CN202261036U - Zero drift digital suppression device for actual value sampling of alternating current-alternating current frequency converter - Google Patents
Zero drift digital suppression device for actual value sampling of alternating current-alternating current frequency converter Download PDFInfo
- Publication number
- CN202261036U CN202261036U CN2011203201432U CN201120320143U CN202261036U CN 202261036 U CN202261036 U CN 202261036U CN 2011203201432 U CN2011203201432 U CN 2011203201432U CN 201120320143 U CN201120320143 U CN 201120320143U CN 202261036 U CN202261036 U CN 202261036U
- Authority
- CN
- China
- Prior art keywords
- input
- output
- frequency converter
- alternating current
- subtracter
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Landscapes
- Analogue/Digital Conversion (AREA)
Abstract
The utility model discloses a zero drift digital suppression device for the actual value sampling of an alternating current-alternating current frequency converter, relates to the technical field of data sampling and aims to solve the technical problems of complex structure, inconvenience for debugging, low accuracy, low reliability and high cost of the conventional device. The device comprises the alternating current-alternating current frequency converter, an alternating current-alternating current frequency converter sampling device, a selector switch, an integrating device, a subtracter, an analogue/digital (A/D) converter and a controller, wherein the sampling end of the alternating current-alternating current frequency converter sampling device is connected with the alternating current-alternating current frequency converter; the common input end of the selector switch is connected with the output end of the alternating current-alternating current frequency converter sampling device; one selector output end of the selector switch is connected with the first input end of the subtracter, and the other selector output end of the selector switch is connected with the second input end of the subtracter through the integrating device; and the analogue input end of the A/D converter is connected with the output end of the subtracter, and a data output interface and each control signal input end of the A/D converter are connected to the controller. The device is applied to both the alternating current-alternating current frequency converter and an alternating current-direct current-alternating current frequency converter.
Description
Technical field
The utility model relates to the data sampling technology, particularly relates to a kind of technology of null offset numeral restraining device of AC-AC frequency converter actual value sampling.
Background technology
Accurate sampled value is the necessary condition of the good operation of high-performance AC-AC frequency converter.Existing braking measure to null offset in the image data except selected element, element is carried out burin-in process, selects high stability power supply for use and with the method for stablizing quiescent point, often in side circuit is adopted compensation and is modulated two kinds of methods.
Penalty method is meant the drift of offsetting amplifying circuit with the drift of another one components and parts, if parameter ties in, just can be suppressed at drift within the lower limit.Can be divided into the hardware circuit compensation and in intelligent chip or microcomputer, realize compensation according to the condition of reality with software approach.But proofread and correct with hardware circuit mostly have complicated circuit, debug difficulties, shortcomings such as precision is low, versatility is poor, cost height, be unfavorable for the engineering practical application.And software approach is that microcomputer and data acquisition system are connect, though the effect of software compensation is better than hardware compensating, but is still having weak point aspect versatility and the debugging.
Modulation method is meant the variable quantity (like the variation of sinusoidal wave amplitude) that the direct current variable quantity is converted into other form, and amplify through the very little resaistance-capacity coupling circuit of drift, manages the signal that has amplified is reduced to the variation of direct current composition again.This mode circuit structure is complicated, cost is high, frequency characteristic is poor.
The utility model content
To the defective that exists in the above-mentioned prior art, the utility model technical problem to be solved provides the null offset numeral restraining device of the low AC-AC frequency converter actual value sampling of a kind of debugging simple in structure, easy, precision height, good reliability and cost.
