TRT soft start and hard manual intervention combined emergency intervention of direct current accident oil pump control system

Abstract

The application discloses a TRT soft start and hard manual operation emergency intervention integrated direct current accident oil pump control system and relates to the technical field of oil pump control, which comprises a baseline pressure calculation module, a negative body identification module and a continuous control module.The baseline pressure calculation module is used for calculating the baseline pressure value of pressure oil in a lubricating system in a vertical shaft riser.The negative body identification module is used for judging whether to generate the negative body area quantity at the current time based on the pump outlet pressure at the outlet of an accident oil pump and the instantaneous volume flow of the vertical shaft riser.The continuous control module is used for continuously controlling the operating state of the accident oil pump based on the negative body area quantity at the current time.The application realizes smooth starting and rapid pressure building.

Description

Technical Field

[0001] This invention relates to the field of oil pump control technology, and in particular to a DC emergency oil pump control system that integrates TRT soft start and hard manual emergency intervention. Background Technology

[0002] In complex energy equipment systems such as large hydropower stations, underground powerhouses, and pumped storage power stations, the DC emergency oil pump is a core device for maintaining the pressure of the lubrication and speed regulation systems during power outages, shutdowns, or accidents. This system typically consists of a vertical shaft riser, oil storage tank, emergency oil pump, pipeline valve assembly, and industrial control software. In the event of power failure, it uses DC power to drive the oil pump, and the coordination logic of the control software maintains the continuity of the oil column in the vertical shaft riser, establishing a stable oil column for the elevation difference oil circuit, thereby preventing dry friction or pressure loss damage to critical components of the unit. Due to the significant geometric height difference of the vertical shaft riser and the inertial effect of the oil column, the oil often experiences alternating changes in liquid plugs, cavitation cavitation zones, and other phenomena during start-up and shutdown, leading to pressure reduction along the flow path and severe local pressure fluctuations. To address this issue, the industrial control software, combined with a TRT soft starter based on Insulated Gate Bipolar Transistor (IGBT) voltage regulation technology, smoothly controls the starting current and mechanical shock, enabling the emergency oil pump to achieve flexible start-up and shutdown under low-voltage power, avoiding oil column breakage. Meanwhile, the industrial control software can receive signal input from the manual intervention circuit in the event of a sudden pressure failure or system blockage, and automatically generate start-stop commands to achieve seamless manual switching of the pump unit. By combining the TRT soft-start control with the automated monitoring, logic judgment, and emergency intervention functions of the industrial control software, the system can not only quickly restore the continuity and pressure balance of the oil column in the vertical shaft riser under power failure, but also achieve a smooth transition of the oil circuit status when the equipment restarts, thus improving the stability and reliability of the emergency oil supply system.

[0003] In existing technologies, TRT soft start and hard manual emergency intervention have not yet been organically integrated. Their control logics are independent and lack coordinated judgment based on the fluid state of the riser. When the hydraulic plug breaks or a negative segment forms in the riser oil column during the initial start-up phase, the oil pump outlet pressure signal is prone to momentary reversal, causing the soft start module to misjudge the start-up completion or result in output limiting. Manual intervention, lacking real-time fluid state feedback, is delayed, leading to conflict and mutual cancellation between the soft and hard control methods. Existing systems mostly rely on empirical threshold settings or fixed injection volume adjustments, failing to adaptively adjust the control logic according to the oil column head recovery process, resulting in unstable pressure recovery, oil supply fluctuations, and oil column re-collapse. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies that cannot adaptively adjust the control logic according to the oil column head recovery process, resulting in unstable pressure recovery, oil supply fluctuations, and oil column collapse. The invention proposes a DC emergency oil pump control system that integrates TRT soft start and hard manual emergency intervention.

[0005] To address the problems existing in the prior art, the present invention adopts the following technical solution: The DC emergency oil pump control system, which integrates TRT soft start and hard manual emergency intervention, includes: The baseline pressure calculation module is used to calculate the baseline pressure value of the pressure oil in the vertical shaft riser of the lubrication system; The negative body identification module is used to determine whether to generate the negative body area at the current moment based on the pump outlet pressure at the outlet of the emergency oil pump and the instantaneous volumetric flow rate of the vertical shaft riser. The continuous control module is used to continuously control the operating status of the emergency oil pump based on the current negative volume area. The gate signal setting module is used to set the logic gate signal between the emergency oil pump and the vertical shaft riser based on the current negative body area and the pump outlet pressure at the emergency oil pump outlet after the continuous control ends. The injection volume update module is used to calculate and update the single injection volume after the signal setting is completed; The next injection initialization module is used to inject the next volume package into the emergency oil pump based on the updated single injection volume.

[0006] Preferably, calculating the baseline pressure value of the pressure oil in the lubrication system within the vertical shaft riser includes: To obtain the density of the pressurized oil in the lubrication system; Obtain the vertical height difference of the shaft riser; The hydrostatic pressure generated inside the vertical shaft riser due to the geometric height difference is obtained by multiplying the density of the pressurized oil, the vertical height difference of the riser, and the gravitational acceleration. Obtain the instantaneous volumetric flow rate through the vertical shaft riser; Multiply the preset friction coefficient by the square of the instantaneous volumetric flow rate to obtain the friction pressure drop of the pressurized oil. The baseline pressure value of the pressurized oil in the vertical shaft riser is obtained by adding the hydrostatic pressure and the pressure drop due to friction along the shaft.

[0007] Preferably, determining whether to generate a negative volumetric area at the current moment based on the pump outlet pressure at the accident oil pump outlet and the instantaneous volumetric flow rate of the vertical shaft riser includes: Obtain the pump outlet pressure at the outlet of the emergency oil pump; Differential processing is performed on the two pump outlet pressures at adjacent sampling times to obtain the pressure increment of adjacent volume micro-segments; The instantaneous volumetric flow rate of the vertical shaft riser is integrated over time to obtain the cumulative discharge rate; The cumulative displacement at two adjacent sampling times is differentially processed to obtain the displacement increment of adjacent volume micro-segments; The ratio of the pressure increment to the displacement increment of adjacent volume micro-segments is calculated to obtain discrete ratios; Obtain the negative volume area of ​​the vertical shaft oil column in the vertical shaft riser at the previous moment; If all discrete ratios are greater than 0, the negative volume area of ​​the previous time step remains unchanged; otherwise, the negative volume area of ​​the previous time step is updated to obtain the negative volume area of ​​the current time step.

[0008] Preferably, updating the negative volume area at the previous time step to obtain the negative volume area at the current time step includes: The minimum value of the discrete ratio is compared with 0 to obtain the negative slope ratio. The area of ​​the negative slope volume segment is obtained by multiplying the negative slope ratio and the displacement increment of the adjacent volume micro-segment. The area of ​​all negative slope volume segments is summed to obtain the summation result; The difference between the negative volume area at the previous moment and the accumulated result is calculated to obtain the negative volume area at the current moment.

[0009] Preferably, the operating status of the emergency oil pump is continuously controlled based on the current negative volume area, including: The volume of a single injection is calculated by multiplying the inner diameter cross-sectional area of ​​the shaft riser and the lifting height of the shaft riser. The correction term is calculated based on the negative volume area at the current moment; The cumulative discharge volume, single injection volume, and correction items of the vertical shaft riser at the current moment are added together to obtain the target volume value; The operating status of the emergency oil pump is continuously controlled based on the target volume value.

[0010] Preferably, the logic gate signal between the emergency oil pump and the vertical shaft riser is set based on the current negative volume area and the pump outlet pressure at the emergency oil pump outlet, including: If the negative volume area is 0 at the current moment and the pump outlet pressure at the emergency pump outlet is greater than or equal to the baseline pressure value, then the logic gate signal between the emergency pump and the vertical shaft riser is set to 1; otherwise, the logic gate signal is set to 0.

