一种适用于特高压直流分层接入系统的换相失败抑制策略
摘要：特高压直流分层接入系统中，当逆变侧交流系统故障时，由于非故障层换相失败预防控制的启动时刻存在延迟，可能导致高低端换流器同时发生换相失败。为此，提出一种基于换相时间电压积分面积的高低端换流器协调控制策略。利用故障层换相失败预防控制可更快速对故障作出反应的特点，所提策略将故障层换相失败预防控制的输出量引入非故障层，使非故障层换相失败预防控制的启动时刻提前，增大非故障层换流器的关断角；同时对低压限流控制环节进行改造，减小故障过程中的直流电流。在PSCAD/EMTDC中搭建仿真模型对不同工况下所提策略进行验证。结果表明，该策略可显著提高非故障层换流器对故障的灵敏度，减小同时发生换相失败的风险。
Abstract:In the UHVDC Hierarchical connection system, when the AC system on the inverter side fails, the commutation failure of the high and low end converters may occur at the same time due to the delay in starting the commutation failure prevention control of the non-faulty layer. Therefore, a coordinated control strategy of high and low side converters based on the commutation time and voltage integral area is proposed. Taking advantage of the fact that the commutation failure prevention control of the faulty layer can respond to faults more quickly, the proposed strategy introduces the output of the commutation failure prevention control of the faulty layer into the non-faulty layer, so that the start time of the commutation failure prevention control of the non-faulty layer is advanced, increase the turn-off angle of the non-faulty layer converter; at the same time, the voltage dependent current order limiter control is modified to reduce the DC current during the fault process. A simulation model was built in PSCAD/EMTDC to verify the proposed strategy under different working conditions. The results show that this strategy can significantly improve the sensitivity of non-faulty layer converters to faults and reduce the risk of simultaneous commutation failures.
标题：一种适用于特高压直流分层接入系统的换相失败抑制策略
英文标题：A Commutation Failure Suppression Strategy for UHVDC Hierarchical Connection Systems
作者：晁武杰, 林国栋, 戴立宇, 李元琦, 王渝红, 陈立维,
关键词：特高压分层接入系统, 换相失败, 电压时间积分面积, 换相失败预防控制, 低压限流控制,
发表日期：2023-12-04
- 文件大小:
- 3.25 MB
- 下载次数:
- 60
-
高速下载
|
|
