Optimization and Validation of Distributed Generation Integrated Load Flow Scheme for Congestion Management of Interconnected Transmission Systems

In response to scheduled or unscheduled disruptions, energy supply organizations extensively employ distributed generators (DG) to fulfil increased power demands. The expansion of transmission and distribution networks, coupled with line interruptions, contributes significantly to transmission line congestion within interconnected systems. Addressing and mitigating congestion is essential for ensuring the reliable and efficient operation of a power network. This chapter explores the potential of distributed generation (DG) to alleviate congestion within interconnected transmission systems. It places significant emphasis on devising a dependable approach to determine the optimal locations and sizes for integrating local generators to relieve congestion, as it is a crucial requirement. The research aims to develop a straightforward and trustworthy strategy for the placement and sizing of DGs within a transmission line system, utilizing power flow analysis. The initial analysis is conducted on the 14-bus IEEE system to identify parameters for assessing congestion severity and determining the ideal DG locations and sizes. Load flow algorithms in ETAP software are utilized to assess power flows under various line outage scenarios in the 14-bus IEEE system. The results indicate that the percentage violation of the system is a critical parameter for evaluating congestion in interconnected systems. The study further examines the application of two indices, the Severity Index (SI) and Sensitivity Factor (SF), to identify the optimal DG placement and capacity for congestion alleviation. A reliable algorithm based on these indices is proposed to guide DG placement and sizing decisions. This methodology is grounded in system indices and relies on load flow analysis. The proposed algorithm offers swift and accurate simulation results with minimal approximations, ensuring comprehensive optimal solutions within a shorter simulation time and enhanced convergence probability, leveraging a mathematical approach. The feasibility of this proposed methodology for determining optimal DG placement and quantification in congestion solutions is assessed using a practical interconnected bus system within the Kerala grid. This methodology is transferable and can be adopted by transmission system operators in similar connected systems worldwide. It effectively identifies severe congestion cases and recommends the best locations and sizes for DGs to manage congested feeders within the grid system. Finally, the analysis of system losses for various DG penetration scenarios through load flow analysis validates the obtained results.