Electricidade de Portugal, S.A. (EDP), like many electric utilities around the world, faces the challenge to reduce life-cycle cost, increase customer value and improve flexibility in operation and services. To achieve this goal, EDP has embarked on a computer system integration that spans the various forms of data and services dispersed in many business processes.

Computer-based applications have been growing in complexity and interdependence over the last decade. Supervisory control and data acquisition (SCADA) and other technical computing applications must interface with the corporation's information and business activities. The challenge is to ensure that the selected system survives the introduction, replacement or removal of any integrated application, without repeating the “ten year buy everything” cycle of the past.

Global Restructuring of the Electricity Business

Adopting the same business strategy as other utility companies, EDP is strongly motivated to create the multi-utility company concept in Portugal, an approach that will benefit from EDP's strong technical background.

With the market liberalization and the development of the telecommunications business, EDP decided to use its technical skills and engineering capabilities to develop a second core business that could compensate for any loss of the electricity market share or to increase profits. Together with this strategy, EDP explored other business opportunities with process similarities, namely, gas and water utilities. As a result, EDP has adopted a policy of acquisitions in these areas to take advantage of scale economies.

The EDP Distribution Group found that a new market approach that included a new corporate identity required changes in the utility's attitude and organizational philosophy. The restructuring process started in January 2000 when EDP merged four existing regional distribution companies into a single national distribution company, EDP Distribuição, S.A.

EDP considered its philosophy for Network Control Management Centers essential to the success of this new market approach. The company decided to reduce the number and improve the efficiency of the control centers spread over the Portuguese territory. This program started in Lisbon (Lisboa), where EDP has a control center for three network areas. EDP is now working to achieve a final goal of two high-voltage (HV) control centers located in Oporto (Porto) and Lisbon, and four medium-voltage (MV) control centers in Oporto, Coimbra, Lisbon and Setúbal. This demanding program is difficult to achieve, so EDP examined available technologies for hardware and software systems with the capability to satisfy these objectives.

EDP intends to export this technology outside Portugal to those companies where EDP already has a presence.

Modern Control Center Configuration

Distribution automation (DA) is a key factor to providing the means to integrate networks, databases, applications and share data in the various utility business divisions. EDP identified systems that would provide quick returns on investment and improve customer service and satisfaction. This was the scope of the “EDP SIRED IT Project” (Integrated System for Technical Management of Distribution Networks), covering different areas including planning, trouble call, works management, network as-built data, operations and supervisory control.

EDP awarded the DA contract to EFACEC Sistemas de Electrónica for the development, supply, installation and commissioning of the supervisory control and data acquisition/distribution management system (SCADA/DMS).

For the data relating to the electrical network characteristics, Smallworld's Geographical Information System (GIS/SW) manages all cartographic and electrical network as-built data. This is the single point for data entry providing network configuration to other systems and is the most reliable information repository in EDP allowing several departments to manage their work with ready-to-use information and ready-to-use testing and simulation.

The Distribution Control Center (DCC) that controls the HV/MV network employs a SCADA/DMS system sharing data with the GIS and trouble call systems (Genesys Project). EDP prepared the specification for this system with the assistance of KEMA Consulting, following which a project team was formed with EDP staff working in partnership with EFACEC the company that supplied the existing conventional SCADA system. With this business contract, EDP seamlessly integrated the existing SCADA system with the new SCADA/DMS system. This will be the main force of EDP's ability to control the network in an integrated and centralized way and to have different systems sharing information. Single-point data entry offers several possible advantages: data consistency guarantee; network operation and maintenance optimization; investment cost reduction and optimization; quality of service improvement provided to the client; and energy supply and demand management optimization.

EDP implemented sound software architectural principles, providing the foundation for an integrated environment enabling data sharing. The project follows modern trends in integrated component-based software architecture, reducing system upgrade complexity, cutting risks and reducing costs. EDP is committed to pursuing modern trends while keeping traditional performance and scalability of SCADA/EMS/DMS systems.

Systems Architecture, Protocols, Communications

These systems are highly distributed and, therefore, communication is an important issue. How well can these systems communicate with each other? How does it manage the communication network loading? How does it guarantee data integrity across systems? How does the system behave in a troubled communication network? Tackling these issues requires above all the definition of a software architecture giving support to a framework on top of which applications and systems are put together.

The system is built on top of a component-based distributed computing environment — Collaborating Component Architecture (CCA). Components may be seen as functional units tied together to provide full functionality to the end user. A Publish-Subscribe communications model provides the foundation for component cooperation, functional independence and loose coupling of components. Components are linked together with a software bus with an event model. The components behave in a fashion such that the user is unaware of hardware, network environment or internal bus layers.

Convergence to a Common Object Request Broker Architecture (CORBA) is a trend, and the best strategy is to build the CCA so it can take full advantage of CORBA-compliant proven commercial products. The role of the CCBus is to provide a layer of code that isolates components from the direct usage of CORBA, as well as to provide a common and consistent framework to the development and run-time environment of a component. CCA is conceived as an appropriate way of using CORBA as well as DBMS-proven client-server distributed environments to meet requirements, reduce risk and reduce the costs of constructing, maintaining, scaling or extending the system.

