Research On Single-ended Traveling Wave Ranging Method For 110kV T-connection Transmission Line

Nowadays,the development of the national economy is increasingly dependent on electric energy,the demand for electricity is increasing,and the power network is becoming more larger.The rapid development of the power grid has led to tight resources in the corridors.The application of the T-type transmission line has reduced the occupation of corridor resources to a certain extent.At the same time,when the T-type transmission line is different from the traditional double-ended transmission line,when the T-type transmission line fails,the fault location of the single-ended traveling wave method needs to be studied.After a fault occurs in the T-type transmission line,this paper analyzes the fault traveling wave after the fault through six conditions.The fault traveling wave propagates in the line and is deflected at multiple points.After the first end of the fault point is measured at the measuring end,it is difficult to identify the subsequent wave head,which makes it difficult to achieve single-ended fault location of the T-type transmission line.In this paper,n-division singular value decoposition is used to detect the singular value of the fault traveling wave.The two-division singular value decoposition is improved.The improved n-division recursion singular value decoposition has a certain inhibitory effect on the burrs in the waveform.According to the characteristics of the T-connected line structure,the deflection reflection of the traveling wave in the line after the failure of the T-connected line is analyzed,and a method for single-ended ranging of the T-type transmission line is proposed.The 110 kV T-type transmission line model is established by PSCAD/EMTDC simulation software,and different fault types in different sections of the T-type transmission lines are simulated respectively.The full-line matching method proposed in this paper is tested.The simulation result is the full-line matching algorithm used in this paper.Verification is carried out and the verification results are accurate and reliable.This paper introduces the 110 kV non-contact traveling wave acquisition and analysis device,and verifies the 110 kV non-contact traveling wave acquisition and analysis device by using Real Time Digital Simulator(RTDS).After the verification is completed,it is installed at the production site of a 110 kV substation in Yunnan province,and the fault waveform of the 110 kV T-type transmission line is collected from the production site.The full-line matching method adopted in this paper is calculated by the measured fault waveform.The calculation results show that the full-line matching algorithm can realize the single-ended fault location of the T-type transmission line.