During the 35th International Electric Vehicle Symposium (EVS) To be held in Oslo from June 11 to 15, Vitesco Technologies will present some of its new products for automotive electrification. Among them stands out a new externally excited synchronous electric motorthat is does not require permanent magnets in its rotor. In this case, the manufacturer has optimized the software of this machine to adapt it to long journeys in which electric vehicles need to reach high speeds.
A synchronous electric motor (PSM), It generally incorporates permanent magnets composed of rare earths such as dysprosium, gadolinium or neodymium. When magnetized with another magnetic field, these magnets provide a magnetic flux and do not lose their properties once the cause that causes the magnetism ceases. being iembedded in the rotor they eliminate the need to implement an external excitation system and brushes to generate the corresponding magnetic field in the rotor and make it rotate when exposed to the externally generated field in the stator.
In the externally excited synchronous motors (EESM) Instead of permanent magnets, an external excitation is used, consisting of a power supply and an inverter. The rotor’s magnetic field is generated by slip rings and brushes that require no maintenance and do not cause sparks. Their advantage is that they allow to control the power of the magnet that is created in the rotor and therefore torque requirements at all timeswhich makes them more efficient. Instead, they are motors bulkier by the extra components that the external excitation supposes.
The use of permanent magnet electric motors became industrially widespread in the 1990s. Their greatest advantage is their efficiency, 15% higher than that of conventional motors. asynchronous induction motors, reaching a higher density of available power, both gravimetric (kW / kg) and volumetric (kW / l). Its disadvantage is that including these scarce and scarcely available materials makes them more expensive to manufacture.
According to Vitesco, EESM motors are more efficient than PSM motors especially at higher speedswhich makes them particularly suitable for traversing long distances at highway speeds. A technical appreciation with which another highly prestigious engine manufacturer, such as BMW, also agrees. Its fifth generation technology already implemented in models such as the iX3, i4, iX, i7 and iX1 also uses externally excited synchronous motors.
In addition to its great efficiency at high speeds, it also costs are significantly reduced by dispensing with magnets in the motor whose purchase prices are currently at the highest levels of the last 10 years.
Vitesco’s EESM technology joins the offer of electrical systems that it already has in its catalog which includes driveshafts, drives, inverters and all associated power electronics. At the EVS Symposium in Oslo, in addition to this integrated electric drivetrain, Vitesco Technologies will exhibit systems and solutions for greater electric drive efficiency including solutions for battery management, power electronics, thermal management, a high voltage and a master controller.
“With this product portfolio, we are focusing on global and scalable platforms for electric vehicles, which is where we see growth and where the potential for more CO2-neutral and sustainable mobility lies.two”, assures Thomas Stierle, member of the Executive Board and head of Vitesco’s Electronic Controls and Electrification Technology business“.