[0011] Preferably, calculating the updated single injection volume includes: The instantaneous volumetric flow rate at two adjacent sampling times is differentially processed to obtain the instantaneous flow rate change; Calculate the pressure difference before the valve of the pre-regulating valve in the vertical shaft riser; The current response ratio is obtained by calculating the ratio of the instantaneous flow rate change to the pressure difference before the valve. Divide the baseline response ratio of the vertical shaft riser by the current response ratio to obtain the volume correction ratio. The volume of a single injection is updated based on the volume correction ratio to obtain the updated volume of a single injection.

[0012] Preferably, the next round of volumetric injection into the emergency oil pump is performed based on the updated single injection volume, including: The target volume value is updated based on the updated single injection volume to obtain the updated target volume value. The next round of volumetric injection is performed on the emergency oil pump based on the updated target volume value.

[0013] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention calculates the baseline pressure value in the vertical shaft riser, identifies the negative volume area of ​​the oil column, and updates the target volume value in real time. This ensures that the output current and acceleration process during the TRT soft start phase are consistent with the actual pressure state of the oil column. This avoids the misjudgment problem caused by the traditional soft start control ignoring the discontinuity of the oil column. It effectively prevents oil column collapse and fluid oscillation in the early stage of oil pump startup, achieving smooth startup and rapid pressure build-up. This enables the emergency oil pump to achieve highly reliable pump start-up under safe current limits.

[0014] 2. This invention achieves dynamic correction of the oil column volume recovery process in vertical well riser by introducing continuous control logic based on negative volume area and a volume injection mechanism. When a volume deficit is detected in the oil column, a correction term is calculated based on the real-time measured pressure and flow rate relationship and superimposed on the target volume value. This allows each round of volume injection to adaptively compensate for the elastic deficit of the oil column, ensuring continuous oil column recovery. Through a logic gate signal setting mechanism, a safe state is automatically confirmed when the negative volume area returns to zero and the pump outlet pressure reaches the baseline value. This achieves a smooth switch between the soft start stage and the manual intervention stage, effectively avoiding overshoot, lag, or false triggering problems caused by conflicts between soft and hard control, and improving the coordination and controllability of the system response.

[0015] 3. This invention, by setting an injection volume update module and a volume correction ratio calculation mechanism in the control closed loop, can dynamically adjust the single injection volume according to the real-time flow resistance changes in the vertical shaft riser and the pressure difference before the valve. It realizes self-learning and self-correction of the multi-round volume injection process, ensuring that the oil column can maintain a stable oil replenishment rhythm under different temperatures, different oil viscosities, and different riser resistance conditions. It makes the output of the emergency oil pump and the flow response of the vertical shaft riser dynamically consistent, realizing the true integration of TRT soft start and hard manual emergency intervention. It not only improves the start-up reliability and response speed of the emergency oil pump system under extreme conditions, but also reduces the risk of equipment vibration and impact, ensuring the safe operation of large units and continuous oil pressure maintenance under abnormal conditions such as power failure and shutdown. Attached Figure Description

[0016] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a functional block diagram of a DC emergency oil pump control system that integrates TRT soft start and hard manual emergency intervention, provided in an embodiment of the present invention. Detailed Implementation

[0017] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0018] Example: This example provides a DC emergency oil pump control system that integrates TRT soft start and hard manual emergency intervention. See [link to example]. Figure 1 Specifically, including: The baseline pressure calculation module is used to calculate the baseline pressure value of the pressure oil in the vertical shaft riser of the lubrication system; In an embodiment of the present invention, calculating the baseline pressure value of the pressure oil in the lubrication system within the vertical shaft riser includes: To obtain the density of the pressurized oil in the lubrication system; Specifically, the lubrication system is comprehensively monitored and automatically managed by industrial control software. It is a complete oil supply and return device used to continuously supply pressurized oil to the main bearings, guide mechanisms, and other critical friction components within the underground plant. The industrial control software performs real-time data acquisition and logical control of the lubrication system's operating status, ensuring that the emergency oil pump or main oil pump can stably deliver the pressurized oil stored in the tank along the vertical shaft riser to the oil consumption point at the top of the equipment, forming a continuous oil column and maintaining the equipment's lubrication, cooling, and anti-wear operation. In special operating conditions such as system shutdown, black start, or abnormal fluctuations, the industrial control software maintains a minimum oil pressure through the emergency oil pump and automatically adjusts the oil pump start-up and shutdown strategy based on pressure, flow, and temperature feedback data, thereby preventing flow interruption, cavitation, or negative pressure sections in the vertical shaft riser oil column due to height differences. Through this intelligent control, the industrial control software can dynamically coordinate pump operation, power switching, and oil return balancing processes, ensuring that the lubrication system maintains continuous oil supply and stable pressure under various operating conditions, thus ensuring the safe, reliable, and efficient operation of the entire equipment during sudden shutdowns, power outages, or startup phases.

[0019] Specifically, industrial control software refers to automated software systems used for real-time monitoring, logical operations, and control decisions of multi-source physical quantities during equipment operation. This software collects key parameters such as pressure, flow rate, temperature, current, and voltage, and combines them with preset control algorithms and threshold rules to perform command scheduling and status feedback processing on actuators such as pumps, motors, and valves. Industrial control software not only has data acquisition and signal transmission functions, but also enables adaptive adjustment, status identification, and abnormal interlock protection of the operation process under complex working conditions. Its core function is to replace manual operation with software logic, achieving continuity, consistency, and accuracy in control logic, thereby improving system safety, response speed, and energy efficiency.

[0020] Obtain the vertical height difference of the shaft riser; Specifically, the vertical spatial arrangement of the riser pipe from the lower oil pump outlet connection to the upper equipment lubrication point is mapped. First, the vertical spatial distance from the bottom to the top of the riser pipe is collected at fixed points using a measuring ruler or laser rangefinder. The height values ​​of each segment are recorded one by one according to the actual layout sequence. Then, the height data of all segments are accumulated according to geometric relationships to obtain the overall vertical height difference between the bottom and top of the riser pipe. In scenarios where direct measurement is not possible, the elevation information provided by engineering design drawings, equipment layout drawings, or vertical shaft civil structure can be used to obtain the actual vertical height difference of the riser pipe by reading the elevation difference between the bottom control layer and the top equipment layer and combining it with the installation position of the riser pipe in the space. This ensures that the calculated height value can truly reflect the effective height of the oil column under the action of gravity in the vertical direction.

[0021] The hydrostatic pressure generated inside the vertical shaft riser due to the geometric height difference is obtained by multiplying the density of the pressurized oil, the vertical height difference of the riser, and the gravitational acceleration. Specifically, the reason why multiplying the density of the pressurized oil, the vertical height difference of the shaft riser, and the gravitational acceleration can yield the hydrostatic pressure generated by the geometric height difference within the shaft riser is that the pressure exerted by a static liquid in a gravitational field accumulates linearly with increasing vertical height. The pressure change is equal to the product of the mass of a unit volume of liquid and the gravitational acceleration, multiplied by the effective height of the liquid column. This relationship stems from the contribution of the liquid column's own weight to the pressure generated at the bottom in hydrostatics. Therefore, the density of the pressurized oil is used to characterize the mass of a unit volume of oil, the height difference of the shaft riser is used to characterize the effective height of the oil column, and the gravitational acceleration is used to characterize the magnitude of the gravity acting on the liquid. The product of these three factors directly yields the hydrostatic pressure formed by the height difference of the oil column, allowing the calculation result to accurately reflect the pressure distribution inside the shaft riser caused by the weight of the liquid column.

