With the increasing complexity of networked power systems, traditional control schemes are difficult to meet the actual needs. Bandwidth constraints, network security and actuator saturation have become important factors affecting the stability of power systems. An improved event trigger mechanism was introduced to improve the utilization rate of bandwidth resources for the problem of bandwidth resource limitation, and a new mathematical model of power system under deception attack and actuator saturation was constructed. Based on this number model, the sufficient conditions for the asymptotic stability of the power system were obtained by Lyapunov theory, and the design scheme of the security controller was given by using linear matrix inequality technique. Finally, an example of power system was given to illustrate the effectiveness of the proposed scheme.