Analytical methods for electromechanical forces and torque computation in brushless permanent magnet machines

The calculation of electromechanical forces that are present in a machine due to the magnetic field set up by current-carrying conductors and coils, especially when in the presence of permeable iron, is one of the most important and difficult problems in the vast field of the theory and design of electrical machines. It is a problem, moreover, which is usually dealt with by empirical methods based upon test results or by the use of numerical techniques such as Finite Element Analysis (FEA).

In this thesis, analytical formulas are developed to evaluate the electromechanical forces and torques involved in brushless surface-mounted permanent magnet machines directly from, design parameters. In the first model, a slotless stator design is assumed while in the second model, the conductors are considered as being embedded in the stator iron. Both the models thus developed are then tested by means of a numerical method (FEA) and their utility in performing parametric studies is demonstrated in the case of the first model.