CN102510284B - Methods and devices for calibrating alternating-current voltage signal and alternating current signal - Google Patents

Abstract

The invention provides methods and devices for calibrating an alternating-current voltage signal and an alternating current signal. The method for calibrating the alternating-current voltage signal comprises the following steps of: firstly, taking an average value of N-point sampling data within a last sampling period as a zero-point parameter of the current sampling period; secondly, carrying out zero-point correction on the sampling data according to the zero-point parameter; thirdly, respectively calculating an effective value of the voltage according to the sampling data subjected to the zero-point correction; fourthly, receiving standard data of the voltage; fifthly, calculating an amplitude parameter of the voltage according to the standard data and the effective value of the voltage; and sixthly, correcting the calculated effective value of the voltage by using the amplitude parameter to obtain an original data value of the sampling signal. According to the methods provided by the invention, the design cost is greatly reduced and a design circuit is simplified; and the difference between the precision of an integrated circuit and the precision of an electronic element is eliminated, so that the reliability of hardware is increased, the time required for calibrating the parameters in the batch-production process is shortened, human errors introduced into the calibration are greatly reduced and the accuracy of the sampling data is increased.

Description

The calibration steps of a kind of ac voltage signal and ac current signal and device thereof

Technical field

The present invention relates to the calibration steps of a kind of ac voltage signal and ac current signal.

Background technology

Voltage in AC system or current sample, first through signal transducer, will be converted to ac small signal, then deliver to microprocessor by modulate circuit and carry out analog-to-digital conversion, and data sampling and process, obtain target data.In prior art, be converted in the process of target data at voltage signal or electric current AC signal, in order to obtain target data more accurately, use high-precision electronic device (such as precision resister, high-operational amplifier) and adjustable device (adjustable accurate resistance, adjustable condenser).Because these devices are adjustment in use instrument manual adjustments, and only allow to regulate once before dispatching from the factory, can not regulate again after dispatching from the factory, like this, not only add hardware cost, and easily introduce human error in test process, reduce reliability.

Summary of the invention

Technical problem to be solved by this invention is to provide the calibration steps of a kind of ac voltage signal and ac current signal, does not need to use high-precision electronic device and adjustable device can solve the calibration Problems existing of above-mentioned AC signal.

In order to solve the problems of the technologies described above, the invention provides a kind of ac voltage signal calibration steps: comprise the steps:

Step 1, using the zero point parameter of the mean value of N point sampling data in the up-sampling cycle as this sampling period;

Step 2, according to parameter at above-mentioned zero point, correction at zero point is carried out to sampled data;

Step 3, according to revised sampled data at zero point calculating voltage effective value respectively;

Step 4, receiver voltage normal data;

Step 5, magnitude parameters according to voltage standard data and voltage effective value calculating voltage;

Step 6, use magnitude parameters are revised the voltage effective value after calculating, obtain the data value of the high-voltage AC signal inputted.

Further, also comprise the steps:

Input ac voltage signal, changes into ac small signal by alternating voltage circulation;

Adjustment ac voltage signal, changes into ac high-voltage signal and the voltage analog signal of voltage analog signal to input of Direct Sampling can get N number of sampled point sample in one-period;

Further, step 4 also comprises reception calibration command.

Further, the step of the magnitude parameters of storage voltage is also comprised.

Meanwhile, the present invention also provides a kind of ac voltage signal calibrating installation, comprising:

Zero point parameter extraction module, for using the zero point parameter of the mean value of N point sampling data in the up-sampling cycle as this sampling period;

Data correcting module at zero point, carry out revising voltage effective value computing module zero point, according to revised sampled data at zero point calculating voltage effective value respectively to sampled data according to parameter at above-mentioned zero point

Receiver module, receiver voltage normal data

Magnitude parameters computing module, magnitude parameters according to voltage standard data and voltage effective value calculating voltage;

Data correction module, use magnitude parameters are revised the voltage effective value after calculating, are the raw value of sampled signal.

Further, also comprise:

Voltage sensor, for changing into AC low-tension signal by ac high-voltage signal;

Signal conditioning circuit, for adjusting ac voltage signal, being changed into by ac high-voltage signal can the voltage analog signal of Direct Sampling;

Sample circuit, the voltage analog signal of input is got N number of sampled point and sampled in one-period;

Further, alternating voltage calibrating installation also comprises:

The magnitude parameters of memory module, storage voltage.

