CN106321085A - Normalization method for induced polarization potential logging instrument - Google Patents

Abstract

The invention discloses a normalization method for an induced polarization potential logging instrument. According to the normalization method, an induced polarization potential normalization device and a normalization software module are involved; the induced polarization potential normalization device is composed of a signal source, a signal selection circuit, a reference electrode connector, a backflow electrode connector, an emitting electrode connector and a measuring electrode connector; and the backflow electrode connector and the reference electrode connector are connected with a backflow electrode and a reference electrode correspondingly, and the emitting electrode connector and the measuring electrode connector are connected with an emitting electrode and a measuring electrode of an array electrode system. 0VDC, +2.5VDC and +5VDC signals are generated by the signal source, and finally the normalization software module is used for conducting normalization processing and calculating on collected measurement data, so that gain and offset parameters of all electrodes are obtained. By means of the normalization method, the difference of responses of different measuring electrodes to same signals is eliminated, and therefore all channels have the same response when the instrument is used for measuring the same signals, and formation characteristics can be truly reflected.

Description

Induced polarization potential logging instrument method for normalizing

Technical field:

This invention relates to tool calibration method field, obtains all electrodes same defeated particular by experiment Enter the measurement data under signal conditioning, and use normalization algorithm that data are processed, it is thus achieved that each channel Compensating gain and offset parameter so that each channel of this instrument has on all four response to identical signal.

Prior art:

Induced polarization potential logging instrument at present, all takes array to measure electrode structure and carries out the polarization potential time Territory potential decay spectrometry, owing to Different electrodes measures the complete of the not possible design of circuit parameter of channel Unanimously, therefore when measuring identical signal, this species diversity of each electrode measurement channel circuit parameter can cause Between each electrode there is discordance in final measurement.And currently without calibrating or compensating this discordance Techniques or methods, this discordance can further result in measurement result distortion, and the measurement result of distortion can not The genuine property of reaction formation rock, can result in the deviation even mistake that later stage process is explained on the contrary.

Summary of the invention:

The purpose of this invention is respectively to measure for induced polarization potential logging instrument between channel to respond identical signal Variability issues, it is provided that a kind of induced polarization potential logging instrument normalization eliminating each interchannel response difference Method, eliminates the response difference between physical measurement channel, in order to obtain correct measurement result.

The technical scheme is that

Induced polarization potential logging instrument method for normalizing, the basis that the method is implemented includes: mainly by array electricity Polar system 11, electronic circuit 9, return electrode 10 and remote measurement short circuit connect into instrument string, and with ground system 8 Connect the induced polarization potential logging instrument of composition；Connected by signal source 1, signal selecting circuit 2, reference electrode Terminal 3, return electrode connect terminal 4, emission electrode connects terminal 5, measure electrode connecting end 6 composition Induced polarization current potential normalized device；And it is arranged on the normalization software module 7 three of ground system 8 Point.Wherein: return electrode connect terminal 4 and reference electrode connect terminal 3 respectively with return electrode 10 and ginseng Examine electrode 12 to be connected, emission electrode connect terminal 5 and measure electrode connecting end 6 respectively with array-electrode-series The emission electrode of 11 is connected with measuring electrode.The signal that emission electrode is sent by emission electrode connection terminal 5 is defeated Entering to signal source 1, return electrode connects terminal 4 provides earth signal input for signal source, and signal source 1 produces 0VDC ,+2.5VDC ,+5VDC signal, signal selecting circuit 2 selects corresponding signal as required, this letter Number by measure electrode connecting end 6 output to each measure electrode, reference electrode connect terminal 3 be instrument Device measuring circuit provides reference potential, and downhole instrument electronic circuit 9 and ground system 8 gather each measurement electrode Data, finally by normalization software module 7 to gather measurement data carry out according to meansigma methods normalization method Normalized and calculating, it is thus achieved that the gain of each electrode and offset parameter.

Described normalization computational methods are as follows:

Channel quantity is N, and the data that the most each channel collection obtains are M_i, i ∈ [1, N], by direct mean value method Can obtain:

Normalization formula is:

In formulaBe the average tried to achieve of 1 formula, i.e. value after normalization, M_iFor the data of channel each before normalization, GAIN_iAnd Offset_iIt is respectively gain and the offset parameter of respective channel；

Based on above-mentioned formula 1 and 2, at each channel, 0VDC, three signals of+2.5VDC ,+5VDC are adopted After having collected data, first select the data of 0VDC and+2.5VDC 2, after bringing into respectively in formula 2, each Channel all obtains a linear equation in two unknowns group, GAIN when obtaining low signal input range after calculating and The parameter value of OFFSET, then selects the data of+2.5VDC and+5VDC 2, repeats above-mentioned calculating process, Obtain GAIN and the OFFSET parameter value of high signal input range.

