Accurate dynamic models for power converters are of great importance during the compensator design process in order to achieve a stable converter operation and a high control performance. Unfortunately, nonlinear components such as switches and diodes are inherent to switching power converters and thus the effort to derive system transfer functions is considerably higher than the work required for the analysis of linear systems. The development of high power isolated bidirectional dc–dc converters has become an urgent topic because of the requirements of fuel cell vehicle applications and battery based energy storage systems. For a power converter system with defined input and output control variables, the dynamic system behavior typically depends on the operating point, which determines the steady state values of the characteristic system variables. In this project, the system proposes a bidirectional three-level LLC resonant converter with a new pulse width and amplitude modulation (PWAM) control method. This method has three different operation modes with different voltage gains with control signals.