CN101936746B - Non-electric quantity determination system and method - Google Patents

Non-electric quantity determination system and method Download PDF

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Publication number
CN101936746B
CN101936746B CN2010102430966A CN201010243096A CN101936746B CN 101936746 B CN101936746 B CN 101936746B CN 2010102430966 A CN2010102430966 A CN 2010102430966A CN 201010243096 A CN201010243096 A CN 201010243096A CN 101936746 B CN101936746 B CN 101936746B
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China
Prior art keywords
signal value
electrical quantities
temperature signal
value
order nonlinear
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Expired - Fee Related
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CN2010102430966A
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Chinese (zh)
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CN101936746A (en
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常先明
徐昭敏
陈小枫
耿东汉
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BEIJING HUAKONG TECHNOLOGY Co Ltd
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BEIJING HUAKONG TECHNOLOGY Co Ltd
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Abstract

The invention discloses a non-electric quantity determination system and a non-electric quantity determination method, which are used for determining a non-electric quantity. In the system and the method of the invention, relationships between the detected non-electric quantity and a frequency signal value and between the detected non-electric quantity and a temperature signal value are described by high-order nonlinear characteristic equations, and simultaneously, coefficients of the high-order nonlinear equations are calculated by a large amount of data fitting by using a high-order non-linear fitting algorithm, so the detection accuracy is ensured, and the condition of low detection accuracy caused by piecewise linear methods is avoided.

