Abstract：We use the new solar radiation pressure model ECOMC, combined with the ECOM-9 model, to apply five IGU precision ultrarapid ephemeris for precise orbit determination. We take the final IGS precise ephemeris as the true value, and compare the accuracy of GPS satellite orbit determination. The research results show that: compared with the ECOM-9 model, the use of the ECOMC solar radiation pressure model can improve the orbit accuracy of the satellite in the radial, tangential, and cross directions, with more obvious increase in the radial direction. The orbit determination results of fast and precise ephemeris can achieve the orbit determination accuracy of 5 cm, 3.5 cm, 2.5 cm, 1.5 cm and 1.5 cm respectively using the ECOMC new solar radiation pressure model, which is better than the orbit accuracy of ECOM-9.
