classified into three types: namely the green, the intelligent and the humane. Taking green energy as an example, the necessities of grid construction, as well as the construction targets, the construction content and the mode configuration of supply power modes are analyzed. At last, the key contents of construction, index requirements, and technical measures of the six supply power modes are proposed.

Abstract:Taking the Dong San III 500 kV line as an example, this paper introduces the application of wire insulation wrapping technology in preventing wind drift. The insulation wrapping wire technology is selected from two aspects: limiting wire wind drift and improving insulation strength of air gap. The feasibility of the scheme is authenticated and the thickness of the insulation material is determined by simulation and test. The factory prefabricating and field installations guarantee the quality and shorten the operation time.

Abstract:Effective supervision is required in GIS manufacturing process to ensure its quality in substation engineering construction. This paper introduces the key factory test method and problems of the test process for 1000 kV GIS from the perspective of supervision manufacture. The paper provides a reference for the supervisor factory test of other voltage level GIS.

Abstract:Condition monitoring and fault diagnosis of rotor windings of double fed induction generator (DFIG) can detect the fault timely and reduce operation and maintenance costs effectively. First, a double fed induction generator's rotor fault model is established in PSCAD software based on its mathematical model, and then the fault characteristic frequency of the grid-side current of back-to back converter is detected through simulation analysis. In addition, the experimental platform of double fed induction generator is built in laboratory, and the recorded data is analyzed by using FFT under different operational conditions and different fault levels. Thus the fault characteristic frequency of the grid-side current of back-to-back converter is validated. Also when rotor fault severity is intensified, the fault characteristic frequency amplitude increases.

Abstract:The anti-mislock function of 110 kV SF₆ based GIS is comprised of one electric blocking coupled with an interval logic blocking. The double-blocking enhanced the ability of preventing anti-mislock. The breaking failure of disconnecting switch caused by the abnormal of double-blocking anti-mislock device is analyzed. Based on the analysis, from the point of view of operation and maintenance, some improving plans and measures to prevent the abnormal of double-blocking anti-mislock devices are proposed.

Abstract:This paper presented the retrofitting of external steam cooler in a 1000 MW ultra supercritical unit. The operating parameters of high-pressure heater system, before and after operating the external steam cooler, were analyzed. The result indicated that the external steam cooler can cause the bled steam at different level exclusion, which can increase the thermal cycle efficiency of the whole system and the power margin of the unit, and reduce reversible energy loss caused by heat transfer temperature difference of No.3 high-pressure heater, thus had economic benefits obviously.

Abstract:Based on the characteristics and external conditions of a 2×600 MW unit in a coal-fired thermal power plant, an effort were devoted to simplify the system, reduce project cost and reduce operation maintenance costs, under the premise of the reliable operation of the system. Two different slagging schemes, slag conveyor and air-cooled steel slag machine, were analyzed and compared in the field of the technical, investment, operating costs and so on. Finally, slag conveyor cleaner program was used as the lagging scheme of this project.

Abstract:This paper described the requirements, the correct method and matters need attention of the LZC139-13.2/1.4/555/550 steam turbine casing collision test, which was relied on the project of one 2 × 400 MW grade gas turbine cogeneration of Guoxin Xielian power plant. Then the problems raised from the test were analyzed and summarized. The aim of this project was to provide guidance for carrying out the collision test correctly in the same type of units.

Abstract:With the inaccurate measurement of sampling tube of negative pressure measuring device caused by plugging ash, this paper introduced the sampling tube which can continuous purge and prevent dust. Fluid mechanics basic theory was applied to describe the effect of compensation purge on the design of sampling tube. Field test data was used to determine the flow rate and pressure of the purge. In addition, attentions should be paid in the field were described. The negative pressure sampling device could prevent ash fouling, which can be used as the negative pressure measuring device of furnace in power plant.

Abstract:Due to the support-hanger for temporary pressure test was not removed, the thermal displacement of main steam pipes in 300 MW coal-fired units was blocked, and the secondary stress of pipes exceed allowable stress of materials. According to the national standards, integrated stress analysis software of CAESAR Ⅱ was applied to analysis the static load of pipes, then the support-hangers were redesigned appropriately. The peak secondary stress of the piping was declined to 53.2% of the allowable stress, and the safety margin of the pipe was improved.