CN109001536A - A kind of resistance detection circuit, system and method - Google Patents
A kind of resistance detection circuit, system and method Download PDFInfo
- Publication number
- CN109001536A CN109001536A CN201810575551.9A CN201810575551A CN109001536A CN 109001536 A CN109001536 A CN 109001536A CN 201810575551 A CN201810575551 A CN 201810575551A CN 109001536 A CN109001536 A CN 109001536A
- Authority
- CN
- China
- Prior art keywords
- resistance
- current
- testing
- voltage
- circuit
- 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.)
- Pending
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/08—Measuring resistance by measuring both voltage and current
Abstract
The present invention provides a kind of resistance detection circuit, system and method.The circuit includes D.C. regulated power supply, H-bridge circuit, DC reference control circuit, test point and testing resistance；The D.C. regulated power supply and the DC reference control circuit respectively symmetrically are connected to the both ends of the H-bridge circuit；The H-bridge circuit includes 4 electronic switches, and is bridged by the testing resistance；The test point includes voltage detecting point and current detecting point, wherein the voltage detecting point is used to detect the voltage at the testing resistance both ends, and the current detecting point is used to detect the loop current of the H-bridge circuit.Circuit of the embodiment of the present invention is simple, can detecte the resistance value of the biggish resistance of resistance value, also can detecte the resistance value of the lesser resistance of resistance value, such as the resistance of TEC, and detection accuracy is high.
Description
Technical field
The present invention relates to circuit detection technique field more particularly to a kind of resistance detection circuits, system and method.
Background technique
Semiconductor cooler (Thermoelectric Cooler, TEC) is common temperature controlling device, TEC in optical device
Resistance value be TEC an important parameter.But since TEC is more sensitive to electric current and TEC resistance value is often very small
(ohm rank), so that the resistance value of TEC seldom can real-time measurement and calculating in use.
Under normal circumstances, the resistance of TEC is detected using dedicated test equipment；However dedicated test equipment valence
Lattice are higher, and it is more complicated to test environmental structure.
Summary of the invention
In view of the problems of the existing technology, the embodiment of the present invention provides a kind of resistance detection circuit, system and side
Method constructs circuit, the system and method for a kind of easy test resistance resistance value, can fast and accurately measuring and calculation resistance.
In a first aspect, the embodiment of the present invention provides a kind of resistance detection circuit, comprising: D.C. regulated power supply, H bridge electricity
Road, DC reference control circuit, test point and testing resistance；
The D.C. regulated power supply and the DC reference control circuit respectively symmetrically are connected to the two of the H-bridge circuit
End；Wherein, the D.C. regulated power supply is used to provide the DC power supply of constant voltage for the H-bridge circuit；The DC reference
Control circuit is used to be arranged the total current in the H-bridge circuit circuit；The H-bridge circuit is for providing low-impedance current loop；
The H-bridge circuit includes 4 electronic switches, and is bridged by the testing resistance；
The test point includes voltage detecting point and current detecting point, wherein the voltage detecting point is described for detecting
The voltage at testing resistance both ends, the current detecting point are used to detect the loop current of the H-bridge circuit.
Further, the test point includes 2 voltage detecting points and 1 current detecting point, wherein the 2 voltage inspection
Measuring point is respectively arranged at two endpoints of the testing resistance bridge joint, and the current detecting point is set to the DC reference control
At the exit point of circuit processed.
Further, the resistance detection circuit further includes reference resistance, the reference resistance and the testing resistance
Series connection；
Correspondingly, the H-bridge circuit is bridged by the testing resistance after series connection with the reference resistance；It is described
2 voltage detecting points are respectively arranged at two endpoints of the testing resistance after series connection and reference resistance bridge joint.
Further, the resistance detection circuit further includes current-limiting resistance；The D.C. regulated power supply series connection limit
The H-bridge circuit is connected to after leakage resistance.
DC reference control circuit described further forms constant-current source by operational amplifier and BJT, is added by DAC control
It is loaded in the voltage of the input terminal of the operational amplifier, so that the DC reference control circuit exports constant current.
A kind of resistance detection circuit provided in an embodiment of the present invention, is controlled by the electronic switch of H-bridge circuit,
Two opposite current loops of current direction can be formed；It can be applied respectively to testing resistance by two current loops contrary
Electric current, and by test point detect testing resistance both ends voltage and loop current, by Ohm's law can be obtained to
The resistance value of measuring resistance.Provided resistance detection circuit through the embodiment of the present invention, circuit is simple, can detecte resistance value compared with
The resistance value of big resistance also can detecte the resistance value of the lesser resistance of resistance value, such as the resistance of TEC, due to H-bridge circuit shape
At the current loop of different flow directions, the characteristic that testing resistance flows through constant current fever in the same direction or refrigeration is effectively avoided, is handed over
Complete loops are constituted for reversed electric current and flow through testing resistance, so that the temperature remains within the normal range for testing resistance, are conducive to improve calculating essence
Degree.
