A System Made Up of Systems
The Smart Grid seeks a standard.
Europe aims to have established a smart grid by 2020. The decentralized system integrates not only energy production and distribution, but also consumers. Real-time bidirectional communication between the network management systems and a high degree of automation, information processing, and data security are imperative. To implement these criteria, all parties involved must agree on a common standard.
The smart grid not only requires special investments, it will also bring savings. According to a study, intelligent network management could result in a 13% reduction in total electricity costs, equivalent to an amount in the double-digit billions. To achieve this, new components, which are suitable for use in smart grids and offer comprehensive real-time measurement and control functions, must be integrated into the existing networks. A smart grid requires a data network in addition to the electricity grid.
Embedded systems, i.e., components with processors that can process signals independently, play a particularly significant role in this context. While these systems have been used for decades in the automation of industrial control systems, the present challenge lies in implementing smart grid-enabled communication systems and end-to-end networking of the control systems up to the grid control center via Ethernet. This in turn may involve risks in the areas of industrial and data security, not least in view of the continuous development of new malware, including trojans, which can be used for cyber sabotage.
Electricity Grid Still Largely “Uncommunicative”
In view of the above, addressing the key issues—conformity, interoperability, safety, security, and usability—at an early stage is all the more important. Interfaces, protocols, mapping, and communication should be standardized as they must reliably fulfill uniform requirements. The IEC 61850 standard describes the criteria for the exchange of information—an area where the stakeholders still have plenty of catching up to do in practice.
In Germany, mainly high-voltage networks have been designed in accordance with the IEC 61850 standard, while the number of devices enabled for this standard is still insufficient in the medium and low-voltage sectors. The current electricity grid comprises around one million sub-stations, only one-third to one-quarter of which comply with the communication standard at present, i.e., are “enabled for communication”. Grid operators thus face the challenge of having to convert the entire infrastructure into a smart grid, while equipment manufacturers must develop and supply devices, which reliably fulfill the requirements of the IEC 61850 standard and are capable of communicating securely with each other. Initial regional pilot projects still reveal a high degree of incompatibility.
On its own, a certificate of conformity in accordance with the standard is no guarantee that the devices of various manufacturers are actually compatible in practice. The IEC 61850 communication standard is to become the backbone of the smart grid. It defines the principles of Ethernet-based data transfer between electricity producers, consumers, and distributors.
The standardized data models and nodes provide for easy establishment of a well-functioning overall system. This system permits both comprehensive data communication between the connected components and largely automated utility grid management. Further advantages of a system based on the IEC 61850 standard include its modular structure and simple configuration via XML files. These systems further offer interfaces with the standardized IEC 60870-5-101 or 60870-5-104 telecontrol protocols to be gradually replaced by IEC 61850. This facilitates grid integration of both existing plants and new components. Given this, adopting the standard may also be of advantage for the industry and manufacturers.
Quality Assurance for Components
So far, know-how concerning the ideal integration of both built and new systems into smart grids still offers room for improvement. However, external expertise such as independent tests verifying the usability of technical components is also helpful at component level. Plans provide for conformity testing to be rounded off by practical performance and interoperability tests for sensors, actuators, signal generators, security devices, or smart meters. The tests must be carried out on the basis of edition 1 and edition 2—the latter soon to be available in full by end of 2012—of the IEC 61850 standard. These tests provide power producers, consumers and grid operators with reliable guidance on the selection of individual devices and their integration.
Given this, the provision, quality and security of the required information are a key to the smart grid from a broader perspective than that of consumers. Grid owners and operators will also request information from all energy producers connected to their grid. This may prove a complex task for smaller energy producers without specialist know-how. They must consider the technical requirements they have to fulfill right from the outset when planning a new plant. The owners and operators of existing plants should inform themselves in a timely manner about the upgrades that are required for integration into the smart grid and how to realize such upgrades in the most cost-effective manner.
TÜV SÜD’s Smart Grid Competence Centre supports companies throughout the world, providing across-the-board strategic consulting services from planning to implementation. Technical testing of components and systems carried out in TÜV SÜD’s in-house smart grid testing laboratory makes up the second service segment. In addition to laboratory testing of the conformity and interoperability of devices and systems in accordance with the IEC 61850 standard, the service portfolio also comprises comprehensive consulting services on the design and development of new devices, the integration of components and systems into the smart grid and smart grid optimization as well as special training offers for electricity producers and consumers.
Author's Bio: Christian Dirmeier is Product Manager of Smart Grid Embedded Systems at TÜV SÜD.
Peter Pfisterer is head of the Smart Grid Laboratory at TÜV SÜD.