Online temperature monitoring of IGBTs is a crucial means to enhance the reliability of high-power converters.In the existing thermal model methods,the junction temperature is derived through the device power loss,whi...Online temperature monitoring of IGBTs is a crucial means to enhance the reliability of high-power converters.In the existing thermal model methods,the junction temperature is derived through the device power loss,which is difficult to obtain accurately in real time.This paper proposes a power loss observer to estimate the real-time power loss accurately.Unlike conventional methods,the proposed method only needs measure the heatsink temperature.Moreover,the proposed technique is robust to disturbances such as wind speed fluctuations,solder aging,and temperature dependence of thermal parameters,which helps to improve the temperature estimation accuracy throughout the full life cycle of IGBT modules.This paper analyzes the proposed method’s mathematical principle,algorithm,and implementation steps,while the loss observer is validated by simulation and experiment.展开更多
In power electronics applications,the selection of condition monitoring methods significantly affects both the precision and complexity of the junction temperature evaluation,which is essential for the reliability ass...In power electronics applications,the selection of condition monitoring methods significantly affects both the precision and complexity of the junction temperature evaluation,which is essential for the reliability assessment of power semiconductor devices.This study begins with a failure mechanism analysis of state-of-the-art power semiconductor devices.Junction temperature measurement methods can be categorized into three distinct approaches:thermal image-based,thermal model-based,and temperature-sensitive electrical parameter(TSEP)-based methods.Their respective advantages and disadvantages are comprehensively compared.Moreover,condition monitoring of the ON-state voltage drop is summarized and benchmarked.ON-state voltage and junction temperature measurements are experimentally demonstrated in a standard three-phase converter,which provides superior measurement accuracy and rapid dynamic response characteristics.Additionally,this investigation is extended to measurement methods for TSEP in wide-bandgap semiconductors.展开更多
Compared to Si devices,the junction temperature of SiC devices is more critical due to the reliability concern introduced by immature packaging technology applied to new material.This paper proposes a practical SiC MO...Compared to Si devices,the junction temperature of SiC devices is more critical due to the reliability concern introduced by immature packaging technology applied to new material.This paper proposes a practical SiC MOSFET junction temperature monitoring method based on the on-state voltage$\\boldsymbol{V}_{\\mathbf{ds}(\\mathbf{on})}$measurement.In Section II of the paper,the temperature sensitivity of the on-state voltage$\\boldsymbol{V}_{\\mathbf{ds}(\\mathbf{on})}$is characterized.The hardware of the measurement system is set up in Section III,which consists of an On-state Voltage Measurement Circuit(OVMC),the sampling and isolation circuit.Next,a calibration method based on the self-heating of the SiC MOSFET chip is presented in Section IV.In the final Section,the junction temperature is monitored synchronously according to the calibration results.The proposed method is applied to a Buck converter and verified by both an Infrared Radiation(IR)camera and a Finite Element Analysis(FEA)tool.展开更多
The authors have developed a large-signal simulation technique extending an in-house small-signal simulation code for analyzing a 94 GHz double-drift region impact avalanche transit time device based on silicon with a...The authors have developed a large-signal simulation technique extending an in-house small-signal simulation code for analyzing a 94 GHz double-drift region impact avalanche transit time device based on silicon with a non-sinusoidal voltage excitation and studied the effect of junction temperature between 300 and 550 K on the large-signal characteristics of the device for both continuous wave （CW） and pulsed modes of operation. Results show that the large-signal RF power output of the device in both CW and pulsed modes increases with the increase of voltage modulation factor up to 60%, but decreases sharply with further increase of voltage modulation factor for a particular junction temperature; while the same parameter increases with the increase of junction temperature for a particular voltage modulation factor. Heat sinks made of copper and type-IIA diamond are designed to carry out the steady-state and transient thermal analysis of the device operating in CW and pulsed modes respectively. Authors have adopted Olson＇s method to carry out the transient analysis of the device, which clearly establishes the superiority of type-IIA diamond over copper as the heat sink material of the device from the standpoint of the undesirable effect of frequency chirping due to thermal transients in the pulsed mode.展开更多
A junction temperature monitoring method has been presented based on the on-state voltage at high currents.With a simplified physical model,this method mapped the relationship between junction temperature and on-state...A junction temperature monitoring method has been presented based on the on-state voltage at high currents.With a simplified physical model,this method mapped the relationship between junction temperature and on-state voltage.The tough calibration and signal sensing issues are solved.Verified by body-diode voltage detecting method,the presented method shows a good performance and high accuracy,in the meantime,it would not change the modulation strategy and topology of the converter.展开更多
The aim of this study is to achieve online monitoring of the junction temperature of double-sided-cooling insulated gate bipolar transistor(IGBT)power modules by using the on-state voltage under a high current to maxi...The aim of this study is to achieve online monitoring of the junction temperature of double-sided-cooling insulated gate bipolar transistor(IGBT)power modules by using the on-state voltage under a high current to maximize the utilization of IGBT power chips.Online junction temperature measurement plays an important role in improving the reliability of the inverter with IGBT,increasing the power density of the motor controller of electric vehicles,and reducing the cost of electric vehicles.展开更多
