Maximum Variation of Asynchronous Generation in Power System Based on Rotational Inertia and Frequency Response

This work describes the effect of increasing penetration of asynchronous generation on rotational inertia and frequency response of power system. It is shown that the both system inertia and frequency bias tend to be lower, as the penetration level is higher. Higher variations of frequency are of concern. It is proposed to determine the maximum allowable variation of asynchronous generation, without violating a constraint of frequency deviation. The maximum variation, not the penetration, can be assessed from quantifying system inertia and frequency bias after integrating asynchronous generation into power system. The assessment method is explained and discussed by using an illustrative example.