Position Sensorless Control of PMBLDC Motor Drive for LEV with Torque Ripple Reduction

This paper deals with a Hall-Effect position sensorlesss permanent magnet brushless DC (PMBLDC) motor drive with regenerative braking in EV application. A new rotor position estimation logic is proposed here. The rotor position information is obtained based on the line voltage comparison implemented with speed control and minimized torque ripple. The proposedsensorlesss control is a robust one against any phase lag due to the low pass filter action. A digital IIR lowpass filter is used to filter out the high frequency switching noise from the line voltage waveforms. The phase compensator is avoided here, which saves additional cost and circuit complexity. A hysteresis controller is used for speed and current control along with a position sensorless algorithm. The EV powertrain is also equipped with inherent regenerative braking capability. Thus, no additional DC-DC converter or dedicated regenerative braking algorithm is required for bidirectional current flow during energy regeneration. A high gain positive output Luo (POL) converter is implemented for efficient MPPT control. The proposed drive structure is validated using MATLAB Simulink and described in detail.