Description

A kind of non-electrical quantities is measured system and method
Technical field
The present invention relates to non-electrical quantities and measure the field, relate to a kind of non-electrical quantities more precisely and measure system and method.
Background technology
Capacitive transducer is widely used, but capacitive transducer has characteristic of nonlinear, and its nonlinear characteristic changes with variation of temperature.
In order to guarantee the accuracy of detection of capacitive transducer, in the prior art, use piecewise linear method at normal temperatures and draw the broken line relation between input signal and the output signal.Be: input signal is divided into plurality of sections; Can think on each section that between input signal and the output signal be linear relationship; For this tittle; In whole range ability, be non-linear, but just within a certain subrange of input, its output signal and input signal can be similar to thinks linear relationship.Number of fragments is many more, and accuracy of detection is high more.
But in practical application, can increase cost because increase the quantity of segmentation, so the quantity of segmentation is unsuitable too many, thereby the precision of use piecewise linearity method can not be very high.
Summary of the invention
In view of this, the invention provides a kind of non-electrical quantities and measure system and method, need not carry out staged operation, can reduce cost and accuracy of detection higher.
The invention provides a kind of non-electrical quantities and measure system, comprising:
Gather non-electrical quantities and convert the capacitive transducer of capacitance signal value into;
Connect said capacitive transducer, said capacitance signal value converted into the frequency translation module of frequency signal value;
The temperature collect module of collecting temperature signal value;
The micro-control unit MCU module that connects said frequency translation module and temperature collect module, this MCU module is handled said frequency signal value and said temperature signal value according to preset high-order nonlinear secular equation, obtains the value of said non-electrical quantities.
Preferably, said preset high-order nonlinear secular equation does
Y=F 4*(A1*T 4+A2*T 3+A3*T 2+A4*T+A5)+
F 3*(B?1*T 4+B2*T 3+B3*T 2+B4*T+B5)+
F 2*(C?1*T 4+C2*T 3+C3*T 2+C4*T+C5)+
F*(D1*T 4+D2*T 3+D3*T 2+D4*T+D5)+
(E1*T 4+E2*T 3+E3*T 2+E4*T+E5),
Wherein, Y is the calculated value of said non-electrical quantities, and F is said frequency signal value, and T is said temperature signal value, and A1~A5, B1~B5, C1~C5, D1~D5 and E1~E5 are the coefficient of said high-order nonlinear secular equation.
Preferably, said frequency translation module is the RC oscillatory circuit.
Preferably, system provided by the invention also comprises: the digital interface module, the calculated value of said non-electrical quantities is through the output of digital interface module.
Preferably, said digital interface module is a Serial Peripheral Interface SPI module.
The present invention also provides a kind of non-electrical quantities assay method, comprising:
Gather a plurality of known non-electrical quantities, a plurality of temperature signal value and a plurality of frequency signal value that converts through capacitance signal by said known non-electrical quantities;
Said known non-electrical quantities, temperature signal value and frequency signal value are imported the high-order nonlinear secular equation that contains undetermined coefficient between said non-electrical quantities and frequency signal value, the temperature signal value and utilized the high-order nonlinear fitting algorithm to calculate the undetermined coefficient of high-order nonlinear secular equation;
Gather unknown non-electrical quantities and convert said non-electrical quantities into the capacitance signal value, convert said capacitance signal value into the frequency signal value again, the collecting temperature signal value;
Said temperature signal value and the substitution of frequency signal value have been confirmed the said high-order nonlinear secular equation of coefficient and calculated the value of the non-electrical quantities of said the unknown.
Preferably, said high-order nonlinear secular equation does
Y=F 4*(A1*T 4+A2*T 3+A3*T 2+A4*T+A5)+
F 3*(B1*T 4+B2*T 3+B3*T 2+B4*T+B5)+
F 2*(C1*T 4+C2*T 3+C3*T 2+C4*T+C5)+
F*(D1*T 4+D2*T 3+D3*T 2+D4*T+D5)+
(E1*T 4+E2*T 3+E3*T 2+E4*T+E5)
Wherein, Y is the calculated value of non-electrical quantities, and F is said frequency signal value, and T is said temperature signal value, and A1~A5, B1~B5, C1~C5, D1~D5 and E1~E5 are the coefficient of said high-order nonlinear secular equation.
Preferably, a plurality of known non-electrical quantities of said collection, a plurality of temperature signal value and a plurality of frequency signal value that is converted through capacitance signal by said known non-electrical quantities are to gather to be not less than 100,000 known non-electrical quantities, to be not less than 100,000 temperature signal value and to be not less than 100,000 frequency signal values that converted through capacitance signal by said known non-electrical quantities.
Preferably, the process of a plurality of temperature signal value of said collection comprises:
Change environment temperature according to preset rule, gather the temperature signal value under the varying environment temperature respectively.
Preferably, said a plurality of known non-electrical quantities numerically evenly distributes; Said a plurality of temperature signal value was evenly distributed on the time of gathering.
Preferably, said a plurality of known non-electrical quantities is an integer; Said a plurality of temperature signal value is an integer.
A kind of non-electrical quantities provided by the invention is measured system and method and can non-electrical quantities be transformed to the frequency signal value; And collecting temperature signal value; Said frequency quantity and temperature are imported the said high-order nonlinear secular equation of confirming coefficient, calculate the non-electrical quantities that is detected.Because what the present invention adopted is the high-order nonlinear secular equation, need not carry out segmentation and calculate, can reduce cost.And, owing to the coefficient of high-order nonlinear secular equation calculates with the high-order nonlinear fitting algorithm according to lot of data, so precision is higher.
