CN114398756A - Semiconductor power device power loss and junction temperature calculation method based on modulation analysis - Google Patents

Semiconductor power device power loss and junction temperature calculation method based on modulation analysis Download PDF

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CN114398756A
CN114398756A CN202111503871.1A CN202111503871A CN114398756A CN 114398756 A CN114398756 A CN 114398756A CN 202111503871 A CN202111503871 A CN 202111503871A CN 114398756 A CN114398756 A CN 114398756A
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水富丽
王武俊
刘志敏
张瑞峰
郭佳
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CRRC Yongji Electric Co Ltd
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Abstract

The invention belongs to the technical field of power loss calculation and electric heating characteristic analysis of IGBT (insulated gate bipolar translator) converter modules, in particular to a semiconductor power device power loss and junction temperature calculation method based on modulation analysis, which solves the technical problems in the background art. The invention avoids the problem of difficult duty ratio calculation under different modulation modes, the calculated loss has better precision, and the fluctuation of the loss in a sine wave period can be reflected; the pulse fluctuation loss is used as input, the forster thermal network model is used as a junction temperature calculation model, the fluctuation of the junction temperature in a sine wave period can be reflected, and compared with the junction temperature calculated only by using thermal resistance information, the calculated maximum junction temperature is more accurate.

Description

Semiconductor power device power loss and junction temperature calculation method based on modulation analysis
Technical Field
The invention belongs to the technical field of power loss calculation and electric heating characteristic analysis of IGBT (insulated gate bipolar transistor) converter modules, relates to modulation analysis, and particularly relates to a semiconductor power device power loss and junction temperature calculation method based on modulation analysis.
Background
As one of the key components of an electric locomotive, a traction converter has been a major focus of various researches. The semiconductor power device is used as the composition foundation and the core of the traction converter, and the performance of the semiconductor power device directly determines the performance index of the traction converter. With the development of power electronic devices such as semiconductor power modules and converters toward light weight, compactness and energy saving, the design of semiconductor power modules is more prominent. The design method for calculating the loss of the power module by using the estimation formula algorithm is relatively extensive at present, and often causes relatively large design margin, so that the design method is not favorable for the design targets of light weight, compactness and energy conservation. The patent aims to solve the problem, and provides a method for designing the junction temperature of the loss design of the semiconductor power device by integrating factors such as a modulation mode, a cooling system and the like from the level of a system level.
The research on the power loss calculation and the electric heating characteristic analysis of the IGBT converter module is roughly divided into three categories:
the first is an on-line junction temperature calculation method for a traction converter as disclosed in patent 201810490961.3, which is based on the signals such as driving pulse, current and the like collected by a traction control unit in real time to calculate the loss and junction temperature in real time, and can capture the dynamic process, and the result is accurate. However, the implementation of the method depends on the control unit, and is not suitable for the condition that the control unit is lacked at the early stage of product design;
and the second method is that power consumption calculation modeling method of the urban rail train traction converter is realized by adopting Matalb/simulink simulation software as 201510344338.3. The simulation calculation tool of the method is limited by the number of load points, so that the practical engineering application of the software tool is limited. The Matalb/simulink simulation model is time-consuming when facing application of various modulation modes, has higher requirement on the capability of designers, and is not beneficial to engineering and modularization;
and thirdly, calculating power loss and junction temperature online, for example, 201410205679.8 discloses an online calculation method for the junction temperature of an IGBT module of a wind power converter, which focuses on the calculation of the junction temperature of the power loss in a switching period, considers the influence of the junction temperature on the loss, and can only accurately calculate the dynamic fluctuation junction temperature of the IGBT module when the output frequency of the wind power converter is low.
Disclosure of Invention
The invention aims to solve the technical problem of how to integrate factors such as a modulation mode, a cooling system and the like in a semiconductor power device loss and junction temperature calculation method, and provides a semiconductor power device power loss and junction temperature calculation method based on modulation analysis.
The technical means for solving the technical problems of the invention is as follows: the method for calculating the power loss and the junction temperature of the semiconductor power device based on modulation and analysis comprises the following four steps:
step one, establishing a mathematical model of a modulation mode according to a specific power electronic topological circuit and the modulation mode thereof, and performing mathematical solution to obtain a device conduction interval in one period under the modulation mode;
step two, constructing a pulse current model of one period according to the power factor, the effective value of the load phase current and the conduction interval obtained in the step one;
calculating the turn-on loss, the turn-off loss and the on-state loss of a device corresponding to each current pulse according to the conducting current pulses so as to obtain the average loss of each current pulse, and finally calculating the average loss of a sine wave period;
and step four, calculating the steady-state junction temperature by taking the average loss of the sine wave period as an initial value of the forster thermal network model, and calculating the junction temperature fluctuation in one sine wave period by taking the pulse loss as dynamic input.
