CN109600021B - Method and device for determining blockage degree of radiator of converter - Google Patents

Method and device for determining blockage degree of radiator of converter Download PDF

Info

Publication number
CN109600021B
CN109600021B CN201811128323.3A CN201811128323A CN109600021B CN 109600021 B CN109600021 B CN 109600021B CN 201811128323 A CN201811128323 A CN 201811128323A CN 109600021 B CN109600021 B CN 109600021B
Authority
CN
China
Prior art keywords
thermal resistance
determining
sample data
radiator
temperature
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201811128323.3A
Other languages
Chinese (zh)
Other versions
CN109600021A (en
Inventor
刘志刚
黄文勋
曲尚开
丁大鹏
肖梓林
霍长龙
陈杰
付和平
张钢
李庭
漆良波
牟富强
路亮
邱瑞昌
魏路
吕海臣
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
BEIJING QIANSIYU ELECTRIC CO LTD
Original Assignee
BEIJING QIANSIYU ELECTRIC CO LTD
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by BEIJING QIANSIYU ELECTRIC CO LTD filed Critical BEIJING QIANSIYU ELECTRIC CO LTD
Priority to CN201811128323.3A priority Critical patent/CN109600021B/en
Publication of CN109600021A publication Critical patent/CN109600021A/en
Application granted granted Critical
Publication of CN109600021B publication Critical patent/CN109600021B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K7/00—Constructional details common to different types of electric apparatus
    • H05K7/20—Modifications to facilitate cooling, ventilating, or heating
    • H05K7/2089—Modifications to facilitate cooling, ventilating, or heating for power electronics, e.g. for inverters for controlling motor
    • H05K7/209—Heat transfer by conduction from internal heat source to heat radiating structure

Landscapes

  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Investigating Or Analyzing Materials Using Thermal Means (AREA)

Abstract

The embodiment of the invention provides a method and a device for determining the blockage degree of a radiator of a converter, wherein the method comprises the following steps: acquiring a first temperature of the radiator; determining a first thermal resistance according to the first temperature, a preset temperature and the power loss of the converter device; determining a first group of sample data and a second group of sample data corresponding to the first thermal resistance in a sample database, wherein each group of sample data in the sample database comprises a time length and the thermal resistance of the radiator after the time length is operated, and the first thermal resistance is positioned between the second thermal resistance in the first group of sample data and the third thermal resistance in the second group of sample data; and determining the blockage degree of the radiator according to the first thermal resistance, the first set of sample data and the second set of sample data. The accuracy of determining the clogging degree of the radiator is improved.

