大型风电场接入对交直流并行输电系统频率影响研究

摘要

This paper investigates the output conditions of delivering large-scale wind-thermal combined generation by AC-DC parallel transmission systems , a two-area system with four generators , large-scale wind farms and HVDC line between area 1 and area 2 was built up in PSCAD/EMTDC.Simulations were carried out under the circumstances of using wind energy to replace thermal power , and the results showed that the capability of frequency control of the ther-mal power units were better than that of wind generators .Finally, automatic generation control ( AGC) was added to generator 2 in area 1, the AGC was designed taking into account both the AC line power changes and the DC transmis-sion line power changes , and the frequency characteristics of the system and its stability were improved .%针对风火打捆经交直流并行输电系统送出的情况，搭建了含交直流并行输电线路的四机两区模型以及大型风电场模型，将大型风电场加入到四机两区模型当中。通过仿真对用风电代替火电时系统受到扰动时频率变化进行对比，得出风电机组的接入会使得系统的频率特性变差。并在系统中加入同时考虑交流线路和直流线路传输功率变化的自动发电控制（ AGC），仿真结果表明，所设计的AGC能够有效的改善系统的频率特性，提高系统的稳定性。