The invention provides a method for establishing modulation pulse and current pulse according to power electronic topology and a modulation mode, which is a whole set of method for calculating the fluctuation of loss in a pulse form according to pulse current data acquired by a modulation mode analysis method, starting from the modulation mode to establish a pulse current model, calculating the pulse loss in a period, inputting the pulse loss into a Foster thermal network model and further calculating the fluctuation junction temperature. Considering from a system level, the method for calculating the loss and the junction temperature of the semiconductor power device is provided, wherein factors such as a modulation mode and a cooling system are integrated, and a refined theoretical calculation support is provided for the design of a light-weight, compact and energy-saving converter.
The invention has the beneficial effects that: the method brings a specific modulation method into the power module pulse current modeling, the established pulse current model is closer to the actual model, the problem of difficult duty ratio calculation under different modulation modes is solved, the calculated loss has better precision, and the fluctuation of the loss in a sine wave period can be reflected; the pulse fluctuation loss is used as input, the forster thermal network model is used as a junction temperature calculation model, the fluctuation of the junction temperature in a sine wave period can be reflected, and compared with the junction temperature calculated only by using thermal resistance information, the calculated maximum junction temperature is more accurate.
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In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
Fig. 1 is a flowchart of a method for calculating power loss and junction temperature of a semiconductor power device based on modulation and analysis according to the present invention.
Fig. 2 is a schematic structural diagram of the two-level voltage source type inverter topology circuit according to the present invention.
Fig. 3 is a diagram of a 15-division two-level SPWM modulation scheme in embodiment 1 of the present invention.
Fig. 4 shows a sine-wave periodic pulse current (positive current is a current flowing through the IGBT, and negative current is a current flowing through the reverse recovery diode) corresponding to fig. 3, when the effective value of the current is 500A and the power factor is 0.9 in embodiment 1 of the present invention.
Fig. 5 is a schematic diagram of pulse loss of the SPWM modulation model in embodiment 1 of the present invention.
Fig. 6 is a model of a thermal network with a water cooling system as described in example 1.
FIG. 7 is a graph of the periodic fluctuations caused by the pulse losses as the system reaches steady state at a water temperature of 50 ℃ as the pulse losses shown in FIG. 5 enter the thermal network model shown in FIG. 6.
Fig. 8 is a schematic diagram of a 7-division-by-60-intermediate system modulated sine wave and triangular carrier.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1:
a method for calculating power loss and junction temperature of a semiconductor power device based on modulation and analysis is shown in fig. 1, wherein a two-level voltage source type inverter topology circuit shown in fig. 2 has structural symmetry, and loss generated by a device on each bridge arm is equal in one period, and is described by taking only an IGBT S1 and an anti-parallel diode D1 on the upper half of the first bridge arm as an example, and the method for calculating the loss and the junction temperature of the circuit by using an SPWM modulation method and adopting the above scheme comprises the following steps:
1) firstly, establishing an SPWM (sinusoidal pulse Width modulation) mathematical model, wherein in order to ensure the universality of the calculation method, the method takes a sine wave period [ 02 pi ] as an example, and the horizontal axis adopts an arc angle;
recording the DC bus voltage as UdcRecording the effective value of the target sine wave line voltage as U, and the modulation ratio corresponding to the SPWM modulation as follows:
Figure BDA0003402664280000031
the SPWM modulated sine wave can then be expressed as:
F1＝M*sin(ω)，
wherein ω is the camber angle;
noting the wave ratio as MF, the SPWM modulated triangular carrier can be represented as F2(01-10) corresponding to
Figure BDA0003402664280000032
Wherein k is 0,1, … …, MF-1;