[0022] Specifically, the density of the pressure oil refers to the mass of the flowing pressure oil per unit volume in the lubrication system, and is a fundamental quantity used to characterize the magnitude of the static pressure generated by the oil under gravity in the vertical shaft riser; the vertical height difference of the vertical shaft riser refers to the geometric height interval between the bottom and top of the riser along the vertical direction, and is the main length parameter that determines the difference in gravitational potential energy borne by the oil column and forms the pressure head; gravitational acceleration refers to the fixed acceleration value exhibited by the oil under the downward pull in the Earth's gravitational field, and is used to calculate the pressure change caused by the weight of the oil column in the vertical direction; hydrostatic pressure refers to the pressure in the static state generated by the oil column in the vertical shaft riser due to the geometric height difference, and is a pressure quantity jointly determined by the pressure oil density, the vertical height difference of the riser, and gravitational acceleration.

[0023] Obtain the instantaneous volumetric flow rate through the vertical shaft riser; Specifically, when obtaining the instantaneous volumetric flow rate through the vertical shaft riser, firstly, a straight pipe section with a stable diameter, close to the outlet of the emergency oil pump, is selected on the vertical shaft riser. An electromagnetic flowmeter or turbine flowmeter, or other volumetric flow sensor, is reliably connected to the vertical shaft riser via a flange or welded short section, ensuring that the sensor's measuring chamber is connected to the pressure oil channel within the riser. During installation, the sensor is horizontally calibrated and fully checked according to the riser's axial direction. Subsequently, the electrical signal output terminal of the flow sensor is connected to a local signal conditioning unit. Signal stability is ensured through power supply, grounding, and shielded wiring. The signal conditioning unit then processes the voltage or current signal output by the sensor. The signal is amplified, filtered, and temperature compensated to convert it into a standard engineering quantity signal that corresponds one-to-one with the volumetric flow rate. Then, the standard engineering quantity signal is input to the acquisition module in the emergency oil pump control cabinet. The acquisition module periodically samples the signal according to a preset sampling period and, in conjunction with the range coefficient and calibration curve of the flow sensor, converts the sampled value into the volumetric flow rate value corresponding to the current sampling time in real time. Through the above installation, acquisition, and conversion process, the instantaneous volumetric flow rate of the pressurized oil flowing through the vertical shaft riser section can be obtained at each sampling time, thus providing an accurate flow input for subsequent calculation of friction pressure drop and baseline pressure value.

[0024] Multiply the preset friction coefficient by the square of the instantaneous volumetric flow rate to obtain the friction pressure drop of the pressurized oil. Specifically, the steps for generating the preset friction coefficient are as follows: First, during the system design phase, based on the construction drawings and shaft layout data of the vertical shaft riser, the geometric parameters of each section of the vertical shaft riser are statistically analyzed, including the nominal diameter, actual inner diameter, single section length, and fitting type of each pipe section. Pipe sections with different diameters, materials, and laying methods are numbered and recorded separately. Then, combining the pipe material manufacturer's instructions and inner wall treatment process, the corresponding pipe wall roughness parameters are retrieved or experimentally measured to characterize the friction conditions between the flowing oil and the pipe wall. Subsequently, within the expected operating oil temperature range, the density and dynamic viscosity of the pressure oil used in the lubrication system are experimentally measured or interpolated based on oil technical data to obtain the physical property parameters used to calculate the Reynolds number. Based on this, several representative volumetric flow rate conditions are selected, and pressure oil is delivered to the vertical shaft riser through an emergency oil pump or a test pump for commissioning. At each operating point, the pressure oil is utilized... The inlet and outlet pressure values ​​are simultaneously measured using pressure transmitters installed at the pump outlet and the upper end of the shaft. Combined with the vertical height difference of the shaft riser and the aforementioned hydrostatic pressure calculation results, the hydrostatic pressure is subtracted from the measured inlet and outlet pressure difference to obtain the frictional pressure drop caused by flow friction under this operating condition. Then, based on the approximate proportional relationship between the frictional pressure drop and the square of the volumetric flow rate, the frictional pressure drop at multiple operating points is used as the dependent variable, and the corresponding square of the volumetric flow rate is used as the independent variable. The proportionality coefficient is obtained using the linear least squares fitting method and defined as the frictional resistance coefficient of the shaft riser in this project. Finally, based on the oil temperature and flow rate fluctuations that may occur during the operation of the shaft riser, the fitted coefficient is safety-corrected and long-term operation-verified. The corrected coefficient is written into the parameter table of the emergency oil pump control device as the preset frictional resistance coefficient used in subsequent online calculations of frictional resistance pressure drop based on instantaneous volumetric flow rate.

[0025] The baseline pressure value of the pressurized oil in the vertical shaft riser is obtained by adding the hydrostatic pressure and the pressure drop due to friction along the shaft.

[0026] Specifically, instantaneous volumetric flow rate refers to the rate of volume change of pressurized oil through the riser cross-section per unit time at a certain sampling moment, reflecting the actual delivery intensity of the oil at that instant; friction coefficient refers to the comprehensive resistance parameter of energy loss caused by friction and pipe wall roughness during oil flow in the riser, the magnitude of which depends on the pipe material, inner wall condition, and oil flow state; friction pressure drop refers to the pressure loss caused by viscous friction and flow disturbance when the oil flows in the riser, and is the pressure drop after quantifying the friction coefficient and the kinetic energy term related to the flow rate; hydrostatic pressure refers to the pressure formed in the vertical direction by the weight of the oil column in the riser, used to characterize the gravitational pressure exerted on the bottom of the oil column in a static state; baseline pressure value refers to the stable pressure level formed by the hydrostatic pressure and friction pressure drop of pressurized oil in the riser under normal oil supply conditions, used to characterize the reference pressure value that the oil column should reach under given height and flow conditions.

[0027] Specifically, the pressure of the pressurized oil in the vertical shaft riser consists of two parts. One part is the hydrostatic pressure formed by the vertical height difference, which originates from the cumulative effect of the oil column's own weight in the vertical direction. The other part is the frictional pressure drop caused by the frictional resistance when the oil flows in the riser. This pressure drop usually follows the pipeline resistance calculation law based on the square of the flow rate. Therefore, by multiplying the preset frictional resistance coefficient by the square of the instantaneous volumetric flow rate, the pressure drop caused by flow loss can be obtained. Adding the hydrostatic pressure and the frictional pressure drop, we obtain the stable pressure level that the oil should have under the current geometric height and flow conditions. This pressure can reflect the basic pressure state of the vertical shaft riser under normal transportation conditions. Therefore, this calculation result is used as the baseline pressure value of the pressurized oil in the vertical shaft riser.

[0028] Specifically, calculating the baseline pressure value of the lubrication system oil in the vertical shaft riser is crucial for accurately identifying the potential alternating distribution of oil and gas within the riser during the early black start of an emergency pump. It also helps determine whether the current pressure change is solely due to the normal head generated by the shaft height difference and flow resistance. This is because when alternating oil plugs and cavities appear in the riser, a negative pressure segment forms inside the oil column, resulting in a negative slope for the pressure versus displacement change. Directly judging the oil volume state within the riser based on instantaneous fluctuations in pump outlet pressure is highly susceptible to errors due to gas compression and expansion. Expansion can cause misleading changes in the pressure curve, leading maintenance personnel to make incorrect judgments about pump output capacity or pipeline oil supply status. By calculating and obtaining the baseline pressure value that the vertical well riser should have under normal continuous oil column conditions in advance, a reliable reference can be provided for subsequent pressure changes. This allows the system to distinguish between normal pressure head changes and pressure drops caused by abnormal negative pressure sections, thereby accurately identifying early signs of negative pressure segment formation and avoiding misjudgments of pump-end failures or sudden pressure increases caused by manual forced cuts. This improves the reliability of judgment and the safety of control decisions during the black start process of an emergency oil pump.

[0029] Specifically, the negative section refers to the mixed section formed in the vertical well riser during the early black start of the oil pump due to the presence of compressible gas inside the oil column. This mixed section is composed of oil and gas in a segmented or flocculent distribution. Its overall compressibility is much higher than that of continuous oil, causing the volume of this section to be significantly compressed when subjected to pump end pressure. This results in an inverse relationship between the pressure change and the displacement change, manifested as an abnormal slope where the pressure increment decreases as the displacement increases. This abnormal response can reflect the presence of gas cavities or intermittent voids inside the oil column and is an important basis for judging the existence of discontinuous oil in the vertical well riser.

