Space astronomical detection commonly uses CCD as the main detector. However, the extreme radiation environment can affect CCD performance and, in turn, impact data acquisition. To gain a deeper understanding of the mechanisms impact on data acquisition, in this paper, based on the SRH theory, the defects effects on charge capture and release during transfer was discussed. A transfer model based on the CCD electrode level was established, and the operation principle of defects under different conditions was simulated. The model was used to simulate STP timing, and to discuss the impact of timing on data acquisition in actual use and the method of extracting relevant parameters from STP timing data, as well as the relationship between the parameters. The model assists in understanding the impact of radiation defects on CCD data transfer, simulating STP timing, and utilizing STP timing to acquire CCD defect parameters in actual applications.