Second aspect, the embodiment of the present invention provide a kind of resistance detection system, including first party of the embodiment of the present invention
Resistance detection circuit described in any embodiment of face and acquisition computing unit；
The acquisition computing unit acquires testing resistance two for the test point based on the resistance detection circuit
The loop current of the voltage at end and the resistance detection circuit, and according to the voltage at the testing resistance both ends and described time
Road electric current calculates the resistance value of the testing resistance.
Further, the test point based on the resistance detection circuit, acquire testing resistance both ends voltage and
The loop current of the resistance detection circuit, and calculated according to the voltage at the testing resistance both ends and the loop current
The resistance value of the testing resistance, specifically includes:
The voltage detecting point of the resistance detection circuit and the number of current detecting point are acquired simultaneously by multi-channel A/D C
According to obtaining the first voltage value of described testing resistance one end, the second voltage value of the testing resistance other end and the electricity
Hinder the loop current of resistance value detection circuit；
The resistance value R of the testing resistance, first formula are calculated by the first formula or the second formula are as follows:
R=(U1-U2)/Iref；
Second formula are as follows:
R=(U1-U2)/Iref-Rref；
Wherein, U1For the first voltage value, U2For second voltage value, and U1>U2, IrefFor loop current, RrefFor with reference to electricity
Resistance.
A kind of resistance detection system provided in an embodiment of the present invention is calculated by resistance detection circuit and acquisition
Unit, automatic to realize that resistance detection calculates, simple and easy to do and precision is high.
The third aspect, the embodiment of the present invention provide a kind of resistance based on resistance detection circuit described in first aspect
Resistance detection method, comprising:
Apply constant current to testing resistance by two opposite current loops of current direction respectively；
When electric current flows through the testing resistance in each current loop, detect respectively the testing resistance both ends voltage and
The loop current of the current loop；
According to the voltage at the testing resistance both ends and the loop current, the measurement resistance value of the testing resistance is obtained.
It is further, described to apply constant current to testing resistance by two opposite current loops of current direction respectively,
It specifically includes:
Two opposite current loops of current direction are constructed by H-bridge circuit, are in series on described two current loops
Testing resistance；
Apply constant current to the H-bridge circuit by described two current loops respectively, so that the electric current flows through
The testing resistance.
Voltage described further according to the testing resistance both ends and the loop current obtain the testing resistance
Resistance value is measured, is specifically included:
Respectively according to the voltage at the testing resistance both ends and the loop current detected every time, pass through the first formula or the
Two formulas calculate the resistance value R of the testing resistance, obtain multiple resistance values of the testing resistance；
The average value for calculating the multiple resistance value, using the average value as the measurement resistance value of the testing resistance；
Wherein, first formula are as follows:
R=(U1-U2)/Iref；
Second formula are as follows:
R=(U1-U2)/Iref-Rref；
Wherein, U1For the first voltage value, U2For second voltage value, and U1>U2, IrefFor loop current, RrefFor with reference to electricity
Resistance.
A kind of resistance detection method provided in an embodiment of the present invention passes through two opposite current loops of current direction
Apply constant current to testing resistance, according to the loop current for the voltage and current loop for detecting testing resistance both ends, obtains
The measurement resistance value of testing resistance.The method of the embodiment of the present invention can detecte the resistance value of the biggish resistance of resistance value, can also examine
The resistance value of the lesser resistance of resistance value, such as the resistance of TEC are surveyed, due to being applied with the electricity of different flow directions on testing resistance
Stream, effectively avoids the characteristic that testing resistance flows through constant current in the same direction fever or refrigeration, alternately inverted electric current flow through to
Measuring resistance is conducive to improve computational accuracy so that the temperature remains within the normal range for testing resistance.
Detailed description of the invention
In order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, to embodiment or will show below
There is attached drawing needed in technical description to be briefly described, it should be apparent that, the accompanying drawings in the following description is this hair
Bright some embodiments for those of ordinary skill in the art without creative efforts, can be with root
Other attached drawings are obtained according to these attached drawings.
Fig. 1 is a kind of resistance detection circuit structure first embodiment schematic diagram of the embodiment of the present invention；
Fig. 2 is a kind of resistance detection circuit structure second embodiment schematic diagram of the embodiment of the present invention；
Fig. 3 is a kind of resistance detecting system schematic diagram of the embodiment of the present invention；
Fig. 4 is a kind of resistance detection method flow diagram of the embodiment of the present invention；
Description of symbols
100, D.C. regulated power supply, 101, H-bridge circuit,
102, DC reference control circuit, 103, test point,
104, testing resistance, 105, electronic switch,
106, reference resistance, 107, current-limiting resistance.