Description

Method and device for determining blockage degree of radiator of converter
Technical Field
The embodiment of the invention relates to the field of rail transit vehicles, in particular to a method and a device for determining the blockage degree of a radiator of a converter.
Background
Rail transit vehicles (e.g. subways, high-speed railways, etc.) typically have deflectors, which are usually provided with radiators to dissipate heat generated by the deflectors.
In the working process of the radiator, a large amount of dust is adhered to the radiator, so that the radiator is blocked, the heat dissipation function of the radiator on the converter device is influenced, and the safety and reliability of the operation of the rail transit vehicle are further reduced. Therefore, in the practical application process, the blockage degree of the radiator needs to be detected and the blockage needs to be cleaned in time, so that the safety and reliability of the operation of the rail transit vehicle are improved. In the prior art, generally, when the rail transit vehicle stops running, a worker observes the radiator and determines the blockage degree of the radiator according to work experience.
However, when the clogging degree of the radiator is determined manually, it is difficult to accurately determine the clogging degree of the radiator, resulting in low accuracy in determining the clogging degree of the radiator.
Disclosure of Invention
The embodiment of the invention provides a method and a device for determining the blockage degree of a radiator of a converter device, which improve the accuracy of judging the blockage degree of the radiator.
In a first aspect, an embodiment of the present invention provides a method for determining a degree of blockage of a radiator of a deflector, including:
acquiring a first temperature of the radiator;
determining a first thermal resistance according to the first temperature, a preset temperature and the power loss of the converter device;
determining a first group of sample data and a second group of sample data corresponding to the first thermal resistance in a sample database, wherein each group of sample data in the sample database comprises a time length and the thermal resistance of the radiator after the time length is operated, and the first thermal resistance is positioned between the second thermal resistance in the first group of sample data and the third thermal resistance in the second group of sample data;
and determining the blockage degree of the radiator according to the first thermal resistance, the first set of sample data and the second set of sample data.
In one possible embodiment, the determining a clogging degree of the heat sink according to the first thermal resistance, the first set of sample data, and the second set of sample data includes:
obtaining a first difference value of the second thermal resistance and the third thermal resistance;
acquiring a second difference value between the first time length in the first group of sample data and the second time length in the second group of sample data;
and determining the blockage degree according to the first difference value and the second difference value.
In another possible embodiment, the determining a first thermal resistance according to the first temperature, a preset temperature and a power loss of the variable flow device includes:
acquiring a third difference value between the first temperature and the preset temperature;
and determining the ratio of the third difference to the power loss of the variable flow device as the first thermal resistance.
In another possible embodiment, before determining the first thermal resistance according to the first temperature, the preset temperature and the power loss of the variable flow device, the method further includes:
determining a first power loss of the IGBT according to a first current, a first fitting parameter, a second temperature and a first characteristic parameter of the IGBT in the converter device;
determining a second power loss of a diode in the converter device according to a second current, a second fitting parameter, a second temperature and a second characteristic parameter of the diode;
and determining the sum of the first power loss and the second power loss as the power loss of the variable current device.
In another possible embodiment, the difference between the thermal resistances in every two groups of adjacent sample data in the sample database is the same.
In a second aspect, an embodiment of the present invention provides a device for determining a degree of blockage of a radiator of a deflector, including:
an obtaining module, a first determining module, a second determining module, and a third determining module, wherein,
the acquisition module is used for acquiring a first temperature of the radiator;
the first determining module is used for determining a first thermal resistance according to the first temperature, a preset temperature and the power loss of the converter device;
the second determining module is used for determining a first group of sample data and a second group of sample data corresponding to the first thermal resistance in a sample database, wherein each group of sample data in the sample database comprises a time length and a thermal resistance of the radiator after the radiator operates for the time length, and the first thermal resistance is located between a second thermal resistance in the first group of sample data and a third thermal resistance in the second group of sample data;
the third determining module is configured to determine a blockage degree of the heat sink according to the first thermal resistance, the first set of sample data, and the second set of sample data.
In a possible implementation manner, the third determining module is specifically configured to:
obtaining a first difference value of the second thermal resistance and the third thermal resistance;
acquiring a second difference value between the first time length in the first group of sample data and the second time length in the second group of sample data;
and determining the blockage degree according to the first difference value and the second difference value.
In another possible implementation manner, the first determining module is specifically configured to:
acquiring a third difference value between the first temperature and the preset temperature;
and determining the ratio of the third difference to the power loss of the variable flow device as the first thermal resistance.
In another possible embodiment, the apparatus further comprises a fourth determining module, a fifth determining module, and a sixth determining module, wherein,
the fourth determining module is used for determining the first power loss of the IGBT according to the first current, the first fitting parameter, the second temperature and the first characteristic parameter of the IGBT in the converter device;
