Optimal Power Systems Restoration Based on Energy Quality and Stability Criteria

Francisco Quinteros,Diego Carrión,Manuel Jaramillo

doi:10.3390/en15062062

Abstract

Electric power systems (EPS) are exposed to disconnections of their elements, such as transmission lines and generation units, due to meteorological factors or electrical failures. Thus, this research proposes a smart methodology for the re-entry of elements that have been disconnected from the EPS due to unforeseen events. This methodology is based on optimal AC power flows (OPF-AC) which allow verifying the state of variables such as voltage, angular deviation, and power (these variables are monitored in normal and fault conditions). The proposed study considers contingencies N-2, N-3, N-4, and N-5, for which the disconnection of transmission lines and generation units are carried out randomly. The analysis of the EPS after the disconnections of the elements is carried out by means of the contingency index, with which the impact that the disconnections of the elements have on the EPS is verified. In this way, the optimal route is generated to restore the elements that went out of operation, verifying that when the elements re-enter the acceptable limits, voltage and voltage angle are not exceeded. According to the results of the methodology used, it was found that NM contingencies can be applied in the proposed model, in addition to considering stability restrictions, modeled as restrictions on acceptable voltage limits, and a new restriction for the voltage angle between the differences of the bars.

Highlights

Nowadays, electrical power systems (EPS) are a fundamental part of the modern world since they are responsible for providing the electricity supply by supplying electricity for commercial, industrial, and residential users
Once the power flow has been performed in the EPS, the Contingency index (CI) is determined using the power flow in the transmission lines, and the events that produce more damage to the electrical system were determined; that is, the CI is considered with the highest value
The simulation was carried out using an interface between Gams 27.3 and Matlab R2021b, the algorithm was implemented in Matlab, which is in charge of processing the input data, and the results were returned by

Summary

Introduction

Electrical power systems (EPS) are a fundamental part of the modern world since they are responsible for providing the electricity supply by supplying electricity for commercial, industrial, and residential users. Power outages affect a wide variety of institutions and departments, and among these, there are some considered of high importance: those that must have continuous electricity supply such as police, military and fire departments, hospitals, clinics, and health care centers. There are factors that affect the EPS which cause it to stop supplying the electricity, such as connection and disconnection of loads and generation units, meteorological phenomena such as lightning, and bad maneuvering of EPS operators. The presence of these events generates disturbances in the electrical system causing oscillations, overvoltages, and overcurrents; in addition, it causes elements such as transmission lines, generators, and loads to be out of operation. The disconnection of transmission lines, generators, and loads can cause loss of stability in EPS and a disconnection cascade effect in most elements, which would lead to a partial or total blackout of the EPS [2–5]

Methods

Results

Conclusion