[0030] The negative body identification module is used to determine whether to generate the negative body area at the current moment based on the pump outlet pressure at the outlet of the emergency oil pump and the instantaneous volumetric flow rate of the vertical shaft riser. In an embodiment of the present invention, determining whether to generate a negative volumetric area quantity at the current moment based on the pump outlet pressure at the emergency oil pump outlet and the instantaneous volumetric flow rate of the vertical shaft riser includes: Obtain the pump outlet pressure at the outlet of the emergency oil pump; Specifically, the instantaneous pressure value of the pressurized oil at the pump outlet is collected in real time from a pressure sensor installed at the outlet of the emergency oil pump, and this pressure value is written into the data acquisition unit according to the sampling period to form a continuous pressure sequence. The pressure sensor is a measuring device rigidly connected to the pressurized oil pipeline. Each pressure value measured by the sensor corresponds to the pressurized state of the oil at the pump outlet at the current moment, and is used to describe the initial pressure of the pressurized oil before it is pumped into the vertical well riser. This process ensures that the original pressure source data of the emergency oil pump applied to the oil column is obtained.

[0031] Differential processing is performed on the two pump outlet pressures at adjacent sampling times to obtain the pressure increment of adjacent volume micro-segments; Specifically, after obtaining the continuous pump outlet pressure sequence, the pressure values ​​at two adjacent sampling times are differentially analyzed point by point. The pressure value at the later time is subtracted from the pressure value at the previous time to obtain the pressure change generated by the pressurized oil within that time interval, and this is used as the pressure increment of adjacent volume micro-segments. This pressure increment is used to describe the intensity of the change in the pressure state of the oil column within this small time interval, and can reflect the instantaneous compression or release of the compressible section under the drive of the pump outlet pressure. By adopting a pressure differential method with a fixed sampling period, the time consistency of the pressure increment calculation process can be ensured.

[0032] The instantaneous volumetric flow rate of the vertical shaft riser is integrated over time to obtain the cumulative discharge rate; Specifically, a volumetric flow rate measurement device is installed in the vertical shaft riser to collect the instantaneous volumetric flow rate of oil passing through the riser cross-section in real time, and the continuous instantaneous flow rate sequence is stored in the data acquisition unit according to the sampling period. Then, with a fixed sampling period as the step size, the instantaneous volumetric flow rate at each moment is integrated over time. The instantaneous flow rate value in the current sampling period is multiplied by the time length of the period and then added to the cumulative result of the previous period to finally form the cumulative discharge in the vertical shaft riser at the current moment. This cumulative discharge represents the total volume of oil pump input into the vertical shaft riser since the emergency pump was started, and can be used to characterize the volume evolution of oil column propulsion inside the vertical shaft riser.

[0033] Specifically, the pump outlet pressure at the outlet of the emergency oil pump refers to the instantaneous pressure value formed at the pump outlet when the emergency oil pump delivers pressurized oil to the vertical shaft riser. This pressure value reflects the instantaneous driving force level applied by the pump end to the entire oil column. The pressure increment of adjacent volume segments refers to the local pressure change obtained by the pump outlet pressure difference at two consecutive sampling times. It is used to characterize the response change of the oil column within a very short time scale, thereby characterizing the compressibility of the oil and entrained gas mixture in this small volume segment. The instantaneous volumetric flow rate of the vertical shaft riser refers to the volume of pressurized oil passing through the cross-section of the vertical shaft riser per unit time. It is a core flow parameter for measuring the oil column movement speed and oil delivery efficiency. The cumulative discharge refers to the total volume of pressurized oil delivered after integrating the instantaneous volumetric flow rate over time. This volume reflects the overall level of the actual amount of oil replenished by the pump end to the vertical shaft riser.

[0034] The cumulative displacement at two adjacent sampling times is differentially processed to obtain the displacement increment of adjacent volume micro-segments; The ratio of the pressure increment to the displacement increment of adjacent volume micro-segments is calculated to obtain discrete ratios; Specifically, after obtaining the continuous cumulative displacement sequence within the vertical shaft riser, the cumulative displacement values ​​at two adjacent sampling times are selected and differentially analyzed point by point. The cumulative displacement at the later time is subtracted from the cumulative displacement at the previous time to obtain the displacement increment corresponding to the adjacent volume micro-segment, which is used to characterize the actual propulsion volume change of the oil column within this small time interval. Subsequently, the pressure increment of the aforementioned adjacent volume micro-segment is compared with the displacement increment of the same volume micro-segment to establish a correspondence between the pressure change and the volume change within the same micro-segment, thereby obtaining a discrete ratio reflecting the local compressibility characteristics of the oil column. The above processing obtains a differential component by differential analysis of the cumulative amount and normalizes it in the form of a ratio.

[0035] Specifically, the two cumulative displacements at adjacent sampling moments refer to the statistical values ​​of the total pressure oil volume passing through the riser section at two consecutive sampling moments, reflecting the overall transport progress of the oil column within that time period; the displacement increment of adjacent volume segments refers to the volume change obtained by differentiating the two cumulative displacements, which characterizes the instantaneous volume replenishment level of the oil column advancing into the riser in a very short time; the pressure increment of adjacent volume segments refers to the pressure change obtained by differentiating the pressure values ​​at the outlet of the emergency pump at the same pair of adjacent sampling moments, which reflects the strength of the compressible response generated by the compressible section inside the oil column in a short time; the discrete ratio refers to the value obtained by comparing the pressure increment and displacement increment of adjacent volume segments, used to describe the response correspondence between pressure change and volume change, thereby characterizing the transient state characteristics of the compressible section in the oil column.

[0036] Obtain the negative volume area of ​​the vertical shaft oil column in the vertical shaft riser at the previous moment; If all discrete ratios are greater than 0, the negative volume area of ​​the previous time step remains unchanged; otherwise, the negative volume area of ​​the previous time step is updated to obtain the negative volume area of ​​the current time step.

[0037] Specifically, firstly, the negative volume area of ​​the vertical shaft oil column in the riser at the previous moment is obtained as the basis for judging the elastic deficit state of the oil column at the current moment. Then, the discrete ratio of all volume micro-segments at the current moment is judged. If all discrete ratios are greater than zero, it means that the current pressure and displacement relationship has not changed in reverse, and no new deficit area has been generated in the oil column. Therefore, the negative volume area at the previous moment is kept unchanged so that the negative volume area remains stable when there is no pressure drop anomaly. If the discrete ratio of any volume micro-segment is less than zero, it means that the oil column has a reverse response of pressure drop relative to displacement change in that micro-segment, forming a new elastic deficit area. Therefore, the negative volume area at the previous moment is accumulated and updated based on the area of ​​the identified negative slope volume segment so that the negative volume area can accurately include the newly added deficit volume at the current moment, thereby obtaining the negative volume area at the current moment, which is used for subsequent volume compensation control and valve logic judgment.

[0038] Specifically, when all discrete ratios are greater than 0, it indicates that there are no negative slope segments within the current volume range where pressure decreases with displacement, and no new volume deficits appear within the oil column. This means that the volume continuity is maintained perfectly normally within the current cycle. Therefore, there is no need to update the negative volume area from the previous moment; the negative volume area from the previous moment should be used as the negative volume area for the current moment. In this case, the subsequent steps can continue, such as volume injection judgment, volume target calculation, or logic gate setting. The negative volume area remains unchanged as the input for the subsequent steps, thus ensuring that the entire control logic operates smoothly without introducing unnecessary correction operations when the oil column continuity is stable.