the fifth determining module is configured to determine a second power loss of the Diode according to a second current, a second fitting parameter, a second temperature, and a second characteristic parameter of a freewheeling Diode in the converter device;
the sixth determining module is configured to determine a sum of the first power loss and the second power loss as a power loss of the converter device.
In another possible embodiment, the difference between the thermal resistances in every two groups of adjacent sample data in the sample database is the same.
In a third aspect, an embodiment of the present invention provides a device for determining a degree of clogging of a radiator of a deflector, including: a processor coupled with a memory;
the memory is used for storing a computer program;
the processor is configured to execute the computer program stored in the memory to enable the terminal device to perform the method of any of the first aspect.
In a fourth aspect, an embodiment of the present invention provides a readable storage medium, which includes a program or instructions, and when the program or instructions are run on a computer, the method according to any one of the first aspect is performed.
According to the method and the device for determining the blockage degree of the radiator, when the blockage degree of the radiator needs to be determined, the first thermal resistance is determined according to the first temperature of the radiator, the preset temperature and the power loss of the converter, the first group of sample data and the second group of sample data corresponding to the first thermal resistance are determined in the sample database, and the blockage degree of the radiator is determined according to the first thermal resistance, the first group of sample data and the second group of sample data. In the process, the heat resistance of the radiator and the blocking degree of the radiator have a certain corresponding relation, and multiple groups of sample data in the sample database can truly reflect the corresponding relation between the heat resistance and the blocking degree. Therefore, according to the thermal resistance of the radiator and the sample data in the sample database, the blockage degree of the radiator can be accurately determined, and the accuracy of the determined blockage degree of the radiator is further improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
Fig. 1 is a schematic structural diagram of a heat sink according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a method for determining a clogging degree of a heat sink according to an embodiment of the present invention;
FIG. 3 is a circuit diagram of the thermal resistance of a heat sink according to an embodiment of the present invention;
fig. 4 is a schematic diagram of a power loss calculation process of a current transformer according to an embodiment of the present invention;
fig. 5 is a schematic view of a first device for determining the clogging degree of a radiator of a deflector according to an embodiment of the present invention;
fig. 6 is a schematic diagram of a radiator blockage degree determination device of a deflector according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious 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.
The rail transit vehicle has the characteristics of safety, comfort, energy conservation, environmental protection and the like, and is the first choice for people to go out. The converter is a core device of a rail transit vehicle, and the radiator is an important part for heat dissipation of the converter, wherein the structural schematic diagram of the radiator is shown in fig. 1.
Fig. 1 is a schematic structural diagram of a heat sink according to an embodiment of the present invention, and please refer to fig. 1, including a heat dissipation substrate 1, heat dissipation fins 2, an air cooling channel 3, and a fan 4.
The heat generated by the converter is diffused to the radiating fins 2 from the radiating base plate 1, and the fan 4 generates strong convection air, so that the heat on the radiating fins 2 is diffused to the air through the air cooling channel 3.
In practice, a large amount of dust is easily adhered to the heat dissipation fins 2 of the heat sink in the inverter, so that the heat sink is blocked, and the effect of heat diffusion on the inverter is affected. In order to accurately determine the degree of blockage of the radiator, the present application provides a method for determining the degree of blockage of the radiator of the deflector, specifically referring to the embodiment shown in fig. 2.
Fig. 2 is a schematic diagram of a method for determining a clogging degree of a heat sink according to an embodiment of the present invention, please refer to fig. 2, which includes:
s201: a first temperature of the heat sink is obtained.
The execution subject of the embodiment of the present invention may be a radiator clogging degree determination device. Alternatively, the device for determining the clogging degree of the radiator may be implemented by software, or may be implemented by a combination of software and hardware.
When the clogging degree needs to be determined, the technical scheme shown in the embodiment shown in fig. 2 may be executed, or the technical scheme shown in the embodiment shown in fig. 2 may be periodically executed according to a preset execution period.
Optionally, the preset execution period is one hour, two hours, and the like.
The radiator is provided with a temperature sensor, and the first temperature of the radiator can be acquired through the temperature sensor.
Alternatively, a plurality of temperature sensors may be disposed at different positions of the heat sink, and the temperatures of the different positions of the heat sink may be obtained by the plurality of temperature sensors.
Alternatively, when the number of the temperature sensors is plural, an average value of the plural temperatures acquired by the plural temperature sensors may be used as the first temperature of the heat sink.
S202: and determining a first thermal resistance according to the first temperature, the preset temperature and the power loss of the converter device.
Optionally, when the preset temperature is zero, the temperature of the radiator is obtained through a temperature sensor on the radiator.
It should be noted that, a ratio of an absolute value of a third difference between the first temperature and the preset temperature to the power loss of the variable flow device may be determined as the first thermal resistance.
For example: assuming that the first temperature is A, the preset temperature is B, the third difference value is C, the power loss of the converter device is D, and the first thermal resistance is R. Then there is a correspondence between A, B, C, D and R as follows:
Figure GDA0002369724210000061
