Practical minimum load shedding strategy to mitigate voltage collapse

This paper presents a new approach for determining the minimum load shedding to restore the solvability of a power system described by differential-algebraic equations. Through parameterization of a given control strategy (i.e. control direction in parameter space), the continuation method is applied to find the equilibrium point associated with the system post-contingency boundary. Then, the invariant subspace parametric sensitivity (ISPS) is used to determine the most effective control strategy so that a practical minimum load shedding can be derived. The system adjustments that could further reduce the minimum load shedding, such as rescheduling of real power generations and changing of generator terminal voltages are also investigated The approach is illustrated with the New-England 39-bus system and the reduced Iowa 162-bus system.