Description of drawings
In order to be illustrated more clearly in the embodiment of the invention or technical scheme of the prior art; To do to introduce simply to the accompanying drawing of required use in embodiment or the description of the Prior Art below; Obviously, the accompanying drawing in describing below only is some embodiments of the present invention, for those of ordinary skills; Under the prerequisite of not paying creative work, can also obtain other accompanying drawing according to these accompanying drawings.
Fig. 1 is that a kind of non-electrical quantities of the embodiment of the invention one is measured system;
Fig. 2 is definite method of the high-order nonlinear secular equation coefficient of the embodiment of the invention one;
Fig. 3 is that a kind of non-electrical quantities of the embodiment of the invention two is measured system;
Fig. 4 is that a kind of non-electrical quantities of the embodiment of the invention three is measured system;
Fig. 5 is a kind of non-electrical quantities assay method of the embodiment of the invention four.
Embodiment
To combine the accompanying drawing in the embodiment of the invention below, the technical scheme in the embodiment of the invention is carried out clear, intactly description, obviously, described embodiment only is the present invention's part embodiment, rather than whole embodiment.Based on the embodiment among the present invention, those of ordinary skills are not making the every other embodiment that is obtained under the creative work prerequisite, all belong to the scope of the present invention's protection.
Understand for convenient, existing to some making an explanation property of vocabulary explanation:
The high-order nonlinear fitting algorithm: a certain high-order nonlinear secular equation that contains undetermined coefficient of hypothesis meets characteristic curve between each parameter or curved surface in the said secular equation earlier; Gather a large amount of each known supplemental characteristic then; Utilize the matlab The Fitting Calculation to go out the numerical value of the undetermined coefficient of said secular equation, thereby confirm the secular equation of each parameter.In said high-order nonlinear fitting algorithm, the data of collection are many more, and the DATA DISTRIBUTION of collection is even more, and described characteristic curve of then confirming of secular equation or curved surface are more near characteristic curve real between each parameter or curved surface.
MCU: be the abbreviation of English Micro Control Unit, the Chinese meaning is a micro-control unit.
SPI: be the abbreviation of English Serial Peripheral Interface, the Chinese meaning is a Serial Peripheral Interface.
With reference to Fig. 1, for a kind of non-electrical quantities of the embodiment of the invention one is measured system.
As shown in Figure 1, the described a kind of non-electrical quantities mensuration of present embodiment system comprises: capacitive sensor modules 101, frequency translation module 102, temperature collect module 103, MCU module 104;
Said capacitive sensor modules 101 is gathered non-electrical quantities; And convert the capacitance signal value into and export to frequency translation module 102; Said frequency translation module 102 converts said capacitance signal value the frequency signal value into and exports to said MCU module 104; Said temperature collect module 103 collecting temperature signal values; And the temperature signal value that obtains exported to said MCU module 104, said MCU module 104 is brought said frequency signal value, temperature signal value between said non-electrical quantities and said frequency signal value, the temperature signal value high-order nonlinear secular equation
Y=F 4*(A1*T 4+A2*T 3+A3*T 2+A4*T+A5)+
F 3*(B1*T 4+B2*T 3+B3*T 2+B4*T+B5)+
F 2*(C1*T 4+C2*T 3+C3*T 2+C4*T+C5)+
F*(D1*T 4+D2*T 3+D3*T 2+D4*T+D5)+
(E1*T 4+E2*T 3+E3*T 2+E4*T+E5),
And calculate the numerical value 3 of said non-electrical quantities
Wherein, Y is the calculated value of said non-electrical quantities, and F is said frequency signal value, and T is said temperature signal value, and A1~A5, B1~B5, C1~C5, D1~D5 and E1~E5 are the coefficient of said high-order nonlinear secular equation.
In the said high-order nonlinear secular equation; Said frequency signal value F and said temperature signal value T are known; Obtain the value of said non-electrical quantities, also need confirm coefficient A1~A5, B1~B5, C1~C5, D1~D5 and the E1~E5 of said high-order nonlinear secular equation.
With reference to Fig. 2, be definite method of the high-order nonlinear secular equation coefficient of the embodiment of the invention one.
This method comprises:
Gather a plurality of known non-electrical quantities, a plurality of temperature signal value and a plurality of frequency signal value that converts through the capacitance signal value by non-electrical quantities;
Said known non-electrical quantities, temperature signal value and frequency signal value are imported the high-order nonlinear secular equation that contains undetermined coefficient between said non-electrical quantities and frequency signal value, the temperature signal value
Y=F 4*(A1*T 4+A2*T 3+A3*T 2+A4*T+A5)+
F 3*(B1*T 4+B2*T 3+B3*T 2+B4*T+B5)+
F 2*(C1*T 4+C2*T 3+C3*T 2+C4*T+C5)+
F*(D1*T 4+D2*T 3+D3*T 2+D4*T+D5)+
(E1*T 4+E2*T 3+E3*T 2+E4*T+E5)
And utilize the high-order nonlinear fitting algorithm to calculate the coefficient of said high-order nonlinear secular equation;
Wherein, Y is the calculated value of said non-electrical quantities, and F is said frequency signal value, and T is said temperature signal value, and A1~A5, B 1~B5, C1~C5, D1~D5 and E1~E5 are the coefficient of said high-order nonlinear secular equation.
The described system of present embodiment can be transformed to the frequency signal value with non-electrical quantities, and the collecting temperature signal value, and said frequency signal value and temperature signal value are imported the said high-order nonlinear secular equation of confirming coefficient, calculates said non-electrical quantities.Because what the present invention adopted is the high-order nonlinear fitting algorithm, need not carry out staged operation, can reduce cost, and precision is higher.