optionally, the thermal resistance varies under the influence of a plurality of factors, the factors include a temperature measurement point of the heat sink, a material of the heat sink, a cooling manner of the heat sink, a flow direction and a flow rate of the coolant, a number, a size and a layout of the power devices, and a circuit diagram of the thermal resistance is shown in fig. 3, which is specifically shown in fig. 3.
FIG. 3 is a circuit diagram of a thermal resistance of a heat sink according to an embodiment of the present invention, referring to FIG. 3, wherein the thermal resistance R of the heat sink is showntotThe method comprises the following steps: thermal conduction resistance R of heat dissipation substrateth,dThermal conduction resistance R of radiating finth,finAnd heat transfer convection resistance R between the heat dissipation substrate and the convection air layerth,aAnd heat transfer convection resistance R between the heat radiating fins and the convection air layerth,a。
In practical application, workers find that a large amount of dust can adhere to the radiating fins 2 to block the radiator, so that the thermal resistance R of the thermal resistance radiator of the radiator is causedtotAnd (4) increasing.
S203: and determining a first set of sample data and a second set of sample data corresponding to the first thermal resistance in a sample database.
Each group of sample data in the sample database comprises a time length and the thermal resistance of the radiator after the time length is operated, and the first thermal resistance is positioned between the second thermal resistance in the first group of sample data and the third thermal resistance in the second group of sample data.
In the sample database, the difference between the thermal resistances in two adjacent sets of sample data is the same.
Alternatively, the sample database may be pre-established and stored in a preset storage area of the radiator clogging degree determining apparatus.
Next, the process of creating the sample database will be described in one step.
When the clogging degree of the radiator is zero, i.e. when the radiator is operated for a time period t during which the clogging degree is zero0When the temperature is 0, the temperature of the radiator at the moment is collected through the temperature sensor, the power loss of the converter device is calculated according to the temperature of the radiator, and the thermal resistance R of the radiator is obtained according to the power loss of the AC device0。
At radiator operation t1During the time, the temperature of the radiator at the moment is collected through the temperature sensor, and the temperature is measured according to the heat dissipationCalculating power loss of the AC device according to the temperature of the radiator, and obtaining thermal resistance R of the radiator according to the power loss of the AC device1。
By analogy, the operation time lengths of a plurality of rail transit vehicles and the thermal resistances of radiators are obtained, the operation time lengths and the thermal resistances form a sample database, and the sample database is shown in table 1.
TABLE 1
Sample data Thermal resistance (K/W) Duration (h) Duration (h) Duration (h)
First set of sample data R0 t0 t′0 t″0
Second set of sample data R1 t1 t′1 t″1
… … … … …
Note that h in table 1 represents a time unit: in hours, K/W is the thermal resistance unit of the heat sink: kelvin/watt.
Next, determining a first set of sample data and a second set of sample data corresponding to the first thermal resistance is exemplified.
Illustratively, assume the sample database is shown in Table 2.
TABLE 2
Sample data Thermal resistance (K/W) Duration (h) Duration (h) Duration (h)
First set of sample data 0.6 0.15 0.2 0.45
Second set of sample data 0.8 0.4 0.7 1.1
… … … … …
Assuming that the first thermal resistance value is 0.71, since 0.71 is between the thermal resistance of sample data 1 (0.6) and the thermal resistance of sample data 2 (0.8), it can be determined that the first set of sample data and the second set of sample data corresponding to the first thermal resistance are sample data 1 and sample data 2, respectively.
S204: and determining the blockage degree of the radiator according to the first thermal resistance, the first group of sample data and the second group of sample data.
And establishing a second database of the thermal resistance range and the blocking degree according to the thermal resistance range in each two adjacent groups of data in the sample database.
The ratio of a first difference between a second thermal resistance of the first set of sample data and a third thermal resistance of the second set of sample data to a second difference between a first time duration in the first set of sample data and a second time duration in the second set of sample data is a slope. Different slopes correspond to different degrees of clogging.
For example, the relationship between different slopes and different degrees of clogging is shown in table 3.
TABLE 3
Figure GDA0002369724210000081
In Table 3, k is1，k1' et al indicate the slope in K/W.h, 5%, …, 100% indicate the degree of occlusion.
Illustratively, assume that the second database is as shown in Table 4.
TABLE 4
Range of thermal resistance 50％ 55％
0.6-0.8 0.6 0.8
… …
For example, according to tables 2 and 4, the first thermal resistance value is 0.71, between the second thermal resistance 0.6 of the first set of sample data and the third thermal resistance 0.8 of the second set of sample data, and the first difference value is 0.8-0.6 ═ 0.2; the first time duration in the first set of sample data is 0.15, and the second time duration in the second set of sample data is 0.4, and the second difference is 0.4-0.15-0.25. The ratio of the first difference 0.2 to the second difference 0.25 is 0.2/0.25 to 0.8, i.e. the slope is 0.8, which corresponds to a blockage level of 55%.
According to the method for determining the blockage degree of the radiator, when the blockage degree of the radiator needs to be determined, a first thermal resistance is determined according to a first temperature of the radiator, a preset temperature and power loss of a converter, a first group of sample data and a second group of sample data corresponding to the first thermal resistance are determined in a sample database, and the blockage degree of the radiator is determined according to the first thermal resistance, the first group of sample data and the second group of sample data. In the process, the heat resistance of the radiator and the blocking degree of the radiator have a certain corresponding relation, and multiple groups of sample data in the sample database can truly reflect the corresponding relation between the heat resistance and the blocking degree. Therefore, according to the thermal resistance of the radiator and the sample data in the sample database, the blockage degree of the radiator can be accurately determined, and the accuracy of the determined blockage degree of the radiator is further improved.
