Double-band Hysteresis Current Controller to Reduce Switching Losses of BLDC Drive and Its Comparison with Single-Band Hysteresis

In this paper, a double-band hysteresis current controller (DBHCC) as a new switching method in feeder inverter of a BLDC motor is proposed and implemented. Then, it is compared with the single-band hysteresis current controller (SBHCC). It has been shown that in the proposed method, the average switching frequency of switches is reduced compared to SBHCC by preserving other advantages. Thus, switching losses are reduced and the lifetime of switches is increased. In addition, it has desirable effects on reducing electromagnetic interferences and noise. In addition, speed control, torque, current ripple and transient states are investigated in both states. Three-phase reference currents for hysteresis switching are obtained using a PI regulator and integrating with output signals from Hall-effect sensors. BLDC motors are used widely in the industry due to more advantages in comparison with others. In order to drive this motor, a three-level cascade half-bridge voltage source inverter with constant DC link for each phase is used. Simulation results are obtained and analyzed using MATLAB/Simulink environment.