A Novel IC Measurement Without Blanking Time for Short-Circuit Protection of High-Power IPM

Intelligent power module (IPM) short-circuit protection is a key factor in improving the reliability of power electronics systems. The conventional short-circuit detection method based on monitoring the collector-emitter voltage (VCE) desaturation has a blanking time and is slow to respond to any type of shortcircuits. Furthermore, the diC/dt method cannot be used in the IPM due to the absence of Kelvin emitter. A slow short-circuit protection process can have an irrecoverable and destructive impact on the reliability of the IPM. In this paper, a new high-power IPM topology with an internally integrated shunt is designed to realize real-time current detection, which can achieve fast short-circuit detection without any blanking time. A prototype 1700 V/150 A IPM is manufactured, and a corresponding fast short-circuit protection circuit is designed. Experimental results show the effectiveness of the integrated shunt method as its performance is significantly better than that of the VCE desaturation method. The proposed IPM needs 380 ns and 1.4 μs to detect short-circuits of types I and II, respectively. The short-circuit withstand times for short-circuits of types I and II are 2.06 μs and 0.62 μs, respectively. In addition, the short-circuit energy losses for shortcircuits of types I and II are reduced by 66% and 64.3%, respectively, compared to the VCE desaturation method. The proposed method can also be used as a reference for other IPM designs.