CN103437761B - A kind of hard electrode combination logging instrument measuring drilling well - Google Patents

Abstract

The invention provides a kind of hard electrode combination logging instrument measuring drilling well, described logging instrument comprises return electrode, emission electrode and electronic circuit composition, and described logging instrument can realize once going into the well and just can carry out the measurement of electrode system data; Described electronic circuit comprises power circuit, measuring and amplifying circuit, calibration circuit, power control circuit and communication interface circuit.The invention has the beneficial effects as follows: logging instrument, by the spread of the rumours instrument controlling, realizes once going into the well, can measure the ordinary curve that user requires, also can measure current potential, gradient curve simultaneously.

Description

A kind of hard electrode combination logging instrument measuring drilling well

Technical field:

The invention belongs to logger field, be specifically related to a kind of hard electrode combination logging instrument 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 more single next plowed the well logging of electrode system, this not only adds well logging risk, and lengthen when causing taking well, considerably increase the expense cost of drilling company.

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

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

Conventional electrical survey (ES) principle is also adopt similar method, carrys out Formation Resistivity Measurement according to Ohm's law.See Fig. 1, arrange an electrodes of A in media as well, return electrode B is placed on the place of distance electrode A infinity, places a pair measurement electrode M, N, carry out potential difference measurement in distance electrode A a distance.Assuming that electrode is point electrode, medium is evenly unlimited, and resistivity of media is ρ.The electric current then flowed out from electrode A to all the winds evenly scatters radially, and equipotential plane take A as the sphere of the centre of sphere, if the distance of measurement electrode M, N and current electrode is respectively (dimension of attention resistance ρ is Ω m, and length dimension is m) then:

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

The current potential of N point:

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

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

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

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

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

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

In formula: K is called electrode system constant.Formula (5) shows, conventional electrical survey (ES) method is to measure the resistivity on stratum according to Ohm's law.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.As can be seen from formula (4), resistivity and the electric potential gradient between M, N have linear dependence.Therefore, this 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 " place, then can calculate resistivity by formula (2).At this moment, resistivity becomes linear dependence with the current potential of M point.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; Flushed zone is formed due to the intrusion of F.Therefore, an actual stratum media can not regard evenly unlimited as.Obviously the impact of well mud (special salt-water mud), flushed zone and upper and lower shoulder-bed resistivity (SBR) will be subject to by conventional, electric-resistance rate method Formation Resistivity Measurement.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).

${\mathrm{\ρ}}_a=K\frac{V}{I}$

Summary of the invention:

The present invention, 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, just can carry out the measurement of electrode system data by once going into the well.

The invention provides a kind of hard electrode combination logging instrument measuring drilling well, described logging instrument comprises return electrode, emission electrode and electronic circuit, and described logging instrument can realize once going into the well and just can carry out the measurement of electrode system data;

Further, described electronic circuit comprises power circuit, measuring and amplifying circuit, calibration circuit, power control circuit and communication interface circuit;

Further, described power circuit comprises by power transformer step-down wherein, produce the alternating current of 18V and the alternating current of 8V, then obtain the voltage of+12V ,-12V and+5V respectively through rectifying and wave-filtering, voltage stabilizing, for other circuit on described logging instrument provide power supply;

Further, described measuring and amplifying circuit comprises two, and the circuit structure of these two measuring and amplifying circuit 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 K 1, K2, K3, K4; Scale resistance R1, R2, R3, R4 and drive circuit, wherein drive circuit comprises resistance R6, R7, R8, R9, R10, electric capacity C1, C2, C3 and transistor V1, V2, V3, V4; When RELAY is low level, V1, V2 end, and K1, K2, K3, K4 no power is in state at outer quarter, when RELAY is high level, and V1, V2 conducting, K1, K2, K3, K4 work, and make logging instrument be switched to state at interior quarter from state at outer quarter;

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

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

Further, described the spread of the rumours instrument adopts ethernet communication plate to realize down-hole and aboveground communication function.

