Full text
| |
| Author(s): |
Paulo Anderson Holanda Cavalcante
Total Authors: 1
|
| Document type: | Doctoral Thesis |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia Elétrica e de Computação |
| Defense date: | 2016-12-21 |
| Examining board members: |
Madson Cortes de Almeida;
Mário Oleskovicz;
Carlos Alberto de Castro Junior;
Fernanda Caseño Trindade Arioli;
Manoel Firmino de Medeiros Júnior
|
| Advisor: | Madson Cortes de Almeida |
| Abstract | |
Faults are amongst the events that deteriorate the most the power quality and reliability of power systems. These events cause disturbances and unscheduled outages, either temporary and sustained, increasing the operational costs of the electric utilities. The use of fault location approaches in power distribution systems improves reliability and power quality, since it allows faster power supply restoration as well as avoid recurrence of new events. In this way, this work investigates fault location techniques for modern power distribution systems, characterized by the presence of distributed generators and monitoring infrastructure. Two methodologies are presented that allow the use of voltage and/or current magnitude measurements, as well as synchronized and non-synchronized phasor measurements. The first proposed methodology is based on short-circuit theory. In this approach, voltage and current measurements are used to calculate the voltage variations in the whole system, from which a weighted index is calculated for all buses of the power distribution system, allowing the fault location. This methodology includes a refinement scheme that allows the determination of the fault location in branches and buses with good accuracy. The second proposed methodology uses state estimation techniques and a method used in transmission lines. This method require voltages and currents at the two terminals of the faulted branch, which are obtained from proposed state estimators. Pseudomeasurements are proposed to make the networks observable, allowing the estimation of the required quantities. In the development of this methodology, it is assumed the presence of non-synchronized oscillographs of voltages and currents in several points of the network, from which synchronized phasors are estimated. For the synchronization of phasors, a simple mechanism based in sags voltage is proposed. The methodologies were tested for a 13.8 kV real distribution system with 134 buses. In order to make the simulations more realistic, it was proposed mechanisms of inclusion of errors statistically distributed in the main variables that affect the performance of the proposed methodologies. Thus, statistics simulations are adopted in the evaluation of both methods (AU) | |
| FAPESP's process: | 11/19568-1 - Fault Location in Smart Distribution Power Systems |
| Grantee: | Paulo Anderson Holanda Cavalcante |
| Support Opportunities: | Scholarships in Brazil - Doctorate |