A high-power well-ground-well integrated intelligent combined observation system and method

Abstract

The application discloses a kind of high-power well-ground-ground well integration intelligent combined observation system and method, belong to physical exploration technical field;The system includes central control module, distributed acquisition module and mode switching module;Central control module is used to parse exploration task and generates observation mode instruction;Distributed acquisition module includes multiple ground receiving terminals and multiple downhole receiving terminals, and each terminal calculates local signal-to-noise ratio in real time and reports;Mode switching module is controlled to execute the physical switching of well-ground mode and ground well mode;The method is based on the cooperation of the above module, through each terminal real-time reporting signal-to-noise ratio, central control module carries out data fusion and calculates global signal-to-noise ratio, when global signal-to-noise ratio is lower than preset threshold, automatically generate switching instruction to drive mode switching;The application solves the problem that observation mode is fixed, manual switching lags behind, data quality cannot be evaluated in real time in the prior art, realizes the intelligent quality control of exploration operation.

Description

Technical Field

[0001] This invention relates to the field of geophysical exploration technology, specifically a high-power well-to-ground integrated intelligent joint observation system and method. Background Technology

[0002] High-power electrical resistivity tomography (EPT) is an important method for deep mineral resource exploration. It is mainly divided into two observation methods: borehole-to-surface transmission and surface transmission-to-bottom transmission. The borehole-to-surface mode has high sensitivity for detecting weak signals in deep areas, while the surface-to-bore mode has a wide lateral coverage. The two modes are complementary, and joint observation can obtain more accurate information on underground electrical structure.

[0003] However, existing technologies have the following drawbacks: First, the observation mode is fixed and lacks adaptive adjustment capabilities. Existing systems typically determine whether to use a well-to-surface mode or a surface-to-well mode before operation and maintain this mode during the acquisition process. Due to the unknown underground geological conditions and the time-varying nature of environmental disturbances, the pre-set single mode often fails to adapt to actual working conditions, resulting in a large amount of invalid data acquisition and a high rework rate. Secondly, mode switching relies on human experience and has a serious response lag; although a few systems have two modes at the same time, mode switching requires manual power off, disconnection and reconnection of high-voltage cables, and resetting of parameters, which takes several hours; operators can only discover data quality problems after data collection is completed and indoor processing is completed, and cannot intervene on-site in real time, often missing the best time for supplementary data collection. Secondly, there is a lack of distributed architecture and real-time data fusion mechanism; the ground receiving stations and downhole probes of the existing system are mostly independent devices, lacking a unified control network and data interaction, making it impossible to obtain the data quality status of all terminals in real time, let alone make decisions based on a global perspective; Finally, there is a lack of closed-loop control based on real-time signal-to-noise ratio feedback; the existing system cannot evaluate the signal-to-noise ratio of the collected data in real time, nor can it automatically adjust the observation strategy based on the evaluation results. Operators can only blindly collect data and wait for the processing results.

[0004] To address the aforementioned issues, this invention proposes a high-power well-to-ground integrated intelligent joint observation system and method. By constructing a collaborative architecture consisting of a central control module, a distributed acquisition module, and a mode switching module, it achieves real-time signal-to-noise ratio monitoring and adaptive mode switching across multiple terminals. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies, such as fixed observation modes, delayed manual switching, inability to assess data quality in real time, and lack of distributed real-time monitoring mechanisms. It provides a high-power well-to-ground integrated intelligent joint observation system and method, which achieves closed-loop intelligent control and proactive intervention throughout the entire process from exploration task analysis, data acquisition, quality assessment to mode switching through deep collaboration of task-driven, multi-node real-time signal-to-noise ratio monitoring and adaptive mode switching, and intelligent decision-making by integrating multi-source data fusion and digital twin simulation.

[0006] This application provides a high-power well-to-ground integrated intelligent joint observation system, including a central control module, a distributed acquisition module, and a mode switching module; The central control module is used to interface with the external exploration task management system, receive and parse the exploration task data stream, generate observation mode execution instructions with unique identifiers, the instructions include target geological body information and corresponding expected signal-to-noise ratio requirements; and receive the local signal-to-noise ratios reported in real time by the surface receiving terminals and downhole receiving terminals in the distributed acquisition module, perform multi-source data fusion on the local signal-to-noise ratios reported by each terminal and calculate the global signal-to-noise ratio under the current observation mode. When the global signal-to-noise ratio does not meet the expected signal-to-noise ratio requirements, based on the target geological body information and the switching effect evaluation of the geological characteristics of the work area, it automatically decides whether to execute the observation mode switch. The distributed acquisition module is communicatively connected to the central control module and includes a ground receiving terminal and an underground receiving terminal. Both the ground receiving terminal and the underground receiving terminal have built-in local controllers and signal-to-noise ratio calculation units, which are used to synchronously acquire electric field and magnetic field response data when the high-power transmitter supplies current to the ground, and calculate the local signal-to-noise ratio based on the response data and report it to the central control module. The mode switching module is connected to the central control module and the high-power transmitter, and is controlled by the central control module. It is used to perform physical switching between well-to-ground mode and well-to-ground mode when it receives a mode switching command issued by the central control module. Well-to-ground mode is an observation mode of downhole transmission and ground reception, and well-to-ground mode is an observation mode of ground transmission and downhole reception. The central control module is also used to control the mode switching module to perform the switching after generating the mode switching instruction, and to notify each terminal in the distributed acquisition module to automatically load the preset working parameters of the new mode after the switching and continue data acquisition.

[0007] Furthermore, the central control module includes a task parsing unit, a data fusion unit, and a status decision unit; The task parsing unit is configured to receive exploration task data streams from the exploration task management system, parse and extract key fields such as target geological body information, observation frequency band, transmission power, planned execution time and corresponding expected signal-to-noise ratio requirements from the exploration task data streams, and generate initial observation mode execution instructions. The data fusion unit is configured to receive local signal-to-noise ratio data reported in real time by all ground receiving terminals and downhole receiving terminals, and calculate the global signal-to-noise ratio under the current observation mode through a multi-source data fusion algorithm. The state decision unit is configured to maintain the state machine of the observation task; the state machine includes the states of task creation, pending execution, execution, pending switching, and completed; the unit is further configured to: listen to the local signal-to-noise ratio (SNR) reported data from the distributed acquisition module and the global SNR calculation result from the data fusion unit, compare the global SNR with the expected SNR requirement in the instruction, trigger a mode switching evaluation when the global SNR does not meet the expected SNR requirement, and drive the state switching according to a predefined state-event mapping rule, the state-event mapping rule defines the next state to switch to and the action to be performed when a specific event occurs in the current state, the specific event includes one of the following: the planned execution time arrives, the switching completion is confirmed, or all preset acquisition quantities are completed, and store the event log for each state switching, the event log includes the state identifier before and after the state switching, the triggering event, and the timestamp; The state decision unit is also used to receive fault warnings reported by the mode switching module. The fault warnings include relay contact failure warnings, current zero-crossing detection failure warnings, and power recovery abnormality warnings. The unit then performs corresponding processing according to the predefined mapping relationship between fault types and processing measures. The processing measures include recording fault information, pausing the switching operation, automatically retrying the switching, and triggering an emergency shutdown.

[0008] Specifically, the process of maintaining the state machine for the observation task includes: When the task parsing unit generates a complete initial observation mode execution instruction, the initial state of the observation task is set to pending execution. When the planned execution time of the observation task reaches the predefined execution window, the task status is switched from pending execution to execution, and the distributed acquisition module is notified to start data acquisition. When the mode switching conditions determined by the preset decision logic are met, the task status is switched from executing to pending switching. If a switch occurs, after receiving a switch completion confirmation signal from the switch drive unit of the mode switch module, and after the central control module verifies the switch success based on the status monitoring data carried in the signal, the task status is switched from pending switch back to execution, and data acquisition continues. When all the preset data collection for the observation task is completed, the task status will be switched to "completed". Specifically, the process of comparing the global signal-to-noise ratio (SNR) with the expected SNR requirement in the instruction, and triggering a mode-switching evaluation when the global SNR does not meet the expected SNR requirement, includes: Preset global signal-to-noise ratio low threshold, duration threshold, and expected gain threshold; When the global signal-to-noise ratio is lower than the low threshold and the duration exceeds the duration threshold, it is confirmed that the expected signal-to-noise ratio requirement has not been met, and a mode switching evaluation is triggered. The geological features and theoretical models of the work area are retrieved from the historical database. A real-time geological model is updated based on the currently collected measured data. The real-time geological model is then input into a digital twin simulation engine for forward modeling to obtain electromagnetic field response data when switching to another observation mode. The expected global signal-to-noise ratio is then calculated based on the response data and the current environmental noise level. Calculate the expected gain, which is the difference between the expected global signal-to-noise ratio and the global signal-to-noise ratio under the current observation mode; If the expected gain exceeds the expected gain threshold, a mode switching instruction is generated to switch the task status from executing to pending switching. If the expected gain does not exceed the expected gain threshold, the current mode is maintained, but a parameter adjustment instruction is broadcast to each terminal in the distributed acquisition module to adjust the transmission frequency and receiving gain to adapt to the current interference environment. Furthermore, the distributed acquisition module includes a ground receiving array and a string of downhole probes; The ground receiving array consists of multiple ground receiving terminals. Each ground receiving terminal is connected to the central control module via an industrial Ethernet and has a built-in local controller, GNSS timing module, high-precision ADC converter, and FPGA edge computing unit. The GNSS timing module is used to provide a unified time reference for data acquisition. The high-precision ADC converter is used to convert analog electric and magnetic field signals into digital signals. The FPGA edge computing unit is used to perform filtering, Fourier transform, and local signal-to-noise ratio calculation on the digital signals. The local controller is used to coordinate the work of each module and report the calculation results. The downhole probe string consists of multiple downhole receiving terminals connected in series. Each downhole receiving terminal is connected to the central control module via a power line carrier bus and has a built-in local controller, high-precision temperature-compensated crystal oscillator and signal conditioning circuit, which is used to collect downhole electric and magnetic field response data in real time and calculate the local signal-to-noise ratio. The power line carrier bus utilizes the core of the armored cable as the transmission medium, simultaneously supplying power to the downhole receiving terminal and transmitting data.

