The die
casting part production flow chart
Injection
speed of die cast process
Pouring
liquid metal tie up chamber volume percent
Injection
speed(cm/s)
≤30
30-60
>60
30-40
20-30
10-20
High
speed computing formula
V
-------------Cavity volume (CM3);
N ------------ Cavity No;
D ------------ Die-casting drift (CM);
T ------------- Proper filling time.
The production of aluminum and Zinc Alloy Die Casting parts.
A380 Aluminum Die Casting, Aluminum Die Cast Part, Die Casting Parts, Zinc Die Casting NINGBO BEILUN LEMA MACHINERY TECHNOLOGY CO.,LTD , http://www.china-lema.com
At present, there are great differences in hardware and software platforms and system implementation technologies for power dispatch automation, which brings difficulties to data sharing and software interconnection between applications. The solution is usually: 1 collect data of each application system across departments; 2 develop point-to-point interfaces as required. The disadvantages of the above methods are that the correlation between subsystems within the system is complex and lacks a standard database access interface, resulting in a large amount of redundant data, and thus resulting in inconsistency of the data. At the same time, the newly built system will temporarily avoid becoming "Isolated islands of automation systems", but will not create a shared, efficient distributed data platform that the system needs. In recent years, the research and development of power dispatching automation systems based on CORBA middleware technology, public information model (CIM) and other integrated designs have attracted widespread attention, especially the continuous improvement of the IEC61970 standard, providing the development of integrated systems. The more powerful the technical support. In this integrated system, SCADA/EMS, power market technical support system, dispatcher training simulation system (DTS), report generation system, dispatch MIS, operation ticket management system, etc. are integrated based on a unified middleware platform. However, on the one hand, the research and development of integrated systems have yet to be perfected. On the other hand, there is a big difference between the existing application modules of integrated information systems and integrated technology standards based on middleware modules, which are difficult to integrate. Whether for funding, technical considerations or application continuity considerations, the development and application of integrated systems is a gradual process. In order to give full play to the role of existing application modules, and to promote the improvement of existing systems or the development of new application modules in the direction of integration, this paper proposes an approach based on the existing applications, potential applications, and correlation analysis of dispatch automation systems. An Integrated Design Model of Power Dispatching Automation System Based on Scheduling Public Data Warehouse. In the current five-level scheduling system, each level of scheduling has its own characteristics. The analysis of this paper is based on the provincial regulation system.
1 The power grid dispatch monitoring system is to save the main station end, and the main part used for power grid monitoring is SCADA/EMS. The provincial SCADA is responsible for data acquisition, data processing, event sequence recording, accident recall and retrieval, history data management, and various reporting systems for provincial grid 220kV and above substations, some 110kV substations, and provincial power plants, and is responsible for network adjustment. Communication systems for station systems, ground adjustment systems, and other related systems.
Provincial EMS includes Network Modeling and Topology Analysis (NMB), State Estimation (SE), Dispatch Force Flow (DPF), Static Security Analysis (SA), Short Term Load Forecasting (SLF), Network Loss Analysis (NLS), and Automatic Generation Control (AGC), Automatic Voltage Control (AVC), etc. Among them, NMB, SE, DPF, SA, SLF, NLS and other modules are mainly based on the real-time or historical data of the power grid to calculate and perform various aspects of power grid analysis, while AVC and AGC perform grid voltage regulation and frequency modulation according to the real-time operating status of the power grid. And economic dispatch.
Provincial SCADA/EMS requires a variety of data from power plants, substations and regional dispatch. On the station side of the plant, the grid monitoring system mainly includes the substation integrated automation system and the computer monitoring system of the water (fire) power plant. The upstream information involved includes voltage, current, active power, reactive power, and other real-time telemetry and circuit breakers, switches, etc. the amount. The power angle of the power grid is an important parameter for the safe and stable operation of the power system. With the development of GPS clock synchronization technology, the conditions for real-time measurement of the power angle of power grids have become more mature and will become the measurement content of SCADA systems. The downlink information includes control information such as AVC and AGC.
At the primary site, the SCADA/PAS is an important part of the grid monitoring system. At present, the content of the communication between the local government and the provincial government includes the transfer of real-time data of some substations and the total power plus gateway information of each region. With the implementation of the provincial-level dispatcher's joint training system, the real-time information of the 110kV substation and some substations below 110kV will also be important information transferred to the province.
