谐波对变压器的影响及其抑制措施分析

随着电力系统的迅速发展和新型电气设备的应用,电力系统的谐波问题日趋严重。产生谐波的根本原因是由于给具有非线性阻抗特性的电气设备供电的结果。谐波的危害十分广泛,主要有:干扰通信线路的正常工作;引起电机和变压器等电气设备的热损耗增加,效率下降,绝缘老化,缩短设备寿命;使电网无功功率增加,功率因数下降,甚至引发串联或并联谐振,损坏电气设备。抑制谐波的措施:一是增加换流装置的相数;二是采用被动防御的无源滤波法和主动预防的有源滤波法。

Effects of Harmonics on Transformer and Its Suppression Measures

As the fast development of power system and application of new electric equipment,harmonic problems are becoming more and more severe.The fundamental cause of harmonics is due to power supply to electric equipment with nonlinear impedance characters.The harm of harmonics is broad,mainly including: interfering normal operation of communication lines;increasing heat loss,reducing efficiency,causing insulation aging,and reducing life of electric equipment like motor and transformer;increasing grid reactive power,reducing power factor,or even damaging equipment by inducing series or parallel resonances.Harmonic suppression measures include:(1) increasing phase number of converter device,(2) using defensive passive filters and offensive active filters.