A Rapid Fault Section Location Method for Hybrid Overhead and Underground Power Transmission Lines Based on Fiber Bragg Grating Current Sensors

In response to the contradictory reclosing strategies following faults in current hybrid overhead and underground power transmission lines, this paper proposes a rapid fault section location method for hybrid power transmission lines based on Fiber Bragg Grating (FBG) current sensors. Initially, a front-end FBG sensing unit is customized for accurately perceiving the load current of the power transmission line, based on magnetostrictive materials (GMM). It collects current signals in real-time and calculates the Cross Validation Mean Square Error using a cascade model of K fold cross validation, Particle Swarm Optimization (PSO), and Long Short-Term Memory (LSTM) networks as the measurement error, thereby achieving temperature compensation. Subsequently, the fault frequency current collected by the FBG current sensor is analyzed to calculate the Pearson coefficient, and the fault section is determined by combining the waveform similarity comparison algorithm based on Pearson correlation. The effectiveness and accuracy of this method are verified by comparing actual line inspection records.