CN108681275B - Output voltage parametric compensation method and device for voltage linear isolation conditioning circuit - Google Patents
Output voltage parametric compensation method and device for voltage linear isolation conditioning circuit Download PDFInfo
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- CN108681275B CN108681275B CN201810401205.9A CN201810401205A CN108681275B CN 108681275 B CN108681275 B CN 108681275B CN 201810401205 A CN201810401205 A CN 201810401205A CN 108681275 B CN108681275 B CN 108681275B
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- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/04—Programme control other than numerical control, i.e. in sequence controllers or logic controllers
- G05B19/042—Programme control other than numerical control, i.e. in sequence controllers or logic controllers using digital processors
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- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
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Abstract
The invention relates to a voltage linear isolation conditioning circuit output voltage parametric compensation method and device, and belongs to the field of voltage signal acquisition compensation. The method comprises the following steps: obtaining the output voltage of at least one path of voltage linear isolation conditioning circuit; reading output voltage compensation parameters corresponding to the at least one path of voltage linear isolation conditioning circuit from prestored output voltage compensation parameters; and respectively compensating the obtained output voltage of the at least one path of voltage linear isolation conditioning circuit by using the read output voltage compensation parameters to obtain the compensated voltage of the at least one path of voltage linear isolation conditioning circuit. The invention solves the problems of complicated process, poor stability and need of regular calibration in the existing compensation method and device.
Description
Technical Field
The invention relates to the technical field of voltage signal processing, in particular to a voltage linear isolation conditioning circuit output voltage parametric compensation method and device.
Background
In many industrial measurements such as automatic detection systems, computer data acquisition systems, industrial control systems, etc., it is often necessary to acquire multiple paths of field analog signals into a microprocessor. During the collection process, various interference signals enter the microprocessor along with the measured signals, the superposition of the signals on the useful measured signals can reduce the accuracy of measurement, and in order to realize voltage linear conversion and not introduce field electric noise interference into a control system, a measured circuit and a control circuit must be electrically isolated and conditioned.
At present, a voltage isolation conditioning circuit based on a linear optocoupler is used more, and the circuit enables output voltage to be equal to input voltage by selecting an input resistor and an output resistor with the same resistance value. However, since the parameters of the electronic components have discreteness, in the high-precision voltage acquisition system, two resistors with matched resistance values must be selected by repeated debugging, so as to compensate errors caused by the parameters of the circuit components, which takes long time, has low efficiency and low success rate.
Disclosure of Invention
In view of the above analysis, the present invention aims to provide a parameterized compensation method and apparatus for output voltage of a voltage linear isolation conditioning circuit, which solves the problems of low efficiency and low success rate in the current isolation conditioning process of collecting voltage.
The purpose of the invention is mainly realized by the following technical scheme:
on one hand, the embodiment of the invention provides the method for obtaining the output voltage of at least one path of voltage linear isolation conditioning circuit;
reading output voltage compensation parameters corresponding to the at least one path of voltage linear isolation conditioning circuit from prestored output voltage compensation parameters;
and respectively compensating the obtained output voltage of the at least one path of voltage linear isolation conditioning circuit by using the read output voltage compensation parameters to obtain the compensated voltage of the at least one path of voltage linear isolation conditioning circuit.
On the basis of the scheme, any one output voltage compensation parameter in the prestored output voltage compensation parameters is determined according to the ratio of the voltage at the input end of the linear isolation conditioning circuit to the voltage at the output end of the linear isolation conditioning circuit.
On the basis of the scheme, each output voltage in the at least one path of voltage linear isolation conditioning circuit is multiplied by the output voltage compensation parameter to obtain the voltage compensated by the at least one path of voltage linear isolation conditioning circuit.
On the basis of the scheme, the method further comprises the step of outputting the voltage compensated by the voltage linear isolation conditioning circuit.
On the basis of the above scheme, the obtaining of the output voltage of the at least one voltage linear isolation conditioning circuit includes:
on the basis of the scheme, each path of output of the voltage linear isolation conditioning circuit to be acquired is acquired for multiple times to obtain multiple acquisition results;
on the basis of the scheme, the root mean square filtering is carried out on the multiple acquisition results of each voltage linear isolation conditioning circuit, so as to obtain the output voltage of each voltage linear isolation conditioning circuit.
