高压直流输电系统中双调谐滤波器参数研究及其仿真

针对高压直流系统中的换流装置产生谐波的问题,在高压直流输电(HVDC)系统中宜采用双调谐滤波器。对双调谐滤波器的特性进行分析和参数设计:由基波无功补偿容量公式推算出串联回路电容;由谐振频率与参数的关系确定串、并联电感及并联电容。由滤波参数可得出谐振点的公式,通过理论重点分析了双调谐滤波器在调谐频率下略显感性的重要意义,同时引入安全系数。最后,通过对一计算实例进行参数计算,并运用Matlab/Simulink对其仿真。结果表明,考虑到系统频率偏移,防止与系统发生并联谐振等综合因素,安全系数取1.0～1.1时效果较佳。

Study on parameters of double tuned filter in HVDC transmission system and its simulation

It is recommended to use the double tuned filter in HVDC(High Voltage DC transmission)systems to suppress harmonic currents produced in conversion equipments.Its characters are discussed and its parameter design is presented:the series loop capacity can be deduced by solving the fundamental wave reactive compensation formula;the series,shunt inductance and the shunt capacity can be determined by the relationship of the resonance frequency and parameters.Formulas for calculating resonance points from filter parameters are deduced,and the significance of filter's being slightly inductive at tuned frequency is emphasized.At the same time,a safety coefficient is introduced.An example of filter parameter calculation is given and also simulated with Matlab / Simulink.Results show that,considering the system frequency deviation and avoiding its shunt resonant with the system,the safety coefficient is selected from 1.0 to 1.1 to obtain the better filtering effect.