[0009] Specifically, after receiving a mode switching command from the central control module, the local controller of each of the ground receiving terminals and downhole receiving terminals automatically performs the following operations: Save the current working parameters to the local cache; Based on the preset parameter table of the target mode, load the corresponding sampling rate, gain coefficient and filtering frequency; Re-establish clock synchronization with the central control module; The system enters a new data acquisition state and reports its readiness status to the central control module. The readiness status includes confirmation of successful parameter loading, clock synchronization deviation value, and hardware self-test normal status. The automatic execution process is completed within a preset time after receiving the mode switching command, ensuring the continuity and comparability of the collected data.

[0010] Furthermore, the mode switching module includes a high-pressure switching matrix unit, a switching drive unit, and a ground-based transmitting electrode and a downhole transmitting electrode; The high-voltage switching matrix unit consists of multiple vacuum high-voltage relays, used to selectively connect the output terminal of the high-power transmitter to the ground transmitting electrode and the downhole transmitting electrode; The switching drive unit is connected to the digital output terminal of the central control module. After receiving the mode switching command, it performs the following operations in sequence according to the preset timing logic: sending a power reduction command to the high-power transmitter, delaying and waiting for the current to cross zero, driving the high-voltage switching matrix to perform physical switching, and sending a power recovery command to the high-power transmitter. The switching drive unit also has a built-in status monitoring circuit to detect the contact status of each relay in the switching matrix in real time, and to report a fault warning to the central control module when an abnormality is detected. The ground-based transmitting electrode is deployed on the surface and is used to supply current underground in well mode; the downhole transmitting electrode is installed on an armored cable and can be lowered into the well, and is used to supply current underground in well-to-ground mode.

[0011] Furthermore, the high-power well-to-ground integrated intelligent joint observation method is characterized by comprising the following steps: The central control module connects to the exploration task management system, parses the exploration task data stream, and generates observation mode execution instructions with unique identifiers. The instructions include target geological body information, observation frequency band, transmission power, planned execution time, and corresponding expected signal-to-noise ratio requirements. The ground receiving terminal and the downhole receiving terminal in the distributed acquisition module acquire data according to the initial observation mode. Each terminal calculates the local signal-to-noise ratio in real time and periodically reports it to the central control module. The central control module performs multi-source data fusion on the local signal-to-noise ratios reported by all terminals and calculates the global signal-to-noise ratio under the current observation mode; The central control module compares the global signal-to-noise ratio with the expected signal-to-noise ratio requirement. When the global signal-to-noise ratio does not meet the expected signal-to-noise ratio requirement, it automatically decides whether to perform the observation mode switch based on the target geological body information and the switching effect evaluation of the geological characteristics of the work area. If the decision is made to perform the switch, a mode switching command is generated. The central control module sends a mode switching command to the mode switching module, driving the mode switching module to perform a physical switch between well-to-ground mode and ground-to-well mode; After the switch is completed, each terminal in the distributed acquisition module automatically loads the preset parameters of the new mode, continues data acquisition, and repeats the above steps until the exploration task is completed.

[0012] Specifically, the central control module compares the global signal-to-noise ratio (SNR) with the expected SNR requirement. When the global SNR does not meet the expected SNR requirement, it automatically decides whether to switch the observation mode based on the target geological body information and the evaluation of the switching effect of the geological characteristics of the work area. This includes: The central control module's state decision unit receives the global signal-to-noise ratio calculated by the data fusion unit in real time; compares the global signal-to-noise ratio with a preset low threshold for global signal-to-noise ratio, and monitors the duration of the value being below the threshold. When the global signal-to-noise ratio is lower than the low threshold and the duration exceeds the set value, it is confirmed that the expected signal-to-noise ratio requirement is not met, and the mode switching evaluation process is triggered. The state decision unit retrieves the geological features and theoretical models of the work area from the historical database, updates the real-time geological model based on the currently collected measured data, inputs the real-time geological model into the digital twin simulation engine for forward modeling, obtains the electromagnetic field response data when switching to another observation mode, and calculates the expected global signal-to-noise ratio based on the response data and the current environmental noise level. Obtain the current global signal-to-noise ratio calculated by the data fusion unit, calculate the expected gain, which is the difference between the expected global signal-to-noise ratio and the current global signal-to-noise ratio, and compare the expected gain with a preset gain threshold. If the expected gain exceeds the preset gain threshold, a mode switching instruction is generated, and the observation task status is switched from executing to pending switching. If the expected gain does not exceed the preset gain threshold, the current mode is maintained, but a parameter adjustment instruction is broadcast to each terminal in the distributed acquisition module to adjust the transmission frequency and the receiving gain.

[0013] Furthermore, the method also includes a full-process traceability management step: The status decision unit of the central control module records the local signal-to-noise ratio data reported by all ground receiving terminals and downhole receiving terminals in real time; Record the global signal-to-noise ratio time series calculated by the data fusion unit; Record the generation time, triggering reason, and expected gain value of each mode switching command; Record the start and end times, switching results, and status monitoring data of the mode switching module. Record the parameter loading status and ready time of each terminal in the distributed acquisition module after mode switching; All recorded data are associated and stored according to a unique identifier to form a full-process traceable management log containing all recorded data, which is used for post-event analysis, quality assessment and system optimization.

[0014] The beneficial effects of this invention are as follows: This invention constructs a closed-loop intelligent control system centered on task-driven, real-time signal-to-noise ratio (SNR) monitoring, and adaptive mode switching through the collaboration of a central control module, a distributed acquisition module, and a mode switching module. This solves the problems of fixed observation modes, delayed manual switching, and the inability to assess data quality in real time in existing technologies. Through the multi-level decision-making logic built into the central control module, it combines global SNR threshold comparison, duration judgment, and expected gain assessment, and uses digital twin simulation technology to predict switching effects, achieving intelligent decision-making and precise execution of observation mode switching, thus improving the success rate of acquiring deep, weak signals. The automatic parameter adjustment mechanism of each terminal in the distributed acquisition module after receiving a mode switching command ensures the continuity and comparability of acquired data before and after mode switching. The real-time recording and associated storage of data throughout the entire process by the central control module forms a complete traceable management log, achieving a technological leap from blind acquisition post-processing to in-process quality interception. Attached Figure Description

[0015] To better understand and implement this application, the technical solution is described in detail below with reference to the accompanying drawings.

[0016] Figure 1 This is a schematic diagram of the overall architecture of the system of the present invention; Figure 2 This is a flowchart of the mode switching decision-making process based on signal-to-noise ratio evaluation in this invention. Figure 3 This is a flowchart of the overall process of the method of the present invention. Detailed Implementation

[0017] To further illustrate the technical means and effects adopted by the present invention to achieve its intended purpose, exemplary embodiments will be described in detail below, examples of which are illustrated in the accompanying drawings. In the following description, when referring to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application.

[0018] The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The singular forms “a,” “the,” and “the” used herein are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

[0019] The following detailed description of the specific implementation methods, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided in detail.

