CN212031351U - Working frequency signal processing circuit of petroleum formation resistivity measuring instrument - Google Patents
Working frequency signal processing circuit of petroleum formation resistivity measuring instrument Download PDFInfo
- Publication number
- CN212031351U CN212031351U CN202020647820.0U CN202020647820U CN212031351U CN 212031351 U CN212031351 U CN 212031351U CN 202020647820 U CN202020647820 U CN 202020647820U CN 212031351 U CN212031351 U CN 212031351U
- Authority
- CN
- China
- Prior art keywords
- circuit
- signal
- current
- voltage
- measuring instrument
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Abstract
The utility model discloses a working frequency signal processing circuit of an oil formation resistivity measuring instrument, which comprises a voltage mixing signal circuit, a voltage pre-amplifying circuit, a current mixing signal circuit, a current pre-amplifying circuit, a multi-channel analog-to-digital converter circuit and a DSP interface circuit, wherein the voltage mixing signal circuit is connected with the voltage pre-amplifying circuit; the voltage pre-amplification circuit is connected with the multi-channel analog-to-digital converter circuit; the current mixing signal circuit is connected to the current preamplifier circuit; the current preamplification circuit is connected with the multi-channel analog-to-digital converter circuit; the multichannel analog-to-digital converter circuit performs chopping and analog-to-digital conversion on the processed mixing voltage signal and the processed mixing current signal to obtain a digital voltage signal and a digital current signal; the DSP interface circuit is connected with the multi-channel analog-to-digital converter circuit. The circuit can effectively reduce the number of devices of the analog circuit, thereby reducing the power consumption of the power supply.
Description
Technical Field
The utility model belongs to the technical field of the oil and gas is surveyed, concretely relates to oil formation resistivity measuring instrument's operating frequency signal processing circuit.
Background
The double lateral logging instrument is a main logging instrument for measuring the formation resistivity, researching the change of the formation radial resistivity, calculating the oil saturation and determining the amount of movable oil. When the dual laterolog instrument is used for measuring voltage or current, the common method is that the mixed frequency signals of two or more inherent working frequencies of the instrument are pre-amplified, then separated by an active frequency-selecting network circuit, and then full-wave rectified and shaped respectively to obtain a direct-current voltage value having a linear proportional relation with the measured signal.
However, the number of analog circuit devices of the working frequency signal processing circuit of the existing petroleum formation resistivity measuring instrument is large, which results in large power consumption of a power supply. With the rapid development of the oil exploration logging technology, the logging operation efficiency needs to be improved and the power consumption needs to be reduced urgently.
SUMMERY OF THE UTILITY MODEL
In order to solve the above-mentioned problem that exists among the prior art, the utility model provides a petroleum formation resistivity measuring instrument's operating frequency signal processing circuit. The to-be-solved technical problem of the utility model is realized through following technical scheme:
the utility model provides a working frequency signal processing circuit of an oil formation resistivity measuring instrument, which comprises a voltage mixing signal circuit, a voltage preamplification circuit, a current mixing signal circuit, a current preamplification circuit, a multi-channel analog-to-digital converter circuit and a DSP interface circuit, wherein,
the voltage mixing signal circuit is connected with the voltage pre-amplifying circuit and is used for acquiring original mixing voltage signals of a shallow side main current and a deep side main current of the petroleum formation resistivity measuring instrument and transmitting the original mixing voltage signals to the voltage pre-amplifying circuit;
the voltage pre-amplification circuit is connected with the multichannel analog-to-digital converter circuit and used for coupling and amplifying the original mixing voltage signal to obtain a processed mixing voltage signal and transmitting the processed mixing voltage signal to the multichannel analog-to-digital converter circuit;
the current frequency mixing signal circuit is connected to the current preamplifier circuit and used for acquiring original frequency mixing current signals of a shallow side main current and a deep side main current of the petroleum formation resistivity measuring instrument and transmitting the original frequency mixing current signals to the current preamplifier circuit;
the current preamplification circuit is connected with the multichannel analog-to-digital converter circuit and is used for coupling and amplifying the original mixing current signal to obtain a processed mixing current signal and transmitting the processed mixing current signal to the multichannel analog-to-digital converter circuit;
the multichannel analog-to-digital converter circuit can input a first square wave signal and a second square wave signal, and is used for performing chopping and analog-to-digital conversion on the processed mixing voltage signal and the processed mixing current signal through the first square wave signal and the second square wave signal respectively to obtain a digital voltage signal and a digital current signal;
the DSP interface circuit is connected with the multi-channel analog-to-digital converter circuit and is used for respectively carrying out data processing on the digital voltage signals and the digital current signals so as to obtain the amplitude of deep lateral voltage signals, the amplitude of shallow lateral voltage signals, the amplitude of deep lateral current signals and the amplitude of shallow lateral current signals and generate deep lateral power control signals and shallow lateral power control signals.