Meanwhile, the present invention also provides a kind of calibration method for AC current, it is characterized in that, comprises the steps:

Step 1, using the zero point parameter of the mean value of N point sampling data in the up-sampling cycle as this sampling period;

Step 2, according to parameter at above-mentioned zero point, correction at zero point is carried out to sampled data;

Step 3, according to revised sampled data at zero point calculating current effective value respectively;

Step 4, received current normal data;

Step 5, magnitude parameters according to current standard data and current effective value calculating current;

Step 6, use magnitude parameters are revised the three-phase current effective value after calculating, are the raw value of sampled signal.

Further, also comprise the steps: before step 1

Input AC current signal, changes into AC great current signal and exchanges small area analysis signal;

Adjustment ac current signal, changing into can the voltage analog signal of Direct Sampling;

In one-period, get N number of sampled point to the current analog signal of input to sample;

Further, after step 6, also comprise the step of the magnitude parameters of storaging current.

Meanwhile, the present invention also provides a kind of calibrating installation of alternating current, comprises

Zero point parameter extraction module, for using the zero point parameter of the mean value of N point sampling data in the up-sampling cycle as this sampling period;

Data correcting module at zero point, according to parameter at above-mentioned zero point, correction at zero point is carried out to sampled data;

Current effective value computing module, according to revised sampled data at zero point calculating current effective value respectively

Receiver module, received current normal data

Magnitude parameters computing module, magnitude parameters according to current standard data and current effective value calculating current;

Data correction module, use magnitude parameters are revised the current effective value after calculating, are the raw value of sampled signal.

Further, the calibrating installation of alternating current of the present invention, also comprises:

Current sensor, for changing into alternating current small-signal by ac current signal;

Signal conditioning circuit, for adjusting ac current signal, being changed into by ac current signal can the voltage analog signal of Direct Sampling;

Sample circuit, the voltage analog signal of input is got N number of sampled point and sampled in one-period;

Further, the calibrating installation of alternating current of the present invention, is characterized in that, also comprises: the magnitude parameters of memory module, storaging current.

Adopt alternating voltage calibration steps of the present invention and calibration method for AC current, design cost will be greatly reduced, simplify design circuit, overcome the difference of integrated circuit and electronic component precision, improve hardware reliability, shorten the time in batch production process required for parametric calibration, greatly reduce the human error introduced in calibration, improve the accuracy of sampled data.

Accompanying drawing explanation

Fig. 1 is alternating voltage calibrating principle block diagram

Fig. 2 is alternating voltage calibration software flow chart

Fig. 3 is alternating current calibrating principle figure

Fig. 4 is alternating current calibration software flow chart

Embodiment

In order to make object of the present invention, technical scheme and advantage more clear, below in conjunction with drawings and Examples, set forth the present invention further, instantiation described herein only in order to explain the present invention, is not intended to limit the present invention.

The alternating voltage calibrating principle block diagram of composition graphs 1 illustrates that the calibration steps of ac voltage signal of the present invention comprises the steps:

1, input ac voltage signal, changes into AC low-tension signal by ac high-voltage signal;

2, adjust ac voltage signal, being changed into by AC low-tension signal can the voltage analog signal of Direct Sampling

3, in one-period, get N number of sampled point to the voltage analog signal of input to sample;

4, using the zero point parameter of the mean value of N point sampling data in the up-sampling cycle as the next sampling period;

5, according to parameter at above-mentioned zero point, correction at zero point is carried out to sampled data; Revise sampling limit, limit zero point to revise, need to revise each sampled point use parameter at same zero point.

6, the voltage effective value of three-phase is calculated respectively according to revised sampled data at zero point

7, microprocessor receiver voltage normal data and calibration command

8, the magnitude parameters of three-phase voltage is calculated according to voltage standard data and voltage effective value

9, use magnitude parameters to revise the voltage effective value after calculating, obtain the data value of the high-voltage AC signal inputted.

10, store the magnitude parameters of three-phase voltage, do not store the parameter at zero point of three-phase voltage.