[0020] Example 1 Please see Figures 1-2 This embodiment provides a high-power well-to-ground integrated intelligent joint observation system, including a central control module, a distributed acquisition module, and a mode switching module; The central control module is used to interface with the external exploration task management system, receive and parse the exploration task data stream, and generate an observation mode execution command with a unique identifier. The command includes the target geological body information and the corresponding expected signal-to-noise ratio requirement. The central control module also performs multi-source data fusion and calculates the global signal-to-noise ratio based on the local signal-to-noise ratio reported by the distributed acquisition module. When the global signal-to-noise ratio does not meet the expected signal-to-noise ratio requirement, it automatically decides whether to switch the observation mode based on the target geological body information and the switching effect evaluation of the geological characteristics of the work area. The distributed acquisition module is communicatively connected to the central control module and includes a ground receiving terminal and a downhole receiving terminal. Both the ground receiving terminal and the downhole receiving terminal have built-in local controllers and signal-to-noise ratio calculation units, which are used to calculate the local signal-to-noise ratio in real time during data acquisition and report it to the central control module. The mode switching module is connected to the central control module and the high-power transmitter, and is controlled by the central control module. It is used to perform physical switching between well-to-ground mode and well-to-ground mode when it receives a mode switching command issued by the central control module. Furthermore, the central control module includes a task parsing unit, a data fusion unit, and a status decision unit; The task parsing unit is configured to receive exploration task data streams from the exploration task management system, parse and extract key fields such as target geological body information, observation frequency band, transmission power, planned execution time and corresponding expected signal-to-noise ratio requirements from the exploration task data streams, and generate initial observation mode execution instructions. The process of generating the initial observation mode execution command specifically includes: the task parsing unit first establishes a connection with the external exploration task management system through a preset communication protocol, and listens for and acquires the newly issued exploration task data stream in real time; for the received task data, the task parsing unit uses a rule-based information extraction algorithm to identify and extract key fields from the structured or semi-structured task description text; specifically, through keyword matching and context analysis, it extracts information about the target geological body, such as the spatial location coordinates and depth range; it extracts observation frequency band and transmission power parameters such as the observation method type, working frequency range, and transmission current intensity; it extracts planned execution time information such as the task start time, end time, and acquisition duration at each measuring point; finally, the task parsing unit assigns a globally unique task sequence number to the extracted information, assembles it into a structured initial observation mode execution command, and sends it to the state decision unit for subsequent state management; The data fusion unit is configured to receive local signal-to-noise ratio data reported in real time by all ground receiving terminals and downhole receiving terminals, and calculate the global signal-to-noise ratio under the current observation mode through a multi-source data fusion algorithm. The process of calculating the global signal-to-noise ratio (SNR) under the current observation mode using a multi-source data fusion algorithm specifically includes: First, the data fusion unit establishes communication links with all ground-based and downhole receiving terminals. Each terminal periodically reports its calculated local SNR value at a preset frequency. After receiving these reported data, the data fusion unit first performs data cleaning to remove obviously abnormal values. Subsequently, a weighted average fusion algorithm is used to calculate the global SNR. The specific calculation formula is as follows: ;in, For the first The local signal-to-noise ratio reported by each ground receiving terminal The corresponding weighting coefficients are dynamically adjusted based on factors such as the terminal's geographical location and the reliability of historical data. For the first The local signal-to-noise ratio reported by each downhole receiving terminal The corresponding weighting coefficients are dynamically adjusted based on factors such as the probe's depth and distance from the target geological body. This represents the total number of ground receiving terminals. The total number of downhole receiving terminals; through this weighted fusion method, the data collected by all terminals are fully considered, while the contribution of terminals in key locations is highlighted, so that the calculated global signal-to-noise ratio can more accurately reflect the overall data quality under the current observation mode; The state decision unit is configured to maintain the state machine of the observation task. The state machine includes states of task creation, pending execution, execution, pending switching, and completed. The unit is further configured to: monitor local signal-to-noise ratio (SNR) reported data from the distributed acquisition module and global SNR calculation results from the data fusion unit; compare the global SNR with the expected SNR requirement in the instruction; trigger mode switching evaluation when the global SNR does not meet the expected SNR requirement; and drive state switching according to predefined state-event mapping rules. The state-event mapping rules define the next state to switch to and the action to be performed when a specific event occurs in the current state. The specific event includes the arrival of the planned execution time, confirmation of switching completion, or completion of all preset acquisition quantities. The unit also stores an event log for each state switch, which includes the state identifier before and after the state switch, the triggering event, and a timestamp. The state decision unit is also used to receive fault warnings reported by the mode switching module and perform corresponding processing according to predefined fault handling rules. The process of comparing the global signal-to-noise ratio (SNR) with the expected SNR requirement involves the specific setting method of the expected SNR requirement. The expected SNR requirement can be achieved through preset thresholds, such as a low global SNR threshold and a duration threshold. The low global SNR threshold is an empirical value, set comprehensively based on historical data of the work area, environmental noise levels, and the data quality requirements of the exploration target; it typically ranges from 10 to 30 dB. When the global SNR is lower than this threshold, it indicates that the quality of the currently acquired data may not meet exploration needs. The duration threshold is used to prevent misjudgments caused by transient interference and is typically set to 3-5 consecutive sampling periods. Only when the global SNR remains below the low threshold for a period exceeding the duration threshold does the system determine that the expected SNR requirement has not been met and a mode switching evaluation needs to be triggered. The predefined state-event mapping rules are the core control logic of the state decision unit. Based on state machine theory, these rules define the system's response actions to various triggering events under different states. Specifically, the state-event mapping rules are stored in the state decision unit in tabular form, with each row defining the next state and execution action corresponding to a current state-triggering event combination. For example, the rules can be defined as follows: when the current state is pending execution and the triggering event is the arrival of the planned execution time, the next state switches to "in execution," and the execution action is to notify the distributed acquisition module to start data acquisition; when the current state is in execution and the triggering event is a global signal-to-noise ratio below the threshold and a duration exceeding the limit, the next state switches to "pending switching," and the execution action is to trigger the mode switching evaluation process; when the current state is pending switching and the triggering event is an expected gain exceeding the threshold, the next state switches to "in execution," and the execution action is to generate a mode switching command and send it to the mode switching module; when the current state is pending switching and the triggering event is an expected gain not exceeding the threshold, the next state remains "in execution," and the execution action is to broadcast a parameter adjustment command to the terminal. Through these state-event mapping rules, the state decision unit achieves automated and intelligent management of the entire lifecycle of the observation task. The predefined fault handling rules serve as the basis for the state decision unit to respond to fault warnings reported by the mode switching module. These rules are also stored in a rule table, defining the handling measures corresponding to different types of fault warnings. For example, when a relay contact failure fault warning is received, the rule is defined as: record the fault information to the event log, send an alarm notification to the central control module, suspend the current mode switching operation, revert the task state to the previous stable state, and wait for manual intervention. When a current zero-crossing detection failure fault warning is received, the rule is defined as: record the fault information, automatically retry the switching operation three times, and if it still fails... The switching process is paused and reported for manual handling. When a power recovery anomaly fault warning is received, the rule is defined as: immediately disconnecting the transmitter output, recording the fault information, triggering the system emergency shutdown procedure, and notifying the operator for on-site inspection. Through this set of fault handling rules, the system can automatically take corresponding protective measures when an anomaly occurs to ensure the safety of equipment and personnel, while providing detailed data support for subsequent fault troubleshooting. The fault warnings include relay contact failure warnings, current zero-crossing detection failure warnings, and power recovery anomaly warnings. The handling measures include recording fault information, pausing the switching operation, automatically retrying the switching, and triggering an emergency shutdown.

