CN209542771U - A kind of IGBT module parallel temperature sensing circuit - Google Patents
A kind of IGBT module parallel temperature sensing circuit Download PDFInfo
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- CN209542771U CN209542771U CN201920074196.7U CN201920074196U CN209542771U CN 209542771 U CN209542771 U CN 209542771U CN 201920074196 U CN201920074196 U CN 201920074196U CN 209542771 U CN209542771 U CN 209542771U
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Abstract
The utility model is specifically related to a kind of IGBT module parallel temperature sensing circuit, and the NTC resistance of IGBT module in parallel is distinguished resistance series connection partial pressure including bleeder circuit and exports two groups of IGBT module temperature signal voltage values；Two groups of temperature signal voltage values are compared and select high temperature signal state by comparator circuit, by high temperature signal state transfer to analog switching circuit；The high signal voltage value of temperature is transported to sampling again and follows conditioning circuit by analog switching circuit.By the high signal voltage value of the temperature after over-sampling follows conditioning circuit by pressing streamline sexual isolation conversion circuit the electric current of ratios such as to be converted into, current value is finally converted into the analog voltage of an A/D processing for DSP by conditioning output circuit again.The temperature that this method can solve latter two in parallel module of IGBT can obtain seldom all the way sample circuit, seldom account for DSP sampling resource situation under carry out real-time monitoring.
Description
Technical field
The invention belongs to power electronics fields, and in particular to a kind of IGBT module parallel temperature sensing circuit.
Background technique
IGBT is widely used in novel Technics of Power Electronic Conversion field, and in IGBT module application technology, most critical
Parameter first is that the temperature of igbt chip, IGBT module enclosed inside has temperature sensor (NTC) mostly at present, in this way for
The detection and protection of IGBT temperature provide more reliable scheme.With the continuous promotion of the power grade of power electronic equipment, drop
The increasing limitation that low cost requires, IGBT parallel arrangement obtains more uses of industry, however limited temperature sample circuit cost
And the requirement in space, temperature detection only is carried out to a single module in parallel IGBT scheme mostly in existing industry, or increase by one
Road samples cost, and the temperature detection of two modules is done in compressor circuit space.
Above two detection scheme has following several disadvantages: 1) only carrying out temperature detection to a single module, lead to parallel connection
Another module temperature detection be in runaway condition；2) increase and sample all the way, because to current IGBT temperature detection safety, resisting
Equal requirements use isolation detection scheme to electromagnetic interference capability by force, can more sampling costs all the way, three-phase IGBT circuit is just naturally more
Three tunnels；3) due to limited space, electric circuit electronics technical interelement space will be reduced in the case where space can not be increased, and increase by three tunnels
Sampling processing conditioning circuit is having apparent increase to electromagnetic interference and detection response time etc..
Summary of the invention
1. technical problem to be solved:
For the above technical issues, the present invention proposes a kind of IGBT module parallel temperature sensing circuit；This circuit is to use
Single channel isolation sample circuit, but can be realized the temperature detection of two IGBT parallel connections.It will by hardware circuit in this method
Two IGBT temperatures are converted into voltage value, and the high voltage value of temperature is transmitted to over-sampling modulate circuit.It had both been able to satisfy two in this way
IGBT temperature can detect, also quickly can judge that the high value of temperature is transported to sample circuit by hardware.So as to fast
Speed is monitored to the temperature of IGBT and carries out corresponding safeguard measure, further improves equipment operational reliability.
2. technical solution:
A kind of IGBT module parallel temperature sensing circuit, the temperature of the IGBT module for detecting two-way parallel connection, feature
It is: follows conditioning circuit, pressure streamline sexual isolation conversion electricity including bleeder circuit, comparator circuit, analog switching circuit, sampling
Road improves output circuit.
The NTC resistance of two IGBT modules in parallel is connected partial pressure simultaneously by the bleeder circuit with a fixed resistance respectively
Export two groups of IGBT module temperature signal voltage values in parallel.
Two groups of temperature signal voltage values of input are compared and select wherein high temperature signal state by comparator circuit,
And by high temperature signal state transfer to analog switching circuit, to control the selector channel of analog switch；Analog switch electricity
The high signal voltage value of temperature is transported to sampling again and follows conditioning circuit by road.
The high signal voltage value of temperature after over-sampling follows conditioning circuit is passed through into pressure streamline sexual isolation conversion circuit
It the electric current of ratios such as is converted into, current value is finally converted by the mould that an A/D for DSP is handled by conditioning output circuit again
Quasi- voltage value.
