CN-121997726-A - IGBT module service life prediction method and system based on running and non-running states by comprehensively considering electric-thermal-force coupling effect

CN121997726ACN 121997726 ACN121997726 ACN 121997726ACN-121997726-A

Abstract

The invention provides a service life prediction method and a service life prediction system for an IGBT module based on running and non-running states by comprehensively considering electric-thermal-force coupling effect. The method is based on the input of the circulation temperature difference delta T, the total thermal circulation times, the total thermal mechanical stress and the like, and key parameters required by multi-model joint prediction are obtained through parameter identification. The system fuses four types of life models, including an improved Coffin-Manson thermal cycle fatigue model, a physical life model based on thermal expansion stress, an Arrhenius temperature accelerated aging model and a runtime damage model. Under the running state of the device, the system calculates junction temperature by using power loss and extracts temperature cycle characteristics through rain flow counting to realize multi-model weighted life prediction, and under the non-running state, time-dependent loss is estimated based on time and a temperature sequence. And finally evaluating the residual life of the IGBT through accumulated damage. The method can adapt to multiple working conditions, improves the life prediction precision, and is suitable for health monitoring and predictive maintenance of power electronic equipment.

Inventors

HAN WEIJI
LI JIAXIN
REN DEZHI
KONG FANGYUAN
GENG CHANGYOU
ZHENG XINYI
MAO ENKAI
YU HAO

Assignees

上海交通大学

Dates

Publication Date: 20260508
Application Date: 20260112

Claims (11)

