CN202049354U - Virtual measurement and control system - Google Patents
Virtual measurement and control system Download PDFInfo
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- CN202049354U CN202049354U CN2011200303843U CN201120030384U CN202049354U CN 202049354 U CN202049354 U CN 202049354U CN 2011200303843 U CN2011200303843 U CN 2011200303843U CN 201120030384 U CN201120030384 U CN 201120030384U CN 202049354 U CN202049354 U CN 202049354U
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Abstract
The utility model relates to a virtual measurement and control system and aims to provide a practical virtual measurement and control system provided with a low-cost signal acquisition module, which comprises an interface circuit and a virtual simulation device, wherein the virtual simulation device is connected with a measured control system through the interface circuit, and the interface circuit comprises a processor, an analog-to-digital conversion circuit, a duty ratio measurement circuit, an input amplification regulating circuit, a T-shaped conversion circuit, a 24-bit AD conversion circuit, an output amplification regulating circuit, a digital-to-analog conversion circuit, a switching value conversion circuit, a communication interface and a terminal. The utility model provides a system utilizing a virtual device for system debugging, an expensive controlled device is not needed, the debugging process is simple and feasible, and the development efficiency of products is improved; and PWA signals, analog signals and switching value signals can be processed in a signal acquisition circuit, I/O (Input/Output) interfaces of the processor are reduced, the virtual measurement and control system has a simple structure, and the cost of equipment is reduced.
Description
Technical field
The utility model relates to the computer virtual field tests, and in particular, the utility model is a kind of virtual measuring and controling system about control system virtual detection and control.
Background technology
Observing and controlling electronic product exploitation general flow: conceptual design → hardware design → software design → system debug → technological document is write.Wherein system debug is one of key link of observing and controlling product development.Usually need object in kind to debug in debug process, exploitation as controller for electric vehicle, need the place, battery etc. of electric motor car, electric motor car operation just can debug, the temperature Control of Electric Heater system needs electric furnace, AC power etc. just can debug, owing to when debugging, influenced by the service condition of equipment, debug process is very loaded down with trivial details, and causes damage easily to some equipment debugging is improper.
Patent Office of the People's Republic of China discloses a CN101749302A document on June 23rd, 2010, name is called a kind of hydraulically operated equipment (HOE) on-line virtual testing analysis system, this system utilizes computer platform to set up, it comprises: acquisition module, and it utilizes PXIe acquisition platform, SCXI Platform for Signal Condition and CDAQ portable data acquisition platform image data; Administration module, it comprises a data ADMINISTRATION SUBSYSTEM; Reporting modules, it will show in word form mode at the test findings that object is done; Analysis module, it comprise one with data test partly adopt the waveform result carry out the eigenwert collection, the analyzing subsystem that the result of needs is extracted.The shortcoming of this system is that signal acquisition module is made of complex structure, cost height PXIe acquisition platform, SCXI Platform for Signal Condition and CDAQ portable data acquisition platform.
Summary of the invention
The utility model provides a kind of virtual measuring and controling system with practicality of low-cost signal acquisition module for solving the high shortcoming of the complicated cost of signal acquisition structure that exists in the prior art.
The technical scheme that its technical matters that solves the utility model adopts is: the utility model comprises interface circuit and virtual emulation equipment, virtual emulation equipment links to each other with tested control system by interface circuit, interface circuit comprises processor, analog to digital conversion circuit, the duty ratio measuring circuit, the adjustment circuit is amplified in input, T type change-over circuit, 24 A/D convertor circuits, the adjustment circuit is amplified in output, D/A converting circuit, the switching value change-over circuit, communication interface and terminal, the signal output part of tested control system by terminal respectively with the duty ratio measuring circuit, the adjustment circuit is amplified in input, the input end of T type change-over circuit links to each other, the duty ratio measuring circuit, input is amplified the output terminal of adjusting circuit and is linked to each other with the input end of analog to digital conversion circuit, the output terminal of analog to digital conversion circuit links to each other with the input end of processor, the output terminal of T type change-over circuit links to each other with the input end of 24 A/D convertor circuits, the output terminal of 24 A/D convertor circuits links to each other with the input end of processor, the output terminal of processor respectively with D/A converting circuit, the input end of switching value change-over circuit links to each other, the output terminal of D/A converting circuit amplifies the input end of adjusting circuit with output and links to each other, and the output terminal of circuit is adjusted in the output amplification and the output terminal of switching value change-over circuit links to each other with the input end of tested control system by terminal respectively; Processor links to each other with virtual emulation equipment by communication interface; Emulator comprises PC.
