CN-121997644-A - Periodic temperature fluctuation distribution calculation method, system, medium and equipment

CN121997644ACN 121997644 ACN121997644 ACN 121997644ACN-121997644-A

Abstract

A method for calculating periodic temperature fluctuation distribution of an IGBT module, a system, a medium and equipment are provided, wherein the method comprises the steps of establishing a frequency domain finite element thermal model according to an actual three-dimensional geometrical structure and material characteristics of the IGBT module, describing a heat transfer relation between the IGBT module and a radiator by adopting Robin boundary conditions under boundary conditions, establishing a frequency domain loss model of the IGBT module, obtaining a frequency domain expression of the periodic loss by modeling conduction loss and switching loss of an IGBT chip and an FWD chip through Fourier transformation, executing an iterative calculation process, solving a steady-state heat conduction equation based on the average loss, obtaining the average temperature distribution to be substituted into the frequency domain loss model as a reference temperature, solving temperature fluctuation responses corresponding to all orders of harmonic waves in the frequency domain to obtain amplitude values and phase angles of all the temperature fluctuation, and converting temperature responses in the frequency domain into the periodic steady-state temperature fluctuation distribution in the time domain through frequency-domain transformation.

Inventors

ZHU LINGYU
WANG WEICHENG
TANG YIZHENG
XU HONGHAI
JI XUEJUN
CHENG YUELIANG
TANG HAINING
ZHANG TAO
SHENTU LEIXUAN

Assignees

西安交通大学
国电南瑞科技股份有限公司
国网浙江省电力有限公司电力科学研究院

Dates

Publication Date: 20260508
Application Date: 20251231

Claims (10)

1. The periodic temperature fluctuation distribution calculation method of the IGBT module is characterized by comprising the following steps of: Step 1, a frequency domain finite element thermal model is established according to the actual three-dimensional geometric structure and material characteristics of an IGBT module, a control equation of the frequency domain finite element thermal model is a steady-state heat conduction equation in a frequency domain form, and a Robin boundary condition is adopted as a boundary condition to describe a heat transfer relation between the IGBT module and a radiator; Step 2, establishing a frequency domain loss model of the IGBT module, wherein the total loss of the IGBT chip and the FWD chip is the sum of the conduction loss and the switching loss through modeling the conduction loss and the switching loss of the IGBT chip, and obtaining a frequency domain expression of periodic loss by utilizing Fourier transformation, wherein the frequency domain expression comprises average loss, amplitude of each subharmonic loss and phase angle; and step 3, executing an iterative calculation process, wherein a steady-state heat conduction equation is solved based on the average loss, average temperature distribution is obtained and is substituted into a frequency domain loss model as reference temperature, temperature fluctuation responses corresponding to all orders of harmonic waves are solved in a frequency domain to obtain amplitude values and phase angles of all times of temperature fluctuation, and the temperature responses in the frequency domain are converted into periodic steady-state temperature fluctuation distribution in the time domain through frequency-time domain transformation.
2. The method for calculating the periodic temperature fluctuation distribution of the IGBT module according to claim 1, wherein the steady-state heat conduction equation is preferably: where ρ is density, c is specific heat capacity, λ is thermal conductivity, ω is frequency, T is temperature, i is imaginary unit, xyz is coordinate Φ s is heat source.
3. The method for calculating the periodic temperature fluctuation distribution of the IGBT module according to claim 1, wherein the boundary condition describes a heat transfer relationship between the IGBT module and the heat sink using a Robin boundary condition as: H is the equivalent heat exchange coefficient, and T ref is the radiator temperature.
4. The method for calculating the periodic temperature fluctuation distribution of the IGBT module according to claim 1, wherein the conduction losses of the IGBT chip and the FWD chip are as follows, ; Where v ce , v F is the turn-on voltage of the IGBT and FWD, respectively, i T , i D is the current flowing through the IGBT and FWD, and M T , M D is the duty cycle, which is defined as follows: ; Where m is the modulation ratio, ω 0 is the angular frequency, The switching loss is: ; Where f sw is the equivalent switching frequency, V C is the average capacitance voltage of the submodule, K v is the voltage correction coefficient, uref is the reference voltage, The total loss of the chip is the sum of the conduction loss and the switching loss: 。
5. The method for calculating the periodic temperature fluctuation distribution of the IGBT module according to claim 4, wherein the total loss expression in the frequency domain form: ; ; Where P total is the instantaneous loss, P 0 is the average loss, P k is the magnitude of the k losses, phi k is the phase angle of the k losses, and a k and b k can be found by: 。
6. The method for calculating the periodic temperature fluctuation distribution of the IGBT module according to claim 1, wherein the periodic steady-state temperature fluctuation distribution is ; Where T 0 is the average temperature, T k is the magnitude of the kth temperature fluctuation, φ k is the phase angle of the kth power loss, and θ k is the phase angle of the kth temperature response due to heat conduction.
7. The method for calculating the periodic temperature fluctuation distribution of the IGBT module according to claim 1, wherein the average temperature does not change with the instantaneous temperature change in solving the harmonic temperature response in the frequency domain.
8. A system for carrying out the method of any one of claims 1-7, comprising: The geometric modeling module is used for constructing a three-dimensional geometric model of the IGBT module; the material parameter setting module is used for inputting the heat conductivity, specific heat capacity and density of each layer of material; the frequency domain thermal model construction module is used for establishing a frequency domain finite element thermal conduction model and applying boundary conditions; the frequency domain loss calculation module is used for calculating the periodic loss of the IGBT and the FWD according to the operation condition and carrying out Fourier decomposition; the iteration solving module is used for sequentially solving the average temperature field and the frequency domain harmonic temperature response; and the time domain reconstruction module is used for generating a final periodical steady-state temperature fluctuation distribution result through frequency-time domain transformation.
9. A computer storage medium comprising computer instructions which, when run on a computer, cause the computer to perform the method of any of claims 1-7.
10. An electronic device, the electronic device comprising: A memory, a processor, and a computer program stored on the memory and executable on the processor, wherein, The processor, when executing the program, implements the method of any one of claims 1-7.

