Electric Power ›› 2022, Vol. 55 ›› Issue (2): 152-158.DOI: 10.11930/j.issn.1004-9649.202111041

• Renewable Energy Consumption • Previous Articles     Next Articles

LVRT Reactive Current Index of Renewable Units Based on the Constraints of Transient Voltage

LIU Hui1, WANG Kuo2   

  1. 1. State Grid Jibei Electric Power Research Institute, Beijing 100045, China;
    2. Peking University, Beijing 100191, China
  • Received:2021-11-09 Revised:2022-01-22 Online:2022-02-28 Published:2022-02-23
  • Supported by:
    This work is supported by Science and Technology Project of SGCC (No.52018K21N00H).

Abstract: The renewable power gathering system often presents the characteristics of a weak AC grid. And the voltage fluctuates greatly during the failure process. The problem of renewable units being turned-off due to low voltage and transient overvoltage is prominent. This paper establishes the voltage-current relationship of the renewable power gathering system. Considering the safety constraints of low voltage and transient overvoltage, we gives the LVRT reactive current index requirements for the renewable units through theoretical derivation. Then, the renewable power gathering system is classified according to the short circuit ratio (SCR), and for systems with different SCRs, differentiated LVRT reactive current index requirements are given.

Key words: renewable power gathering system, low voltage ride through, transient overvoltage, short-circuit ratio