Abstract
The problem of Electricity are enormous and can never be treated completely until the fault department (maintenance) are improved upon for urgent and rapid response to line faults. The present protection scheme only isolates the lines in the event of faults, define the fault, but leaves no proper information about the location of the fault. Faults must occur on both the transmission and distribution lines but, the problem is how fast can the fault be cleared when the maintenance team have to patrol the lines (ie from pole to pole and from tower to tower) looking for the fault(s). in this research, fault location based fuzzy logic is developed. The proposed fuzzy logic based technique has less computation complexity. Real transmission system parameters of 400 kV Wardha – Aurangabad transmission line, India (400 km) with 40% compensation at one end are implemented for this research. Percent absolute error is calculated for performance evaluation of the proposed method. Large numbers of test cases are generated which provide complete distance protection scheme giving quite accurate results with percent absolute errors mostly within 2.75% demonstrating more accuracy as compared to previous fuzzy based fault location schemes, least complexity and robustness of the proposed technique.
CHAPTER ONE
INTRODUCTION
1.1 Background to the study
The reliable operation of large power systems with small stability margin is highly dependent on systems and protection devices. The application of microprocessor based (numeric) relaying protection has improved performance over time but, this has not led to a major impact on speed, sensitivity, and selectivity of primary protective relays. However decision making based on elements of artificial intelligence (AI) can, in my view, lead to a major impact in the aforementioned especially as quick fault removal in lines maintenance is concerned here. Series compensation is majorly applied in modern power system for achieving maximum power utilization of existing transmission system and improving the overall performance of transmission systems. Series compensation comprises of capacitor bank protected by a metal oxide varistor (MOV) and a spark-gap arrangement. The nonlinear behavior of such series capacitors and its protection equipment during fault disturbances influences the current and voltage signals. This in turn creates problems to relay operations. Accurate detection, classification and accurate location of faults on a transmission line are crucial for relaying decision, removal of faulty sections in the system and quick repair for availability.