In a second aspect, there is provided a voltage linear isolation conditioning circuit output voltage parameterized compensation apparatus, including:
the AD acquisition module is used for acquiring the output voltage of at least one path of voltage linear isolation conditioning circuit;
the reading module is used for reading the output voltage compensation parameters corresponding to the at least one path of voltage linear isolation conditioning circuit from the prestored output voltage compensation parameters;
and the voltage compensation module is used for respectively compensating the obtained output voltage of the at least one path of voltage linear isolation conditioning circuit by using the read output voltage compensation parameters to obtain the voltage compensated by the at least one path of voltage linear isolation conditioning circuit.
On the basis of the scheme, the device further comprises a memory, wherein the memory is used for storing the output voltage compensation parameter; and any one path of the output voltage compensation parameter is determined according to the ratio of the voltage of the input end of the voltage linear isolation conditioning circuit to the voltage of the output end.
On the basis of the above scheme, the voltage compensation module is configured to multiply the output voltage of each path by the output voltage compensation parameter of the path to obtain the voltage compensated by the at least one path of voltage linear isolation conditioning circuit.
On the basis of the scheme, the voltage linear isolation conditioning circuit further comprises a communication module which is used for outputting the voltage compensated by the voltage linear isolation conditioning circuit to an upper computer.
On the basis of the scheme, the memory is a FLASH chip; respectively storing the compensation parameters in different memory units in the FLASH chip through write operation; and reading the corresponding output voltage compensation parameters from the memory unit of the FLASH chip through reading operation during query. .
The beneficial effects of the above scheme are as follows:
the method has the advantages that a parameterized compensation mode is adopted, errors caused by the parameter discreteness of the electronic components are made up, the operation is simple and easy, the errors caused by the parameter discreteness of the electronic components such as resistors or linear optocouplers in the existing circuit are solved, and the problems that in the traditional method, the long and complicated calibration process is needed through fixed resistance value matching, the resistance value is unstable after the calibration through an adjustable resistor, and the calibration needs to be carried out periodically during the use are solved.
Accurate compensation is carried out on each path of voltage linear isolation conditioning circuit, the collection of the output voltage of the multi-path voltage linear isolation conditioning circuit can be simultaneously realized, and the efficiency is improved.
The compensation parameters are set at one time, so that the follow-up regular adjustment is not needed, the operation process is simple and easy to implement, and the reliability is high. The voltage acquisition precision is improved, and the production efficiency is also improved.
The method and the device are based on the same principle, so the same technical effect can be achieved.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
Drawings
The drawings are only for purposes of illustrating particular embodiments and are not to be construed as limiting the invention, wherein like reference numerals are used to designate like parts throughout.
FIG. 1 is a flow chart of a method according to an embodiment of the present invention;
FIG. 2 is a diagram illustrating an apparatus according to an embodiment of the present invention.
Detailed Description
The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form a part hereof, and which together with the embodiments of the invention serve to explain the principles of the invention.
Method embodiment
As shown in fig. 1, the present embodiment relates to a parameterized compensation method for output voltage of a voltage linear isolation conditioning circuit, which includes the following steps:
and step S1, obtaining the output voltage of at least one path of voltage linear isolation conditioning circuit.
The output voltage of the M voltage linear isolation conditioning circuits is collected at the same time, the collection of the power voltage of 1 or more circuits of the system can be completed at the same time, M is more than or equal to 1 and less than or equal to N, and N circuits can be reached at most, so that the collection efficiency and the adaptability are improved. And N is the number of prestored output voltage compensation parameters, namely the total number of the corresponding voltage linear isolation conditioning circuits.
And (3) storing the compensation parameters of all the voltage linear isolation conditioning circuits (marked as N paths) in advance, selecting one or more paths of the compensation parameters according to actual acquisition requirements to acquire the voltage, and compensating.
Optionally, the AD acquisition module acquires the output voltage of at least one voltage linear isolation conditioning circuit to obtain a digital voltage, which is convenient for subsequent compensation operation.
