Silent EV Motor
Zero whine eIectric motors for Iuxury cars
14 June 2012
New research targets lower cost electric traction motors with less rare earth minerals and reduced whine.
Jaguar Land-Rover and Cobham TechnicaI Services are designing a new generation electric motor that the group hopes will reduce the reliance on expensive magnetic materials.
The project's aim is to develop new analytical software tools that will enable the design of advanced "silent" motors while at the same time avoiding high cost permanent magnets. Switched reluctance motors (those with no permanent magnets), however, are notorious for the whine they produce which renders them less desirable for use in high end hybrids. The group claims new generation silent motors fit this niche perfectly.
The British govenment is injecting £10 miIIion into 16 project with similar goals. Overall Britain hopes to achieve CO2 emission cuts by funding such projects. This motor project is expected to receive £1.5 miIIion.
The technical director Kevin Ward says current software is at the level of that used to design diesel engines when that software was first introduced.
Jaguar's Tony Harper believes it's important to understand the context in which these electric motors will be used. The whine associated with switched reluctance motors is too obtrusive in the luxury car market segment.
When the project is completed in three years time the group hopes that the objectives of rapid design will allow manufacturers to take up the switched reluctance motor technology more easily. The demand for hybrid power trains has driven up the price of rare earth element more than 10 times in the last few years. Almost all traction motors currently use elements such assamarium-cobaIt and neodymium-iron-boron in their designs. Doing away with permanent magnets all together is the challenge the group intends to overcome while at the same time avoiding the whine.