CN203452777U - Hard electrode combined well logging instrument used for measuring drilled well - Google Patents

Abstract

The utility model provides a hard electrode combined well logging instrument used for measuring a drilled well. The well logging instrument comprises a reflux electrode, a transmitting electrode and an electronic circuit, wherein the reflux electrode and the transmitting electrode are respectively provided with an electrode ring, and the electrode rings are connected with one end of the electronic circuit. The well logging instrument is characterized in that the electronic circuit comprises a power supply circuit, a measurement amplifying circuit, a scale circuit, a power control circuit and a communication interface circuit, wherein the power supply circuit supplies power for other circuits, and a gradient signal and a potential signal output by the scale circuit are input to the power control circuit and the communication interface circuit after passing through the measurement amplifying circuit. The well logging instrument has the advantages that the well logging instrument is controlled through a remote sensor, can measure a conventional curve required by a user through one-time descending, and can measure a potential curve and a gradient curve at the same time.

Description

A kind of hard electrode combination logging instrument of measuring drilling well

Technical field:

The utility model belongs to logger field, is specifically related to a kind of hard electrode combination logging instrument of measuring drilling well.

Background technology:

During current domestic well logging, customer requirement provides electrode system data, oil reservoir logging squad is except completing grand slam conventional logging for this reason, also must be more single next plowed the well logging of electrode system, this has not only increased well logging risk, and lengthen while causing taking well, greatly increased the expense cost of drilling company.

Often adopt in the prior art the logging method of conventional, electric-resistance rate, wherein measuring principle, referring to accompanying drawing 1, for measuring the resistance R of a certain resistance, can be applied a power supply to this resistance power supply, measures and flows through the electric current I of this resistance and the voltage drop V at resistance two ends; By Ohm's law, can be obtained the resistance of this resistance.

$R=\frac{V}{I}---\left(1\right)$

Conventional electrical survey (ES) principle is also the method adopting similarly, according to Ohm's law, carrys out Formation Resistivity Measurement.Referring to Fig. 1, an electrodes of A is set in medium, return electrode B is placed on the place of distance electrode A infinity, in distance electrode A a distance, places a pair of measurement electrode M, N, carries out potential difference measurement.Suppose that electrode is point electrode, medium is evenly unlimited, and resistivity of media is ρ.The electric current flowing out from electrode A to all the winds evenly scatters radially, and equipotential plane is to take the sphere that A is the centre of sphere, if measurement electrode M, the distance of N and current electrode is respectively

(dimension of noting resistance ρ is Ω m, and length dimension is m):

The current potential that M is ordered: $V_M=\frac{\mathrm{\ρI}}{4\mathrm{\π}\stackrel{\‾}{\mathrm{AM}}}---\left(2\right)$

The current potential that N is ordered:

$V_N=\frac{\mathrm{\ρI}}{4\mathrm{\π}\stackrel{\‾}{\mathrm{AN}}}---\left(3\right)$

In formula, I is the current strength (ampere) that electrode A flows out.By upper two formulas, can be obtained the potential difference V of M, N point-to-point transmission:

$V=V_M-V_N=\frac{\stackrel{\‾}{\mathrm{MN}}}{4\mathrm{\π}\stackrel{\‾}{\mathrm{AM}}\stackrel{\‾}{\mathrm{AN}}}\mathrm{\ρI}$

So resistivity:

$\mathrm{\ρ}=\frac{4\mathrm{\π}\stackrel{\‾}{\mathrm{AM}}\stackrel{\‾}{\mathrm{AN}}}{\stackrel{\‾}{\mathrm{MN}}}\frac{V}{I}---\left(4\right)$

In formula,

for the distance of electrode M, N point-to-point transmission, order

$K=\frac{4\mathrm{\π}\stackrel{\‾}{\mathrm{AM}}\stackrel{\‾}{\mathrm{AN}}}{\stackrel{\‾}{\mathrm{MN}}}---\left(5\right)$

? $\mathrm{\ρ}=K\frac{V}{I}---\left(6\right)$

In formula: K is called electrode system constant.Formula (5) shows, conventional electrical survey (ES) method is according to Ohm's law, to measure the resistivity on stratum.Formula (6) is the fundamental formular of resistivity logging method.