Similarly, the calibrating installation of ac voltage signal of the present invention comprises:

Voltage sensor, for changing into low AC voltage signal by ac high voltage signal;

Signal conditioning circuit, for adjusting ac voltage signal, being changed into by ac high-voltage signal can the voltage analog signal of Direct Sampling, and it comprises: the current potential comprising superposition DC component promotes circuit, amplifying circuit, filter circuit and clamp circuit, and microprocessor carries AD sample port.Because signal conditioning circuit is prior art, do not repeat them here.

Sample circuit, the three-phase voltage analog signal of input to be sampled respectively N point in one-period;

Every phase parameter extraction module at zero point, for using the zero point parameter of the mean value of phase N point sampling data every in the up-sampling cycle as the next sampling period;

Data correcting module at zero point, for carrying out correction at zero point according to parameter at above-mentioned zero point to sampled data; Revise sampling limit, limit zero point to revise, need to revise each sampled point use parameter at same zero point of every phase.

Voltage effective value computing module, calculate the voltage effective value of three-phase respectively according to revised sampled data at zero point;

Receiver module, for receiver voltage normal data and calibration command;

Magnitude parameters computing module, calculate the magnitude parameters of three-phase voltage according to voltage standard data and voltage effective value;

Data correction module, uses magnitude parameters to revise the voltage effective value after calculating, is the raw value of sampled signal.

The magnitude parameters of memory module, storage three-phase voltage, and do not store the parameter at zero point of three-phase voltage.

The alternating voltage calibration software flow chart of composition graphs 2 carefully illustrates specific works of the present invention and computational process:

Microprocessor carries out discrete sampling to the three-phase voltage analog signal directly entering AD sample port in one-period, each sampling period is N number of sampled point, the sample numerical value obtained in one-period leaves DVa [N] in, DVb [N], DVc [N], zero point is DVa [N]-ZVa after revising, DVb [N]-ZVb, DVc [N]-ZVc, use revised data DVa [N]-ZVa at zero point, DVb [N]-ZVb, DVc [N]-ZVc calculates A, B, the voltage effective value Va of C three-phase, Vb, Vc, wherein calculate A, B, C three-phase voltage effective value uses root mean square calculation formula, computational process is as follows:

$\mathrm{Va}=\sqrt{\frac{\underset{i=0}{\overset{N-1}{\mathrm{\Σ}}}\left(\mathrm{DVa}\right[i]-\mathrm{ZVa})*\left(\mathrm{DVa}\right[i]-\mathrm{ZVa})}{N}}$

$\mathrm{Vb}=\sqrt{\frac{\underset{i=0}{\overset{N-1}{\mathrm{\Σ}}}\left(\mathrm{DVb}\right[i]-\mathrm{ZVb})*\left(\mathrm{DVb}\right[i]-\mathrm{ZVb})}{N}}$

$\mathrm{Vc}=\sqrt{\frac{\underset{i=0}{\overset{N-1}{\mathrm{\Σ}}}\left(\mathrm{DVc}\right[i]-\mathrm{ZVc})*\left(\mathrm{DVc}\right[i]-\mathrm{ZVc})}{N}})$

Data DVa [N], DVb [N] after use discrete sampling, DVc [N] calculate the zero point parameter ZVa1 of mean value as the next sampling period of three-phase voltage data N point sampling data within this sampling period respectively, ZVb1, ZVc1.Zero point parameter computing formula, computational process is as follows: $\mathrm{ZVa}1=\frac{\underset{i=0}{\overset{N-1}{\mathrm{\Σ}}}\mathrm{DVa}\left[i\right]}{N};$ $\mathrm{ZVb}1=\frac{\underset{i=0}{\overset{N-1}{\mathrm{\Σ}}}\mathrm{DVb}\left[i\right]}{N};$ $\mathrm{ZVc}1=\frac{\underset{i=0}{\overset{N-1}{\mathrm{\Σ}}}\mathrm{DVc}\left[i\right]}{N}$ Microprocessor receives calibration A, B, C three-phase standard voltage data Vstd_a, after Vstd_b, Vstd_c and calibration command, the magnitude parameters that microprocessor calculates A, B, C three-phase voltage is respectively respectively KVa=Vstd_a/Va, KVb=Vstd_b/Vb, KVc=Vstd_c/Vc.Use magnitude parameters to compensate for the error problem bringing scale amplifying in signal condition process, the voltage data after using calibration parameter to calculate is Ua=Va*KVa; Ub=Vb*KVb; Uc=Vc*KVc, the Va wherein in this formula, Vb, Vc are a calculated after the sampled data of current sample period carries out correction at zero point, the effective value data of b, c three-phase voltage.KVa, KVb, KVc are a of the last calibration, the magnitude parameters of b, c three-phase voltage.Ua, Ub, Uc are for having carried out correction at zero point, and effective value calculates, a after amplitude correction, the end product of b, c three-phase voltage.Finally, the magnitude parameters of three-phase voltage is stored.This calibration steps adopts two-point method, is some parameter at zero point, and another point is magnitude parameters, only needs to store magnitude parameters in the non volatile power-down memory of main control unit after calibration terminates.

