Abstract: In order to solve the problem that the centralized controller cannot quickly and flexibly allocate power to power conversion system（PCS） due to the increasing number of PCS in battery energy storage system, a distributed power allocation strategy based on consistency algorithm is proposed in this paper. The strategy takes into account the state of charge balance and operation efficiency of each battery unit, iteratively calculates the power instruction value of each battery unit according to the consistency algorithm, and takes the absolute error of the power instruction in the iteration of adjacent units as the convergence criterion to determine the end of the iteration, so as to realize the power allocation of each PCS to meet the specific requirements in different scenarios. Finally, the cycle life loss, capacity reserve and energy loss of the proposed strategy are compared with the existing power allocation strategies, and the effectiveness of the proposed strategy in the peak load balancing scenario is verified by simulation.