Design and evaluation of a polyphase brushless DC-machine direct drive system

Abstract

The paper describes the design, analysis, simulation, modeling and control implementation of a high-torque low-speed multi-phase permanent magnet brushless dc machine. The main focus is on issues regarding the high level modeling comprised of a transient model in conjunction with their corresponding experimental evaluation. Analyses are made to put together modeling efforts with the expected behavior so as to have realistic simulation results verified by the experimental set-up. A DSP system control is used for comprehensive experimental results, which corroborate the work.

A microcontroller based five phase BLDC motor drive

“…Their corresponding derivatives are denoted as From equation (7), for any phase i, back EMF can be written as From equations (1), (2), (3), (4), (5) and (12) From equation (9) Using equations (8), (12) and (18) Combining all relevant equations, state space model of the system is as follows…”

“…There are two types of stator windings variants: trapezoidal and sinusoidal motors [4,5]. This differentiation is made on the basis of the interconnection of coils in the stator windings to give the different types of back EMF.…”

A high-torque low-speed multiphase brushless machine-a perspective application for electric vehicles

“…In general, if stator leakage inductance and resistance are neglected, the output power for any machine can be expressed as (1) where is the phase number, and the EMF and are the phase air-gap electromotive force (EMF) and its peak value, and are the phase current and its peak phase current, is the period of one cycle of the EMF, and the factor is the electrical power waveform factor. Equation (1) shows that a higher number of phases allows higher power density; the rationale for choosing a five-phase motor for this application has been presented in [9] and [10]. Fig.…”