[0039] Specifically, the negative volume area refers to the cumulative volume area of ​​the compressible contraction region of the oil column in the riser due to the decrease in internal pressure. This value is used to characterize the degree of volume deficiency of the oil column under pressure drop. Due to the geometric constraints of the riser, the oil column will undergo compressible contraction when the pressure decreases, causing the volume change to appear as a concave area with a slope lower than the baseline in the pressure-volume relationship diagram. The negative volume area is obtained by integrating the area of ​​this concave area, which is used to characterize the volume loss inside the oil column caused by elastic compression.

[0040] In an embodiment of the present invention, updating the negative volume area at the previous moment to obtain the negative volume area at the current moment includes: The minimum value of the discrete ratio is compared with 0 to obtain the negative slope ratio. The area of ​​the negative slope volume segment is obtained by multiplying the negative slope ratio and the displacement increment of the adjacent volume micro-segment. The area of ​​all negative slope volume segments is summed to obtain the summation result; The difference between the negative volume area at the previous moment and the accumulated result is calculated to obtain the negative volume area at the current moment.

[0041] Specifically, the discrete ratio refers to the numerical proportion between the pressure increment and the displacement increment within adjacent volume segments. This ratio reflects the pressure response trend of the oil column under small volume changes. The negative slope ratio is the result obtained by comparing the discrete ratio with the minimum value of zero, used to extract the reverse change portion where the pressure decreases as the volume increases. The negative slope volume segment area is the value obtained by multiplying the negative slope ratio with the corresponding displacement increment. This value reflects the comprehensive influence of the reverse pressure change in this volume segment. The cumulative result of all negative slope volume segment areas is the overall deviation obtained by summing the negative slope area in all volume segments. This value is used to characterize the pressure drop deficit of the entire oil column at the current moment. The negative volume area at the current moment is the elastic deficit volume of the oil column obtained by calculating the difference between the negative volume area at the previous moment and the cumulative result. This value is used to describe the overall compressible zone size formed inside the oil column due to the reverse pressure response.

[0042] Specifically, the process involves comparing the discrete ratio to its minimum value with zero and extracting the portion less than zero. This is based on the fundamental response relationship between pressure and volume changes, identifying all segments exhibiting a decrease in pressure and an increase in volume. Next, the negative slope ratio is multiplied by the displacement increment of the corresponding micro-segment. This is based on infinitesimal multiplication, accumulating the reverse pressure response within each small segment into a quantifiable area value. Further summing the area values ​​of all negative slope volume segments integrates the reverse responses within all micro-segments along the entire vertical well column to obtain the total pressure deficit area. Finally, subtracting the current accumulated result from the previous negative volume area yields the unrecovered elastic deficit volume within the oil column at the current moment, based on the recoverability of pressure deficit over time, through difference calculation. The resulting value is the current negative volume area, reflecting the overall deficit degree within the oil column caused by the lag in pressure backfilling.

[0043] The continuous control module is used to continuously control the operating status of the emergency oil pump based on the current negative volume area. In an embodiment of the present invention, the operating status of the emergency oil pump is continuously controlled based on the current negative volume area, including: The volume of a single injection is calculated by multiplying the inner diameter cross-sectional area of ​​the shaft riser and the lifting height of the shaft riser. Specifically, the single injection volume refers to the planned increase in volume to be added to the vertical shaft riser in the current round of volume injection. This volume is calculated based on the riser cross-sectional area and the designed lifting height, and is used to achieve segmented lifting control of the oil column.

[0044] The correction term is calculated based on the negative volume area at the current moment, and the formula for calculating the correction term is as follows:

[0045] In the formula, It is a correction item. It is the negative volume area at the current moment. It is the inner diameter and cross-sectional area of ​​the shaft riser. It is the density of the pressurized oil. It is gravitational acceleration; Specifically, the riser inner diameter cross-sectional area refers to the effective flow cross-sectional area inside the riser, which characterizes the space occupied by the pressurized oil in the riser; the pressurized oil density refers to the mass per unit volume of the pressurized oil, which determines the static pressure distribution of the oil column in the gravitational field; gravitational acceleration refers to the acceleration of the pressurized oil under the influence of Earth's gravity, which is a necessary gravity parameter when converting the negative volume area into an equivalent volume correction; the correction term refers to the volume compensation amount calculated based on the current negative volume area, which is used to compensate for the actual injection deficiency caused by the elasticity loss of the oil column, thereby ensuring that the target of subsequent volume injection is closer to the actual needs.

[0046] Specifically, the correction term is calculated by multiplying the negative volume area by the cross-sectional area of ​​the riser's inner diameter and dividing by the product of the pressure oil density and gravitational acceleration. This is based on the conversion rule between static pressure and liquid column height. The negative volume area represents the effective pressure deficit appearing on the pressure-volume relationship curve, and its value is equivalent to the pressure gap formed in the riser due to the elastic compression of the oil column, residual gas, or structural rebound. According to the law that static pressure is proportional to liquid column height, the equivalent liquid column height corresponding to the same pressure deficit can be calculated using the pressure oil density and gravitational acceleration. Then, the cross-sectional area of ​​the riser's inner diameter is used to convert this equivalent height into an equivalent volume. Thus, the product of the negative volume area and the inner diameter provides the equivalent volume increase requirement, while the combination of density and gravitational acceleration provides the conversion coefficient for the pressure-liquid column height relationship. The final correction term accurately describes the minimum additional volume required to compensate for the pressure deficit, ensuring that the volume injection process can truly restore the pressurized state of the riser oil column.

[0047] The cumulative discharge volume, single injection volume, and correction items of the vertical shaft riser at the current moment are added together to obtain the target volume value; Specifically, the target volume value is calculated by adding the cumulative displacement of the riser at the current moment, the single injection volume, and the correction term. This is based on the continuous conservation relationship of the riser oil column volume change. The cumulative displacement represents the total volume actually pushed into the riser by the pump before the current moment, reflecting the basic state of the current oil column volume inside the riser. The single injection volume is the designed injection volume to be added to the riser in this volume package, the purpose of which is to achieve a regular step-like increase in oil column volume under normal operating conditions. The correction term reflects the additional equivalent volume required due to pressure gaps or oil column elasticity effects, used to compensate for the volume voids formed by transient pressure loss in the oil column, so that the oil column returns to the proper pressurized height. Therefore, combining the above three parts is equivalent to fully compensating for the riser oil column volume, so that the calculation result includes the injected volume, the planned injected volume, and the necessary pressure compensation volume. The resulting volume target value is the total oil volume target required to make the riser reach a stable pressurized state, thus providing a clear volume benchmark for the continuous control of the operation status of the emergency oil pump.

[0048] Specifically, the cumulative discharge of the riser at the current moment refers to the total volume of oil pump that has been pumped upward through the riser since the emergency pump started. This volume is obtained by continuously integrating the instantaneous volumetric flow rate and is used to reflect the overall degree to which the oil column has been pushed up in the riser. The target volume value refers to the target volume increase for the next stage formed after considering the cumulative discharge, single injection volume, and correction items. This target value is used as an immediate reference for pump control actions. The continuous control of the emergency pump's operating status refers to using the target volume value as a constraint and adjusting the pump's start-up, shutdown, or operating rhythm to dynamically approach the target volume change in the riser, thereby ensuring that the oil column is lifted segment by segment according to design requirements.

[0049] The operating status of the emergency oil pump is continuously controlled based on the target volume value.

