Evaluation of the Power System’s Connection Capabilities Using Nonlinear Optimisation with Simulated Annealing

This article presents nonlinear optimisation as a tool for determining the maximum power output of renewable energy sources connected to the transmission grid. The goal of the developed model is to maximise the total power generated by these sources while taking into account the technical and operational constraints of the system. These include permissible load on transmission lines and transformers, cross-border exchange balance limits, and the “must run” limits for the operation of conventional power plants. Particular attention was paid to meeting the N-1 safety criterion, which assumes the system’s resilience to infrastructure failures. Appropriate conditions for post-failure states were incorporated into the set of optimisation constraints. A heuristic simulated annealing algorithm was used to solve the problem, enabling the search for globally optimal solutions in a discontinuous and highly nonlinear space. The calculations yielded a generation vector for renewable energy sources connected to individual grid nodes, thus ensuring maximum utilisation of the available renewable energy potential under the given system conditions. The effectiveness and efficiency of the proposed approach are illustrated with the example of a test network.