correspondingly, the modulation of the SPWM within one period can be translated to a modulation in ω e [ 02 π]Upper solution F1≥F2When the mathematical problem is specifically solved, the triangular carrier is described as a plurality of segmentation unary primary expressions, the solution is carried out on a segmentation interval, and finally the solution in the whole period is obtained; as shown in FIG. 3, the triangular carrier wave and the sinusoidal modulated wave in the frequency division modulation system with the modulation ratio of 0.8 and 15 are shown in Table 1, where the modulation system is [ 02 π [ ]]The conduction interval obtained by analysis on the interval is marked as angle, each row corresponds to a conduction interval, the number of the conduction interval is marked as angle _ n, specifically, the first column of data in table 1, the starting arc angle of the angle interval is marked as angle _ on (namely, an on arc angle), specifically, the second column of data in table 1, and the ending arc angle of the angle interval is marked as angle _ off (namely, an off arc angle), specifically, the third column of data in table 1;
TABLE 115 FREQUENCY DIVISION MODULATION ANALYSIS SWITCH ON ANGLE
Figure BDA0003402664280000041
2) Establishing a pulse current model of one period according to the switch conduction angle obtained in the last step:
if the power factor between the voltage and the current is cos (θ) k, and the effective value of the load phase current is a, then in fig. 2, when the motor is operating in the traction condition, the total current flowing through S1 and D1 is:
Figure BDA0003402664280000042
further, the current flowing through S1 is:
Figure BDA0003402664280000043
and the ratio of I > 0 is higher than,
the current through D1 is:
Figure BDA0003402664280000051
and I is less than 0;
given that the effective value of the current is 500A, the power factor is 0.9, and the modulation analysis mode shown in FIG. 3 corresponds to a sine wave periodic pulse current shown in FIG. 4;
3) calculating the turn-on loss, turn-off loss and on-state loss of a device corresponding to each current pulse according to the on-state current pulse, further obtaining the average loss of one current pulse, and finally calculating the average loss of one sine wave period:
a) calculating the turn-on loss, turn-off loss and reverse recovery loss of each current pulse:
for the calculation of the turn-on loss, the turn-off loss and the reverse recovery loss, the calculation can be obtained by fitting according to a curve of a handbook provided by a device manufacturer, and the calculation can be specifically expressed as follows:
any one-time turn-on loss of the IGBT: eoni ═ fon(I) ω — angle — oni, and I > 0,
turn-off loss of any time of the IGBT: eoffi ═ foff(I) ω is angle _ offi, and I > 0,
any one time reverse recovery loss of the diode: ereci ═ frec(| I |), ω ═ angle _ offi, and I < 0,
for the turn-on loss, the device manual is measured under a certain condition of gate resistance, and in practical product application, the gate resistance value is usually modified, and the value has a large influence on the turn-on loss value; when the actually used gate resistance is changed, the values of turn-on loss and turn-off loss are corrected, and the correction still adopts the curve of the turn-on loss changing along with the gate resistance on a device manual, and the curve can be expressed as:
Eonr＝fonr(Ron)，
Eoffr＝foffr(Roff)，
wherein Ron is an on gate resistance and Roff is an off gate resistance;
the effect of the gate resistance on the turn-on loss and the turn-off loss, respectively, can be corrected by the following equation:
Figure BDA0003402664280000052
and the ratio of I > 0 is higher than,
Figure BDA0003402664280000053
and the ratio of I > 0 is higher than,
wherein Ron _ r is an actually adopted on-gate resistance, Ron _ b is a resistance adopted when a relationship between Eon and I is measured on a manual, Roff _ r is an actually adopted off-gate resistance, Roff _ b is a resistance adopted when a relationship between Eoff and I is measured on a manual, Eoni _ r is an on-loss of any pulse corrected by the on-gate resistance, and Eoffi _ r is an off-loss of any pulse corrected by the off-gate resistance;
the effect of the turn-on gate resistance on the diode reverse recovery loss can be expressed as:
Erecr＝frecr(Ron)，
the effect of the gate resistance on the diode reverse recovery loss can be corrected using the following equation:
Figure BDA0003402664280000061
and I is less than 0,
b) calculating the on-state loss of each current pulse:
in the last step, a current model is established, and the on-state loss calculation also needs to obtain the on-state voltage drop of the device, wherein the on-state voltage drop is obtained by fitting a curve provided by a device manufacturer, and the curve is specifically represented as follows:
the conduction saturation voltage drop of the IBGT is: vce ═ fvce(I)，
The conduction saturation voltage drop of the reverse recovery diode is as follows: vf ═ ff(|I|)，
Furthermore, the on-state loss of the IGBT in each on-interval is expressed as an integral using the arc angle as a scale:
Figure BDA0003402664280000062