The combination of electrodes of A, return electrode B and measurement electrode M, N is called electrode system.By formula (4), can be found out, the electric potential gradient between resistivity and M, N has linear dependence.Therefore, kind electrode system is called gradient array.The mid point of M and N is the depth registration point of electrode system.If N electrode is moved to " infinity ", locate, can calculate resistivity by formula (2).At this moment, the current potential that resistivity is ordered with M becomes linear dependence.The electrode system of this structure claims potentiometric electrode system.The mid point of A and M is the depth registration point of potentiometric electrode system.According to principle of reciprocity, electrodes of A, B and measurement electrode M, N reciprocity position, so the value of resistivity is constant.

During practical logging, electrode system is placed in well, and in well, mud is as conductive media matter.The measurement electric current that electrodes of A flows out flows to stratum through mud.The thickness of down-hole formation is limited; Different stratum, its resistivity is different, for permeable formation; Because the intrusion of F forms flushed zone.Therefore, an actual stratum media can not regard evenly unlimited as.Obviously by conventional, electric-resistance rate method Formation Resistivity Measurement, to be subject to the impact of well mud (special salt-water mud), flushed zone and upper and lower shoulder-bed resistivity (SBR).Because actual formation is anisotropic medium heterogeneous, add wellbore effect, the true resistivity that the resistivity that conventional electrical survey (ES) obtains can only be similar to reflection stratum is called apparent resistivity (ρ _a).

${\mathrm{\ρ}}_a=K\frac{V}{I}$

Utility model content:

The utility model, in order to overcome the deficiencies in the prior art, provides a kind of novel hard electrode combination logging instrument, by the design of electronic circuit, can just can carry out the measurement of electrode system data by once going into the well.

The utility model provides a kind of hard electrode combination logging instrument of measuring drilling well, described logging instrument comprises return electrode, emission electrode and electronic circuit, described return electrode and emission electrode are equipped with electrode retaining collar, described electrode retaining collar is connected with one end of electronic circuit, described electronic circuit comprises power circuit, measure amplifying circuit, calibration circuit, power control circuit and communication interface circuit, wherein power circuit provides power supply for other circuit, the gradient signal of described calibration circuit output and electric potential signal are after measuring amplifying circuit, input to power control circuit and communication interface circuit,

Further, described power circuit by power transformer step-down wherein, produces the alternating current of 18V and the alternating current of 8V, then pass through rectifying and wave-filtering, obtain respectively+12V of voltage stabilizing ,-12V and+voltage of 5V;

Further, described measurement amplifying circuit comprises two, and the circuit structure of these two measurement amplifying circuits is identical, comprises wide-band amplifier, bandpass filter, phase-sensitive detector and low pass filter, and wherein measuring-signal is from calibration circuit signal;

Further, the oscillating circuit in power control circuit produces the square-wave signal of 4.587MHz, and then frequency division produces the square-wave signal of 17.5Hz, and plays driving effect by snubber;

Further, described calibration circuit comprises relay, scale resistance and drive circuit;

Further, described communication interface circuit is the core of described electronic circuit, and wherein UDATA, UCK, DSIG realize the three-bus of exchanges data between described combination logging tool and logging remote transmission instrument;

Further, described the spread of the rumours instrument adopts ethernet communication plate.

Further, the length of described logging instrument return electrode is 4445mm, and the length of emission electrode is 4590mm, and the length of electronic circuit is 1080mm, and the external diameter of logging instrument is 92mm.

Further, the measuring point of this logging instrument comprises 2.5M gradient measuring point, 0.45M gradient measuring point, 0.4M electrogram point, SP electrogram point.

The beneficial effects of the utility model are: logging instrument is controlled by the spread of the rumours instrument, realize and once going into the well, and can measure the ordinary curve of customer requirements, also can measure current potential, gradient curve simultaneously.

Accompanying drawing explanation:

Fig. 1 is the conventional electrical survey (ES) schematic diagram of prior art;

Fig. 2 is the structural representation of the hard electrode combination logging instrument of the utility model;

Fig. 3 is the hard electrode combination logging principle of the utility model figure;

Fig. 4 is the power circuit principle figure in the utility model logging instrument;

Fig. 5 is the measurement amplifying circuit schematic diagram in the utility model logging instrument;

Fig. 6 is the power control circuit schematic diagram in the utility model logging instrument;

Fig. 7 is the calibration circuit schematic diagram in the utility model logging instrument;

Fig. 8 is the communication interface circuit schematic diagram in the utility model logging instrument;

Fig. 9 is that the communication of the utility model logging instrument and TCC adopts semiduplex working method schematic diagram.

