Stochastic Economic Load Dispatch Under Supply and Load Uncertainty - A Case Study on Modified IEEE 5 BUS Power System

Abstract

Background: In the contemporary world, the use of energy, especially electrical energy, is increasing rapidly. Without this power, modern civilized life cannot think for a moment. Thereby a huge amount of electrical energy is needed. We have to generate a considerable amount of electricity to meet the growing demand maintaining necessary conditions and constraints. A rapid divergent strategy called Economic Load Dispatch (ELD) has been introduced to distribute generated energy economically during times of crisis. The problem of economic load dispatch is solved with the help of Optimal Power Flow (OPF) formation. The OPF is a primary tool related to the optimum generation schedule available in an interconnected power system to reduce production costs subject to the limitations and constraints of the relevant system. The static economic dispatch optimizes over single dispatch intervals, which is called “ED static”. Due to high load variability and uncertainty, the ED-static is not working properly. Thereby a deterministic look-ahead dispatch is established, which takes care of the increasing renewable penetration. To take decisions against uncertainty, stochastic load dispatch is required. In this research paper, an economic study of the modified IEEE 5 bus power system will be presented. Moreover, some intelligent changes to this system will include the goal of reducing costs, including maximum power supply. The optimal power flow of the modified IEEE 5 bus system considering plausible scenario will represent based on stochastic load dispatch optimization model. Methods: The extension version of Economic load dispatch where load flow equations are applied, and as a system of supply-demand balance constraints is called optimal power flow. To solve the optimal power flow Lagrangian method is used. Karusk-Khun-Tucker (KKT) conditions are applied to solving the Lagrangian method. Results: The results show that during uncertainty and stochastic loads, the storage system with renewable power and generator is suitable for cost reduction with maximum supply. Conclusion: The results further show that for any type of loads, such as fixed load and stochastic load in IEEE 5Bus system, if both renewable energies, such as wind power, solar power, the storage devices are used in the generation system, which ensures maximum power supply with the cost is reduced.