CN108375723A - Elevator frequency converter IGBT junction temperatures on-line measuring device and method - Google Patents
Elevator frequency converter IGBT junction temperatures on-line measuring device and method Download PDFInfo
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- CN108375723A CN108375723A CN201810271940.2A CN201810271940A CN108375723A CN 108375723 A CN108375723 A CN 108375723A CN 201810271940 A CN201810271940 A CN 201810271940A CN 108375723 A CN108375723 A CN 108375723A
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- G—PHYSICS
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- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
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Abstract
This application involves a kind of elevator frequency converter IGBT junction temperatures on-line measuring device and methods.Described device includes：Circuit occurs for the micro-current being connect with IGBT circuits, for applying constant current to IGBT circuits before elevator starts operation；The detection circuit being connect with the IGBT circuits, for measuring the saturation voltage drop after the IGBT circuits apply the constant current；The controller being connect with the detection circuit, for determining that elevator starts preceding junction temperature according to the saturation voltage drop.The device and method can directly measure the saturation voltage drop of IGBT by detection circuit, and the junction temperature of determining elevator IGBT is removed further according to saturation pressure, the method for going estimation junction temperature by measuring the shell temperature of IGBT instead of tradition.Realize the junction temperature value that accurate on-line measurement goes out IGBT.
Description
Technical field
This application involves frequency converter temperature detection technical fields, online more particularly to a kind of elevator frequency converter IGBT junction temperatures
Detection device and method.
Background technology
With the development of ac-dc conversion technology, frequency converter is widely applied.Also, skyscraper such as rain in recent years
Occur as spring bamboo afterwards in people's lives so that elevator is also applied more and more extensive.Due in order to ensure the comfort of elevator, electricity
Ladder is mostly used frequency converter regulation and control speed and is run and loaded with non-constant velocities and is not fixed, so the power module IGBT of frequency converter
The power of (Insulated Gate Bipolar Transistor, insulated gate bipolar transistor) can ceaselessly change, and
Power module IGBT can have loss in use, cause the junction temperature of IGBT can be higher and higher, when junction temperature is more than limit value
IGBT will be damaged.
The method of the common detection elevator frequency converter IGBT junction temperatures of tradition is that temperature sensing is placed between IGBT and radiator
Device detects the shell temperature of IGBT, by the junction temperature value of the situation of change of IGBT shell temperature estimation IGBT, that is, traditional detection method without
Method direct-on-line measures the junction temperature value of IGBT, causes to detect IGBT junction temperature value inaccuracy.
Invention content
Based on this, it is necessary in view of the above technical problems, provide a kind of elevator for capableing of accurate on-line measurement IGBT junction temperatures
Frequency converter IGBT detection devices and method.
A kind of elevator frequency converter IGBT junction temperature on-line measuring devices, including：
Circuit occurs for the micro-current being connect with IGBT circuits, for applying constant current to IGBT；
The detection circuit being connect with the IGBT circuits, for measuring after the IGBT circuits apply the constant current
Saturation voltage drop；
The controller being connect with the detection circuit, for determining junction temperature value according to the saturation voltage drop；
The IGBT circuits are isolated and the isolation circuit of circuit occurs for the detection circuit, micro-current.
In one of the embodiments, the micro-current occur circuit include input terminal connect with power supply, output end and institute
State the constant-current source of IGBT circuits connection.
The detection circuit includes the first subtracter and the second subtracter in one of the embodiments,；
Output end, the reverse input end of the noninverting input connection constant-current source of first subtracter connect the IGBT electricity
Road, output end connect the reverse input end of second subtracter；Described in the noninverting input connection of second subtracter
IGBT circuits, output end connect the controller.
The detection circuit further includes the first follower and the second follower in one of the embodiments,；
The in-phase input end of first follower connects the output end of the constant-current source；The reverse phase of first follower
Input terminal connects the output end of first follower；The output end of first follower connects the same of first subtracter
To input terminal；The inverting input of second follower connects the output end of second follower；Second follower
Output end connect the noninverting input and reverse input end of the reverse input end of first subtracter, the second subtracter.
The isolation circuit includes the first diode and the second diode in one of the embodiments,；
The anode of first diode connects the output end of the constant-current source；The cathode of first diode connects institute
State the in-phase input end of the second follower；The anode of second diode connects the in-phase input end of second follower；
The anode of second diode connects the IGBT circuits.
Described device further includes the contactor being connect with IGBT circuits in one of the embodiments,.
The controller is additionally operable to obtain the load value of elevator in one of the embodiments, and elevator starts preceding junction temperature；
The variations injunction temperature value of tested point is determined according to the load value；It is obtained according to the variations injunction temperature value of junction temperature before the startup and tested point
Take the junction temperature value of tested point.
A kind of elevator frequency converter IGBT junction temperature online test methods run on elevator frequency converter IGBT junction temperature on-line checkings dress
Any one of them controller is set, the method step includes：
It controls micro-current and circuit occurs to IGBT circuits application constant current；
Control detection circuit measures the IGBT circuits and applies the saturation voltage drop after the constant current；
Junction temperature value is determined according to the saturation voltage drop.
