CN108534819A - A kind of constant current or constant pressure sensor analog system and method - Google Patents
A kind of constant current or constant pressure sensor analog system and method Download PDFInfo
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- CN108534819A CN108534819A CN201810562926.8A CN201810562926A CN108534819A CN 108534819 A CN108534819 A CN 108534819A CN 201810562926 A CN201810562926 A CN 201810562926A CN 108534819 A CN108534819 A CN 108534819A
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- 238000012360 testing method Methods 0.000 claims abstract description 38
- 238000004088 simulation Methods 0.000 claims abstract description 19
- 239000003990 capacitor Substances 0.000 claims description 10
- 230000005611 electricity Effects 0.000 claims description 4
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
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Abstract
The invention discloses a kind of constant current or constant pressure sensor analog system and methods, including signal generating unit, the output end of signal generating unit is connected with signal imitation unit, signal imitation unit for realizing sensor signal simulation, the output end of signal imitation unit is connected with signal buffer smooth unit, signal buffer smooth unit is for adjusting the sensor signal that signal imitation unit is sent out, in order to which the sample circuit of the signal and Devices to test matches, and the sensor signal adjusted is sent to Devices to test；The present invention abandoned it is traditional utilize physical sensor, build local test environment in laboratory environments, come verify equipment under test ability to work method.It is easily programmed using one-chip computer chip, smooth and load capacity raising of the digital regulation resistance convenient for control and integral buffer circuit to output signal, ingenious cooperation, Sensor Analog Relay System circuit is constituted, the sensor signal under true, effective various environmental conditions is provided for equipment under test.
Description
【Technical field】
The invention belongs to electronic measuring technology field more particularly to a kind of constant current or constant pressure sensor analog system and sides
Method.
【Background technology】
In electronic surveying field, it is often necessary in laboratory environments, be simulated to various kinds of sensors, be equipment under test
All kinds of analog signals are provided, the ability worked normally under all kinds of operating modes is devices under with verification.
Common analogy method is in laboratory environments, using the sensor similar with equipment under test, to build part examination
Environment is tested, to verify the ability to work of equipment under test, equivalent block diagram is as shown in Figure 1, still, this method is clearly present following
Problem：
1, it needs to build working sensor environment in laboratory：The working environment of sensor may be very extreme, such as：High/
Low temperature, high pressure, vacuum, high speed etc..
2, it is not suitable for the fierce variation of environmental condition：Simulation test environment needs the regular hour, when user needs soon
When fast simulated environment variation, the structure of experimental enviroment can relative difficulty.
3, some sensors are unsuitable for simulating in laboratory environments：Some sensors, due to volume, mounting means, guarantor
Close needs or other reasons, are unsuitable for being simulated in laboratory environments, cause equipment under test discrete function that can not test
It is tested under room environmental.
【Invention content】
The object of the present invention is to provide a kind of constant current or constant pressure sensor analog system and methods, do not need additional experiment
Environment can analog sensor response signal.
The present invention uses following technical scheme：A kind of constant current or constant pressure sensor analog system, including signal generating unit,
The output end of signal generating unit is connected with signal imitation unit, signal imitation unit for realizing sensor signal simulation,
The output end of signal imitation unit is connected with signal buffer smooth unit, and signal buffer smooth unit is quasi-simple for adjusting signal mode
The sensor signal that member is sent out, the sensor that matches in order to the sample circuit of the signal and Devices to test, and will adjust
Signal is sent to Devices to test；
Signal imitation unit includes digital regulation resistance, the bus interface of digital regulation resistance and the output end of signal generating unit
It is connected, and its output end is connected with the signal input part of signal buffer smooth unit；
Resistance R1 and resistance R2, the other end ground connection of resistance R2, electricity is also respectively connected in the terminal up and down of digital regulation resistance
The other end for hindering R1 is connect with the anode in constant current/constant voltage source, the cathode ground connection in constant current/constant voltage source；
When resistance R1 is connected with constant-current source, the upper terminal of digital regulation resistance and its output end short circuit, digital regulation resistance
Output end be connected to the signal input part of signal buffer smooth unit.
Further, signal buffer smooth unit includes integral buffer amplifier U1 and integrating capacitor C1 in parallel, integral
The negative input of buffer amplifier U1 and one end of integrating capacitor C1 are connect with the output end of digital regulation resistance, integral buffering
The positive input of amplifier U1 is grounded；The other end of integrating capacitor C1 is connected simultaneously with the output end of integral buffer amplifier U1
Analog signal is sent to Devices to test.
