623 / 2019-06-04 21:28:05

Protection Algorithm for Medium Voltage Collector Feeder in Wind Farm Based on Discrete Wavelet Transform Algorithm of Current Ratio

Wind Farm, Collector Feeder, Digital Protection Algorithm, WTG, Discrete Wavelet Transform, Internal Faults and External Faults, Sampling Value and Merging Unit .

Owing to the rapid increase of the global population and their energy needs, traditional means to satisfy the burgeoning energy demands need careful reevaluation. This theses present feeder protection relay in digital automated wind farm, the relay uses the sampling value(SV) from merging unit (MU) located at cable feeder and wind turbine generator (WTG) to detect fault (internal) in the collection feeder system or (external) in the grid or parallel feeder, but for these fault the relay remain stable and inoperative, each wind turbine generator and cable feeder has a merging unit acquire current, voltage, and breaker signals for substation automation, the merging unit convert the analogue signal of current and voltage to digital (sampling value), data packets are transmitted over a communication network to the protection relay for protection and control functions of the collection feeder in wind farm. A new digital protection algorithm is proposed in this paper based on. The discrete wavelet transform (DWT) is used to enhance the proposed algorithm performance during fault through high impedance. The DWT is utilized to obtain accurate polarity signal not affected by high impedance. The protection zones are identified where each WTG has its own zone and one zone for the collection cable feeder. The algorithm discriminates between internal faults in the protected collection feeder and external faults in the power grid or any parallel feeders. The proposed protection algorithm performance is verified using various fault scenarios using MATLAB package. The simulated scenarios involved different fault types and locations. The proposed algorithm is applied on a part of Zafarana wind farm which connected to 220 kV network of the unified Egyptian network.