The duty ratio measuring circuit is used for the analog quantity voltage signal of conversion of signals for become related function to concern with the dutycycle of pwm signal with the PWM type of tested control system output, this analog quantity voltage signal is handled through the analog to digital conversion circuit sending processor, and delivers to PC by communication interface virtual objects is controlled;
Input is amplified the adjustment circuit and is used for converting the voltage or the current analog signal of tested control system output to the analog quantity voltage signal, this analog quantity voltage signal is handled through the analog to digital conversion circuit sending processor, and delivers to PC by communication interface virtual objects is controlled;
The multi-way switch amount conversion of signals that T type change-over circuit is used for tested control system output is a simulating signal, be converted to digital signal through 24 A/D convertor circuits, this digital signal sending processor is handled, and delivers to PC by communication interface virtual objects is controlled;
The data-signal of virtual objects output is by the communication interface of interface processor, and treated device is delivered to D/A converting circuit and delivered to output amplification adjustment circuit output simulating signal to tested control system, and this signal also can be used as the virtual sensing signal of virtual objects;
The digital signal of virtual objects output is by communication interface, and the I/O mouth of treated device is isolated output, changes through output conversion circuit, delivers to the on off state output of tested control system as virtual unit.Signal between tested control system and the processor is divided into pwm signal, simulating signal and switching value signal, the pwm signal of tested control system output is converted into and the proportional simulating signal of pwm signal dutycycle through the duty ratio measuring circuit, simulating signal is handled through the analog to digital conversion sending processor, and controls by the virtual objects that communication interface is delivered to PC; The simulating signal of tested control system output links through level conversion and analog to digital conversion circuit and processor, the multi-way switch amount control signal of tested control system output becomes simulating signal through T type change-over circuit, send the conversion of 24 bit A/D converters, and deliver to the virtual objects of PC by communication interface; The communication interface of interface circuit inside and the virtual unit exchange message on the PC, virtual unit moves or provides corresponding signal to tested control system according to the signal of tested control system.
As preferably, the duty ratio measuring circuit comprises the voltage-controlled low pass active filter circuit of holding circuit, current rectifying and wave filtering circuit and single supply; Holding circuit is made up of diode D1; current rectifying and wave filtering circuit is made up of diode D2, capacitor C 1, resistance R 1; the PWM input signal; send diode D2, capacitor C 1 and resistance R 1 to carry out rectifying and wave-filtering through the D1 pressure limiting, export the direct current signal of 0-5V then by the voltage-controlled low pass active filter circuit of the single supply of forming by resistance R 2, R3, R4, R5, capacitor C 2, C3 and operational amplifier A 1.The duty ratio measuring circuit is made of the voltage-controlled low pass active filter circuit of holding circuit, current rectifying and wave filtering circuit and single supply; The PWM input signal of 1-30V send diode D, capacitor C 1 to carry out rectifying and wave-filtering through the D1 pressure limiting, and the voltage-controlled low pass active filter circuit of forming by R2, R3, R4, R5, C2, C3 and operational amplifier A 1 of single supply is exported the direct current signal of 0-5V then.
