ABSTRACT Affected by the different fault characteristics of electrochemical energy storage power stations under charging and discharging operating states, the phase comparison distance protection using positive sequence voltage as polarisation voltage may operate incorrectly if phase‐to‐phase faults occur in the forward direction of the energy storage side protection and the reverse direction of the system side protection. Therefore, an improved distance protection scheme for phase‐to‐phase faults that can adapt to both charging and discharging states is studied. Firstly, the fault characteristics of the energy storage station under different charging or discharging states are analysed, and the influence mechanism of fault characteristics on phase comparison distance protection operation performance is discussed. On this basis, an improved distance protection scheme for phase‐to‐phase fault based on polarisation voltage phase reconstruction was proposed. Finally, verification was conducted on the PSCAD/EMTDC simulation platform. The simulation results show that the proposed scheme can effectively reduce the impact of fault characteristics of energy storage power stations. The sensitivity and reliability of phase comparison distance protection during phase‐to‐phase fault are effectively improved under different charging and discharging states and fault resistance conditions.
Zhu et al. (Thu,) studied this question.