With reference to Fig. 3, for a kind of non-electrical quantities of the embodiment of the invention two is measured system.As shown in Figure 3, the difference that the described a kind of non-electrical quantities of present embodiment is measured system and embodiment one described system is that also comprise digital interface module 105, said frequency translation module is a RC oscillatory circuit 102.
In addition, the said system of present embodiment is identical with embodiment one said system.
Said capacitive sensor modules 101 is gathered non-electrical quantities; And convert the capacitance signal value into and export to RC oscillatory circuit 102; Said RC oscillatory circuit 102 converts said capacitance signal value the frequency signal value into and exports to said MCU module 104; Said temperature collect module 103 collecting temperature signal values, and the temperature signal value that obtains exported to said MCU module 104.Said MCU module 104 is after calculating the numerical value of said non-electrical quantities, through the numerical value of the said non-electrical quantities of digital interface module 105 outputs.
With reference to Fig. 4, for a kind of non-electrical quantities of the embodiment of the invention three is measured system.
As shown in Figure 4, the difference that the described a kind of non-electrical quantities of present embodiment is measured system and embodiment two described systems is that said digital interface module is a SPI module 105.The numerical value of said non-electrical quantities is through said SPI module 105 outputs.
In addition, the said system of present embodiment is identical with embodiment two said systems.
With reference to Fig. 5, be a kind of non-electrical quantities assay method of the embodiment of the invention four.
As shown in Figure 5, the described method of present embodiment comprises:
Gather a plurality of known non-electrical quantities, a plurality of temperature signal value and a plurality of frequency signal value that converts through the capacitance signal value by non-electrical quantities;
The high-order nonlinear secular equation that contains undetermined coefficient between non-electrical quantities that said known non-electrical quantities, temperature signal value and the input of frequency signal value are detected and frequency signal value, the temperature signal value
Y=F 4*(A1*T 4+A2*T 3+A3*T 2+A4*T+A5)+
F 3*(B1*T 4+B2*T 3+B3*T 2+B4*T+B5)+
F 2*(C1*T 4+C2*T 3+C3*T 2+C4*T+C5)+
F*(D1*T 4+D2*T 3+D3*T 2+D4*T+D5)+
(E1*T 4+E2*T 3+E3*T 2+E4*T+E5)
Wherein, Y is the calculated value of said non-electrical quantities, and F is said frequency signal value, and T is said temperature signal value, and wherein, A1~A5, B1~B5, C1~C5, D1~D5 and E1~E5 are the coefficient of said high-order nonlinear secular equation.
In practical application, in order to improve the precision of detection, said high-order nonlinear secular equation can also increase the polynomial expression of the power of frequency F, for example, said high-order nonlinear secular equation can for
Y=F 5*(G1*T 4+G2*T 3+G3*T 2+G4*T+G5)+
F 4*(A1*T 4+A2*T 3+A3*T 2+A4*T+A5)+
F 3*(B1*T 4+B2*T 3+B3*T 2+B4*T+B5)+
F 2*(C1*T 4+C2*T 3+C3*T 2+C4*T+C5)+
F*(D1*T 4+D2*T 3+D3*T 2+D4*T+D5)+
(E1*T 4+E2*T 3+E3*T 2+E4*T+E5)
Wherein, Y is the calculated value of said non-electrical quantities, and F is said frequency signal value, and T is said temperature signal value, and wherein, A1~A5, B1~B5, C1~C5, D1~D5, E1~E5 and G1~G5 are the coefficient of said high-order nonlinear secular equation.
Utilize the high-order nonlinear fitting algorithm to calculate the coefficient of high-order nonlinear secular equation;
Gather unknown non-electrical quantities and convert said non-electrical quantities into the capacitance signal value, convert said capacitance signal value into the frequency signal value again, the collecting temperature signal value.
Said temperature signal value and the substitution of frequency signal value have been confirmed the said high-order nonlinear secular equation of coefficient and calculated the value of said non-electrical quantities.
Preferably; In this method, a plurality of known non-electrical quantities of said collection, a plurality of temperature signal value and a plurality of frequency signal value that is converted through capacitance signal by said known non-electrical quantities are to gather to be not less than 100,000 known non-electrical quantities, to be not less than 100,000 temperature signal value and to be not less than 100,000 frequency signal values that converted through capacitance signal by said known non-electrical quantities.
Preferably, in this method, the process of a plurality of temperature signal value of said collection comprises: change environment temperature according to preset rule, gather the temperature signal value under the varying environment temperature respectively.Concrete, said preset rule was kept this temperature two hours for environment temperature is slowly changed to subzero 40 ℃ from room temperature after subzero 40 ℃, be warmed up to 85 ℃ then, after 85 ℃, kept this temperature two hours, cooled to room temperature then.
Preferably, in this method, said a plurality of known non-electrical quantities numerically evenly distribute; Said a plurality of temperature signal value was evenly distributed on the time of gathering.
Preferably, in this method, said a plurality of known non-electrical quantities are integer; Said a plurality of temperature signal value is an integer.
To the above-mentioned explanation of the disclosed embodiments, make this area professional and technical personnel can realize or use the present invention.Multiple modification to these embodiment will be conspicuous concerning those skilled in the art, and defined General Principle can realize under the situation that does not break away from the spirit or scope of the present invention in other embodiments among this paper.Therefore, the present invention will can not be restricted to these embodiment shown in this paper, but will meet and principle disclosed herein and features of novelty the wideest corresponding to scope.