Described the step of determining junction temperature value according to the saturation voltage drop, includes in one of the embodiments,：
It obtains the load value of elevator and elevator starts preceding junction temperature；
The variations injunction temperature value of tested point is determined according to the load value；
Junction temperature and the variations injunction temperature value of tested point obtain the junction temperature value of tested point before being started according to the elevator.
The step of variations injunction temperature value that tested point is determined according to the load value is wrapped in one of the embodiments,
It includes：
Obtain variations injunction temperature curve when elevator is run under different loads value；
According under the different loads value run when variations injunction temperature curve determine elevator the load value tested point
Variations injunction temperature value.
A kind of computer equipment, including memory and processor, the memory are stored with computer program, and feature exists
In the processor realizes that elevator frequency converter IGBT junction temperatures described in any one of the above embodiments are examined online when executing the computer program
Survey method.
A kind of computer readable storage medium, is stored thereon with computer program, which is characterized in that the computer program
Elevator frequency converter IGBT junction temperature online test methods described in any one of the above embodiments are realized when being executed by processor.
Above-mentioned elevator frequency converter IGBT detection devices and method occur circuit by micro-current and apply constant electricity to IGBT
It flows, the saturation voltage drop after detection circuit measurement IGBT circuits application constant current is sent to controller, and controller is according to saturation pressure
Drop determines the junction temperature of elevator before activation.Above-mentioned apparatus and method can directly measure the saturation pressure of IGBT by detection circuit
Drop, the junction temperature of determining elevator is removed further according to saturation pressure, goes to the side of estimation junction temperature by measuring the shell temperature of IGBT instead of tradition
Method, realize can accurate on-line checking go out the junction temperature value of IGBT.
Description of the drawings
Fig. 1 is the structural schematic diagram of elevator frequency converter IGBT junction temperature on-line measuring devices in one embodiment；
Fig. 2 is the circuit diagram of elevator frequency converter IGBT junction temperature on-line measuring devices in one embodiment；
Fig. 3 is the circuit diagram of elevator frequency converter IGBT junction temperature on-line measuring devices in another embodiment；
Fig. 4 is the flow diagram of elevator frequency converter IGBT junction temperature online test methods in one embodiment；
Fig. 5 is the flow diagram for determining elevator junction temperature value in one embodiment according to saturation voltage drop；
Fig. 6 is the flow diagram for the variations injunction temperature value for determining tested point in one embodiment according to load value；
Fig. 7 is the curve synoptic diagram that variations injunction temperature curve is fitted in one embodiment；
Fig. 8 is the internal structure chart of one embodiment Computer equipment.
Specific implementation mode
It is with reference to the accompanying drawings and embodiments, right in order to make the object, technical solution and advantage of the application be more clearly understood
The application is further elaborated.It should be appreciated that specific embodiment described herein is only used to explain the application, not
For limiting the application.
In one embodiment, as shown in Figure 1, providing a kind of elevator frequency converter IGBT (Insulated Gate
Bipolar Transistor, insulated gate bipolar transistor) junction temperature on-line measuring device 100, which includes and IGBT is electric
The micro-current of road connection occurs circuit 200, the detection circuit 300 that is connect with IGBT circuits and is connect with detection circuit 300
Controller 400.IGBT junction temperatures on-line measuring device 100 further includes isolation circuit 500, and IGBT circuits are connected by isolation circuit 500
It connects detection circuit 300 and circuit 200 occurs for micro-current.Specifically, circuit 200 occurs for micro-current, for applying to IGBT circuits
Constant current.Detection circuit 300 is used to measure IGBT circuits and applies the saturation voltage drop after constant current.Controller 400 is used for root
Junction temperature value is determined according to the saturation voltage drop that detection circuit measures.
Isolation circuit 500 is used to occur micro-current the height of circuit 200 and detection circuit 300 and the IGBT circuits of frequency converter
Pressure and high current are environmentally isolated out.Due to the presence of isolation circuit 500, which can transport always
Row ensures the normal operation of frequency converter without shutdown.
The compound full-control type voltage that IGBT is made of BJT (double pole triode) and MOS (insulating gate type field effect tube)
Drive-type power semiconductor has advantage of both the high input impedance of MOSFET and the low conduction voltage drop of GTR concurrently.Due to
IGBT combines the advantages of both the above device, and driving power is small and saturation pressure reduces.Therefore being highly suitable for DC voltage is
Converter system of 600v or more, such as alternating current generator, frequency converter etc..
