Analysis on EMF characteristics for torque ripple reduction in BLAC motor intended for HVLS fan application

Abstract

This paper analyzes the harmonic characteristics of electromagnetic force (EMF) in Brushless Alternating Current (BLAC) motor for High Volume Low Speed (HVLS) fan application. Vibration and noise are one of the main crucial things in HVLS fan application. It comes from torque ripples which can be detected by harmonics of Electro Magnetic Force (EMF). Commonly, there are a few methods to eliminate the noise and vibrations issue, but most literatures only focus on small motor and not intended for HVLS fan application. Thus, the objective of this paper is to eliminate the harmonics content in EMF at early stage design. Through EMF harmonics the expected torque produced could be used to select proper slot-pole number in order to eliminate the noise and vibrations issue. In here, the analysis involves three different slot-pole numbers which are 18s/20p, 12s/10p and 9s/8p BLAC model, respectively. All models have similar volume of permanent magnet. The analysis is carried out using FLUX 2D Finite Element Analysis (FEA) for EMF computational and transient torque computation. Later, Fast Fourier Transform (FFT) analysis is used to calculate the harmonics of EMF. The analysis stage includes the EMF parameter analysis, harmonics and torque ripples analysis. It was found that 18s/20p has higher output torque with the lowest 5% torque ripple value. As a conclusion, this paper presents low torque ripple in point of view of the EMF characteristics in designing HVLS fan.

Determination of performance characteristics using FEA-analytical for outer rotor BLDC motor

“…At this stage the CAD model is good to be used in FEM modelling. The selection of the stator slot and pole number is fixed based on the finding that the 18 s/20 p configuration delivers the highest output torque with the lowest torque ripple when compared to the 12 s/10 p and 9 s/8 p configurations [28].…”

Finite element method based design and performance analysis of universal motor for agro applications

“…The author analysed the core losses of the induction motor for the various steel materials [12]. The author design motor for fan application with characteristic of torque ripple reduction and improved magnetic behaviour [13], [14]. The predictive approach was applied to control the tracking problem for polysolenoid motor [15].…”