Mathematical models help to lower radio interference in EVs

Researchers in Germany are using mathematical models to reduce radio interference in electric vehicles (EVs), while making them cheaper at the same time.

According to a statement, scientists at the Fraunhofer Institute for Reliability and Microintegration IZM in Berlin are using new calculation methods to ensure EVs can access the radio without the need for expensive filters and insulation cables.

Listening to the radio in an EV is difficult because electrical interference impedes the reception of radio waves.

Dr Eckart Hoene, director of the Power Electronic Systems research group, and his team have used mathematical models to determine where in the vehicle components should be placed to keep their electromagnetic interactions to a minimum.

‘The size and position of individual components — including the electric motor, the battery, the air-conditioning compressor, the charging system, the DC/DC converter and the frequency converter itself — play a crucial role. How and in what direction cables are installed is just as important, as is the thickness of their insulation,’ said Hoene.

Interference in EVs is caused by the frequency converter, which rapidly changes electrical energy into mechanical energy and controls the electric motor’s speed and direction of rotation. However, the converter turns the electrical energy on and off every fraction of a second, which produces electromagnetic interference.

The Fraunhofer Institute is advising automotive manufacturers and suppliers in Germany and increasingly in Japan and the US.

Electromagnetic interference is not just a problem in electric and hybrid drives. It can be a problem anywhere power electronics are installed, such as in avionics or wind and solar energy facilities.

‘Roofs with photovoltaic arrays will have a solar converter to change the direct current into alternating current, and this can impair radio reception inside of houses,’ added Hoene.