Existing elevator mostly uses frequency converter and carries out speed regulating control, but since elevator operation is with non-constant velocities and electricity
Terraced load weight is not fixed, and power converter output is caused constantly to change.IGBT is being connected as the power module of frequency converter
State or open-off state can all have certain consume so that the junction temperature of IGBT can be higher and higher.But IGBT junction temperatures
There is the limitation of maximum temperature, if junction temperature is more than limitation, IGBT will be damaged easily.Therefore in order to ensure frequency converter long-term safety
Reliable operation, needs the junction temperature to frequency converter IGBT to be detected.Tradition places temperature usually between IGBT and radiator
Sensor estimates junction temperature value by the shell temperature of temperature sensor measurement IGBT, can not directly and accurately measure junction temperature.
However, above-mentioned elevator frequency converter IGBT junction temperature measurement devices, for increasing micro-current on the basis of IGBT circuits
Circuit 200 and detection circuit 300 occurs.Circuit 200 occurs by micro-current and applies constant electric current to IGBT circuits, then by examining
The detection of slowdown monitoring circuit 300 applies the saturation voltage drop of the IGBT after constant current, is closed according to the function between saturation voltage drop and junction temperature value
System obtains the junction temperature value of elevator.Above-mentioned apparatus has banned the method that tradition estimates junction temperature by measuring IGBT shell temperature, and realizing can
With the accurate junction temperature for measuring acquisition IGBT online.
In one embodiment, as shown in Fig. 2, being the circuit diagram of elevator frequency converter IGBT junction temperature on-line measuring devices.Its
In, it includes that input terminal connects with power supply VCC that circuit 200, which occurs, for the micro-current in elevator frequency converter IGBT junction temperature on-line measuring devices
It connects, the constant-current source I of output end and IGBT circuits connection.Power supply VCC is the driving power in IGBT circuits, for being supplied for constant-current source
Electricity provides Current Voltage, and constant-current source I is used to ensure that the electric current that power supply VCC is provided to be in steady state.
In one embodiment, the detection circuit 300 in elevator frequency converter IGBT junction temperatures on-line measuring device includes first
Subtracter 310 and the second subtracter 320.
Specifically, the output end of the noninverting input connection constant-current source of the first subtracter 310, reverse input end connect IGBT
Circuit, output end connect the reverse input end of the second subtracter 320.The noninverting input connection IGBT electricity of second subtracter 320
Road, output end connect controller 400.
In another embodiment, detection circuit 300 further includes the first follower U3 and the second follower U4.Wherein, with
It is used for increasing impedance with device, plays buffering isolation in circuit.
Specifically, the output end of the in-phase input end connection constant-current source I of the first follower U3；The reverse phase of first follower U3
Input terminal connects the output end of the first follower U3；The output end of first follower U3 connects the in the same direction defeated of the first subtracter 310
Enter end；The inverting input of second follower U4 connects the output end of the second follower U4；The output end of second follower U4 connects
Connect the reverse input end of the first subtracter 310, the noninverting input and reverse input end of the second subtracter 320.
In one embodiment, as shown in figure 3, being the circuit of another elevator frequency converter IGBT junction temperature on-line measuring devices
Figure.Wherein, 310 and second subtracter 320 of the first subtracter shown in Fig. 2 is built by operational amplifier and resistance,
The quantity of operational amplifier and resistance can be set according to practical situations when building subtracter using operational amplifier and resistance.
In the present embodiment, a preferably operational amplifier and four resistance.
Specifically, the first subtracter 310 includes the first operational amplifier U1, first resistor R1, second resistance R2, third electricity
Hinder R3 and the 4th resistance R4.Second subtracter 320 includes second operational amplifier U2, the 5th resistance R5, the 6th resistance R6, the 7th
Resistance R7 and the 8th resistance R8.The reverse phase of the inverting input connection second operational amplifier U2 of first operational amplifier U1 is defeated
Enter end.
The first end of first resistor R1 connects the output end of the first follower U3, and second end connects the first operational amplifier U1
In-phase input end.The same phase of the second end and the first operational amplifier U1 of the first end connection first resistor R1 of second resistance R2
Input terminal, second end ground connection.3rd resistor R3 first ends connect the output end of the second follower U4, and second end connects the first operation
The inverting input of amplifier U1.The second end and the first operational amplifier U1 of the first end connection 3rd resistor of 4th resistance
Inverting input, second end connect the inverting input of the output end and second operational amplifier U2 of the first operational amplifier U1.
The first end of 5th resistance R5 connects the first end of the output end and 3rd resistor R3 of the second follower U4, second end connection second
The in-phase input end of operational amplifier U2.The first end of 6th resistance R6 connects the second end of the 5th resistance R5 and the second operation is put
The in-phase input end of big device U2, second end ground connection.The first end of 7th resistance R7 connects the second end and first of the 4th resistance R4
The output end of operational amplifier U1, second end connect the inverting input of second operational amplifier U2.The first of 8th resistance R8
The inverting input of the second end and second operational amplifier U2 of the 7th resistance R7 of end connection, second end connect the second operation amplifier
The output end of device U2.
In one embodiment, detection circuit 300 further includes linear optical coupling U5.Wherein, linear optical coupling is a kind of for mould
The optocoupler of quasi- signal isolation, can be isolated electric current, protect and be tested object and test circuit, reduce environmental disturbances to test
The influence of circuit.