Further, the bleeder circuit, comparator circuit and analog switching circuit physical circuit are as follows: the partial pressure electricity
Road are as follows: NTC resistance R1 connects to obtain voltage value TEMP_1 with divider resistance R6, and NTC resistance R2 connects to obtain with divider resistance R7
Voltage value TEMP_2；Circuit NTC resistance terminal after series connection is connected to power supply, divider resistance end ground connection.
The comparator circuit specifically: transmit bleeder circuit collection voltages value TEMP_1, voltage value TEMP_2 respectively
To differential comparator U1 first, third input port；6 foot phases of the 4th delivery outlet of differential comparator U1 and analog switch U2
Even.
The analog switching circuit specifically: 1 foot of analog switch U2 connects voltage value TEMP_2, the third of analog switch
Foot connects voltage value TEMP_1;4th foot of the analog switch exports the voltage value TEMP_12 filtered out.
Further, the sampling follows conditioning circuit, presses streamline sexual isolation conversion circuit, and conditioning output circuit is specifically electric
Road are as follows: the voltage value TEMP_12 filtered out is connected to the 1 foot anode input of operational amplifier U3, and 3 feet of operational amplifier U3 are negative
End is connected to the formation of 4 foot output ends and follows circuit；One end is connected to after the 4 foot output ends of operational amplifier U3 are connected with resistance R9
3 feet of light-coupled isolation chip D1, the other end connect 3 feet of operational amplifier U4；Capacitor C1 is attempted by 3 feet of operational amplifier U4
On 4 feet；4 foot series resistor R8 of operational amplifier U4 output pin is connected to 1 foot of light-coupled isolation chip D1；Light-coupled isolation chip
6 feet and 5 feet of D1 are connected on 3 feet and 1 foot of operational amplifier U5；Resistance R10 and the logical C2 of capacitor are parallel to operation and put
3,4 foot of input/output terminal of big device U5 forms negative-feedback circuit；4 foot of output pin of operational amplifier U5 connects resistance R11, capacitor
Final output current value after C3 filtering.
Further, the differential comparator U1D model TL331KDBVR；The model of analog switch U2
SN74LVC1G3157；Operational amplifier U3, operational amplifier U4 and operational amplifier U5 model are rail-to-rail output operation
Amplifier LMV321M5；The model HCNR201 of light-coupled isolation chip D1.
3. the utility model has the advantages that
(1) it can obtain seldom adopting all the way using the temperature that after this programme, can solve IGBT latter two module in parallel
Sample circuit, seldom account for DSP sampling resource situation under carry out real-time monitoring, also can under abnormality rapid starting protection mechanism,
To reach the condition for validity protected by temperature to IGBT.
(2) this circuit arrangement in the case where not modifying any circuit parameter while could be used that temperature in single IGBT
Detection is equivalent to 0V input, the partial pressure value all the way of access because bleeder circuit only has ground resistance when not connecing vacantly all the way
Surely it is greater than 0V, is equivalent to this road voltage and is higher than and do not connect all the way, therefore the voltage value for being transferred to sample circuit is inevitable with regard to this road temperature
The voltage value of conversion.
Detailed description of the invention
Fig. 1 is the temperature screening circuit in the present invention；
Fig. 2 is the sample circuit in the present invention.
Specific embodiment
The present invention is specifically described with reference to the accompanying drawing.
A kind of IGBT module parallel temperature sensing circuit, the temperature of the IGBT module for detecting two-way parallel connection, feature
It is: follows conditioning circuit, pressure streamline sexual isolation conversion electricity including bleeder circuit, comparator circuit, analog switching circuit, sampling
Road improves output circuit.Wherein bleeder circuit, comparator circuit, analog switching circuit are that temperature as shown in Fig. 1 screens electricity
Road；Sampling follows conditioning circuit, presses streamline sexual isolation conversion circuit, improves output circuit.For sampling electricity as shown in Fig. 2
Road.
The NTC resistance of two IGBT modules in parallel is connected partial pressure simultaneously by the bleeder circuit with a fixed resistance respectively
Export two groups of IGBT module temperature signal voltage values in parallel.
Two groups of temperature signal voltage values of input are compared and select wherein high temperature signal state by comparator circuit,
And by high temperature signal state transfer to analog switching circuit, to control the selector channel of analog switch；Analog switch electricity
The high signal voltage value of temperature is transported to sampling again and follows conditioning circuit by road.
The high signal voltage value of temperature after over-sampling follows conditioning circuit is passed through into pressure streamline sexual isolation conversion circuit
It the electric current of ratios such as is converted into, current value is finally converted by the mould that an A/D for DSP is handled by conditioning output circuit again
Quasi- voltage value.
