## 1 Introduction
This approach aimed to fulfill the requirements for future large-scale constellation-independent high-precision configuration maintenance [24]. [PERSON] et al. designed a novel method for two-dimensional lattice-preserving flower constellations that maintained the initial distribution of satellites and the initial symmetries over time, i.e., relative station keeping. Moreover, the amount of fuel required to achieve the absolute station keeping with this procedure was very low. Relative and absolute station-keeping methods for the maintenance of a constellation were established for \(J_{2}\) perturbations [25]. For low Earth orbit (LEO) near-circular satellites, the nominal semi-major axis and orbital inclination of satellites within the same orbital plane in a constellation should be consistent. The perturbation and drift patterns of the orbital elements for these constellations are also uniform. However, in practical engineering applications, initial deviations in the capture of satellite orbital elements (such as pre-bias in the orbital inclination) can occur, which may be negligible but will cause the constellation configuration to drift over time. When the phase angle deviation exceeds the permissible theoretical threshold, adjustmentsto the satellite phase angle are required. Therefore, maintaining the constellation's station position primarily involves maintaining the satellite phase. At present, the research objects of satellite positioning are mostly independent satellites or small satellite constellations, and there is relatively little research on the station keeping of large-scale low-orbit constellations. At the same time, the configuration maintenance of large-scale constellations is more stringent, and the cost constraints are more prominent. Therefore, based on the station keeping of a single satellite or a small-scale satellite constellation, this paper conducts research on the configuration maintenance strategy of large-scale low-orbit constellations. This article proposes a large-scale constellation phase-keeping loop control method based on a fixed reference star and a relative phase control method for large-scale constellations based on a dynamic reference star, thus providing the necessary conditions for the station keeping of large-scale low-orbit constellations. At the same time, a phase-keeping loop control scheme combining semi-major axis overshoot control and passive control and a relative phase maintenance scheme based on dynamic reference satellites are designed. During the initialization and configuration maintenance processes of large-scale low-orbit constellations, most satellites use continuous and efficient low thrust to complete the orbital maneuvering tasks for constellation networking. For example, during the constellation initialization stage, tasks such as raising the satellite orbital altitude and adjusting the eccentricity are carried out, and during the constellation configuration maintenance stage, tasks like maintaining the satellite phase angle are performed. This paper is structured as follows. Section 2 presents the analysis of the constellation station-keeping methods. In Sections 3 and 4, the absolute and relative control models for constellations are established, the phase-drift and phase-keeping rules of satellites are analyzed, and the corresponding station-keeping strategies are evaluated and validated. In Section 5, the simulation results are presented to assess the impacts of various control strategies on the constellation availability and operational costs, with a focus on minimizing costs. Finally, Section 6 presents the conclusions and further discussion.