Specifically, the output end of the input terminal connection second operational amplifier U2 of linear optical coupling U5, linear optical coupling U5's is defeated
Outlet connects controller 400.In the present embodiment, the saturation voltage drop measured cannot be directly output to controller, in order to reduce
Interfere and play buffer action.The saturation voltage drop measured is passed through linear optical coupling U5 by the second operational amplifier U2 of detection circuit
It exports to controller.
In one embodiment, isolation circuit 500 includes the first diode D1 and the second diode D2.First diode D1
Anode connection constant-current source I output end；The cathode of first diode D1 connects the in-phase input end of the second follower U4；Second
The in-phase input end of the second follower U4 of anode connection of diode D2；The anode connection IGBT circuits of second diode D2.
Specifically, when saturation voltage drop due to measuring IGBT circuits in detection circuit 300, while isolation circuit can also be measured
The pressure drop of diode in 500.Also, because the pressure drop of different temperatures and the diode under different electric currents can be different, in order to
Diode drop is avoided to the influence of detection circuit 300, improves the accuracy of detection circuit, it is identical using two in the present embodiment
The Diode series of model constitute isolation circuit 500.If of less demanding to the accuracy of detection circuit 300 according to actual conditions
It can also be only with a diode.If also, isolation circuit 500 is only with a diode, the subtraction in detection circuit 300
Device can remove, and only use a follower.
In one embodiment, described device further includes the 10T contactors 600 being connect with IGBT circuits.
Specifically, in the present embodiment, the motor that frequency converter is driven belongs to inductive load, therefore in emergent stopping frequency conversion
When device, flowing through the electric current of IGBT will not stop immediately.Therefore increase 10T contactors to may be implemented quickly to break the electricity for flowing through IGBT
Stream.
In one embodiment, before elevator starts operation, I pairs of power supply VCC and constant-current source in circuit 200 occur for micro-current
After IGBT circuits apply constant electric current, the first subtracter 310 in detection circuit 300 passes through the first follower U3 outputs first
The pressure drop V of diode D1D1.The saturation voltage drop V that the output valve of second subtracter 320 is the IGBT detectedCEWith the second diode
The pressure drop V of D2D2Sum subtracts the pressure drop V of the first diode D1 againD1, i.e. the output valve of the second subtracter U2 is VCE+VD2-
VD1。
Since the first diode D1 and the second diode D2 are identical two diodes of model, and residing temperature and institute
The electric current of conducting is essentially identical, therefore, VD2≈VD1.So the output valve of the second subtracter 320 is VCE+VD2-VD1≈VCE, VCE
It is exactly the saturation voltage drop that detection circuit 300 measures.
In one embodiment, controller 400 is additionally operable to obtain the load value of elevator and elevator starts preceding junction temperature.According to negative
Load value determines the variations injunction temperature value of tested point.The junction temperature of tested point is obtained according to junction temperature before startup and the variations injunction temperature value of tested point
Value.
In one embodiment, IGBT circuits include driving circuit and IGBT.Driving circuit connects IGBT.
In one embodiment, driving circuit includes power supply, capacitance and resistance.
Above-mentioned elevator frequency converter IGBT detection devices occur circuit by micro-current and apply constant current, detection to IGBT
Saturation voltage drop after circuit measuring IGBT circuits application constant current is sent to controller, and controller determines electricity according to saturation voltage drop
The junction temperature of ladder.Above-mentioned apparatus can measure the saturation voltage drop of IGBT by detection circuit direct-on-line, be removed further according to saturation pressure
The junction temperature for determining elevator, the method for going estimation junction temperature by measuring the shell temperature of IGBT instead of tradition, realizing can be online accurate
Really measure the junction temperature value of IGBT.
In one embodiment, as shown in figure 4, a kind of elevator frequency converter IGBT junction temperature online test methods, this method fortune
Row is in controller shown in Fig. 3.Include the following steps S402 to S406：
S402, control micro-current occur circuit and apply constant current to IGBT circuits.
Specifically, controller control micro-current occurs circuit and applies constant current to IGBT circuits.Wherein, permanent by applying
Constant current can avoid generating variations injunction temperature due to the fluctuation of operating current, be conducive to the essence for further increasing subsequent detection
Degree.S404, control detection circuit measure IGBT circuits and apply the saturation voltage drop after constant current.Wherein, IGBT saturation voltage drops are just
It is the voltage between transistor collector C and emitter E when IGBT (insulated gate bipolar transistor) reaches saturation conduction
Difference.Specifically, after circuit, which occurs, for controller control micro-current applies constant current to IGBT circuits, control detection circuit measures
IGBT circuits apply the saturation voltage drop after constant current.
S406 determines junction temperature value according to saturation voltage drop.
In one embodiment, as shown in figure 5, determining that junction temperature value includes the following steps S502 extremely according to saturation voltage drop
S506：
S502, obtains the load value of elevator and elevator starts preceding junction temperature.