It has been a scientific and technological problem in the field of microelectronics for several decades that the electrical method is used to measure the peak junction temperature of power transistors. Based on the ex...It has been a scientific and technological problem in the field of microelectronics for several decades that the electrical method is used to measure the peak junction temperature of power transistors. Based on the excessive thermotaxis effect of low current, a novel electrical measurement method of the peak junction temperature is presented in this paper. The method is called the thermal spectrum analysis method of transistors, simply designated TSA （thermal spectrum analysis method）. Unlike the common method which uses a single measuring current, TSA uses multi-step currents to measure temperature-sensitive parameters. Based on the excessive thermotaxis effect of low current and the sub-transistor parallel model, the peak junction temperature and non-uniform property of junction temperature distribution are analyzed successfully.展开更多
Junction temperature of alternating current light-emitting-diode （AC-LED） has a significant effect on its stable light output and lifetime. The threshold voltage measurement is employed to characterize the junction ...Junction temperature of alternating current light-emitting-diode （AC-LED） has a significant effect on its stable light output and lifetime. The threshold voltage measurement is employed to characterize the junction temperature of AC-LED, due to its excellent merits in high efficiency and accuracy. The threshold voltage is measured when the driving current of an AC-LED rises to a reference on-set value from the zero-crossing node. Based on multiple measurements of threshold voltage at different temperatures, a linear relationship was uncovered between the threshold voltage and the junction temperature of AC- LED with the correlating factor of temperature sensitive parameter （TSP）. Thereby, we can calculate the junction temperature with the TSP and threshold voltage once the AC-LED stays at thermal equilibrium state. The accuracy of the proposed junction temperature measurement technique was found to be ＋3.2℃ for the reference current of 1 mA. It is concluded that the method of threshold voltage is accurate and simple to implement, making it highly suitable for measuring the junction temperature of AC-LED in industry.展开更多
The power module of the Insulated Gate Bipolar Transistor(IGBT)is the core component of the traction transmission system of high-speed trains.The module's junction temperature is a critical factor in determining d...The power module of the Insulated Gate Bipolar Transistor(IGBT)is the core component of the traction transmission system of high-speed trains.The module's junction temperature is a critical factor in determining device reliability.Existing temperature monitoring methods based on the electro-thermal coupling model have limitations,such as ignoring device interactions and high computational complexity.To address these issues,an analysis of the parameters influencing IGBT failure is conducted,and a temperature monitoring method based on the Macro-Micro Attention Long Short-Term Memory(MMALSTM)recursive neural network is proposed,which takes the forward voltage drop and collector current as features.Compared with the traditional electricalthermal coupling model method,it requires fewer monitoring parameters and eliminates the complex loss calculation and equivalent thermal resistance network establishment process.The simulation model of a highspeed train traction system has been established to explore the accuracy and efficiency of MMALSTM-based prediction methods for IGBT power module junction temperature.The simulation outcomes,which deviate only 3.2% from the theoretical calculation results of the electric-thermal coupling model,confirm the reliability of this approach for predicting the temperature of IGBT power modules.展开更多
Insulated gate bipolar transistor(IGBT)modules are widely employed in high-power conversion systems.Their junction temperature ranks as one of the most important factors in the reliability of power semiconductor devic...Insulated gate bipolar transistor(IGBT)modules are widely employed in high-power conversion systems.Their junction temperature ranks as one of the most important factors in the reliability of power semiconductor devices.Thermo-sensitive electrical parameter(TSEP)is regarded as the promising solution to extract the junction temperature due to its non-invasion measurement,fast response and high accuracy.However,accurate collector current measurement is required if only the individual TSEP is adopted,which increases the complexity and cost.In this paper,the combined TSEP method is proposed to eliminate the influence of collector current(/c),where the turn-off delay time(tdoff)and maximum decrease rate of/c(max d/c/dt)are adopted and combined.The two TSEPs both have linear relationships withjunction temperature and/c.When they are combined mathematically,the influence of/c is eliminated.Experiments have been implemented to validate the effectiveness of the proposed approach.The comparison between combined TSEP and two individual TSEP methods are illustrated and analyzed.展开更多
The Insulated-Gate Bipolar Transistor(IGBT)module is the core of the three-level(3L)traction converter.In order to improve the lifetime of the traction converter,a model predictive torque control(MPTC)based on the jun...The Insulated-Gate Bipolar Transistor(IGBT)module is the core of the three-level(3L)traction converter.In order to improve the lifetime of the traction converter,a model predictive torque control(MPTC)based on the junction temperature constraint is proposed.Firstly,the optimization range is reduced by judging the sector where the reference voltage vector locates,as the traditional MPTC needs to be optimized 27 times in each sampling period,which requires a large amount of calculation.Secondly,by simplifying the calculation of IGBT power loss and dynamically constraining it in the cost function,the performance of optimal voltage vector balancing control can be balanced with power loss.Simulation results show that the proposed method reduces the junction temperature of the power semiconductor and prolongs the converter lifetime compared with the traditional strategy.展开更多
