| With the continuous development of cross-region power grid,Extra-high voltage converter station and Ultra-high voltage converter station play an increasingly important role in the power grid.Once there occurs anomaly and fault block in the converter station of high-voltage direct current transmission system,it will bring certain disturbance and impact to the power grid at both the receiving end and the sending end.More than that,it will threaten the safe and stable operation of the system.Currently,the Wave Analysis Software used in converter station is generally developed for AC substation.But due to the particularity of converter station,equipment failure in different regions has its own characteristics.Moreover,there exit a big difference between HVDC core equipment and AC equipment in the field of failure form and mechanism.All of these lead to the fact that the Wave Analysis Software now cannot be used to analysis faults of HVDC system and it can only used to check the fault wave record chart.Considering the importance of HVDC transmission system,Timely analysis and processing is particularly important after failure.So,it is quite necessary to design a Fault Recording and Analysis Software of HVDC transmission system in order to improve the accuracy,convenience and timeliness of the data analysis of HVDC fault recorder.Due to the shortcomings of the present DC fault recording system,a Wave Analysis Software of HVDC System based on COMTRADE data format is designed by the MATLAB simulation software in this paper.This software can not only realize the function of the call and check of the fault record file,but also be used by the on-site technical personnel to compare and analyze the fault data recorded by different fault recorders.The analysis software compiled by MATLAB language use windows to display and has a friendly interface andsimple operation advantage.In addition,in order to facilitate the failure analysis,the software can also store,view and analysis historical data.For HVDC transmission project,the commutation failure and the overvoltage of the DC neutral line are the two most typical failure modes.This paper analyzes the principle and process of these two kinds of HVDC system fault,and puts forward a method of automatic analysis of commutation failure by using fault recorder data;The corresponding overvoltage prediction function is designed in this paper for the overvoltage fault of the DC neutral line.Compared with the existing HVDC fault recording and analysis software,the analysis software designed in this paper combines the failure mode and mechanism of the HVDC core equipment,expands the new analysis function of the HVDC fault recording system,and has a broad prospect of application. |
