Shanghai's Western District Power Supply Board (WDPSB) in China supplies an area of 50.24 km² (19.4 m²). By 1999, the population exceeded 1.5 million, with 420,000 consumers demanding 879 MW of electricity from the system.

Due to rapid expansion of the distribution network, the mimic control diagram in the load dispatch control room was too small to display the complete network diagram. This schematic diagram displayed the poles erected on each side of the road to support medium- and low-voltage lines, but it was too inconvenient for control room staff to use.

Thus, in the late 1990s, the WDPSB decided to develop a computer-aided information management system. Following detailed investigation of the problems, combined with consideration of the evolving computer technology, WDPSB recognized the need for a system that provided spatial information. As a result, it decided to integrate an automated mapping (AM), facilities management (FM) and geographic information system (GIS) into an information management system (IMS) for WDPSB.

Information Management System

Fundamentally, construction of an IMS is a system engineering exercise that combines system analysis and system synthesis from the outset of the initiative.

WDPSB had no mature precedent to follow in applying the AM/FM/GIS. However, the team did have prior knowledge of the degree of integration of the system and had seen a limited scope demonstration of the IMS system and application software, including:

• UNIX operating system

• Microprocessor platform software MapObiects

• GIS workstation platform software ARC/INFO

• GIS intranet query platform development software Internet Map server.

• DBMS software ORACLE

• FM development tool Delphi integrates with SCADA, with a 100 Base-T network system.

With WDPSB tackling integration of such a tremendous system, difficulties were expected during development. The AM, FM and GIS software are produced by different software vendors, while the database and graphics information is established on a dual-system diskette array. Most of the GIS information is taken from the FM management database. Because information query standards for AM, FM and GIS software are not completely similar, it was difficult to allot the resources of microprocessor and network services. WDPSB harmonized the AM, FM and GIS software into a single system to provide a strong graphics function and coordinate between multimedia interfaces.

In the background, high-performance ARC/INFO and ORACLE tools are used to manage the database and graphics library. The whole system is consistent with a client/server plus browser/server structure that enables WDPSB to integrate the products from different manufacturers, enabling the AM/FM/GIS to run throughout the whole system. Operators may access any layer as required without paying attention to other GIS applications; hence, the present system can achieve high utilization. The method of systems engineering developed enables this system to achieve a high degree of integration.

At the initial stage of using an IMS incorporating AM/FM/GIS techniques, detailed specifications and standards should be formulated, and unified standards should be established in as large a range as possible, to share the AM/FM/GIS information and network interconnections.

Design of the System Topology

The design of the system architecture was in accordance with the overall requirements of the IMS required by WDPSB and international technical development of AM/FM/GIS platform software. The IMS has synthesized advantages of the client/server structure and brower/server structure and adopted mixed architecture of C/S + B/S, so that it can flexibly bring the advantages and features of both structures into full play when it is used in different layers. The system architecture is shown schematically in the Fig. 1. Logical structure diagram of system software is shown in Fig. 2.

Design of System Network Structure

The WDPSB system network included the following hardware and network technology.

• Two DEC Alpha Server 2100s adopted for middle-range servers, constituting dual-system back-up mode, with Digital Tru64 UNIX operating system and Digital TruCluster cluster software installed. Two servers share one RA310 disk array.

• DEC workstation is adopted for five workstations, installing DEC UNIX operating system.

• Adopting servers of PC level as Web servers, OA servers and application servers, PII300 or PII350 as CPU, RAM with 128M.

• 100 BASE-T high-speed Ethernet has been adopted as trunk network; optical fiber for connection between different layers of floors; CAT5 UTP wires internal to the building.

• 3Com Link Switch 3300 is used as exchange device for trunk network.

• LinkSwitch 1100, LinkSwitch 1000 and LinkSwitch 3000 of 3COM Corp. are adopted for branch network.

• Remote communication support is provided through 3Com Access-Builder 2208. Thus, the remote users (mainly Jiangnin central station and Shuicheng central station) can be interconnected with PSTN; interconnection with superior units is realized via a unified communications network of municipal dispatching center for remote control.

• Interconnection with SCADA system is carried out via gateway.

Summary

The information management system of the WDPSB is a key scientific and technical project of Shanghai Urban Power Supply Corp. It is also a key project of Shanghai Municipal Science Commission. Improved results and social appreciation has been achieved since it was put into service.