The specific embodiment:

Following content elaborates to the specific embodiment of the present utility model in connection with Figure of description:

Referring to Fig. 2, be this logging instrument of hard electrode combination of the present utility model, logging instrument is comprised of return electrode 1, emission electrode 2 and electronic circuit 3; Described return electrode 1 and emission electrode 2 are equipped with electrode retaining collar, and described electrode retaining collar is connected with one end of electronic circuit.Wherein, electronic circuit comprises power circuit, measures amplifying circuit, calibration circuit, power control circuit and communication interface circuit.Wherein the length of logging instrument return electrode 1 is 4445mm, the length of emission electrode 2 is 4590mm, the length of electronic circuit is 1080mm, and external diameter is 92mm, and the measuring point of this logging instrument comprises 2.5M gradient measuring point, 0.45M gradient measuring point, 0.4M electrogram point, SP electrogram point.Wherein the electrogram point of 0.4M is 3806mm apart from distance from bottom, and 0.45M gradient measuring point is 3556mm apart from distance from bottom, and 2.5M gradient measuring point is 2586mm apart from distance from bottom; SP electrogram point is 3336mm apart from distance from bottom.

Referring to Fig. 3, hard electrode combination logging instrument of the present utility model is comprised of two relatively independent logging systems: i.e. electrode system well logging and nutural potential logging system.Each subsystem operating principle of logging well is as follows:

Electrode measuring

The basic theory of electrode system well logging is Ohm's law principle.When emission electrode A inputs the alternation square-wave signal of stabilized frequency, constant amplitude, in tested stratum, set up alternating electric field, by the potential difference of measuring between measurement electrode M, N, be proportional to stratum loop resistance rate, can infer the resistivity on stratum.Wherein M0.45, N0.45; M2.5, N2.5 are used for measuring 0.45m and 2.5m gradient; M0.4, N0.4 are used for measuring 0.4m current potential.

Self-potential survey principle

Natural potential is a kind of " naturally " stratum DC potential, has a special-purpose SP electrode to make natural potential sampled point in this logging instrument coil array glass fibre reinforced plastics casing, and this sampled signal is directly delivered to ground instrument by analog signal by cable and processed.SP ring is measured SP signal with armour skin.

Input electrode is calibration circuit respectively, also process is measured the measurement by magnification of amplifying circuit, inputs to power control circuit and communication interface circuit for the gradient of above-mentioned measurement and electric potential signal.

Following content illustrates each physical circuit:

Wherein power circuit is referring to Fig. 4: by ground logging system by part cable core to downhole instrument for 180V, the alternating current of 50Hz, through power transformer (in frame, belonging to a part for power circuit) step-down, produces the alternating current of 18V and the alternating current of 8V.Again through rectifying and wave-filtering, obtain respectively+12V of voltage stabilizing ,-12V and+voltage of 5V, for the circuit on instrument provides power supply.

Wherein V5, V6 avoid regulator block breakdown, shield, and the effect of V11, V12, V13, V14 is the same, have three Voltage stabilizing modules to be arranged on radiating block.

Measure amplification circuit diagram referring to Fig. 5: each channel circuit structure of two measurement amplifying circuits is identical, each passage forms by wide-band amplifier, bandpass filter, phase-sensitive detector and low pass filter, measuring-signal is from calibration circuit plate, the first order is broadband amplifying circuit, voltage-stabiliser tube and relevant resistance capacitance are used for limiting the amplitude of input signal, its gain G=1+ (49.4k/R _g).

Bandpass filter is by R ₆, R ₈, R ₉, R ₁₀, C ₁, C ₂, U ₄(U4 is that double operational amplifier is used respectively U4A, and U4B represents, is used for distinguishing with chip Zhong Na road discharge circuit) and other relevant resistance capacitances form, and its centre frequency is 17.5Hz, and gain is 5.

