Standard tests and requirements for rate-of-change of frequency (ROCOF) measurements in smart grids

Improved measurements of rate-of-change of frequency will provide vital support to the smart grids of the future

The Renewable Energy Directive requires the EU to fulfil at least 20 % of its final energy consumption with renewable sources by 2020. Future electricity networks incorporating such a large proportion of renewable sources are subject to intermittent generation and require new instrumentation that can successfully balance supply and demand to prevent blackouts and poor power quality. Rate-of-change of frequency (ROCOF) is an essential measurement that such grid control systems depend upon to ensure the continuity and quality of electricity supply. However, ROCOF measurements are challenging, as they are highly susceptible to the disturbances experienced in typical electricity networks. Many measurement techniques have been proposed, yet despite the vital nature of this parameter, no appropriate standardisation for ROCOF testing exists. This project has built on the achievements in EMRP projects ENG04 SmartGrid and ENG52 SmartGrid II to review, develop and optimise algorithms to measure ROCOF over the full range of network conditions, and develop compliance test protocols, to support the development of a ROCOF standard.