摘要
电力系统谐波阻抗随电流幅值变化出现电力波动特性干扰,导致估算精度下降。提出基于线性度校验的电力系统谐波阻抗估计方法。分析电流幅值随时间的正弦波动值、线性波动值与随机波动,获取电力波动特性对谐波阻抗估计的电力波动特性干扰因素,收集谐波阻抗数据,构建系统谐波阻抗估计的极大似然模型,获取谐波阻抗的元复正态线性度变量独立分布采样,计算线性度变量服从几率密度函数值,组建极大似然估计函数,估算谐波阻抗的极大似然模型,得到电力系统的谐波阻抗估计值。仿真结果证明,估算精度与稳定性得到提高。
The power fluctuation characteristics of the harmonic impedance of the power system lead to low estimation accuracy.Therefore,this paper reported a method of harmonic impedance estimation based on linearity check.Firstly,the sinusoidal,linear and random fluctuations of current amplitude with time were analyzed in detail to obtain the interference factors of power fluctuation characteristics on harmonic impedance estimation.Secondly,the harmonic impedance data was adopted to construct the maximum likelihood model of harmonic impedance estimation,thus obtaining the independent distribution sampling of the element complex normal linearity variable of harmonic impedance.Then,the linear variable obeys the probability density function value,being calculated to construct the maximum likelihood estimation function.Meanwhile,the maximum likelihood model of harmonic impedance was assessed.Finally,the estimated value of the harmonic impedance for the power system was obtained.The simulation results show that the method can improve the estimation accuracy and stability.
作者
马思棋
王忠
MA Si-qi;WANG Zhong(School of Electrical Engineering,Sichuan University,Chengdu Sichuan 610065,China)
出处
《计算机仿真》
北大核心
2022年第11期96-99,188,共5页
Computer Simulation
基金
四川大学重大科研项目(17H0366)
四川省教育厅2018自然科学重点科研项目(18ZA0307,18ZA0308)。
关键词
线性度
电力系统
谐波阻抗
几率密度函数
电力波动特性
Linearity
Power system
Harmonic impedance
Probability density function
Power fluctuation characteristics