Specific embodiment
In order to make the object, technical scheme and advantages of the embodiment of the invention clearer, below in conjunction with the embodiment of the present invention
In attached drawing, technical solution in the embodiment of the present invention is explicitly described, it is clear that described embodiment is the present invention
A part of the embodiment, instead of all the embodiments.Based on the embodiments of the present invention, those of ordinary skill in the art are not having
Every other embodiment obtained under the premise of creative work is made, shall fall within the protection scope of the present invention.
Fig. 1 is a kind of resistance detection circuit structure first embodiment schematic diagram of the embodiment of the present invention, as shown in Figure 1
Resistance detection circuit, comprising: D.C. regulated power supply 100, H-bridge circuit 101, DC reference control circuit 102, test point
103 and testing resistance 104；
The D.C. regulated power supply 100 and the DC reference control circuit 102 respectively symmetrically are connected to the H bridge electricity
The both ends on road 101；Wherein, the D.C. regulated power supply 100 is used to provide the direct current of constant voltage for the H-bridge circuit 101
Source；The DC reference control circuit 102 is used to be arranged the total current in the H-bridge circuit circuit；The H-bridge circuit 101 is used for
Low-impedance current loop is provided；
The H-bridge circuit 101 includes 4 electronic switches 105, and is bridged by the testing resistance 104；
The test point 103 includes voltage detecting point (test point 1 and test point 2 as shown in figure 1) and current detecting point (as schemed
Test point 3 in 1), wherein the voltage detecting point is used to detect the voltage at the testing resistance both ends, the current detecting point
For detecting the loop current of the H-bridge circuit.
Specifically, the D.C. regulated power supply 100 has stronger stability, it can be in certain output current scope
Interior, output voltage remains unchanged.
Specifically, 4 electronic switches 105 of the H-bridge circuit 101 can be metal-oxide half field effect transistor MOSFET,
MOSFET has shutdown and conducting two states, and impedance Z approaches infinitely great (impedance of 10M ohm level) when shutdown, impedance Z when conducting
Infinitely small (0.01 ohm level impedance) is approached, the consistency and symmetry of device are provided simultaneously with.Referring to FIG. 1, H-bridge circuit 101
4 MOSFET be M1, M2, M3 and M4 respectively；D.C. regulated power supply is by the circuit connection H-bridge circuit between M1 and M2, directly
Stream passes through the circuit connection H-bridge circuit between M3 and M4 with reference to control circuit.R in Fig. 1tecFor testing resistance, RtecOne end
The circuit between M1 and M3 is connected, the other end connects the circuit between M2 and M4, to realize the bridge between 4 electronic switches
It connects.When M2, M3 are connected, and M1, M4 are turned off, current loop and flow direction are as shown by solid arrows；When M1, M4 are connected, M2, M3 are turned off
When, current loop and flow direction are as the dotted line arrows；From Fig. 1, it is clear that the electric current of two current loops each other
Flow counterflow through testing resistance Rtec.There are two benefits for H-bridge circuit described in the embodiment of the present invention, one is using exchange reverse current,
Avoiding TEC temperature from changing, (characteristic of TEC is the heating of meeting producing line or refrigeration effect, temperature meeting when flowing through constant same direction current
Change)；Secondly being different flow direction can be carried out multiple repairing weld, the accuracy of data is improved.
The embodiment of the present invention is to solve the problems, such as that the measurement of prior art TEC resistance is complicated, proposes a kind of resistance
Detection circuit can carry out automatic sampling to TEC resistance and calculate, and save data, guarantee the accuracy and data of data
Trackability.It is understood that equally to can detecte resistance value larger for resistance detection circuit described in the embodiment of the present invention
Resistance.Whether larger or smaller resistance is detected, the voltage at testing resistance both ends is finally all passed through and is flowed through
Electric current, utilize Ohm's law obtain resistance value.
Resistance detection circuit described in the embodiment of the present invention is controlled by the electronic switch of H-bridge circuit, can be formed
Two opposite current loops of current direction；Contrary electricity can be applied to testing resistance respectively by two current loops
Stream, and by the voltage and loop current at test point detection testing resistance both ends, electricity to be measured can be obtained by Ohm's law
The resistance value of resistance.Provided resistance detection circuit through the embodiment of the present invention, circuit is simple, and it is biggish to can detecte resistance value
The resistance value of resistance also can detecte the resistance value of the lesser resistance of resistance value, such as the resistance of TEC, since H-bridge circuit is formed not
With the current loop of flow direction, the characteristic that testing resistance flows through constant current fever in the same direction or refrigeration is effectively avoided, it is alternately anti-
To electric current constitute complete loops and flow through testing resistance so that the temperature remains within the normal range for testing resistance, be conducive to improve computational accuracy
Based on the above embodiment, the test point 103 includes 2 voltage detecting points and 1 current detecting point, wherein institute
It states 2 voltage detecting points to be respectively arranged at two endpoints that the testing resistance 104 bridges, the current detecting point is set to
At the exit point of the DC reference control circuit 102.
