In a conventional three phase Brushless DC machine with 120° electrical conduction, Harmonics and commutation torque ripple occurs because of changeover of load current from one phase to another at every 60 electrical degrees. This paper presents techniques for diminishing the harmonics and torque ripples in sensor Brushless DC motor. This torque ripple reduction techniques based on voltage controlled and current controlled algorithm, both results are simulated and compared to bring out suitable and effective method. ripple by modifying the voltage of decaying phase in commutation interval is presented in paper (3).The paper (4) presents measurement of commutation interval from the terminal voltage of BLDC motor and it is also calculates PWM duty ratio using the measured commutation interval to suppress the commutation torque ripple. This paper (5) describes a new PWM switching strategy to minimize the torque ripples in BLDC motor which is based on sensor rotor position control. A novel indirect position detection and an improved methodology to reduce the high frequency harmonics content and torque ripples using RC filter connected at the input of the BLDC motor is presented in paper (6)-(9).The harmonics and torque ripple is reduced by the voltage control method and with filter is presented in paper (9)-(11).The commutation of a brushless DC motor depends on position of rotor. The angle between magneto-motive force of stator and rotor is fixed to 90° (electrical) so the motor produces maximum torque and needs low reactive current which is useful for advance commutation by few degrees to compensate the stray inductance effects and minimize reactive current.