In order to solve the problems of the technologies described above; The null offset numeral restraining device of a kind of AC-AC frequency converter actual value sampling that the utility model provided; Comprise AC-AC frequency converter and AC-AC frequency converter sampling apparatus, it is characterized in that: also comprise selector switch, integrating gear, subtracter, A/D converter and controller;
Said AC-AC frequency converter sampling apparatus is provided with a sampling end, an output, and its sampling end connects AC-AC frequency converter;
Said subtracter is provided with two inputs, an output, and its two inputs are respectively first input end, second input;
Said selector switch has a public input, two selection outputs; The output of its public input termination AC-AC frequency converter sampling apparatus; The first input end of an one of which selection output termination subtracter, another selects output to receive second input of subtracter through integrating gear;
Said controller is provided with Data Input Interface and a plurality of control signal output ends; Said A/D converter is provided with analog quantity input, data output interface and a plurality of signal input end; The output of its analog quantity input termination subtracter; Its data output interface connects the Data Input Interface of controller, and its each signal input end is received each control signal output ends of controller respectively.
Further, said integrating gear comprises an integrator, a voltage retainer, and said subtracter, integrator and voltage retainer are operational amplifier, and the normal phase input end of said subtracter is a first input end, and inverting input is second input;
A first input end of selecting output warp one resistance to connect subtracter of said selector switch, another selects output to receive the inverting input of integrator through a resistance;
The normal phase input end of said integrator is received ground through a resistance, and its output is received its inverting input through an electric capacity, and receives the normal phase input end of voltage retainer through a resistance;
The normal phase input end of said voltage retainer is received ground through a resistance, and its output is received its inverting input, and receives second input of subtracter through a resistance;
The first input end of said subtracter is received ground through a resistance, and its output is received its second input.
Further, said controller is a singlechip chip, is provided with an interrupt signal input, and its each control signal output ends is respectively three addressing signal output parts, read signal output, write signal output, enable signal output;
Said A/D converter is provided with an EOC signal output part; Its each signal input end is respectively three bit address inputs, starting impulse input, address latch Enable Pin, data output enable end; Its EOC signal output part connects the interrupt signal input of controller, three addressing signal output parts of its three bit address input termination controller;
The read signal output of said controller and enable signal output warp one and door are received the data output enable end of A/D converter, and its write signal output and enable signal output are received the starting impulse input and the address latch Enable Pin of A/D converter through another and door.
The null offset numeral restraining device of the AC-AC frequency converter actual value sampling that the utility model provides; Adopt the very big integrating gear of time constant to realize the inhibition of null offset; Compared with prior art, have the advantages that the sampled value precision is high, operational reliability is strong, and simple in structure, debugging is convenient, cost is low; Be not only applicable to AC-AC frequency converter, be applicable to the ac-dc-ac inverter device yet.
Description of drawings
Fig. 1 is the structured flowchart of null offset numeral restraining device of the AC-AC frequency converter actual value sampling of the utility model embodiment;
Fig. 2 is the drift compensating circuit theory diagrams in the null offset numeral restraining device of AC-AC frequency converter actual value sampling of the utility model embodiment;
Fig. 3 is the control circuit schematic diagram of the controller control A/D conversion in the null offset numeral restraining device of AC-AC frequency converter actual value sampling of the utility model embodiment.
Embodiment
Embodiment to the utility model describes in further detail below in conjunction with description of drawings, but present embodiment is not limited to the utility model, and analog structure of every employing the utility model and similar variation thereof all should be listed the protection range of the utility model in.
As shown in Figure 1; The null offset numeral restraining device of a kind of AC-AC frequency converter actual value sampling that the utility model embodiment is provided; Comprise AC-AC frequency converter (not shown) and AC-AC frequency converter sampling apparatus U1, it is characterized in that: also comprise selector switch U2, integrating gear U3, subtracter U4, A/D converter U5 and controller U6;
Said AC-AC frequency converter sampling apparatus U1 is provided with a sampling end, an output, and its sampling end connects AC-AC frequency converter;
Said subtracter U4 is provided with two inputs, an output, and its two inputs are respectively first input end, second input;
Said selector switch U2 has a public input, two selection outputs; The output of its public input termination AC-AC frequency converter sampling apparatus U1; The first input end of an one of which selection output termination subtracter U4, another selects output to receive second input of subtracter U4 through integrating gear U3;
Said controller U6 is provided with Data Input Interface and a plurality of control signal output ends; Said A/D converter U5 is provided with analog quantity input, data output interface and a plurality of signal input end; The output of its analog quantity input termination subtracter U4; Its data output interface connects the Data Input Interface of controller U6, and its each signal input end is received each control signal output ends of controller U6 respectively.