Further, the voltage range of sensor analog system output signal is V1~V2, wherein V1For output wire size
Upper voltage limit, and V1=Im* R1, V2For the lower voltage limit of output signal, and V2=Im* R2, ImFor the output electricity in constant current/constant voltage source
Stream.
The another technical solution of the present invention：A kind of constant current or constant pressure sensor simulation method, use a kind of above-mentioned perseverance
Stream or constant pressure sensor analog system, specifically include following steps：
Step 1, the desired signal according to Devices to test, the input parameter of setting signal generator select constant current/constant voltage
Source, resistance R1 and resistance R2；
Step 2, signal generator generate burst signal according to input parameter, and the bus for being sent to digital regulation resistance connects
Mouthful；
Step 3, digital regulation resistance generate the mould of simultaneously output transducer according to the input signal of bus interface and upper and lower terminal
Quasi- signal, and it is sent to signal buffer smooth unit；
Step 4 is smoothed and is filtered out to the analog signal of the sensor of reception by signal buffer smooth unit
Interference, and it is sent to Devices to test.
The beneficial effects of the invention are as follows：The present invention has abandoned traditional utilization physical sensor, in laboratory environments structure
Found the bureau portion's experimental enviroment, come verify equipment under test ability to work method.It is easily programmed using one-chip computer chip, number
Convenient for controlling and integrating smooth and load capacity raising of the buffer circuit to output signal, ingenious cooperation is constituted and is passed potentiometer
Sensor analog circuit provides the sensor signal under true, effective various environmental conditions, with traditional utilization for equipment under test
Physical sensor, structure local test environment is compared come the method for verifying the ability to work of equipment under test in laboratory environments,
Output signal setting of the present invention is simple, clear and free from the influence of the external environment, and a kind of unit simulation multiple sensors also can be used
The case where output signal, the parameter that the present invention passes through change signal generator, so that it may which Fast simulation actual sensor is in different rings
Output signal under the conditions of border effectively promotes testing efficiency, and simulation type is wide, and the output signal of analog sensor is either straight
It flows signal, can also be alternating signal, modulated signal.
【Description of the drawings】
Fig. 1 is the functional block diagram of existing verification equipment under test；
Fig. 2 is the schematic block circuit diagram when present invention uses constant-current source；
Fig. 3 is the schematic block circuit diagram when present invention uses constant pressure source；
Fig. 4 is a kind of practical application brief principle figure of the present invention.
【Specific implementation mode】
The following describes the present invention in detail with reference to the accompanying drawings and specific embodiments.
The invention discloses a kind of constant current or constant pressure sensor analog systems, shown in Fig. 3, including signal generating unit, one
As selection signal generator as signal generating unit, can be made of general singlechip chip and its peripheral components, in list
It is the burst signal of one group of control digital regulation resistance change in resistance with corresponding firmware, output in piece movement piece, and waits for
Analog sensor signal variation is corresponding.Signal generator has programmable interface, facilitates according to the difference for waiting for analog sensor, compiles
It different signal waveforms is made, can also input different parameters by programmable interface, analog sensor is under various circumstances
Output signal.
Using microcontroller as signal source in designing circuit, can be provided according to sensor production producer in a piece of chip
Output parameter, different waveforms, frequency, phase, amplitude be set, realizes that set of device can simulate multiple sensors in difference
Output under environment.
The output end of signal generating unit is connected with signal imitation unit, and signal imitation unit is for realizing sensor signal
Simulation, signal imitation unit includes digital regulation resistance, the bus interface of digital regulation resistance and the output end of signal generating unit
It is connected, and its output end is connected with the signal input part of signal buffer smooth unit.
Resistance R1 and resistance R2, the other end ground connection of resistance R2, electricity is also respectively connected in the terminal up and down of digital regulation resistance
The other end for hindering R1 is connect with the anode in constant current/constant voltage source, the cathode ground connection in constant current/constant voltage source.As shown in Fig. 2, working as resistance R1
When being connected with constant-current source, the upper terminal of digital regulation resistance and its output end short circuit, the output end of digital regulation resistance are connected to letter
The signal input part of number buffering and smoothing unit.