The single-point acquisition may cause inaccurate results due to interference or burrs, and in order to improve the accuracy of voltage acquisition, multiple acquisition of each output voltage may be selected, and root mean square filtering may be performed on multiple acquisition results to obtain a voltage value from which interference is eliminated, and the voltage value is used as the output voltage of the path.
Specifically, an AD acquisition module is adopted to acquire the output of each path of voltage linear isolation conditioning circuit needing to be compensated for multiple times, so that multiple acquisition results are obtained; and performing root mean square filtering on the multiple acquisition results of each voltage linear isolation conditioning circuit to obtain the output voltage of each voltage linear isolation conditioning circuit so as to solve the problem of inaccurate results caused by interference or burrs when the AD acquisition module is adopted for acquisition.
And step S2, reading the pre-stored output voltage compensation parameters to obtain the output voltage compensation parameters corresponding to the at least one path of voltage linear isolation conditioning circuit.
The compensation parameters are stored in advance once, and adjustment is not needed subsequently, so that the efficiency and the reliability are improved.
In specific implementation, N output voltage compensation parameters are stored in advance, wherein the output voltage compensation parameters can be obtained in the following manner:
voltages Vin1 to VinN are loaded on input ends of the N voltage linear isolation conditioning circuits (1) respectively, and Vin1 to VinN are used as theoretical values of output voltages of the N voltage linear isolation conditioning circuits (1) and can be provided by a power supply outside a system;
testing to obtain voltage values of output ports of the N voltage linear isolation conditioning circuits (1), and respectively recording the voltage values as X1-XN, and taking X1-XN as actual values of output voltages of the N voltage linear isolation conditioning circuits (1);
and obtaining the output voltage compensation parameters K1-KN of each voltage linear isolation conditioning circuit (1) through the ratio of the theoretical value and the actual value of each output voltage.
The specific calculation formula can be expressed as: ki is Vini/Xi, wherein i is 1 to N.
Optionally, a multimeter or other voltage measuring equipment is used to obtain the theoretical value and the actual value of the output voltage of the N voltage linear isolation conditioning circuits, and a person skilled in the art can understand that any way of obtaining the voltage values can be applied to the present invention, and the same effect can be achieved.
In order to improve the accuracy of each pre-stored output voltage compensation parameter, when the output voltage compensation parameters of the N voltage linear isolation conditioning circuits are obtained, the theoretical value and the actual value of the output voltage of each voltage linear isolation conditioning circuit are obtained by averaging multiple acquisition results.
And storing the N paths of compensation parameters obtained by calculation. In order to ensure the non-loss property of the storage result, the component with the data storage function after power failure can be selected at will.
Illustratively, off-chip or on-chip memory completion may be selected. Preferably, the FLASH chip is selected, and the compensation parameters are written into the FLASH chip through the FLASH read-write control module and are stored. The FLASH chip is a power-down nonvolatile memory, and continuous utilization of data is guaranteed.
Optionally, the N-path compensation parameters may be stored in a form of a table or a data pair, and any storage manner that can clearly indicate the correspondence between each path of voltage linear isolation conditioning circuit and the path of compensation parameters can be applied to the present invention.
The compensation parameters corresponding to the multi-path voltage linear isolation conditioning circuit can be found from the pre-stored N paths of compensation parameters in an addressing or retrieval mode, and the compensation parameters are read out and used for subsequent compensation.
Preferably, the N-channel compensation parameters are respectively stored in N different memory units in the FLASH chip (or other power-down nonvolatile memory) through write operation (for example, from the No. 1 memory unit to the No. N memory unit in the FLASH chip, each memory unit stores one compensation parameter); and acquiring the compensation parameters of the corresponding path from the memory unit of the FLASH chip through reading operation during query, and using the compensation parameters to compensate the output voltage of the corresponding acquisition channel.
And step S3, respectively compensating the obtained output voltage of the at least one path of voltage linear isolation conditioning circuit by using the read output voltage compensation parameters to obtain the compensated voltage of the at least one path of voltage linear isolation conditioning circuit.
In particular, output voltage compensation may be performed by the processor chip (3). The voltage values of M AD ports output by the M voltage linear isolation conditioning circuit (1) are read through the AD acquisition module (5), meanwhile, corresponding M compensation parameters stored in the FLASH chip (2) are read through the FLASH read-write control module (6) at the FLASH read-write control port, and are correspondingly multiplied by the M voltage values read by the AD acquisition module (5), so that compensated voltage acquisition results are recorded as Vo 1-VoM, and the M voltage compensation and acquisition processes are completed.
