Higher slot fill factor, higher efficiency: Cast Coil sets new standards

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The advantages of our high slot fill factor

Electric motors have become an integral part of modern life. They can be found in countless applications, from household appliances, aircraft, pedelecs and vehicles to wind turbines and industrial machinery. The development of more efficient and powerful electric motors is therefore an important goal in order to reduce energy consumption and protect the environment.

Our Cast Coil technology is a new technology that has the potential to revolutionize the electric motors of the future. One of the key factors is the high slot fill factor.

What is the slot fill factor?

The slot fill factor describes the ratio of copper in the conductor cross-section to the total slot area. – The area in the motor that is available for the coil. The higher the slot fill factor, the more copper (or aluminum) there is in the slot and the more power and torque the motor can provide with higher efficiency.

Conventional wound coils with round wire achieve a slot fill factor of around 55%. – The rest is air, which contributes nothing to performance and represents a resistance to heat dissipation. Cast Coils on the other hand can reach up to 90%.

Why is a high slot fill factor so important?

A high slot fill factor leads to several advantages:

Higher efficiency: the high slot fill factor brings better heat dissipation and leads to higher motor efficiency. This means that the motor consumes less energy to deliver the same power. As a result, the operating costs or “Total Costs of Ownership” (TCO) are reduced.

Higher performance: The high slot fill factor – more active material in the same installation space – of Cast Coils enables the motor to generate more torque and power in the same installation space. This increases power and torque density.

More compact design: Due to the more efficient conductor material (copper or aluminum), e-machines with Cast Coils can be built smaller and lighter with the same performance data as with wound coils.

High current density: Due to their geometric shape, Cast Coils offer a larger conductor cross-section and can therefore allow higher current densities. Compared to wound coils, up to 50% higher at the same temperature under continuous load! Cast coils therefore offer particular advantages for devices with low voltages and high currents.

Cast Coil: The ideal solution for many applications!

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