Performance Analysis and the Cost Effective Position Sensorless Control of Axial Flux PM Brushless DC Motor

摘要

The aims of this paper are the simple comparison of the axial flux (AF) structures versus the radial flux (RF) structures for brushless permanent-magnet (PM) synchronous motors and proposing a cost effective position sensorless control strategy for AFPM Brushless DC Motor. The comparison is developed for different motor dimensions. Moreover, a cost effective and position sensorless control strategy proposed for AFPM brushless DC (BLDC) motor drive using single current sensor. It is based on the generation of quasi-square current waveforms, using only one current controller for the three phases. Unlike the conventional methods, the proposed method presents advantages such as very simple control scheme, without needing to triangular carrier modulation, and balanced phase currents. The proposed position sensorless technique is based on the detection of zero crossing points of three voltage functions that are derived from the difference between the lines' voltage measured at the terminals of the motor. This control algorithm is particularly suitable for cost sensitive product such as air purifiers, air blowers, cooling fan, and related home applications. The effectiveness of the proposed control system have been validated by simulation results.