Commutation Characteristics and Commutation Limit of DC Thyristor Motor at Starting and Low Speed Operation

Sensorless Commutation of BLDC Motor without Low Pass Filter and Phase Shifter

 In this paper, a novel sensorless commutation method for BLDC motors is presented to simultaneously eliminate phase shifter and low-pass filter. An analytical model of the motor is presented and ripples resulted from the current commutation are investigated in detail. By detecting the zero crossing points of the unfiltered voltages of the motor terminals referred to the ground and DC link, the...

Proposed Commutation Method for Performance Improvement of Brushless DC Motor

This study focused on efficiency improvement of BLDC motors via reduction of torque ripple, core loss, and permanent magnet loss. To achieve this objective, we proposed an improved 150° commutation method for three-phase permanent magnet brushless DC (BLDC) motors to improve the current waveform. Although the 120° commutation method is generally employed for a BLDC motor, the 150° commutation m...

A Novel Method for Commutation Torque Ripple Reduction of Four-Switch, Three-Phase Brushless DC Motor Drive

This paper presents an original study on the generated torque ripples of phase commutation in the Four-Switch, Three-Phase Inverter (FSTPI) Brushless DC (BLDC) motor drive which is suitable for low cost applications. Analytic values of torque ripple and commutation duration are obtained for different operation conditions. Moreover, limitation on the speed range operation caused from splitti...

Torque Ripple Reduction of Brushless DC Motor on Current Prediction and Overlapping Commutation

Based on the analysis of the principle of torque ripple with commutation time for brushless DC motor, this paper proposes a method to restrain commutation torque ripple. This method is an improved predictive current control. First, an expression is built about the torque ripple during commutation time. After analysis, the non-commutation phase current is related to torque ripple. Then, a kind o...

Partial Commutation and Traces