To address issues such as communication topology symbolization, path directionality and external interference that cause a decline in speed coordination control accuracy in multi-motor systems such as unmanned aerial vehicle formations and industrial robotic arms, this paper proposes a speed coordination control strategy for multiple permanent magnet synchronous motors based on bipartite consensus. First, each single motor control system is considered an intelligent body, and the multi-permanent magnet synchronous motor speed cooperative control problem is transformed into a bipartite consensus problem containing a virtual navigator. The distributed control protocol is designed based on the principles of dividing by competitive relationships, directly participating in weight shares, and summation adjustment by in-degree weights. Second, a sliding mode speed loop controller based on an improved variable power reaching law is designed for the permanent magnet synchronous motors. Simultaneously, an ultra-local model-based design of model-free sliding-mode controllers for the current loops of the leader motor and each of the follower motors is used to improve the control accuracy and anti-interference capability of the multi-motor system. Finally, the proposed method is validated by constructing a simulation platform for five permanent magnet synchronous motors. Under no-load condition, it can realize high-precision speed tracking within a finite time, and the steady state tracking error is lower than 0.006%; under load disturbance, it can effectively inhibit both homogeneous and heterogeneous load disturbance conditions. When connectivity decreases due to communication topology switching, the overall convergence time and steady-state tracking error remain stable despite a slight increase in collaborative error. This method provides an effective solution for the high-precision and robust speed cooperative control of multiple permanent magnet synchronous motors under complex communication topologies.