Frequency Response Assessment of Inverter Dominated Power System Under Grid Abnormalities

The increase in renewable sources equipped with power electronic converters can pose a serious threat to power system stability. This paper presents the grid frequency response observed after integrating inverter-based resources into the dynamically focused synchronous generator-based IEEE 9 bus system. The inverter current and voltage control strategies of the grid following mode is implemented, and the inverter response to grid disturbances such as faults, phase jump, voltage sag-swell, and harmonics are observed. The rate of change of frequency, inertia, voltage stability, and transient stability are examined with different inverter penetration levels. The effect of load power factor on the power voltage curve is also analyzed. The data from MATLAB-SIMULINK is utilized to evaluate the performance of inertia estimation and various stability methods.