Zhong Xiaojun is a well-known expert in GIS-related area. She was the principal engineer responsible for the design, implementation and management of the first distribution AM/FM/GIS in China. She was appointed the director of a DMS project, resulting in widespread acceptance of GIS and application in Shanghai distribution networks.
zhongxj@smepc.com

Zhou Yongxing, the vice president of the East China Grid Co. Ltd., has 23 years experience in the power distribution sector. During his career in the Shanghai Urban Power Supply Bureau (SUPSB), he has been responsible for the introduction of world-leading technologies to power utilities, such as GIS, management information system and office automation. In 1999, Yongxing was awarded the Ph.D. in science of management at Shanghai Jiaotong University and is now a senior member of the Chinese Society for Electrical Engineering.

Zhang Fan has 11 years experience in the electricity industry. From 1994 to 2004, he lead several important projects, including facility management system, GIS, mobile commerce, PQ management system, street-light monitoring system, PLC-based remote metering system and power station automation system. Currently, Fan is the general engineer of Shanghai Jiulong Electric Group Co. in charge of research and development.

System Application Model

Classification of Models	Description of Model Function
Common model	Multilayer display; zoom in/zoom out; equipment enquiry; equipment statistics; graphic printing; system management
Dispatching model	Simulation of line switch operation and for analysis of service interruption area; optimized scheme of service interruption computer-aided decision making; computer-aided decision making for trouble call management (TCM); intellectualized tracing after switching operations and safety control; tracing analysis of multilevel power sources; analysis of supply area of pole-mounted transformers; computer-aided decision making of line load transfer; service interruption management (planed and non-planned); power station information management; analysis of impedances; calculation and analysis of power-supply reliability.
Feeder operation model	Power supply area of feeder; tracing analysis of multilevel power-supply sources; computer-aided decision making of TCM; alleyway mains editing maintenance.
Models of enquiry for electricity supply	Analysis of load curves; analysis of power supply area of pole-mounted transformers; electricity supply tracing analysis of multilevel power-supply sources; defining reserved poles' information and enquiry; power station management; graphic digitization.
Dynamic management model for equipment in operation	Construction management; lines management; substation management; distribution management, pole-mounted transformers management; plan management; insulation management; relay protection management.
Intranet enquiry model	Enquiry of key index; enquiry of distribution management; real-time enquiry of network; electronic forum; information movement.
Data maintenance model	HV line editing; MV line editing; LV line editing; power station simulation diagram editing; digitizing and editing of primary line diagram of power station; graphic digitizing and editing of consumers supplies by dedicated feeders; digitizing and editing of system diagram; digitizing and editing of relay panel diagram; editing of distribution diagram of substation sites; editing for newly added symbols.

Software Applications

Development Tools

• AML. In the development of ARC/INFO software, fourth-generation macro-language AML is adopted as a development language for graphic application software

• Delphi. In the development of MapObjects software, Delphi 4.0 is adopted as a tool for developing FM and Internet background application-server software.

• Jbuilder. In the development of Java Applet through Jbuilder, the user is provided with a distribution network diagram based on the Internet, and information enquiry through Java Applet is developed with Jbuilder.

• Visual InterDev. Use visual InterDev to compile a corresponding ASP scenario. Use Active Data Object for information enquiry and analysis on various data sources of ORACLE. Use FoxPro to accelerate the operation speed by compiling a great amount of storing processes in the ORACLE background database with PL/SQL.

Application-server Software

• Active Server. Application-server software of intermediate layer for Intranet comprehensive enquiry system.

• Internet Map Server. Application-server software of the intermediate layer for accessing space graphic data in power distribution management intranet enquiry system.

Web-server Software

• Internet Information Server is used as server for intranet.
• Lotus Domino Go is used as Web server for intranet's part of OA.

Other Software

• Hummingbird Exceed 6.1. X-terminal software for operating UNIX application on Win95/NT platform.

• Hummingbird NFS Maestro Solo. NFS user terminal software for accessing file resources on UNIX on Win95/NT platform.

• ArcStorm is mainly used for coordination changes and revisions of space data and corresponding external database, realizing C/S structure-based routine management of objective level through using or supplying with database record locking, recovery mechanism, SCHEMA integration and management of historical information.