Among the utility model embodiment, said AC-AC frequency converter sampling apparatus U1, selector switch U2 are prior art.
The utility model embodiment is following to the null offset numeral inhibition principle of AC-AC frequency converter actual value sampling:
AC-AC frequency converter sampling apparatus U1 samples to the AC-AC frequency converter actual value through its sampling end;
When AC-AC frequency converter is input as zero; Because of factors such as temperature or voltage instabilities; The actual sample value of AC-AC frequency converter sampling apparatus U1 and non-vanishing (promptly having null offset); The output valve of its output is also non-vanishing, and the sampled signal when be input as zero through selector switch U2 with AC-AC frequency converter this moment is sent into integrating gear U3, and integrating gear U3 carries out integration to the sampled signal of input; And the time constant of integrating gear is very big, and the new data that behind the integrating gear integration, obtains is required datum offset amount at zero point;
When AC-AC frequency converter is imported when non-vanishing; The actual sample value of AC-AC frequency converter sampling apparatus U1 contains drift value equally; Directly send in subtracter U4 through the sampled signal that selector switch U2 imports AC-AC frequency converter when non-vanishing this moment; The datum offset amount at zero point that obtains when being input as zero with AC-AC frequency converter subtracts; Can be eliminated the sampled value signal after the null offset accurately, this sampled value signal is sent in the controller after A/D converter U5 converts numerical data into, thus the AC-AC frequency converter actual value after the null offset value that is eliminated.
As shown in Figure 2; Among the utility model embodiment; Said integrating gear U3 comprises an integrator U3A, a voltage retainer U3B; Said subtracter U4, integrator U3A and voltage retainer U3B are operational amplifier, and the normal phase input end of said subtracter U4 is a first input end, and inverting input is second input;
Said subtracter U4, integrator U3A, voltage retainer U3B and selector switch U2 form a drift compensating circuit;
The public input (pin one) of said selector switch U2 connects the output of AC-AC frequency converter sampling apparatus U1 (not shown); One of which selection output (pin 3) warp one resistance R 22 connects the first input end of subtracter U4, and another selects output (pin two) to receive the inverting input of integrator U3A through a resistance R 0;
The normal phase input end of said integrator U3A is received ground through a resistance R 1, and its output is received its inverting input through a capacitor C, and receives the normal phase input end of voltage retainer U3B through a resistance R 3;
The normal phase input end of said voltage retainer U3B is received ground through a resistance R 4, and its output is received its inverting input, and receives second input of subtracter U4 through a resistance R 21;
The first input end of said subtracter U4 is received ground through a resistance R 23, and its output is received its second input.
When AC-AC frequency converter is input as zero; Its sampled signal is sent into integrator U3A and is carried out integration; Obtain the signal behind the integration, the output of integrator U3A inserts the earth behind resistance R 3 and R4, and the normal phase input end of voltage retainer U3B is datum offset amount at zero point from obtaining signal between two resistance R 3, the R4; This, datum offset amount exported subtracter U4 to behind voltage retainer U3B at zero point, and subtracter U4 does the sampled signal after subtraction promptly gets drift compensating to two groups of input signals of input.