Referring to FIG. 1,2 voltage detecting points of the embodiment of the present invention are respectively 2, the 1 electric current inspection of test point 1 and test point
Measuring point is test point 3.Test point 1 and test point 2 are respectively arranged at testing resistance RtecBoth ends, that is, at two endpoints bridged；
Test point 3 is arranged at the exit point of DC reference control circuit, detects the output electric current of DC reference control circuit, is H
The loop current of bridge circuit.It can be in the hope of the resistance value R of testing resistance using Ohm's law:
R=(U1-U2)/Iref；
Wherein, U1For the first voltage value, U2For second voltage value, and U1>U2, IrefFor loop current.Herein, for detection
Point 1 and the voltage value that detects of test point 2 select biggish voltage value as the first voltage value, and lesser voltage value is as the
Two voltage values, positive resistance value available in this way；If selecting lesser voltage value as the first voltage value, biggish voltage value
As second voltage value, then it is negative that resistance value, which is calculated, need to only remove absolute value at this time.
Resistance detection circuit described in the embodiment of the present invention provides three test points, utilizes Design of Amplifiers voltage
Circuit is followed, constructs each test point respectively, such test point has the characteristic of high input impedance and low output impedance, and not shadow
Ring the operation of remaining circuit.
Based on the above embodiment, the resistance detection circuit further includes reference resistance 106, the reference resistance 106
It connects with the testing resistance 104；Wherein reference resistance 104 is the resistance of high-precision fixed resistance value, and resistance value is known；
Correspondingly, the H-bridge circuit 101 is carried out by the testing resistance 104 after series connection with the reference resistance 106
Bridge joint；2 voltage detecting points are respectively arranged at the testing resistance 104 after series connection and the reference resistance 106 bridges
Two endpoints at.
Fig. 2 is a kind of resistance detection circuit structure second embodiment schematic diagram of the embodiment of the present invention, referring to FIG. 2,
When the lesser resistance of detected resistance, such as detect TEC resistance, due to TEC resistance value be ohm rank, by
What measuring resistance cascode reference resistance, test point 1 and test point 2 detected is the both ends after testing resistance cascode reference resistance respectively
Voltage value, the voltage difference that test point 1 and test point 2 can be made to detect increase, and improve the accuracy of data.Likewise,
It can be in the hope of total resistance value of reference resistance and testing resistance, since the resistance value of reference resistance will be it is known that will then ask using Ohm's law
The resistance value R of testing resistance can be obtained in the resistance value that total resistance value out subtracts reference resistance, such as following formula:
R=(U1-U2)/Iref-Rref；
Wherein, U1For the first voltage value, U2For second voltage value, and U1>U2, IrefFor loop current, RrefFor with reference to electricity
Resistance.
Based on the above embodiment, the resistance detection circuit further includes current-limiting resistance 107；The D.C. regulated power supply
The H-bridge circuit 101 is connected to after the 100 series connection current-limiting resistances 107.
Referring to FIG. 2, the R in Fig. 2limAs current-limiting resistance.The embodiment of the present invention has been connected current-limiting resistance in circuit
RlimWith reference resistance Rref, can play a protective role to TEC resistance.
Based on the above embodiment, the DC reference control circuit 102 forms constant-current source by operational amplifier and BJT,
The voltage in the input terminal of the operational amplifier is loaded by DAC control, so that DC reference control circuit output is permanent
Constant current.
Referring to FIG. 2, the stability of 102 control loop electric current of DC reference control circuit, is turned by high-precision digital-to-analogue
Parallel operation DAC exports burning voltage, controls the electric current of bipolar junction transistor BJT.The characteristic of BJT is voltage control current device, is mentioned
For constant current and the circuit of completion, establish from constant-current voltage-stabilizing source → H-bridge drive circuit → Rref+Rtec → BJT → GND
Stablize complete current loop.Wherein, in conducting, the resistance of MOSFET be can be ignored, when off, the electricity of MOSFET
Close to the Europe M rank, this characteristic can guarantee that M1, M2, M3, M4 do not interfere with the fluctuation of electric current for resistance, to guarantee the standard calculated
True property.