Claims (5)

1. a non-electrical quantities assay method is characterized in that, comprising:
Gather the value of a plurality of known non-electrical quantities, a plurality of temperature signal value and a plurality of frequency signal value that converts through capacitance signal by said known non-electrical quantities;
The high-order nonlinear secular equation that the value of said a plurality of known non-electrical quantities, said a plurality of temperature signal value and said a plurality of frequency signal value input that is converted through capacitance signal by said known non-electrical quantities is contained undetermined coefficient
Y=F 4*(A1*T 4+A2*T 3+A3*T 2+A4*T+A5)+
F 3*(B1*T 4+B2*T 3+B3*T 2+B4*T+B5)+
F 2*(C1*T 4+C2*T 3+C3*T 2+C4*T+C5)+
F*(D1*T 4+D2*T 3+D3*T 2+D4*T+D5)+
(E1*T 4+E2*T 3+E3*T 2+E4*T+E5)
And utilize the high-order nonlinear fitting algorithm to calculate the undetermined coefficient of said high-order nonlinear secular equation; Wherein, Y is the calculated value of non-electrical quantities, and F is said frequency signal value, and T is said temperature signal value; A1 ~ A5, B1 ~ B5, C1 ~ C5, D1 ~ D5 and E1 ~ E5 are the undetermined coefficient of said high-order nonlinear secular equation, the relation equation of the value that said high-order nonlinear secular equation is said non-electrical quantities, said temperature signal value and said frequency signal value;
Gather unknown non-electrical quantities and convert the non-electrical quantities of said the unknown into the capacitance signal value, will convert the frequency signal value into by the capacitance signal value that the non-electrical quantities of said the unknown is converted to, the collecting temperature signal value again;
Confirmed the said high-order nonlinear secular equation of coefficient and calculated the value of the non-electrical quantities of said the unknown with the said temperature signal value of gathering with by the frequency signal value substitution that the non-electrical quantities of said the unknown is converted to.
2. method according to claim 1; It is characterized in that a plurality of known non-electrical quantities of said collection, a plurality of temperature signal value and a plurality of frequency signal value that is converted through capacitance signal by said known non-electrical quantities are to gather to be not less than 100,000 known non-electrical quantities, to be not less than 100,000 temperature signal value and to be not less than 100,000 frequency signal values that converted through capacitance signal by said known non-electrical quantities.
3. method according to claim 1 and 2 is characterized in that, the process of a plurality of temperature signal value of said collection comprises:
Change environment temperature according to preset rule, gather the temperature signal value under the varying environment temperature respectively.
4. method according to claim 1 is characterized in that, said a plurality of known non-electrical quantities numerically evenly distribute; Said a plurality of temperature signal value was evenly distributed on the time of gathering.
5. method according to claim 1 is characterized in that, said a plurality of known non-electrical quantities are integer; Said a plurality of temperature signal value is an integer.
CN2010102430966A 2010-08-02 2010-08-02 Non-electric quantity determination system and method Expired - Fee Related CN101936746B (en)

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CN102610996B (en) * 2012-01-19 2014-05-14 厦门优迅高速芯片有限公司 Method and device for rapidly calibrating luminous power
CN114841099B (en) * 2022-07-04 2022-10-11 浙江铖昌科技股份有限公司 Method, device, equipment and system for constructing characterization model

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