RU2533759C1 - Apparatus for measuring spectral characteristics of geoacoustic noise in well - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: apparatus for measuring spectral characteristics of geoacoustic noise in a well comprising, in a downhole tool, three mutually orthogonal geoacoustic signal sensors, a sensor switch, an amplifier, a microcontroller with a built-in high-speed analogue-to-digital converter, a temperature sensor for immediate correction of measurement results, a self-contained power supply unit, a supply voltage control unit, an SD card for storing obtained information, an SD card switch for facilitating switching of operating modes on SPI and MMC protocols, a unit for interfacing with a personal computer on a COM protocol for setting up operating parameters of the apparatus, a unit for interfacing with a personal computer on an MMC-USB protocol for transmitting measurement data.

EFFECT: use of a high-speed analogue-to-digital converter built into a microcontroller and an SD card to store results enables to obtain a volume of measurements which is sufficient for analysis with high accuracy through spectral characteristics using three-component geoacoustic logging techniques.

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Description

The invention relates to geophysics and can be used to measure geoacoustic noise in various frequency bands, in particular for measuring the spectral characteristics of the components of the vector of a natural geoacoustic signal in the well.

A device for measuring geo-acoustic noise in a well (RU 2123711), comprising three mutually orthogonal sensors of geo-acoustic signals, a sensor switch, a filter unit, a rectifier unit, a second switch, an analog-to-digital converter, a transmit-receive unit, are connected in series and connected to the amplifier output connected to the logging cable, as well as two gravitational accelerometers, the outputs of which are connected to the inputs of the second switch, fortified in such a way that their sensitivity axes coincide direction with the axes of sensitivity of the two sensors geoacoustic signals directed perpendicularly to the downhole tool axis.

A device for conducting geo-acoustic logging (RU 2445653) is also known, which contains three mutually orthogonal sensors for geo-acoustic signals, an amplifier, switches, an analog-to-digital converter and a block of bandpass filters.

The disadvantage of the above devices is the use of a logging cable to connect the measuring device to a power source and transfer measurement data for subsequent processing. This drawback makes it difficult to use these devices in wells with an aggressive environment (for example, when used in fields with a high content of hydrogen sulfide in the well). In addition, the above instruments use band-pass filters, which do not allow measurements with increased accuracy.

The objective of the invention is the creation of an autonomous device for conducting geoacoustic studies with increased accuracy.

The proposed device contains three mutually orthogonal sensors of geoacoustic signals, a sensor switch, an amplifier, a microcontroller with a built-in high-speed analog-to-digital converter for measuring the spectral characteristics of a natural noise signal, an SD card for storing the received information, an SD card switch for the ability to switch operating modes using SPI and MMS, temperature sensor, power supply, voltage control unit for batteries, PC interface with a personal computer COM protocol for adjusting the operation parameters of the device, a unit for interfacing with a personal computer via MMC-USB protocol for transmitting measurement data.

The drawing (figure 1) shows a functional diagram of the device.

The device contains: 1, 2, 3 - three mutually orthogonal sensors of geoacoustic signals ZN, XN, YN, the sensitivity axis of one of them ZN is directed along the axis of the downhole tool, and the other two - XN, YN - perpendicular to the axis of the device, 4 - sensor switch, 5 - a signal amplifier, 6 - a microcontroller with a built-in high-speed analog-to-digital converter, 7 - a supply voltage control unit, 8 - a power supply unit, 9 - a temperature sensor, 10 - a unit for interfacing with a personal computer using the COM protocol to configure device operation parameters, 11 - comm SD card trimmer, 12 - SD card, 13 - PC interface using MMC-USB protocol for transferring measurement data.

The device operates as follows.

Before starting the measurements, using the unit 10 for interfacing with a personal computer (not shown in the diagram), the COM parameters of the device are adjusted using the COM protocol (cleaning non-volatile memory from the results of previous measurements, setting the real-time clock, setting the start time of measurements, duration of measurements, sampling period, determining the accuracy of measurements, setting the SD card mode, etc.). When conducting measurements, the signal value from each of the sensors 1, 2, 3 through the switch 4, controlled by the microcontroller 6, and the amplifier 5 enters the microcontroller 6, where they are digitized at a given frequency on the built-in high-speed analog-to-digital converter (not shown) discretization. Then, the obtained measurement results using the SPI bus are stored on the SD card 12. The signal of the temperature sensor 9 also enters the microcontroller 6, is processed and stored on the SD card 12. To provide power to the device, an autonomous power supply unit 8 is used, which contains replaceable batteries and a voltage regulator (not shown in the diagram). To monitor the condition of the batteries, the power supply control unit 7, controlled by the microcontroller 6, is used. After measurements, the device is connected to the personal computer (not shown) in the interface unit 13 via USB protocol for further processing of the measurement results. At the same time, the SD card switch 11 sets it to high-speed data transfer mode using the MMS protocol.

Using a high-speed analog-to-digital converter and an SD card built into the microcontroller to save the results allows us to obtain a measurement volume sufficient for analysis with increased accuracy using spectral characteristics using a three-component geoacoustic logging technique.

Claims (1)

A device for measuring the spectral characteristics of geo-acoustic noise in a well, comprising three mutually orthogonal sensors of geo-acoustic signals in the well, a sensor switch, an amplifier, characterized in that it further comprises a microcontroller with a built-in high-speed analog-to-digital converter, a temperature sensor designed to directly correct the measurement results , autonomous power supply unit, power voltage control unit, SD card for storing received information AI, an SD card switch for the ability to switch operating modes using the SPI and MMS protocols, a PC interface unit for using the COM protocol to configure device operation parameters, an interface unit with a personal computer for MMC-USB protocol for transmitting measurement data.