1. The IGBT module life prediction method based on the operation and non-operation states by comprehensively considering the electric-thermal-force coupling effect is characterized by adaptively switching and fusing a multi-physical failure mechanism model to perform life damage assessment based on the identification of the working states of the IGBT module, and comprises the following steps: s1, acquiring electrical parameters and environmental parameters of the IGBT module in a target system in real time, wherein the electrical parameters at least comprise collector current and collector-emitter voltage, and the environmental parameters at least comprise environmental temperature; S2, judging whether the IGBT module is in an operating state or not based on the electrical parameters; S3, if the IGBT module is in an operation state, executing an operation state damage assessment flow, wherein the operation state damage assessment flow comprises the steps of S3.1, calculating the instantaneous power loss of the IGBT module according to the electrical parameters, S3.2, calculating a junction temperature time sequence curve of the IGBT module through a thermal network model based on the instantaneous power loss and the environmental temperature, S3.3, carrying out rain flow counting analysis on the junction temperature time sequence curve, extracting characteristic parameters of effective thermal cycles meeting an amplitude threshold, wherein the characteristic parameters at least comprise a cycle amplitude delta T and cycle times, and S3.4, parallelly executing damage calculation of a first physical model and a second physical model based on the characteristic parameters of the effective thermal cycles: A first physical model, namely a Coffin-Manson fatigue model based on a material fatigue mechanism, calculating a cycle amplitude value T-induced thermal fatigue damage D C , a second physical model, a thermo-mechanical stress model based on thermo-mechanical coupling mechanism, calculating the cyclic amplitude from the cyclic amplitude Package thermal stress damage D s caused by T; S3.5, the thermal fatigue damage D C and the thermal stress damage D s are subjected to a first preset weight coefficient And (3) with Performing weighted fusion to obtain the operation state comprehensive damage D op , wherein + =1; Step S4, if the operation is in the non-operation state, executing a non-operation state damage evaluation flow: s4.1, obtaining standing time length and corresponding environmental temperature sequence of the IGBT module in a non-running state; S4.2, based on the environment temperature sequence and the standing time length, performing damage calculation of the third physical model and the fourth physical model in parallel: a third physical model, namely an Arrhenius temperature accelerated aging model based on chemical reaction dynamics, calculating chemical aging damage D A caused by the combined action of temperature and time; A fourth physical model, namely calculating a pure time accumulation damage D T based on a time damage model of a time accumulation effect; S4.3, the chemical aging damage D A and the pure time accumulated damage D T are subjected to the process according to a second preset weight coefficient And (3) with Weighting and fusing to obtain the non-operation state comprehensive damage D non , wherein =1; Step S5, accumulating the operation state comprehensive damage D op and the non-operation state comprehensive damage D non into the historical accumulated damage total amount D total based on a linear accumulated damage criterion; And S6, judging whether the updated historical accumulated damage total quantity D total reaches a preset failure threshold value D fail , if not, calculating and outputting a residual life prediction value of the IGBT module based on the historical accumulated damage total quantity D total , and if so, outputting an end-of-life early warning.
2. The method for predicting the service life of the IGBT module based on the running and non-running states by comprehensively considering the electro-thermal-force coupling effect according to claim 1, wherein the S3.2 thermal network model calculates the junction temperature of the IGBT by adopting the following formula: Wherein, the Is heat capacity; Is the thermal resistance of the junction to the shell; ; Is the loss power; is ambient temperature; The junction temperature.
3. The method for predicting the life of an IGBT module based on both operational and non-operational states taking into account electro-thermo-mechanical coupling according to claim 1 or 2, wherein the rain flow is used to extract the temperature cycle amplitude from the junction temperature sequence Only a cycle amplitude greater than a preset threshold is retained as an effective thermal cycle.
4. The method for predicting the life of the IGBT module based on the operating and non-operating states by comprehensively considering the electro-thermal-force coupling according to claim 1, wherein the thermal fatigue damage D C is calculated by the Coffin-Manson fatigue model in step S3.4, and the formula is as follows: = Wherein, the As a reference number of life cycles of the engine, In order to provide a fatigue index, the fatigue strength, As a function of the temperature-dependent correction factor, The device fails when the cumulative value of the damage to the service life of the device caused by one cycle is 1.
5. The method for predicting the life of the IGBT module based on the operating and non-operating states by comprehensively considering the electro-thermal-force coupling according to claim 1, wherein the thermal mechanical stress model in step S3.4 calculates the transient thermal stress damage D s according to the following formula: Wherein, the In order to provide a coefficient of thermal expansion, For the young's modulus, In the event of a thermal stress, In order to be able to withstand the sum of the thermal stresses, And the accumulated thermal stress damage caused by one cycle is 1, so that the device fails.
6. The method for predicting the life of the IGBT module based on the operating and non-operating states by comprehensively considering the electro-thermal-force coupling according to claim 1, wherein the Arrhenius temperature accelerated aging model in step 4.2 calculates the chemical aging damage D A according to the following formula: = Wherein, the In order to activate the energy of the device, Is a boltzmann constant, As a reference to the temperature of the liquid, The recommended service time for manufacturers, t is the dead time of the IGBT in the non-running state, In the Arrhenius temperature accelerated aging model, AF reflects the aging rate acceleration times due to temperature changes (from the reference temperature T ref to the actual operating temperature T), and the larger the AF value is, the more remarkable the acceleration effect of temperature increase on material aging is, so that the life damage (D A ) caused in the same time is larger, D A = The proportion of life damage resulting from accounting for the temperature acceleration effect into the actual non-operating dead time t.
7. The method for predicting the life of the IGBT module based on the operating and non-operating states by comprehensively considering the electro-thermal-mechanical coupling according to claim 1, wherein the equation for calculating the pure time cumulative damage D T by the time damage model in step 4.2 is as follows: Wherein, the To disregard the life damage of the IGBT in the non-operating state of the IGBT under temperature acceleration, Indicating the expected total useful life (typically in hours) of the IGBT module in the non-operating state.
8. The method for predicting the life of an IGBT module based on both operational and non-operational states with integrated consideration of electro-thermal-mechanical coupling according to any one of claims 1 to 7, wherein the integrated life damage is obtained by proportional weighted summation of a Coffin-Manson damage under operational state, a stress damage, and a temperature acceleration damage and a time damage under non-operational state, and the integrated damage limit does not exceed a preset upper limit value to avoid numerical divergence.
9. The method for predicting the life of an IGBT module based on both operational and non-operational states taking into account the combined electro-thermal-mechanical coupling according to any one of claims 1 to 7, wherein the first predetermined weight coefficient , And the second preset weight coefficient , And the variable parameter is a fixed value or is dynamically adjusted by an adaptive algorithm according to at least one of historical degradation data, current working stress level and material batch characteristics of the IGBT module.
10. The method for predicting the life of the IGBT module based on the running and non-running states by comprehensively considering the electric-thermal-mechanical coupling effect according to any one of claim 1, further comprising the steps of S7, periodically repeating the steps S1 to S6, establishing a degradation track of the historical accumulated damage total quantity D total of the IGBT module changing along with time, and based on the degradation track, performing extrapolation prediction on a future life decay trend by using a time sequence prediction model or a machine learning model.
11. An IGBT module lifetime prediction system for implementing the lifetime prediction method of any one of claims 1 to 10, the system comprising: the data acquisition module is used for acquiring the electrical parameters and the environmental parameters of the IGBT module in the target system in real time, wherein the electrical parameters at least comprise collector current and collector-emitter voltage, and the environmental parameters at least comprise environmental temperature; The state identification and scheduling module is connected with the data acquisition module and is used for judging whether the IGBT module is in an operating state or not based on the electrical parameters and generating a corresponding model scheduling instruction; an operational state impairment calculation module, coupled to the state identification and scheduling module, configured to be initiated in response to an operational state scheduling instruction, and comprising: -a loss and junction temperature calculation unit for calculating a power loss from the electrical parameter and a junction temperature timing curve based on a thermal network model and the ambient temperature; -a rain flow counting and feature extraction unit for analysing the junction temperature timing curve and extracting feature parameters of the effective thermal cycle; -a first parallel model calculation unit comprising a Coffin-Manson model calculation subunit for calculating thermal fatigue damage and a thermo-mechanical stress model calculation subunit for calculating thermal stress damage; the first weighted fusion unit is used for fusing the thermal fatigue damage and the thermal stress damage according to a first preset weight and outputting comprehensive damage of the running state; A non-operational state impairment calculation module, coupled to the state identification and scheduling module, configured to be initiated in response to a non-operational state scheduling instruction, and comprising: -an environmental data recording unit for acquiring and recording a rest time length and an environmental temperature sequence of the IGBT module in a non-operating state; -a second parallel model calculation unit comprising an Arrhenius model calculation subunit for calculating chemical aging damage and a time damage model calculation subunit for calculating pure time cumulative damage; The second weighted fusion unit is used for fusing the chemical aging damage and the pure time accumulated damage according to a second preset weight and outputting the comprehensive damage in the non-running state; The damage fusion and accumulation module is respectively connected with the operation state damage calculation module and the non-operation state damage calculation module and is used for receiving and accumulating the operation state comprehensive damage and the non-operation state comprehensive damage, updating the historical accumulated damage total amount, comparing the historical accumulated damage total amount with a preset failure threshold value, and calculating and outputting a residual life prediction value or a life end early warning signal of the IGBT module based on a comparison result.

