The LLC topology converter includes a resonant cell (resonant capacitor + resonant choke) and a power transformer. Figure 1 shows a Premo kit box that includes all the magnetics components needed to operate the two stages of a 22 kW on-board charger:
2 x (½ resonant choke + 11kW transformer + ½ resonant choke) = 22kW
This kit box includes optimized molded integrated magnetics that can be implemented directly in the converter of our customers developing 22kW OBCs. The AECQ200-qualified unit optimized for an on-board charger applications integrates split resonant chokes and deliver optimum power density, efficiency and performance. With a footprint of just 213x73mm and only 67mm high, this magnetic component kit has a power density of 19.5kW/dm3. Its thermal transfer is maximized by a heat conductive aluminium casting.
Typically, the electrical system of EV/Plug-in HEV involves three types of converters: an On-Board Charger taking the mains to the HV battery, a DC/DC converter connecting the HV battery to a low voltage 12V battery / 12V network and a traction converter providing power from the HV battery to the engine.
The most common electronic topologies for these converters include an LLC topology for the On-Board Charger, an ZVS topology for the DC/DC converter and a power inverter for the traction converter.