Present invention employs method be that circuit is divided into two major parts i.e.: temperature screening circuit and sample circuit.
Fixed resistance is connected in series in the NTC of parallel IGBT by temperature screening circuit respectively, will be warm by series resistance partial pressure
Angle value is converted into voltage value.Due to the characteristic of NTC, i.e., rises resistance with temperature and have exponent relation reduction, with negative temperature coefficient
Thermistor phenomenon and material.It may be designed on bleeder circuit, temperature value is higher, and corresponding voltage value is higher.Pass through
Two groups of voltage values that partial pressure obtains are controlled by comparator is transported to sample circuit for high voltage value, needs exist for two devices
Part: a device is comparator, model TL331KDBVR.Such as the A module and B module of parallel IGBT, the temperature ratio B's of A
Height, comparator output are high.If the temperature ratio B's of A is low, comparator output is low.Thus obtain an output control signal, high electricity
Flat is exactly the temperature height of A, and low level is exactly that the temperature of B is high；Another device is exactly a channel 2:1 analog switch, model
SN74LVC1G3157.The output signal of comparator is connected to by channel selecting foot.The voltage value of A is transported to when high level
The voltage value of B is transported to sample circuit when low level by sample circuit.It can directly allow temperature high by the two devices
Voltage value is transported to sample circuit, and IGBT operation irregularity is judged by software sampling calculating without two sample circuits
Caused temperature, which is higher than, works normally threshold value.
Sample circuit is a kind of analog voltage Acquisition Circuit of band isolation；The temperature transition voltage value of acquisition is passed through into tune
Reason, isolation circuit export to obtain the analogue value (can also select other MCU applicatory) that an A/D for DSP is handled.This
In be also required to two devices: a device is track to track high-operational amplifier, model LMV321M5.For doing analog voltage
Filtering, conditioning obtain the value range that can be sampled.By taking DSP as an example, the analog channel input value of DSP is 0 ~ 3VDC value.So
The highest virtual value of temperature can be corresponded to the sampled value of 3VDC.Another device is exactly linear optical coupling isolation chip, model
HCNR201.Influence for electromagnetic interference, ambient noise for reducing high power device etc. to detection circuit, it is ensured that measurement result
Accuracy, often by circuit-under-test with test circuit be electrically isolated.So sampling isolation circuit is using high-precision
Isolation scheme.
Further, the bleeder circuit, comparator circuit and analog switching circuit physical circuit are as follows: the partial pressure electricity
Road are as follows: NTC resistance R1 connects to obtain voltage value TEMP_1 with divider resistance R6, and NTC resistance R2 connects to obtain with divider resistance R7
Voltage value TEMP_2；Circuit NTC resistance terminal after series connection is connected to power supply, divider resistance end ground connection.Such as R1 in Fig. 1 bleeder circuit
It is respectively the NTC thermistor of parallel IGBT with R2, R6 and R7 are the 1K Ω patch thick-film resistor of precision 1%, the resistance of R6 and R7
Value is mainly according to corresponding NTC in a reference value that alterable or detectable temperature range corresponds to resistance and chooses.Benchmark
The voltage precision prescribed of power supply 5VREF is higher, cannot occur rising because of the variation of load resistor value, voltage value and fall phenomenon.
R1, which connects to divide with R6, is connected to voltage value TEMP_1, and R2, which connects to divide with R7, waits until voltage value TEMP_2.For example: according to
NTC characteristic, if the same operation time temperature of the corresponding IGBT of R1 is higher than the corresponding IGBT of R2, then the resistance value of R1 is necessarily low
The voltage value of net point TEMP_1 is higher than net point TEMP_2 in R2, figure.
The comparator circuit specifically: transmit bleeder circuit collection voltages value TEMP_1, voltage value TEMP_2 respectively
To differential comparator U1 first, third input port；6 foot phases of the 4th delivery outlet of differential comparator U1 and analog switch U2
Even.Single channel differential comparator U1, model TL331KDBVR, small in size, fast response time are selected in comparator circuit.According to this
Chip operation instruction, if input voltage value IN- ratio IN+ high, comparator output is low；If IN+ ratio IN- high, compares
Device output is height.TEMP_1 is concatenated into 3 feet of comparator U1 by resistance R5, and TEMP_2 is concatenated into comparator U1 by resistance R4
1 foot, 4 feet of U1 are pulled upward to power supply 5VA1 by R3, and 5 feet meet power supply 5VA1, and 2 feet meet power ground AGND1.The above example, TEMP_
1 voltage value is higher than TEMP_2, i.e. IN+ ratio IN- high, then U1 output (4 foot) is high level.