In an embodiment of the present invention, the working frequency signal processing circuit of the oil formation resistivity measuring instrument further includes a voltage amplifying coupling transformer, connected between the voltage mixing signal circuit and the voltage pre-amplifying circuit, for coupling and amplifying the voltage signal of the deep lateral main current and the voltage signal of the shallow lateral main current respectively.
In an embodiment of the present invention, the working frequency signal processing circuit of the petroleum formation resistivity measuring instrument further includes a current amplifying coupling transformer, connected between the current mixing signal circuit and the current pre-amplifying circuit, for coupling and amplifying the current signal of the deep lateral main current and the current signal of the shallow lateral main current respectively.
The utility model discloses an embodiment, DSP interface circuit includes filtering unit and arithmetic unit, wherein, filtering unit is used for right digital voltage signal with digital current signal carries out filtering process, arithmetic unit is used for being right through the filtering digital voltage signal with digital current signal carries out the discrete Fourier transform to obtain dark lateral voltage signal amplitude, shallow lateral voltage signal amplitude, dark lateral current signal amplitude and shallow lateral current signal amplitude.
In an embodiment of the present invention, the first square wave signal is a 35Hz square wave signal.
In an embodiment of the present invention, the second square wave signal is a 280Hz square wave signal.
In one embodiment of the present invention, the multi-channel analog-to-digital converter circuit is a six-channel analog-to-digital converter circuit.
The utility model discloses an in the embodiment, DSP interface circuit still is provided with bus interface, bus interface connection remote control system for with remote control system carries out the data interaction.
Compared with the prior art, the beneficial effects of the utility model reside in that:
1. the utility model discloses a petroleum formation resistivity measuring instrument's operating frequency signal processing circuit can effectively reduce analog circuit's device quantity to reduce the power consumption.
2. The working frequency signal processing circuit adopts the DSP interface circuit to perform data processing and operation, compared with the traditional microprocessor circuit, the DSP interface circuit has high operation speed and high obtained data precision.
The present invention will be described in further detail with reference to the accompanying drawings and examples.
Drawings
FIG. 1 is a schematic diagram of an operating frequency signal processing circuit of a prior art petroleum formation resistivity measuring instrument;
fig. 2 is a block diagram of an operating frequency signal processing circuit of an oil formation resistivity measuring instrument according to an embodiment of the present invention;
fig. 3 is a schematic structural diagram of an operating frequency signal processing circuit of an oil formation resistivity measuring instrument according to an embodiment of the present invention;
fig. 4 is a schematic structural diagram of a DSP interface circuit according to an embodiment of the present invention.
Detailed Description
In order to further explain the technical means and effects of the present invention adopted to achieve the objectives of the present invention, the following description will be made in conjunction with the accompanying drawings and the detailed description of the embodiments, to provide a working frequency signal processing circuit of an oil formation resistivity measuring instrument.
The foregoing and other technical matters, features and effects of the present invention will be apparent from the following detailed description of the embodiments, which is to be read in connection with the accompanying drawings. The technical means and effects of the present invention to achieve the predetermined objects can be more deeply and specifically understood through the description of the specific embodiments, however, the attached drawings are only for reference and description and are not intended to limit the technical solution of the present invention.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that an article or device that comprises a list of elements does not include only those elements but may include other elements not expressly listed. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of additional like elements in the article or device comprising the element.