With the rapid development of the world economy,IGBT has been widely used in motor drive and electric energy conversion.In order to timely detect the fatigue damage of IGBT,it is necessary to monitor the junction temp...With the rapid development of the world economy,IGBT has been widely used in motor drive and electric energy conversion.In order to timely detect the fatigue damage of IGBT,it is necessary to monitor the junction temperature of IGBT.In order to realize the fast calculation of IGBT junction temperature,a finite element method of IGBT temperature field reduction is proposed in this paper.Firstly,the finite element calculation process of IGBT temperature field is introduced and the linear equations of finite element calculation of temperature field are derived.Temperature field data of different working conditions are obtained by finite element simulation to form the sample space.Then the covariance matrix of the sample space is constructed,whose proper orthogonal decomposition and modal extraction are carried out.Reasonable basis vector space is selected to complete the low dimensional expression of temperature vector inside and outside the sample space.Finally,the reduced-order model of temperature field finite element is obtained and solved.The results of the reduced order model are compared with those of the finite element method,and the performance of the reduced-order model is evaluated from two aspects of accuracy and rapidity.展开更多
There are challenges to the reliability evaluation for insulated gate bipolar transistors(IGBT)on electric vehicles,such as junction temperature measurement,computational and storage resources.In this paper,a junction...There are challenges to the reliability evaluation for insulated gate bipolar transistors(IGBT)on electric vehicles,such as junction temperature measurement,computational and storage resources.In this paper,a junction temperature estimation approach based on neural network without additional cost is proposed and the lifetime calculation for IGBT using electric vehicle big data is performed.The direct current(DC)voltage,operation current,switching frequency,negative thermal coefficient thermistor(NTC)temperature and IGBT lifetime are inputs.And the junction temperature(T_(j))is output.With the rain flow counting method,the classified irregular temperatures are brought into the life model for the failure cycles.The fatigue accumulation method is then used to calculate the IGBT lifetime.To solve the limited computational and storage resources of electric vehicle controllers,the operation of IGBT lifetime calculation is running on a big data platform.The lifetime is then transmitted wirelessly to electric vehicles as input for neural network.Thus the junction temperature of IGBT under long-term operating conditions can be accurately estimated.A test platform of the motor controller combined with the vehicle big data server is built for the IGBT accelerated aging test.Subsequently,the IGBT lifetime predictions are derived from the junction temperature estimation by the neural network method and the thermal network method.The experiment shows that the lifetime prediction based on a neural network with big data demonstrates a higher accuracy than that of the thermal network,which improves the reliability evaluation of system.展开更多
Excessive temperature rise during the operation of the generator system can affect the safety and life cycle of the machine.Therefore,in order to accurately obtain the internal temperature of the switched reluctance g...Excessive temperature rise during the operation of the generator system can affect the safety and life cycle of the machine.Therefore,in order to accurately obtain the internal temperature of the switched reluctance generator(SRG),an internal temperature estimation model based on electric heating is established in this paper.First,an im-proved variable coefficient Bertotti loss separation calcula-tion formula is adopted to solve the iron loss of the genera-tor under various operating conditions.Subsequently,the accurate heat source parameters in the temperature model can be obtained,and the corresponding heat source data can be calculated.Then,based on the obtained heat source data,an equivalent thermal circuit model is established for SRG.Meanwhile,in order to effectively reduce the internal temperature during SRG operation,a new water-cooled structure for direct cooling of SRG stator windings is pro-posed in this paper,which can effectively reduce the tem-perature rise during operation,thus improving the reliabil-ity of the generator.Finally,by comparing the equivalent thermal circuit model,finite element thermal model,and experimental temperature measurements of SRG,it is found that results from the equivalent thermal circuit model of the SRG are closer to the measured temperatures,while the effectiveness of the water-cooled structure is verified.展开更多
By integrating a temperature-adaptive function, an active gate driver (AGD) enhances the switching performance of silicon carbide (SiC) MOSFETs under varying temperature conditions. However, the lack of analytical exp...By integrating a temperature-adaptive function, an active gate driver (AGD) enhances the switching performance of silicon carbide (SiC) MOSFETs under varying temperature conditions. However, the lack of analytical expressions describing the coupling between AGD parameters and temperature variation limits the broader application of this method, particularly in SiC modules that exhibit complicated device transient behaviors. To address this challenge, a mathematical model of the transient behavior of an SiC module is developed to investigate the relationship among AGD parameters, junction temperature, and switching performance. The analysis reveals that the impact of temperature on switching performance is directly linked to the duration of each gate resistance. Accordingly, a temperature-adaptive AGD for SiC MOSFET modules is proposed. Online junction temperature monitoring is achieved using turn-on delay detection, and the duration of each gate’s driving resistance is dynamically adjusted. The proposed temperature-adaptive AGD is validated experimentally using a commercial 1.2 kV/560 A SiC MOSFET at 600 V/200 A. Experimental results across a temperature range of 20 ℃ to 100 ℃ demonstrate that electrical stress variation remains within 15%, while loss variation does not exceed 10%.展开更多