[0050] Specifically, when continuously controlling the operating status of the emergency oil pump based on the volume target value, the volumetric flow rate measuring device and speed detection device installed on the vertical shaft riser first send the current instantaneous volumetric flow rate and the operating status signal of the emergency oil pump to the control unit in real time. The control unit performs numerical integration of the instantaneous volumetric flow rate according to a preset sampling period, continuously updates the cumulative discharge of the vertical shaft riser at the current moment, and compares the cumulative discharge with the aforementioned volume target value in each sampling period. If the cumulative discharge is less than the volume target value, the emergency oil pump is kept in operation without changing the original motor protection and soft start current limiting strategy, by adjusting the DC voltage output duty cycle or the contactor conduction time. The actual output capacity of the pump is kept stable within the allowable range. When the comparison results show that the cumulative displacement is gradually approaching the target volume value, the control unit appropriately reduces the drive duty cycle of the emergency oil pump or extends the stop interval according to the degree of approach, so that the cumulative displacement approaches the target volume value in a slow manner, thereby reducing volume overshoot. Once the cumulative displacement is detected to reach or slightly exceed the target volume value, the control unit immediately issues a pump stop command or switches to pressure holding mode to keep the emergency oil pump stopped or running at low power. At the same time, the control unit locks the end flag of this round of control and prepares to enter the next round of volume package calculation, so that the start-up and shutdown process of the emergency oil pump is always constrained by the target volume value, thereby realizing continuous and precise control of the riser oil column lifting process in the vertical well.

[0051] Specifically, the continuous control of the operation status of the emergency oil pump based on the target volume value is because when the emergency oil pump injects pressurized oil into the vertical shaft riser, its displacement change will not always remain linear. During the lifting process, the oil column in the vertical shaft riser will be affected by gravity, friction resistance, and the complex geometry of the wellbore. If the emergency oil pump is controlled by a fixed time or a fixed speed, it is very easy to have insufficient oil injection, resulting in the oil column not being able to be lifted continuously, or excessive oil injection, resulting in instantaneous overshoot of the oil column. This will cause unstable states such as gas-liquid stratification, oil column breakage, or abnormal impact pressure in the vertical shaft riser. By calculating the target volume value, the current cumulative discharge, single injection volume, and correction terms obtained based on the negative volume area are comprehensively quantified to form a target volume that can truly reflect the oil column lifting requirements in the vertical shaft riser. The control system dynamically adjusts the output of the emergency oil pump based on this target volume value, so that the pump operation process is always consistent with the actual replenishment volume required by the oil column, ensuring that the oil column rises continuously and uniformly, avoiding problems such as fluid column interruption, pressure surge, or system over-replenishment, thereby maintaining the overall stability and continuity of the oil column in the vertical shaft riser, and providing a reliable pressure and volume basis for subsequent steps such as negative volume area detection and gate signal determination.

[0052] The gate signal setting module is used to set the logic gate signal between the emergency oil pump and the vertical shaft riser based on the current negative body area and the pump outlet pressure at the emergency oil pump outlet after the continuous control ends. In an embodiment of the present invention, the logic gate signal between the emergency oil pump and the vertical shaft riser is set based on the current negative volume area and the pump outlet pressure at the emergency oil pump outlet, including: If the negative volume area is 0 at the current moment and the pump outlet pressure at the emergency pump outlet is greater than or equal to the baseline pressure value, then the logic gate signal between the emergency pump and the vertical shaft riser is set to 1; otherwise, the logic gate signal is set to 0.

[0053] Specifically, the above judgment logic is based on whether the oil column has been completely replenished and a stable pressure head has been established to determine the connection status between the emergency oil pump and the vertical shaft riser. When the negative volume area is equal to zero at the current moment, it indicates that through the aforementioned volume injection and correction compensation, the volume loss in the vertical shaft riser originally caused by gas entrainment or elastic compression has been completely eliminated, and the oil column has recovered from segmented oil body to a continuous whole. At this time, it is then checked whether the pump outlet pressure at the emergency oil pump outlet is greater than or equal to the baseline pressure value. If the pump outlet pressure reaches or exceeds the baseline level determined by the hydrostatic pressure and friction resistance, it indicates that the vertical shaft riser has not only been replenished in volume but also that the connection status between the emergency oil pump and the vertical shaft riser has been established. There is no deficit, and the pressure head along the pipeline has been established to the normal operating range. The pipeline is capable of withstanding soft start and hard manual operation switching. Therefore, the logic gate signal between the emergency oil pump and the vertical shaft riser is set to one, allowing the system to enter the next stage of connection or switching. Conversely, as long as the negative volume has not been eliminated or the pump outlet pressure has not returned to the baseline level, it indicates that there may still be hidden gas chambers or insufficient pressure head in the oil column. Keeping the logic gate signal at zero can prevent the unstable oil column from being mistakenly regarded as a safe state, thereby avoiding premature valve switching or load integration before the oil column has fully recovered, which could lead to shock pressure, flow interruption, or equipment failure.

[0054] Specifically, volumetric injection refers to the process of replenishing a fixed volume of pressurized oil into the riser in batches using an emergency pump when a volume deficit occurs. This gradually fills the gaps in the oil column caused by gas entrainment, elastic compression, or flow fluctuations, thus restoring the oil column from a segmented state to a continuous column. In this process, each fixed volume of oil replenished is considered an independent volume unit. These volume units accumulate sequentially within the riser, gradually restoring the overall volume, pressure head, and continuity of the oil column to normal. This process is called volumetric injection.

[0055] Specifically, the reason why, after continuous control ends, it is necessary to set the logic gate signal between the emergency pump and the wellbore riser based on the current negative volume area and the pump outlet pressure at the emergency pump outlet is that the volume injection process is essentially an oil column continuity restoration operation. Its ultimate goal is to determine whether the oil column has recovered from segmented oil bodies to a stable continuous oil column. The negative volume area directly characterizes whether there is still a volume deficit inside the oil column, while the pump outlet pressure reflects whether a stable pressure baseline has been established. When the negative volume area drops to zero and the pump outlet pressure reaches or exceeds the baseline pressure value, it indicates that the oil column continuity has been restored, and oil flow should be allowed to re-enter the wellbore riser. Therefore, the logic gate signal is set to one. Conversely, if either condition is not met, the oil column still faces the risk of fracture, and the gate must be kept closed to avoid the formation of miscible backflow or pressure instability. Thus, the final confirmation of the system's safe state is achieved through the setting of the logic gate signal.

[0056] The injection volume update module is used to calculate and update the single injection volume after the signal setting is completed; In an embodiment of the present invention, calculating and updating the single injection volume includes: The instantaneous volumetric flow rate at two adjacent sampling times is differentially processed to obtain the instantaneous flow rate change; Calculate the pressure difference before the valve of the pre-regulating valve in the vertical shaft riser; Specifically, when calculating the pressure difference before the pre-control valve in the vertical shaft riser, a pressure sensor is first installed in the straight pipe section upstream of the pre-control valve in the vertical shaft riser. Through an electrical signal connection with the data acquisition unit, the original pressure and voltage signals at this measurement point are continuously acquired within a preset sampling period. The voltage value is then converted into an instantaneous in-valve pressure measurement value in engineering quantity form according to the sensor calibration curve. Simultaneously, the control unit reads the baseline pressure value of the vertical shaft riser obtained from the aforementioned hydrostatic pressure and friction resistance calculation steps. This baseline pressure value is used as the reference pressure that should be present before the valve when the oil column is continuous and there is no abnormal obstruction. Subsequently, the control unit performs a numerical subtraction operation between the in-valve pressure measurement value at the same sampling moment and the baseline pressure reference value. The sign and magnitude of the difference reflect the degree to which the in-valve pressure is higher or lower than the theoretical baseline, as well as the magnitude of the deviation. The calculated difference is recorded as the in-valve pressure difference value at that sampling moment.

[0057] The current response ratio is obtained by calculating the ratio of the instantaneous flow rate change to the pressure difference before the valve. Specifically, the instantaneous flow rate change refers to the change in flow rate per unit time between two adjacent sampling moments, obtained by differential calculation of the volumetric flow rate at the previous and subsequent moments. This quantity reflects the changing trend of the fluid flow intensity in the vertical shaft riser. The pressure difference before the valve refers to the pressure difference between two measuring points before and after the pre-regulating valve in the vertical shaft riser. This difference reflects the pressure drop intensity caused by throttling or resistance of the fluid before the valve and is a key quantity for judging the current trend of flow resistance change. The current response ratio is the quantity obtained by calculating the ratio of the instantaneous flow rate change to the pressure difference before the valve. This ratio reflects the response speed of the flow change relative to the pressure change at the current node. This response ratio can be used to further determine whether there is abnormal stagnation, sudden acceleration or other changes in flow state in the system at the current moment.