Referring to fig. 1, fig. 1 is a schematic structural diagram of an operating frequency signal processing circuit of a prior art petroleum formation resistivity measuring instrument. As shown in the figure, the working frequency signal processing circuit comprises a voltage mixing signal circuit 1 ', a voltage pre-amplification circuit 2 ', a 35Hz band-pass filter circuit 3 ', a 35Hz phase-sensitive detection circuit 4 ', a low-pass filter circuit 5 ', a 280Hz band-pass filter circuit 6 ', a 280Hz phase-sensitive detection circuit 7 ', a low-pass filter circuit 8 ', a current mixing signal circuit 9 ', a current pre-amplification circuit 10 ', a 35Hz band-pass filter circuit 11 ', a 35Hz phase-sensitive detection circuit 12 ', a low-pass filter circuit 13 ', a 280Hz band-pass filter circuit 14 ', a 280Hz phase-sensitive detection circuit 15 ', a low-pass filter circuit 16 ', a multi-channel gating switch circuit 17 ', an analog-to-digital conversion circuit 18 ', a microprocessor (CPU) circuit 19 ', a voltage amplification coupling transformer T1 ' and a current amplification coupling transformer T2 '.
The working principle of the working frequency signal processing circuit is as follows:
the original mixed frequency voltage signals of the deep side main current and the shallow side main current generated by the voltage mixed frequency signal circuit 1 ' are sent to a voltage preamplification circuit 2 ' through a voltage amplification coupling transformer T1, then are divided into two paths, one path is the deep side voltage, and a deep side voltage measurement signal VD (analog direct current signal) is obtained through a 35Hz band-pass amplification circuit 3 ', a 35Hz phase-sensitive detection circuit 4 ' and a low-pass filter circuit 5 '; the other path is shallow lateral voltage, and a shallow lateral voltage measurement signal VS (analog direct current signal) is obtained through a 280Hz band-pass filter circuit 6 ', a 280Hz phase-sensitive detection circuit 7 ' and a low-pass filter circuit 8 '.
The original mixed current signals of the deep side main current and the shallow side main current generated by the current mixing signal circuit 9 ' are sent to a current preamplification circuit 10 ' through a current amplification coupling transformer T2, then the signals are divided into two paths, one path is the deep side current, and a deep side current measurement signal ID (analog direct current signal) is obtained through a 35Hz band-pass filter circuit 11 ', a 35Hz phase-sensitive detection circuit 12 ' and a low-pass filter circuit 13 '; the other path IS shallow lateral current, and a shallow lateral current measuring signal IS analog direct current signal IS obtained through a 280Hz band-pass filter circuit 14 ', a 280Hz phase-sensitive detection circuit 15 ' and a low-pass filter circuit 16 '.
Then, four groups of analog direct current signals of VD, VS, ID and IS are all sent to a multi-channel gating switch circuit 17 ', gated output IS sent to an analog-to-digital conversion circuit (ADC converter) 18', and then sent to a microprocessor (CPU) for data processing and operation.
The working frequency signal processing circuit of the existing petroleum formation resistivity measuring instrument has more analog circuit devices, which results in larger power consumption of a power supply.
In order to solve the above-mentioned problem of current operating frequency signal processing circuit, the embodiment of the utility model provides a petroleum formation resistivity measuring instrument's modified operating frequency signal processing circuit. Referring to fig. 2, fig. 2 is a block diagram of an operating frequency signal processing circuit of an oil formation resistivity measuring instrument according to an embodiment of the present invention. The working frequency signal processing circuit of the present embodiment includes a voltage mixing signal circuit 1, a voltage pre-amplifying circuit 2, a current mixing signal circuit 3, a current pre-amplifying circuit 4, a multi-channel analog-to-digital converter circuit 5, and a DSP (digital signal processor) interface circuit 6.
The voltage mixing signal circuit 1 is connected with the voltage pre-amplifying circuit 2 and used for obtaining original mixing voltage signals of a shallow side main current and a deep side main current of the petroleum formation resistivity measuring instrument and transmitting the original mixing voltage signals to the voltage pre-amplifying circuit 2.