In order to study the role of printed circuit board(PCB)in high-power LED heat dissipation,a simple model of high-power LED lamp was designed.According to this lamp model,some thermal performances such as thermal resi...In order to study the role of printed circuit board(PCB)in high-power LED heat dissipation,a simple model of high-power LED lamp was designed.According to this lamp model,some thermal performances such as thermal resistances of four types of PCB and the changes of LED junction temperature were tested under three different working currents.The obtained results indicate that LED junction temperature can not be lowered significantly with the decreasing thermal resistance of PCB.However,PCB with low thermal resistance can be matched with smaller volume heat sink,so it is hopeful to reduce the size,weight and cost of LED lamp.展开更多
Thermal management of LED junction temperature is one of the fundamental technologies for LED lamp to ensure basic specifications in many aspects. Analysed is the high power LED's distribution on heat sink. Using ...Thermal management of LED junction temperature is one of the fundamental technologies for LED lamp to ensure basic specifications in many aspects. Analysed is the high power LED's distribution on heat sink. Using mathematical statistical methods, a formula is conlcuded to calculate the size of heat sink under LED safe working temperature, which provides a method to researchers and LED lamp manufacturers.展开更多
The insulated gate bipolar transistor(IGBT)module is one of the most age-affected components in the switch power supply, and its reliability prediction is conducive to timely troubleshooting and reduction in safety ri...The insulated gate bipolar transistor(IGBT)module is one of the most age-affected components in the switch power supply, and its reliability prediction is conducive to timely troubleshooting and reduction in safety risks and unnecessary costs. The pulsed current pattern of the accelerator power supply is different from other converter applications;therefore, this study proposed a lifetime estimation method for IGBT modules in pulsed power supplies for accelerator magnets. The proposed methodology was based on junction temperature calculations using square-wave loss discretization and thermal modeling.Comparison results showed that the junction temperature error between the simulation and IR measurements was less than 3%. An AC power cycling test under real pulsed power supply applications was performed via offline wearout monitoring of the tested power IGBT module. After combining the IGBT4 PC curve and fitting the test results,a simple corrected lifetime model was developed to quantitatively evaluate the lifetime of the IGBT module,which can be employed for the accelerator pulsed power supply in engineering. This method can be applied to other IGBT modules and pulsed power supplies.展开更多
Boron-doped aluminum nitride （B-AlN） thin films were synthesized on Al substrates by using chemical vapor deposition method by changing the synthesis parameters and were used as thermal interface material for high p...Boron-doped aluminum nitride （B-AlN） thin films were synthesized on Al substrates by using chemical vapor deposition method by changing the synthesis parameters and were used as thermal interface material for high power light emitting diode （LED）. The B-AlN thin film-coated Al substrate was used as heat sink and studied the performance of high power LED at various driving currents. The recorded transient cooling curve was evaluated to study the rise in junction temperature （Tj）, total thermal resistance （gth_tot） and the substrate thermal resistance （Rth_sub） of the given LED. From the results, the B-AlN thin film （prepared at process 4） interfaced LED showed low Rth-tot and Tj value for all driving currents and observed high difference in Rth_tot （△Rth_tot =2.2 K/W） at 700 mA when compared with the Rth-tot of LED attached on bare Al substrates （LED/Al）. The Tj of LED was reduced considerably and observed 4.7 ℃ as ATj for the film prepared using process 4 condition when compared with LED/Al boundary condition at 700 mA. The optical performance of LED was also tested for all boundary conditions and showed improved lux values for the given LED at 700 mA where B-AlN thin film was synthesized using optimized flow of Al, B and N sources with minimized B and N content. The other optical parameters such as color correlated temperature and color rendering index were also measured and observed low difference for all boundary conditions. The observed results are suggested to use B-AlN thin film as efficient solid thin film thermal interface materials in high power LED.展开更多
In this paper,high-power LED with many integrated chips is used as thermal resistance analysis research object, and we do thermal resistance testing technology research on it. We put forward the thermocouple point con...In this paper,high-power LED with many integrated chips is used as thermal resistance analysis research object, and we do thermal resistance testing technology research on it. We put forward the thermocouple point contact test method. According to the principle that LED forward voltage changes with temperature,LED heat sink to surface temperature distribution is studied directly in the test,and then we analyze the thermal resistance of high-power LED with many integrated chips when its secondary packaging is introduced. This method makes the measurement of thermal resistance of LED more rapid and convenient. It provides an effective assessment method for the analysis of high power LED device design and engineering application.展开更多
基金supported by the National Key Research and Development Program of China(No.2022YFE 0138400)the National Nature Science Foundation of China(No.51925702)Zhejiang Provincial Key R&D Program Project(No.2023C01061).