Description

Periodic temperature fluctuation distribution calculation method, system, medium and equipment Technical Field The invention relates to the technical field of IGBT module detection, in particular to a method, a system, a medium and equipment for calculating periodic temperature fluctuation distribution of an IGBT module. Background The IGBT module is a core device of power electronic equipment such as a fan converter, a photovoltaic inverter, a flexible direct-current transmission converter valve and the like, and the reliability of the IGBT module directly influences the safe and stable operation of the power electronic equipment. Periodic temperature fluctuation in the long-term operation process is a main reason for degradation of the IGBT module, so that efficient calculation of the periodic temperature fluctuation distribution of the IGBT module is a key for reliability evaluation of the IGBT module. The above information disclosed in the background section is only for enhancement of understanding of the background of the invention and therefore may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Disclosure of Invention The invention provides a method, a system, a medium and equipment for calculating periodic temperature fluctuation distribution of an IGBT module, which can rapidly and efficiently obtain the periodic temperature fluctuation distribution of the IGBT module. The method for calculating the periodic temperature fluctuation distribution of the IGBT module comprises the following steps: Step 1, a frequency domain finite element thermal model is established according to the actual three-dimensional geometric structure and material characteristics of an IGBT module, a control equation of the frequency domain finite element thermal model is a steady-state heat conduction equation in a frequency domain form, and a Robin boundary condition is adopted as a boundary condition to describe a heat transfer relation between the IGBT module and a radiator; Step 2, establishing a frequency domain loss model of the IGBT module, wherein the total loss of the IGBT chip and the FWD chip is the sum of the conduction loss and the switching loss through modeling the conduction loss and the switching loss of the IGBT chip, and obtaining a frequency domain expression of periodic loss by utilizing Fourier transformation, wherein the frequency domain expression comprises average loss, amplitude of each subharmonic loss and phase angle; and step 3, executing an iterative calculation process, wherein a steady-state heat conduction equation is solved based on the average loss, average temperature distribution is obtained and is substituted into a frequency domain loss model as reference temperature, temperature fluctuation responses corresponding to all orders of harmonic waves are solved in a frequency domain to obtain amplitude values and phase angles of all times of temperature fluctuation, and the temperature responses in the frequency domain are converted into periodic steady-state temperature fluctuation distribution in the time domain through frequency-time domain transformation. In the method for calculating the periodic temperature fluctuation distribution of the IGBT module, a steady-state heat conduction equation is as follows: Where ρ is density, c is specific heat capacity, λ is thermal conductivity, ω is frequency, T is temperature, i is imaginary unit, xyz is coordinate Φ s is heat source. In the method for calculating the periodic temperature fluctuation distribution of the IGBT module, the boundary condition adopts Robin boundary condition to describe the heat transfer relationship between the IGBT module and the radiator, and the heat transfer relationship is as follows: H is the equivalent heat exchange coefficient, and T ref is the radiator temperature. In the method for calculating the periodic temperature fluctuation distribution of the IGBT module, the conduction loss of the IGBT chip and the FWD chip is as follows, Where v ce, vF is the turn-on voltage of the IGBT and FWD, respectively, i T, iD is the current flowing through the IGBT and FWD, and M T, MD is the duty cycle, which is defined as follows: Where m is the modulation ratio, ω 0 is the angular frequency, The switching loss is: Where f sw is the equivalent switching frequency, V C is the average capacitance voltage of the submodule, K v is the voltage correction coefficient, uref is the reference voltage, The total loss of the chip is the sum of the conduction loss and the switching loss: 。 In the method for calculating the periodic temperature fluctuation distribution of the IGBT module, the total loss expression in the frequency domain form is as follows: Where P total is the instantaneous loss, P 0 is the average loss, P k is the magnitude of the k losses, phi k is the phase angle of the k losses, and a k and b k can be found by: 。 In the method for calculating th