Dağıtım sistemlerinde röle koordinasyonunun uygulanması

---

Thesis Type: Postgraduate

Institution Of The Thesis: Yildiz Technical University, Graduate School of Natural and Applied Sciences, Elektrik Mühendisliği, Turkey

Approval Date: 2023

Thesis Language: Turkish

Student: AMIR AZIZ YAHYA ALMODAFER

Principal Supervisor (For Co-Supervisor Theses): Erdin Gökalp

Co-Supervisor: Yavuz Ateş

Open Archive Collection: AVESIS Open Access Collection

Abstract:

This study introduces a novel mathematical approach for analyzing the selection of parameters that ensure the correct coordination of overcurrent relays (OCR). The study assesses the dependability of commonly cited concepts in the literature on optimization overcurrent relay coordination (OCRC), including the objective function (OF) for finding the minimum relay tripping times and the belief that the coordination time interval (CTI) constraint is critical for valid OCRC. The study was conducted on three types of networks: radial, multi-source radial feeding, and ring networks. The radial network model was the Hemdan substation in Abu Al-Khaseeb, Basra, Iraq; the ring network models were the IEEE 3 bus and IEEE WSCC 9 bus systems; and the multi-source radial feeding network model was the open IEEE 3 bus. The study tested the accuracy of OCRC using the three protection criteria of selectivity, speed, and security, rather than just the OF and CTI. The results were validated using five optimization algorithms tested on MATLAB and ETAP: linear programming (LP), genetic algorithms (GA), biogeography-based optimization (BBO), a BBO-LP hybrid, and population-based incremental learning (PBIL). For all algorithms, the radial network study compared eight operational scenarios with three photovoltaic stations (PV) connected at different distribution network sites. The widely accepted approach of preserving the CTI constraint while comparing optimization algorithms based on the lowest OF value was found to be flawed in this study. It highlights the incapability of directional overcurrent relay coordination (DOCRC) in ring-fed networks and its infeasibility in multi-source radial-fed networks. A dynamic OCRC mechanism is proposed for a radial network, utilizing a successful optimization algorithm selected from five candidate algorithms. For a ring network, a coordination approach is suggested to divide it into islands based on load flow while taking into consideration the connection of PV systems.