In conclusion resistance detection circuit described in the embodiment of the present invention by D.C. regulated power supply, H-bridge circuit, to
Measuring resistance or concatenated reference resistance and TEC resistance to be measured and DC reference control circuit form a complete electric current
Circuit.When entire circuit is completely stable, each point voltage stabilization, electric current is constant, meets Ohm's law, i.e., voltage etc. between two o'clock
In the electric current passed through multiplied by the resistance between this two o'clock.In the voltage to two test points of sampling, and samples and obtain electricity
In the case where flow valuve, so that it may the resistance between two o'clock be calculated.Circular such as previous embodiment, it is no longer superfluous herein
It states.
If Fig. 2 illustrates the situation of concatenated reference resistance 106 and TEC resistance 104 to be measured, by reference resistance RrefWith to
Test resistance RtecBe connected in series to two output ends OUTA and OUTB, while other both ends S1 and S2 being connected together, connect jointly into
DC reference control circuit, then flows into GND, forms complete current loop.
Resistance detection circuit described in the embodiment of the present invention, implementation is simple, utilizes stable electronic component, shape
At stable current loop.When carrying out resistance detection to the lesser TEC of resistance value, connected current-limiting resistance R in circuitlimWith ginseng
Examine resistance Rref, can play a protective role to TEC resistance；The current loop that different flow directions are formed by H bridge, effectively avoids
TEC flows through the characteristic of constant current fever in the same direction or refrigeration, and alternately inverted electric current constitutes complete loops and flows through TEC, makes
Obtaining TEC, the temperature remains within the normal range, is conducive to improve computational accuracy；DC reference control circuit is constructed, high-precision current constant control is obtained, is protected
Demonstrate,prove the Stability and dependability in current loop.
Fig. 3 is a kind of resistance detecting system schematic diagram of the embodiment of the present invention, resistance detection system as shown in Figure 3
System 300, including resistance detection circuit 301 described in the embodiment of the present invention and acquisition computing unit 302；
The acquisition computing unit 302 acquires testing resistance for the test point based on the resistance detection circuit
The loop current of the voltage at both ends and the resistance detection circuit, and according to the voltage at the testing resistance both ends with it is described
Loop current calculates the resistance value of the testing resistance.
It should be noted that resistance detection circuit 301 can be any embodiment institute of present invention
The resistance detection circuit stated.It acquires computing unit 302 and is calculated using the computing function of single-chip microcontroller using simple algorithm
The actual resistance of testing resistance.
A kind of resistance detection system provided in an embodiment of the present invention, including resistance detection circuit, according to resistance
The test point that resistance value detection circuit provides carries out voltage, current detecting, and is calculated according to Ohm's law, and testing resistance is obtained
Resistance value, realize process it is very simple, calculated result is accurately reliable.
Based on the above embodiment, the test point based on the resistance detection circuit acquires testing resistance both ends
Voltage and the resistance detection circuit loop current, and according to the voltage at the testing resistance both ends and the circuit
Electric current calculates the resistance value of the testing resistance, specifically includes:
The voltage detecting point of the resistance detection circuit and the number of current detecting point are acquired simultaneously by multi-channel A/D C
According to obtaining the first voltage value of described testing resistance one end, the second voltage value of the testing resistance other end and the electricity
Hinder the loop current of resistance value detection circuit；
Specifically, the data of three test points can be acquired simultaneously using high-precision multi-channel A/D C, the first voltage value is obtained
U1, second voltage value U2 and loop current Iref。
The resistance value R of the testing resistance, first formula are calculated by the first formula or the second formula are as follows:
R=(U1-U2)/Iref；
Second formula are as follows:
R=(U1-U2)/Iref-Rref；
Wherein, U1For the first voltage value, U2For second voltage value, and U1>U2, IrefFor loop current, RrefFor with reference to electricity
Resistance.
It should be noted that the first formula is used for the resistance value of testing resistance when calculating non-cascode reference resistance, such as Fig. 1 institute
Show；Second is the resistance value of testing resistance when having connected reference resistance for calculating, as shown in Figure 2.
Referring to FIG. 2, sampling obtains the voltage U1 at test point 1, the voltage U2 at test point 2 by three test points,
Electric current I at test point 3ref.Due to being the electric current and and R of the generation of DC reference control circuit at test point 3tecAnd Rref?
In same current loop, it is known that, the voltage difference between U1 and U2 is IrefWith Rref+RtecProduct (Ohm's law U=I*R).
RrefFor known precision resister, the resistance value calculated and R is subtractedrefLater, so that it may obtain RrefActual resistance value.
It should be noted that if being calculated using reversed circuit multiple repairing weld is exchanged, after being averaged, can be further improved
The accuracy of data.