As shown in Figure 3; Among the utility model embodiment; Said controller U6 is a singlechip chip; Be provided with an interrupt signal input INTERRUPT, its each control signal output ends is respectively three addressing signal output parts (AD0 to AD2), read signal output READ, write signal output WRITE, enable signal output terminals A DDRESS;
Said A/D converter U5 is provided with an EOC signal output part EOC; Its each signal input end is respectively three bit address inputs (pin A, B, C), starting impulse input START, address latch Enable Pin ALE, data output enable end OE; Its analog quantity input In0 connects the output of subtracter U4; Its data output interface (pin two-1 is to 2-8) connects the Data Input Interface (pin DB0 to DB7) of controller U6; Its EOC signal output part EOC meets the interrupt signal input INTERRUPT of controller U6, and its three bit address input (pin A, B, C) connects three addressing signal output parts (AD0 to AD2) of controller U6;
The read signal output READ of said controller U6 and enable signal output terminals A DDRESS receive the data output enable end OE of A/D converter U5 through one with door Y1, and its write signal output WRITE and enable signal output terminals A DDRESS receive starting impulse input START and the address latch Enable Pin ALE of A/D converter U5 through another with door Y2;
Said controller U6 is used to handle the sampled signal of eliminating after the null offset value; And, receive the sampled signal after the elimination null offset value that the data output interface (pin two-1 is to 2-8) of A/D converter U5 sends through its Data Input Interface (pin DB0 to DB7) through its interrupt signal input INTERRUPT and each control signal output ends control A/D converter U5 work.
Among the utility model embodiment, the model of said controller U6 is 89C51, and said A/D converter U5 is that model is the A/D conversion chip of ADC0808.
Claims (3)
1. the null offset numeral restraining device of an AC-AC frequency converter actual value sampling comprises AC-AC frequency converter and AC-AC frequency converter sampling apparatus, it is characterized in that: also comprise selector switch, integrating gear, subtracter, A/D converter and controller;
Said AC-AC frequency converter sampling apparatus is provided with a sampling end, an output, and its sampling end connects AC-AC frequency converter;
Said subtracter is provided with two inputs, an output, and its two inputs are respectively first input end, second input;
Said selector switch has a public input, two selection outputs; The output of its public input termination AC-AC frequency converter sampling apparatus; The first input end of an one of which selection output termination subtracter, another selects output to receive second input of subtracter through integrating gear;
Said controller is provided with Data Input Interface and a plurality of control signal output ends; Said A/D converter is provided with analog quantity input, data output interface and a plurality of signal input end; The output of its analog quantity input termination subtracter; Its data output interface connects the Data Input Interface of controller, and its each signal input end is received each control signal output ends of controller respectively.
2. the null offset numeral restraining device of AC-AC frequency converter actual value sampling according to claim 1; It is characterized in that: said integrating gear comprises an integrator, a voltage retainer; Said subtracter, integrator and voltage retainer are operational amplifier; The normal phase input end of said subtracter is a first input end, and inverting input is second input;
A first input end of selecting output warp one resistance to connect subtracter of said selector switch, another selects output to receive the inverting input of integrator through a resistance;
The normal phase input end of said integrator is received ground through a resistance, and its output is received its inverting input through an electric capacity, and receives the normal phase input end of voltage retainer through a resistance;
The normal phase input end of said voltage retainer is received ground through a resistance, and its output is received its inverting input, and receives second input of subtracter through a resistance;
The first input end of said subtracter is received ground through a resistance, and its output is received its second input.