[0058] Specifically, in the calculation of the relationship between instantaneous flow rate and inlet pressure change, the process first involves differential calculation of two instantaneous volumetric flow rate values ​​output by the flow sensor in the vertical shaft riser at adjacent sampling times. The instantaneous flow rate change is obtained by subtracting the instantaneous volumetric flow rate at the previous moment from the instantaneous volumetric flow rate at the next moment, reflecting the increase or decrease in fluid flow across the cross-section within a very short time interval. Subsequently, continuous pressure records from the inlet pressure sensor located at the pre-regulating valve are collected, and the inlet pressure values ​​at adjacent sampling times are subtracted to obtain the amplitude of inlet pressure change at this small time scale, reflecting pressure fluctuations caused by changes in fluid resistance or flow channel opening. After obtaining the instantaneous flow rate change and the inlet pressure difference, a ratio is calculated between the two, using the instantaneous flow rate change as the numerator and the inlet pressure difference as the denominator, to obtain the current response ratio. This ratio characterizes the actual flow response amplitude caused by a unit change in inlet pressure, thus providing accurate basic data for subsequent judgment of the dynamic response deviation of the vertical shaft riser system and correction of the injection volume.

[0059] Divide the baseline response ratio of the vertical shaft riser by the current response ratio to obtain the volume correction ratio. Specifically, the process for generating the baseline response ratio of the vertical shaft riser is as follows: First, the emergency oil pump, vertical shaft riser, and pre-regulating valve are placed in a structurally intact and fault-free state. The lubricating oil is circulated according to the design conditions for a period of time to stabilize the oil temperature within the specified range. Air is repeatedly released through the vent valve until no visible air bubbles remain in the vertical shaft riser, thus obtaining a continuous oil column. Then, the opening of the pre-regulating valve is fixed at a nominal working position. The drive voltage of the emergency oil pump is increased or decreased in a stepwise manner through a motor control device. After each stepwise change, a constant time is maintained to allow the flow rate and pressure to enter a new stable range. Within each stable range, the volumetric flow rate sensor installed on the vertical shaft riser is used to collect data. Multiple sets of instantaneous volumetric flow rate data were collected, along with multiple sets of inlet pressure data collected by pressure sensors placed in front of the pre-regulating valve during the same time period. The average volumetric flow rate of two adjacent stable intervals was then differentially calculated to obtain the flow rate change corresponding to the step test. Similarly, the average inlet pressure of two adjacent stable intervals was differentially calculated to obtain the corresponding inlet pressure change. The flow rate change for each test was divided by the inlet pressure change to obtain a set of test response ratios. After completing multiple repeated tests with different step amplitudes and flow ranges, outliers were removed from all test response ratios, and an arithmetic mean was applied. The resulting average response ratio was used as the baseline response ratio for the vertical shaft riser.

[0060] The volume of a single injection is updated based on the volume correction ratio to obtain the updated volume of a single injection.

[0061] Specifically, after obtaining the volume correction ratio, the volume of a single injection is updated using the volume correction ratio as an adjustment coefficient. The single injection volume is multiplied by the volume correction ratio to obtain the updated single injection volume. This allows the injection volume to be corrected in real time according to dynamic conditions such as changes in resistance within the vertical shaft riser, gas entrainment, and fluctuations in valve opening, thereby ensuring the accuracy and continuous stability of volume compensation control.

[0062] Specifically, the reference response ratio of the vertical shaft riser refers to the reference ratio between the unit change in pre-valve pressure and the unit change in flow rate, determined through experiments during the commissioning or stable operation phase of the equipment. It is used to characterize the standard response relationship between pressure and flow rate of the vertical shaft riser under healthy operating conditions. The volume correction ratio refers to the ratio obtained by dividing the reference response ratio of the vertical shaft riser by the current response ratio. This ratio is used to measure the degree of deviation of the current pressure and flow response from the standard state, thereby calculating the injection volume multiplier that needs to be increased or decreased. The single injection volume refers to the basic volume volume to be added in each round of volume pack injection without correction. The updated single injection volume refers to the corrected volume volume obtained by multiplying the basic single injection volume by the volume correction ratio. It is used to automatically compensate for the vertical shaft riser response deviation in the next round of volume pack injection, so that the actual injection volume is consistent with the expected pressure and flow response.

[0063] Specifically, updating the single-injection volume using a volume correction ratio is necessary because the actual operation of the riser is affected by objective factors such as oil temperature changes, pipe wall roughness changes, trace gas entrainment in the oil, and valve opening / closing status deviations, causing the actual injection volume at the same pump outlet pressure to differ from the design volume. To avoid systematic deviations caused by long-term use of the initial nominal value for single-injection volumes, the control system calculates the ratio of the baseline response ratio to the current response ratio, thereby quantifying the degree of deviation of the current flow state of the riser from the baseline state. This deviation is then used to proportionally adjust the initial single-injection volume, ensuring that the updated single-injection volume reflects the true delivery capacity of the riser under the current oil temperature, current pressure difference, and current flow resistance characteristics. In this way, each injection operation is based on the real-time corrected volume, ensuring the accuracy of cumulative volume calculation and providing a stable and reliable volume basis for subsequent negative volume determination and logic gate control. Therefore, this process yields the updated single-injection volume.

[0064] The next injection initialization module is used to inject the next volume package into the emergency oil pump based on the updated single injection volume.

[0065] In an embodiment of the present invention, the next round of volumetric injection into the emergency oil pump based on the updated single injection volume includes: The target volume value is updated based on the updated single injection volume to obtain the updated target volume value. The next round of volumetric injection is performed on the emergency oil pump based on the updated target volume value.

[0066] Specifically, during the process of updating the volume target value based on the updated single injection volume, the control unit first retrieves the previously accumulated cumulative displacement data within the riser and simultaneously obtains the volume compensation value obtained from the previous round of volume correction calculation. Then, the cumulative displacement and the volume compensation value are added sequentially to obtain the reference volume that the current oil column should reach before this round of volumetric injection. Next, this reference volume is added to the updated single injection volume to obtain the latest volume target value that should be reached within the riser at the end of this round of injection.

[0067] Specifically, when injecting the emergency pump with the updated volumetric target value for the next round of volumetric injection, the current volumetric target value is first read as the control threshold for this round. Simultaneously, the vertical shaft riser discharge baseline recorded at the end of the previous round is restored, ensuring continuous discharge accumulation calculation. A start command is sent to the emergency pump, initiating the injection of pressurized oil into the vertical shaft riser according to a predetermined start-stop strategy. Throughout the injection process, the flow measurement device continuously acquires the instantaneous volumetric flow rate flowing through the vertical shaft riser at fixed sampling intervals. This data is then accumulated over time to obtain the real-time discharge rate. This real-time discharge rate is compared with the volumetric target value. When the real-time discharge rate reaches or exceeds the volumetric target value for the first time, a stop command is immediately issued to the emergency pump, ending the current round of volumetric injection.

[0068] Specifically, to ensure that the oil column volume in the riser gradually approaches a stable state according to actual operating conditions, after completing the previous round of volume calculation and correction, the updated single-injection volume should be used as the basis for the next round of volumetric injection. This ensures that the compensation amount undertaken by the emergency oil pump in each injection round remains consistent with real-time displacement and pressure changes. Since the oil column in the riser is continuously affected by leakage, compressibility changes, and flow resistance during its ascent, continuing to use the old or empirical injection volume will lead to insufficient or excessive injection, making it difficult to maintain a controllable oil column height. By executing the next round of volumetric injection based on the updated single-injection volume, each injection closely matches the previous round's correction results, creating a closed-loop regulation process. This allows the oil column to gradually approach the target volume while avoiding oscillations and accumulated deviations, thereby ensuring a stable oil replenishment rhythm and controllable pressure response during emergency oil replacement in the riser, improving overall operational safety and reliability.

