The split ratio, defined as the rotor OD divided by the the stator OD, is one of the key dimensions defining the performance of an inrunner electrical machine. For a (relatively) fixed OD and stack length, it’s probably the most…
Finding the operating point of a motor
Finding the operating point of an electric motor is no longer as simple as it used to be. I mean, in the past, or in the textbooks and course slides we often see during our studies, it was simple. Just…
Axial versus Radial Flux – First Principles
Which is better – axial or radial flux? The correct answer is complex and depends on a million things, but here’s a first-principles comparison.
Tesla’s ‘Carbon-Wrapped’ Motor
Tesla Model S Plaid will apparently have carbon fiber retaining sleeves in their motors. Here are some thoughts on what this might mean.
Mahle Magnet-Free Motor – First Impressions
Mahle’s new EV motor is marketed with being rare-earth free and wirelessly excited, but what is the reality? Here are some first thoughts and impressions.
Computing Back-EMFs with space vectors
Here’s a no-brainer tip for you: space vectors are useful when designing electric motors. Duh. However, there’s one specific detail you might not know: they are also extremely handy when computing the back-EMF waveform, or induced no-load voltages. Specifically, they…
Computing Flux Linkages in 2D
How to compute flux linkages of a coil, using the results of 2D finite element analysis. Nice to know information, with occasional professional uses.
Evaluation of the Linear Labs HET motor
Linear Labs – have been making quite sizable waves in the recent year or so. But how revolutionary is their HET motor, really?
Pole count – The Good, the Bad, and the Ugly
Electric motors come with various number of poles. But why is that the case, and what are the benefits and drawbacks of an increased number?
Shear Stress versus Lorentz Force
Why two popular torque formulas, based on Lorentz force and magnetic shear stress, are in fact the SAME formula and thus yield identical results.