Reliability and long operating life have been central design themes in the development of NovaTorque's motor technology. Many failure modes common to the motor industry have simply been designed out.
Cooler Operating Temperature
Most of those failure modes are heat-related. High motor temperature leads to bearing lubrication and/or winding insulation deterioration and eventual failure.
The high operating efficiency of the NovaTorque motor reduces heating due to losses, allowing the motor to run cooler, hence inherently improving reliability.
Additionally, as the coils are directly exposed to the exterior of the motor, what heat is produced is dissipated more efficiently, further reducing the operating temperature of the motor.
The electrical wind of the NovaTorque motor is a compact bobbin-type with no end-turns. The simple nature of the winding improves reliability, since less stress is placed on the wire conductor during the winding operation, as compared to a conventional 'stitch wound' motor.
Magnet Selection and Mechanical Integrity
The magnets used in the NovaTorque motor are mechanically AND adhesively restrained. This ensures that no motor failures will result due to magnet de-lamination, as can occur with surface-mounted magnets in conventional PM motor designs.
Further, the magnets in the NovaTorque motor are all ferrite. In addition to their cost advantages, ferrite magnets, unlike rare-earth magnets, are not susceptible to demagnetization at elevated temperature.
Larger, More Robust Bearings
The bearings in the NovaTorque motor have been purposefully oversized, reducing wear and extending life.
Production Quality Assurance
In addition to designed-in reliability features, NovaTorque performs rigorous tests throughout the production process for early detection of potential manufacturing defects. Tests are performed on individual parts, sub-assemblies, and final assemblies.
Individual parts are lot sampled per standard AQL processes.
Critical elements, such as hubs, rotor subassemblies, and stators are 100% tested before final assembly for critical mounting dimensions, the level and uniformity of flux output, high pot and electrical continuity, and balance.
The final assembled motors are 100% tested for high pot, Ke (volts/KRPM), efficiency at several operating points, and shaft run out.
Final assembled motors are also sample tested for vibration, detent (cogging torque), Kt (N-m/amp), inductance, and no load losses. The root cause for any deviation from specification is identified and quickly addressed.