###### Abstract
performed modeling on the whole satellite system and studied the effects of the coupling of the dynamics subsystem, attitude control subsystem, propulsion subsystem and energy subsystem on the change in satellite status [10]. The mainstream software used in the construction of the constellation system model includes FreeFlyer, STK and Savi, which allow the computation and visualization of the orbit, motion and ground coverage of the satellite to simulate constellation orbits and space environments [11]. In 2021, [PERSON] [12] used STK software to model a constellation of GPS M-code satellites. Through simulation, the visible number of satellites and the distribution of the geometric accuracy factors of the constellation in different regions of the world are obtained, and the constellation is verified to be able to provide stable and reliable communication services around the world. The communication link system model mainly consists of network simulation software suitable for constellation simulation environments, such as OPNET Modeler, ns-3, etc., which adopts discrete event simulation technology and provides a variety of network protocols and functions to simulate the communication processes, such as satellite paging, chain building and link switching, during high-speed motion and to evaluate the communication quality. In 2018, [PERSON] built a low-orbit satellite constellation mobile communication system simulation platform based on OPNET which can correctly simulate the main communication processes of LEO communication systems and the characteristics of satellite communication such as long-time delay and frequent switching [13]. In a real constellation, both the operational state of the satellite itself and the orbital distribution and configuration of the constellation system as a whole affect the quality of the communication links, but almost all published papers on the constellation consider these three aspects separately. Mostly, STK orbital data are imported into OPNET for one-way interaction. Moreover, there is very limited work in Modelica on the modeling of the constellation system and communication links as well. In this paper, a satellite constellation system model is developed in MWorks, and an attempt is made to couple the satellite multidomain system model, constellation system model and communication link model into a system model to achieve a multiscenario simulation of the satellite constellation system under a unified platform. Then, channels are established for an interaction between telemetry data and the Modelica model for the model to follow the state changes of the constellation entity, providing a new method for a more efficient PHM of constellations. The main innovations in this paper include: (1) the development of a common model library for satellite constellation simulation based on MWorks which supports a multidomain simulation of a satellite system, constellation orbit, configuration and ground cover simulation and communication link simulation, providing a new solution for the simulation of satellite constellations; (2) a PHM system architecture driven by a model-data hybrid being proposed for the satellite constellation which compensates for the inadequacies of traditional data-driven PHM and provides a new idea for more efficient and reliable operation and maintenance (O&M) of constellation systems. This paper's remaining part is structured as follows: Section 2 introduces the modeling theory, model architecture and implementation of the satellite constellation system. Section 3 presents the architecture of the satellite constellation PHM system based on a model-data hybrid and describes the key technologies. After that, Section 4 introduces the application results of this framework in a single constellation. Finally, Section 7 summarizes the entire paper.