UHVDC 分层接入方式下非故障层换相失败改进抑制措施研究

作者：Li Shenghu^*; Li Yikai; Tao Diwen; Liu Yushun; Yang Wei; Wu Zhengyang

来源：Power System Technology, 2022, 46(11): 4502-4511.

DOI：10.13335/j.1000-3673.pst.2021.2503

• commutation failure suppression
• DC current prediction
• firing angle correction
• HCM
• UHVDC transmission
• VDCOL

The ultra high-voltage DC (UHVDC) under the hierarchical connection mode (HCM) has coupling between the inverter sides. So the dominant factors and suppression measures of commutation failures are more complex than those of the common UHVDC. First, considering the transient characteristics of the DC current after an AC fault, the commutation area to be compensated at the fault and non-fault layers is proposed. The relationship between the firing angle reference and the compensated commutation area is derived to modify the firing angle reference at the inverter side for the advanced firing control. Then the start voltage of the voltage dependent current order limiter (VDCOL) is changed with the modified firing angle reference to improve the response speed and help the advanced firing angle control. Finally, the simulation model with the PSCAD/EMTDC is built. It is validated that the proposed control method reduces the risk of commutation failures of the non-fault layer and improves the fault recovery performance. ? 2022 Power System Technology Press.

• 单位
  合肥工业大学