DThe shift to electric vehicles has brought some changes. In the German automotive industry, there are 180,000 jobs on the verge of bankruptcy, of which 95,000 jobs come from suppliers that currently produce engine and gearbox parts. This is the result of a study published by Agora Verkehrswende and the Boston Consulting Group in early July. Although the author calculates that other industries or companies will create a similar number of jobs, this may be uncomfortable for high-income metal workers. For some time, major suppliers have been working hard to create a necessary virtue and invested in the development of electric drives. However, do they provide enough potential for technological differentiation to enable German companies with a cost structure to compete with Chinese competitors?
At least Swabian foundation companies Bosch and Mahle, which do not need to position themselves in the short-term capital market, are participating in this struggle. In the past few weeks, you have demonstrated new developments in European engineering art. MAHLE introduced a new type of separately excited synchronous motor that does not require sliding contacts to work. The related innovation leap is roughly as large as the leap from the intake manifold to direct gasoline injection.The best way to understand it is to look at the machine the developer uses Electric car Currently available. For example, the permanent magnet synchronous motor used by Porsche provides the highest power density. In such a motor, the magnetic material in the rotor ensures that the stator will rotate once it is supplied with alternating current. However, once the rated power is reached, the magnetic field must be actively weakened, which will reduce the efficiency at high speeds. In addition, permanent wake-ups are related to heavy use of resources. Because in a 140 kilowatt motor, there are about two kilograms of magnetic materials, including rare earth neodymium and dysprosium.
Therefore, the widely used asynchronous motor that induces current in the rotor winding has a lower cost. Especially at low speeds, the efficiency is significantly lower than that of permanent magnet excited motors.
Separately Excited Synchronous Motor
The third option is to use electromagnets as the rotor, that is, a single coil with a ferrite core.Separately Excited Synchronous Motor Reno Zoe The setting is impressive-compared to asynchronous motors-with significantly higher efficiency, because rotor excitation only requires one to three percent of the total power. However, so far, this type of machine has a major disadvantage: the current required for magnetization flows into the rotor through the sliding contacts. What grinding will produce friction and wear. Mahler has now found a way to transmit power without contact. For this purpose, a small resolver firmly connected to the stator is used. The second winding to which the current is induced is located on the rotor side. The component itself is not conspicuous and hardly bigger than a coffee cup. However, there is considerable manufacturing knowledge in terms of control: transmission is through alternating current, so the motor output can be adjusted by phase shift. The current reaching the rotor side is then converted back to the direct current required by the electromagnet.
The losses incurred are small. The map released by Mahle shows that not only at the optimal point, but also at a wide speed range, the efficiency exceeds 94%. “Regardless of your personal driving situation, this will allow you to get more mileage,” explains Martin Berger, the company’s research director. Since many car manufacturers want to manufacture their own electric motors, Mahle not only provides complete electric motors, but also wants to sell the induction power transmitter as a component independent of the supplier. “That will be the crankshaft of the electric motor,” Berger said. However, it will take several years for this engine to enter the first production car.