文摘Online temperature monitoring of IGBTs is a crucial means to enhance the reliability of high-power converters.In the existing thermal model methods,the junction temperature is derived through the device power loss,which is difficult to obtain accurately in real time.This paper proposes a power loss observer to estimate the real-time power loss accurately.Unlike conventional methods,the proposed method only needs measure the heatsink temperature.Moreover,the proposed technique is robust to disturbances such as wind speed fluctuations,solder aging,and temperature dependence of thermal parameters,which helps to improve the temperature estimation accuracy throughout the full life cycle of IGBT modules.This paper analyzes the proposed method’s mathematical principle,algorithm,and implementation steps,while the loss observer is validated by simulation and experiment.
文摘In power electronics applications,the selection of condition monitoring methods significantly affects both the precision and complexity of the junction temperature evaluation,which is essential for the reliability assessment of power semiconductor devices.This study begins with a failure mechanism analysis of state-of-the-art power semiconductor devices.Junction temperature measurement methods can be categorized into three distinct approaches:thermal image-based,thermal model-based,and temperature-sensitive electrical parameter(TSEP)-based methods.Their respective advantages and disadvantages are comprehensively compared.Moreover,condition monitoring of the ON-state voltage drop is summarized and benchmarked.ON-state voltage and junction temperature measurements are experimentally demonstrated in a standard three-phase converter,which provides superior measurement accuracy and rapid dynamic response characteristics.Additionally,this investigation is extended to measurement methods for TSEP in wide-bandgap semiconductors.
基金supported by the National Key R&D Program of China(2016YFB0100600)the Key Program of Bureau of Frontier Sciences and Education,Chinese Academy of Sciences(QYZDBSSW-JSC044)。
文摘Compared to Si devices,the junction temperature of SiC devices is more critical due to the reliability concern introduced by immature packaging technology applied to new material.This paper proposes a practical SiC MOSFET junction temperature monitoring method based on the on-state voltage$\\boldsymbol{V}_{\\mathbf{ds}(\\mathbf{on})}$measurement.In Section II of the paper,the temperature sensitivity of the on-state voltage$\\boldsymbol{V}_{\\mathbf{ds}(\\mathbf{on})}$is characterized.The hardware of the measurement system is set up in Section III,which consists of an On-state Voltage Measurement Circuit(OVMC),the sampling and isolation circuit.Next,a calibration method based on the self-heating of the SiC MOSFET chip is presented in Section IV.In the final Section,the junction temperature is monitored synchronously according to the calibration results.The proposed method is applied to a Buck converter and verified by both an Infrared Radiation(IR)camera and a Finite Element Analysis(FEA)tool.
文摘The authors have developed a large-signal simulation technique extending an in-house small-signal simulation code for analyzing a 94 GHz double-drift region impact avalanche transit time device based on silicon with a non-sinusoidal voltage excitation and studied the effect of junction temperature between 300 and 550 K on the large-signal characteristics of the device for both continuous wave （CW） and pulsed modes of operation. Results show that the large-signal RF power output of the device in both CW and pulsed modes increases with the increase of voltage modulation factor up to 60%, but decreases sharply with further increase of voltage modulation factor for a particular junction temperature; while the same parameter increases with the increase of junction temperature for a particular voltage modulation factor. Heat sinks made of copper and type-IIA diamond are designed to carry out the steady-state and transient thermal analysis of the device operating in CW and pulsed modes respectively. Authors have adopted Olson＇s method to carry out the transient analysis of the device, which clearly establishes the superiority of type-IIA diamond over copper as the heat sink material of the device from the standpoint of the undesirable effect of frequency chirping due to thermal transients in the pulsed mode.
基金Supported by the National Key Research and Development Program of China(2016YFB0100600)the Key Program of Bureau of Frontier Sciences and Education,Chinese Academy of Sciences(QYZDBSSW-JSC044).
文摘A junction temperature monitoring method has been presented based on the on-state voltage at high currents.With a simplified physical model,this method mapped the relationship between junction temperature and on-state voltage.The tough calibration and signal sensing issues are solved.Verified by body-diode voltage detecting method,the presented method shows a good performance and high accuracy,in the meantime,it would not change the modulation strategy and topology of the converter.