Phase-sensitive detector is comprised of analog switch U6 and filter circuit.The control signal of U6 is taken from 17.5Hz reference signal.When 1, the 9 end 17.5Hz reference signals of U6 are high level, the 2-3 of U6,10-11 termination are led to; And 3-4,11-12 hold disconnection.The 17.5Hz signal of at this moment U4 output is in positive half-wave, obtains the positive signal of a full-wave rectification on filter capacitor C7 and C10; And when reference signal is low level, the 2-3 of U6,10-11 disconnect, 3-4,11-12 connect, and the 17.5Hz signal of being exported from U4 becomes negative half-wave.On filter capacitor C7 and C10, obtain the negative signal of a full-wave rectification, the amplitude of the DC component of signal is:

$V_{\mathrm{DC}}=\frac{2}{\mathrm{\π}}{V}_{\mathrm{iP}}=\frac{2\sqrt{2}}{\mathrm{\π}}{V}_{\mathrm{irms}}$

In formula, V _ipthe peak value of-input signal; V _irmsthe virtual value of-input signal.

The gain of phase-sensitive detector is:

$G=\frac{V_{\mathrm{DC}}}{V_{\mathrm{irms}}}=\frac{2\sqrt{2}}{\mathrm{\π}}\≈0.9$

For N/SP passage, its input signal is from SP electrode and cable armour skin, and SP signal is a DC level of picking up from natural potential, and natural potential is the DC level under a kind of stratum natural state.Signal is first sent to next stage by the LPF of two-stage afterwards again by the amplification of broadband amplifying circuit.

Power control circuit as shown in Figure 6, wherein Y and U1(CD4060) form oscillating circuit, produce the square-wave signal of 4.587MHz, then by U1, U2(CD4060) frequency division produces the square-wave signal of 17.5Hz, by U3(MC14504) snubber plays driving effect.

The signal PC coming from power control circuit has determined U4(ADG436) size of the 17.5Hz signal of output, U5B, U5A(OPA2132U) and the relevant resistance capacitance organization center frequency bandpass filtering that is 17.5Hz, the multiplication factor of U5B is in 1.41 left and right, the multiplication factor of U5A is also in 1.41 left and right, and so far the square-wave signal of 17.5Hz has become the sine wave signal of 17.5Hz.Afterwards by U6, U7(PA61) carry out electric current amplification.

Calibration circuit as shown in Figure 7, by relay K 1, K2, K3, K4; Scale resistance R 1, R2, R3, R4; And drive circuit forms.Wherein K1, K2, K3, K4 are electromagnetic relay.Drive circuit comprises resistance R 6, R7, R8, R9, R10, capacitor C 1, C2, C3, transistor V1, V2, V3, V4.

When RELAY is low level, V1, V2 cut-off, K1, K2, K3, K4 must not electricity, in state at outer quarter, V1, V2 conducting when RELAY is high level, K1, K2, K3, K4 work, make instrument from outer quarter state be switched to state at interior quarter.

Under state at quarter, CI+ is inputted by R5, K1B-8 outside, through K1B-6, outputs to A transmitting, and B receives K1A-4 input, turns back to CI-form current supply circuit through K1A-2 output.

Under interior quarter state, CI+ is inputted by R5, K1B-8, through K1B-7 output, through R1, R2, R3, R4, to K1A-3 input, through K1A-2 output, turns back to CI-composition current supply circuit.Gradiometry 0.45M gathers from R1 two ends, and gradiometry 2.5M gathers from R3 two ends, and gradiometry 4.0M gathers from R4 two ends, and potential measurement 0.4M gathers from R1+R2+R3 two ends.

As shown in Figure 8, communication interface circuit is the core of logging instrument electronic circuit to communication interface circuit, and it completes the communication between this logger and TCC, and the function such as instrument control, A/D conversion, D/A conversion, power control, data acquisition.

In Fig. 8, UDATA/GO, UCK, DSIG are combination logging tool and TCC(the spread of the rumours instrument) between realize three buses (DTB bus) of exchanges data, instrument connects with adopting a kind of daisy chain type being connected of bus, the communication of combination logging tool and TCC adopts semiduplex working method, as shown in Figure 9.The communication signal of combination logging tool and TCC has three:

Uploading data and GOP pulse signal: UDATA/GO

Upload clock: UCK

Lower teletype command: DSIG

Wherein UDATA is uploading data, and GOP pulse is sequential cue, and both share same holding wire.GOP pulse frequency is 60Hz or 15Hz, by under TCC, pass, when GOP pulse arrives circuit, this circuit is ready to the well logging data to be transferred of collection, until the UCK that TCC sends is when arrive, by UCK, data are shifted out by turn, form UDATA data upload to TCC, UDATA has passed rear TCC and has just sent DSIG signal, combination logging tool is controlled, combination logging tool is decoded after receiving DSIG signal immediately, complete command operating (scale, well logging), so far, complete a complete data communication cycle, until the arrival of next GOP pulse, start next data acquisition and upload the cycle.

