| In power converter system,the reliability of IGBT（insulated gate bipolar tran-sistor）module is facing huge challenges due to complex operating conditions,harsh operating environment and strict safety operating requirements.Temperature stress is the main reason that affects the reliability and aging failure of IGBT modules.At present,the online extraction of Tj（junction temperature）and aging information in power converters is difficult to achieve.Therefore,studying the method of extracting the Tjand aging information in the power converter will provide more help for planning the maintenance and replacement of the IGBT module on the basis of improving the working reliability of the power converter.This article builds a high-precision IGBT behavior model,which can be used to discover and analysis new TSEP（temperature sensitive electrical parameters）,as well as to study the characteristics of TSEP based on the behavior model and double pulse topology.This paper studies the influence of Tj,parasitic parameters,different electrical parameters on TSEP,and provides guidance for the application of these TSEP in actual power converters.This article first studied the online extraction of TSEP of IGBT module in the power converter.For this reason,an Vce（collector-emitter conduction voltage）online monitoring circuit is proposed.The measurement circuit uses a zener diode series diode as a clamping circuit to isolate the impact of high voltage on the measurement circuit.Compared with the traditional measurement circuit,it can improve the measurement accuracy while making the circuit simpler and more reliable,and can suppress the oscillation problem of the traditional circuit under bad conditions.This paper also studies the negative voltage overshoot problem of this kind of measurement circuit topology,the selection of key device parameters and the measurement performance.The double-pulse experiment platform was built,and the double-pulse experiment verification of the measurement circuit was finally completed.Then the application of Vceonline monitoring circuit in power converters is studied,this paper completed the off-line correction of the Vceparameters under the load current based on the Vcemonitoring circuit,and proposed its Tjmonitoring process.A low-power experimental platform for the traction rectifier was built,and the Vceonline monitoring circuit and isolation circuit were experimentally verified.The effectiveness of the isolation circuit in preventing the interference between the AD sampling circuit and the power loop was verified.The measurement circuit can work normally in the low-power experimental platform of the traction rectifier,and finally the effectiveness of the Tjmonitoring method based on the measurement circuit is verified.Finally,in order to study the extraction of IGBT module aging information and the universal applicability of the measurement circuit proposed in this paper,this paper designs and builds an accelerated aging experiment platform,and monitors the Vceof the module under test,and finally uses the Vceunder small current to monitors the IGBT module’s Tj,verify the effectiveness of the Vceonline monitoring circuit. |