EDP's DA Study and Experience

The new DCC project adopted a phased approach with evolving stages of prototyping and industrial pilots, allowing the utility to mitigate risk and track work progress. EDP anticipates the 2002 deployment of an industrial product with the following features:

  • Hardware architecture of the SCADA/DMS based on three duplicate servers (SCADA functions, Historical Information Management and DMS functions).

  • Integration with the GIS/SW system. The GIS is the single point for data capture and is responsible for managing network configuration with versioning capability through hierarchical organized alternatives.

  • Managing the operational state of the network with the help of a tagging subsystem implementing an electronic wallboard function. An external DBMS outside of Smallworld manages the operational data model.

  • Realworld and studies synchronized with Smallworld version management.

  • Network coloring and tracing enhancements; switching orders and safety checks; power application support, such as a power flow, short-circuit calculations, load allocation and load forecast.

  • A SCADA gateway component linking the built-in kernel SCADA modules.

Concerning the Smallworld GIS Interface, the figure on page 52 depicts a system configuration overview with some main components distributed over two nodes: a server and a workstation.

A future stage for this architecture will include its integration with the new outage management system (Power On) that will replace the existing EDP trouble call system based on an IBM mainframe. This integration will bring together the call center, the customer information system (CIS), the crew management and the enterprise resource planning system (ERP), which gives the control center a seamless, end-to-end solution for the network operation on the HV, MV and LV network levels. It will allow the creation of outages based on information received from customers over the phone line to the call center or reported by SCADA telemetry.

Implementation Program

Currently the control of the HV/MV electrical network is achieved from 12 dispersed control centers. The implementation of the new SCADA/DMS system will enable a gradual concentration of these control centers. The target is that within three years, the HV network will be divided into two areas and the MV electrical network will be divided into four different geographical areas.

EDP expects the transition from the existing SCADA systems to the new SCADA/DMS should have a reduced impact on operation. After the installation of the new system, some of the previous workstations will remain on the existing SCADA platform. This will allow for the gradual transition to the new SCADA/DMS system and assure the simultaneous operation of the two systems.

The software architecture supports a distributed heterogeneous environment where servers and workstations may be based on UNIX or WindowsNT. EDP Distribution intends to keep the remote control centers in operation that are based on the existing SCADA platform. These workstations normally will be unattended, but in case of telecommunication link failure, they may be activated as an autonomous SCADA system.

In September 2001 a remote control center was installed in Lisbon. EFACEC installed equipment that integrated with the GIS/SW system that works in parallel with the existing SCADA system controlling 20 HV/MV substations. In addition to the conventional SCADA functions, the installed functions include:

  • Geographical and schematic diagrams for the operation of the HV/MV electrical network

  • Management of the operational state of the network with the help of a tagging subsystem

  • Network coloring and tracing features.

This installation has allowed the control room staff to get acquainted with the new system. It has also been collected improvement proposals and achieved the validation of the functions that gradually have upgraded the system. Equipment validation continues, and by the end of 2002, the following systems should be tested and approved:

  • Automatic updating of the SCADA/DMS database from the GIS Smallworld

  • Hot-standby operation of the duplicate DMS server.

  • Installation of a duplicate Historical Information Management server

  • Switching orders and safety checks

  • Power applications (power flow, short-circuit calculations, load allocation, load forecast and state

  • Estimator

  • First-stage integration between SCADA/DMS and the new outage management system (Power On).

Following the final validation of the EFACEC equipment, the installation program will proceed until the end of 2004 with the installation and commissioning the four EDP Distribution Remote Control Centers — Lisbon, Oporto, Setúbal and Coimbra. This program will run in parallel with the activities related with the electrical network data capture for the Smallworld GIS aiming to cover the total HV/MV electrical network.

Forging Ahead

The implementation of the new SCADA/DMS system will enable a gradual concentration of the dispersed control center. The goal is to control the HV electrical network from two different control centers within three years. The MV electrical network will be divided into four different geographical areas, each one with its own control center.

EDP will transition gradually from the existing SCADA systems to the new SCADA/DMS system and will undertake simultaneous operation of the two systems in order to reduce the impact on operation.

The EDP/EFACEC experience, in the scope of the current DA project, focuses on a component-based architecture that the utility can extend in an incremental manner to make it an enterprise-wide architecture, linking and integrating the various corporate business processes. A phased approach was followed, and present developments are based on standards such as CORBA from Object Management Group (OMG). Other standardization activities are being evaluated, including the EPRI-CCAPI Common Information Model and IEC-TC57 61968 System Interfaces for Distribution Management.

João Rosa earned a degree in electrical engineering from the University of Lisbon-Instituto Superior Técnico in 1979 and joined Electricidade de Portugal in 1981, participating in the specification, evaluation and commissioning of different SCADA systems. In 1995, he was appointed Telecontrol Department manager in one of EDP's four distribution companies. In 1999, he joined the team project for the implementation of an integrated technical management system for EDP. Since 2000, Rosa has been the SCADA/DMS project manager for EDP Distribution.

Alberto Rodrigues earned a degree in electrical engineering from the University of Oporto 1981 and joined EFACEC Co. in 1983, where he gained experience in real-time applications, automation and SCADA systems. His main technical interests include real-time systems and modern architectures for SCADA/DMS systems.