Specifically, the weight of carrying when load value is elevator actual motion, the same operation curve of synchronization, difference are negative
The output current of the elevator of load is different.Therefore, it in order to accurately measure the junction temperature value of elevator in real time, needs to consider that elevator is negative in difference
The case where load and the load value for obtaining elevator.Junction temperature is junction temperature value when elevator is not run also before starting.Elevator is in actual motion
When junction temperature value can change, therefore the real-time junction temperature value of elevator may know that according to junction temperature before startup and variations injunction temperature value.
S504 determines the variations injunction temperature value of tested point according to the load value.
Specifically, due under elevator different loads electric current it is different, junction temperature value can be according to the weight that elevator is carried
It is different and change, variations injunction temperature value when determining that elevator is under present load according to the load value of elevator.
S506, junction temperature and the variations injunction temperature value of tested point obtain the junction temperature value of tested point before being started according to the elevator.
Specifically, it is determined that elevator needs to measure the point of junction temperature value, the junction temperature before operation is started by the elevator of acquisition, and
The variations injunction temperature value in the case of the tested point, elevator actual loading value is being measured, by junction temperature value before startup and variations injunction temperature
Value carries out being added the real-time junction temperature value that can accurately obtain the tested point.
Elevator frequency converter IGBT detection methods control micro-current by controller and circuit occur to the constant electricity of IGBT applications
After stream, control detection circuit measures IGBT circuits and applies the saturation voltage drop after constant current, and detection circuit simultaneously sends out measurement result
Controller is given, controller determines the junction temperature of elevator according to saturation voltage drop.The above method can pass through detection circuit direct-on-line
The saturation voltage drop for measuring IGBT, the junction temperature of determining elevator is removed further according to saturation pressure, passes through the shell of measurement IGBT instead of tradition
The method that temperature goes estimation junction temperature, realizes the junction temperature value that can accurately measure IGBT online.
In another embodiment, the step of obtaining junction temperature before elevator starts, specifically includes following steps S11 to S12：
S11 obtains the function relation curve of junction temperature and saturation voltage drop.
In the present embodiment, the function relation curve of junction temperature and saturation voltage drop is obtained and stored in memory previously according to experiment
In.Since PN junction is when being connected identical low current, the pressure drop on PN junction can change with variations injunction temperature, so this rule can
For obtaining the function relation curve of junction temperature and saturation voltage drop in the application.Specifically experimentation is：It will be with frequency converter model
Identical IGBT to be measured is put into experiment incubator, and Temperature of Warm Case range is set as -20 DEG C~150 DEG C.Ensure that each temperature becomes
A period of time can be maintained so that the junction temperature of IGBT is identical as environment temperature after change.Then, constant low current is connected to IGBT, surveys
Corresponding saturation voltage drop at this ambient temperature is measured, the function relation curve of junction temperature and saturation voltage drop is obtained.
Specifically, IGBT is placed in incubator, the test temperature of incubator is set as 20 DEG C.The environment of incubator is maintained always
Temperature is 20 DEG C, and until the junction temperature of IGBT is consistent according to the temperature of incubator, that is, IGBT junction temperatures equally reach 20 DEG C
When can to IGBT apply constant current.It measures it and applies the saturation voltage drop after constant current, be in junction temperature temperature by IGBT
The data record of corresponding saturation voltage drop is got off at 20 DEG C.Likewise, repeating aforesaid operations, the test temperature of incubator is arranged
For any moment in -20 DEG C~150 DEG C, corresponding saturation voltage drop under the test temperature is recorded.Finally all data preparations
Obtain the function relation curve of junction temperature and saturation voltage drop.
S12 determines that elevator starts preceding junction temperature according to the saturation voltage drop of function relation curve and acquisition.
Specifically, saturation voltage drop elevator obtained substitutes into function relation curve, the junction temperature temperature corresponding to saturation voltage drop
Angle value is junction temperature before elevator starts.The saturation voltage drop detected by detection circuit directly measures the junction temperature of IGBT circuits
Value.
In one embodiment, as shown in fig. 6, determining that the variations injunction temperature value of tested point includes the following steps according to load value
S602 to S604：
S602 obtains variations injunction temperature curve when elevator is run under different loads value.
The variations injunction temperature curve that elevator is run under different loads value can be when elevator is run under maximum load value
Operation when under the variations injunction temperature curve or other load values when variations injunction temperature curve, elevator are run under minimum load value is bent
Line.The preferred elevator load value of the present embodiment is 100%, 50% and 0%.