[0021] Furthermore, during the operation of the system, when the mode switching conditions determined by the preset decision logic are met, the state decision unit switches the task state from execution to pending switching and triggers the subsequent switching evaluation process. The preset decision logic is the core algorithm for determining whether to perform a mode switch. This decision logic employs a multi-level judgment mechanism, specifically including three levels: threshold comparison, duration judgment, and expected gain evaluation. First, the decision logic compares the current global signal-to-noise ratio (SNR) with a preset low threshold for global SNR. Second, when the global SNR is below the low threshold, it further determines whether the duration below the threshold exceeds a preset duration threshold. Finally, when both of the above conditions are met, the mode switch evaluation process is triggered. The expected gain for switching to another observation mode is calculated through digital twin simulation, and the expected gain is compared with a preset gain threshold. Only when the expected gain exceeds the gain threshold is the mode switch finally executed. This multi-level decision logic effectively avoids erroneous switching caused by transient interference or local noise, ensuring that each mode switch brings actual data quality improvement. The decision-making logic involves setting multiple preset thresholds, including a preset low global signal-to-noise ratio (SNR) threshold, a duration threshold, and an expected gain threshold. The low SNR threshold takes into account factors such as the ambient noise level of the work area, the depth of the target geological body, and the transmission power. It is typically calculated automatically by the system based on historical data or manually set by the operator according to the exploration task requirements, with a value generally ranging from 15-25 dB. The duration threshold is related to the data acquisition sampling period, typically 3-5 sampling periods. For example, when the sampling period is 1 second, the duration threshold can be set to 3-5 seconds, avoiding the impact of instantaneous interference while ensuring timely response to data quality degradation. The expected gain threshold reflects the system's expectation of the mode switching effect, typically set to 3-6 dB. Switching is considered valuable only if the expected increase in global SNR exceeds 3-6 dB after switching to another mode. If the expected gain is lower than this threshold, it indicates that the two modes are not significantly different in the current environment, and maintaining the current mode while adjusting the transmission frequency and receiving gain is a better choice. After triggering the mode switch evaluation, the state decision unit will perform a process of calculating the expected global signal-to-noise ratio (SNR) for switching to another observation mode through digital twin simulation; in order to determine whether the expected SNR requirement can be met after switching to another mode; specifically including the following steps: The state decision unit retrieves geological feature data of the work area stored in the historical database, including resistivity distribution model of the target area, stratigraphic structure information, and geological interpretation results obtained from previous explorations; at the same time, it retrieves the forward modeling model corresponding to the current observation method from the theoretical model library. Based on the currently acquired measured data, the state decision unit rapidly updates the geological model to form a real-time geological model that reflects the current underground conditions. The model includes both historical geological features and the measured data obtained in this exploration, and has high accuracy. The state decision unit inputs the updated real-time geological model into the digital twin simulation engine to simulate the electromagnetic field response when switching to another observation mode; specifically, if the current mode is well-to-surface, it simulates the surface transmit-downhole receive response when switching to well-to-surface mode; if the current mode is well-to-surface, it simulates the downhole transmit-to-surface receive response when switching to well-to-surface mode. The simulation engine calculates the expected global signal-to-noise ratio after switching to another mode based on the simulated response data and the current real-time monitored environmental noise level. The calculation process also uses a weighted average fusion algorithm, but the input data is the theoretical response value generated by the simulation. The calculated expected global signal-to-noise ratio is output to the state decision unit for subsequent expected gain calculation; After obtaining the expected global signal-to-noise ratio (SNR), the state decision unit calculates the expected gain, which is the difference between the expected global SNR and the current global SNR; the specific calculation process is as follows: ;in, The expected global signal-to-noise ratio after switching to another observation mode, calculated through digital twin simulation. This represents the actual global signal-to-noise ratio under the current observation mode; the calculated value is... That is, the expected gain; The state decision unit will calculate the expected gain. With preset gain threshold Comparison: If This indicates that switching to another mode can meet the expected signal-to-noise ratio requirement. The state decision unit generates a mode switching instruction and switches the task state from executing to pending switching. If the expected signal-to-noise ratio requirement cannot be met after switching to another mode, or the improvement is limited and the switching conditions are not met, the state decision unit maintains the current mode and broadcasts parameter adjustment instructions to each terminal in the distributed acquisition module to guide each terminal to adjust the transmission frequency and receiving gain to adapt to the current interference environment. The parameter adjustment instructions include adjusting the transmitter's operating frequency to avoid strong interference frequency bands, adjusting the receiver's gain coefficient to optimize the signal's dynamic range, and adjusting the filter's cutoff frequency to better suppress out-of-band noise. After receiving the instructions, each terminal automatically executes the corresponding parameter adjustments by its local controller, thereby maximizing the data quality in the current mode without switching observation modes. The central control module, as the core hub of the system, realizes standardized parsing and instruction generation of exploration tasks through the task parsing unit, realizes real-time fusion of signal-to-noise ratio of multiple terminals and global quality assessment through the data fusion unit, and realizes state machine maintenance and intelligent switching decision of observation tasks through the state decision unit. The three work together to form a complete control closed loop from task issuance to quality monitoring.

[0022] Furthermore, the distributed acquisition module includes a ground receiving array and a string of downhole probes; The ground receiving array consists of multiple ground receiving terminals. Each ground receiving terminal is connected to the central control module via an industrial Ethernet and has a built-in local controller, GNSS timing module, high-precision ADC converter and FPGA edge computing unit, which are used to collect ground electric field and magnetic field response data in real time and calculate the local signal-to-noise ratio. The system includes a built-in local controller, GNSS timing module, high-precision ADC converter, and FPGA edge computing unit, used to acquire ground electric and magnetic field response data in real time and calculate the local signal-to-noise ratio. The specific process includes: After the ground receiving terminal is powered on, the local controller first initializes each functional module, including configuring the parameters of the GNSS timing module, setting the sampling rate and range of the high-precision ADC converter, and loading the algorithm program of the FPGA edge computing unit; the GNSS timing module receives GPS satellite signals to obtain high-precision time information in real time and generates a second pulse signal for synchronous acquisition timing; the local controller calibrates the system clock based on this time information to ensure that all ground receiving terminals are synchronized with the central control module. During the data acquisition phase, the high-precision ADC converter continuously samples the electric field signal connected to the electrode and the magnetic field signal connected to the magnetic probe at a preset sampling rate, converting the analog signal into a digital signal. The FPGA edge computing unit reads the digital signal data stream output by the ADC converter in real time, performs digital filtering on the data to remove power frequency interference and out-of-band noise. Subsequently, the FPGA divides the filtered data into segments according to fixed time windows, performs a fast Fourier transform on the data segments within each time window, and converts the time domain signal into a frequency domain signal. During the signal-to-noise ratio (SNR) calculation stage, the FPGA edge computing unit extracts signal energy and noise energy from the spectrum according to preset signal and noise frequency bands. Specifically, the signal frequency band is set according to the transmission frequency of the current observation mode, and the noise frequency band is selected from non-signal frequency bands near the signal frequency band. The formula for calculating the local SNR is: ;in, The average energy within the signal frequency band. The calculated local signal-to-noise ratio value, along with the corresponding timestamp, is encapsulated into a standard data packet by the local controller and periodically reported to the data fusion unit of the central control module via industrial Ethernet. The downhole probe string consists of multiple downhole receiving terminals connected in series. Each downhole receiving terminal is connected to the central control module via a power line carrier bus and has a built-in local controller, high-precision temperature-compensated crystal oscillator, and signal conditioning circuit. It is used to collect downhole electric and magnetic field response data in real time and calculate the local signal-to-noise ratio.

[0023] The system includes a built-in local controller, a high-precision temperature-compensated crystal oscillator, and signal conditioning circuitry, used for real-time acquisition of downhole electric and magnetic field response data and calculation of the local signal-to-noise ratio; the process specifically includes: Before being lowered into the drilling well, the downhole receiving terminal is initialized and configured, and then lowered to the predetermined depth via an armored cable. Since satellite signals cannot be received in the downhole environment, the terminal uses a high-precision temperature-compensated crystal oscillator as the local clock source. The crystal oscillator has extremely low temperature drift characteristics and can maintain high frequency stability in the downhole temperature variation environment. The signal conditioning circuit first amplifies and anti-aliasing filters the weak signals sensed by the electrodes and magnetic probe. The preamplifier adopts a low-noise design, and its gain can be adjusted according to preset parameters to adapt to signal strength changes at different depths. The anti-aliasing filter adopts a high-order low-pass filter, and the cutoff frequency is automatically set according to the sampling rate to prevent high-frequency noise from aliasing into the signal band. The conditioned analog signal is sent to the high-precision ADC built into the local controller for analog-to-digital conversion; the local controller uses a timer based on a temperature-compensated crystal oscillator to trigger ADC sampling to ensure the accuracy of the sampling interval; the sampled data is first digitally filtered to remove residual noise; then, the same algorithm as the ground receiving terminal is used to segment the data, perform Fourier transform and calculate the signal-to-noise ratio. The local signal-to-noise ratio data calculated by the downhole receiving terminal is modulated via the power line carrier bus and transmitted to the central control module through the core of the armored cable. The power line carrier communication technology uses the existing power supply cable as the transmission medium and employs frequency division multiplexing technology to modulate the digital signal onto a high-frequency carrier, which is then superimposed on the DC power supply signal for transmission. The carrier frequency range is 50kHz-500kHz. Through the coupling circuit, bidirectional transmission of power supply and signal is achieved, realizing bidirectional data communication between the downhole terminal and the ground control center without the need to lay additional dedicated signal lines. The preset parameter table for the target mode is a configuration database stored in the central control module and the local controllers of each terminal. It is used to define the working parameters of each terminal under different observation modes. The parameter table records the terminal configuration information corresponding to each observation mode in a structured form, including parameters such as sampling rate, gain coefficient, filtering frequency, transmission frequency, and acquisition duration. The parameter table is established based on theoretical analysis and engineering experience, and is pre-optimized for different exploration targets, different geological conditions, and different interference environments. During system operation, the central control module can dynamically update the parameter table content according to task requirements and distribute it to each terminal for synchronization through the communication network. The process of loading the corresponding sampling rate, gain coefficient, and filter frequency according to the preset parameter table of the target mode specifically includes: When the local controller receives a mode switching command from the central control module, it first parses the target mode identifier contained in the command. Then, it queries the configuration items corresponding to the mode from the preset parameter table stored locally, including the sampling rate value, gain coefficient, and filter frequency. According to the queried parameter values, the local controller reconfigures the sampling clock divider of the ADC converter, adjusts the gain level of the preamplifier, and updates the coefficients of the digital filter. After the configuration is completed, the local controller executes a self-test program to verify whether the parameters of each module have been correctly loaded. If an abnormal parameter configuration is detected, it reports an error status to the central control module and requests a resend of the command. The process of re-establishing clock synchronization with the central control module specifically includes: After receiving the mode switching command, the ground receiving terminal resynchronizes with the GNSS satellite signal, obtains the latest UTC time, and calibrates the local system clock. At the same time, it exchanges time information with the central control module through industrial Ethernet and uses the network time protocol for fine-tuning to ensure that the clock deviation with the central control module is within microseconds. Since the downhole receiving terminal cannot receive satellite signals, it adopts a synchronization mechanism based on power line carrier bus: the central control module periodically broadcasts a high-precision synchronization pulse signal through the power line carrier bus, which is generated based on the GNSS timing of the central control module; the downhole receiving terminal captures the synchronization pulse through the bus interface and uses a local temperature-compensated crystal oscillator to count the synchronization pulse interval, calculate the clock deviation with the central control module, and then adjust the count value of the local timer to achieve clock synchronization with the central control module; after synchronization is completed, the downhole receiving terminal reports the ready status to the central control module to confirm that clock synchronization has been established; The automatic execution process is completed within a preset short time after receiving the mode switching command. The preset short time refers to the upper limit of the time window set to ensure the continuity and comparability of the collected data. The setting of the time window takes into account factors such as the physical implementation speed of the switching operation, the time consumption of parameter loading, and the accuracy requirements of clock synchronization. It is usually set to 500 milliseconds to 1 second. Within this time window, the terminal needs to complete a series of operations such as parameter saving, new parameter loading, clock synchronization, and status reporting to ensure that the data collected in the new mode and the data before the switch are seamlessly connected on the timeline, avoiding data interruption or time misalignment caused by the switching process, and ensuring that subsequent data processing and inversion interpretation can be based on a continuous and aligned dataset. The distributed acquisition module, as the sensing end of the system, achieves multi-dimensional acquisition of electric and magnetic field response data through the three-dimensional deployment of ground receiving arrays and downhole probe strings. The local controller and signal-to-noise ratio calculation unit built into each terminal enable data quality assessment to be shifted from centralized processing to the edge, significantly improving the system response speed. Power line carrier bus technology realizes integrated transmission of power supply and communication, simplifying the complexity of downhole deployment.

