The 21st Century Substation Design

(PSERC) is a multi-university Center conducting research on challenges facing the electric power industry and educating the next generation of power engineers. More information about PSERC can be found at the Center's website: Notice Concerning Copyright Material PSERC members are given permission to copy without fee all or part of this publication for internal use if appropriate attribution is given to this document as the source material. This report is available for downloading from the PSERC website. research project titled " The 21 st Century Substation Design. " We express our appreciation for the support provided by PSERC's industrial members. The project industry advisors with affiliations at the time of the project approval were: Many of the US substations are now more than thirty to fifty years old and may be in need of upgrade or replacement soon. The US National Institute of Standards and Technology (NIST) has recently published the smart grid framework release 1.0 document, which was in response to the Energy Independence Security Act (EISA) of 2007 and American Recovery and Reinvestment Act (ARRA) of 2009. A review of these documents indicates a need to develop standards for smart substations of the future. The future substation design requires an understanding how both primary and secondary equipment may interact in the substation, how measurements from the primary system may be converted to secondary quantities by using multifunctional intelligent electronic devices (IEDs), and how the availability of new types of signal sensors may eliminate many of the drawbacks imposed by conventional instrument transformers. The purpose of this study is to create a vision of the future substation. To create this vision, various technical, economical and environmental criteria, such as reliability, cost, interoperability, re-configurability, security, controllability and flexibility need to be considered. Those criteria require use of new design methodologies quite different from the existing philosophy. The design strategies are focused on reducing cost while maintaining the performance, or maintaining cost while improving performance. Based on the considerations mentioned above, three design approaches to meet different scenarios requirements and needs are considered:  Retrofit existing substation design. This approach assumes retrofitting existing substation communication protocol, intelligent electronic devices, power apparatus, and operating standards to improve the overall performance or reduce cost without disrupting the continuity of service. For this purpose, a comprehensive survey of new technologies is done and the cost benefit analysis is addressed. Two scenarios are discussed: upgrading …