Specifically, the variations injunction temperature curve of the IGBT when elevator load is 100% is obtained.First according to step S11-S12
Measure junction temperature Tj0 before elevator starts.The operation curve of elevator is divided into several moment points according to the time, as t1,
t2…….It is measurement point to choose a moment point, and it is measurement point such as to choose the t1 moment.Elevator is started with 100% load value and is transported
Row stops elevator operation when operation is to the t1 moment, measures the saturation voltage drop of the IGBT after applying constant current immediately, will survey
In the function relation curve of junction temperature and saturation voltage drop that the saturation voltage drop obtained substitutes into, the junction temperature tj1 at the t1 moment is obtained.When t1
The variations injunction temperature value △ tj1 at quarter are that the junction temperature tj1 at t1 moment subtracts junction temperature Tj0 before startup.If the selection t2 moment is measurement point,
The variations injunction temperature value △ tj2 at t2 moment are obtained likewise, repeating the above steps.It repeats the above steps, until obtaining elevator operation
The variations injunction temperature value of all moment points on curve determines elevator in 100% time fortune of load value according to variations injunction temperature value and moment point
Variations injunction temperature curve when row.
It is identical, elevator load value is changed, the acquisition elevator that repeats the above steps is 50% in load value and load value is
Variations injunction temperature curve when 0% time operation.Principle is identical, and details are not described herein.
S604, according under different loads value run when variations injunction temperature curve determine elevator the load value tested point
Variations injunction temperature value.
Specifically, if you need to measure the junction temperature value of a certain moment point in running process of elevator in real time.First, according to step S11-
S12 obtains junction temperature before the startup before elevator starts operation.Secondly, it obtains elevator and starts the load value before operation, if elevator starts
Load value before operation is 100%, since step S602 has obtained variations injunction temperature curve when elevator load value is 100%,
It can directly determine variations injunction temperature curve, the junction temperature that a certain moment point for needing to measure can be obtained according to variations injunction temperature curve becomes
Variations injunction temperature value is added the junction temperature value that can obtain a certain moment point for needing to measure by change value with junction temperature before startup.
If it is 30% that elevator, which starts the load value before operation, since the step S602 variations injunction temperature curves obtained in advance are
100%, 50% and 0%, without load value be 30% when variations injunction temperature curve.Due to the controlling party of elevator under different loads
Formula is constant but output current is different, i.e. the switching losses of IGBT are consistent, and conducting consume is different.So the variations injunction temperature of IGBT
It is directly proportional to load variation, you can the load value before operation is started according to elevator and determines that the junction temperature to be fitted for needing to be fitted becomes
Change curve, the variations injunction temperature curve for the load value that current elevator starts before operation gone out according to variations injunction temperature curve matching to be fitted,
The variations injunction temperature value at a certain moment that needs measure is obtained further according to the variations injunction temperature curve fitted, you can acquisition needs to measure
The a certain moment junction temperature value.
Specifically, as shown in fig. 7, to be fitted the curve synoptic diagram of variations injunction temperature curve.First, as shown in fig. 7, elevator
The operation curve of elevator is divided into several moment points, such as t1, t2 ... by operation curve 701 according to the time.Curve 702 is
Variations injunction temperature curve of the elevator when 50% loads, wherein variations injunction temperature value of the curve 702 at the t2 moment is △ Tj2.Curve 704
For variations injunction temperature curve of the elevator when 0% loads, wherein variations injunction temperature value of the curve 704 at the t2 moment is △ Tj1.As needed
The junction temperature value at t2 moment when elevator load value is 30% is measured, first, when can determine 50% load according to load value 30%
Variations injunction temperature curve 704 when variations injunction temperature curve 702 and 0% loads is variations injunction temperature curve to be fitted.According to 702 He of curve
Variations injunction temperature of the curve 704 this two when being fitted variations injunction temperature curve matching elevator and running to t2 moment and load value 30% is bent
Line 703, and variations injunction temperature value of the curve 703 at the t2 moment is △ Tj3.
The variations injunction temperature value at t2 moment is △ Tj1 when due to load value being 0%, the junction temperature at t2 moment when load value is 50%
Changing value is △ Tj2, since the variations injunction temperature of synchronization different loads increases in proportion,
So the variations injunction temperature value △ Tj3 at t1 moment are when load value is 30%：
The variations injunction temperature value △ Tj3 got are added with junction temperature before startup when can be obtained elevator load 30% in t2
The junction temperature value at quarter.
If the variations injunction temperature curve load that step S602 is obtained in advance is respectively 90%, 60%, 20%, then according to load value
30% determine wait be fitted variations injunction temperature curve be load value be 60% and 20% when variations injunction temperature curve.As needed to measure
Elevator load value is 70%, then can determine that the variations injunction temperature curve that load value is 90% and 60% is to wait for according to load value 70%
It is fitted variations injunction temperature curve.In order to ensure directly to determine variations injunction temperature curve to be fitted, step according to elevator actual loading value
The variations injunction temperature curve run under the different loads value that S602 is obtained in advance is preferentially chosen under maximum load and is transported under minimum load
Capable variations injunction temperature curve.