In the process of determining the blockage degree of the radiator, the blockage degree of the radiator is determined without manual observation, so that the labor cost is saved, and the efficiency of determining the blockage degree of the radiator is improved. Further, the blockage degree determining method for the radiator disclosed by the application does not depend on manual observation, so that the blockage degree determining method for the radiator disclosed by the application can be applied to radiators with any structures, and the blockage degree determining method for the radiator disclosed by the application has universality.
In addition, the temperature and the current of the radiator are acquired in real time through the temperature sensor and the current sensor, the blocking degree of the radiator can be acquired in real time after the temperature and the current are accurately calculated, and the problem that in the prior art, the blocking degree can be detected only when the radiator stops running, so that the real-time performance is poor is solved.
On the basis of any of the above embodiments, the power loss calculation process of the inverter device is further described below, and specifically refer to fig. 4.
Fig. 4 is a schematic diagram of a power loss calculation process of a current transformer apparatus according to an embodiment of the present invention, referring to fig. 4, including:
s401: calculated temperature as TkOn-state loss of time-dependent IGBT
Figure GDA0002369724210000091
Average switching loss
Figure GDA0002369724210000092
Calculated temperature as TkOn-state loss of time-Diode
Figure GDA0002369724210000093
Average turn-off loss
Figure GDA0002369724210000094
Note that T iskRepresents the second temperature, IcRepresents the first current (i.e. the on-state current of the IGBT), IfRepresenting the second current (i.e., the off current of the Diode).
Calculated temperature as TkOn-state loss of time-dependent IGBT
Figure GDA0002369724210000095
According to two characteristic curves V of the IGBT at 25 ℃ and 125 ℃ provided by the product manual of the IGBTce-IcBy linear interpolation, the temperature T is obtainedkOf time-domain IGBT
Figure GDA0002369724210000096
Characteristic curve. Will be provided with
Figure GDA0002369724210000097
A plurality of different points on the characteristic curve
Figure GDA0002369724210000098
Multiplying the horizontal and vertical coordinate points to obtain the characteristic curve of the IGBT
Figure GDA0002369724210000099
Namely:
Figure GDA00023697242100000910
in the formula (I), the compound is shown in the specification,
Figure GDA00023697242100000911
at a temperature of TkThe on-state voltage drop of the IGBT is measured, and g represents multiplication.
Performing function fitting on the formula (1) by using a function fitting method to obtain
Figure GDA00023697242100000912
With respect to IcPolynomial of degree 3:
Figure GDA00023697242100000913
in the formula, ak1、ak2、ak3、ak4The first fitting parameters are indicated.
Calculated temperature as TkAverage switching loss of time-dependent IGBT
Figure GDA0002369724210000101
According to the characteristic parameters provided by the product manual of the IGBT under the conditions of 25 ℃ and 125 ℃ (including the first characteristic parameter E)on-Ic、Eoff-Ic) Obtaining the temperature T by linear interpolationkOf the hour
Figure GDA0002369724210000102
Are respectively paired
Figure GDA0002369724210000103
Performing a function fitting for 3 times to obtain:
Figure GDA0002369724210000104
Figure GDA0002369724210000105
in the formula (I), the compound is shown in the specification,
Figure GDA0002369724210000106
at a first current of IcTemperature of TkTurn-on and turn-off energy loss of time IGBT mk1、mk2、mk3、mk4、nk1、nk2、nk3、nk4Are fitting parameters.
Substituting the formula (3) and the formula (4) into the formula (5) to calculate the average switching loss of the IGBT
Figure GDA0002369724210000107
The calculation formula is as follows:
Figure GDA0002369724210000108
in the formula (f)swFor the switching frequency, π is the natural circumference ratio.
Calculated temperature as TkOn-state loss of time-Diode
Figure GDA0002369724210000109
Two characteristic curves V of the Diade at 25 ℃ and 125 ℃ according to the product manual of the Diadef-IfBy linear interpolation, the temperature T is obtainedkOf a time Diode
Figure GDA00023697242100001010
Characteristic curve. Will be provided with
Figure GDA00023697242100001011
A plurality of different points on the characteristic curve
Figure GDA00023697242100001012
Multiplying the horizontal and vertical coordinate points to obtain the characteristic curve of the Diode
Figure GDA00023697242100001013
Namely:
Figure GDA00023697242100001014
in the formula (I), the compound is shown in the specification,
Figure GDA00023697242100001015
at a temperature of TkThe on-state voltage drop of the Diode.
Performing function fitting on the formula (6) by using a function fitting method to obtain
Figure GDA00023697242100001016
With respect to IfPolynomial of degree 3:
Figure GDA00023697242100001017
in the formula, bk1、bk2、bk3、bk4The second fitting parameters are indicated.
Calculated temperature as TkAverage turn-off loss of time diode
Figure GDA00023697242100001018
Characteristic parameters provided at 25 ℃ and 125 ℃ according to the product manual of the Diode (i.e.characteristic curve E)rr-If) Obtaining the temperature T by linear interpolationkTime of flight
Figure GDA00023697242100001019
Then, by using a 3-order function fitting method, the following characteristic curves are obtained:
Figure GDA00023697242100001020
in the formula ok1、ok2、ok3、ok4In order to fit the parameters to the image,
Figure GDA00023697242100001021
at a temperature of TkSubstituting formula (8) into formula (9) to obtain the average turn-off loss of the Diode
Figure GDA0002369724210000111
The calculation formula is as follows:
Figure GDA0002369724210000112
s402: to a temperature TkFirst power loss of time-dependent IGBT
Figure GDA0002369724210000113
And second power loss of the Diode
Figure GDA0002369724210000114
Alternatively, the temperature T may be determined by the following feasible implementationkFirst power loss of time-dependent IGBT
Figure GDA00023697242100001123
Obtained by the formula (2)
Figure GDA0002369724210000115
And obtained by the formula (5)
Figure GDA0002369724210000116
Substituting the formula (10) to obtain the first power loss of the IGBT
Figure GDA0002369724210000117
The calculation formula is as follows:
Figure GDA0002369724210000118
first power loss of IGBT
Figure GDA0002369724210000119
The method comprises static loss, switching loss and driving loss, wherein the static loss is divided into on-state loss and off-state loss, and the switching loss is divided into on-state loss and off-state loss. The off-state loss of the IGBT accounts for a small percentage of the first power loss and is ignored.
Optionally, using average switching losses
Figure GDA00023697242100001110
Calculating the first power loss of the IGBT instead of the sum of the turn-on loss and the turn-off loss of the IGBT
Figure GDA00023697242100001111
Alternatively, the second power loss of the Diode may be determined by a feasible implementation as follows