Signal generator exports the pulse of one group of control digital regulation resistance change in resistance according to the demand for waiting for analog sensor
String signal changes the resistance value of digital regulation resistance, makes the voltage respective change on digital regulation resistance, realizes digital circuit analog sensed
The target of device output signal.
In the digital regulation resistance using constant-current source, digital regulation resistance is connected by the form of variable resistance, then output signal
For Vs=(Ws+R2) Im, wherein Ws is the resistance value for the variable resistance that digital regulation resistance is constituted, ImFor the defeated of constant-current source or constant pressure source
Go out electric current.R1 and R2 is to offset the intrinsic Dead Zone of actual sensor, it is ensured that Vs signals and actual sensor output are special
Property is consistent.The digit of digital regulation resistance can consider by the required precision of analog sensor is waited for.Since actual sensor can not all be kept away
That exempts from carries dead zone, for true, effective analog sensor signal, should be joined according to the sensor that sensor production producer provides
The resistance value of R1, R2 is arranged in number.The voltage range of sensor analog system output signal is V1~V2, wherein V1To export wire size
Upper voltage limit, and V1=Im* R1, V2For the lower voltage limit of output signal, and V2=Im*R2。
Often internal resistance is higher for the signal source that digital regulation resistance is formed, and is not easy to match with test circuit, so, signal imitation
The output end of unit is connected with signal buffer smooth unit, and signal buffer smooth unit is for adjusting what signal imitation unit was sent out
Sensor signal in order to which the sample circuit of the signal and Devices to test matches, and the sensor signal adjusted is sent
To Devices to test.
Using digital regulation resistance can easily by its resistance value of Digital Circuit Control the characteristics of, realize the mould of sensor signal
It is quasi-.
The signal of digital regulation resistance output is step-like, for real simulation sensor output signal, using signal buffer
Smooth unit carries out it smoothly, and signal buffer smooth unit includes the integral buffer amplifier U1 and integrating capacitor C1 of parallel connection,
Integral buffer amplifier U1 can be smoothed analog signal, and integrating capacitor C1 is used to filter out the various dry of analog signal
It disturbs.The negative input of integral buffer amplifier U1 and one end of integrating capacitor C1 are connect with the output end of digital regulation resistance,
Integrate the positive input ground connection of buffer amplifier U1；The output end of the other end of integrating capacitor C1 and integral buffer amplifier U1
It is connected, and analog signal that is smooth and filtering out after interference is sent to Devices to test.
Integral buffer amplifier U1 is matching and the smooth number potentiometer in order to facilitate simulation signal generator and test circuit
The step of output signal, digital regulation resistance output impedance is higher, is not easy to coordinate with the sample circuit of test equipment, therefore uses slow
Device circuit is rushed, the load capacity of VOUT is improved, keeps the output signal of output VOUT signals and actual sensor consistent.
The invention also discloses a kind of constant current or constant pressure sensor simulation method, passed using a kind of above-mentioned constant current or constant pressure
Sensor simulation system is suitable for all kinds of constant current/constant voltages under simulated experiment room environmental and drives sensor, specifically includes following steps：
Step 1, the desired signal according to Devices to test send out the output parameter for the sensor for waiting for analog signal, setting
The input parameter of signal generator, and constant current or constant pressure source are selected, the resistance value of resistance R1 and the resistance value of resistance R2.
Step 2, signal generator generate burst signal according to input parameter, and the bus for being sent to digital regulation resistance connects
Mouthful.
Step 3, digital regulation resistance generate the mould of simultaneously output transducer according to the input signal of bus interface and upper and lower terminal
Quasi- signal, and it is sent to signal buffer smooth unit.
Step 4 is smoothed and is filtered out to the analog signal of the sensor of reception by signal buffer smooth unit
The interference generated in circuit, and analog signal is sent to Devices to test by treated.
The present invention does not need true sensor, does not need additional experiment bad border yet, so that it may provide biography to equipment under test
Therefore sensor analog signal is not influenced by environmental change, and can simulate the corresponding signal of various kinds of sensors, to equipment under test
It is completely tested, improves the feasibility of test system.
As shown in figure 4, for a kind of practical application brief principle figure of the embodiment of the present invention, by design requirement, simulation is a kind of
Speed sensor signal.It is driven using 1mA constant-current sources, constant-current source open-circuit voltage is 15V, and it is symmetrical that output signal, which is with 7.5V,
The peak-to-peak value of axis is the sine wave of 10V, centre frequency 1KHz.
