With large-scale offshore wind power integration in recent years

Chinese grid operation departments put forward needs for risk assessment of oscillation for offshore wind power integration system. Based on analysis of typical oscillation scenario of offshore wind power integration system by using eigenvalue method

this paper first suggests that stability boundary should be constructed for each specified mode according to its relevant oscillation scenario. Taking sub- and super-synchronous oscillation mode dominated by current control of PMSG as an example

it is proposed to construct a stability boundary by using wing power output and short circuit ratio as parameters. The boundary can be generated by off line eigenvalue analysis of the system. Based on the stability boundary

the oscillation stability margin (OSM) is defined for both steady state and N‒1 contingency state. The OSM can be calculated online based on short circuit analysis of real time power flow and applied for risk assessment of oscillation. A 10-machine and 39-bus case system was applied for validation of the proposed method. Results show that the proposed method is accurate and feasible for engineering application.