Position sensorless control for four-switch three-phase brushless DC motor drives
Journal
IEEE Transactions on Power Electronics
Journal Volume
23
Journal Issue
1
Pages
438-444
Date Issued
2008
Author(s)
Abstract
This paper proposes a position sensorless control scheme for four-switch three-phase (FSTP) brushless dc (BLDC) motor drives using a field programmable gate array (FPGA).A novel sensorless control with six commutation modes and novel pulsewidth modulation scheme is developed to drive FSTP BLDC motors.The low cost BLDC driver is achieved by the reduction of switch device count, cost down of control, and saving of hall sensors.The feasibility of the proposed sensorless control for FSTP BLDC motor drives is demonstrated by analysis and experimental results.Index Terms-Brushless dc (BLDC) motor, four-switch threephase (FSTP) inverter, field programmable gate array (FPGA), sensorless control. I. INTRODUCTIONR ECENTLY, the brushless dc (BLDC) motor is becoming popular in various applications because of its high efficiency, high power factor, high torque, simple control, and lower maintenance.Conventionally, BLDC motors are excited by a six-switch inverter as shown in Fig. 1.However, cost-effective design is becoming one of the most important concerns for the modern motor control research.Some researchers [1]-[6] developed new power inverters with reduced losses and costs.Among these developments, the three-phase voltage source inverters with only four switches, as shown in Fig. 2, is an attractive solution.In comparison with the usual three-phase voltage-source inverter with six switches, the main features of this converter are twofold: the first is the reduction of switches and freewheeling diode count; the second is the reduction of conduction losses.J.-H Lee et al.[4] and B.-Kuk Lee et al.[5] both developed BLDC motor drives with trapezoidal back electromotive force (EMF) using the four-switch three-phase (FSTP) inverter: The four-space-vector scheme was used in [4], and in [5] the six commutation modes based on current control.They used position sensors to achieve commutation control of BLDC motors.However, position sensors make the total system more expensive, larger in volume, and less reliable.On the other hand, sensorless control for six-switch three-phase BLDC motors has had many successful applications.
SDGs
Type
journal article