An Online Security Prediction and Control Framework for Modern Power Grids

Abstract

The proliferation of renewable energy sources distributed generation (RES-DG) into the grid results in time-varying inertia constant. To ensure the security of the grid under varying inertia, techniques for fast security assessment are required. In addition, considering the high penetration of RES-DG units into the modern grids, security prediction using varying grid features is crucial. The computation burden concerns of conventional time-domain security assessment techniques make it unsuitable for real-time security prediction. This paper, therefore, proposes a fast security monitoring model that includes security prediction and load shedding for security control. The attributes considered in this paper include the load level, inertia constant, fault location, and power dispatched from the renewable energy sources generator. An incremental Naïve Bayes algorithm is applied on the training dataset developed from the responses of the grid to transient stability simulations. An additive Gaussian process regression (GPR) model is proposed to estimate the load shedding required for the predicted insecure states. Finally, an algorithm based on the nodes’ security margin is proposed to determine the optimal node (s) for the load shedding. The average security prediction and load shedding estimation model training times are 1.2 s and 3 s, respectively. The result shows that the proposed model can predict the security of the grid, estimate the amount of load shed required, and determine the specific node for load shedding operation.

Techniques of power system static security assessment and improvement: A literature survey

“…At the loads side, demand side management such as optimal load shedding can be carried to relieve overloaded lines and correct buses voltage [ 3 , 118 , 119 ]. In Ref.…”

Artificial Intelligence Techniques for Power System Transient Stability Assessment

“…This shift of balance between RESs and conventional power plants exposes a major downside of the renewables today, which is a reduced system inertia (when less generators with rotating mass are in operation). This reduction of the available rotating mass will have important ramifications on the future security and stability of power system operation [1][2][3]. With the increased proportion of RESs in the generation mix, the problem of reduced system inertia will only increase.…”