The alternating current calibrating principle block diagram of composition graphs 3 illustrates the calibration steps of ac current signal of the present invention:

1, input AC current signal, changes into Small Current Signal by AC great current signal;

2, adjust ac current signal, changing into can the voltage analog signal of Direct Sampling;

3, the current analog signal of input is sampled N point in one-period;

4, using the zero point parameter of the mean value of N point sampling data in the up-sampling cycle as the next sampling period;

5, according to parameter at above-mentioned zero point, correction at zero point is carried out to sampled data; Revise sampling limit, limit zero point to revise, need to revise each sampled point use parameter at same zero point in this cycle.

6, according to revised sampled data at zero point calculating current effective value respectively

7, microprocessor received current normal data and calibration command

8, according to the magnitude parameters of current standard data and current effective value calculating current

9, use magnitude parameters to revise the current effective value after calculating, be the raw value of sampled signal.

10, the magnitude parameters of storaging current.

Similarly, the calibrating installation of ac current signal of the present invention comprises:

Current sensor, exchanges small area analysis signal for being changed into by AC great current signal;

Signal conditioning circuit, for adjusting ac current signal, being changed into by ac current signal can the voltage analog signal of Direct Sampling, it comprises: the change-over circuit of electric current to voltage, the current potential lifting circuit of superposition DC component, amplifying circuit, filter circuit and clamp circuit, and microprocessor carries AD sample port.Because signal conditioning circuit is prior art, do not repeat them here.

Sample circuit, the three-phase current analog signal of input is got N number of sampled point and sampled in one-period;

Zero point parameter extraction module, for using the zero point parameter of the mean value of N point sampling data in the up-sampling cycle as the next sampling period;

Data correcting module at zero point, for carrying out correction at zero point according to parameter at above-mentioned zero point to sampled data; Revise sampling limit, limit zero point to revise, need to revise each sampled point use parameter at same zero point;

Current effective value computing module, according to revised sampled data calculating current effective value at zero point;

Receiver module, for received current normal data and calibration command;

Magnitude parameters computing module, magnitude parameters according to current standard data and current effective value calculating current;

Data correction module, uses magnitude parameters to revise the current effective value after calculating, is the raw value of sampled signal;

The magnitude parameters of memory module, storage three-phase current.

The alternating current calibration software flow chart of composition graphs 4 carefully illustrates specific works of the present invention and computational process, for the calibration steps of a phase current in this specific embodiment.