The analog switching circuit specifically: 1 foot of analog switch U2 connects voltage value TEMP_2, the third of analog switch
Foot connects voltage value TEMP_1;4th foot of the analog switch exports the voltage value TEMP_12 filtered out.Analog switching circuit
Middle selection one channel 2:1 analog switch U2, model SN74LVC1G3157.Small in size, single-pole double throw switch speed is fast.According to
The chip operation instruction, when channel selecting foot S(6 foot) be high level when, B2(1 foot) with output pin A(4 foot) be connected to；Work as channel
Select foot S(6 foot) for low level when, B1(1 foot) with output pin A(4 foot) be connected to.The 6 foot S of control foot of U2 is connected to the output of U1
1 foot B2, the R2 and R7 series connection partial pressure value TEMP_2 that 4 foot of foot, R1 and R6 series connection partial pressure value TEMP_1 are connected to U2 is connected to the 3 of U2
The 4 foot A of output pin of foot B1, U2 are that 5 feet of the voltage value TEMP_12, U2 that filter out are connected to power supply 5VA1, and 2 feet connect power ground
AGND1.The above example, TEMP_1 connection B2, TEMP_2 connection B1, comparator U1 export 4 feet (4 foot) connection S.S is height, then
TEMP_1 is connected to output pin.Therefore the high voltage value of the corresponding IGBT temperature of R1 is obtained into screening and is finally transported to sample circuit.
Further, the sampling follows conditioning circuit, presses streamline sexual isolation conversion circuit, and conditioning output circuit is specifically electric
Road are as follows: the voltage value TEMP_12 filtered out is connected to the 1 foot anode input of operational amplifier U3, and 3 feet of operational amplifier U3 are negative
End is connected to the formation of 4 foot output ends and follows circuit；One end is connected to after the 4 foot output ends of operational amplifier U3 are connected with resistance R9
3 feet of light-coupled isolation chip D1, the other end connect 3 feet of operational amplifier U4；Capacitor C1 is attempted by 3 feet of operational amplifier U4
On 4 feet；4 foot series resistor R8 of operational amplifier U4 output pin is connected to 1 foot of light-coupled isolation chip D1；Light-coupled isolation chip
6 feet and 5 feet of D1 are connected on 3 feet and 1 foot of operational amplifier U5；Resistance R10 and the logical C2 of capacitor are parallel to operation and put
3,4 foot of input/output terminal of big device U5 forms negative-feedback circuit；4 foot of output pin of operational amplifier U5 connects resistance R11, capacitor
Final output current value after C3 filtering.
Sampling follows amplifier U3, U4 model rail-to-rail output operational amplifier LMV321M5 in conditioning circuit, small in size,
Precision is high.Analog voltage TEMP_12 is directly connected to the 1 foot anode input of U3, and 3 foot negative terminals are connected to 4 foot output ends and are formed
Circuit is followed, output voltage values are equal to input value.
Streamline sexual isolation conversion circuit is pressed, light-coupled isolation chip model HCNR201, the chip is by high-performance light-emitting diodes
Pipe LED and photodiode PD1 and PD2 with stringent proportionate relationship are constituted, and light-coupled isolation chip HCNR201 is former
Reason figure is as shown in Fig. 2.One end is connected to 3 feet of D1 after the 4 feet output series connection R9 of U3, and the other end connects 3 feet of U4, and C1 simultaneously connects
In outputting and inputting on foot for U4.4 foot series resistor R8 of U4 output pin is connected to 1 foot of U1.LED issue light by PD1,
PD2 is received, and wherein PD2 is for generating output electric current；PD1 is used for servo feedback, by amplifier U4 to light-emitting LED
Conducting electric current is compensated by, and improves the linear and temperature characterisitic between input and output circuit, such a construction ensures linear optical couplings
High stability and high linearity.Compensating electric capacity C1 is used for electric in improving circuit stability, reduction circuit output noise and limitation
The bandwidth of operation on road.Sample input value TEMP_12 obtains PD1 current value divided by R9, and PD2 and PD1 is closed at stringent ratio
System, same IPD2 obtain current value in proportion.
The electric current for obtaining linear isolation optocoupler PD2 in conditioning output circuit, i.e. the 5 of U1,6 feet are connected respectively to negative-feedback
3,4 foot of input/output terminal that 1,3 feet of fortune hair U5, R10 and C2 are parallel to operation U5 forms negative-feedback circuit, the output pin 4 of U5
Foot connect R11, C3 filtering after final output, current value multiplied by resistance R10 obtain final output to DSP A/D Sampling Interface.Electricity
C2, R11, C3 are equally used in improvement circuit stability, reduce circuit output noise in road.
