According to the standard Big Bang nucleosynthesis theory (SBBN), in the first few minutes the light elements were produced in the primordial universe. Among these created light elements, the abundance of deuterium was considered as the best baryometer to check the SBBN model. For the ²H(d,p)³H and ²H(d,n)³He processes of deuterium, the SBBN relevant energies are from 50 keV to 350 keV. An experimental measurement of the D-D fusion cross-section was carried out at the neutron generator. The experimental energy range spanned from 70 keV to 250 keV, approximately approaching the minimum energy level of D+ beam of the neutron generator. A fusion reaction chamber with eight angles and a thin deuterated polystyrene target of 121 nm were used in the experiment. A high precision digital electrometer was employed to measure the current from the target. The differential cross-sections of six energies in the energy range were measured. The differential cross-section curves obtained in this experiment were compared with the results of Institute of Modern Physics, Chinese Academy of Sciences. The comparison results indicated that the reaction channel of ²H(d,n)³He in this experiment is effected by the scattering of beam ions, especially at the large angles. The Legendre polynomials were used to fit the experimental differential cross-sections, and the coefficients of the Legendre polynomials were obtained. According to the fitting results, the integral cross-sections of different energies were extracted. The integral cross-sections of different energies were compared with the historical experimental results, such as the data of W. R. Arnold obtained in the thin window gas target experiment, the results of different no-window gas target experiments of A. Krauss, R. E. Brown and U. Greife, and the data of D. S. Leonard with a deuterated carbon target. The ratios of historical experimental data to evaluation data of ENDF/B-VIII.0 database are calculated and analyzed. Detailed results are shown in the following figure. The results revealed that the evaluation data of ENDF/B-VIII.0 database is significantly affected by the data of R. E. Brown. Moreover, U. Greife's data is systematically larger than the evaluation data and Brown's data. Then calculations of the astrophysical S(E) function were performed on the historical experimental cross-section data, from which the corresponding results are shown in the figure below. In U. Greife's paper, the part of the S(E) values larger than the compilation curve of Bosch and Hale was explained as the electron screening effect. Based on the forgoing analysis, the electron screening effect in U. Greife's experiment maybe overestimated. Follow-up work will focus on the lower energy up to 10 keV and the higher energy up to 1.5 MeV at other accelerators, delivering stronger data backing for an accurate calculation of the reaction rates of SBBN model. The datasets presented in this paper, including a brief introduction to the experimental setup, the differential cross-section data and the integral cross-section data, are openly available at https://www.doi.org/10.57760/sciencedb.j00213.00243(Please use the private access link https://www.scidb.cn/s/I3aumu to access the dataset during the peer review process)