[0024] Furthermore, the mode switching module includes a high-pressure switching matrix unit, a switching drive unit, and a ground-based transmitting electrode and a downhole transmitting electrode; The high-voltage switching matrix unit consists of multiple vacuum high-voltage relays, used to selectively connect the output terminal of the high-power transmitter to the ground transmitting electrode and the downhole transmitting electrode; The process of selectively connecting the output of the high-power transmitter to the surface transmitting electrode and the downhole transmitting electrode specifically includes: The high-voltage switching matrix unit employs an N×M relay array structure, where the input is connected to the positive and negative output terminals of the high-power transmitter, and the output is connected to the power supply lines of the surface transmitting electrode and the downhole transmitting electrode, respectively; each relay is independently controlled by a switching drive unit, forming different conduction paths by controlling the relay's energizing and de-energizing states; when the system operates in well mode, the switching drive unit sends an energizing command to the relay connected to the surface transmitting electrode, while keeping the relay connected to the downhole transmitting electrode in the de-energized state, thereby enabling the high-power transmitter to energize and de-energize. The output current of the transmitter flows underground through the ground transmitting electrode. When the system operates in well-to-ground mode, the switching drive unit sends an activation command to the relay connected to the underground transmitting electrode, while simultaneously disconnecting the line of the ground transmitting electrode, allowing the transmitting current to be delivered to the underground transmitting electrode via the armored cable. To ensure safe isolation under high-voltage conditions, the high-voltage switching matrix unit uses vacuum high-voltage relays, with contacts completely sealed in a vacuum environment. These relays have strong arc-extinguishing capabilities, high withstand voltage ratings, and stable contact resistance. The relay contact gap is designed to be ≥3mm, capable of withstanding high-voltage surges of several kilovolts. Simultaneously, physical isolation baffles are installed between the relays to prevent short-circuit faults caused by high-voltage breakdown or arcing. The switching drive unit is connected to the digital output terminal of the central control module. After receiving the mode switching command, it performs the following operations in sequence according to the preset timing logic: sending a power reduction command to the high-power transmitter, delaying and waiting for the current to cross zero, driving the high-voltage switching matrix to perform physical switching, and sending a power recovery command to the high-power transmitter. The preset timing logic refers to the pre-set operation sequence and time interval to ensure the safety and reliability of the switching process; the timing logic is stored in the firmware of the switching drive unit in the form of a state machine, and specifically includes the following steps: Power reduction phase: After receiving the mode switching command from the central control module, the switching drive unit immediately sends a power reduction command to the high-power transmitter via a dedicated control line, requiring the transmitter to reduce the output power to a safe threshold in the shortest possible time. Upon receiving the command, the transmitter quickly reduces the power by adjusting the inverter drive pulse width or reducing the DC bus voltage, and returns a power reduction confirmation signal to the switching drive unit after the power stabilizes. The purpose of this phase is to avoid high-current arcing caused by direct switching under load, thus protecting the relay contacts from damage. Zero-crossing detection and waiting phase: After receiving the power reduction confirmation signal, the switching drive unit starts the current zero-crossing detection circuit. The circuit monitors the waveform of the transmitter output current in real time through a high-precision current transformer, capturing the instantaneous zero point when the current transitions from the positive half-cycle to the negative half-cycle. When the current zero-crossing is detected, the switching drive unit starts a preset delay timer, which is usually set to 5-10 milliseconds to ensure that the current completely decays to zero. Switching at the zero-crossing point can minimize the generation of electric arcs and extend the service life of the relay. Matrix switching phase: After the delay ends, the switching drive unit sends relay drive signals to the high-voltage switching matrix unit according to the requirements of the target mode. Specifically, if the target mode is the well-ground mode, an activation pulse is sent to the relay connected to the surface transmitting electrode, and an disconnection pulse is sent to the relay connected to the downhole transmitting electrode. If the target mode is the well-to-ground mode, the opposite operation is performed. The drive signal is in the form of a high-voltage pulse to ensure reliable operation of the relay coil. The switching drive unit also monitors the feedback signals of each relay auxiliary contact to confirm whether the physical switching has been successfully completed. If an abnormality such as relay activation failure or contact sticking is detected, the switching process is immediately stopped, and a fault warning is reported to the central control module. Power recovery phase: After confirming that the high-voltage switching matrix has successfully switched to the target mode, the switching drive unit sends a power recovery command to the high-power transmitter via the control line, requesting the transmitter to gradually increase the output power to the target value; the transmitter slowly increases the power according to the preset soft-start curve to avoid impacting the switched circuit due to a sudden increase in power; after the power recovery is completed, the transmitter returns a power normal confirmation signal to the switching drive unit, and the switching drive unit then reports the switching completion status to the status decision unit of the central control module, and the entire switching process ends here; The switching drive unit also has a built-in status monitoring circuit that monitors the contact status of each relay in the switching matrix in real time and reports a fault warning to the central control module when an abnormality is detected. The status monitoring circuit determines the contact status by detecting the voltage drop across the main contacts of the relay. When the voltage drop exceeds 500mV, it is determined to be poor contact. At the same time, it verifies whether the main contacts are operating properly by detecting the on / off status of the auxiliary contacts. If the status of the auxiliary contacts does not match the expectation, it is determined to be contact adhesion or failure to engage. The status monitoring circuit determines whether the relay is working properly by detecting the voltage drop across the main contacts and the on / off status of the auxiliary contacts. When the relay is in the engaged state, the monitoring circuit detects the voltage drop across the main contacts. If the voltage drop exceeds a preset threshold, it is determined to be poor contact. When the relay is in the disengaged state, the monitoring circuit detects the on / off status of the auxiliary contacts. If the auxiliary contacts are abnormally closed, it is determined to be contact adhesion. The monitoring circuit also monitors the current waveform during the switching process in real time. If abnormalities such as zero-crossing detection failure or excessively long switching time occur, corresponding fault warning information is also generated. The ground transmitting electrodes are deployed on the ground surface to supply current to the underground in well mode. The ground transmitting electrodes are usually non-polarized electrodes or metal electrodes, which are deployed within the survey area at a certain electrode spacing. The electrodes have good contact with the ground to ensure that high-power current can be effectively injected into the underground. The deployment location, number and arrangement of the electrodes are determined according to the requirements of the exploration task, and are connected to the high-voltage switching matrix unit of the mode switching module through cables. The downhole transmitting electrode is installed on an armored cable and can be lowered into the well to supply current to the ground in well-to-surface mode. The downhole transmitting electrode is a ring-shaped metal electrode, fixed at a specific depth position on the armored cable. The electrode is connected to the surface mode switching module through a special wire inside the cable. During downhole operations, the lowering position of the electrode is determined according to the target depth. The electrode string is lowered to the predetermined depth by a wellhead winch. The electrode contacts the well wall or well fluid and directly injects the transmitting current into the deep target formation. The mode switching module, as the system's actuator, enables selective connection between the high-power transmitter and the ground or underground transmitting electrode through a high-voltage switching matrix unit. The switching drive unit controls power rise and fall and zero-crossing switching according to precise timing logic, ensuring the safety and continuity of the switching process. The built-in status monitoring circuit detects the contact status in real time, providing strong assurance for system reliability.

