Study On The Impact Of GPS Retransmited Jamming On Timing Accuracy Of Power System

With the wide application of GPS technology,whatever the substations,the power plants and the fault location,the characteristics of positioning and timing of GPS has also been used in the electrical power system.The PMU is timed by the GPS clock,so the accurate measurement of PMU is affected by the accuracy of satellite synchronous timing information.This article aims at researching of spoofing GPS receiver clock offset of phasor measurement units.First it introduced the composition of the GPS system and the basic structure of the GPS signal,then acquired the GPS IF signal,studied the GPS signal acquisition,the tracking,the principle of location and the structure of the GPS satellite navigation message.And then the principle of the retransmitted jamming of GPS is researched.It is simulated the retransmitted jamming of GPS by the MATLAB-based software-defined GPS receiver.It will spoof the GPS receiver clock offset in the PMU.The maximum positioning error of the receiver is about 35 meters.When the amplitude of the interference signal is increased to a certain degree,the receiver can only search for the interference signal.Then the principle of GPS timing is studied.The GPS clock and the receiver clock are calculated,and the GPS timing error is analysised.The simulation of GPS retransmited jamming is used to calculate the receiver clock,the maximum deviation can reach 107?s.Focus on the influence of the accuracy of the PMU of substation,the PMU of power plants as well as the fault location.The receiver clock error will result in the deviation of measurement of PMU and the fault location.The error of measurement of PMU is close to 2 degrees,the error of fault location is about 16 km.