摘要
针对宁东高压直流输电工程换流站模拟试验出现的电流采样的波动问题,研究了高压直流输电系统在整流和逆变过程中,存在23次和25次谐波与基波频率混叠现象,可能对保护性能产生影响。运用MATALB仿真软件分析了频率混叠的产生机理,然后提出了提高采样频率和加装硬件滤波回路的改进措施,以提高交流滤波器保护的可靠性。
HVDC transmission system in rectifying and inverter process produces a large number of harmonics, for 12 pulse converter, the ac side can produce 11, 13, 23, 25... times features harmonic. In ac filter base wave protection calculation using 24 points / cycle sampling limitations, can cause harmonic frequency aliasing , 23 and 25 times harmonic will be also taken into fundamental wave, which causes base wave protection calculation error, to effect the correctness of fundamental wave protection action. Therefore, the author analyzed the generating mechanism of frequency aliasing through MATALB simulation software, and then puts forward enhancing sampling frequency and adding hardware filter circuits solutions for the experts and readers reference.
出处
《电力科学与工程》
2011年第11期49-52,共4页
Electric Power Science and Engineering
关键词
交流滤波器
采样
频率混叠
基波保护
AC filter
sampling
frequency aliasing
fundamental wave protection