[0025] Example 2 Please see Figure 3 This embodiment provides a high-power well-to-ground integrated intelligent joint observation method, which is applied to the high-power well-to-ground integrated intelligent joint observation system as described in Embodiment 1. Through the collaborative work of the central control module, the distributed acquisition module and the mode switching module, intelligent quality control and adaptive mode switching of the entire exploration data acquisition process are realized.

[0026] The central control module connects to the external exploration task management system, parses the exploration task data stream, and generates observation mode execution instructions with unique identifiers. These instructions are associated with target geological body information, observation frequency band, transmission power, and planned execution time, thereby establishing a monitoring benchmark for subsequent quality control. Specifically, the task parsing unit of the central control module first establishes a communication connection with the external exploration task management system to monitor and acquire newly issued exploration task data streams in real time. For the received task data, the task parsing unit uses a rule-based information extraction algorithm to identify and extract key fields from the structured or semi-structured task description text: extracting target geological body information such as spatial location coordinates and depth range; extracting observation frequency band and transmission power parameters such as observation method type, working frequency range, and transmission current intensity; extracting planned execution time information such as task start time, end time, and acquisition duration at each measuring point. Subsequently, the task parsing unit assigns a globally unique task sequence number to the extracted information, assembles it into a structured initial observation mode execution instruction, and sends the instruction to the state decision unit for subsequent state management. After receiving the initial instruction, the state decision unit sets the initial state of the observation task to pending execution and stores the task information in the event log. The ground receiving terminal and the downhole receiving terminal in the distributed acquisition module acquire data according to the initial observation mode. Each terminal calculates the local signal-to-noise ratio in real time and periodically reports it to the central control module. The ground receiving array consists of multiple ground receiving terminals, each connected to the central control module via an industrial Ethernet. During the data acquisition phase, the high-precision ADC converter built into each ground receiving terminal continuously samples the electric field signal from the electrodes and the magnetic field signal from the magnetic probe at a preset sampling rate, converting the analog signal into a digital signal. The FPGA edge computing unit reads the digital signal data stream output by the ADC converter in real time, performs digital filtering to remove power frequency interference and out-of-band noise. Subsequently, the FPGA segments the filtered data into fixed time windows, performs a fast Fourier transform on the data segment within each time window, converting the time-domain signal into a frequency-domain signal. During the signal-to-noise ratio (SNR) calculation phase, the FPGA edge computing unit extracts signal energy and noise energy from the spectrum according to preset signal and noise frequency bands, and calculates the local SNR according to the method described in Example 1. The calculated local SNR value, along with the corresponding timestamp, is encapsulated into a standard data packet by the local controller and periodically reported to the data fusion unit of the central control module via the industrial Ethernet. The downhole probe string consists of multiple downhole receiving terminals connected in series. Each downhole receiving terminal is connected to the central control module via a power line carrier bus. The downhole receiving terminal completes initial configuration before being lowered into the drilling well and is then lowered to the predetermined depth via an armored cable. Since satellite signals cannot be received in the downhole environment, the terminal uses a high-precision temperature-compensated crystal oscillator as its local clock source. This crystal oscillator has extremely low temperature drift characteristics and can maintain high frequency stability under varying downhole temperature conditions. The signal conditioning circuit first amplifies and anti-aliasing filters the weak signals sensed by the electrodes and magnetic probe. The conditioned analog signal is then sent to the high-precision ADC built into the local controller for analog-to-digital conversion. The local controller uses a timer based on the temperature-compensated crystal oscillator to trigger ADC sampling, ensuring the accuracy of the sampling interval. The sampled data is first digitally filtered to remove residual noise. Subsequently, using the same algorithm as the ground receiving terminal, the data is segmented, Fourier transformed, and the signal-to-noise ratio (SNR) is calculated. The calculated local SNR data is modulated via the power line carrier bus and transmitted to the data fusion unit of the central control module via the core of the armored cable. The central control module performs multi-source data fusion on the local signal-to-noise ratios reported by all terminals and calculates the global signal-to-noise ratio under the current observation mode; The data fusion unit establishes communication links with all ground receiving terminals and downhole receiving terminals. Each terminal periodically reports its calculated local signal-to-noise ratio (SNR) value according to a preset frequency. After receiving these reported data, the data fusion unit first performs data cleaning to remove obviously abnormal values. Then, it uses the same weighted average fusion algorithm as in Example 1 to calculate the global SNR. The algorithm dynamically adjusts the weight coefficients by comprehensively considering factors such as the geographical location and depth of each terminal, so that the calculated global SNR can more accurately reflect the overall data quality under the current observation mode. The calculated global SNR, along with the corresponding timestamp, is sent to the status decision unit in real time as input data for subsequent decisions. The central control module compares the global signal-to-noise ratio with the expected signal-to-noise ratio requirement. When the global signal-to-noise ratio does not meet the expected signal-to-noise ratio requirement, it automatically decides whether to perform the observation mode switch based on the target geological body information and the switching effect evaluation of the geological characteristics of the work area. If the decision is made to perform the switch, a mode switching command is generated. The state decision unit receives the global signal-to-noise ratio calculated by the data fusion unit in real time and compares the global signal-to-noise ratio with the preset low threshold for global signal-to-noise ratio, while monitoring the duration of the value being below the threshold. The low threshold for global signal-to-noise ratio is set comprehensively based on historical data of the work area, environmental noise level, and the data quality requirements of the exploration target, and is usually set in the range of 10-30dB. The duration threshold is used to prevent misjudgment caused by instantaneous interference and is usually set to 3-5 consecutive sampling periods. When the global signal-to-noise ratio falls below the low threshold and the duration exceeds the set value, the mode switching evaluation process is triggered. The state decision unit retrieves the geological features and theoretical models of the work area from the historical database, updates the real-time geological model based on the currently collected measured data, and inputs the real-time geological model into the digital twin simulation engine for forward modeling to obtain the electromagnetic field response data when switching to another observation mode. Based on the response data and the current environmental noise level, the expected global signal-to-noise ratio is calculated. Specifically, the process includes the following sub-steps: The state decision unit retrieves geological feature data of the work area stored in the historical database, including resistivity distribution model of the target area, stratigraphic structure information, and geological interpretation results obtained from previous explorations; at the same time, it retrieves the forward modeling model corresponding to the current observation method from the theoretical model library. Based on the currently collected measured data, the state decision unit quickly updates the geological model to form a real-time geological model that can reflect the current underground conditions. The state decision unit inputs the updated real-time geological model into the digital twin simulation engine to simulate the electromagnetic field response when switching to another observation mode; specifically, if the current mode is well-to-surface, it simulates the surface transmit-downhole receive response when switching to well-to-surface mode; if the current mode is well-to-surface, it simulates the downhole transmit-to-surface receive response when switching to well-to-surface mode. Based on the simulated response data and the currently monitored ambient noise level, the simulation engine calculates the expected global signal-to-noise ratio after switching to another mode. The calculation process is the same as the global signal-to-noise ratio calculation method in step three; The calculated expected global signal-to-noise ratio Output to the state decision unit; After obtaining the expected global signal-to-noise ratio, the state decision unit calculates the expected gain. And compare the expected gain with the preset gain threshold. The comparison is performed; the preset gain threshold is usually set at 3-6dB, meaning that the switching is considered valuable only if the expected global signal-to-noise ratio improvement exceeds 3-6dB after switching to another mode.

[0027] like This indicates that switching to another mode can significantly improve data quality, meeting the mode switching conditions. The state decision unit generates a mode switching instruction and switches the observation task status from "executing" to "pending switching." This indicates that the improvement brought by switching to another mode is limited and the switching conditions are not met. The state decision unit maintains the current mode and broadcasts parameter adjustment instructions to each terminal in the distributed acquisition module to guide each terminal to adjust the transmission frequency and reception gain to adapt to the current interference environment. The parameter adjustment instructions include adjusting the operating frequency of the transmitter to avoid strong interference frequency bands, adjusting the gain coefficient of the receiving terminal to optimize the signal dynamic range, and adjusting the cutoff frequency of the filter to better suppress out-of-band noise. The central control module sends a mode switching command to the mode switching module, driving the mode switching module to perform a physical switch between well-to-ground mode and ground-to-well mode; After receiving the mode switching command from the central control module, the mode switching module's switching drive unit performs the following operations sequentially according to the preset timing logic: First, the switching drive unit sends a power reduction command to the high-power transmitter via a dedicated control line, requiring the transmitter to reduce the output power to a safe threshold in the shortest possible time. After receiving the command, the transmitter quickly reduces the power by adjusting the inverter drive pulse width or reducing the DC bus voltage, and returns a power reduction confirmation signal to the switching drive unit after the power stabilizes. The purpose of these steps is to avoid high-current arcing caused by direct switching under load, and to protect the relay contacts from damage.

