一种新型的高压直流输电系统交流侧谐波电压测量方法

A Novel AC Side Harmonic Voltage Measurement Scheme of High-voltage DC Power Systems

准确有效地进行高压直流输电系统交流侧谐波电压测量是掌握直流输电系统实时运行状况,研究分析交流滤波器设计正确性、有效性的重要前提和依据,该文提出一种新颖的高压直流输电系统交流侧谐波电压的测量方法,以解决目前缺乏高性价比高压谐波电压测量手段的问题。该方法测量流过交流侧滤波器各支路的电流,根据对电流的谐波分析结果,结合滤波器的元件参数或已知的阻抗?频率特性,即可简单方便地计算得到交流侧的谐波电压。该方法仅需在传统交流滤波器的基础上进行简单改造即可实现,测量电压谐波精度高,扩展了交流滤波器的功能。给出该方案的原理和谐波电压的计算方法,对利用不同滤波器进行谐波电压测量的性能进行比较,研究滤波器参数变化和电流传感器测量精度对谐波电压测量结果的影响。通过仿真计算验证所提出方法的正确性和有效性。

Accurate and effective measurement of the AC side harmonic voltage of HVDC transmission systems is an important basis for the research and analysis of the correctness and validity of the design and operation of AC filters, and is also the premise to master the real-time harmonic condition of HVDC systems. A novel method that can solve the problem of lacking of high cost-effective harmonic voltage measurement means in HVDC systems was proposed in this paper. The principle of this method is to measure the current of the AC filter of HVDC power systems, and the harmonic voltage on the AC side can be calculated conveniently according to the harmonic analysis results of the measured current and the component parameters or known impendence-frequency characteristics of the filter. This method can be performed on the basis of traditional AC filters with simple modification and can achieve high accuracy harmonic voltage measurement, thus expands the functions of the AC filter. The principle of the proposed method and the harmonic voltage calculation method were presented, the performances of harmonic voltage measurement utilizing different filters were compared, and influences of the changes of AC filter parameters and the measurement accuracy of the current transformer on the measurement of harmonic voltage were researched. The correctness and effectiveness of the proposed method were verified by simulations.