Drives and Controls Magazine
Integrating electronics with motors could halve power-to-weight ratios
Published:  18 July, 2013

The German government is providing €10m of funding for a collaborative project aimed at integrating electronics into electric motors, thus improving power-to-weight ratios by up to 50% and cutting system costs by up to 40%, compared to using separate sub-systems.

Although the project, called Emile, is aimed mainly at electric vehicle applications, it could also have implications for industrial motors. It could make faults easier to identify, and allow volume production to be achieved at a much lower costs.

Currently, the power and control electronics for electric vehicles are usually located in separate housings connected to the motor by cables. As well as requiring space for the electronics, the cables add to the vehicle’s weight and costs, and make the system more susceptible to faults.

If the electronics could be integrated with the motor’s stator, there would be many potential benefits. The number of interfaces and components could be reduced, saving space and weight, as well as total costs. In addition, potential sources of electrical interference would be removed.

There is also the potential for simplifying production by using pre-assembled sub-systems, as well as advantages in the areas such as fault control, redundancy, functional safety, and system efficiency.

But, at the same time, integrating the electronics with the motor will increase the thermal and mechanical demands on the electronics.

The aim of the Emile project is to integrate control and power electronics into motor stators

The Emile consortium is being led by the automotive supplier ZF Friedrichshafen. Its members include Lenze, Siemens, Robert Bosch, Volkswagen, TDK-EPC, Infineon, the Fraunhofer Institute for Integrated Systems and Device Technology (IISB), and the Institute for Power Electronics and Electrical Drives (ISEA) at the RWTH Aachen university.

The German Federal Ministry of Education and Research (BMBF) hopes that its €10m of funding will pave the way to a teamwork approach by establishing cooperation between research institutes, car companies and automotive suppliers at an early stage.

The project will also help to transfer knowledge in the area of e-mobility. Additionally, the project is expected to have spinoffs in terms of more efficient and cost-effective industrial automation systems.

The stated aims of the Emile project are to improve the power-to-weight ratios of converters and electric motors by up to 50% and to reduce systems costs by up to 40% compared to using separate subsystems. The consortium hopes to demonstrate these improvements both for passenger cars and for industrial applications.