On the basis of the gain obtaining each electrode and offset parameter, produce gain further and side-play amount is returned One changes coordinate collection of illustrative plates.

Invention effect: the invention eliminates induced polarization potential logging instrument array-electrode-series different measuring electrode it Between difference that identical signal is responded so that this instrument has phase when measuring identical signal between each channel Same response, final induced polarization potential logging result can truly reflect formation characteristics.Gain profiles simultaneously Figure and side-play amount scattergram can also intuitively indicate the stability of channel and the abnormality of channel.

Accompanying drawing and the simple declaration of accompanying drawing

Fig. 1 is that induced polarization potential logging instrument method for normalizing implements schematic diagram；

Fig. 2 is gain distribution plots；

Fig. 3 is offset coordinates scattergram.

In figure: 1-signal source, 2-signal selecting circuit, 3-reference electrode connects terminal, and 4-return electrode is even Connecting terminal, 5-emission electrode connects terminal, and 6-measures electrode connecting end, 7-normalization software module, 8- Ground system, 9-electronic circuit, 10-return electrode, 11-array-electrode-series, 12-reference electrode.

Detailed description of the invention

As it is shown in figure 1, the induced polarization potential logging instrument that the method is implemented is mainly by array-electrode-series 11, electronics Circuit 9, return electrode 10 and remote measurement short circuit connect into instrument string and are connected to form with ground system 8.

This invention includes induced polarization current potential normalized device and normalization software module 7 two parts.Induced polarization Current potential normalized device is connected terminal 3, return electrode by signal source 1, signal selecting circuit 2, reference electrode Connect terminal 4, emission electrode connects terminal 5, measure electrode connecting end 6 composition, and wherein emission electrode is even The signal that emission electrode is sent by connecting terminal 5 is input to signal source, and it is signal source that return electrode connects terminal 4 Offer earth signal inputs, signal source 1 produce 0VDC ,+2.5VDC ,+5VDC signal, signal selecting circuit 2 select corresponding signal as required, and this signal is measured to each by measuring electrode connecting end 6 output Electrode, reference electrode connects terminal 3 provides reference potential for apparatus measures circuit, by downhole instrument electronics Circuit and ground system gather the data of each measurement electrode, finally by normalization software module 7 to normalization The measurement data gathered in journey is normalized according to meansigma methods normalization method and calculates, it is thus achieved that Mei Ge electricity The gain of pole and side-play amount, and produce gain and side-play amount normalization coordinate collection of illustrative plates.

In implementation process, the return electrode of induced polarization current potential normalized device is connected terminal 4, reference electrode Connect terminal 3, emission electrode connect terminal 5, measure electrode connecting end 6 respectively with return electrode 10, ginseng Examine electrode 12, array-electrode-series 11 is connected；When being normalized operation, induced polarization potential logging instrument works In normalization state, instrument launches signal by the emission electrode on array-electrode-series 11, and this signal is through sending out Radio pole connection terminal is to signal source 1, and return electrode 10 connects terminal by earth signal by return electrode simultaneously Being input to signal source 1, signal source 1 produces tri-kinds of direct currents of 0VDC, 2.5VDC, 5VDC by internal circuit and believes Number, signal selecting circuit 2 selecting 0VDC, this signal is through measuring electrode connecting end 6 to array-electrode-series Measurement electrode on 11, now ground system carries out data acquisition, after this time having gathered, then passes through signal Selection circuit 2 selects 2.5VDC and 5VDC to carry out data acquisition respectively, finally right by software on ground module 7 Gather data three times to be normalized, the final gain obtaining each channel and offset parameter and collection of illustrative plates thereof.

