Fault Location in Power Networks Using Synchronized Phasor Measurements

Faults in electric power systems can lead to cascading power outages which cause tremendous loss to the economy and affect people’s lives. Technical reports of recent blackout events in the United States pointed out the lack of situational awareness as one of the main causes of widespread outages. Time synchronized phasor measurement is recommended as a technology that can improve the monitoring of power system condition. By knowing exactly where a fault occurs, necessary actions can be taken in a timely manner and thus, damage caused by that fault can be limited. In this thesis, first, a method for precise frequency and phasor measurement is proposed. This novel method bases on the linear combination of selected Discrete Fourier Transform terms and is able to eliminate estimation error at off-nominal frequency. Second, the thesis presents a method to locate fault in power network using voltage and current phasor measurements. This fault location method involves the calculation of impedance matrix when network topology changes during fault and fault location is found by matching the calculated values of voltage and current phasors with its real world measurements. The proposed method is implemented in MATLAB and is demonstrated in three example networks simulated in PSCAD