3. the null offset numeral restraining device of AC-AC frequency converter actual value sampling according to claim 1; It is characterized in that: said controller is a singlechip chip; Be provided with an interrupt signal input; Its each control signal output ends is respectively three addressing signal output parts, read signal output, write signal output, enable signal output;
Said A/D converter is provided with an EOC signal output part; Its each signal input end is respectively three bit address inputs, starting impulse input, address latch Enable Pin, data output enable end; Its EOC signal output part connects the interrupt signal input of controller, three addressing signal output parts of its three bit address input termination controller;
The read signal output of said controller and enable signal output warp one and door are received the data output enable end of A/D converter, and its write signal output and enable signal output are received the starting impulse input and the address latch Enable Pin of A/D converter through another and door.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011203201432U CN202261036U (en) | 2011-08-30 | 2011-08-30 | Zero drift digital suppression device for actual value sampling of alternating current-alternating current frequency converter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011203201432U CN202261036U (en) | 2011-08-30 | 2011-08-30 | Zero drift digital suppression device for actual value sampling of alternating current-alternating current frequency converter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN202261036U true CN202261036U (en) | 2012-05-30 |
Family
ID=46122217
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2011203201432U Expired - Fee Related CN202261036U (en) | 2011-08-30 | 2011-08-30 | Zero drift digital suppression device for actual value sampling of alternating current-alternating current frequency converter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN202261036U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102332829A (en) * | 2011-08-30 | 2012-01-25 | 上海交通大学 | Zero drift digital suppression device for sampling practical value of AC-AC (Alternating-Current-Alternating-Current) frequency converter |
-
2011
- 2011-08-30 CN CN2011203201432U patent/CN202261036U/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102332829A (en) * | 2011-08-30 | 2012-01-25 | 上海交通大学 | Zero drift digital suppression device for sampling practical value of AC-AC (Alternating-Current-Alternating-Current) frequency converter |
| CN102332829B (en) * | 2011-08-30 | 2014-06-18 | 上海交通大学 | Zero drift digital suppression device for sampling practical value of AC-AC (Alternating-Current-Alternating-Current) frequency converter |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101839931B (en) | Alternating current signal measurement device, system and method | |
| CN103630748B (en) | A kind of device and method measured for micro-grid harmonic impedance | |
| CN204085729U (en) | A kind of high-precision platinum resistance temperature measurement mechanism | |
| CN102692883B (en) | An analog input circuit for engineering-machinery-dedicated controller | |
| CN102332829B (en) | Zero drift digital suppression device for sampling practical value of AC-AC (Alternating-Current-Alternating-Current) frequency converter | |
| CN102723921B (en) | Digital lock phase amplification implementation method and system based on field programmable gate array | |
| CN104122439B (en) | Electric energy meter capable of improving phase correction precision | |
| CN209356665U (en) | A kind of multifunctional electric energy meter on-spot tester | |
| CN203587134U (en) | Tester with detection function of various position sensor signals | |
| CN103023046B (en) | Based on the operating passing zero filtering reactive power compensator that dsp chip controls | |
| CN202261036U (en) | Zero drift digital suppression device for actual value sampling of alternating current-alternating current frequency converter | |
| CN103575976B (en) | A kind of pure 90 degree of phase shift reactive power measuring methods | |
| CN209894870U (en) | Conversion circuit for sampling output current of three-phase frequency converter | |
| CN204287388U (en) | A kind of bushing shell for transformer insulation state on-line monitoring device | |
| CN103176030B (en) | The harmonic detection method of distribution system | |
| CN203965533U (en) | A kind of individual line subscriber energy-saving potential and quality of power supply intelligent diagnosing instrument | |
| CN114371761B (en) | Self-calibration circuit and method for voltage swing of output signal of arbitrary waveform generator | |
| CN202548231U (en) | Detection device for substation merging unit | |
| CN204287312U (en) | A kind of three-phase voltage sample circuit | |
| CN205506934U (en) | Impact load electric energy measurement system | |
| CN103575975A (en) | Constant-90-degree phase shift type reactive power measurement circuit | |
| CN109030943B (en) | ATT 7022C-based voltage harmonic continuous measurement method | |
| CN102455239A (en) | Method utilizing phase-locking amplifier to detect weak signals of dynamic balancer and device for method | |
| CN104639053A (en) | High-precision weak signal amplification and measurement method | |
| CN201434890Y (en) | Multifunctional electric meter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20120530 Termination date: 20140830 |
|
| EXPY | Termination of patent right or utility model |