The Address Recognition of whole circuit, command decode, control and data are transmitted in CPLD complex programmable logic module and complete; A/D conversion, power are controlled and by single-chip microcomputer, are realized.Thereby reaching scale controls and uploading data parallel-serial conversion.

After UCK signal is reverse by triode V3, by level conversion, be 5V.GOP impulse amplitude on UDATA/GO signal is 3.6V, UDATA signal amplitude is 1.2V, V10 is a comparator, threshold threshold value is 2.4V, therefore, GOP pulse is converted to 5V pulse by U10 and passes to CPLD, and the UDATA signal of 1.2V cannot pass through, thus separated with UDATA signal of the level conversion that has realized GOP pulse.DSIG signal is that amplitude is the two-way return-to zero system signal of 1.2V, itself has comprised data message and clock information, it is by comparator U8, U9, isolates clock signal and data-signal is given CPLD when level signal is converted to 5V, by CPLD, is decoded and is sent control signal.Data register in CPLD is parallel data transformed into serial data, under the triggering of uploading clock UCK, serial data delivered to TCC by bus driver V4 uploading data UDATA and encodes to process and upload to ground instrument and process.Wherein TCC is the communication Instrument of connecting downhole measuring system and ground instrument, belongs to the state of the art, can adopt ethernet communication plate, can realize the spread of the rumours function of signal.

By the above-mentioned designs such as electronic circuit, logging instrument of the present utility model is controlled by the spread of the rumours instrument, realizes and once going into the well, and can measure the ordinary curve of customer requirements, also can measure current potential, gradient curve simultaneously.

Above content is in conjunction with specific embodiment further detailed description of the utility model, can not assert that concrete enforcement of the present utility model is confined to these explanations.For the utility model person of an ordinary skill in the technical field, without departing from the concept of the premise utility, can also make some simple deduction or replace, all should be considered as belonging to protection domain of the present utility model.

Claims (9)

1. a hard electrode combination logging instrument of measuring drilling well, described logging instrument comprises return electrode, emission electrode and electronic circuit, described return electrode and emission electrode are equipped with electrode retaining collar, described electrode retaining collar is connected with one end of electronic circuit, it is characterized in that, described electronic circuit comprises power circuit, measure amplifying circuit, calibration circuit, power control circuit and communication interface circuit, wherein power circuit provides power supply for other circuit, the gradient signal of described calibration circuit output and electric potential signal are after measuring amplifying circuit, input to power control circuit and communication interface circuit.

2. logging instrument according to claim 1, is characterized in that, described power circuit by power transformer step-down wherein, produces the alternating current of 18V and the alternating current of 8V, then pass through rectifying and wave-filtering, obtain respectively+12V of voltage stabilizing ,-12V and+voltage of 5V.

3. logging instrument according to claim 1, it is characterized in that, described measurement amplifying circuit comprises two, the circuit structure of these two measurement amplifying circuits is identical, comprise wide-band amplifier, bandpass filter, phase-sensitive detector and low pass filter, wherein measuring-signal is from calibration circuit signal.

4. logging instrument according to claim 1, is characterized in that, the oscillating circuit in power control circuit produces the square-wave signal of 4.587MHz, and then frequency division produces the square-wave signal of 17.5Hz, and plays driving effect by snubber.

5. logging instrument according to claim 1, is characterized in that, described calibration circuit comprises relay, scale resistance and drive circuit.

6. logging instrument according to claim 1, is characterized in that, described communication interface circuit is the core of described electronic circuit, and wherein UDATA, UCK, DSIG realize the three-bus of exchanges data between described combination logging tool and logging remote transmission instrument.

7. logging instrument according to claim 6, is characterized in that, described the spread of the rumours instrument adopts ethernet communication plate.

8. logging instrument according to claim 1, is characterized in that, the length of described logging instrument return electrode is 4445mm, and the length of emission electrode is 4590mm, and the length of electronic circuit is 1080mm, and the external diameter of logging instrument is 92mm.

9. logging instrument according to claim 1, is characterized in that, the measuring point of this logging instrument comprises 2.5M gradient measuring point, 0.45M gradient measuring point, 0.4M electrogram point, SP electrogram point.

Images