Fig. 4 is a kind of resistance detection method flow diagram of the embodiment of the present invention, as shown in Figure 4 based on aforementioned reality
Apply the resistance detection method of resistance detection circuit described in example, comprising:
400, apply constant current to testing resistance by two opposite current loops of current direction respectively；
It should be noted that in step 400, the resistance detection circuit can realize through the embodiment of the present invention
Two opposite current loops of current direction can also realize that two electric currents for having current direction opposite are returned by any means
Road, the present embodiment are not especially limited this.
401, when electric current flows through the testing resistance in each current loop, the electricity at the testing resistance both ends is detected respectively
The loop current of pressure and the current loop；
Step 401 is when two opposite loop currents of current direction flow through respectively, the voltage at testing resistance both ends and circuit
Electric current.It by applying repeatedly reversed electric current, can detecte multiple as a result, each result includes the electricity at testing resistance both ends
Pressure and loop current.
402, according to the voltage at the testing resistance both ends and the loop current, obtain the measurement resistance of the testing resistance
Value.
Step 402 is the voltage and loop current at testing resistance both ends, multiple results including repeated detection；Based on each
Detection as a result, calculated using Ohm's law, obtain the resistance value of the testing resistance of each survey calculation, then it is available more
The resistance value of a survey calculation；Further according to the resistance value of multiple survey calculations, the measurement resistance value of testing resistance is obtained according to pre-defined rule.
A kind of resistance detection method provided in an embodiment of the present invention passes through two opposite current loops of current direction
Apply constant current to testing resistance, according to the loop current for the voltage and current loop for detecting testing resistance both ends, obtains
The measurement resistance value of testing resistance.The method of the embodiment of the present invention can detecte the resistance value of the biggish resistance of resistance value, can also examine
The resistance value of the lesser resistance of resistance value, such as the resistance of TEC are surveyed, due to being applied with the electricity of different flow directions on testing resistance
Stream, effectively avoids the characteristic that testing resistance flows through constant current in the same direction fever or refrigeration, alternately inverted electric current flow through to
Measuring resistance is conducive to improve computational accuracy so that the temperature remains within the normal range for testing resistance.
Based on the above embodiment, step 400, the two opposite current loops of current direction that pass through respectively are to electricity to be measured
Resistance applies constant current, specifically includes:
400.1, it is equal on described two current loops by two opposite current loops of H-bridge circuit building current direction
It is in series with testing resistance；
Specifically, Fig. 1 and Fig. 2 can be please referred to, two in step 400.1 current loop can be asked such as Fig. 1 or Fig. 2
With reference to the description of previous embodiment.
400.2, apply constant current to the H-bridge circuit by described two current loops respectively, so that the electricity
Stream flows through the testing resistance.
It should be noted that the present embodiment constitutes two current loops by H bridge, so that electric current is distinguished in the short time
Two circuits for flowing through testing resistance are established, and current direction is different, the method for this current direction reversion, which can guarantee, is testing
In time, TEC will not generate heat because electric current persistently circulates, and both ensure that the safety of device, also by multiple repairing weld
Improve the accuracy of calculating.
Based on the above embodiment, step 402, the voltage according to the testing resistance both ends and the loop current,
The measurement resistance value for obtaining the testing resistance, specifically includes:
402.1, respectively according to the voltage at the testing resistance both ends detected every time and the loop current, pass through first
Formula or the second formula calculate the resistance value R of the testing resistance, obtain multiple resistance values of the testing resistance；
402.2, the average value of the multiple resistance value is calculated, is hindered the average value as the measurement of the testing resistance
Value；
Wherein, first formula are as follows:
R=(U1-U2)/Iref；
Second formula are as follows:
R=(U1-U2)/Iref-Rref；
Wherein, U1For the first voltage value, U2For second voltage value, and U1>U2, IrefFor loop current, RrefFor with reference to electricity
Resistance.
It should be noted that the first formula is used for the resistance value of testing resistance when calculating non-cascode reference resistance, such as Fig. 1 institute
Show；Second is the resistance value of testing resistance when having connected reference resistance for calculating, as shown in Figure 2.Its calculation method and principle
As in the foregoing embodiment, details are not described herein again.
The embodiment of the present invention is passed through repeatedly detecting automatically as a result, being calculated, the testing resistance calculated every time
Resistance value；Further according to the computing the resistor value average value of testing resistance calculated every time, using average value as final measurement resistance value,
It can be further improved the accuracy of data.By practical application, TEC for resistance value in 1 Europe or so, by with large test instrument
The comparison of device, the data precision that detection of the embodiment of the present invention is calculated can reach 0.05 Europe, and error, can within 5%
Meets the needs of actual use.
Finally, it should be noted that the above embodiments are merely illustrative of the technical solutions of the present invention, rather than its limitations；Although
Present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that: it still may be used
To modify the technical solutions described in the foregoing embodiments or equivalent replacement of some of the technical features；
And these are modified or replaceed, technical solution of various embodiments of the present invention that it does not separate the essence of the corresponding technical solution spirit and
Range.
