Power Factor Correction for a Bidirectional On-Board Charger for Electric Vehicles and Plug-in Hybrid Electric Vehicles - A fundamental study of the bidirectional totem-pole PFC
MetadataShow full item record
- Institutt for elkraftteknikk 
With the beginning implementation of a smart grid in industrialized countries increasingthe load flexibility of customers, as well as communication with the gridoperators, a potential market for bidirectional on-board chargers (OBC) is emerging.The OBC is the electric vehicle charger located within the vehicle, operatingas a link between the DC-voltage battery and the AC grid voltage in electricitysockets anywhere, thus working at a universal voltage range (85Vrms-265Vrms)with rated power in the range of 1.9kW to 3.5kW. To maximize the real powerdrawn by these OBCs, they are designed with power factor correction (PFC) convertersat the AC grid interface, shaping the drawn AC current sinusoidally andin phase with the AC voltage, to maximize the power factor. Thus, a bidirectionalOBC would necessarily require a bidirectional PFC. In this master s thesis,a simulation model is developed for a bidirectional totem-pole PFC, attemptingto verify the use of this topology as the mentioned bidirectional OBC PFC. Thework is focused on describing the basic bidirectional operation of the bidirectionaltotem-pole PFC, deriving expressions for currents, voltages and losses, as well asfor the gate logic and control system. Average current mode control is used, withcascaded current and voltage control including PI controllers and Symmetrical optimumtuning. To verify the simulation model for the power levels and demandsof an OBC, the main components are dimensioned to achieve 98% efficiency at230Vrms, 3.5kW and 90kHz switching frequency, implementing GaN eHEMTs inthe fast-switching leg of the totem-pole. At last, simulations are performed, showingthat the PFC is able to achieve a power factor of 0.998 and a THD of 5% inboth G2V and V2G, without a DM filter on the AC side.