The periodic spread spectrum technologies used in converter to suppress its electromagnetic interference and noise have been applied widely, while the nonlinear phenomenon is ignored. Based on the analysis of the periodic spread spectrum technology and single-phase H bridge converter accurate stroboscopic map model, the bifurcation and chaos phenomenon of the single-phase H bridge circuit is studied and the discrete model of the H bridge sine inverter is established by means of periodic spread spectrum technology. The nonlinear phenomenon is analyzed using the time domain chart, folding map, bifurcation diagram and Lyapunov index spectrum. Results show that the H bridge sine inverter based on the spread spectrum technology can go into the chaotic region more easily when it is in the nonlinear region, and it is concluded that the frequency of cycle spread spectrum has important effect on the initial branch point position of system.