Claims (10)
1. a kind of resistance detection circuit characterized by comprising D.C. regulated power supply, H-bridge circuit, DC reference control
Circuit, test point and testing resistance；
The D.C. regulated power supply and the DC reference control circuit respectively symmetrically are connected to the both ends of the H-bridge circuit；
Wherein, the D.C. regulated power supply is used to provide the DC power supply of constant voltage for the H-bridge circuit；The DC reference control
Circuit is used to be arranged the total current in the H-bridge circuit circuit；The H-bridge circuit is for providing low-impedance current loop；
The H-bridge circuit includes 4 electronic switches, and is bridged by the testing resistance；
The test point includes voltage detecting point and current detecting point, wherein the voltage detecting point is described to be measured for detecting
The voltage at resistance both ends, the current detecting point are used to detect the loop current of the H-bridge circuit.
2. resistance detection circuit according to claim 1, which is characterized in that the test point includes 2 voltage inspections
Measuring point and 1 current detecting point, wherein 2 voltage detecting points are respectively arranged at two ends of the testing resistance bridge joint
At point, the current detecting point is set at the exit point of the DC reference control circuit.
3. resistance detection circuit according to claim 1, which is characterized in that it further include reference resistance, the reference
Resistance is connected with the testing resistance；
Correspondingly, the H-bridge circuit is bridged by the testing resistance after series connection with the reference resistance；Described 2
Voltage detecting point is respectively arranged at two endpoints of the testing resistance after series connection and reference resistance bridge joint.
4. resistance detection circuit according to claim 1-3, which is characterized in that further include current-limiting resistance；
The H-bridge circuit is connected to after the D.C. regulated power supply series connection current-limiting resistance.
5. resistance detection circuit according to claim 1, which is characterized in that the DC reference control circuit passes through
Operational amplifier and BJT form constant-current source, load the voltage in the input terminal of the operational amplifier by DAC control, so that
The DC reference control circuit exports constant current.
6. a kind of resistance detection system, which is characterized in that including the described in any item resistance detections of claim 1-5
Circuit and acquisition computing unit；
The acquisition computing unit acquires testing resistance both ends for the test point based on the resistance detection circuit
The loop current of voltage and the resistance detection circuit, and according to the voltage at the testing resistance both ends and circuit electricity
The resistance value of testing resistance described in stream calculation.
7. resistance detection system according to claim 6, which is characterized in that described to be detected based on the resistance
The test point of circuit acquires the voltage at testing resistance both ends and the loop current of the resistance detection circuit, and according to institute
The voltage and the loop current of stating testing resistance both ends calculate the resistance value of the testing resistance, specifically include:
The voltage detecting point of the resistance detection circuit and the data of current detecting point are acquired simultaneously by multi-channel A/D C, is obtained
Obtain the first voltage value, the second voltage value of the testing resistance other end and the resistance of described testing resistance one end
The loop current of detection circuit；
The resistance value R of the testing resistance, first formula are calculated by the first formula or the second formula are as follows:
R=(U1-U2)/Iref；
Second formula are as follows:
R=(U1-U2)/Iref-Rref；
Wherein, U1For the first voltage value, U2For second voltage value, and U1>U2, IrefFor loop current, RrefFor reference resistance.
8. a kind of resistance detection method based on the described in any item resistance detection circuits of claim 1-5, special
Sign is, comprising:
Apply constant current to testing resistance by two opposite current loops of current direction respectively；
When electric current flows through the testing resistance in each current loop, the voltage at the testing resistance both ends and described is detected respectively
The loop current of current loop；
According to the voltage at the testing resistance both ends and the loop current, the measurement resistance value of the testing resistance is obtained.
9. resistance detection method according to claim 8, which is characterized in that described opposite by current direction respectively
Two current loops to testing resistance apply constant current, specifically include:
Two opposite current loops of current direction are constructed by H-bridge circuit, are in series on described two current loops to be measured
Resistance；
Apply constant current to the H-bridge circuit by described two current loops respectively so that the electric current flow through it is described
Testing resistance.