U1 is a general microcontroller, can be previously written required waveform signal in its memory by JZ1 interfaces,
In chip operational process, user can be changed its waveform parameter in host computer by JZ2 interfaces, different to simulate
Speed.U1 passes through I2C buses, the running point position for controlling digital regulation resistance are changed by waveform rule, form required waveform, due to
Digital regulation resistance output is staircase waveform, therefore is filtered to output waveform using integrator in output end, obtains being equivalent to true speed
Spend the waveform of sensor output.
Since maximum changing range is 10V, therefore digital regulation resistance selects 10K resistance values；Since constant-current source open-circuit voltage is
15V, waveform symmetry axis are therefore 7.5V, wave-shape amplitude 10V calculate R1：Similarly, may be used
Calculate R2=2.5K Ω
Since digital regulation resistance absolute error is larger, relative error is smaller, therefore, is desirable to carefully tune in practical application
The resistance value of R1, R2 meets design condition.
Claims (4)
1. a kind of constant current or constant pressure sensor analog system, which is characterized in that including signal generating unit, the signal occurs single
The output end of member is connected with signal imitation unit, and the signal imitation unit is for realizing the simulation of sensor signal, the letter
The output end of number analogue unit is connected with signal buffer smooth unit, and the signal buffer smooth unit is for adjusting the signal
The sensor signal that analogue unit is sent out in order to the sample circuit of the signal and Devices to test matches, and will be adjusted
Sensor signal is sent to Devices to test；
The signal imitation unit includes digital regulation resistance, the bus interface of the digital regulation resistance and signal generating unit it is defeated
Outlet is connected, and its output end is connected with the signal input part of signal buffer smooth unit；
Resistance R1 and resistance R2, another termination of the resistance R2 is also respectively connected in the terminal up and down of the digital regulation resistance
Ground, the other end of the resistance R1 are connect with the anode in constant current/constant voltage source, the cathode ground connection in the constant current/constant voltage source；
When the resistance R1 is connected with constant-current source, the upper terminal of the digital regulation resistance and its output end short circuit, the number
The output end of word potentiometer is connected to the signal input part of the signal buffer smooth unit.
2. a kind of constant current as described in claim 1 or constant pressure sensor analog system, which is characterized in that the signal buffer is flat
Sliding unit includes the integral buffer amplifier U1 and integrating capacitor C1 of parallel connection, the negative input of the integral buffer amplifier U1
It is connect with the output end of the digital regulation resistance with one end of integrating capacitor C1, the forward direction of the integral buffer amplifier U1 is defeated
Enter end ground connection；The other end of the integrating capacitor C1 is connected with the output end of the integral buffer amplifier U1 and believes simulation
Number it is sent to Devices to test.
3. a kind of constant current as claimed in claim 1 or 2 or constant pressure sensor analog system, which is characterized in that the sensor
The voltage range of simulation system output signal is V1~V2, wherein V1To export the upper voltage limit of wire size, and V1=Im* R1, V2For
The lower voltage limit of output signal, and V2=Im* R2, ImFor the output current in constant current/constant voltage source.
4. a kind of constant current or constant pressure sensor simulation method, passed using a kind of any described constant currents of claim 1-3 or constant pressure
Sensor simulation system, which is characterized in that specifically include following steps：
Step 1, the desired signal according to Devices to test, the input parameter of setting signal generator select constant current/constant voltage source, electricity
Hinder R1 and resistance R2；
Step 2, signal generator generate burst signal according to input parameter, and are sent to the bus interface of digital regulation resistance；
Step 3, digital regulation resistance generate according to the input signal of bus interface and upper and lower terminal and the simulation of output transducer are believed
Number, and it is sent to signal buffer smooth unit；
Step 4 is smoothed and is filtered out to the analog signal of the sensor of reception by the signal buffer smooth unit
Interference, and it is sent to Devices to test.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114115167A (en) * | 2020-08-27 | 2022-03-01 | 郑州深澜动力科技有限公司 | Battery pack fire extinguishing test system |
| CN114335760A (en) * | 2020-09-25 | 2022-04-12 | 郑州深澜动力科技有限公司 | Battery pack fire extinguishing function test system |
| WO2022088403A1 (en) * | 2020-10-27 | 2022-05-05 | 合肥科威尔电源系统股份有限公司 | Low-current wide-range adjustable pulse constant current source circuit |
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