With the continuous expansion of the grid-connected scale of wind farms, the problem of the stability of the grid-connected point voltage of wind farm cluster has become increasingly prominent. However, the current reactive voltage control strategy of wind farm cluster has less research on the optimization of the internal node voltage and grid loss of wind farms, and the problem of the reduction of wind turbine life caused by the full reactive power of doubly-fed wind turbines needs further research. In view of the above problems, this paper proposes a wind farm cluster reactive voltage hierarchical control strategy based on the reactive power margin of doubly-fed wind turbines. The strategy improves the traditional artificial fish algorithm and realizes the reactive voltage control of wind farm cluster. As a result, the node and network loss have reached a certain degree of optimization.