Improving Electrical Insulation Systems Using Smart Grid Technology
For a downloadable copy of this newsletter, please visit the IEEE Smart Grid Resource Center.
By James Pilgrim
The Smart Grid Newsletter this month has been produced by members of the IEEE DEIS Technical Committee on the Smart Grid, with an aim to highlight a range of ways in which Smart Grid is able to help drive innovation and answer long term questions.
By James Pilgrim
For many years, calculation of the thermally permissible loading on transmission circuits was achieved using:
- Standardised calculation procedures based on relatively simple electrical/thermal models of the circuit
- A set of assumptions about the thermal environment in which the circuit was operating; often defined for the different seasons of the year.
The combination of these simplified models and often conservative assumptions led to generous safety margins for the rating itself. This provided network operators with lots of flexibility, and helped to ensure that system constraint costs associated with limits on power flows were relatively modest.
By Gian Carlo Montanari, Robert Hebner, and Paolo Seri
There are various approaches regarding the meaning and added value of the Smart Grid concept. As a general definition, the digital technology that allows for two-way communication between the utility and its customers, as well as sensing throughout the transmission and distribution systems, is what makes the grid “smart”. This means mostly, at present, monitoring energy consumption and flow, actuating automatic rerouting when equipment fails or outages occur for quicker restoration of electricity after power disturbances, and improving integration of customer-owner power generation systems, including renewable energy systems. However, if the final objective is more efficient transmission and distribution of electricity and increased reliability, a fundamental contribution can be provided by implementing advanced techniques for diagnostic and condition monitoring of electrical apparatus, in order to achieve dynamic information on electrical apparatus health conditions and their optimum operation. Since, generally, the weakest points of the apparatus are the insulation sub-systems, detection of diagnostic properties able to evaluate their aging and failure probability is vital for reliable grid operation.
By Thomas Andritsch, Giovanni Mazzanti, and Jérôme Castellon
High voltage direct current (HVDC) cable systems are traditionally the best solution for long-distance submarine transmission, but are not very common on land. However, the improved performance of AC/DC converters, in terms of cost and power throughput, and public concerns for the environmental and visual impact of overhead lines, are making HVDC cable technology more and more appealing. Indeed, it is generally believed that the increasing penetration of HVDC cable transmission will make the world grid smarter, fostering flexibility, reliability, and sustainability by integration of renewables, which are often far away from load centers. This has led to a near exponential growth of HVDC cable lines worldwide in the past two decades.