Optimal frequency determination for wind-hydro hybrid unit using Telegrapher's method for low-frequency transmission lines

This study addresses the optimal load flow problem for low-frequency transmission lines connected to wind farms and Pumped Storage Hydropower (PSH). The losses in the LF-HVac system and the voltage stability index are highly reliant on the operating frequency. Hence, it is essential to integrate an Optimal Load Flow (OLF) method in order to ascertain the appropriate solutions for these systems. The load flow solutions in this system involve the utilization of the Newton-Raphson method in conjunction with STATCOM. A proposed approach to simplify mathematical calculations involves the development of a two-port equivalent model for transmission lines. This model is based on solutions derived from the Telegrapher's method. The OLF method, which has been proposed, has undergone testing with various algorithms and has been successfully implemented in the IEEE 39-BUS system. The obtained results demonstrate that the LF method, when combined with the proposed metaheuristic algorithm, achieves optimal frequency for low-frequency HVac systems while simultaneously ensuring system stability.