EC: NovaTorque Gen2.0 PremiumPlus+ ECPM Motors
Motion Control: NovaTorque's new motor is a radically innovative electric motor design that uses low-cost ferrite magnets to deliver the efficiency of rare-earth permanent magnet motors at a price competitive with standard induction motors. This is a Control Engineering 2013 Engineers' Choice finalist.
NovaTorque’s Gen2.0 PremiumPlus+ Electronically Commutated Permanent Magnet (ECPM) motors use low-cost ferrite magnets in an innovative flux-focusing design to deliver the best of both worlds, the superior efficiency of rare-earth permanent magnet motors at a price that is competitive with induction motors. Driven by variable frequency drives, these motors boast motor-only rated point efficiencies of 93.0% and 92.0% for 3 hp and 5 hp versions respectively, far exceeding the levels achieved with induction motors. By comparison, 3 hp and 5 hp NEMA Premium induction motors, when driven by variable frequency drives, achieve a motor-only efficiency of between 88.5% and 90.0%.
NovaTorque’s PremiumPlus+ motors also maintain their high efficiency over a much wider speed and load range. For example, in a variable speed, variable torque application such as a fan or pump, a 50% reduction in speed results in a 75.0% reduction in load. At that reduced load, NovaTorque motors will maintain efficiency of approximately 91%, whereas a NEMA Premium efficiency induction motor will have declined to 80%. The advantage is even more dramatic when compared to the current installed base of induction motors, where improvements ranging from 20% or more are achievable.
Importantly, due to its unique patented flux-focusing stator and rotor hub geometry, the NovaTorque motor produces this performance with an all-ferrite (versus rare earth) magnet design. The cost of rare earth (neodymium) magnet material, the basis of most conventional permanent magnet motors, has risen dramatically and is now more than 25 times the cost of ferrite. Further, supply of rare earth magnets, nearly sole-sourced out of China, is increasingly uncertain. Using ferrite magnets allows NovaTorque to price its motors comparable to induction motors. This means OEMs and HVAC systems builders can now economically deliver permanent magnet motor efficiency with their systems.