In order to meet the requirement of industrial measurement, the voltage compensated by the M-path voltage linear isolation conditioning circuit can be output on the basis of the scheme, the output can be realized through a data communication module (7), and according to different communication modes, a specific data communication module (7) can be selected, such as a wireless communication module, a Bluetooth module, a wired communication module and the like.
In this embodiment:
the method has the advantages that a parameterized compensation mode is adopted, errors caused by the parameter discreteness of the electronic components are made up, the operation is simple and easy, the errors caused by the parameter discreteness of the electronic components such as resistors or linear optocouplers in the existing circuit are solved, and the problems that in the traditional method, the long and complicated calibration process is needed through fixed resistance value matching, the resistance value is unstable after the calibration through an adjustable resistor, and the calibration needs to be carried out periodically during the use are solved.
Accurate compensation is carried out on each path of voltage linear isolation conditioning circuit, the collection of the output voltage of the multi-path voltage linear isolation conditioning circuit can be simultaneously realized, and the efficiency is improved.
The compensation parameters are set at one time, so that the follow-up regular adjustment is not needed, the operation process is simple and easy to implement, and the reliability is high. The voltage acquisition precision is improved, and the production efficiency is also improved.
Device embodiment
As shown in fig. 2, the present embodiment provides a parameterized compensation apparatus for output voltage of a voltage linear isolation conditioning circuit, which is used to implement any one of the compensation methods in the above embodiments.
The compensation device comprises an AD acquisition module, a voltage compensation module and a voltage compensation module, wherein the AD acquisition module is used for acquiring the output voltage of at least one path of voltage linear isolation conditioning circuit; the reading module is used for reading the output voltage compensation parameters corresponding to the at least one path of voltage linear isolation conditioning circuit from the prestored output voltage compensation parameters; and the voltage compensation module is used for respectively compensating the obtained output voltage of the at least one path of voltage linear isolation conditioning circuit by using the read output voltage compensation parameters to obtain the voltage compensated by the at least one path of voltage linear isolation conditioning circuit.
And the AD acquisition modules are respectively used for acquiring the output voltages of the M voltage linear isolation conditioning circuits and performing analog-to-digital conversion processing. M is more than or equal to 1 and less than or equal to N, and N is the total number of the voltage linear isolation conditioning circuits.
The voltage compensation module is realized by adopting a processor chip, and the reading module is a FLASH read-write control module. N paths of output voltage compensation parameters are stored in a memory in advance; the memory is preferably a FLASH chip.
It should be understood by those skilled in the art that any processor chip having an AD pin or capable of being externally connected to an AD chip can be applied to the present invention, and optionally, the present embodiment adopts a DSP2812 chip, and there are 16 AD pins on the chip, that is, under the condition that an external AD chip is not added, compensation for 16 channels of collected voltages can be realized. According to actual needs, the number of channels can be increased in an external expansion AD chip mode, the compensation of the voltage of more voltage linear isolation conditioning circuits can be achieved, and the compensation of the voltage linear isolation conditioning circuits corresponding to the external expansion channels can be achieved only by storing compensation parameters of the voltage linear isolation conditioning circuits in advance.
During specific implementation, when the AD acquisition module acquires voltage, the processor chip reads corresponding compensation parameters through the FLASH read-write control module at the FLASH read-write control port, and the compensated voltage is obtained after supplementary operation is performed through the processor chip.
In order to realize the transmission and subsequent use of the compensated voltage, the compensation device further comprises a communication module which is used for outputting the voltage compensated by the M-path voltage linear isolation conditioning circuit to an upper computer. The communication module outputs the compensated voltage to a communication interface circuit (4) through an SCI interface, and the communication interface circuit transmits the M paths of compensated voltage to an upper computer.
It should be noted that the method embodiments and the apparatus embodiments are based on the same principle, and the same or similar parts can be referred to each other and achieve the same technical effects.