[0069] Specifically, this invention achieves integrated control of the DC emergency oil pump by constructing an adaptive control process for the oil column status in the vertical shaft riser based on industrial control software, combining TRT soft start and manual emergency intervention. The industrial control software uses real-time collected pump outlet pressure, riser flow, and volume change data as input to establish a data-driven dynamic monitoring model. It judges the continuity of the oil column in the vertical shaft riser and automatically generates control commands based on system response characteristics. During system startup, the industrial control software controls the TRT soft starter to smoothly drive the emergency oil pump to increase speed in a current-limiting manner. By calculating the negative volume area and baseline pressure value, it determines whether there is elastic collapse or liquid plugging fault in the oil column and generates a correction volume in real time based on the judgment result. This ensures that the current change rate of the TRT soft starter output remains dynamically consistent with the oil column volume recovery process, thereby avoiding pressure drops or flow interruptions during the initial pressurization phase. When the negative volume is detected to be zero and the pump outlet pressure reaches the baseline pressure value, the industrial control software automatically triggers the logic gate signal judgment process to confirm the oil column filling and the stable recovery state of the shaft fluid. It then sets the logic gate signal of the manual intervention channel to the open state, allowing uninterrupted manual operation to access the system control loop. During normal operation, the industrial control software corrects and records the injection volume of each round of volumetric pumps. Combining the friction resistance and pressure fluctuation characteristics within the shaft riser, it dynamically updates the target volume value, achieving adaptive volumetric pump injection control for emergency pumps. When the system enters an abnormal state or communication lag occurs, the manual intervention loop can immediately take over under the guidance of the status signal generated by the industrial control software, achieving continuous fusion and complementary control of the soft start logic and manual intervention logic. Through the above design, this invention utilizes industrial control software to achieve collaborative decision-making and closed-loop regulation of both soft and hard control modes. This ensures both the safety and stability of the TRT soft start process and guarantees rapid and accurate manual intervention in the event of a sudden failure, thereby significantly improving the response speed, pressure recovery efficiency, and overall operational reliability of the DC emergency pump system under extreme conditions.

[0070] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A DC emergency oil pump control system integrating TRT soft start and hard manual emergency intervention, characterized in that, include: The baseline pressure calculation module is used to calculate the baseline pressure value of the pressure oil in the vertical shaft riser of the lubrication system; The negative body identification module is used to determine whether to generate the negative body area at the current moment based on the pump outlet pressure at the outlet of the emergency oil pump and the instantaneous volumetric flow rate of the vertical shaft riser. The continuous control module is used to continuously control the operating status of the emergency oil pump based on the current negative volume area. The gate signal setting module is used to set the logic gate signal between the emergency oil pump and the vertical shaft riser based on the current negative body area and the pump outlet pressure at the emergency oil pump outlet after the continuous control ends. The injection volume update module is used to calculate and update the single injection volume after the signal setting is completed; The next injection initialization module is used to inject the next volume package into the emergency oil pump based on the updated single injection volume.

2. The DC emergency oil pump control system integrating TRT soft start and hard manual emergency intervention as described in claim 1, characterized in that, Calculate the baseline pressure value of the pressurized oil in the lubrication system within the vertical shaft riser, including: To obtain the density of the pressurized oil in the lubrication system; Obtain the vertical height difference of the shaft riser; The hydrostatic pressure generated inside the vertical shaft riser due to the geometric height difference is obtained by multiplying the density of the pressurized oil, the vertical height difference of the riser, and the gravitational acceleration. Obtain the instantaneous volumetric flow rate through the vertical shaft riser; Multiply the preset friction coefficient by the square of the instantaneous volumetric flow rate to obtain the friction pressure drop of the pressurized oil. The baseline pressure value of the pressurized oil in the vertical shaft riser is obtained by adding the hydrostatic pressure and the pressure drop due to friction along the shaft.

3. The DC emergency oil pump control system integrating TRT soft start and hard manual emergency intervention as described in claim 1, characterized in that, Determining whether to generate a negative volumetric area quantity at the current moment based on the pump outlet pressure at the accident oil pump outlet and the instantaneous volumetric flow rate of the vertical shaft riser includes: Obtain the pump outlet pressure at the outlet of the emergency oil pump; Differential processing is performed on the two pump outlet pressures at adjacent sampling times to obtain the pressure increment of adjacent volume micro-segments; The instantaneous volumetric flow rate of the vertical shaft riser is integrated over time to obtain the cumulative discharge rate; The cumulative displacement at two adjacent sampling times is differentially processed to obtain the displacement increment of adjacent volume micro-segments; The ratio of the pressure increment to the displacement increment of adjacent volume micro-segments is calculated to obtain discrete ratios; Obtain the negative volume area of ​​the vertical shaft oil column in the vertical shaft riser at the previous moment; If all discrete ratios are greater than 0, the negative volume area of ​​the previous time step remains unchanged; otherwise, the negative volume area of ​​the previous time step is updated to obtain the negative volume area of ​​the current time step.

4. The DC emergency oil pump control system integrating TRT soft start and hard manual emergency intervention as described in claim 3, is characterized in that, Update the negative volume area from the previous time step to obtain the negative volume area at the current time step, including: The minimum value of the discrete ratio is compared with 0 to obtain the negative slope ratio. The area of ​​the negative slope volume segment is obtained by multiplying the negative slope ratio and the displacement increment of the adjacent volume micro-segment. The area of ​​all negative slope volume segments is summed to obtain the summation result; The difference between the negative volume area at the previous moment and the accumulated result is calculated to obtain the negative volume area at the current moment.

5. The DC emergency oil pump control system integrating TRT soft start and hard manual emergency intervention as described in claim 2, characterized in that, Based on the current negative volume area, the operating status of the emergency oil pump is continuously controlled, including: The volume of a single injection is calculated by multiplying the inner diameter cross-sectional area of ​​the shaft riser and the lifting height of the shaft riser. The correction term is calculated based on the negative volume area at the current moment; The cumulative discharge volume, single injection volume, and correction items of the vertical shaft riser at the current moment are added together to obtain the target volume value; The operating status of the emergency oil pump is continuously controlled based on the target volume value.

6. The DC emergency oil pump control system integrating TRT soft start and hard manual emergency intervention as described in claim 1, characterized in that, Based on the current negative volume area and the pump outlet pressure at the emergency pump outlet, the logic gate signal between the emergency pump and the vertical shaft riser is set, including: If the negative volume area is 0 at the current moment and the pump outlet pressure at the emergency pump outlet is greater than or equal to the baseline pressure value, then the logic gate signal between the emergency pump and the vertical shaft riser is set to 1; otherwise, the logic gate signal is set to 0.

7. The DC emergency oil pump control system integrating TRT soft start and hard manual emergency intervention as described in claim 5, is characterized in that, Calculate the volume of a single injection update, including: The instantaneous volumetric flow rate at two adjacent sampling times is differentially processed to obtain the instantaneous flow rate change; Calculate the pressure difference before the valve of the pre-regulating valve in the vertical shaft riser; The current response ratio is obtained by calculating the ratio of the instantaneous flow rate change to the pressure difference before the valve. Divide the baseline response ratio of the vertical shaft riser by the current response ratio to obtain the volume correction ratio. The volume of a single injection is updated based on the volume correction ratio to obtain the updated volume of a single injection.

8. The DC emergency oil pump control system integrating TRT soft start and hard manual emergency intervention as described in claim 5, characterized in that, The next round of volumetric injection for the emergency oil pump is based on the updated single injection volume, including: The target volume value is updated based on the updated single injection volume to obtain the updated target volume value. The next round of volumetric injection is performed on the emergency oil pump based on the updated target volume value.

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