Microprocessor carries out discrete sampling to the alternating current analog signal directly entering AD sample port in one-period, each sampling period is N number of sampled point numerical value sum, the sample numerical value obtained in one-period leaves DIa [N] (in addition for a phase so that the calibration process of electric current to be described) in, zero point is DIa [N]-ZIa after revising, use revised data DIa [N]-ZIa at zero point calculates alternating current effective value Ia in this sampling period, and the formula calculating Ia is: $\mathrm{Ia}=\sqrt{\frac{\underset{i=0}{\overset{N-1}{\mathrm{\Σ}}}\left(\mathrm{DIa}\right[i]-\mathrm{ZIa})*\left(\mathrm{DIa}\right[i]-\mathrm{ZIa})}{N}}$ Data DIa [N] calculating mean value after use discrete sampling is as the parameter ZIa1 at zero point in next sampling period, and the computing formula calculating parameter at zero point is: $\mathrm{ZIa}1=\frac{\underset{i=0}{\overset{N-1}{\mathrm{\Σ}}}\mathrm{DIa}\left[i\right]}{N},$ In order to not affect the computational speed of this cycle data, the sampled value in this cycle of parameters revision at zero point using the previous sampling period to calculate.After microprocessor receives normalized current data Istd_a and calibration command, the magnitude parameters that microprocessor calculates alternating current is KIa=Istd_a/Ia, and compensate for the problem bringing scale amplifying in signal condition process, is second point parameter.Current data after using calibration parameter to calculate is Ia '=Ia*KIa; The a phase current effective value data calculated after the sampled data of the Ia current sample period wherein in this formula carries out correction at zero point.KIa is the magnitude parameters of a phase current of the last calibration.Ia ' is for having carried out correction at zero point, and effective value calculates, the end product of the electric current after amplitude correction.Be more than for a phase current, the calibration steps of b, c phase current is consistent with a phase current, is not repeating at this.This calibration steps adopts two-point method, is some parameter at zero point, and another point is magnitude parameters, only needs to store magnitude parameters in the non volatile power-down memory of main control unit after calibration terminates.

In alternating-current system the AC three-phase voltage input signal of main control unit and branching unit, alternating current input signal all employ calibration steps of the present invention.

At AC power distribution cabinet/AC distribution panel, the alternating voltage in interchange output counter system and ac current signal all can use calibration Fang Fafa of the present invention.

Software calibration is carried out respectively at basic Shang Duimou road ac voltage signal of the present invention and ac current signal, the voltage calibration parameter calculated and correcting current parameter, can be used for the active power revising this road signal, reactive power, the data such as active electrical degree, idle electric degree.And the amplitude correction parameter of power and electric degree upgrades automatically along with the calibration parameter of voltage and current, do not need to store in the nonvolatile memory.

The above is only the preferred embodiment of the present invention, it should be pointed out that the engineer of any the art, and under the premise of not departing from the present invention, also may carry out improvements and modifications, these improvements and modifications are all considered as protection scope of the present invention.

Claims (17)

1. a calibration steps for ac voltage signal, is characterized in that, comprises the steps:

Step 1, using the zero point parameter of the mean value of N point sampling data in the up-sampling cycle as this sampling period;

Step 2, according to parameter at above-mentioned zero point, correction at zero point is carried out to sampled data;

Step 3, according to revised sampled data and root mean square calculation formula respectively calculating voltage effective value at zero point;

Step 4, receiver voltage normal data;

Step 5, magnitude parameters according to voltage standard data and voltage effective value calculating voltage;

Step 6, use magnitude parameters are revised the voltage effective value after calculating, obtain the data value of the high-voltage AC signal inputted.

2. the calibration steps of ac voltage signal according to claim 1, is characterized in that, also comprises the steps: before step 1

Input ac voltage signal, changes into ac small signal by alternating voltage;

Adjustment ac voltage signal, being changed into by ac high-voltage signal can the voltage analog signal of Direct Sampling;

In one-period, get N number of sampled point to the voltage analog signal of input to sample.

3. the calibration steps of ac voltage signal according to claim 1, is characterized in that, also comprises after step 6, the step of the magnitude parameters of storage voltage.

4. the calibration steps of ac voltage signal according to claim 1, is characterized in that, the computational methods of described voltage effective value are:

$V=\sqrt{\frac{\underset{i=0}{\overset{N-1}{\mathrm{\Σ}}}\left(\mathrm{DV}\right[i]-\mathrm{ZV})*\left(\mathrm{DV}\right[i]-\mathrm{ZV})}{N}}$

Wherein, V is the effective value of voltage, and ZV is parameter at zero point, and DV [N]-ZV is revised sampled data at zero point.

5. the calibration steps of ac voltage signal according to claim 4, is characterized in that, the computational methods of described magnitude parameters are: KV=Vstd/V, and wherein KV is magnitude parameters, and Vstd is standard voltage data, and V is the effective value of voltage.