Figure GDA00023697242100001112
Obtained by the formula (7)
Figure GDA00023697242100001113
And formula (9) to
Figure GDA00023697242100001114
Substituting into equation (11) to obtain the second power loss of the Diode
Figure GDA00023697242100001115
The calculation formula is as follows:
Figure GDA00023697242100001116
note that the second power loss of the Diode
Figure GDA00023697242100001117
The method comprises static loss, switching loss and driving loss, wherein the static loss is divided into on-state loss and off-state loss, and the switching loss is divided into on-state loss and off-state loss. The ratio of the on-state loss and the off-state loss of the Diode in the second power loss is small and ignored.
Optionally, average turn-off loss is used
Figure GDA00023697242100001118
Instead of the turn-off loss of the Diode, the second power loss of the Diode is calculated.
S403: calculated temperature as TkPower consumption meter of time converter
Figure GDA00023697242100001119
Obtained by the formula (10)
Figure GDA00023697242100001120
And obtained by formula (11)
Figure GDA00023697242100001121
Substituting the formula (12) to obtain the power loss of the converter
Figure GDA00023697242100001122
The calculation formula is as follows:
Figure GDA0002369724210000121
the technical solutions shown in the above method embodiments are described in detail below by specific examples.
Illustratively, assume the sample database is as shown in Table 2 above.
Assuming that after the rail transit vehicle runs for a period of time, the first temperature of the radiator at the moment is 333K (K represents a temperature unit Kelvin) acquired by a temperature sensor, and the preset temperature is 303K; the current sensor obtains a first current and a second current when the temperature is 333K, and the power loss P of the alternating current device is calculated according to the first temperature 333K, the first current and the second current by using the formulas (1) - (12)tot(333K)Is 50 watts; the first thermal resistance is then:
Figure GDA0002369724210000122
when the first thermal resistance is 0.6, starting timing until the thermal resistance value reaches the third thermal resistance of the second group of sample data of 0.8, assuming that the elapsed time of the railway vehicle is 0.3 hour, ending timing, calculating the slope of the current time to be (0.8-0.6)/0.3 to be 0.67, and according to the table 4, the slope of 0.67 is 0.6-0.8, so that the blockage degree of the radiator in the current transformer at the current time is 50-55%.
Fig. 5 is a first schematic diagram of a device for determining a blockage degree of a radiator of a deflector according to an embodiment of the present invention. Referring to fig. 5, the apparatus may include an obtaining module 11, a first determining module 12, a second determining module 13, and a third determining module 14, wherein,
the obtaining module 11 is configured to obtain a first temperature of the heat sink;
the first determining module 12 is configured to determine a first thermal resistance according to the first temperature, a preset temperature, and a power loss of the converter device;
the second determining module 13 is configured to determine, in a sample database, a first set of sample data and a second set of sample data corresponding to the first thermal resistance, where each set of sample data in the sample database includes a duration and a thermal resistance of the heat sink after the duration is operated, and the first thermal resistance is located between a second thermal resistance in the first set of sample data and a third thermal resistance in the second set of sample data;
the third determining module 14 is configured to determine a clogging degree of the heat sink according to the first thermal resistance, the first set of sample data, and the second set of sample data.
The device for determining the blockage degree of the radiator of the converter device provided by the embodiment of the invention can execute the technical scheme shown in the embodiment of the method, and the implementation principle and the beneficial effect are similar, so that the detailed description is omitted.
In a possible implementation, the third determining module 14 is specifically configured to:
obtaining a first difference value of the second thermal resistance and the third thermal resistance;
acquiring a second difference value between the first time length in the first group of sample data and the second time length in the second group of sample data;
and determining the blockage degree according to the first difference value and the second difference value.
In another possible implementation manner, the first determining module is specifically configured to:
acquiring a third difference value between the first temperature and the preset temperature;
and determining the ratio of the third difference to the power loss of the variable flow device as the first thermal resistance.
Fig. 6 is a schematic diagram of a radiator blockage degree determination device of a deflector according to an embodiment of the present invention. On the basis of the embodiment shown in fig. 5, please refer to fig. 6, the apparatus further includes a fourth determining module 15, a fifth determining module 16, and a sixth determining module 17, wherein,
the fourth determining module 15 is configured to determine a first power loss of the IGBT according to a first current, a first fitting parameter, a second temperature, and a first characteristic parameter of an insulated gate bipolar transistor IGBT in the converter;
the fifth determining module 16 is configured to determine a second power loss of the Diode according to a second current of a freewheeling Diode in the converter, a second fitting parameter, a second temperature, and a second characteristic parameter;
the sixth determining module 17 is configured to determine a sum of the first power loss and the second power loss as a power loss of the current transformer.
In one possible embodiment, the difference between the thermal resistances in every two sets of adjacent sample data in the sample database is the same.
The device for determining the blockage degree of the radiator of the converter device provided by the embodiment of the invention can execute the technical scheme shown in the embodiment of the method, and the implementation principle and the beneficial effect are similar, so that the detailed description is omitted.
Finally, it should be noted that: the above embodiments are only used for illustrating the technical solutions of the embodiments of the present invention, and are not limited thereto; although embodiments of the present invention have been described in detail with reference to the foregoing embodiments, those skilled in the art will understand 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 such modifications or substitutions do not depart from the spirit and scope of the embodiments of the present invention.

