Motor vehicle's electrical power steering operating method, involves reducing heat produced in semiconductor switch by modifying pulse wave modulated pattern so that determined temperature difference does not exceed preset limit value

摘要

The method involves thermally, operatively connecting a semiconductor switch (202) with a cooling or housing body (201). The temperature of a base plate is determined, and the temperature of the semiconductor switch is determined. The temperature difference is determined between the base plate and the semiconductor switch. The heat produced in the semiconductor switch is reduced by modifying pulse wave modulated pattern so that the determined temperature difference does not exceed a preset limit value. An independent claim is also included for a control or regulating unit for operating an electrical power steering.