As preferably, import amplification adjustment circuit 0-24V voltage signal and 0-20mA current signal are converted to the 0-5V voltage signal.Input amplify to be adjusted circuit and is had automatic gain and adjust function, the simulating signal that voltage signal and the 0-20mA current signal of 0-24V is converted to 0-5V.
As preferably, T type change-over circuit comprises several T type circuit, operational amplifier A 30, resistance R 30 and diode D21, T type circuit comprises resistance R 20, R21, R22, diode D20, triode Q20, and wherein the resistance of the described resistance R 20 of the resistance value ratio of resistance R 21 is twice; One end of resistance R 20 links to each other with an end of resistance R 21, the other end of resistance R 21 links to each other with the positive pole of diode D20, the collector of triode Q20 respectively, the emitter of triode Q20 links to each other with ground, and the base stage of triode Q20 links to each other with tested control system as signal input part by resistance R 22; When T type circuit connects, the other end of the resistance R 20 of the described T type of first via circuit links to each other with positive source, resistance R 20 in the other end of the resistance R 20 of each road T type circuit of back and front one road T type circuit and the tie point of R21 are connected, and the resistance R 20 of last road T type circuit links to each other with ground by diode D21; The negative pole of the diode D20 of each road T type circuit links together and links to each other with the input cathode of described operational amplifier A 30, the input anode of operational amplifier A 30 links to each other with ground, one end of resistance R 30 links to each other with the input cathode of operational amplifier A 30, and the other end of resistance R 30 links to each other with the output terminal of operational amplifier A 30.The switching value signal of tested control system links to each other with the base stage of the triode Q20 of one road T type circuit by resistance R 22 respectively, controls the break-make of the triode Q1 on this road respectively; When the signal input part in the T on a certain road type circuit is high level, the triode Q20 conducting of this road, diode D20 is static, and this road T type circuit does not have signal output; When the signal input part of this T type circuit was low level, triode Q2O ended, and the diode D2O conducting of this road is sent to output terminal with the magnitude of voltage on the triode Q20 collector of this road; Because the voltage when each road T type circuit ends at this road triode Q20 on its collector is different, therefore the voltage added value to output terminal also has nothing in common with each other, because, the resistance of the resistance value ratio resistance R 20 of resistance R 21 is twice, so the output voltage of each road T type circuit launches the added value weight by a certain percentage of output end voltage; The diode D20 on each road guarantees the unidirectional conducting of signal, and diode D21 plays equilibrium activity; Operational amplifier A 30 is amplified the output signal of each road T type circuit; The advantage of T type change-over circuit is can reduce tested control system to the signal delay between virtual unit; Can guarantee the synchronous output of each switching value signal, the control virtual objects; Thereby the detection that can cascade expands to 24 path switching signals reduces the I/O mouth quantity of processor.
As preferably, 24 A/D convertor circuits are LTC2400 chips.The LTC2400 chip adopts delta sigma structure, three-wire system SPI interface, has that volume is little, slewing rate is fast, the simple advantage of wiring.
As preferably, communication interface comprises the RS232 serial ports.The RS232 serial ports has easy-to-connect, the advantage that communication speed is fast.
As preferably, communication interface comprises USB interface.USB interface has plug and play advantage easy to use.
The beneficial effects of the utility model are: a kind of system that adopts virtual unit to carry out system debug is provided, has not needed expensive controlled device, made debug process simple, improved the efficient of product development; In the teaching of university's electrical type specialty, adopt virtual unit to debug, have bigger advantage, can reduce the input of experimental facilities, reduce the management and the maintenance cost of equipment; In signal acquisition circuit, can handle, and reduce the I/O interface of processor pwm signal, analog signals, switching value signal, simple in structure, reduced equipment cost.
Description of drawings
Fig. 1 is a kind of system chart of the utility model virtual measuring and controling system;
Fig. 2 is a kind of block diagram of interface circuit;
Fig. 3 is a kind of schematic diagram of duty ratio measuring circuit;
Fig. 4 is a kind of schematic diagram of T type circuit;
Fig. 5 is a kind of schematic diagram of T type change-over circuit.
