适用于数字化保护的改进递推傅里叶算法  

An Improved Recursive Fourier Algorithm for Numerical Relays

作　　者：刘益青[1] 高伟聪 孙天德 

机构地区：[1]济南大学自动化与电气工程学院,山东省济南市250022 [2]山东外事翻译职业学院,山东省济南市250100 [3]积成电子股份有限公司,山东省济南市250100

出　　处：《电网技术》2016年第5期1601-1606,共6页Power System Technology

基　　金：山东省自然科学基金项目(ZR2014EEM039)~~

摘　　要：傅里叶算法的非递推形式计算量大,限制了其在数字化保护中应用;递推形式虽然计算量大幅减小,但有限字长效应引起的误差和计算过程中的截短误差都会在递推过程中产生累积,严重影响计算精度和长期运行稳定性。在分析递推形式累积误差来源及特点的基础上,研究了一种递推形式与非递推形式交替计算的改进递推傅里叶算法,以达到尽量减小累积误差的目的。同时,采用加权乘积项分布、同步计算技术,使改进算法的计算量比持续递推算法仅增加2次加法,保持了递推算法的固有优点。改进算法已经应用于智能站母线保护和站域保护等需要接入大量模拟量装置的开发,数字仿真结果和样机长期运行测试结果表明改进算法有效减小了累积误差影响,相比非递推计算形式,计算量大幅降低。Computation burden of non-recursive Fourier algorithm is well-known heavy,limiting its application in numerical relays.Although recursive form of Fourier algorithm reduces computation burden greatly,errors caused by finite word-length effect and truncated data bits seriously affect accuracy and long-term stable operation because the errors will be cumulated step by step.Based on sources and characteristic analysis of cumulative errors mentioned above,the paper proposes an improved method calculating alternatively using recursive and non-recursive forms to minimize cumulative errors.Moreover,employing distribution and synchronous calculation technology for weighted product terms,the improved method maintains inherent advantages of recursive algorithm,whose calculation amount only increases 2 additions compared with continuous recursive algorithm.The proposed method is applied in busbar protection and substation-area protection for smart substation requiring access of large number of analog channels.Digital simulation and prototype long-term running experiments show that the improved method can effectively reduce cumulative errors and drastically decrease computation burden in comparison to non-recursive algorithm.

关 键 词：傅里叶算法 递推算法 累积误差 

分 类 号：TM77[电气工程—电力系统及自动化]