Dynamic estimation of rotor angle deviation of a generator in multi-machine power systems

This paper introduces a new approach to obtain the generator rotor angle difference in the multi-machine power system for transient stability studies. It aims to replace the center of inertia (COI) for on-line transient stability assessment. Compared with COI, the proposed method can give more reasonable estimations of rotor angle difference between the individual generator and the multi-machine power system. In addition, it allows generators to have their own references for evaluating transient stability, which is more reasonable and accurate than using COI. Moreover, the proposed technique calculates the rotor angle difference by using the local generator's active and reactive power output. This does not add any extra burden to the communication channel.

► This paper has demonstrated the feasibility of COI for power system transient stability studies.
► This paper introduced a new way to replace the COI for obtaining the rotor angle difference between single generator and the multi-machine power system.
► The proposed method only requires local generator's active and reactive power output.
► The proposed method can be used with transient stability assessment, stability constrained optimization and control.