BESS Adaptive Reclosing Method using Second-Order Difference of THD in Distribution System with BESS used as Uninterruptible Power Supply

摘要

The present invention relates to an adaptive reclosing method of a battery energy storage system (BESS) associated power distribution system. More specifically, the adaptive reclosing method of the BESS associated power distribution system comprises the following steps of: receiving a current (i_1(t)) and a voltage (V_1(t)) from a system and receiving a current (i_2(t)) and a voltage (V_2(t)) from the BESS; calculating an effective value of i_1(t) and total harmonic distortion (THD) of i_2(t); checking whether malfunction occurs by checking whether the relation of I_(1RMS_A) or I_(1RMS_B) or I_(1RMS_C) α is satisfied; detecting a fault phase; checking whether the relation of I_(2THD)[i] - I_(1THD)[i] β is satisfied in the fault phase; performing moving data window processing and returning to the fault phase detecting step if the relation of I_(2THD)[i] - I_(1THD)[i] β is not satisfied; checking whether a duration threshold reaches ε or more; checking whether a synchronization inspecting condition is satisfied by using a voltage, a phase angle and a frequency of the BESS; and transferring a closing operation command to a reclosing machine if the synchronization inspecting condition is satisfied. Therefore, the adaptive reclosing method of the BESS associated power distribution system can provide an adaptive reclosing technology having high reliability.