Monitoring System For Power Transmission Line Galloping Based On MARG Sensor

The galloping of power transmission line(PTL)is one of potential threats in the operation of smart grid,for it can easily cause huge tragedy.This phenomena happens when the PTL is inspired by strong wind under heavy weather.It's a kind of low-frequency,long-duration and large-amplitude movement of PTL.It can evoke the terrible accident of inter-phase shortcutting,damage to supporting surctures,cause short-circuiting,burn conductor and hold down tower.The recent researches on PTL galloping are focused on galloping mechanism,galloping monitoring and anti-galloping.Real-time monitoring system for PTL galloping is capble of sending warning signal in time when PTL start galloping,in addition,providing first-hand material for the study of galloping mechanism,galloping pattern and galloping preventing.So,it has a huge amount of value.The mainstream monitoring technology is based on vidio surveillance and sensor supervision.The monitoring systems based on accelerometers use three-axis accelerometer and calculate displacement of measuring point by double integrating the acceleration.However,this paper illustrates the mistakes existing in these systems through theoretical and exprimental analysis.For the sensors depolyed on PTL may rotate around the PTL's axis during galloping,it will cause the mistake of acceleration.So the measuring data by accelerometers can not reflect the true movement when the PTL twist during galloping.To cure the above problems,this paper presents two monitoring algorithm structure using Magnetic angular rate and gravity sensor(MARG),also named as 9-axis sensor.The MARG contains three-axis accelerometer,three-axis magnetometer and three-axis gyroscope.Using MARG,one can not only overcome the acceleration mistake caused by rotation,but also rebuild the whole PTL curve in real time by multiple MARGs.Firstly,this paper proposes the 9-axis PTL galloping monitoring algorithm using one MARG(Single MARG monitoring algorithm)and evaluates the effect of it through simulations and expriments.It is proved that the recovered displacement by single MARG monitoring algorithm is much more accurate than the tradition algorithm.Secondly,in order to rebuild the whole PTL galloping curve,this paper proposes the 9-axis PTL galloping monitoring algorithm using multiple MARGs(multi-MARG monitoring algorithm),including the sub algorithm: Attitude-Curve recovery algorithm(AC recovery algorithm).AC recovery algorithm gives up the principle of acceleration integration,and improves the recovery precision.Similarily,this paper compares the recovery effect of two 9-axis monitoring algorithm through simulations,and prove the high accuracy of the second one.