Temperature Sensorless Thermal Management Strategy for Interleaving Power Converters

Abstract

Conventionally, to achieve thermal balance in interleaving power conversion systems, temperature sensor-based closed-loop control is required. However, temperature sensing is typically slow and cannot accurately measure the junction temperature of power semiconductors in real-time. To resolve this issue, this paper proposes a novel thermal management strategy for interleaving power converters. It is based on the weighted current sharing strategy and gets rid of the temperature sensors. The loss model of power semiconductors is established to characterize the thermal performance. Fast closed-loop control is implemented to achieve thermal balance. To verify the proposed concept, a two-phase interleaved buck converter is designed to serve as the case study. The results show that 1) the designed prototype can regulate the output voltage tightly to the reference; 2) the output currents of each module are balanced utilizing a current-sharing loop; 3) thermal balance without temperature-sensing is achieved using the proposed loss-sharing-loop.