In this paper, set theory is introduced to the design of authenticated key agreement scheme for heterogeneous sensor networks, and a scheme based on bilinear dynamic accumulator is proposed. The previous schemes based on classical random graph and others mainly achieve key agreement between nodes, and separate authentication and key agreement. From the perspective of set theory, this work transforms authenticated key agreement into set element relationship certification, and integrates identity authentication and key agreement. It includes identity authentication, key agreement, and broadcast authentication. Sensors verify the identity of each other by exchanging ID and witnesses. Legitimate nodes generate a shared key. Broadcast messages are used to dynamically add/delete nodes, and update witness. Experimental results show that the new scheme not only achieves effective integration of authentication, key agreement and broadcast certification; but also has better security, scalability, and adaptive changes in the network structure. It is suitable for higher node performance and security requirements scenarios.