Calculation of the critical clearing time considering variations in the equivalent inertia constant

• Grant number: 18/25853-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2019
• End date: August 01, 2020
• Field of knowledge: Engineering - Electrical Engineering - Power Systems
• Principal Investigator: Rodrigo Andrade Ramos
• Grantee: Julia Reis Céu
• Host Institution: Escola de Engenharia de São Carlos (EESC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Associated scholarship(s): 19/11703-9 - Evaluation of the influence of equivalent inertia variations on power systems using stochastic simulations, BE.EP.IC

Abstract

The stability analysis of Electric Power Systems (EPS's) is an area of great importance and notoriety due to the interconnection of the electrical systems. This analysis ensures a safe operation of the system, since the occurrence of instability may lead to malfunctioning of electrical machines and equipment connected to the network. Short circuits are the main causes of disturbances in the systems, as it is difficult to predict and avoid them because of their randomly occurrence. In addition, the general concern about sustainability has led to the share of renewable energy sources increment for the past years in energy systems. Thus, in order to guarantee the stability of the EPS's, new study approaches are necessary to predict their behavior while a short circuit is happening, since such alternative sources cause a decrease in the system's equivalent inertia. As the differential equations that describes the systems are non-linear, and dealing with great disturbances in the study of transient stability, the stability evaluation should be done through numerical simulations. Thus, this research proposal has as main intention to seek improvements in the protection system of EPS's with a probabilistic treatment of rotational inertia, which influences the system modeling. By performing a careful analysis of the distribution of the critical opening times generated by numerical simulations, taking as input a defined continuous distribution of possible inertia values and a fixed fault location, it is possible to define a maximum time over which the protection must act to isolate the fault and keep the remaining system still on stable operation, preventing the disturbance from affecting a larger part of the network. In this way, it is possible to determine more precise adjustments for the system protection by considering a more adequate modeling of the parameter variation.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

CEU, JULIA R.; JONSDOTTIR, GUDRUN M.; MILANO, FEDERICO; RAMOS, RODRIGO A.; IEEE. On the Impact of Non-Synchronous Devices over the Critical Clearing Time of Low-Inertia Systems. 2020 20TH IEEE INTERNATIONAL CONFERENCE ON ENVIRONMENT AND ELECTRICAL ENGINEERING AND 2020 4TH IEEE INDUSTRIAL AND COMMERCIAL POWER SYSTEMS EUROPE (EEEIC/I&CPS EUROPE), v. N/A, p. 6-pg., 2020-01-01. (18/25853-0)