Electro Kinetic Designs EKD EKD EKD Outsourced design engineering EKD Electro Kinetic Designs
outsourced design engineering
for specialised electrical machines

EKD Motor design



Challenging the conventions


Traditionally, motors and generators have been classified according to their size or power output, and terms such as 'fractional horsepower' or 'low integral horsepower' are frequently used. However, the increasing use of advanced materials in modern, efficient designs means that the long-established performance norms are being challenged.


Motors of small physical size can have astonishingly high short-duty performance. Motors which are large in diameter can still be small in volume if they have a large hole through the middle or are short in length.


At EKD, we prefer to think in terms of the underlying fundamentals, such as electric current density, magnetic flux density, saturation effects, transient and teady-state temperature rise, and the effect these variables have on the constructional materials.



Electro Kinetic Designs Ltd. Alastair Flew

Design expertise


EKD have experience of most frame sizes, power outputs and supply types. The following list provides a guide to our particular areas of expertise:


  • Power output: 1 W to 50 kW
  • Speed range: Standstill to 250,000 rpm
  • DC power supplies: 3 V to 600 V, current up to 250 A
  • AC power supplies: 115 V to 415 V, 1 phase, 3 phase, 50 Hz, 400 Hz, Wild frequency
  • Frame sizes: 10 mm diameter to 300 mm diameter


EKD are particularly knowledgeable about applications involving high power density and short duty cycles. We are also highly proficient at designing for harsh environments, whether at extremes of temperature and pressure, shock and vibration, or immersed in aggressive fluids or explosive atmospheres.


Design detail


EKD can undertake the design of the entire electrical machine, not just the electromagnetics. This includes the mechanical design, the thermal design, the materials selection and the drive electronics.


By having a thorough understanding of the design of a machine, we can define performance and predict reliability under specified environmental conditions. We know the ins and outs of redundant windings and lane separation, and the issues surrounding fault propagation. And we understand the safety issues associated with all the various different applications where our designs see service.

Conversion factors, Formulae and Constants


Disclaimer: This page contains conversion factors, formulae and constants. The data is believed to be correct and we use it ourselves, but we will not accept liability for problems arising from errors or inaccuracies. If your application is critical, we recommend you cross-check with other sources.


Download conversion factors





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Electro Kinetic Designs™

Total design, based on knowledge and expertise,
not guesswork or optimism.

Tel +44 (0) 1600 735006

Electro Kinetic Designs Ltd. Company Number 5294966
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