the on-state loss of the feedback diode in each conducting interval is expressed by taking the arc angle as a scale integral:
Figure BDA0003402664280000063
c) calculating the on-time of each current pulse:
let the modulated sine wave current frequency be F, then the on-time of any modulated current pulse is:
Figure BDA0003402664280000064
d) calculate the average power loss for each current pulse:
the average power loss generated by each current pulse flowing through the IGBT is:
Figure BDA0003402664280000065
wherein the first part is the pulse average on-off loss, and the second part is the pulse average on-state loss; during calculation, the integral algorithm of the on-state loss takes the arc angle as a unit, so that conversion from the arc angle to the time domain is performed when the average loss of the time domain is calculated; fromAs shown in the expression, the on-state loss is independent of the frequency, and the on-off loss is dependent on the frequency (implicit expression, T)iFrequency dependent) the result is consistent with the result of the general estimation expression algorithm;
the average power loss resulting from each current pulse flowing through the reverse recovery diode is:
Figure BDA0003402664280000071
wherein the first part is the pulse average on-off loss, and the second part is the pulse average on-state loss; similarly, conversion from the arc angle to the time domain is carried out when the time domain average loss is calculated;
given a sine wave frequency of 50Hz, the modulation is shown in fig. 3, the current pulses are shown in fig. 4, and the time domain pulse losses are shown in fig. 5;
e) the average loss over one sine wave period is calculated,
the average loss of an IGBT within a sine wave is:
Figure BDA0003402664280000072
the average loss of the reverse recovery diode within a sine wave is:
Figure BDA0003402664280000073
4) calculating junction temperature:
calculating the steady-state junction temperature according to the average power loss of the IGBT in a sine wave period and the average power loss of the reverse recovery diode in the sine wave period; and then taking the pulse loss of the IGBT and the pulse loss of the reverse recovery diode as input, and calculating the dynamic junction temperature in one period by adopting a forster thermal network model.
In junction temperature design, it is not sufficient to calculate the steady state average junction temperature simply as a sine wave cycle average loss. Because the actual loss is generated in a pulse form, the forster heat network model also has inertia (caused by heat capacity), which causes junction temperature fluctuation in a sine wave period during steady-state operation, and the maximum junction temperature which can be reached during steady-state operation is taken as a basis during refined product design rather than the steady-state average value calculated according to the heat resistance.
Here, a water-cooling power module commonly used in a rail transit system is taken as an example to illustrate the necessity of considering dynamic characteristics in the junction temperature calculation. Fig. 6 shows a heat network model with a water cooling system, where Ri1, Ci1, Ri2, Ci2, Ri3, Ci3, Ri4, and Ci4 are thermal resistance and heat capacity parameters of an IGBT four-layer heat network, and Rd1, Cd1, Rd2, Cd2, Rd3, Cd3, Rd4, and Cd4 are thermal resistance and heat capacity parameters of a reverse recovery diode four-layer heat network; ri5, Ci5, Rd5 and Cd5 are thermal resistances of a heat-conducting silicone layer of the IGBT and the reverse recovery diode respectively, and R6 and C6 are thermal resistance and thermal capacity parameters of the water-cooling substrate.
The pulse loss shown in fig. 5 is input into the heat network model shown in fig. 6, the water temperature is 50 ℃, and when the system reaches a steady state, the periodic fluctuation caused by the pulse loss is shown in fig. 7. As can be seen from the figure, relatively large fluctuation can be generated in one period, the fluctuation amplitude of the IGBT is close to 5 ℃, and the fluctuation of the reverse recovery diode is close to 4 ℃; the steady-state junction temperature calculated by only considering the thermal resistance is respectively 2.5 ℃ and 2.3 ℃ lower than the maximum junction temperature calculated by considering the heat capacity factor.
Example 2:
for the SPWM modulation and the division-by-15 modulation in real-time example 1, when the motor is operated in the electric braking condition, the inverter power device loss calculation differs from that of example 1 in that the total current flowing through S1 and D1 is:
Figure BDA0003402664280000081
further, the current flowing through S1 is:
Figure BDA0003402664280000082
and I is less than 0,
the current through D1 is:
Figure BDA0003402664280000083
and I > 0.