[0028] Secondly, after receiving the power reduction confirmation signal, the switching drive unit activates the current zero-crossing detection circuit. This circuit monitors the waveform of the transmitter's output current in real time through a high-precision current transformer, capturing the instantaneous zero point when the current transitions from the positive half-cycle to the negative half-cycle. When the current zero-crossing is detected, the switching drive unit starts a preset delay timer, typically set to 5-10 milliseconds, to ensure that the current completely decays to zero. Switching at the zero-crossing point can minimize the generation of electric arcs and extend the service life of the relay. Next, after the delay ends, the switching drive unit sends relay drive signals to the high-voltage switching matrix unit according to the requirements of the target mode. Specifically, if the target mode is the well-ground mode, it sends an engaging pulse to the relay connected to the surface transmitting electrode and an disconnecting pulse to the relay connected to the downhole transmitting electrode. If the target mode is the well-to-surface mode, the reverse operation is performed. The drive signal is in the form of a high-voltage pulse to ensure reliable operation of the relay coil. The switching drive unit also monitors the feedback signals of each relay auxiliary contact to confirm whether the physical switching has been successfully completed. If any abnormality such as relay engagement failure or contact sticking is detected, the switching process is immediately stopped and a fault warning is reported to the central control module. Finally, after confirming that the high-voltage switching matrix has been successfully switched to the target mode, the switching drive unit sends a power recovery command to the high-power transmitter through the control line, requesting the transmitter to gradually increase the output power to the target value; the transmitter slowly increases the power according to the preset soft-start curve to avoid impacting the switched circuit due to a sudden increase in power; after the power recovery is completed, the transmitter returns a power normal confirmation signal to the switching drive unit, and the switching drive unit then reports the switching completion status to the status decision unit of the central control module; After the switch is completed, each terminal in the distributed acquisition module automatically loads the preset parameters of the new mode, continues data acquisition and repeats the above steps until the exploration task is completed. Upon receiving a mode switching command from the central control module, the local controller of each ground receiving terminal and downhole receiving terminal automatically performs the following operations: Save the current working parameters to the local cache so that they can be quickly restored or used for fault rollback when needed; Based on the preset parameter table of the target mode, the corresponding sampling rate, gain coefficient, and filter frequency are loaded. The preset parameter table is a configuration database stored in the central control module and local controllers of each terminal, recording the terminal configuration information corresponding to each observation mode in a structured form. The local controller first parses the target mode identifier contained in the instruction, queries the configuration item corresponding to the mode from the locally stored preset parameter table, and then reconfigures the sampling clock divider of the ADC converter, adjusts the gain level of the preamplifier, and updates the coefficients of the digital filter. The clock synchronization with the central control module is re-established; the ground receiving terminal re-synchronizes with the GNSS satellite signal, obtains the latest UTC time, and calibrates the local system clock; simultaneously, it exchanges time information with the central control module via industrial Ethernet, and uses network time protocol for fine-tuning to ensure that the clock deviation with the central control module is within microseconds; the downhole receiving terminal adopts a synchronization mechanism based on power line carrier bus: the central control module periodically broadcasts high-precision synchronization pulse signals through the power line carrier bus, the downhole receiving terminal captures the synchronization pulses through the bus interface, and uses a local temperature-compensated crystal oscillator to count the synchronization pulse intervals, calculates the clock deviation with the central control module, and then adjusts the count value of the local timer to achieve clock synchronization; Enter the data acquisition state in the new mode and report the ready status to the central control module. The ready status includes confirmation of successful parameter loading, clock synchronization deviation value and normal hardware self-test indicator, confirming that the terminal is ready and can start data acquisition in the new mode. The above-mentioned automatic execution process is completed within a preset short time after receiving the mode switching command. The preset short time is usually between 500 milliseconds and 1 second. Within this time window, the terminal needs to complete a series of operations such as parameter saving, new parameter loading, clock synchronization, and status reporting to ensure that the data acquisition in the new mode and the data before the switch are seamlessly connected on the time axis, avoid data interruption or time misalignment caused by the switching process, and ensure that subsequent data processing and inversion interpretation can be based on a continuous and aligned dataset. Throughout the entire process of method execution, the central control module also performs full-process traceability management steps to provide data support for post-analysis, quality assessment and system optimization; The central control module's status decision unit records the local signal-to-noise ratio (SNR) data reported by all ground and downhole receiving terminals in real time, forming a data quality time series for each terminal; it records the global SNR time series calculated by the data fusion unit, reflecting the overall data quality trend; it records the generation time, triggering reason, and expected gain value of each mode switching command, completely preserving the basis for the switching decision; it records the start and end times, switching results, and status monitoring data of the mode switching module, providing a basis for reliability analysis of the switching process; and it records the parameter loading status and ready time of each terminal in the distributed acquisition module after mode switching, confirming whether the terminal has successfully entered the new mode. The state decision unit associates and stores all recorded data with the unique identifier of the execution instruction in the observation mode, forming a full-process traceable management log containing all recorded data. The log is stored in a structured form in the local database of the central control module, and supports querying and exporting in multiple ways such as by task, by time, and by terminal. It can be used for data quality assessment, system performance analysis, fault diagnosis, and subsequent task parameter optimization after the exploration is completed. Through the coordinated execution of the above steps, this method achieves closed-loop intelligent control of the entire process from exploration task analysis, data acquisition, quality assessment, mode switching decision-making, physical switching execution to terminal parameter adjustment. It effectively solves the technical problems of fixed observation modes, delayed manual switching, and inability to assess data quality in real time in existing technologies, and realizes a technical leap from blind post-collection processing to in-process quality interception.

[0029] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A high-power well-to-surface integrated intelligent joint observation system, characterized in that: It includes a central control module, a distributed acquisition module, and a mode switching module; The central control module is used to interface with the external exploration task management system, receive and parse the exploration task data stream, and generate observation mode execution instructions with unique identifiers. The instructions include target geological body information and corresponding expected signal-to-noise ratio requirements. The system receives the local signal-to-noise ratios (SNRs) reported in real time by surface and downhole receiving terminals in the distributed acquisition module. It performs multi-source data fusion on the local SNRs reported by each terminal and calculates the global SNR under the current observation mode. When the global SNR does not meet the expected SNR requirement, it automatically decides whether to switch the observation mode based on the target geological body information and the evaluation of the switching effect of the geological characteristics of the work area. The distributed acquisition module is communicatively connected to the central control module and includes a ground receiving terminal and an underground receiving terminal. Both the ground receiving terminal and the underground receiving terminal have built-in local controllers and signal-to-noise ratio calculation units, which are used to synchronously acquire electric field and magnetic field response data when the high-power transmitter supplies current to the ground, and calculate the local signal-to-noise ratio based on the response data and report it to the central control module. The mode switching module is connected to the central control module and the high-power transmitter, and is controlled by the central control module. It is used to perform physical switching between well-to-ground mode and well-to-ground mode when it receives a mode switching command issued by the central control module. Well-to-ground mode is an observation mode of downhole transmission and ground reception, and well-to-ground mode is an observation mode of ground transmission and downhole reception. The central control module is also used to control the mode switching module to perform the switching after generating the mode switching instruction, and to notify each terminal in the distributed acquisition module to automatically load the preset working parameters of the new mode after the switching and continue data acquisition.

2. The intelligent joint observation system according to claim 1, characterized in that, The central control module includes a task parsing unit, a data fusion unit, and a status decision unit. The task parsing unit is configured to receive exploration task data streams from the exploration task management system, parse and extract key fields such as target geological body information, observation frequency band, transmission power, planned execution time and corresponding expected signal-to-noise ratio requirements from the exploration task data streams, and generate initial observation mode execution instructions. The data fusion unit is configured to receive local signal-to-noise ratio data reported in real time by all ground receiving terminals and downhole receiving terminals, and calculate the global signal-to-noise ratio under the current observation mode through a multi-source data fusion algorithm. The state decision unit is configured to maintain the state machine of the observation task; the state machine includes the states of task creation, pending execution, execution, pending switching, and completed; the unit is further configured to: listen to the local signal-to-noise ratio (SNR) reported data from the distributed acquisition module and the global SNR calculation result from the data fusion unit, compare the global SNR with the expected SNR requirement in the instruction, trigger a mode switching evaluation when the global SNR does not meet the expected SNR requirement, and drive the state switching according to a predefined state-event mapping rule, the state-event mapping rule defines the next state to switch to and the action to be performed when a specific event occurs in the current state, the specific event includes one of the following: the planned execution time arrives, the switching completion is confirmed, or all preset acquisition quantities are completed, and store the event log for each state switching, the event log includes the state identifier before and after the state switching, the triggering event, and the timestamp; The state decision unit is also used to receive fault warnings reported by the mode switching module. The fault warnings include relay contact failure warnings, current zero-crossing detection failure warnings, and power recovery abnormality warnings. The unit then performs corresponding processing according to the predefined mapping relationship between fault types and processing measures. The processing measures include recording fault information, pausing the switching operation, automatically retrying the switching, and triggering an emergency shutdown.