基金Supported by the National Key Research and Development Program of China(2016YFB0100600).
文摘The aim of this study is to achieve online monitoring of the junction temperature of double-sided-cooling insulated gate bipolar transistor(IGBT)power modules by using the on-state voltage under a high current to maximize the utilization of IGBT power chips.Online junction temperature measurement plays an important role in improving the reliability of the inverter with IGBT,increasing the power density of the motor controller of electric vehicles,and reducing the cost of electric vehicles.
基金Project supported by the National Natural Science Foundation of China (No.60476039)the Director Foundation of Institute of Microelectronics of Chinese Academy of Sciences (No.5408SA011001)
文摘It has been a scientific and technological problem in the field of microelectronics for several decades that the electrical method is used to measure the peak junction temperature of power transistors. Based on the excessive thermotaxis effect of low current, a novel electrical measurement method of the peak junction temperature is presented in this paper. The method is called the thermal spectrum analysis method of transistors, simply designated TSA （thermal spectrum analysis method）. Unlike the common method which uses a single measuring current, TSA uses multi-step currents to measure temperature-sensitive parameters. Based on the excessive thermotaxis effect of low current and the sub-transistor parallel model, the peak junction temperature and non-uniform property of junction temperature distribution are analyzed successfully.
文摘Junction temperature of alternating current light-emitting-diode （AC-LED） has a significant effect on its stable light output and lifetime. The threshold voltage measurement is employed to characterize the junction temperature of AC-LED, due to its excellent merits in high efficiency and accuracy. The threshold voltage is measured when the driving current of an AC-LED rises to a reference on-set value from the zero-crossing node. Based on multiple measurements of threshold voltage at different temperatures, a linear relationship was uncovered between the threshold voltage and the junction temperature of AC- LED with the correlating factor of temperature sensitive parameter （TSP）. Thereby, we can calculate the junction temperature with the TSP and threshold voltage once the AC-LED stays at thermal equilibrium state. The accuracy of the proposed junction temperature measurement technique was found to be ＋3.2℃ for the reference current of 1 mA. It is concluded that the method of threshold voltage is accurate and simple to implement, making it highly suitable for measuring the junction temperature of AC-LED in industry.
基金supported by the Science and Technology Project of the Headquarters of the State Grid Corporation of China(52199922001U).
文摘The power module of the Insulated Gate Bipolar Transistor(IGBT)is the core component of the traction transmission system of high-speed trains.The module's junction temperature is a critical factor in determining device reliability.Existing temperature monitoring methods based on the electro-thermal coupling model have limitations,such as ignoring device interactions and high computational complexity.To address these issues,an analysis of the parameters influencing IGBT failure is conducted,and a temperature monitoring method based on the Macro-Micro Attention Long Short-Term Memory(MMALSTM)recursive neural network is proposed,which takes the forward voltage drop and collector current as features.Compared with the traditional electricalthermal coupling model method,it requires fewer monitoring parameters and eliminates the complex loss calculation and equivalent thermal resistance network establishment process.The simulation model of a highspeed train traction system has been established to explore the accuracy and efficiency of MMALSTM-based prediction methods for IGBT power module junction temperature.The simulation outcomes,which deviate only 3.2% from the theoretical calculation results of the electric-thermal coupling model,confirm the reliability of this approach for predicting the temperature of IGBT power modules.
基金the National Nature Science Foundations of China(51490682,51677166).
文摘Insulated gate bipolar transistor(IGBT)modules are widely employed in high-power conversion systems.Their junction temperature ranks as one of the most important factors in the reliability of power semiconductor devices.Thermo-sensitive electrical parameter(TSEP)is regarded as the promising solution to extract the junction temperature due to its non-invasion measurement,fast response and high accuracy.However,accurate collector current measurement is required if only the individual TSEP is adopted,which increases the complexity and cost.In this paper,the combined TSEP method is proposed to eliminate the influence of collector current(/c),where the turn-off delay time(tdoff)and maximum decrease rate of/c(max d/c/dt)are adopted and combined.The two TSEPs both have linear relationships withjunction temperature and/c.When they are combined mathematically,the influence of/c is eliminated.Experiments have been implemented to validate the effectiveness of the proposed approach.The comparison between combined TSEP and two individual TSEP methods are illustrated and analyzed.
基金supported by the following funding:Hunan Provincial Department of Education Outstanding Youth Project(Grant No.24B0025)Regional Joint Fund Project of Hunan Province(Grant No.2025JJ70036)National Natural Science Foundation of China(Grant No.52002409).