The invention has the beneficial effects as follows: logging instrument is by the spread of the rumours instrument controlling, realize once going into the well, the ordinary curve can measuring user's requirement (is nine fundamental curves of petroleum industry regulation, i.e. three porosity curve: neutron, density, acoustic wave apparatus curve, three resistivity curves: microballoon, side direction or induction instrument aratus dark/in/shallow resistivity curve, three lithology curves: gamma ray curve, spontaneous potential curve, CAL), also can measure current potential, gradient curve simultaneously.

Accompanying drawing illustrates:

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 present invention;

Fig. 3 is the hard electrode combination logging principle figure of the present invention;

Fig. 4 is the power circuit principle figure in logging instrument of the present invention;

Fig. 5 is the measuring and amplifying circuit theory diagrams in logging instrument of the present invention;

Fig. 6 is the power control circuit schematic diagram in logging instrument of the present invention;

Fig. 7 is the calibration circuit schematic diagram in logging instrument of the present invention;

Fig. 8 is the communication interface circuit schematic diagram in logging instrument of the present invention;

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

Detailed description of the invention:

Following content will elaborate to the specific embodiment of the present invention in conjunction with Figure of description:

See Fig. 2, be this logging instrument of hard electrode combination of the present invention, logging instrument is made up 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, measuring and 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 be 3806mm, 0.45M gradient measuring point is 3556mm, 2.5M gradient measuring point apart from distance from bottom apart from distance from bottom is 2586mm apart from distance from bottom; SP electrogram point is 3336mm apart from distance from bottom.

See Fig. 3, hard electrode combination logging instrument of the present invention is made up of two relatively independent logging systems: namely electrode system is logged well and nutural potential logging system.Each well logging subsystem operating principle is as follows:

Electrode measuring

The basic theory of electrode system well logging is ohmic.When the alternation square-wave signal of emission electrode A input stabilized frequency, constant amplitude, in tested stratum, set up alternating electric field, be proportional to stratum loop resistance rate by the potential difference measured between measurement electrode M, N, the resistivity on stratum can be inferred.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, and have a special SP electrode to make natural potential sampled point in this logging instrument coil array glass fibre reinforced plastics casing, analog signal is directly delivered to ground instrument by cable and processed by this sampled signal.SP ring and armour skin measure SP signal.

The gradient of above-mentioned measurement and electric potential signal input electrode system calibration circuit through the measurement by magnification of measuring and amplifying circuit, input to power control circuit and communication interface circuit respectively.

Following content illustrates each physical circuit:

Wherein power circuit is see Fig. 4: the alternating current being supplied 180V, 50Hz by ground logging system by part cable core to downhole instrument, 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.The voltage of+12V ,-12V and+5V is obtained again respectively, for the circuit on instrument provides power supply through rectifying and wave-filtering, voltage stabilizing.

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.

Measuring and amplifying circuit diagram is identical see each channel circuit structure of Fig. 5: two pieces of measuring and amplifying circuit, 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 uses U4A respectively, and U4B represents, be used for differentiation chip Zhong Na road discharge circuit) and other relevant resistance capacitances compositions, its centre frequency is 17.5Hz, and gain is 5.

Phase-sensitive detector is made up of analog switch U6 and filter circuit.The control signal of U6 takes from 17.5Hz reference signal.When 1, the 9 end 17.5Hz reference signals of U6 are high level, 2-3,10-11 termination of U6 is led to; And 3-4,11-12 end disconnects.At this moment the 17.5Hz signal that U4 exports is in positive half-wave, and filter capacitor C7 and C10 obtains the positive signal of a full-wave rectification; And when reference signal is low level, 2-3,10-11 of U6 disconnect, 3-4,11-12 connect, and the 17.5Hz signal exported from U4 becomes negative half-wave.Filter capacitor C7 and C10 obtains the negative signal of a full-wave rectification, and 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 picking up from natural potential, and natural potential is the DC level under a kind of stratum natural state.Signal is sent to next stage by the LPF of two-stage after first being amplified by broadband amplifying circuit again.

