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In order to make centrifugal blowers environmentally friendly, machines with a lighter weight and a more compact size are required. Thus, the axial length of the machine needs to be minimized within the diameter limit. However, in the design methodology, losses and thermal study become very significant; thus, losses increase significantly to achieve the desired output power when the volume is excessively reduced. Moreover, due to the machine’s compact size, heat is concentrated rapidly without adequate cooling. It might lead to a temperature rise of the critical part of the machine above the safe limit, such as winding, thereby affecting its lifespan. This study considers the 225 kW high-speed permanent magnet synchronous machine (HSPMSM) with the forced air cooling axial ventilation system (FACAVS) used in centrifugal blower applications. Firstly, four different analytical models (A2–A5) in the electromagnetic analysis are derived by minimizing the initial machine’s (A1) axial length to achieve a lighter weight and more compact size with better electromagnetic performance. The best among analytical models is chosen as the A4 model with a lighter weight and a more compact structure in addition to higher torque density than A1, A2, and A3 models, and higher efficiency than A1, A2, A3, and A5 models by HSPMSM’s, optimal geometric design, and optimal material choice, respectively. Secondly, LPTN is designed to predict the entire analytical model’s thermal behavior in the thermal analysis. Investigation shows that winding temperature rises from the A4 model is maintained below winding insulation by the determined optimal axial ventilation parameters from the sensitivity analysis. Finally, different analytical models are prototyped and tested. The comparisons between predicted electromagnetic performance, winding temperature rise, and test results were carried out, and the results were found to agree with each other consistently.

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The noise and vibration level in modular‐type permanent magnet synchronous machines with fractional slot concentrated windings (FSCW) is considered to be an important design consideration, particularly for applications requiring fault tolerance. In this work, an interior permanent magnet synchronous machine (IPMSM) with FSCW is designed in a modular manner by dividing its stator windings into different arrangements having independent three‐phase sub‐modules with separate neutral points. First, the modular concentrated winding arrangement is studied to investigate the radial forces, vibration, and the associated noise level in the prototype machine having three‐phase sub‐modules under open‐circuit fault conditions. Then, another type of distributed three‐phase sub‐module winding arrangement is analysed to further investigate the vibration and noise level in the same prototype machine under the same operating conditions. A detailed two‐dimensional (2D) fast Fourier transform analysis is performed to investigate and compare the machine radial forces, induced harmonics, and sub‐harmonics for the two analysed winding arrangements. Considering the advantages and disadvantages of both the winding arrangements, the third type of mixed concentrated and distributed three‐phase sub‐modules winding arrangement is introduced in this work, combining the first two winding design approaches. A comprehensive harmonic (3D) structure, along with the vibration and noise analysis, is performed using a multi‐physics model analysis for all the winding arrangements under different three‐phase sub‐modules open‐circuit fault conditions. Lastly, the vibration levels of all the machine prototype models under different winding arrangements are experimentally validated. Moreover, the different modular types of winding arrangements are deeply investigated in this work to suggest the best winding arrangement approach that enables the machine to work in a wide range of applications requiring lower power levels or under critical, faulty, and hostile conditions. The proposed winding arrangement has reduced stator deformation with a reduced vibration and noise level under three‐phase sub‐modules open‐circuit fault‐tolerant conditions that can be used according to process requirements.