交直交机车谐波特性及其诱发过电压的治理

Harmonics Characteristic of AC-DC-AC Locomotive and the Disposal of Resonance Overvoltage

针对现代铁路大量采用交直交电力机车后,在牵引供电系统中频繁出现的设备绝缘击穿、避雷器爆炸、变电所跳闸、牵引网接触线烧损等问题,利用电磁暂态仿真软件PSCAD/EMTDC建立分布参数的牵引网模型和变流器-电机联合控制的电力机车模型,研究分析牵引网长度、机车位置与不同谐波阻抗测量点阻频特性的关系;牵引功率和牵引网电压对交直交电力机车谐波特性的影响。基于以上两点总结谐振过电压的分布特点,利用GA算法优化高通滤波器的参数并仿真分析不同安装位置时的谐波电压分布情况,得出在变电所出线安装可使电压畸变率降为0.35%,满足公用电网电能质量3%的指标,且有充足的安全裕量。

To address problems in traction power supply system such as equipment insulation puncture,explosion of lightning arresters,trip of traction substation and eroding of contact line,which arise out of the wide use of the AC-DC-AC locomotive in modern railway system,the electromagnetic transient simulation software PSCAD/EMTDC was used to establish the simulation model of traction network with distributing parameters and electric locomotive model with joint control of current transformer-electric motor,to analyze the relations between the length of traction line,locomotive position and the impedance characteristics of different harmonic impedance measurement points and the influence of traction power and voltage on the harmonic characteristic of AC-DC-AC locomotive.Based on the above,the distribution characteristics of resonant overvoltage were summarized.The optimization of the parameters of a high pass filter by GA algorithm and the simulation of the distribution of harmonic voltage at different installation positions concluded that the installation of the high pass filter at the substation outlet can reduce the voltage distortion rate to 0.35%,which meets the 3% distortion rate for the power quality of the public grid,and has sufficient safety margin.