A Fast Dynamic Optimization Approach for Transient Stability Emergency Control

The transient stability emergency control is able to select the proper strategy of generator tripping or load shedding to maintain power system transient stability after a large disturbance. It can be modeled as a dynamic optimization problem, which is computationally expensive. In this paper, a constraint aggregation based dynamic optimization approach is proposed to solve the problem. In this approach, the differential algebra equations (DAEs) are solved outside the optimization problem and the resulting nonlinear programming (NLP) problem is solved by interior point method. The constraint aggregation technique is employed to preprocess the transient stability inequality constraint, and the adjoint sensitivity analysis is adopted to evaluate constraint. Based on the two layered bordered block diagonal (BBD) structure in the Jacobian matrix, a parallel algorithm is developed to improve the computational efficiency. Numerical experiment indicates the efficiency and practicality of the proposed approach.