Claims (8)

1. A method for determining the blockage degree of a radiator of a deflector, which is characterized by comprising the following steps:
acquiring a first temperature of the radiator;
determining a first thermal resistance according to the first temperature, a preset temperature and the power loss of the converter device;
determining a first group of sample data and a second group of sample data corresponding to the first thermal resistance in a sample database, wherein each group of sample data in the sample database comprises a time length and the thermal resistance of the radiator after the time length is operated, and the first thermal resistance is positioned between the second thermal resistance in the first group of sample data and the third thermal resistance in the second group of sample data;
determining a blockage degree of the radiator according to the first thermal resistance, the first set of sample data and the second set of sample data;
said determining a blockage level of said heat sink based on said first thermal resistance, said first set of sample data, and said second set of sample data, comprising:
obtaining a first difference value of the second thermal resistance and the third thermal resistance;
acquiring a second difference value between the first time length in the first group of sample data and the second time length in the second group of sample data;
and determining the blockage degree according to the first difference value and the second difference value.
2. The method of claim 1, wherein said determining a first thermal resistance based on said first temperature, a predetermined temperature, and a power loss of said variable flow device comprises:
acquiring a third difference value between the first temperature and the preset temperature;
and determining the ratio of the third difference to the power loss of the variable flow device as the first thermal resistance.
3. The method as claimed in claim 1, wherein before determining the first thermal resistance based on the first temperature, the preset temperature and the power loss of the variable current device, further comprising:
determining a first power loss of the IGBT according to a first current, a first fitting parameter, a second temperature and a first characteristic parameter of the IGBT in the converter device;
determining a second power loss of a Diode according to a second current, a second fitting parameter, a second temperature and a second characteristic parameter of a Diode of the freewheeling Diode in the converter device;
and determining the sum of the first power loss and the second power loss as the power loss of the variable current device.
4. The method of claim 1, wherein the difference between the thermal resistances in each two sets of adjacent sample data in the sample database is the same.
5. The device for determining the blockage degree of the radiator of the converter device is characterized by comprising an acquisition module, a first determination module, a second determination module and a third determination module, wherein,
the acquisition module is used for acquiring a first temperature of the radiator;
the first determining module is used for determining a first thermal resistance according to the first temperature, a preset temperature and the power loss of the converter device;
the second determining module is used for determining a first group of sample data and a second group of sample data corresponding to the first thermal resistance in a sample database, wherein each group of sample data in the sample database comprises a time length and a thermal resistance of the radiator after the radiator operates for the time length, and the first thermal resistance is located between a second thermal resistance in the first group of sample data and a third thermal resistance in the second group of sample data;
the third determining module is used for determining the blockage degree of the radiator according to the first thermal resistance, the first group of sample data and the second group of sample data;
the third determining module is specifically configured to:
obtaining a first difference value of the second thermal resistance and the third thermal resistance;
acquiring a second difference value between the first time length in the first group of sample data and the second time length in the second group of sample data;
and determining the blockage degree according to the first difference value and the second difference value.
6. The apparatus of claim 5, wherein the first determining module is specifically configured to:
acquiring a third difference value between the first temperature and the preset temperature;
and determining the ratio of the third difference to the power loss of the variable flow device as the first thermal resistance.
7. The apparatus of claim 5, further comprising a fourth determination module, a fifth determination module, a sixth determination module, wherein,
the fourth determining module is used for determining the first power loss of the IGBT according to the first current, the first fitting parameter, the second temperature and the first characteristic parameter of the IGBT in the converter device;
the fifth determining module is configured to determine a second power loss of the Diode according to a second current, a second fitting parameter, a second temperature, and a second characteristic parameter of a freewheeling Diode in the converter device;
the sixth determining module is configured to determine a sum of the first power loss and the second power loss as a power loss of the converter device.
8. The apparatus of claim 5, in which the difference between the thermal resistances in every two sets of adjacent sample data in the sample database is the same.
CN201811128323.3A 2018-09-27 2018-09-27 Method and device for determining blockage degree of radiator of converter Active CN109600021B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201811128323.3A CN109600021B (en) 2018-09-27 2018-09-27 Method and device for determining blockage degree of radiator of converter