The voltage pre-amplifying circuit 2 is connected to the multi-channel analog-to-digital converter circuit 5, and is configured to perform coupling amplification on the original mixing voltage signal, obtain a processed mixing voltage signal, and transmit the processed mixing voltage signal to the multi-channel analog-to-digital converter circuit 5.
The current mixing signal circuit 3 is connected to the current preamplifier circuit 4, and is used for acquiring original mixing current signals of a shallow side main current and a deep side main current of the petroleum formation resistivity measuring instrument and transmitting the original mixing current signals to the current preamplifier circuit 4.
The current preamplification circuit 4 is connected with the multichannel analog-to-digital converter circuit 5 and is used for coupling and amplifying the original mixing current signal to obtain a processed mixing current signal and transmitting the mixing current signal to the multichannel analog-to-digital converter circuit 5.
The multichannel analog-to-digital converter circuit 5 can input a first square wave signal 7 and a second square wave signal 8, and is configured to perform chopping and analog-to-digital conversion on the processed mixed voltage signal and the processed mixed current signal through the first square wave signal 7 and the second square wave signal 8, respectively, to obtain a digital voltage signal and a digital current signal. Preferably, the first square wave signal 7 is a 35Hz square wave signal and the second square wave signal 8 is a 280Hz square wave signal.
Specifically, a 35Hz first square wave signal 7 and a 280Hz second square wave signal 8 are input into the multichannel analog-to-digital converter circuit 5, and then the multichannel analog-to-digital converter circuit 5 performs chopping conversion on the 35Hz first square wave signal 7, adjusts the processed mixed voltage signal sent by the voltage preamplifier circuit 2, and then selects and sends the mixed voltage signal to the DSP interface circuit 6; similarly, the multichannel analog-to-digital converter circuit 5 chops, converts and adjusts the processed mixed voltage signal sent by the current pre-amplifying circuit 4 through the 280Hz second square wave signal 8, and sends the mixed voltage signal to the DSP interface circuit 6 in a gating mode. Preferably, the multi-channel analog-to-digital converter circuit 5 of the present embodiment is a six-channel analog-to-digital converter circuit, the analog-to-digital converter circuit module is a 6-channel 16-bit ADC, the differential type positive and negative level input value range is large (-16.5V- +16.5V), the power consumption is small (0.52W), the conversion speed is fast (800kSPS-PAR, 530kSPS-SER), the working temperature range is large-40 ℃ to 175 ℃, and each channel has overcurrent and high-voltage electrostatic protection.
The DSP interface circuit 6 is connected to the multi-channel analog-to-digital converter circuit 5, and is configured to perform data processing on the digital voltage signal and the digital current signal, respectively, to obtain a deep lateral voltage signal amplitude, a shallow lateral voltage signal amplitude, a deep lateral current signal amplitude, and a shallow lateral current signal amplitude, and to generate a deep lateral power control signal and a shallow lateral power control signal. In particular, the DSP interface circuit 6 is a circuit that is digitally represented and processed. Compared with the traditional microprocessor circuit, the DSP interface circuit has high operation speed and high precision of the obtained data.
Further, please refer to fig. 3, fig. 3 is a schematic structural diagram of an operating frequency signal processing circuit of an oil formation resistivity measuring instrument according to an embodiment of the present invention. The working frequency signal processing circuit further comprises a voltage amplification coupling transformer T1 connected between the voltage mixing signal circuit 1 and the voltage preamplification circuit 2 and used for respectively carrying out coupling amplification on the voltage signal of the deep side main current and the voltage signal of the shallow side main current.
Furthermore, the operating frequency signal processing circuit further comprises a current amplifying coupling transformer T2 connected between the current mixing signal circuit 3 and the current pre-amplifying circuit 4 for coupling and amplifying the current signal of the deep side main current and the current signal of the shallow side main current, respectively.
