Siân Green, Managing Editor
As digital devices grow in importance in society, the need for a secure, reliable and high quality power supply increases. In recognition of this, a collaborative research programme has started in the US which includes the development of an advanced, ‘self-healing’ electricity grid.
Power outages and disturbances currently cost the US economy in excess of $119 billion per year, and this value is expected to continue to grow as digital devices proliferate in the economy.
According to the USA’s Electric Power Research Institute (EPRI), these losses illustrate the inadequacy of the current power system. Over the next 20 years, electricity demand in the US is expected to grow by more than 20 per cent, while transmission systems will increase by just four per cent. Further shortfalls are therefore inevitable.
With some 95 per cent of the increase in US productivity over the last five years being the direct result of the emergence of digital devices, the country has recognised the importance of developing an electricity infrastructure that can support this new economy. The security, quality, reliability and availability of power systems are becoming ever more important.
Recognising this, EPRI, together with its supporting non-profit research and development organization, the Electricity Innovation Institute (E2I), has launched a new initiative – the Consortium for Electric Infrastructure to Support a Digital Society (CEIDS).
Jointly managed by EPRI and E2I, the objective of CEIDS is to provide the science and technology that will support a digital economy. The programme brings together an array of private, governmental and international organizations and its partners include Electricité de France, Alliant Energy, Bonneville Power Administration, Polish Power Grid, TXU, UTC Power and others.
CEIDS’ vision is long-term. It is a $250 million, four-to-five year collaborative research initiative with a strategic focus. Its aim is to develop technology and infrastructure for the 5-15 year horizon, and is funded by EPRI member utilities, non-utility industries (such as semiconductor manufacturers) as well as state and federal governments.
As well as improving the reliability and security of power systems, the technologies developed under CEIDS are also designed to increase options for consumers and enhance the efficiency of digital devices. The benefits of the programme will therefore be seen by a range of electricity industry ‘stakeholders’. Specifically, CEIDS will:
- Establish a long-range strategy to ensure that the electric energy industry will continue to provide the quantity and quality of power required by the digital society.
- Enhance stakeholder value by improving asset utilization, system security, reliability and power quality; allowing providers to serve new digital loads profitably and reliably; and leveraging the features of the digital infrastructure for lower costs and higher customer satisfaction.
- Develop new markets via opportunities in distributed resources, DC power, power quality mitigation technologies, and other electricity-related products and services.
EPRI and its partners recognise that to achieve its goals, the CEIDS programme will require the development of a transformed electricity system architecture, which ultimately depends on building new types and levels of functionality into the power system. A number of breakthrough innovations will be required, and EPRI/E2I have identified some of these as:
- Digitally controlling the power delivery network by replacing today’s relatively slow electro-mechanical switching with real-time, power electronic controls
- Integrating communications to create a dynamic, interactive power system as a new ‘mega-infrastructure’ for real-time information and power exchange
- Automating the distribution system to meet changing customer needs
- Transforming the meter into a consumer gateway that allows price signals, decisions, communications and network intelligence to flow back and forth through the two-way energy/information portal
- Integrating distributed energy resources. The new system would also be able to seamlessly integrate an array of locally installed distributed power generation (such as fuel cells and renewables) as power system assets
- Accelerating end-use efficiency through digital technology advances.
A key goal of CEIDS is the development of the technologies necessary to transform the currently electricity grid into an adaptive, ‘self-healing’ power delivery system that can respond to changing conditions such as market-driven operational decisions, external threats to system stability such as weather or man-made risks, shifting distribution of loads, and available transmission capacity.
“Automatic control of a dynamically adaptable ‘self-healing grid’ requires a support system that can model and simulate system behaviour fast enough to anticipate changing system conditions,” said T. J. Glauthier, president and CEO of E2I. “The new system will substantially enhance the grid operator’s ability to analyse dynamic system behaviour for both operational and planning applications.”
In February 2004, E2I and EPRI selected an ABB-led team to develop software for fast simulating and modeling of power system delivery behaviour to support the self healing grid concept. This specific project is known as Transmission Fast Simulation and Modeling (T-FSM), and is broken down into three phases. ABB was awarded the contract to lead Phase I, the project’s research phase, which includes the engineering, software design, and validation and verification requirements for a software system that can provide faster-than-real-time simulation and modeling of electricity grid dynamics over a range of different geographic and time domains. Phase I is slated for completion later this year.
Over the next 20 years, electricity demand in the US is expected to grow by more than 20 per cent, while transmission systems will increase by just four per cent
When it is fully developed, the automated controls of the T-FSM system will anticipate problems and be capable of reconfiguration and self-restoration in response to changing conditions. “We’re very pleased to have this opportunity to develop the IT systems that will fulfill E2I’s vision of an adaptive, self-healing grid,” said Hisham Othman, vice president and general manager of Business Unit Network Management at ABB. “The technologies we’re exploring represent a major advancement from current standards, so it’s very exciting.”
Not all of the specific applications outlined in Phase I will be built, however. Given constraints on time and resources, the ‘dream spec’ will be reviewed in order to select the most promising technologies for development. Phase II will involve the actual writing of code for applications deemed to be most important with others being developed later in Phase III. These development phases will also include .substantial testing.
The T-FSM project is directed towards implementing the information-processing infrastructure to realise a self-healing power grid. The technology that will be developed will be applicable to interconnection of all sizes ranging from small distribution grids to continental-scale transmission systems. This is expected to be a quantum leap in the real time control of interconnected power systems considering foreseeable technologies and challenges in the next decade.
The T-FSM project aims to develop the information-processing technology required for a self-healing power grid
The first phase of the T-FSM project is intended to develop functional and architectural requirements for the information technology infrastructure needed to implement an intelligent electrical grid. This phase started in February of 2004 and is scheduled for completion in 2004. The project team is led by ABB and includes experts from utilities (TVA), universities, vendors (BSI and PW) and the IT industry (HP).
So far, the high-level requirements for the system have been defined. The proposed approach includes a conceptual distributed autonomous real-time (DART) architecture and a set of coordinated closed loop control cycles. The architecture is modular and scalable from the viewpoints of organizational, geographical and functional aspects. The closed loop controls are distributed geographically and are executed at various time scales. The approach calls for autonomous intelligent agents distributed throughout the system at various levels of control hierarchy and responsible for all functional areas relevant to grid operations.
The overall scope of the T-FSM project includes all functional areas of grid management. However, to accomplish tangible results within the schedule of initial phases of the project, the important application of grid voltage and VAr management (V&V) function has been selected as the focus for this work. The execution cycles of T-FSM will monitor, enhance efficiency and reliability, and take control actions in response to power system phenomena in time scales of milliseconds to minutes. This includes detecting potential voltage and VAr problems in advance of their occurrence in near real-time and preparing the grid to take actions to prevent these problems.