The information flow of the power dispatch monitoring part is shown in Figure 1. 
At present, the main function of power system relay protection and fault information management system is to use computer technology and data communication technology to collect information on the protection of the computer and fault recorders at the station end of the plant, and to inquire about the state of protection and historical events in the substation under jurisdiction. Record the data and operation information of microcomputer protection fixed value, analyze the various conditions of the line fault according to the data of the wave recording device, including the fault distance, fault type, current and voltage waveforms and harmonics at the time of fault. The protection setting is not yet put into practical use, but there should be no technical problem. Some values ​​of protection in the power grid are closely related to the way the grid operates. With the development of power grids and the needs of the electricity market, FACTS (Controlled Series Capacitance Compensation) will gradually be applied, which will lead to flexible changes in grid structure, grid operation modes and fault component parameters after faults. Electrical protection puts forward higher requirements and puts forward self-adaptive requirements for relay protection setting. Therefore, using the EMS data to analyze the changes of the power grid in a timely manner and calculate the protection value online will be an important application of the EMS data and an important function of the power system relay protection and fault management system.
Due to the increase of load level, the expansion of power grid scale and the improvement of the reliability of power supply, preventing the destruction of transient stability is one of the most important tasks in the current power system. In the course of the operation of the electricity market, the system operation mode has become more and more complex and rapidly changing, requiring more rapid, accurate, and effective stability control measures. These new changes and requirements make traditional on-site stability control devices based on "offline computing and online matching" less and less suitable for the needs of power system development. According to the real-time information obtained from the EMS, online generation of optimal policy tables and downlinking to each regional control system has become another very important application of EMS data.
Relay protection and intelligent stability of the information process shown in Figure 2. 
3 Power Market Technical Support System Since the late 1980s, the United Kingdom has begun the practice of the electric power market. From the mid-1990s onwards, many units such as Tsinghua University, NARI Group Corporation, China Electric Power Research Institute, and Dongfang Electronic Information Industry Co., Ltd. started research work on the power market technology support system. The State Power Corporation and the relevant provincial bureau In the six power grids in Shandong, Shanghai, Zhejiang, Liaoning, Jilin, and Heilongjiang, pilot sites for “spreading the plant and network and bidding for access to the grid†were conducted. In 2000, the power-supply-side power market technical support systems of six units were put into operation. At the same time, power companies in Henan, Hunan, and other provinces also carried out related work. Looking at the above-mentioned power market technical support system, although its implementation is different, the system functions are similar, including the following aspects: Electric energy measurement and billing system, energy management system, power generation quotation system, transaction management system, contract Management system, settlement system, instant messaging system and market analysis and forecasting system. In addition, distribution companies and large-user data declaration systems are also indispensable when considering distribution-side power markets. The State Power Corporation has given the information flow of the technical support system for the power market in the "Functional Requirements of the Power Market Technical Support System." The power market technical support system realizes the monitoring, regulation and control functions of the power system through SCADA/EMS.
4 Water Leveling Automation System The water leveling automation system performs monitoring, forecasting, scheduling and management related to the operation of the reservoir. It is based on hydrologic, meteorological, and reservoir operation history and real-time information of hydropower basins or other related systems, on-line hydrological forecasting, optimized dispatching, and integrated reservoir management. Combined with power grid operation and unit real-time information, it provides flood control based on relevant mathematical models. The integrated dispatching and decision-making scheme including power generation can automatically control the opening and closing of reservoir gates, support the economic dispatching of hydropower plants and power grids, and the joint dispatching of hydrothermal power, and on this basis form the hydropower plant power market quotation system.
5 Dispatcher Training Simulation System Dispatcher Training Simulation System (DTS) uses computer technology to create a mathematical model of the actual power system, reproduces various scheduling operations and system conditions after the failure, and sends this information to the power system control center. The model provides a realistic training environment for the dispatcher to achieve the goal of not only affecting the operation of the actual power system but also bringing the dispatcher to an immersive practice drill. At present, dispatcher training simulation systems in power systems around the world are increasingly becoming powerful tools for improving the level of power grid operations and handling accidents.
With the increasing popularity of DTS and the rapid development of computer technology, the connotation and use of DTS are expanding. At present, DTS is not only used for the training of dispatchers, to improve the level of dispatchers, but also to be used as support and decision makers for power grid operations. Research tools, such as operating mode personnel to develop a reasonable mode of operation through DTS, study the special operation mode of the power grid, conduct research and analysis of the planned power grid, relay protection personnel through DTS for reasonable relay protection setting configuration and anti-accident measures Research and use telematics for provincial training and anti-accident exercises.