By micro-current circuit occurs for above-mentioned elevator frequency converter IGBT detection devices and method before elevator starts to IGBT
Apply constant current, the saturation voltage drop after detection circuit measurement IGBT circuits application constant current is sent to controller, controller
The junction temperature of elevator before activation is determined according to saturation voltage drop.Above-mentioned apparatus and method can directly measure IGBT by detection circuit
Saturation voltage drop, the junction temperature of determining elevator is removed further according to saturation pressure, banned tradition by measure IGBT shell temperature go to estimate
The method of junction temperature, realizing can junction temperature value that is direct, accurately measuring IGBT.
It should be understood that although each step in the flow chart of Fig. 4-6 is shown successively according to the instruction of arrow,
These steps are not that the inevitable sequence indicated according to arrow executes successively.Unless expressly stating otherwise herein, these steps
Execution there is no stringent sequences to limit, these steps can execute in other order.Moreover, at least one in Fig. 4-6
Part steps may include that either these sub-steps of multiple stages or stage are not necessarily in synchronization to multiple sub-steps
Completion is executed, but can be executed at different times, the execution sequence in these sub-steps or stage is also not necessarily successively
It carries out, but can either the sub-step of other steps or at least part in stage be in turn or alternately with other steps
It executes.
In one embodiment, a kind of computer equipment is provided, which can be controller, internal junction
Composition can be as shown in Figure 8.The computer equipment include the processor connected by system bus, memory, network interface and
Database.Wherein, the processor of the computer equipment is for providing calculating and control ability.The memory packet of the computer equipment
Include non-volatile memory medium, built-in storage.The non-volatile memory medium is stored with operating system, computer program and data
Library.The built-in storage provides environment for the operation of operating system and computer program in non-volatile memory medium.The calculating
The database of machine equipment is for storing data.The network interface of the computer equipment is used to pass through network connection with external terminal
Communication.To realize a kind of elevator frequency converter IGBT junction temperature online test methods when the computer program is executed by processor.
It will be understood by those skilled in the art that structure shown in Fig. 8, is only tied with the relevant part of application scheme
The block diagram of structure does not constitute the restriction for the computer equipment being applied thereon to application scheme, specific computer equipment
May include either combining certain components than more or fewer components as shown in the figure or being arranged with different components.
In one embodiment, a kind of computer equipment, including memory and processor are provided, is stored in memory
Computer program, the processor realize following steps when executing computer program：
It controls micro-current and circuit occurs to IGBT circuits application constant current.
It controls detection circuit and measures the saturation voltage drop after IGBT circuits application constant current.
Junction temperature value is determined according to saturation voltage drop.
In one embodiment, following steps are also realized when processor executes computer program：
It obtains the load value of elevator and elevator starts preceding junction temperature.
The variations injunction temperature value of tested point is determined according to load value.
Junction temperature and the variations injunction temperature value of tested point obtain the junction temperature value of tested point before being started according to elevator.
In one embodiment, following steps are also realized when processor executes computer program：
Obtain variations injunction temperature curve when elevator is run under most different load values；
Determine that elevator becomes in the junction temperature of the tested point of load value according to variations injunction temperature curve when being run under different loads value
Change value.
In one embodiment, a kind of computer readable storage medium is provided, computer program is stored thereon with, is calculated
Machine program realizes following steps when being executed by processor：
It controls micro-current and circuit occurs to IGBT circuits application constant current.
Control detection circuit measures IGBT circuits and applies the saturation voltage drop after the constant current.
Junction temperature value is determined according to saturation voltage drop.
In one embodiment, following steps are also realized when computer program is executed by processor：
It obtains the load value of elevator and elevator starts preceding junction temperature.
The variations injunction temperature value of tested point is determined according to load value.
Junction temperature and the variations injunction temperature value of tested point obtain the junction temperature value of tested point before being started according to elevator.
In one embodiment, following steps are also realized when computer program is executed by processor：
Obtain variations injunction temperature curve when elevator is run under most different load values；
Determine that elevator becomes in the junction temperature of the tested point of load value according to variations injunction temperature curve when being run under different loads value
Change value.
One of ordinary skill in the art will appreciate that realizing all or part of flow in above-described embodiment method, being can be with
Relevant hardware is instructed to complete by computer program, the computer program can be stored in a non-volatile computer
In read/write memory medium, the computer program is when being executed, it may include such as the flow of the embodiment of above-mentioned each method.Wherein,
Any reference to memory, storage, database or other media used in each embodiment provided herein,
Including non-volatile and/or volatile memory.Nonvolatile memory may include read-only memory (ROM), programming ROM
(PROM), electrically programmable ROM (EPROM), electrically erasable ROM (EEPROM) or flash memory.Volatile memory may include
Random access memory (RAM) or external cache.By way of illustration and not limitation, RAM is available in many forms,
Such as static state RAM (SRAM), dynamic ram (DRAM), synchronous dram (SDRAM), double data rate sdram (DDRSDRAM), enhancing
Type SDRAM (ESDRAM), synchronization link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM
(RDRAM), direct memory bus dynamic ram (DRDRAM) and memory bus dynamic ram (RDRAM) etc..