10. resistance detection method according to claim 8 or claim 9, which is characterized in that described according to the testing resistance
The voltage at both ends and the loop current obtain the measurement resistance value of the testing resistance, specifically include:
Respectively according to the voltage at the testing resistance both ends detected every time and the loop current, pass through the first formula or the second formula
The resistance value R for calculating the testing resistance obtains multiple resistance values of the testing resistance；
The average value for calculating the multiple resistance value, using the average value as the measurement resistance value of the testing resistance；
Wherein, first formula are as follows:
R=(U1-U2)/Iref；
Second formula are as follows:
R=(U1-U2)/Iref-Rref；
Wherein, U1For the first voltage value, U2For second voltage value, and U1>U2, IrefFor loop current, RrefFor reference resistance.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810575551.9A CN109001536A (en) | 2018-06-05 | 2018-06-05 | A kind of resistance detection circuit, system and method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810575551.9A CN109001536A (en) | 2018-06-05 | 2018-06-05 | A kind of resistance detection circuit, system and method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109001536A true CN109001536A (en) | 2018-12-14 |
Family
ID=64599980
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810575551.9A Pending CN109001536A (en) | 2018-06-05 | 2018-06-05 | A kind of resistance detection circuit, system and method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109001536A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112816784A (en) * | 2020-12-31 | 2021-05-18 | 广电计量检测（成都）有限公司 | Resistance test circuit and system |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20050110514A1 (en) * | 2003-11-21 | 2005-05-26 | International Business Machines Corporation | Electromagnetic coupling based motor plug detect system and method |
| CN104777365A (en) * | 2014-01-10 | 2015-07-15 | 法国大陆汽车公司 | Measurement of bonding resistances |
| CN105785131A (en) * | 2016-04-21 | 2016-07-20 | 浪潮电子信息产业股份有限公司 | Testing device and method for low ohm chip resistors |
| CN205720443U (en) * | 2016-04-08 | 2016-11-23 | 镇江市越达电力设备有限公司 | A kind of reactor test device |
| CN108008191A (en) * | 2017-11-06 | 2018-05-08 | 湖北三江航天万峰科技发展有限公司 | A kind of precision aid of Minitype resistance |
-
2018
- 2018-06-05 CN CN201810575551.9A patent/CN109001536A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20050110514A1 (en) * | 2003-11-21 | 2005-05-26 | International Business Machines Corporation | Electromagnetic coupling based motor plug detect system and method |
| CN104777365A (en) * | 2014-01-10 | 2015-07-15 | 法国大陆汽车公司 | Measurement of bonding resistances |
| CN205720443U (en) * | 2016-04-08 | 2016-11-23 | 镇江市越达电力设备有限公司 | A kind of reactor test device |
| CN105785131A (en) * | 2016-04-21 | 2016-07-20 | 浪潮电子信息产业股份有限公司 | Testing device and method for low ohm chip resistors |
| CN108008191A (en) * | 2017-11-06 | 2018-05-08 | 湖北三江航天万峰科技发展有限公司 | A kind of precision aid of Minitype resistance |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112816784A (en) * | 2020-12-31 | 2021-05-18 | 广电计量检测（成都）有限公司 | Resistance test circuit and system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107345996A (en) | FET test circuit and method of testing | |
| CN102495650A (en) | Multi-stage refined precise temperature control device and control method | |
| TW201344210A (en) | Grounded impedance testing apparatus and probe having same | |
| CN204347229U (en) | The calibrating installation of active leakage current tester | |
| CN109001536A (en) | A kind of resistance detection circuit, system and method | |
| TWI394939B (en) | Temperature measure system and method | |
| EP3918352B1 (en) | Electricity meter | |
| CN106526286B (en) | Current detection circuit, method and battery system | |
| CN204102398U (en) | For the experimental box of the volt-ampere characteristic and resistance-temperature characteristic of studying thermistor | |
| US3845388A (en) | Rms converter | |
| US20200049744A1 (en) | Apparatus and method for determining a power value of a target | |
| RU2707757C1 (en) | Method of reducing measurement error of temperature with electric bridge | |
| RU96430U1 (en) | DEVICE FOR EXPRESS DIAGNOSTICS OF IDENTITY OF TRANSISTORS | |
| CN205845269U (en) | Transformator running temperature pressure out-of-limit alarming device | |
| CN213067984U (en) | Constant current circuit for temperature measurement and circuit breaker mechanical characteristic monitoring device | |
| CN105067886B (en) | A kind of method and apparatus for measuring resistance load coefficient | |
| CN110672187B (en) | Sensor symmetry detection method and device | |
| CN215865540U (en) | Thermocouple cold junction compensation circuit and thermocouple temperature measurement system | |
| US20220413017A1 (en) | Measuring method for determining the current through a shunt resistor | |
| CN111504486A (en) | Constant current circuit for temperature measurement and circuit breaker mechanical characteristic monitoring device | |
| RU2664880C1 (en) | Compensating type tracking current converter | |
| JP6132718B2 (en) | Impedance measuring apparatus and impedance measuring method | |
| SU780085A1 (en) | Device for measuring asymmetry of thermoelements of bridge-type | |
| JPS60169181A (en) | Temperature controlling system for semiconductor laser | |
| JPH11304877A (en) | Voltage applying current measuring circuit |
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 | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20181214 |