Those skilled in the art will appreciate that all or part of the flow of the method implementing the above embodiments may be implemented by a computer program, which is stored in a computer readable storage medium, to instruct related hardware. The computer readable storage medium is a magnetic disk, an optical disk, a read-only memory or a random access memory.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention.
Claims (6)
1. A parameterized compensation method for output voltage of a voltage linear isolation conditioning circuit is characterized by comprising the following steps:
obtaining the output voltage of at least one path of voltage linear isolation conditioning circuit;
obtaining the output voltage of the at least one path of voltage linear isolation conditioning circuit through a multimeter or other voltage measuring equipment;
reading output voltage compensation parameters corresponding to the at least one path of voltage linear isolation conditioning circuit from prestored output voltage compensation parameters;
the pre-stored output voltage compensation parameters comprise a plurality of paths, wherein any path of output voltage compensation parameter is determined according to the ratio of the voltage at the input end of the linear isolation conditioning circuit to the voltage at the output end of the linear isolation conditioning circuit;
and respectively compensating the acquired output voltage of each voltage linear isolation conditioning circuit by using the read output voltage compensation parameter, and multiplying the acquired output voltage of each voltage linear isolation conditioning circuit by the output voltage compensation parameter to obtain the voltage compensated by each voltage linear isolation conditioning circuit.
2. The parametric compensation method of claim 1, wherein: and outputting the voltage compensated by the voltage linear isolation conditioning circuit.
3. The parametric compensation method according to one of claims 1-2, wherein: the obtaining of the output voltage of the at least one voltage linear isolation conditioning circuit comprises:
collecting each path of output of the voltage linear isolation conditioning circuit to be acquired for multiple times to obtain multiple collection results;
and performing root mean square filtering on the multiple acquisition results of each voltage linear isolation conditioning circuit to obtain the output voltage of each voltage linear isolation conditioning circuit.
4. A voltage linear isolation conditioning circuit output voltage parameterization compensation device is characterized by comprising:
the AD acquisition module is used for acquiring the output voltage of at least one path of voltage linear isolation conditioning circuit;
the reading module is used for reading the output voltage compensation parameters corresponding to the at least one path of voltage linear isolation conditioning circuit from the prestored output voltage compensation parameters;
a memory for storing the output voltage compensation parameter; any one path of the output voltage compensation parameter is determined according to the ratio of the voltage of the input end of the voltage linear isolation conditioning circuit to the voltage of the output end;
and the voltage compensation module is used for respectively compensating the obtained output voltage of the at least one path of voltage linear isolation conditioning circuit by using the read output voltage compensation parameter, and multiplying each path of output voltage by the output voltage compensation parameter to obtain the voltage compensated by the at least one path of voltage linear isolation conditioning circuit.
5. The parametric compensation device of claim 4, wherein: the voltage linear isolation conditioning circuit is used for compensating the voltage of the voltage linear isolation conditioning circuit and outputting the compensated voltage to an upper computer.
6. The parametric compensation device of claim 4, wherein: the memory is a FLASH chip; respectively storing the compensation parameters in different memory units in the FLASH chip through write operation; and reading the corresponding output voltage compensation parameters from the memory unit of the FLASH chip through reading operation.
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| CN201810401205.9A CN108681275B (en) | 2018-04-28 | 2018-04-28 | Output voltage parametric compensation method and device for voltage linear isolation conditioning circuit |
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| CN201810401205.9A CN108681275B (en) | 2018-04-28 | 2018-04-28 | Output voltage parametric compensation method and device for voltage linear isolation conditioning circuit |
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| CN108681275B true CN108681275B (en) | 2020-03-17 |
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| CN2872495Y (en) * | 2005-12-27 | 2007-02-21 | 李斌 | Analog signal converting and isolating module |
| CN101076053B (en) * | 2007-06-21 | 2010-10-06 | 吴壬华 | Method and circuit for multi-channel photoelectric isolated voltage |
| CN103596319B (en) * | 2012-08-14 | 2015-05-27 | 华润矽威科技（上海）有限公司 | A non-isolated LED driving system and a non-isolated LED driving constant-current control circuit |
| CN103235202B (en) * | 2012-08-20 | 2016-01-20 | 苏州大学 | A kind of multichannel analog signals acquisition system with automatic compensation function |
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