摘要
为了改善多馈入直流输电(MIDC)系统的故障后的恢复性能,在研究低压限流单元(VDCOL)对直流系统电压稳定性影响的基础之上,提出了一种基于广域测量系统(WAMS)的多馈入直流低压限流单元的协调控制方法。首先利用灵敏度分析法,研究了直流功率对交直流系统电压稳定性的影响;然后设计了一种基于广域测量系统的多馈入直流低压限流单元的协调控制方法,该方法根据相量测量单元的测量结果,评估故障对各直流输电子系统的影响,并调整和控制故障点附近各直流子系统VDCOL的输出,从而改善多馈入直流输电系统的动态性能;最后对该协调控制方法进行了仿真验证。从仿真结果可以看出,所提出的基于广域测量系统的多馈入直流低压限流单元的协调控制方法能够有效避免系统发生连续的换相失败故障,提高系统的电压稳定性,从而改善系统的恢复性能。
In order to improve the performances of failure recovery characteristic of the MIDC,we proposed a novel control method for coordinated VDCOLs after studying the influence of VDCOL on the voltage stability of HVDC system. Firstly, a sensitivity analysis method is used to study the effect of DC on AC/DC power system voltage stability; secondly, a control method for coordinated VDCOLs is designed based on the WAMS. According to the measurement resuits of phasor measurement unit, the effect of fault on the DC transmission subsystem is assessed, and it can adjust and control the output of the HVDC subsystems＇ VDCOL near by the fault point in order to improve the dynamic performance of MIDC system. Finally, a simulation is performed to verify the coordinated control method. From the simulation results, it can be verified that the coordinated control method of the VDCOLs based on the wide-area measurement system can avoid the continuous commutation failure and improve the voltage stability of the system, and thereby improve the recovery performance of the whole system.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2017年第4期1168-1174,共7页
High Voltage Engineering
基金
国家重点基础研究发展计划(973计划)(2013CB228200)
国家电网公司科技项目(522830140003)~~