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 come from power control circuit determines U4(ADG436) size of 17.5Hz signal that exports, U5B, U5A(OPA2132U) and relevant resistance capacitance organization center frequency be the bandpass filtering of 17.5Hz, the multiplication factor of U5B is about 1.41, the multiplication factor of U5A is also about 1.41, and so far the square-wave signal of 17.5Hz becomes the sine wave signal of 17.5Hz.Afterwards by U6, U7(PA61) carry out Current amplifier.

Calibration circuit as shown in Figure 7, by relay K 1, K2, K3, K4; Scale resistance R1, R2, R3, R4; And drive circuit composition.Wherein K1, K2, K3, K4 are electromagnetic relay.Drive circuit comprises resistance R6, R7, R8, R9, R10, electric capacity C1, C2, C3, transistor V1, V2, V3, V4.

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

Outside under state at quarter, CI+ is inputted by R5, K1B-8, outputs to A launch through K1B-6, and B receives K1A-4 input, exports turn back to CI-composition current supply circuit through K1A-2.

Under interior quarter state, CI+ is inputted by R5, K1B-8, exports through K1B-7, through R1, R2, R3, R4 to K1A-3 input, exports turn back to CI-composition current supply circuit through K1A-2.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 controlling, 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, the connection of instrument and bus adopts a kind of daisy chain type to connect, 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, pass by under TCC, when GOP pulse arrives circuit, the well logging data to be transferred of collection is ready to by this circuit, until when the UCK that TCC sends arrives, 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 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 control then to be realized by single-chip microcomputer.Thus reach scale control and uploading data parallel-serial conversion.

UCK signal by triode V3 oppositely after be 5V by level conversion.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 achieve GOP pulse level conversion and with being separated of UDATA signal.The two-way return-to zero system signal of DSIG signal to be amplitude be 1.2V, itself includes data message and clock information, it is by comparator U8, U9, isolates clock signal and data-signal gives CPLD while level signal is converted to 5V, carries out decoding send control signal by CPLD.Data register in CPLD converts parallel data to serial data, under the triggering of uploading clock UCK, serial data is delivered to TCC by bus driver V4 uploading data UDATA and carries out coded treatment 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 designs such as above-mentioned electronic circuits, logging instrument of the present invention, by the spread of the rumours instrument controlling, realizes once going into the well, can measure the ordinary curve that user requires, also can measure current potential, gradient curve simultaneously.

Above content is in conjunction with detailed description of the invention further description made for the present invention, can not assert that specific embodiment of the invention is confined to these explanations.For general technical staff of the technical field of the invention, without departing from the inventive concept of the premise, some simple deduction or replace can also be made, all should be considered as belonging to protection scope of the present invention.

Claims (6)

1. measure a hard electrode combination logging instrument for drilling well, described logging instrument comprises return electrode, emission electrode and electronic circuit, it is characterized in that, described logging instrument can realize once going into the well and just can carry out the measurement of electrode system data;

Described electronic circuit comprises power circuit, measuring and amplifying circuit, calibration circuit, power control circuit and communication interface circuit;

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

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

2. logging instrument according to claim 1, it is characterized in that, described power circuit is by power transformer step-down wherein, produce the alternating current of 18V and the alternating current of 8V, the voltage of+12V ,-12V and+5V is obtained again respectively, for other circuit on described logging instrument provide power supply through rectifying and wave-filtering, voltage stabilizing.

3. logging instrument according to claim 1, it is characterized in that, described measuring and amplifying circuit comprises two, the circuit structure of these two measuring and amplifying circuit 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 2, is characterized in that, described calibration circuit comprises relay K 1, K2, K3, K4; Scale resistance R1, R2, R3, R4 and drive circuit, wherein drive circuit comprises resistance R6, R7, R8, R9, R10, electric capacity C1, C2, C3 and transistor V1, V2, V3, V4; When RELAY is low level, V1, V2 end, and K1, K2, K3, K4 no power is in state at outer quarter, and when RELAY is high level, V1, V2 conducting, K1, K2, K3, K4 work, and make logging instrument be switched to state at interior quarter from state at outer quarter.

6. logging instrument according to claim 1, is characterized in that, described the spread of the rumours instrument adopts ethernet communication plate to realize down-hole and aboveground communication function.