Regulated cooling for reduced thermal cycling of power devices

This paper presents an innovative regulation methodology for power electronics cooling, aimed primarily at improving system reliability by reducing the amplitude of thermal cycles. We refer to forced-convection air-cooling and derive a regulation law to tune the speed of the fan according to the variations of the load and environmental conditions (i.e., the power dissipation and ambient temperature) to keep the temperature at a given location of a power assembly constant. We present theoretical analysis, simulation, hardware development and experimental data. Our focus is on typical working conditions of automotive applications, but the idea can be applied various applications.