3. The intelligent joint observation system according to claim 2, characterized in that, The process of maintaining the state machine for the observation task specifically includes: When the task parsing unit generates a complete initial observation mode execution instruction, the initial state of the observation task is set to pending execution. When the planned execution time of the observation task reaches the predefined execution window, the task status is switched from pending execution to execution, and the distributed acquisition module is notified to start data acquisition. When the mode switching conditions determined by the preset decision logic are met, the task status is switched from executing to pending switching. If a switch occurs, after receiving a switch completion confirmation signal from the switch drive unit of the mode switch module, and after the central control module verifies the switch success based on the status monitoring data carried in the signal, the task status is switched from pending switch back to execution, and data acquisition continues. When all the preset data collection for the observation task is completed, the task status will be switched to "completed".

4. The intelligent joint observation system according to claim 2, characterized in that, The process of comparing the global signal-to-noise ratio (SNR) with the expected SNR requirement in the instruction, and triggering a mode switching evaluation when the global SNR does not meet the expected SNR requirement, specifically includes: Preset global signal-to-noise ratio low threshold, duration threshold, and expected gain threshold; When the global signal-to-noise ratio is lower than the low threshold and the duration exceeds the duration threshold, it is confirmed that the expected signal-to-noise ratio requirement has not been met, and a mode switching evaluation is triggered. The geological features and theoretical models of the work area are retrieved from the historical database. A real-time geological model is updated based on the currently collected measured data. The real-time geological model is then input into a digital twin simulation engine for forward modeling to obtain electromagnetic field response data when switching to another observation mode. The expected global signal-to-noise ratio is then calculated based on the response data and the current environmental noise level. Calculate the expected gain, which is the difference between the expected global signal-to-noise ratio and the global signal-to-noise ratio under the current observation mode; If the expected gain exceeds the expected gain threshold, a mode switching instruction is generated to switch the task status from executing to pending switching. If the expected gain does not exceed the expected gain threshold, the current mode is maintained, but parameter adjustment instructions are broadcast to each terminal in the distributed acquisition module to adjust the transmission frequency and reception gain to adapt to the current interference environment.

5. The intelligent joint observation system according to claim 1, characterized in that, The distributed acquisition module includes a ground receiving array and a string of downhole probes; The ground receiving array consists of multiple ground receiving terminals. Each ground receiving terminal is connected to the central control module via an industrial Ethernet and has a built-in local controller, GNSS timing module, high-precision ADC converter, and FPGA edge computing unit. The GNSS timing module is used to provide a unified time reference for data acquisition. The high-precision ADC converter is used to convert analog electric and magnetic field signals into digital signals. The FPGA edge computing unit is used to perform filtering, Fourier transform, and local signal-to-noise ratio calculation on the digital signals. The local controller is used to coordinate the work of each module and report the calculation results. The downhole probe string consists of multiple downhole receiving terminals connected in series. Each downhole receiving terminal is connected to the central control module via a power line carrier bus and has a built-in local controller, high-precision temperature-compensated crystal oscillator and signal conditioning circuit, which is used to collect downhole electric and magnetic field response data in real time and calculate the local signal-to-noise ratio. The power line carrier bus utilizes the core of the armored cable as the transmission medium, simultaneously supplying power to the downhole receiving terminal and transmitting data.

6. The intelligent joint observation system according to claim 5, characterized in that, Upon receiving a mode switching command from the central control module, the local controller of each of the aforementioned ground receiving terminals and downhole receiving terminals automatically performs the following operations: Save the current working parameters to the local cache; Based on the preset parameter table of the target mode, load the corresponding sampling rate, gain coefficient and filtering frequency; Re-establish clock synchronization with the central control module; Enter the data acquisition state in the new mode and report the ready status to the central control module. The ready status includes confirmation of successful parameter loading, clock synchronization deviation value and hardware self-test normal indicator. The automatic execution process is completed within a preset time after receiving the mode switching command, ensuring the continuity and comparability of the collected data.

7. The intelligent joint observation system according to claim 1, characterized in that, The mode switching module includes a high-pressure switching matrix unit, a switching drive unit, and a ground-based transmitting electrode and a downhole transmitting electrode; The high-voltage switching matrix unit consists of multiple vacuum high-voltage relays, used to selectively connect the output terminal of the high-power transmitter to the ground transmitting electrode and the downhole transmitting electrode; The switching drive unit is connected to the digital output terminal of the central control module. After receiving the mode switching command, it performs the following operations in sequence according to the preset timing logic: sending a power reduction command to the high-power transmitter, delaying and waiting for the current to cross zero, driving the high-voltage switching matrix to perform physical switching, and sending a power recovery command to the high-power transmitter. The switching drive unit also has a built-in status monitoring circuit to detect the contact status of each relay in the switching matrix in real time, and to report a fault warning to the central control module when an abnormality is detected. The ground-based transmitting electrodes are deployed on the ground surface and are used to supply current underground in well mode; The downhole transmitting electrode is mounted on an armored cable and can be lowered into the well to supply current to the underground in well-to-surface mode.

8. A high-power well-to-surface integrated intelligent joint observation method based on the system described in any one of claims 1 to 7, characterized in that, Includes the following steps: The central control module connects to the exploration task management system, parses the exploration task data stream, and generates observation mode execution instructions with unique identifiers. The instructions include target geological body information, observation frequency band, transmission power, planned execution time, and corresponding expected signal-to-noise ratio requirements. The ground receiving terminal and the downhole receiving terminal in the distributed acquisition module acquire data according to the initial observation mode. Each terminal calculates the local signal-to-noise ratio in real time and periodically reports it to the central control module. The central control module performs multi-source data fusion on the local signal-to-noise ratios reported by all terminals and calculates the global signal-to-noise ratio under the current observation mode; The central control module compares the global signal-to-noise ratio with the expected signal-to-noise ratio requirement. When the global signal-to-noise ratio does not meet the expected signal-to-noise ratio requirement, it automatically decides whether to perform the observation mode switch based on the target geological body information and the switching effect evaluation of the geological characteristics of the work area. If the decision is made to perform the switch, a mode switching command is generated. The central control module sends a mode switching command to the mode switching module, driving the mode switching module to perform a physical switch between well-to-ground mode and ground-to-well mode; After the switch is completed, each terminal in the distributed acquisition module automatically loads the preset parameters of the new mode, continues data acquisition, and repeats the above steps until the exploration task is completed.

9. The intelligent joint observation method according to claim 8, characterized in that, The central control module compares the global signal-to-noise ratio (SNR) with the expected SNR requirement. When the global SNR does not meet the expected SNR requirement, it automatically decides whether to switch the observation mode based on the target geological body information and the switching effect evaluation of the geological characteristics of the work area. Specifically, this includes: The central control module's state decision unit receives the global signal-to-noise ratio calculated by the data fusion unit in real time; compares the global signal-to-noise ratio with a preset low threshold for global signal-to-noise ratio, and monitors the duration of the value being below the threshold. When the global signal-to-noise ratio is lower than the low threshold and the duration exceeds the set value, it is confirmed that the expected signal-to-noise ratio requirement is not met, and the mode switching evaluation process is triggered. The state decision unit retrieves the geological features and theoretical models of the work area from the historical database, updates the real-time geological model based on the currently collected measured data, inputs the real-time geological model into the digital twin simulation engine for forward modeling, obtains the electromagnetic field response data when switching to another observation mode, and calculates the expected global signal-to-noise ratio based on the response data and the current environmental noise level. Obtain the current global signal-to-noise ratio calculated by the data fusion unit, calculate the expected gain, which is the difference between the expected global signal-to-noise ratio and the current global signal-to-noise ratio, and compare the expected gain with a preset gain threshold. If the expected gain exceeds the preset gain threshold, a mode switching instruction is generated, and the observation task status is switched from executing to pending switching. If the expected gain does not exceed the preset gain threshold, the current mode is maintained, but a parameter adjustment instruction is broadcast to each terminal in the distributed acquisition module to adjust the transmission frequency and the receiving gain.

10. The intelligent joint observation method according to claim 8, characterized in that, It also includes full-process traceability management steps: The status decision unit of the central control module records the local signal-to-noise ratio data reported by all ground receiving terminals and downhole receiving terminals in real time; Record the global signal-to-noise ratio time series calculated by the data fusion unit; Record the generation time, triggering reason, and expected gain value of each mode switching command; Record the start and end times, switching results, and status monitoring data of the mode switching module. Record the parameter loading status and ready time of each terminal in the distributed acquisition module after mode switching; All recorded data are associated and stored according to a unique identifier to form a full-process traceable management log containing all recorded data, which is used for post-event analysis, quality assessment and system optimization.

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