Description

IGBT module service life prediction method and system based on running and non-running states by comprehensively considering electric-thermal-force coupling effect Technical Field The invention belongs to the technical field of life prediction of power semiconductor devices, in particular to an IGBT module life prediction method and system based on operation and non-operation states by comprehensively considering electric-thermal-mechanical coupling, which are suitable for health monitoring and predictive maintenance of power electronic equipment. Background An Insulated Gate Bipolar Transistor (IGBT) module is used as a core component in power electronics, and its long-term reliability directly affects the overall life and operational safety of the system. Failure of the IGBT mainly results from power device solder layer fatigue and package structure thermal stress accumulation under temperature cycling. Therefore, accurately predicting the service life of the device has important significance for realizing predictive maintenance and reducing operation and maintenance cost. At present, junction temperature calculation and life assessment methods based on an electric-thermal coupling model have been widely studied. For example, prior art document "method for calculating junction temperature of IGBT module based on electric-thermal coupling model" (CN DOI:10.13234/j. Issn. 2095-2805.2016.6.23) discloses a method for predicting junction temperature based on electric-thermal coupling model. And then, inputting a thermal model according to the power loss, and solving the transient junction temperature change process of the device. The system structure generally comprises a loss calculation module, a thermal resistance and heat capacity network model, a junction temperature simulation module and a waveform extraction module. The method comprises the whole flow of (1) calculating conduction and switching loss, (2) solving temperature response through an equivalent thermal resistance-heat capacity network (Rth-Cth), (3) obtaining junction temperature change waveforms of IGBT and FWD, and (4) analyzing influence of temperature fluctuation amplitude on service life of the device. The principle of the document is that the electrical loss is input into a thermal model, the thermal impedance curve is used to obtain the temperature response, and the service life is estimated according to the temperature cycle amplitude. The method has the characteristics of clear structure and simple modeling, and can be used for predicting the junction temperature of the IGBT under the general working condition. However, the prior art still has the limitation that the coupling literature of thermal-mechanical stress and material fatigue mechanism is not considered, the service life is estimated only by relying on the temperature cycle amplitude delta T, and the mechanical stress and strain accumulation of a welding layer, a chip and a bonding wire are not calculated, so that the real fatigue damage inside the package cannot be accurately reflected. The current, duty cycle, cooling effect of IGBTs in real-world applications where the change of the device operating parameters with time (such as current aging, duty cycle drift, cooling performance degradation) is not considered can degrade year by year, but the literature does not give any age-related dynamic degradation model, so life prediction is optimistic. The Arrhenius temperature acceleration effect (chemical aging) literature is not considered, and the "temperature activated aging mechanism" such as chemical diffusion and bonding wire fatigue is not contained, so that the service life shortening phenomenon under the long-term high-temperature condition cannot be reflected. In addition, most of the existing researches only pay attention to damage accumulation in an operation state, neglect static aging of the IGBT caused by temperature and time in a non-operation (such as storage and standby) state, and cause systematic deviation in full life cycle life assessment. Therefore, a high-precision IGBT life prediction method capable of integrating multiple physical fields and multiple failure mechanisms and distinguishing between an operating state and a non-operating state is needed to improve life assessment accuracy and engineering practicability in high-reliability applications such as new energy automobiles, photovoltaic inversion, industrial frequency conversion and the like. Disclosure of Invention Aiming at the existing IGBT life prediction technology based on electric-thermal coupling, the fatigue life is usually estimated only through junction temperature fluctuation delta T, and the true failure mechanism of the IGBT in long-term operation cannot be accurately described. The method has the specific problems that thermal mechanical stress and material strain caused by temperature circulation are not considered, service life calculation deviation is large, parameter degradation