A gas-thermal inertia-based frequency response strategy considering the suppression of a second frequency dip in an integrated energy system

Increasing access to intermittent new energy in the power grid reduces system inertia and exposes the power system to severe frequency stability problems. To address this issue, this study fully exploits the slow-dynamic characteristics in gas-thermal systems of the integrated energy system to provide frequency response. Given the characteristics of both being able to provide buffer space for energy fluctuations, this study gives definitions of gas-thermal inertia and explores their similar power shortage support potential. Then given the necessity of thermal recovery on the load side, a gas-thermal inertia-based frequency response strategy is proposed with help of gas inertia to suppress the second frequency dip. The frequency response model presented in the paper also offers an opportunity to weigh the frequency response effect against the total economic benefit. The proposed strategy is tested in an actual scenario, and the effectiveness of second frequency dip suppression is tested. •Gas-thermal inertia's ability to resist power fluctuations is presented.•A gas-thermal inertia-based frequency response strategy is proposed.•The strategy performance of controlling response effects is presented.•The strategy performance of suppressing second frequency dip is verified.•Advantages of gas inertia participation in frequency response are illustrated.