The raw data produced by the training system lesson plans comes from the real-time or historical data of the EMS. In order to adjust the joint training in the province, real-time data of 110kV and below are required to be transferred from the ground, and remote channels are required to exchange information between DTS and DTS.
6 Lightning Positioning System The lightning positioning system filters the collected signals of the lightning collection device on the site and uploads the lightning current, lightning polarity, the number of lightning strikes, and the time of the lightning strike to the dispatch center to assist in the fault analysis and fault location of the dispatch. . Other applications with scheduling automation systems have relative data independence.
7 scheduling MIS
Scheduling MIS has yet to have a unified statement, but one thing we should be sure is that serving real-time dispatch of power systems should be an important task for scheduling MIS. Therefore, it should be based on the aforementioned applications of the dispatch automation system and make full use of the information generated by various applications to provide data information to the power company's ERP, MIS and GIS systems.
8 Integrated scheduling and scheduling of power dispatching data warehouse and power dispatching automation system The application systems at the main station end include SCADA/EMS, relay protection management system, intelligent stability monitoring master station system, water adjustment automation system, dispatcher training simulation system, and power Market technical support system, dispatch MIS, lightning positioning system, etc. In addition to the lightning location system, the rest of the sections share the operating data of the grid. The data association between applications is shown in Figure 3. Based on this connection, if we design a scheduling data warehouse, we can get the data flow shown in Figure 4, which is the integrated design flow of the power dispatch automation system. 
The scheduling data warehouse in Figure 4 has the following characteristics: 1 The scheduling data warehouse has simple SCADA functions, state estimation functions, and real-time and historical data storage functions. On the one hand, it separates some functions of the original SCADA/EMS and DTS, on the other hand, Become the link between the main applications of the dispatching automation system; 2 The public data of the main applications of the storage dispatch automation system, including the real-time data, historical data, grid equipment data and other public data of the power grid operation; 3 provides convenience for external applications, The standard access interface; 4 access speed should meet the requirements of various applications in terms of time.
The integrated system based on data warehouse has the following advantages: 1 The data warehouse stores the grid operating parameters, equipment parameters and other public data in a centralized manner, reducing the redundancy of the data; 2 The application programs of the dispatching automation system mainly deal with their respective application functions and private ownership. The data and system design are more in line with the object-oriented design philosophy. 8 Each application system is relatively independent. It is relatively relevant to other applications both in the construction of new application subsystems and in the updating process of old application subsystems. Small, can better meet the needs of the gradual update and reconstruction of the dispatching automation system; 4 scheduling automation system only access to the base station plant data through the scheduling data warehouse, through scheduling MIS delivery scheduling information, so that the population, exports simplified, system data The process is simple and clear, which facilitates the security of the dispatch automation system.
9 Conclusion In this paper, the provincial regulation system is taken as an example to comprehensively analyze the existing applications and potential applications of the power dispatch automation system, and an integrated design model of the power dispatch automation system based on the dispatch data warehouse is proposed. The integrated design of the dispatching integrated automation system has an extremely important significance for the integration of the existing dispatching automation system and the construction of the power dispatching data network, the power dispatching public data warehouse, and the power dispatching MIS.
Integrated Power Dispatching Automation System Based on Data Warehouse
Introduction In the past 10 years, with the rapid development of technologies such as computers, communications, data networks, and databases, as well as the need for safe operation and commercialized operation of the power market, a new generation of power grid dispatch automation system is gradually being formed. The system needs to consider the power market environment. Requirements for safe operation and commercialized operation, unified SCADA/EMS/DTS, relay protection, safety automatic device and intelligent stability management system, power market technical support system, water adjustment automation system, dispatch MIS and lightning positioning system, etc. Design to achieve a high degree of sharing of data and resources. 2 Relay Protection and Intelligent Stability Measures In the power system, relay protection plays an important role in disconnecting faulty components (generators, transformers, buses, lines, etc.). Intelligent stability measures need to remove the imbalance of the system in time when the system fails. Output or unbalanced load, and strive for stable operation of the system. In recent years, at the main station of the dispatching network, the power system relay protection and fault information management system and the intelligent stability monitoring master station system have gradually attracted attention.