Transient thermal modelling of an Axial Flux Permanent Magnet (AFPM) machine with model parameter optimisation using a Monte Carlo method

Abstract

This paper presents the development of a transient thermal model of the EVO Electric AFM 140 Axial Flux Permanent Magnet (AFPM) machine based on a hybrid finite difference and lumped parameter method. A maximum deviation between simulated and measured temperature of 2.4°C is recorded after using a Monte Carlo simulation to optimise model parameters representing a 53% reduction in temperature deviation. The simulated temperature deviations are lower than the measurement error on average and the thermal model is computationally simple to solve. It is thus suitable for transient temperature prediction and can be integrated with the system control loop for feed forward temperature prediction to achieve active thermal management of the system.

A Lumped Parameter Thermal Model for Single-Sided AFPM Machines With Experimental Validation

“…Based on the equation ( 29), the ratio of the AC resistance to the DC resistance can be obtained as Rac/Rdc=1.061. The proximity copper loss can be obtained by using the widely used 1-D analytical model shown in (30) [51], of which the order of magnitude is 10 -10 W at 300 Hz, hence it can be neglected. In (30), lactive is the active length, Bm is peak flux density.…”

“…In addition, there is no experimental validation of the transient-state LPTM in [29]. In [30], the Monte Carlo method is applied to optimize the heat transfer parameters at the boundaries of the transient state LPTM for the single sided AFPM machine. By using the Monte Carlo method, the LPTM can achieve a maximum absolute error of stator temperature of 2.4 °C during constant DC current test.…”

Green driving optimization of a series hybrid electric vehicle

“…Equations (2) model only the power losses due the resistance R g of stator copper windings, while actually there are other electromagnetic dissipation sources [23] such as Eddy current losses (∝ ω 2 g ) and hysteresis losses (∝ ω 2 g ), as well as mechanical losses [23] such as bearing losses (∝ ω g ) and windage losses (∝ ω 5 g ). These additional losses are modelled via a dissipation torque in the dynamic equation of the rotor as follows:…”

The Ventilation Effect on Stator Convective Heat Transfer of an Axial-Flux Permanent-Magnet Machine

“…D UE TO the development in high-performance rare-earth permanent-magnet technology, axial-flux permanentmagnet (AFPM) machines are an attractive solution for many applications such as hybrid and electric vehicles [1], as well as wind turbine generators [2]. Owing to the high remanent magnetic field, the use of neodymium magnets (NdFeB) can meet industry demands such as high power density, efficiency, and cost reduction.…”