Software on ground module uses normalization specific algorithm as follows:

Channel quantity is N, and the data that the most each channel collection obtains are M_i, i ∈ [1, N], by direct mean value method Can obtain:

Normalization formula is:

In formulaThe average tried to achieve for (1) formula, i.e. value after normalization, M_iFor channel each before normalization Data, GAIN_iAnd Offset_iIt is respectively gain and the side-play amount of respective channel.Owing to the most each channel is right Three signals collecting of 0VDC ,+2.5VDC ,+5VDC data, first select 0VDC's and+2.5VDC 2 Data, after bringing into respectively in formula (2), each channel can obtain a linear equation in two unknowns group, calculates After the value of GAIN and OFFSET when can obtain low signal input range, GAIN value is all answered under normal circumstances Should be distributed in normal state coordinate.Then select the data of+2.5VDC and+5VDC 2, repeat above-mentioned calculating Journey, can obtain GAIN and the OFFSET parameter of high signal input range.Software is formed and includes each channel Gain and the file of offset parameter, during on-the-spot well logging, this document is by routine call of logging well, and participates in calculating, and Gain and offset coordinates collection of illustrative plates can judge the job stability of each channel intuitively.

Fig. 2 is gain distribution plots, and abscissa is channel designator, and vertical coordinate is gain, ideal communication channel Gain should fall on this line of numerical value 1, actually can not be completely the same due to each channel design parameter, Substantially should be distributed in the scope that horizontal line that gain is 1 is the least, if some some deviation is farther out, This channel is then indicated to have problems.

Fig. 3 is offset coordinates scattergram, and abscissa is channel designator, and vertical coordinate is side-play amount, preferable letter The side-play amount in road should be 0, owing to channel parameter exists small error, actually can be substantially distributed in the two of 0 Side, the singular point that deviation 0 value is bigger indicates this channel to there is fault.If using twice-normalization experiment Gain profiles figure and side-play amount scattergram compare, and have the channel of unstable properties and preferably indicate work With.

Claims (3)

1. induced polarization potential logging instrument method for normalizing, including: mainly by array-electrode-series (11), electricity Sub-line road (9), return electrode (10) and remote measurement short circuit connect into instrument string, and connect with ground system (8) Connect the induced polarization potential logging instrument of composition；By signal source (1), signal selecting circuit (2), reference electrode Connect terminal (3), return electrode connects terminal (4), emission electrode connects terminal (5), measure electrode even The induced polarization current potential normalized device that connecting terminal (6) forms；And it is arranged on returning of ground system (8) One changes software module (7), it is characterized in that: return electrode connects terminal (4) and reference electrode connects terminal (3) Being connected with return electrode (10) and reference electrode (12) respectively, emission electrode connects terminal (5) and measures Electrode connecting end (6) is connected with emission electrode and the measurement electrode of array-electrode-series (11) respectively；Launch The signal that emission electrode is sent by electrode connecting end (5) is input to signal source (1), and return electrode connects end Son (4) provides earth signal input for signal source, and signal source (1) produces 0VDC ,+2.5VDC ,+5VDC letter Number, signal selecting circuit (2) selects corresponding signal as required, and this signal is by measuring electrode connecting end Son (6) output measures electrode to each, and reference electrode connects terminal (3) to be provided for apparatus measures circuit Reference potential, downhole instrument electronic circuit (9) and ground system (8) gather the data of each measurement electrode, Finally by normalization software module (7), the measurement data gathered is normalized according to meansigma methods normalization method Process and calculate, it is thus achieved that the gain of each electrode and offset parameter.

Induced polarization potential logging instrument method for normalizing the most according to claim 1, is characterized in that described Normalization computational methods are as follows:

Channel quantity is N, and the data that the most each channel collection obtains are M_i, i ∈ [1, N], by direct mean value method Can obtain $\stackrel{\‾}{M}=\frac{1}{N}\·{\mathrm{\Σ}}_{i=1}^N{M}_i---\left(1\right)$

Normalization formula is: $\stackrel{\‾}{M}=M_i\·{\mathrm{GAIN}}_i+{\mathrm{Offset}}_i---\left(2\right)$

In formulaThe average tried to achieve for (1) formula, i.e. value after normalization, M_iFor channel each before normalization Data, GAIN_iAnd Offset_iIt is respectively gain and the offset parameter of respective channel；

Based on above-mentioned formula (1) and (2), at each channel to 0VDC ,+2.5VDC ,+5VDC three After signals collecting data, first select the data of 0VDC and+2.5VDC 2, bring into respectively in formula (2) After, each channel obtains a linear equation in two unknowns group, obtains GAIN during low signal input range after calculating With the parameter value of OFFSET, then select the data of+2.5VDC and+5VDC 2, repeat above-mentioned calculating Process, obtains GAIN and the OFFSET parameter value of high signal input range.

Induced polarization potential logging instrument method for normalizing the most according to claim 1 and 2, is characterized in that: On the basis of the gain obtaining each electrode and offset parameter, produce gain and side-play amount normalization further Coordinate collection of illustrative plates.