Inertia Response of Power System Frequency Dynamics Based on The Quadratic Eigenvalue Approach

With the high penetration of renewable energy into the power system and the development and application of power electronic devices, the operation scale of the power system is increasing. Meanwhile, the frequency dynamic behavior of the power system is becoming more complex, which urgently needs effective frequency stability analysis methods and control means. To overcome the computational errors in the traditional system frequency response model, we established a frequency response model based on the full-state model of the power system. First, through the analytical solution of the time domain response of the state variables, we obtain the quantitative relationship between the system frequency-related characteristic quantities and the system parameters. Then, we transform the frequency stability problem into the quadratic eigenvalue problem and demonstrate that the reduction of system inertia increases the imaginary part of eigenvalues, which reduces the disturbance rejection capability of the system frequency inertia response. Finally, the correctness and validity of the above conclusions and methods are verified in the 10-machine 39-node system.