文摘The Insulated-Gate Bipolar Transistor(IGBT)module is the core of the three-level(3L)traction converter.In order to improve the lifetime of the traction converter,a model predictive torque control(MPTC)based on the junction temperature constraint is proposed.Firstly,the optimization range is reduced by judging the sector where the reference voltage vector locates,as the traditional MPTC needs to be optimized 27 times in each sampling period,which requires a large amount of calculation.Secondly,by simplifying the calculation of IGBT power loss and dynamically constraining it in the cost function,the performance of optimal voltage vector balancing control can be balanced with power loss.Simulation results show that the proposed method reduces the junction temperature of the power semiconductor and prolongs the converter lifetime compared with the traditional strategy.
基金supported in part by Heilongjiang Provincial Natural Science Foundation of China under Project TD2021E004in part by Ningbo Science and Technology Bureau under S&T Innovation 2025 Major Special Programme with project code 2019B10071。
文摘With the rapid development of the world economy,IGBT has been widely used in motor drive and electric energy conversion.In order to timely detect the fatigue damage of IGBT,it is necessary to monitor the junction temperature of IGBT.In order to realize the fast calculation of IGBT junction temperature,a finite element method of IGBT temperature field reduction is proposed in this paper.Firstly,the finite element calculation process of IGBT temperature field is introduced and the linear equations of finite element calculation of temperature field are derived.Temperature field data of different working conditions are obtained by finite element simulation to form the sample space.Then the covariance matrix of the sample space is constructed,whose proper orthogonal decomposition and modal extraction are carried out.Reasonable basis vector space is selected to complete the low dimensional expression of temperature vector inside and outside the sample space.Finally,the reduced-order model of temperature field finite element is obtained and solved.The results of the reduced order model are compared with those of the finite element method,and the performance of the reduced-order model is evaluated from two aspects of accuracy and rapidity.
文摘There are challenges to the reliability evaluation for insulated gate bipolar transistors(IGBT)on electric vehicles,such as junction temperature measurement,computational and storage resources.In this paper,a junction temperature estimation approach based on neural network without additional cost is proposed and the lifetime calculation for IGBT using electric vehicle big data is performed.The direct current(DC)voltage,operation current,switching frequency,negative thermal coefficient thermistor(NTC)temperature and IGBT lifetime are inputs.And the junction temperature(T_(j))is output.With the rain flow counting method,the classified irregular temperatures are brought into the life model for the failure cycles.The fatigue accumulation method is then used to calculate the IGBT lifetime.To solve the limited computational and storage resources of electric vehicle controllers,the operation of IGBT lifetime calculation is running on a big data platform.The lifetime is then transmitted wirelessly to electric vehicles as input for neural network.Thus the junction temperature of IGBT under long-term operating conditions can be accurately estimated.A test platform of the motor controller combined with the vehicle big data server is built for the IGBT accelerated aging test.Subsequently,the IGBT lifetime predictions are derived from the junction temperature estimation by the neural network method and the thermal network method.The experiment shows that the lifetime prediction based on a neural network with big data demonstrates a higher accuracy than that of the thermal network,which improves the reliability evaluation of system.
基金supported in part by the Shenzhen Col-laborative Innovation Special Plan International Coopera-tion Research Project(No.GJHZ20220913144400001)the General Research Project of Shenzhen Science and Technology Plan(No.JCYJ20220818100000001).
文摘Excessive temperature rise during the operation of the generator system can affect the safety and life cycle of the machine.Therefore,in order to accurately obtain the internal temperature of the switched reluctance generator(SRG),an internal temperature estimation model based on electric heating is established in this paper.First,an im-proved variable coefficient Bertotti loss separation calcula-tion formula is adopted to solve the iron loss of the genera-tor under various operating conditions.Subsequently,the accurate heat source parameters in the temperature model can be obtained,and the corresponding heat source data can be calculated.Then,based on the obtained heat source data,an equivalent thermal circuit model is established for SRG.Meanwhile,in order to effectively reduce the internal temperature during SRG operation,a new water-cooled structure for direct cooling of SRG stator windings is pro-posed in this paper,which can effectively reduce the tem-perature rise during operation,thus improving the reliabil-ity of the generator.Finally,by comparing the equivalent thermal circuit model,finite element thermal model,and experimental temperature measurements of SRG,it is found that results from the equivalent thermal circuit model of the SRG are closer to the measured temperatures,while the effectiveness of the water-cooled structure is verified.
基金Supported by the National Natural Science Foundation of China (52177199).
