In order to describe the hybrid characteristics of the discrete cyber system and the continuous physical system, a novel CPS architecture is proposed based on hybrid automata model, Multi-Agent System (MAS) and spatial-temporal event driven mechanism. The main body of our CPS architecture is constructed based on improved hybrid automata theory. Meanwhile, by defining spatial-temporal event-based CPS event, designing the MAS-based CPS client architecture, and using the defined CPS clients with different functions and CPS event driven mechanism, the inherent cyber physical interaction and feedback process of the CPS architecture is analyzed. Finally, taking the vehicular velocity regulation and control system for instance, the inherent cyber-physical fusion process of vehicular velocity regulation and control in cooperative driving system is analyzed and formalized with our proposed CPS architecture, and the formalization process demonstrates the effectiveness of our proposed CPS architecture. The proposed CPS architecture provides novel thoughts and methods for describing the inherent characteristics of CPS.