Estimation of Generator Inertia Using Mean Value of Active Power Change After a Disturbance

The reduction of the inertia of power system results from the replacement of Conventional synchronous power plants by intermittent generation. It poses threats to system stability, so that the inertia of power system should be estimated to ensure that sufficient rotated reserved capacity is supplied to maintain system stability. This paper proposes an offline estimation method based on swing equation to estimate inertia of generator after a disturbance. The mean value of generator active power change is utilized to estimate single generator inertia rather than using the value of the first active power after a disturbance. The proposed method improves the estimation accuracy and does not need to know the size of the disturbance. The performance of this method is validated via several cases using the multi-machine system.