Electric Power ›› 2022, Vol. 55 ›› Issue (8): 157-164.DOI: 10.11930/j.issn.1004-9649.202101039

• Power System • Previous Articles     Next Articles

Safe Operation Area of Energy-Storage-Free Dynamic Voltage Restorer

ZHU Mingxing1, LU Xuan1, ZHANG Huaying2, WANG Qing2   

  1. 1. School of Electrical Engineering and Automation, Anhui University, Hefei 230601, China;
    2. New Smart City High-Quality Power Supply Joint Laboratory of China Southern Power Grid Shenzhen Power Supply Co., Ltd., Shenzhen 518020, China
  • Received:2021-01-08 Revised:2022-02-20 Published:2022-08-18
  • Supported by:
    This work is supported by Science and Technology Project of China Southern Power Grid (No.090000KK52190169, No.SZKJXM2019669).

Abstract: Energy-storage-free dynamic voltage restorer (DVR) is a common device used to solve voltage sag problems in engineering, but its actual operation is limited by the parameters of application scenarios. To solve this problem, an algorithm is proposed for the safe operation area of energy-storage-free DVR, which can calculate the maximum compensation capacity of energy-storage-free DVR based on the application scenario parameters, thus standardizing the application of energy-storage-free DVR in engineering. Firstly an impedance model of the system is built based on the relationship between the cable, transformer and the safety compensation range of the energy-storage-free DVR device. Secondly, the secondary voltage sag caused by the compensation process of the energy-storage-free DVR is analyzed, and the safe operation area of the energy-storage-free DVR device is calculated based on the overload capacity of the system. Finally, the calculation method of the safe operation area is further clarified by simulation analysis. The proposed calculation method determines the safe operation area of the new energy-storage-free DVR under the constraint conditions of the application scenarios, which provides a theoretical reference for the effective application of the energy-storage-free DVR.

Key words: energy-storage-free dynamic voltage restorer, application scenarios, secondary voltage sag, compensation capacity, safe operation area