Power Imbalance Mitigation by Grid Impedances under Multiple-Point Inertial Responses of Generations with Different Power Points

This paper investigates power imbalance mitigations by grid impedances under multiple-point inertial responses of non-synchronous generation (NSG) with positive and negative power points. Firstly, an inertial normalization method is put forward to unify inertia time constants at the same base of kinetic energy for all generators. Then, a network reduction method is applied to converter complex network topology to simpler radial form with one center point for the ease of grid impedance losses analysis. Next, a novel theory is established to analyze total grid impedance losses under multiple-point synthetic inertial responses of NSG with different power points when being subject to same rate of change of grid frequency, which implies that heavier total inertia in the generation with negative power points (importation) results in grid impedance losses variations to counteract overall grid imbalance. This conclusion is effectively validated verified in the model of IEEE 3 machine 9-bus system.