Synchronised measurement devices for power systems with high penetration of inverter‐based renewable power generators

The deployment of more and more power electronic devices results in the sub-synchronous oscillation caused by sub/super-synchronous harmonics associated with inverter-based renewable power generators (IRPGs). New measurement devices are needed to monitor the operation states of renewable power generator (RPG) areas. In this study, a synchronised measurement device for power systems with high penetration of IRPGs (SMD-R) is proposed and developed. Unlike traditional synchronised measurement devices, an SMD-R is able to perform real-time inter-harmonics and fundamental phasor estimation that are reported by different data frames in different rates by being installed inside a wind turbine or an integration station of RPG. The integration of SMD-R and the message format for inter-harmonics are outlined. A spectrum line curve fitting based algorithm is proposed to estimate inter-harmonics via a short data window. To track the dynamic process of RPG areas fast and precisely, an adaptive fundamental phasor algorithm based on phasor parameter behaviours identification is developed. The proposed SMD-R is implemented in a CompactRIO of National Instruments. Experiment results verify the accuracy and effectiveness of the proposed device.