Analysis of Clamped Inductive Turnoff Failure in Railway Traction IGBT Power Modules Under Overload Conditions

Abstract

This paper studies the overload turnoff failure in the insulated-gate bipolar transistor (IGBT) devices of power multichip modules for railway traction. After a detailed experimental analysis carried out through a dedicated test circuit, electrothermal simulations at device level are also presented. The simulation strategy has consisted in inducing a current and temperature mismatch in two IGBT cells. Results show that mismatches in the electrothermal properties of the IGBT device during transient operation can lead to uneven power dissipation, significantly enhancing the risk of failure and reducing the lifetime of the power module. Concretely, simulations qualitatively demonstrate that localized hot-spot formation due to a dynamic breakdown could lead to a second breakdown mechanism.Index Terms-Insulated-gate bipolar transistor (IGBT) power module, power inverter reliability, railway applications, semiconductor device breakdown, semiconductor device thermal factors.

Reliability and Lifetime Prediction for IGBT Modules in Railway Traction Chains

“…This can give rise to very stressful processes in terms of instantaneous dissipated power during both the diodes reverse recovery and the IGBTs turn-off, i.e., ruggedness failures when high current and high voltage levels coexist (Perpiñà et al, 2010a). Besides, IGBT modules are also the most sensitive elements to other system failures.…”

“…In this failure scenario, it is interesting to determine "a posteriori" the device failure signature so as to derive precious information about the device failure origin. Over the years, this analysis has been tackled in both diodes and IGBTs, providing a physical insight into the failures occurred during the diode reverse recovery and the IGBT turn-off under inductive loads (Perpiñà et al, 2010a). Obviously, the working conditions for such components can be more adverse when the power module wears out by thermal fatigue, as can be inferred from their derived failure mechanism explained in the next subsection.…”

“…In this framework, semiconductor power devices are responsible for diverting and switching the electrical current (rectifiers and power switches, respectively) among the different branches of the power converter, supporting high current and voltage ratings under working conditions. Such extreme working conditions fix their reliability problems, since they usually arise either from the ruggedness of such devices to non-desired electrothermal events (Perpiñà et al, 2007a(Perpiñà et al, , 2010a) (e.g., short-circuit, overvoltage, overcurrent, or overtemperature) or from the ageing of one of the power converter constituting elements (Ciappa, 2002;Malagoni-Buiatti et al, 2010) (e.g., capacitors, bus bar or power device packages). Both phenomena have a negative effect on power devices: their working conditions become more adverse (overload conditions in terms of current, voltage or temperature), eventually causing their explosion.…”

“…A perfect thermal contact between an IGBT power module and its cooling system is not always assured all over the module backside (uneven thermal resistance along the module backside), as evidenced in (Hamidi, 1998a;Perpiñà et al, 2010b). Then, the addition of both effects can provoke that some components reach temperature values, which lead to their destruction by burn-out (Sankaran et al, 1997;Ciappa, 2002;Perpiñà et al, 2010a).…”

Observer based dynamic adaptive cooling system for power modules

“…In wear-out mechanism, thermo-mechanical stress plays a very important role in affecting power electronic devices/modules reliability [1,5], such as the fractures propagation and degradations in solder layers [6], wire-bond lift-off [7] and emitter metallization [8]. The failure mechanisms are influenced by both environmental and load conditions [9,10]. To address this issue, research has addressed different aspects, for example, new semiconductor and materials technologies [11,12], package architecture [13], interconnection [14], control of power electronic modules [15] and advanced cooling technologies [5,16].…”