Further, the DSP interface circuit 6 includes a filtering unit 81 and an operation unit 82, wherein the filtering unit 81 IS configured to perform filtering processing on the digital voltage signal and the digital current signal, and the operation unit 82 IS configured to perform discrete fourier transform on the filtered digital voltage signal and the filtered digital current signal to obtain a deep lateral voltage signal amplitude VD, a shallow lateral voltage signal amplitude VS, a deep lateral current signal amplitude ID, and a shallow lateral current signal amplitude IS.
It should be noted that the filtering unit 81 and the arithmetic unit 82 in this embodiment may be any filter or calculation module suitable for this embodiment, and are not limited here.
Further, the DSP interface circuit 6 is further provided with a bus interface 83, and the bus interface 83 is connected to the remote control system 9 and is used for data interaction with the remote control system 9. Specifically, the connection between the bus interface 83 and the remote control system 9 may be wired by a cable or wirelessly by wireless means to transmit the obtained deep side voltage signal amplitude VD, shallow side voltage signal amplitude VS, deep side current signal amplitude ID, and shallow side current signal amplitude IS to the remote control system 9 or to send instructions from the remote control system 9 to the DSP interface circuit 6.
The utility model discloses a petroleum formation resistivity measuring instrument's operating frequency signal processing circuit can effectively reduce analog circuit's device quantity to reduce the power consumption. The working frequency signal processing circuit adopts the DSP interface circuit to perform data processing and operation, compared with the traditional microprocessor circuit, the DSP interface circuit has high operation speed and high obtained data precision.
The foregoing is a more detailed description of the present invention, taken in conjunction with the specific preferred embodiments thereof, and it is not intended that the invention be limited to the specific embodiments shown and described. To the utility model belongs to the technical field of ordinary technical personnel, do not deviate from the utility model discloses under the prerequisite of design, can also make a plurality of simple deductions or replacement, all should regard as belonging to the utility model discloses a protection scope.
Claims (8)
1. The working frequency signal processing circuit of the petroleum formation resistivity measuring instrument is characterized by comprising a voltage mixing signal circuit (1), a voltage preamplification circuit (2), a current mixing signal circuit (3), a current preamplification circuit (4), a multi-channel analog-to-digital converter circuit (5) and a DSP interface circuit (6),
the voltage mixing signal circuit (1) is connected with the voltage pre-amplifying circuit (2) and is used for acquiring original mixing voltage signals of a shallow side main current and a deep side main current of the petroleum formation resistivity measuring instrument and transmitting the original mixing voltage signals to the voltage pre-amplifying circuit (2);
the voltage pre-amplification circuit (2) is connected with the multi-channel analog-to-digital converter circuit (5);
the current mixing signal circuit (3) is connected to the current preamplification circuit (4) and is used for acquiring original mixing current signals of a shallow side main current and a deep side main current of the petroleum formation resistivity measuring instrument and transmitting the signals to the current preamplification circuit (4);
the current preamplification circuit (4) is connected with the multi-channel analog-to-digital converter circuit (5);
the multichannel analog-to-digital converter circuit (5) can input a first square wave signal (7) and a second square wave signal (8) and is used for performing chopping and analog-to-digital conversion on the processed mixed voltage signal and the processed mixed current signal through the first square wave signal (7) and the second square wave signal (8) respectively to obtain a digital voltage signal and a digital current signal;
the DSP interface circuit (6) is connected with the multi-channel analog-to-digital converter circuit (5) and is used for obtaining the amplitude of a deep lateral voltage signal, the amplitude of a shallow lateral voltage signal, the amplitude of a deep lateral current signal and the amplitude of a shallow lateral current signal and generating a deep lateral power control signal and a shallow lateral power control signal.
2. The operating frequency signal processing circuit of the petroleum formation resistivity measuring instrument according to claim 1, further comprising a voltage amplification coupling transformer (T1) connected between the voltage mixing signal circuit (1) and the voltage pre-amplifying circuit (2).
3. The operating frequency signal processing circuit of the petroleum formation resistivity measuring instrument according to claim 1, further comprising a current amplifying coupling transformer (T2) connected between the current mixing signal circuit (3) and the current pre-amplifying circuit (4).