Among the figure: 1. virtual measuring and controling system, 2. interface circuit, 3. virtual emulation equipment, 4. tested control system, 5. processor, 6. terminal, 7. duty ratio measuring circuit, 8. analog to digital conversion circuit, 9. input is amplified and is adjusted circuit, 10.T type change-over circuit, 11.24 amplifying, position A/D convertor circuit, 12. outputs adjust circuit, 13. D/A converting circuits, 14. the switching value change-over circuit, 15. communication interfaces.
Embodiment
Below by specific embodiment, and in conjunction with the accompanying drawings the technical solution of the utility model is described in further detail.
Embodiment:
A kind of virtual measuring and controling system of present embodiment, referring to Fig. 1, form virtual measuring and controling system 1 by interface circuit 2 and virtual emulation equipment 3, one end of interface circuit 2 links to each other with tested control system 4, the other end of interface circuit 2 links to each other with virtual emulation equipment 3, and virtual emulation equipment 3 comprises PC computer and 3D virtual software.
Referring to Fig. 2, interface circuit 2 comprises processor 5, analog to digital conversion circuit 8, duty ratio measuring circuit 7, input amplification adjustment circuit 9,10,24 A/D convertor circuits 11 of T type change-over circuit, exports to amplify and adjust circuit 12, D/A converting circuit 13, switching value change-over circuit 14, communication interface 15 and terminal 6; The signal output part of tested control system 4 by terminal 6 respectively with duty ratio measuring circuit 7, adjustment circuit 9 is amplified in input, the input end of T type change-over circuit 10 links to each other, duty ratio measuring circuit 7, input is amplified the output terminal of adjusting circuit 9 and is linked to each other with the input end of analog to digital conversion circuit 8, the output terminal of analog to digital conversion circuit 8 links to each other with the input end of processor 5, the output terminal of T type change-over circuit 10 links to each other with the input end of 24 A/D convertor circuits 11, the output terminal of 24 A/D convertor circuits 11 links to each other with the input end of processor 5, the output terminal of processor 5 respectively with D/A converting circuit 13, the input end of switching value change-over circuit 14 links to each other, the output terminal of D/A converting circuit 13 amplifies the input end of adjusting circuit 12 with output and links to each other, and the output terminal of circuit 12 is adjusted in the output amplification and the output terminal of switching value change-over circuit 14 links to each other with the input end of tested control system 4 by terminal 6 respectively; Processor 5 links to each other with virtual emulation equipment 3 by communication interface 15.
Referring to Fig. 3, duty ratio measuring circuit 7 comprises the voltage-controlled low pass active filter circuit of holding circuit, current rectifying and wave filtering circuit and single supply; Holding circuit is made up of diode D1, and current rectifying and wave filtering circuit is made up of diode D2, capacitor C 1, resistance R 1, and the voltage-controlled low pass active filter circuit of single supply is made up of resistance R 2, R3, R4, R5, capacitor C 2, C3 and operational amplifier A 1.
Referring to Fig. 4, T type circuit comprises resistance R 20, R21, R22, diode D20, triode Q20, and wherein the resistance of the described resistance R 20 of the resistance value ratio of resistance R 21 is twice; One end of resistance R 20 links to each other with an end of resistance R 21, the other end of resistance R 21 links to each other with the positive pole of diode D20, the collector of triode Q20 respectively, the emitter of triode Q20 links to each other with ground, and the base stage of triode Q20 links to each other with tested control system 4 as signal input part by described resistance R 22.
Referring to Fig. 5, T type change-over circuit 10 is made up of 16 road T type circuit, operational amplifier A 30, resistance R 30 and diode D21, one end of the resistance R 20 of first via T type circuit links to each other with positive source, resistance R 20 in one end of the resistance R 20 of each road T type circuit of back and front one road T type circuit and the tie point of R21 are connected, and the resistance R 20 of last road T type circuit links to each other with ground by diode D21; The negative pole of the diode D20 of each road T type circuit links together and links to each other with the input cathode of described operational amplifier A 30, the input anode of operational amplifier A 30 links to each other with ground, one end of resistance R 30 links to each other with the input cathode of operational amplifier A 30, and the other end of resistance R 30 links to each other with the output terminal of operational amplifier A 30.
24 A/D convertor circuits 11 are made up of the LTC2400 chip.
Signal between tested control system 4 and the interface circuit 2 is divided into pwm signal, analog signals and switching value signal, pwm signal is converted to and the proportional simulating signal of pwm signal dutycycle by duty ratio measuring circuit 7, be converted to digital signal through analog to digital conversion circuit 8 again, be sent to processor 5 and handle; The analog signals of tested control system 4 amplifies adjustment circuit 9 by input and carries out the level adjustment, 0-24V voltage signal and 0-20mA current signal are converted to the 0-5V voltage signal, be converted to digital signal through analog to digital conversion circuit 8 again, be sent to processor 5 and handle; The switching value signal of tested control system 4 is converted to by the voltage signal of weighing addition through T type change-over circuit 10, is converted to digital quantity signal by 24 A/D convertor circuits 11 again, is sent to processor 5 and handles.
The signal that interface circuit 2 outputs to tested control system 4 is divided into analog signals and switching value signal, analog signals is converted to the voltage analog signal of 0-5V through D/A converting circuit 13 by the digital quantity signal of processor 5 outputs, amplify adjustment circuit 12 by output again and carry out the level adjustment, be converted to 0-24V voltage signal and 0-20mA current signal, as the control signal or the feedback signal of tested control system 4; The switching value signal of processor 5 outputs is active signals of 5V, is converted to passive switch amount signal by switching value change-over circuit 14, is transported to control signal and the status signal of tested control system 4 as virtual emulation equipment 3.
PC exchange message in the communication interface 15 of interface circuit 2 inside and the virtual emulation equipment 3, PC is equipped with the 3D virtual software, sets virtual objects corresponding to tested control system 4 by the 3D virtual software in PC; Virtual objects moves or provides corresponding signal to tested control system 4 according to the signal of tested control system 4.
Above embodiment is one of preferred plan of the present utility model, is not that the utility model is done any pro forma restriction, also has other variant and remodeling under the prerequisite that does not exceed the technical scheme that claim puts down in writing.
Claims (8)
1. virtual measuring and controling system, comprise interface circuit and virtual emulation equipment, described virtual emulation equipment links to each other with tested control system by described interface circuit, it is characterized in that: described interface circuit comprises processor, analog to digital conversion circuit, the duty ratio measuring circuit, the adjustment circuit is amplified in input, T type change-over circuit, 24 A/D convertor circuits, the adjustment circuit is amplified in output, D/A converting circuit, the switching value change-over circuit, communication interface and terminal, the signal output part of described tested control system by described terminal respectively with described duty ratio measuring circuit, the adjustment circuit is amplified in input, the input end of T type change-over circuit links to each other, described duty ratio measuring circuit, input is amplified the output terminal of adjusting circuit and is linked to each other with the input end of analog-digital conversion circuit as described, the output terminal of analog-digital conversion circuit as described links to each other with the input end of described processor, the output terminal of described T type change-over circuit links to each other with the input end of described 24 A/D convertor circuits, the output terminal of described 24 A/D convertor circuits links to each other with the input end of described processor, the output terminal of described processor respectively with described D/A converting circuit, the input end of switching value change-over circuit links to each other, the output terminal of described D/A converting circuit amplifies the input end of adjusting circuit with described output and links to each other, and the output terminal of adjustment circuit is amplified in described output and the output terminal of described switching value change-over circuit links to each other with the input end of described tested control system by described terminal respectively; Described processor links to each other with described virtual emulation equipment by described communication interface; Described emulator comprises PC.
2. a kind of virtual measuring and controling system according to claim 1 is characterized in that: described duty ratio measuring circuit comprises the voltage-controlled low pass active filter circuit of holding circuit, current rectifying and wave filtering circuit and single supply; Described holding circuit is made up of diode D1; described current rectifying and wave filtering circuit is made up of diode D2, capacitor C 1, resistance R 1; described PWM input signal; send diode D2, capacitor C 1 and resistance R 1 to carry out rectifying and wave-filtering through the D1 pressure limiting, export the direct current signal of 0-5V then by the voltage-controlled low pass active filter circuit of the described single supply of forming by resistance R 2, R3, R4, R5, capacitor C 2, C3 and operational amplifier A 1.
3. a kind of virtual measuring and controling system according to claim 1 and 2 is characterized in that: described input is amplified the adjustment circuit 0-24V voltage signal and 0-20mA current signal is converted to the 0-5V voltage signal.
4. a kind of virtual measuring and controling system according to claim 1 and 2, it is characterized in that: described T type change-over circuit comprises several T type circuit, operational amplifier A 30, resistance R 30 and diode D21, described T type circuit comprises resistance R 20, R21, R22, diode D20, triode Q20, and the resistance of the described resistance R 20 of the resistance value ratio of wherein said resistance R 21 is twice; One end of described resistance R 20 links to each other with an end of described resistance R 21, the other end of resistance R 21 links to each other with the positive pole of described diode D20, the collector of described triode Q20 respectively, the emitter of described triode Q20 links to each other with ground, and the base stage of described triode Q20 links to each other with described tested control system as signal input part by described resistance R 22; When T type circuit connects, the other end of the resistance R 20 of the described T type of first via circuit links to each other with positive source, resistance R 20 in the other end of the resistance R 20 of each road T type circuit of back and front one road T type circuit and the tie point of R21 are connected, and the resistance R 20 of last road T type circuit links to each other with ground by described diode D21; The negative pole of the diode D20 of each road T type circuit links together and links to each other with the input cathode of described operational amplifier A 30, the input anode of described operational amplifier A 30 links to each other with ground, one end of described resistance R 30 links to each other with the input cathode of described operational amplifier A 30, and the other end of described resistance R 30 links to each other with the output terminal of described operational amplifier A 30.
5. a kind of virtual measuring and controling system according to claim 4 is characterized in that: described 24 A/D convertor circuits are LTC2400 chips.
6. a kind of virtual measuring and controling system according to claim 1 and 2 is characterized in that: 24 A/D convertor circuits of described 24 A/D convertor circuits are LTC2400 chips.
7. a kind of virtual measuring and controling system according to claim 1 and 2 is characterized in that: described communication interface comprises the RS232 serial ports.
8. a kind of virtual measuring and controling system according to claim 1 and 2 is characterized in that: described communication interface comprises USB interface.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011200303843U CN202049354U (en) | 2011-01-28 | 2011-01-28 | Virtual measurement and control system |
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| CN2011200303843U CN202049354U (en) | 2011-01-28 | 2011-01-28 | Virtual measurement and control system |
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| CN202049354U true CN202049354U (en) | 2011-11-23 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103761207A (en) * | 2013-06-25 | 2014-04-30 | 严俊 | Measurement and control system for 3D virtual device |
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2011
- 2011-01-28 CN CN2011200303843U patent/CN202049354U/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103761207A (en) * | 2013-06-25 | 2014-04-30 | 严俊 | Measurement and control system for 3D virtual device |
| CN103761207B (en) * | 2013-06-25 | 2016-08-10 | 严俊 | A kind of 3D virtual unit TT&C system |
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Granted publication date: 20111123 Termination date: 20120128 |