Design and evaluation of new hollow rotor for high-volume-low-speed fan

• Main Author: Sulaiman, Farina
• Format: Thesis
• Language: English; English
• Published: 2024
• Online Access: http://eprints.utem.edu.my/id/eprint/28568/; https://plh.utem.edu.my/cgi-bin/koha/opac-detail.pl?biblionumber=124410

This thesis discussed the design and evaluation of a new hollow rotor for High-Volume-Low-Speed (HVLS) fan application. HVLS fan is commonly used in large areas such as factories, barns, and public places. The research focuses on BLDC motor due to its high efficiency, stability, and high performance. Induction motor is frequently used in HVLS fan industry. The main constraint of the HVLS motor is that it’s expensive and requires high maintenance. In this research, four types of BLDC motors are designed by using Permeance Analysis Method (PAM) and Finite Element Method (FEM) for HVLS fan applications. Each motor has been developed based on the same stator design and parameter with different rotor types. These are hollow rotor, spoke rotor, embedded rotor, and surface mount rotor. The PAM method is used to model the sizing equation of the HVLS motor reduced computational time. The PAM formulated the sizing equation to calculate the magnetic flux of the air gap. The FEM measured is used to analyse the characteristics of flux linkage, back emf, cogging torque, inductance, stator flux density and electromagnetic torque. The simulation results from PAM and FEM results are validated for the purpose of choosing the best rotor type design for the fabrication process. The percentage difference for each validation part is below 10 % for back emf, 9.1 % for cogging torque and 7 % for static torque. Based on the validation, a hollow rotor is chosen for prototype fabrication. A hollow rotor can maximise the flux density produced by the permanent magnet and coil by reducing flux leakage. It is confirmed that the implementation of hollow rotor design will optimised the magnetic flux and evenly distribute the air gap. The hollow rotor design was further tested for static and cogging torque characteristics. BLDC driver topology is carried out to analyse the performance of the motor connected with the drivers under loaded condition in the torque speed characterisation. In this characterisation, the value of input voltage, input current, input power, torque, output power and efficiency are measured for each type of commutation which is synchronous commutation, basic commutation and THC, in order to confirm the best topology for BLDC motor. From the topology, it can be seen that by using THC, the detailed result of the hollow rotor could be archived and examined compared to other driver topology. This thesis provides guidelines for designing and analysing BLDC motor for HVLS fan.