Although the present invention has been described by way of example and in terms of the preferred embodiments, they be not it is for the purpose of limiting the invention, it is any ripe
This those skilled in the art is practised, without departing from the spirit and scope of the invention, can make various changes or retouch from working as, therefore guarantor of the invention
Shield range should be subject to what claims hereof protection scope was defined.
Claims (4)
1. a kind of IGBT module parallel temperature sensing circuit, the temperature of the IGBT module for detecting two-way parallel connection, feature exist
In: conditioning circuit, pressure streamline sexual isolation conversion electricity are followed including bleeder circuit, comparator circuit, analog switching circuit, sampling
Road improves output circuit；
The NTC resistance of two IGBT modules in parallel is connected with a fixed resistance respectively and divides and export by the bleeder circuit
Two groups of IGBT module temperature signal voltage values in parallel；
Two groups of temperature signal voltage values of input are compared the wherein high temperature signal state that selects by comparator circuit, and will
High temperature signal state transfer is to analog switching circuit, to control the selector channel of analog switch；Analog switching circuit is again
The high signal voltage value of temperature is transported to sampling and follows conditioning circuit；
The high signal voltage value of temperature after over-sampling follows conditioning circuit is passed through into pressure streamline sexual isolation conversion circuit conversion
For the electric current of equal ratios, current value is finally converted by the simulation electricity that an A/D for DSP is handled by conditioning output circuit again
Pressure value.
2. a kind of IGBT module parallel temperature sensing circuit according to claim 1, it is characterised in that: the partial pressure electricity
Road, comparator circuit and analog switching circuit physical circuit are as follows: the bleeder circuit are as follows: NTC resistance R1 and divider resistance R6
Series connection obtains voltage value TEMP_1, and NTC resistance R2 connects to obtain voltage value TEMP_2 with divider resistance R7；Circuit after series connection
NTC resistance terminal is connected to power supply, divider resistance end ground connection；
The comparator circuit specifically: bleeder circuit collection voltages value TEMP_1, voltage value TEMP_2 are transmitted separately to difference
Dynamic comparator U1 first, third input port；The 4th delivery outlet of differential comparator U1 is connected with 6 feet of analog switch U2；
The analog switching circuit specifically: 1 foot of analog switch U2 connects voltage value TEMP_2, and the third foot of analog switch connects
Meet voltage value TEMP_1;4th foot of the analog switch exports the voltage value TEMP_12 filtered out.
3. a kind of IGBT module parallel temperature sensing circuit according to claim 2, it is characterised in that: the sampling follows
Conditioning circuit presses streamline sexual isolation conversion circuit, improves output circuit physical circuit are as follows: the voltage value TEMP_12 filtered out connects
It is connected to the 1 foot anode input of operational amplifier U3, the 3 foot negative terminals of operational amplifier U3 are connected to the formation of 4 foot output ends and follow electricity
Road；One end is connected to 3 feet of light-coupled isolation chip D1, the other end after the 4 foot output ends of operational amplifier U3 are connected with resistance R9
Connect 3 feet of operational amplifier U4；Capacitor C1 is attempted by 3 feet and 4 feet of operational amplifier U4；Operational amplifier U4 output pin
4 foot series resistor R8 are connected to 1 foot of light-coupled isolation chip D1；6 feet and 5 feet of light-coupled isolation chip D1 are connected to operation
On 3 feet and 1 foot of amplifier U5；3,4 foot of input/output terminal that resistance R10 and the logical C2 of capacitor are parallel to operational amplifier U5 is formed
Negative-feedback circuit；4 foot of output pin of operational amplifier U5 connects resistance R11, final output current value after capacitor C3 filtering.
4. a kind of IGBT module parallel temperature sensing circuit according to claim 3, it is characterised in that: the differential comparison
Device U1D model TL331KDBVR；The model SN74LVC1G3157 of analog switch U2；Operational amplifier U3, operation amplifier
Device U4 model and operational amplifier U5 are rail-to-rail output operational amplifier LMV321M5；The model of light-coupled isolation chip D1
For HCNR201.
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| CN201920074196.7U CN209542771U (en) | 2019-01-17 | 2019-01-17 | A kind of IGBT module parallel temperature sensing circuit |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109581180A (en) * | 2019-01-17 | 2019-04-05 | 南京亚派科技股份有限公司 | A kind of IGBT module parallel temperature sensing circuit |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109581180A (en) * | 2019-01-17 | 2019-04-05 | 南京亚派科技股份有限公司 | A kind of IGBT module parallel temperature sensing circuit |
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