Opportunity for synchrophasors in monitoring sources of renewable energy integrated into distribution networks

Abstract

Synchrophasor measurements have traditionally been reserved for monitoring the operation of transmission systems. This technology enabled direct supervision over transmission system operation without any complex estimation modelling. As a result, system operators could better manage the operational stability in transmission systems. With significant developments occurring in distributions networks, specifically the integration of renewable power plants (RPPs), synchrophasor monitoring at distribution level have become of interest. Distribution network operation generally have smaller voltage phase angle di erences, which would require higher metrological capabilities in synchrophasors. The concept of high-precision synchrophasor measurements with time synchronisation accuracies better than a -second is known as a micro-synchrophasor. High-resolution recording capabilities of micro-synchrophasors enable the detection of voltage phase angle o sets between two locations at fractions of a degree. This research demonstrates the usefulness of the micro-synchrophasor to quantify the interaction between a PV power plant and the distribution network it integrates with, which would provide a better understanding on the impacts of RPPs on distribution networks. The metrological capabilities of the recording instruments used in this research were first tested and verified for micro-synchrophasor level recordings. During the tests, the practical viability of micro-synchrophasor measurements were also validated. After the tests, micro-synchrophasor field recordings were performed at a 75 MW PV power plant feeding into a kV distribution grid. The field data was then used to visualise the steady-state and voltage stability levels between the PV plant and upstream distribution station over a period of 24-hours. Results were analysed to study the impact of a RPP integrated onto a distribution network, which demonstrated the opportunity for micro-synchrophasors to monitor renewable energy sources integrated in distribution networks.