Partial Discharge Location In Transformer Simulation Based On Principles Of Phased Array And MUSIC Algorithm

The power transformer is one of the important equipment in the power system, the condition of insulation directly affects the safe operation of power system. With the development of power system and the increase in voltage, so the Partial Discharge(PD) has become one of the main reasons of the insulation degradation of the power transformer. so detection of the PD is the important method of the transformer insulation condition. so improve the accuracy of partial discharge point positioning can largely ensure safe and reliable operation of power system. Experience has shown that real-time detection of transformer operating conditions can guarantee the security and stability of power system security.This thesis focuses on the accurate positioning of PD points of power transformer into the improved MUSIC algorithm based on UHF and ultrasonic phased receiver principle of partial discharge location method,combined with the use of MATLAB software to complete the simulation.First, Partial discharge point will be regarded as ultra-high frequency and ultrasonic emitter, Used the planar phased array sensor composed of detected ultra-high frequency and ultrasonic signals, Use the received UHF signal as the time base. Get the time delay in the same direction of ultrasonic transmission. Calculate the distance between the partial discharge point and sensor.Then, analysis with improved MUSIC algorithms use the received the ultrasonic signal of ultrasonic sensor. Then, Improved MUSIC algorithm is used to receive data covariance matrix isolated signal subspace and noise subspace, the signal steering vector and noise subspace orthogonal composition scan spectrum, signals of the number, pitch angle, direction angle and the angular spectrum value The parameter estimation.The simulation results showed that:the error of Simulation distance is small and the accuracy of simulation results is high. Can effectively distinguish the arrival angle of coherent signals. Realize the accurate parameter estimation of number of signals, the pitch angle, direction angle and its angular spectrum value. And verify the accuracy of improved MUSIC algorithm. It has high sensitivity, precision and angle of resolution angle estimation.Can be used for multiple non-coherent sources to estimate wave direction, and has high precise, fast and accurate.