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201811128323.3A CN109600021B (en) 2018-09-27 2018-09-27 Method and device for determining blockage degree of radiator of converter

Publications (2)

Publication Number Publication Date
CN109600021A CN109600021A (en) 2019-04-09
CN109600021B true CN109600021B (en) 2020-04-07

Family

ID=65957220

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201811128323.3A Active CN109600021B (en) 2018-09-27 2018-09-27 Method and device for determining blockage degree of radiator of converter

Country Status (1)

Country Link
CN (1) CN109600021B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110567739B (en) * 2019-07-16 2020-10-20 北京交通大学 Method and device for rapidly detecting heat dissipation state of radiator

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102192845B (en) * 2010-03-18 2014-04-16 施耐德东芝换流器欧洲公司 Diagnosis method for heat radiation system
CN107590295B (en) * 2016-07-08 2021-02-02 台达电子企业管理（上海）有限公司 Method and device for evaluating condition of heat dissipation system of power module

Also Published As

Publication number Publication date
CN109600021A (en) 2019-04-09

Similar Documents

Publication Publication Date Title
Hefner A dynamic electro-thermal model for the IGBT
CN102192845B (en) Diagnosis method for heat radiation system
CN109600021B (en) Method and device for determining blockage degree of radiator of converter
Yang et al. Transient electro-thermal analysis for a MOSFET based traction inverter
CN110567739B (en) Method and device for rapidly detecting heat dissipation state of radiator
Ni et al. Review of SiC MOSFET based three-phase inverter lifetime prediction
CN110276137A (en) A kind of optimization method of power device radiator
Raciti et al. A new thermal model for power MOSFET devices accounting for the behavior in unclamped inductive switching
US10356854B2 (en) Power conversion apparatus and power conversion method
Chvála et al. Analysis of multifinger power HEMTs supported by effective 3-D device electrothermal simulation
KR102520851B1 (en) Apparatus for estimating junction temperature of IGBT module
CN111060797A (en) IGBT module health state monitoring method based on natural frequency of heat network
CN103870612A (en) System and method for obtaining thermal resistance of IGBT device
CN108072819A (en) The abatement detecting method and device of IGBT
CN110891397A (en) Water cooling system of converter and control method thereof
Li et al. Study on structure optimization of a dual IGBT module heat sink in a DC–DC converter under natural convection based on field synergy theory
CN111339623B (en) Power module temperature estimation method
CN109669112B (en) Junction temperature monitoring method and device for current transformer and IGBT (insulated Gate Bipolar transistor) module of fan
WO2020061889A1 (en) Method and device for determining degree of blockage of radiator of converter device
WO2017130573A1 (en) Power conversion device and thermal resistance measurement method for power module
Peng et al. Analytical model for predicting the junction temperature of chips considering the internal electrothermal coupling inside SiC metal–oxide–semiconductor field‐effect transistor modules
Chakraborty et al. High-fidelity liquid-cooling thermal modeling of a WBG-based bidirectional DC-DC converter for electric drivetrains
Górecki et al. Non-linear compact thermal model of IGBTs
Cheng et al. Dynamic modeling framework for evaluating electromagnetic-electro-thermal behavior of power conversion system during load operation
CN205945494U (en) Intelligence power module and contain its converter

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant