Influence of the Placement Accuracy of the Brushless DC Motor Hall Sensor on Inverter Transistor Losses

Abstract

Low-power BLDC motors are often and willingly used in many drive devices due to their functional advantages. They are also used in advanced positioning systems, where their good dynamic performance parameters are used. The control systems use shaft position sensors mounted on motors, the structure of which is based on magnetic elements and Hall sensors. The aim of this article was to investigate the influence of the BLDC motor quality on the correct operation of the control semiconductor system. The article presents the effect of BLDC motor shaft observation system’s inaccuracies on the friction and current amplitudes of individual inverter keys. Waveforms of the controller phase currents are considered and recorded on a test bench that allows precise sensor position changes. In addition, the effect of sensor misalignment on power losses in individual inverter transistors is investigated. The article shows a significant influence of the motor shaft observation system’s assembly accuracy on the current amplitudes of individual driver transistors and their power losses, which makes it necessaryto consider these parameters when constructing power electronic systems.

Development of high precision digital magnetometer

“…The instrument is mainly composed of Hall sensor, constant current source, amplification circuit, analog-to-digital conversion circuit, microcontroller (MCU), keyboard and display circuit, as shown in Figure 1. A constant current source is used to drive the hall sensor [1] . When the magnetic field line of force vertically passes through the hall sheet, a small induced electromotive force will be generated, The Hall electromotive force is picked up by a self stabilizing zero and low-noise preamplifier, The signal is further amplified and conditioned by the main amplifier, and then sent to the microcontroller for software correction and real-time display after analog-to-digital conversion.…”

“…When the magnetic line of force of the magnetic field vertically passes through the hall element, Hall effect as in (1).…”

The Impact of Computational Accuracy on the Quality of Direct Drive Control

“…In the scalar techniques, the speed or torque of the motor is controlled without precise determination of the rotor position. This position is roughly estimated based on the readings from the Hall effect sensors [7,8] or via BEMF [9,10]. On this basis, the controller turns on the bridge transistors in the appropriate order, forcing the rotor to rotate.…”