6. the calibration steps of ac voltage signal according to claim 4, is characterized in that, revised voltage effective value is respectively: U=V*KV, and wherein, V is the effective value of voltage, and KV is the magnitude parameters of the voltage of the last calibration.

7. an ac voltage signal calibrating installation, is characterized in that, comprising:

Zero point parameter extraction module, for using the zero point parameter of the mean value of N point sampling data in the up-sampling cycle as this sampling period;

Data correcting module at zero point, according to parameter at above-mentioned zero point, correction at zero point is carried out to sampled data;

Voltage effective value computing module, according to revised sampled data calculating voltage effective value at zero point;

Receiver module, receiver voltage normal data;

Magnitude parameters computing module, magnitude parameters according to voltage standard data and voltage effective value calculating voltage;

Data correction module, use magnitude parameters are revised the voltage effective value after calculating, obtain the data value of the high-voltage AC signal inputted.

8. a kind of ac voltage signal calibrating installation according to claim 7, is characterized in that, also comprise:

Voltage transformation module, for changing into AC low-tension signal by ac high voltage signal;

Signal-regulated kinase, for adjusting ac voltage signal, being changed into by ac high-voltage signal can the voltage analog signal of Direct Sampling;

Sampling module, samples for getting N number of sampled point to the voltage analog signal of input in one-period.

9. a calibration method for AC current, is characterized in that, comprises the steps:

Step 1, using the zero point parameter of the mean value of N point sampling data in the up-sampling cycle as this sampling period;

Step 2, according to parameter at above-mentioned zero point, correction at zero point is carried out to sampled data;

Step 3, according to revised sampled data and root mean square calculation formulae discovery current effective value at zero point;

Step 4, received current normal data;

Step 5, magnitude parameters according to current standard data and current effective value calculating current;

Step 6, use magnitude parameters are revised the current effective value after calculating, obtain the data value of the high-voltage AC signal inputted.

10. calibration method for AC current according to claim 9, is characterized in that, also comprises the steps: before step 1

Input AC current signal, changes into ac small signal by ac current signal;

Adjustment ac current signal, changing into can the voltage analog signal of Direct Sampling;

In one-period, get N number of sampled point to the current analog signal of input to sample.

11. calibration method for AC currents according to claim 10, is characterized in that, described step 4 also comprises the step receiving calibration command.

12. calibration method for AC currents according to claim 11, is characterized in that, also comprise the step of the magnitude parameters of storaging current after step 6.

13. calibration method for AC currents according to claim 9, is characterized in that, the computational methods of current effective value are:

$I=\sqrt{\frac{\underset{i=0}{\overset{N-1}{\mathrm{\Σ}}}\left(\mathrm{DI}\right[i]-\mathrm{ZI})*\left(\mathrm{DI}\right[i]-\mathrm{ZI})}{N}}$

Wherein, ZI is corrected parameter at zero point, and DI [N]-ZI is revised sampled data at zero point.

14. calibration method for AC currents according to claim 13, is characterized in that: current amplitude parameter be KI=Istd/I wherein Istd be normalized current data, I is current effective value.

15. calibration method for AC currents according to claim 14, is characterized in that, revised current data is I '=I*KI; Wherein, I is current effective value, and KI is the magnitude parameters changing electric current into of the last calibration.

The calibrating installation of 16. 1 kinds of alternating currents, is characterized in that, comprising:

Zero point parameter extraction module, for using the zero point parameter of the mean value of N point sampling data in the up-sampling cycle as this sampling period;

Data correcting module at zero point, according to parameter at above-mentioned zero point, correction at zero point is carried out to sampled data;

Current effective value computing module, according to revised sampled data at zero point calculating current effective value respectively;

Receiver module, received current normal data;

Magnitude parameters computing module, magnitude parameters according to current standard data and current effective value calculating current;

Data correction module, use magnitude parameters are revised the current effective value after calculating, obtain the data value of input current.

The calibrating installation of 17. alternating currents according to claim 16, is characterized in that, also comprise:

Current conversion module, for changing into alternating voltage small-signal by ac current signal;

Signal-regulated kinase, for adjusting ac voltage signal, being changed into by AC great current signal can the voltage analog signal of Direct Sampling;

Sampling module, samples for getting N number of sampled point to the voltage analog signal of input in one-period.