Each technical characteristic of above example can be combined arbitrarily, to keep description succinct, not to above-described embodiment
In each technical characteristic it is all possible combination be all described, as long as however, the combination of these technical characteristics be not present lance
Shield is all considered to be the range of this specification record.
The several embodiments of the application above described embodiment only expresses, the description thereof is more specific and detailed, but simultaneously
It cannot therefore be construed as limiting the scope of the patent.It should be pointed out that coming for those of ordinary skill in the art
It says, under the premise of not departing from the application design, various modifications and improvements can be made, these belong to the protection of the application
Range.Therefore, the protection domain of the application patent should be determined by the appended claims.
Claims (10)
1. a kind of elevator frequency converter IGBT junction temperature on-line measuring devices, including：
Circuit occurs for the micro-current being connect with IGBT circuits, for applying constant current to IGBT circuits；
The detection circuit being connect with the IGBT circuits, for measuring the saturation after the IGBT circuits apply the constant current
Pressure drop；
The controller being connect with the detection circuit, for determining junction temperature value according to the saturation voltage drop；
The IGBT circuits are isolated and the isolation circuit of circuit occurs for the detection circuit, micro-current.
2. elevator frequency converter IGBT junction temperature on-line measuring devices according to claim 1, which is characterized in that the micro-current
It includes the constant-current source that input terminal is connect with power supply, output end is connect with the IGBT circuits that circuit, which occurs,.
3. elevator frequency converter IGBT junction temperature on-line measuring devices according to claim 1, which is characterized in that the detection electricity
Road includes the first subtracter and the second subtracter；
The in-phase input end of first subtracter connects the output end of constant-current source, reverse input end connects the IGBT circuits,
Output end connects the reverse input end of second subtracter；
The noninverting input of second subtracter connects the IGBT circuits, output end connects the controller.
4. elevator frequency converter IGBT junction temperature on-line measuring devices according to claim 3, which is characterized in that the detection electricity
Road further includes the first follower and the second follower；
The in-phase input end of first follower connects the output end of the constant-current source；The anti-phase input of first follower
End connects the output end of first follower；The output end of first follower connects the in the same direction defeated of first subtracter
Enter end；The inverting input of second follower connects the output end of second follower；Second follower it is defeated
Outlet connects the noninverting input and reverse input end of the reverse input end of first subtracter, the second subtracter.
5. elevator frequency converter IGBT junction temperature on-line measuring devices according to claim 4, which is characterized in that the isolation electricity
Road includes the first diode and the second diode；
The anode of first diode connects the output end of the constant-current source；The cathode connection described the of first diode
The in-phase input end of two followers；The anode of second diode connects the in-phase input end of second follower；It is described
The anode of second diode connects the IGBT circuits.
6. elevator frequency converter IGBT junction temperature on-line measuring devices according to claim 1, which is characterized in that described device is also
It include the contactor being connect with IGBT circuits.
7. elevator frequency converter IGBT junction temperature on-line measuring devices according to claim 1, which is characterized in that the controller
It is additionally operable to obtain the load value of elevator and elevator starts preceding junction temperature；The variations injunction temperature value of tested point is determined according to the load value；
The junction temperature value of tested point is obtained according to junction temperature before the startup and the variations injunction temperature value of tested point.
8. a kind of elevator frequency converter IGBT junction temperature online test methods, run on control as described in any one of claim 1 to 7
Device, which is characterized in that the method step includes：
It controls micro-current and circuit occurs to IGBT circuits application constant current；
Control detection circuit measures the IGBT circuits and applies the saturation voltage drop after the constant current；
Junction temperature value is determined according to the saturation voltage drop.
9. elevator frequency converter IGBT junction temperature online test methods according to claim 8, which is characterized in that described according to institute
Stating the step of saturation voltage drop determines junction temperature value includes：
It obtains the load value of elevator and elevator starts preceding junction temperature；
The variations injunction temperature value of tested point is determined according to the load value；
Junction temperature and the variations injunction temperature value of tested point obtain the junction temperature value of tested point before being started according to the elevator.
10. elevator frequency converter IGBT junction temperature online test methods according to claim 9, which is characterized in that the basis
The load value determines that the step of variations injunction temperature value of tested point includes：
Obtain variations injunction temperature curve when elevator is run under different loads value；
The knot of tested point of the elevator in the load value is determined according to variations injunction temperature curve when being run under the different loads value
Warm changing value.
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| CN110726921A (en) * | 2019-11-14 | 2020-01-24 | 臻驱科技（上海）有限公司 | IGBT module service life monitoring method |
| CN112268637A (en) * | 2020-09-23 | 2021-01-26 | 北京首钢自动化信息技术有限公司 | Temperature fault early warning device for frequency conversion equipment |
| CN115166459A (en) * | 2022-06-28 | 2022-10-11 | 中国第一汽车股份有限公司 | Junction temperature detection device, junction temperature detection method, electronic equipment and storage medium |
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