Power density is the amount of power (time rate of energy transfer) generated per unit volume of the motor. The more powerful the motor in a smaller envelope, the higher the power density. Volume power density is an important consideration where space is constrained or where maximum output is needed in a fixed space. High power density enables miniaturization of applications and end devices or higher capability in current devices.
One application where power density can greatly increase performance is in battery powered Industrial Power Tools (Nutrunners, Screwdrivers, Pruning Shears). The motion profile for these applications requires a high peak torque when the tightening phase is engaged, so an increase in the power density of a motor yields higher output torque in the same tool. Conversely, the tool size required for a given torque can be reduced, allowing a smaller and lighter tool to be used. In both cases, the ergonomics of the tool are vastly improved easing the burden on the Operator over the course of the day, improving their performance on the job.
Portescap’s Ultra EC™ motors are crafted around our patented U coil technology – a new design that is key to the outstanding power density of these Brushless DC motors. The Ultra U coil uses straight copper turns to maximize the effectiveness of the magnetic field, with coil heads perfectly integrated into the compact motor design. With minimal joule and iron losses, maximum power is available to achieve the specific performance characteristics in the application. And of course, minimal losses also mean greater efficiency and cooler operation. This unique coil design allows two-pole motors, for example, to deliver 30 percent more torque compared to the same size motor using a conventional coil design, with substantially lower iron losses.