200kHz LLC Converter

LLC Circuittypically operates in the high frequency range. Using traditional simulation methods, a very small simulation time step is required to get the correct results, which makes the entire simulation process very time-consuming. DSIM uses an event-driven mechanism, which greatly shortens the simulation time.

shown in the figure below is an LLC isolated two-way DC-DC converter with a variable frequency control frequency of about 200 kHz and a variable frequency square wave controller to generate a switching signal.

you want to use an existing simulation tool with a fixed step size, you must choose a very small time step. The simulation results below show the simulated waveforms of the output DC voltage Vo at different time steps. It can be observed that time steps larger than 1e-9s cannot obtain the correct waveform.

with a 1e-9s time step, existing tools take more than 20 minutes to perform a 0.1-second simulation. However, using the discrete state event driven (DSED) algorithm, the DSIM speed is increased by more than 1300 times, and it only takes less than 1 second to obtain the same result. The following figure shows the comparison of simulation results, where Vo is the output DC voltage and Vcr is the resonant capacitor voltage. The CPU of this example test platform is Intel Core i7-6600U.