文摘By integrating a temperature-adaptive function, an active gate driver (AGD) enhances the switching performance of silicon carbide (SiC) MOSFETs under varying temperature conditions. However, the lack of analytical expressions describing the coupling between AGD parameters and temperature variation limits the broader application of this method, particularly in SiC modules that exhibit complicated device transient behaviors. To address this challenge, a mathematical model of the transient behavior of an SiC module is developed to investigate the relationship among AGD parameters, junction temperature, and switching performance. The analysis reveals that the impact of temperature on switching performance is directly linked to the duration of each gate resistance. Accordingly, a temperature-adaptive AGD for SiC MOSFET modules is proposed. Online junction temperature monitoring is achieved using turn-on delay detection, and the duration of each gate’s driving resistance is dynamically adjusted. The proposed temperature-adaptive AGD is validated experimentally using a commercial 1.2 kV/560 A SiC MOSFET at 600 V/200 A. Experimental results across a temperature range of 20 ℃ to 100 ℃ demonstrate that electrical stress variation remains within 15%, while loss variation does not exceed 10%.
基金Special Fund Project of Science and Technology Innovation of Dongli District(21090302)Research Projectof Applied Basic and Front Technologies of Tianjin(10JCZDJC15400)
文摘In order to study the role of printed circuit board(PCB)in high-power LED heat dissipation,a simple model of high-power LED lamp was designed.According to this lamp model,some thermal performances such as thermal resistances of four types of PCB and the changes of LED junction temperature were tested under three different working currents.The obtained results indicate that LED junction temperature can not be lowered significantly with the decreasing thermal resistance of PCB.However,PCB with low thermal resistance can be matched with smaller volume heat sink,so it is hopeful to reduce the size,weight and cost of LED lamp.
文摘Thermal management of LED junction temperature is one of the fundamental technologies for LED lamp to ensure basic specifications in many aspects. Analysed is the high power LED's distribution on heat sink. Using mathematical statistical methods, a formula is conlcuded to calculate the size of heat sink under LED safe working temperature, which provides a method to researchers and LED lamp manufacturers.
基金supported by the National Key Research and Development Program of China (No. 2019YFA0405402)。
文摘The insulated gate bipolar transistor(IGBT)module is one of the most age-affected components in the switch power supply, and its reliability prediction is conducive to timely troubleshooting and reduction in safety risks and unnecessary costs. The pulsed current pattern of the accelerator power supply is different from other converter applications;therefore, this study proposed a lifetime estimation method for IGBT modules in pulsed power supplies for accelerator magnets. The proposed methodology was based on junction temperature calculations using square-wave loss discretization and thermal modeling.Comparison results showed that the junction temperature error between the simulation and IR measurements was less than 3%. An AC power cycling test under real pulsed power supply applications was performed via offline wearout monitoring of the tested power IGBT module. After combining the IGBT4 PC curve and fitting the test results,a simple corrected lifetime model was developed to quantitatively evaluate the lifetime of the IGBT module,which can be employed for the accelerator pulsed power supply in engineering. This method can be applied to other IGBT modules and pulsed power supplies.
基金financially supported by Collaborative Research in Engineering, Science and Technology (CREST) under Grant No. 304/PFIZIK/650601/C121
文摘Boron-doped aluminum nitride （B-AlN） thin films were synthesized on Al substrates by using chemical vapor deposition method by changing the synthesis parameters and were used as thermal interface material for high power light emitting diode （LED）. The B-AlN thin film-coated Al substrate was used as heat sink and studied the performance of high power LED at various driving currents. The recorded transient cooling curve was evaluated to study the rise in junction temperature （Tj）, total thermal resistance （gth_tot） and the substrate thermal resistance （Rth_sub） of the given LED. From the results, the B-AlN thin film （prepared at process 4） interfaced LED showed low Rth-tot and Tj value for all driving currents and observed high difference in Rth_tot （△Rth_tot =2.2 K/W） at 700 mA when compared with the Rth-tot of LED attached on bare Al substrates （LED/Al）. The Tj of LED was reduced considerably and observed 4.7 ℃ as ATj for the film prepared using process 4 condition when compared with LED/Al boundary condition at 700 mA. The optical performance of LED was also tested for all boundary conditions and showed improved lux values for the given LED at 700 mA where B-AlN thin film was synthesized using optimized flow of Al, B and N sources with minimized B and N content. The other optical parameters such as color correlated temperature and color rendering index were also measured and observed low difference for all boundary conditions. The observed results are suggested to use B-AlN thin film as efficient solid thin film thermal interface materials in high power LED.
基金Sponsored by the Heilongjiang Provincial Project(Grant No.12511121)the Harbin City Innovation Talent Project(Grant No.2011RFXXG019)the National Science and Technology Support Project(Grant No.2012BAH28F02)
文摘In this paper,high-power LED with many integrated chips is used as thermal resistance analysis research object, and we do thermal resistance testing technology research on it. We put forward the thermocouple point contact test method. According to the principle that LED forward voltage changes with temperature,LED heat sink to surface temperature distribution is studied directly in the test,and then we analyze the thermal resistance of high-power LED with many integrated chips when its secondary packaging is introduced. This method makes the measurement of thermal resistance of LED more rapid and convenient. It provides an effective assessment method for the analysis of high power LED device design and engineering application.