Real-time example 3:
in the inverter circuit in embodiment 1, the modulation mode is middle 60 ° modulation, and the steps of calculating the loss and junction temperature by using the scheme described in this patent are as follows:
1) firstly, establishing a mathematical model of middle 60-degree PWM (pulse-width modulation), wherein in order that the calculation method has universality, the method takes a sine wave period [ 02 pi ] as an example, and a horizontal axis adopts an arc angle, and in view of that the middle 60-degree PWM is only modulated in the middle 60-degree of a half wave and has half-wave symmetry, the middle 60-degree PWM is only modulated in the middle 60-degree of the half wave, so that the middle 60-degree PWM is only resolved in [0 pi ] during modulation modeling resolving, and the negative half-wave angle is calculated according to the symmetry;
recording the DC bus voltage as UdcRecording the modulation ratio of the middle 60-degree modulation corresponding to the effective value of the target sine wave line voltage as U as follows:
Figure BDA0003402664280000084
the middle 60 modulated sine wave can then be expressed as:
F1＝M*sin(ω)，
wherein ω is the camber angle;
the score frequency is MF, then the middle 60 PWM is modulated
Figure BDA0003402664280000091
May be denoted as F2＝(0 1 0)，
Figure BDA0003402664280000092
Wherein k is 0,1, … …, (MF-1)/2-1;
correspondingly, the modulation of the SPWM within one period can be translated to a modulation in ω e [0 π]Upper solution F1≥F2The mathematical problem of (2); in the specific solution, the triangular carrier is described as a plurality of segments oneSolving the primary expression in a segmentation interval, and finally obtaining a solution in the whole period; FIG. 8 shows a triangular carrier and a sinusoidal modulation wave under a frequency division modulation scheme of 7; table 2 shows that the modulation method is [ 02 π ]]The conduction interval obtained by analysis on the interval is marked as angle, each row corresponds to a conduction interval, the number of the conduction interval is marked as angle _ n, specifically, the first column of data in table 2, the starting arc angle of the angle interval is angle _ on (namely, the switching-on arc angle), specifically, the second column of data in table 2, and the ending arc angle of the angle interval is angle _ off (namely, the switching-off arc angle), specifically, the third column of data in table 2;
TABLE 27 frequency-division middle 60 ° PWM modulation on-interval table
Figure BDA0003402664280000093
2) 3), 4) the calculations of step are the same as example 1.
Example 4:
for the middle 60 ° 7-degree frequency division modulation in real-time example 3, when the motor operates in the electric braking condition, the inverter power device loss calculation is different from that in example 3 in that, in the second step, the total current flowing through S1 and D1 is as follows:
Figure BDA0003402664280000094
further, the current flowing through S1 is:
Figure BDA0003402664280000101
and I is less than 0,
the current through D1 is:
Figure BDA0003402664280000102
and I > 0.
Example 5:
the inverter circuit in embodiment 1 operates under a traction condition, the modulation mode is SHEPWM modulation, and the steps of calculating the loss and junction temperature by adopting the scheme described in the patent are as follows:
1) firstly, a mathematical model of SHEPWM modulation is established, and for the universality of the calculation method, the method takes a sine wave period [ 02 pi ] as an example, and the horizontal axis adopts an arc angle. The output waveform modulated by SHEPWM must have switching actions at 0 degree, 180 degrees and 360 degrees, and the symmetry of the waveform of the keeper is realized only by knowing the switching angle of the waveform on [0 pi/2 ], and the rest switching angles can be conveniently obtained according to the symmetry, so that the switching angle is solved on [0 pi ] only when the modeling is used for solving the switching angle;
recording the DC bus voltage as UdcRecording the effective value of the target sine wave line voltage as U, and the modulation ratio corresponding to SHEPWM modulation as follows:
Figure BDA0003402664280000103
based on symmetry, the voltage waveform of the bipolar SHEPWM only contains odd harmonic components, and the Fourier series expression form is as follows:
Figure BDA0003402664280000104
Figure BDA0003402664280000105
wherein, UmnThe amplitude of the N-th harmonic wave, the plus sign corresponds to the waveform of the modulation voltage starting at a high level, the sign corresponds to the waveform of the modulation voltage starting at a low level, and N corresponds to the number of the switching angles; solving for the switching angle alphaiThe system of equations of (1) is:
Figure BDA0003402664280000106
in the above equation set, the variables to be solved are N switching angles alphaiN equations are needed to solve, and only N can be eliminated on the basis of meeting the requirement of fundamental wave-1 th harmonic;
given an initial value, for example, a voltage modulation waveform starting at low level with N being 5 and M being 0.8
Figure BDA0003402664280000111
Solving the transcendental equation by means of the MATLAB tool to α ═ 0.17710.40360.50170.81030.8660]，
Further according to the symmetry, the switching angle conduction interval is shown in table 3, the conduction interval is marked as angle, each row corresponds to one conduction interval, the number of the conduction interval is marked as angle _ n, specifically, the first column of data in table 3, the turn-on arc angle is marked as angle _ on (i.e., the starting arc angle of the angle interval), specifically, the second column of data in table 3, and the turn-off arc angle is marked as angle _ off (i.e., the ending arc angle of the angle interval), specifically, the third column of data in table 3;
table 3 when N is 5, SHEPWM modulation on-interval table
Figure BDA0003402664280000112
2) 3), 4) the calculations of step are the same as example 1.
