LED current control method of dimmable LED driver with dual active bridge DC-DC converter for 1kW-class LED floodlight

This paper proposes LED current control method of dimmable LED driver with dual active bridge (DAB) DC-DC converter for 1kW-class LED floodlight. The LED current control method is discussed in detail. The conventional LED driver cannot control turn-off time of LED current because the power flows from source side to LED floodlight side only. DAB converter is a bidirectional DC-DC converter formed by two full-bridge converters with a transformer. The proposed LED driver with DAB DC-DC converter can decrease the applied voltage of the LED to LED forward voltage immediately when the LED floodlight turns off. Digital computer simulations are performed using the PLECS (Piece-wise Linear Electrical Circuit Simulation) software, to confirm the validity of the proposed method. Simulation results demonstrate that the proposed LED driver can achieve high-speed LED current control.