基于改进的稳态法获取三相系统谐波阻抗  

The three-phase system harmonic impedance determination based on the improved steady-state methods

作　　者：艾永乐[1] 都静静[1] 王玉栋[1] 王伟[1] 

机构地区：[1]河南理工大学电气工程与自动化学院,焦作454000

出　　处：《电子测量技术》2015年第12期15-19,25,共6页Electronic Measurement Technology

基　　金：河南省控制工程重点学科开放实验室资助项目(KG2011-06)

摘　　要：在三相电力系统,当各相间存在耦合阻抗以及三相系统不对称运行时,应用稳态法和瞬态法不能获取准确的谐波阻抗,本文提出改进的稳态法来获取系统侧谐波阻抗。首先求取相模变换矩阵,将三组可测数据解耦成单变量数据,简化计算过程;其次,在MATLAB/Simulink中建立单相仿真模型,对稳态法和瞬态法进行对比;第三,建立存在耦合阻抗且不对称运行的三相仿真模型,应用稳态法与改进的稳态法计算系统侧谐波阻抗。实验表明稳态法比瞬态法获取阻抗值更加准确,且受干扰因素较少;选择稳态法获取系统侧谐波阻抗,经相模变换改进后,提高了准确率,并简化了计算过程。Steady-state methods and transient methods can＇t give the accurate results when the coupling impedance and three-phase unbalance load exist in power system.In this paper,the improved steady-state method is proposed to obtain the system harmonic impedance.Firstly,the phase-mode transformation matrix is calculated which can de-couple the three measurements into a set of single variables and simplify the calculation process;Secondly,single-phase model is established by MATLAB/Simulink to compare steady-state methods with transient methods;Thirdly,three-phase model is established which exists the coupling impedance and three-phase unbalance load.The steady-state methods and the improved steady-state methods is applied to calculate the the system harmonic impedance.The results show that the steady-state methods is more accurate than the transient methods and have less interference;The steady-state methods is improved by the phase-mode transformation and the improved methods is selected to obtain the system harmonic impedance which improves the accuracy and simplifies the process of calculation.

关 键 词：系统侧谐波阻抗 改进的稳态法 相模变换 稳态法 瞬态法 

分 类 号：TM74[电气工程—电力系统及自动化]