Example 6:
the inverter circuit in embodiment 1 operates in a braking condition, the modulation mode is SHEPWM modulation, and the loss and junction temperature calculation is performed by using the scheme described in this patent, which is different from embodiment 5 in that, in the second step, the current model, the total current flowing through S1 and D1 is:
Figure BDA0003402664280000113
further, the current flowing through S1 is:
Figure BDA0003402664280000121
and I is less than 0,
the current through D1 is:
Figure BDA0003402664280000122
and I > 0.
In practical application, the modulation modes are various, the application of the method is not limited to the SPWM, the middle 60-degree PWM, the SHEPWM and other modulation modes in practical examples, the patent only takes a two-level circuit as an example, and in practical application, a two-level rectification topology circuit, a three-level inversion topology circuit or other multi-level topology circuits are also applicable to the method for the loss junction temperature design calculation.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims (5)

1. The method for calculating the power loss and the junction temperature of the semiconductor power device based on modulation and analysis is characterized by comprising the following four steps:
step one, establishing a mathematical model of a modulation mode according to a specific power electronic topological circuit and the modulation mode thereof, and performing mathematical solution to obtain a device conduction interval in one period under the modulation mode;
step two, constructing a pulse current model of one period according to the power factor, the effective value of the load phase current and the conduction interval obtained in the step one;
calculating the turn-on loss, the turn-off loss and the on-state loss of a device corresponding to each current pulse according to the conducting current pulses so as to obtain the average loss of each current pulse, and finally calculating the average loss of a sine wave period;
and step four, calculating the steady-state junction temperature by taking the average loss of the sine wave period as an initial value of the forster thermal network model, and calculating the junction temperature fluctuation in one sine wave period by taking the pulse loss as dynamic input.
2. The method for calculating the power loss and the junction temperature of the semiconductor power device based on the modulation analysis as claimed in claim 1, wherein in the step one, the modulation analysis takes the arc angle as a scale to obtain the conduction interval of the power device on [ 02 pi ], and the conduction interval is marked as angle.
3. The method for calculating the power loss and the junction temperature of the semiconductor power device based on the modulation analysis according to claim 1, wherein the pulse current model in the second step is as follows: recording the power factor between the voltage and the current as cos (theta) k, and recording the effective value of the load phase current as A, the pulse current model is as follows:
Figure FDA0003402664270000012
4. the method for calculating power loss and junction temperature of a semiconductor power device based on modulation and analysis as claimed in claim 1, wherein the loss calculation formula of each pulse current in the third step is as follows:
opening loss: eon ═ fon(I),ω＝angle_on，
Turn-off loss: eoff is foff(I),ω＝angle_off，
And (3) on-state loss:
Figure FDA0003402664270000011
wherein, angle _ on is a starting arc angle of an angle interval, and angle _ off is an ending arc angle of the angle interval.
5. The method for calculating power loss and junction temperature of a semiconductor power device based on modulation and analysis as claimed in claim 1, wherein in the first step, the power electronic topology circuit is a two-level voltage source type inverter topology circuit, a two-level rectifier topology circuit, a three-level rectifier topology circuit or a three-level inverter topology circuit, and the modulation method is SPWM modulation, middle 60 ° PWM modulation or SHEPWM modulation.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116338299A (en) * 2023-05-29 2023-06-27 广东电网有限责任公司佛山供电局 Method and system for testing output power factor of charging module of direct current system

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116338299A (en) * 2023-05-29 2023-06-27 广东电网有限责任公司佛山供电局 Method and system for testing output power factor of charging module of direct current system
CN116338299B (en) * 2023-05-29 2023-08-04 广东电网有限责任公司佛山供电局 Method and system for testing output power factor of charging module of direct current system

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