4. The operating frequency signal processing circuit of the oil formation resistivity measuring instrument according to claim 1, wherein the DSP interface circuit (6) includes a filtering unit (81) and an operation unit (82), wherein the filtering unit (81) is configured to perform filtering processing on the digital voltage signal and the digital current signal, and the operation unit (82) is configured to perform discrete Fourier transform on the filtered digital voltage signal and the filtered digital current signal to obtain a deep lateral voltage signal amplitude, a shallow lateral voltage signal amplitude, a deep lateral current signal amplitude and a shallow lateral current signal amplitude.
5. The operating frequency signal processing circuit of the oil formation resistivity measuring instrument according to claim 1, wherein the first square wave signal (7) is a 35Hz square wave signal.
6. The operating frequency signal processing circuit of the oil formation resistivity measuring instrument according to claim 5, wherein the second square wave signal (8) is a 280Hz square wave signal.
7. The operating frequency signal processing circuit of the oil formation resistivity measuring instrument according to claim 1, wherein the multi-channel analog-to-digital converter circuit (5) is a six-channel analog-to-digital converter circuit.
8. The operating frequency signal processing circuit of the oil formation resistivity measuring instrument according to any one of claims 1 to 7, wherein the DSP interface circuit (6) is further provided with a bus interface (83), and the bus interface (83) is connected with a remote control system (9).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020647820.0U CN212031351U (en) | 2020-04-24 | 2020-04-24 | Working frequency signal processing circuit of petroleum formation resistivity measuring instrument |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020647820.0U CN212031351U (en) | 2020-04-24 | 2020-04-24 | Working frequency signal processing circuit of petroleum formation resistivity measuring instrument |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN212031351U true CN212031351U (en) | 2020-11-27 |
Family
ID=73497076
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202020647820.0U Active CN212031351U (en) | 2020-04-24 | 2020-04-24 | Working frequency signal processing circuit of petroleum formation resistivity measuring instrument |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN212031351U (en) |
-
2020
- 2020-04-24 CN CN202020647820.0U patent/CN212031351U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109001997B (en) | Anti-interference environment information acquisition system | |
| CN203572874U (en) | Detection detection device and current detection chip | |
| CN212031351U (en) | Working frequency signal processing circuit of petroleum formation resistivity measuring instrument | |
| CN201477423U (en) | Intelligent vibration monitoring and protecting apparatus | |
| CN110488065A (en) | A kind of high-voltage signal acquisition system based on optical fiber transmission | |
| CN210745091U (en) | Signal acquisition circuit | |
| CN111366613A (en) | Working frequency signal processing circuit of petroleum formation resistivity measuring instrument | |
| CN105445535A (en) | Digital current transducer and detection device | |
| CN106645590B (en) | Gas concentration measuring device based on differential acquisition | |
| CN204272046U (en) | A kind of biological Detection of Weak Signals and treatment circuit | |
| CN114966118A (en) | XCP probe electrode channel noise measuring device in rotation state | |
| CN205483247U (en) | Ultrasonic wave collection system based on optic fibre EFPI sensor | |
| CN213846616U (en) | Measuring amplifier for audio signal measurement | |
| CN202166628U (en) | Remote multi-channel wireless chemical oxygen demand (COD) detection alarming system based on capacitive sensor | |
| CN209784791U (en) | Sensing data acquisition and processing system | |
| CN208060013U (en) | A kind of environment noise test device | |
| CN103654766A (en) | Low-override amplification device for weak physiological signals | |
| CN205262915U (en) | PM2. 5 sensor based on infrared ray photoelectric conversion | |
| CN201885804U (en) | Double-wavelength infrared flame detector | |
| CN111436916A (en) | Analog front-end chip architecture for wearable three-dimensional pulse wave monitoring | |
| CN203749406U (en) | Weak-physiological-signal low-magnification amplification device | |
| CN105222700A (en) | Based on the digital strainometer of DSP and FPGA | |
| CN203479420U (en) | Transformer multipath temperature monitoring system | |
| CN203705665U (en) | Voice/vibration signal identification system | |
| CN210513245U (en) | Temperature and humidity transmitter and monitoring system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |