A method for adaptive distribution control of dual-pump confluence in a hydraulic system for a drilling rig propulsion beam.

Abstract

This invention relates to the field of drilling operation control technology, specifically to a dual-pump confluence adaptive distribution control method for a drilling rig propulsion beam hydraulic system. The invention obtains the load mutation impact coefficient at each moment based on the propulsion pressure distribution and feed rate at different times; it uses different preset PID control parameters as particles to execute a particle swarm optimization algorithm to obtain initial PID control parameters; it obtains the flow regulation amount based on the feed rate distribution at different times, the preset maximum damping coefficient, and the initial PID control parameters; it obtains the feedforward compensation amount at the current moment based on the propulsion pressure, the load mutation impact coefficient, and the preset feedforward gain coefficient; it obtains the rated flow rates of the small pump and the large pump, and combines the feedforward compensation amount and the flow regulation amount at the current moment to obtain the output flow rates of the small pump and the large pump. This invention improves the effectiveness of dual-pump confluence adaptive distribution by accurately adjusting the PID control parameters for flow distribution.

Description

Technical Field

[0001] This invention relates to the field of drilling operation control technology, specifically to a dual-pump confluence adaptive distribution control method for a drilling rig propulsion beam hydraulic system. Background Technology

[0002] Most drilling rigs generally adopt a single-pump quantitative oil supply or a fixed dual-pump oil supply mode. During the light-load no-thrust stage, the hydraulic oil redundant overflow loss is large, resulting in high overall energy consumption. During heavy-load rock drilling and propulsion, the oil supply flow is insufficient, which can easily lead to problems such as fluctuations in propulsion thrust, uneven feed rate, and increased impact vibration. This not only reduces the hole quality and construction progress, but also accelerates the wear of hydraulic valves, sealing elements and pipelines, shortening the service life of the equipment. Therefore, adaptive oil supply distribution is necessary.

[0003] In existing technologies, conventional fixed-parameter PID control is used to regulate the combined hydraulic oil supply of the drilling rig's propulsion beam by controlling the combined flow of the two pumps. The output flow of the two pumps is allocated according to a preset ratio, and the propulsion pressure and feed rate are adjusted by feedback from a fixed-gain PID controller. However, in actual operations, the rock hardness and drilling resistance change continuously and dynamically. Fixed-parameter PID controllers cannot respond quickly to sudden load changes, and the PID control parameters cannot be adaptively corrected according to the working conditions. This can easily lead to adjustment lag and overshoot oscillation, resulting in an imbalance in the combined flow ratio of the two pumps. Summary of the Invention

[0004] To address the technical problems of fixed-parameter PID controllers struggling to respond quickly to sudden load changes and the imbalance in the flow ratio of the dual-pump confluence, this invention aims to provide an adaptive distribution control method for the confluence of two pumps in the hydraulic system of a drilling rig's propulsion beam. The specific technical solution adopted is as follows:

[0005] This invention proposes a dual-pump confluence adaptive distribution control method for the hydraulic system of a drilling rig propulsion beam, the method comprising:

[0006] Obtain the propulsion pressure and feed rate of the drilling rig's propulsion hydraulic system at every moment;

[0007] Based on the propulsion pressure distribution at different times and the feed rate at each time, the load change rate and feed rate deviation rate at each time are obtained, and the load mutation influence coefficient at each time is also obtained. Different preset PID control parameters are used as particles to execute the particle swarm algorithm, and substituted into the preset transfer function prediction model. The predicted total output flow, predicted load change rate and predicted feed rate deviation rate of each particle under each iteration are output, the fitness of each particle under different iterations is obtained, and the initial PID control parameters are obtained.

[0008] Based on the differences in feed rate deviation rates between adjacent time points, the preset maximum damping coefficient, and the initial PID control parameters, the adjusted PID control parameters are obtained; based on the feed rate distribution at different time points and the adjusted PID control parameters, the flow rate regulation is obtained; based on the propulsion pressure at the current time, the load mutation influence coefficient, and the preset feedforward gain coefficient, the feedforward compensation is obtained at the current time.

[0009] Obtain the rated flow rates of the small pump and the large pump, and combine them with the feedforward compensation and flow regulation at the current moment to obtain the output flow rates of the small pump and the large pump.

[0010] Furthermore, the method for obtaining the load change rate includes:

[0011] The average propulsion pressure of all moments within a preset first time range is obtained at each moment and used as the first average pressure;

[0012] The average propulsion pressure at each moment is obtained as the second average pressure across all moments within a preset second time range.

[0013] Obtain the difference between the first average pressure and the second average pressure, and calculate the ratio of the difference to the second average pressure as the load change rate at each moment.

[0014] Furthermore, the method for obtaining the feed rate deviation rate includes:

[0015] Obtain the difference between the feed rate and the target feed rate at each moment, and calculate the ratio of the difference to the target feed rate as the feed rate deviation rate at each moment.

[0016] Furthermore, the method for obtaining the load mutation impact coefficient includes:

[0017] For each moment, the sum of the absolute values ​​of the load change rate and the feed rate deviation rate is obtained as the first sum value;

[0018] The sum of the maximum absolute value of the load change rate and the maximum absolute value of the feed rate deviation rate is obtained as the second sum; the ratio between the first sum and the second sum is obtained as the load change effect coefficient.

[0019] Furthermore, the method for obtaining the fitness includes:

[0020] The sum of the rated flow rates of the small pump and the large pump is obtained as the total rated flow rate; the ratio of the predicted total output flow rate to the total rated flow rate for each particle is obtained as the flow rate ratio.

[0021] The fitness of each particle is obtained by weighting and summing the absolute values ​​of the predicted load change rate, the predicted feed rate deviation rate, and the flow rate ratio based on preset weights.

[0022] Furthermore, the method for obtaining the initial PID control parameters includes:

[0023] The PID control parameters of the particle corresponding to the minimum fitness value after iteration are used as the initial PID control parameters.

[0024] Furthermore, the method for obtaining the adjusted PID control parameters includes:

[0025] Obtain the absolute difference in feed rate deviation rate between the current moment and the previous moment;

[0026] Obtain the sum between the absolute difference and the preset sensitivity coefficient, and calculate the ratio of the absolute difference to the sum as the damping adjustment weight;

[0027] The product between the damping adjustment weight and the preset maximum damping coefficient is obtained as the damping adjustment coefficient;

[0028] The initial PID control parameters are adjusted to reduce the gain based on the damping adjustment coefficient to obtain the adjusted PID control parameters.

[0029] Furthermore, the method for obtaining the flow rate adjustment amount includes:

[0030] The difference between the target feed rate and the feed rate at each moment is obtained as the feed rate error at each moment;

[0031] The difference between the current time and the previous time is obtained as the error rate of change;

[0032] The flow rate regulation is obtained by adjusting the PID control parameters, the feed rate error at different times, and the error change rate. The adjustment of the PID control parameters, the feed rate error, and the error change rate are all positively correlated with the flow rate regulation.

[0033] Furthermore, the method for obtaining the feedforward compensation amount includes:

[0034] The ratio between the current propulsion pressure and the preset maximum allowable propulsion pressure is obtained and used as the load level coefficient;

[0035] The product of the load mutation impact coefficient, the load level coefficient, and the preset feedforward gain coefficient is obtained as the feedforward compensation amount.

[0036] Furthermore, the method for obtaining the output flow rate of the small pump and the output flow rate of the large pump includes:

[0037] The sum of the feedforward compensation and flow regulation at the current moment is used as the total flow demand control quantity at the current moment; the sum of the rated flow of the small pump and the rated flow of the large pump is used as the total rated flow; the product of the total flow demand control quantity and the total rated flow is used as the total demand flow.

[0038] If the total demand flow rate at the current moment is less than or equal to the rated flow rate of the small pump, the total demand flow rate is used as the output flow rate of the small pump, and the output flow rate of the large pump is set to 0.

[0039] If the total demand flow rate at the current moment is greater than the rated flow rate of the small pump, the difference between the total demand flow rate and the rated flow rate of the small pump is obtained and used as the output flow rate of the large pump; the rated flow rate of the small pump is used as the output flow rate of the small pump.

[0040] The present invention has the following beneficial effects:

[0041] This invention obtains the load change rate and feed rate deviation rate at each moment based on the propulsion pressure distribution and feed rate at each moment, and obtains the load mutation impact coefficient at each moment, quantifying the comprehensive impact of geological mutation on the hydraulic system. Different preset PID control parameters are used as particles to execute the particle swarm optimization algorithm, obtaining the fitness of each particle under different iterations and obtaining the initial PID control parameters, realizing real-time adaptive matching of control parameters with dynamic geological conditions. Based on the difference characteristics of feed rate deviation rates between adjacent moments, the preset maximum damping coefficient, and the initial PID control parameters, adjusted PID control parameters are obtained, reflecting the system's adaptive capability in response to geological mutations. Based on the feed rate distribution at different moments and the adjusted PID control parameters, flow regulation is obtained, reflecting the closed-loop correction requirement for the measured feed rate deviation. Based on the propulsion pressure, load mutation impact coefficient, and preset feedforward gain coefficient at the current moment, the feedforward compensation is obtained, reflecting the predictive compensation requirement for responding to the trend of geological mutation. The rated flow rates of the small pump and the large pump are obtained, and combined with the feedforward compensation and flow regulation at the current moment, the output flow rates of the small pump and the large pump are obtained. This invention improves the effectiveness of adaptive flow distribution by accurately adjusting PID control parameters. Attached Figure Description

[0042] Figure 1 The flowchart illustrates a dual-pump confluence adaptive distribution control method for a drilling rig propulsion beam hydraulic system, as provided in one embodiment of the present invention. Detailed Implementation

[0043] The following description, in conjunction with the accompanying drawings, details the specific scheme of the dual-pump confluence adaptive distribution control method for the hydraulic system of a drilling rig propulsion beam provided by this invention.

[0044] Please see Figure 1The diagram illustrates a flowchart of a dual-pump confluence adaptive distribution control method for a drilling rig propulsion beam hydraulic system according to an embodiment of the present invention. The specific method includes:

[0045] Step S1: Obtain the propulsion pressure and feed rate of the drilling rig's propulsion hydraulic system at each moment.

[0046] In the embodiments of the present invention, under light load conditions, the flow supply is excessive, and the hydraulic overflow loss increases energy consumption; under heavy load conditions, the oil supply response is slow, and the propulsion thrust and feed rate fluctuate significantly. Therefore, in order to balance the propulsion response speed and the system operation stability, the propulsion pressure and feed rate are analyzed. First, the propulsion pressure is collected by the pressure sensor built into the drilling rig's propulsion hydraulic circuit. The sensor is installed at the inlet of the rodless chamber of the propulsion cylinder. The feed rate is obtained by the displacement encoder built into the propulsion beam. The displacement encoder is installed at the end of the propulsion beam drive rack.

[0047] It should be noted that, in the embodiments of the present invention, the sampling frequency of the propulsion pressure and the feed rate is 20 times / second, the acquisition accuracy of the propulsion pressure is ±0.05MPa, and the acquisition accuracy of the feed rate is ±0.01m / min; the data is directly connected to the drilling rig PLC system without the need for additional hardware.

[0048] It should be noted that, in the embodiments of the present invention, in order to facilitate subsequent data processing, abnormal data cleaning processing is performed on the acquired data. That is, for the propulsion pressure and feed rate, the average value and standard deviation of the most recent 10 consecutive sampling times are calculated respectively. If the deviation of the sampled data value at any time from the average value exceeds 3 times the standard deviation, the data value at the corresponding time is determined to be an abnormal value. The abnormal value is replaced with the average value of two adjacent sampling times. This effectively eliminates abnormal data caused by hydraulic system pulsation interference and poor sensor contact, and avoids load identification errors and control deviations caused by abnormal values. After cleaning the abnormal data, the maximum and minimum values ​​are normalized based on the maximum allowable propulsion pressure and the maximum calibrated value of feed rate in the benchmark design parameters. The propulsion pressure and feed rate are mapped to the [0,1] interval respectively to eliminate the influence of differences in different dimensions.

[0049] Step S2: Based on the propulsion pressure distribution at different times and the feed rate at each time, obtain the load change rate and feed rate deviation rate at each time, and obtain the load mutation influence coefficient at each time; use different preset PID control parameters as particles to execute the particle swarm algorithm, substitute them into the preset transfer function prediction model, obtain the predicted total output flow, predicted load change rate and predicted feed rate deviation rate of each particle in each iteration, obtain the fitness of each particle in different iterations, and obtain the initial PID control parameters.

[0050] The propulsion pressure reflects the magnitude of the drilling load. Higher propulsion pressure indicates higher formation hardness and a heavier load. Therefore, the load change rate at each moment can be obtained based on the propulsion pressure distribution at different times.

[0051] Preferably, considering the high-frequency pulsating noise in the hydraulic propulsion system and the strong vibrations accompanying drilling operations, directly using single-point instantaneous sampling values ​​to calculate pressure changes would result in an extremely low signal-to-noise ratio and lead to misjudgments; in one embodiment of the present invention, the method for obtaining the load change rate includes:

[0052] The average propulsion pressure of all moments within a preset first time range is obtained at each moment and used as the first average pressure;

[0053] The average propulsion pressure at each moment is obtained as the second average pressure across all moments within a preset second time range.

[0054] Obtain the difference between the first average pressure and the second average pressure, and calculate the ratio of the difference to the second average pressure as the load change rate at each moment.

[0055] It should be noted that when the equipment is first started and the drill bit is suspended in the air and not touching the rock layer for unloaded propulsion, the propulsion pressure may be 0. Therefore, when calculating the ratio, a very small positive number with the same dimensions is added to the denominator. The value of this number is set according to the range of values ​​of the denominator, which will not be elaborated here.

[0056] It should be noted that, in one embodiment of the present invention, the preset first time range is a range of 1 second in duration, based on each moment and its historical moments; the preset second time range is a range of 5 seconds in duration, based on each moment and its historical moments; in other embodiments of the present invention, the size of the preset first time range and the preset second time range can be specifically set according to the specific situation, and will not be limited or elaborated here.

[0057] Based on this, the first average pressure represents the instantaneous value at a single point, while the second average pressure reflects the recent baseline state. This is intended to filter out high-frequency hydraulic pulsation interference and make the rate of change more accurately reflect the actual abrupt changes in formation load. A positive difference indicates that the first average pressure is greater than the second average pressure, meaning that the advance pressure is gradually increasing, and it is more likely to enter a hard formation, resulting in a larger load and a greater rate of change in load. A negative difference indicates that the first average pressure is less than the second average pressure, meaning that the advance pressure is gradually decreasing, and it is more likely to enter a soft formation or fractured zone, resulting in a smaller load and a smaller rate of change in load.

[0058] Feed rate reflects the degree of matching between flow supply and load demand. Under the same propulsion pressure, the lower the feed rate, the less flow supply there is, and the higher the feed rate, the more flow supply there is. Therefore, based on the feed rate at each moment, the feed rate deviation rate at each moment can be obtained to quantify the degree of deviation of flow supply.

[0059] Preferably, in one embodiment of the present invention, the method for obtaining the feed rate deviation rate is as follows:

[0060] Obtain the difference between the feed rate and the target feed rate at each moment, and calculate the ratio of the difference to the target feed rate as the feed rate deviation rate at each moment.

[0061] It should be noted that the target feed rate is a pre-set process value obtained from the drilling process design documents before drilling begins, and is greater than 0. The greater the difference between the feed rate and the target feed rate, the greater the feed rate, the more excessive the flow supply, and the greater the feed rate deviation rate.

[0062] Preferably, in an embodiment of the present invention, the method for obtaining the load mutation influence coefficient includes:

[0063] For each moment, the sum of the absolute values ​​of the load change rate and the feed rate deviation rate is obtained as the first sum value;

[0064] The sum of the maximum absolute value of the load change rate and the maximum absolute value of the feed rate deviation rate is obtained as the second sum; the ratio between the first sum and the second sum is obtained as the load change effect coefficient.

[0065] It should be noted that the maximum absolute value of the load change rate is an empirical value of the upper limit of the load change rate range, which is manually preset based on the historical operating statistics of the equipment; the maximum absolute value of the feed rate deviation rate is an empirical value of the upper limit of the feed rate deviation rate range, which is manually preset based on the historical operating statistics of the equipment.

[0066] Based on this, the larger the absolute value of the load change rate, the greater the change in propulsion pressure, the more drastic the load change, and the higher the probability of formation change; the larger the absolute value of the feed rate deviation rate, the more mismatched the flow supply and load demand, and the higher the probability of formation change. Therefore, the closer the first sum is to the second sum, the greater the load change influence coefficient; the smaller the first sum, the more stable the propulsion pressure, the smaller the feed rate deviation rate, the more stable the load, and the smaller the load change influence coefficient.

[0067] Different preset PID control parameters are used as particles to execute the particle swarm algorithm. They are substituted into the preset transfer function prediction model to output the predicted total output flow, predicted load change rate, and predicted feed speed deviation rate of each particle in each iteration.

[0068] It should be noted that traditional PID control parameters are mostly fixed values ​​tuned manually, only suitable for a specific working condition, and cannot be dynamically adjusted when faced with sudden load changes. Therefore, a particle swarm optimization algorithm is used for online optimization. The search dimension of the particle swarm optimization algorithm is set to 3, corresponding to the three PID control parameters to be optimized: proportional coefficient, integral coefficient, and derivative coefficient. The initial particle swarm size is 20, and each particle corresponds to a set of randomly generated PID control parameters within a pre-calibrated positive real number constraint boundary. The number of iterations is set to 10, and the single optimization operation time is less than 50ms, which fully meets the real-time control requirement of 20 times / second. It should be noted that the positive real number constraint boundary is obtained based on the pre-drilling load calibration test data when the drilling rig leaves the factory, ensuring that the control parameters within the search range will not cause the transfer function prediction model to enter an unstable state of divergence and oscillation.

[0069] It should be noted that the preset transfer function prediction model is a second-order transfer function equation constructed based on the drilling rig's hydraulic propulsion unit, containing flow-velocity and flow-pressure transfer functions with identical structures. Its specific expression is as follows: ;in, Indicates the gain of the hydraulic system. Indicates the system's natural frequency. The system damping ratio is represented by the flow-velocity transfer function and the flow-pressure transfer function, respectively, which correspond to independent model parameters. , and Pre-calibration is performed based on the equipment system identification data before drilling begins.

[0070] Within each control cycle, the deviation of the feed rate from the target feed rate at the current moment and historical moments is combined, and the PID control parameters corresponding to each particle are substituted into the discrete PID positional algorithm for offline calculation to obtain the total demand flow rate as the predicted total output flow rate. The total output flow rate is then substituted into the transfer function prediction model for offline simulation and deduction to output the predicted feed rate and predicted propulsion pressure at the next moment. Then, based on the above-mentioned methods for obtaining the load change rate and feed rate deviation rate, the predicted load change rate and predicted feed rate deviation rate of each particle are obtained, thereby obtaining the fitness of each particle under different iterations.

[0071] Preferably, in one embodiment of the present invention, the method for obtaining fitness includes:

[0072] The sum of the rated flow rates of the small pump and the large pump is obtained as the total rated flow rate; the ratio of the predicted total output flow rate to the total rated flow rate for each particle is obtained as the flow rate ratio.

[0073] The fitness of each particle is obtained by weighting and summing the absolute values ​​of the predicted load change rate, the predicted feed rate deviation rate, and the flow rate ratio based on preset weights.

[0074] It should be noted that, in the embodiments of the present invention, considering that the feed rate is directly related to the construction progress and hole-forming efficiency, it is the dominant optimization direction; drastic fluctuations in the propulsion pressure can easily cause the drill to jam, so for equipment safety, a weighted forced optimization algorithm is needed to balance control stability and play a constraining role; while the flow rate ratio reflects energy consumption and plays an auxiliary optimization role; therefore, the preset weight of the absolute value of the feed rate deviation rate is greater than the preset weight of the absolute value of the load change rate, the preset weight of the absolute value of the load change rate is greater than the preset weight of the flow rate ratio, and the sum of the preset weights is 1, which are set to 0.5, 0.3, and 0.2 in sequence according to relevant historical experience; in other embodiments of the present invention, the size of the preset weights can be set according to specific circumstances, which are not limited or elaborated here.

[0075] Preferably, in one embodiment of the present invention, the method for obtaining the initial PID control parameters includes:

[0076] The PID control parameters of the particle corresponding to the minimum fitness value after iteration are used as the initial PID control parameters.

[0077] It should be noted that the smaller the fitness value, the better the control effect of the PID parameters, and the more suitable they are as initial PID control parameters, reflecting the initial set values ​​of the PID controller parameters before the actual system is put into operation.

[0078] Step S3: Based on the difference characteristics of the feed rate deviation rate between adjacent time moments, the preset maximum damping coefficient, and the initial PID control parameters, obtain the adjusted PID control parameters; based on the feed rate distribution at different time moments and the adjusted PID control parameters, obtain the flow rate regulation amount; based on the propulsion pressure at the current time, the load change influence coefficient, and the preset feedforward gain coefficient, obtain the feedforward compensation amount at the current time.

[0079] The feed rate deviation rate reflects the degree of matching between the flow supply of the hydraulic system and the actual load demand of the formation. The difference in the feed rate deviation rate between adjacent moments reflects the rate and severity of change of the feed rate deviation. The smaller the difference, the more stable the system tends to be, and the smaller the adjustment of the PID control parameters. Based on the difference in the feed rate deviation rate between adjacent moments, the preset maximum damping coefficient, and the initial PID control parameters, the PID control parameters are adjusted.

[0080] Preferably, in one embodiment of the present invention, the method for obtaining the PID control parameters includes:

[0081] Obtain the absolute difference in feed rate deviation rate between the current moment and the previous moment;

[0082] Obtain the sum between the absolute difference and the preset sensitivity coefficient, and calculate the ratio of the absolute difference to the sum as the damping adjustment weight;

[0083] It should be noted that the absolute difference represents the absolute value of the difference. In one embodiment of the present invention, in order to prevent the calculation from being meaningless when the absolute difference is 0, and to ensure the sensitivity of the smoothing damping coefficient to changes in very small deviations, the preset sensitivity coefficient is set to 0.05 based on relevant historical experience. In other embodiments of the present invention, the value of the preset sensitivity coefficient can be set according to specific circumstances, and will not be limited or elaborated here.

[0084] The product between the damping adjustment weight and the preset maximum damping coefficient is obtained as the damping adjustment coefficient; the initial PID control parameters are adjusted to reduce the gain based on the damping adjustment coefficient to obtain the adjusted PID control parameters.

[0085] It should be noted that, in one embodiment of the present invention, the damping coefficient is used to counteract the overly aggressive parameters found by the particle swarm optimization algorithm due to drastic load changes, and to prevent the hydraulic valve from abruptly actuating and causing oil circuit shock or overshoot oscillation. However, in order to prevent the system from reacting slowly and being unable to overcome the sudden resistance due to excessive damping, the maximum damping coefficient is preset to 0.3 based on relevant historical experience. In other embodiments of the present invention, the size of the preset maximum damping coefficient can be set according to specific circumstances, and will not be limited or elaborated here.

[0086] It should be noted that the role of damping is to offset part of the adjustment range and avoid overshoot oscillation caused by excessive adjustment. Therefore, it is necessary to adjust the initial PID control parameters to reduce the loss. The larger the absolute difference, the greater the difference in feed rate deviation rate between the current time and the previous time, the greater the fluctuation, the greater the damping adjustment weight, the greater the offsetting range, and the greater the degree of loss adjustment to the initial PID control parameters. The smaller the absolute difference, the smaller the difference in feed rate deviation rate between the current time and the previous time, the smaller the fluctuation, the smaller the damping adjustment weight, the smaller the offsetting range, and the smaller the degree of loss adjustment to the initial PID control parameters. In one embodiment of the present invention, the difference between the constant 1 and the damping adjustment coefficient is obtained, and the product between the difference and the initial PID control parameters is calculated as the adjusted PID control parameters.

[0087] Feed rate reflects the degree of matching between flow supply and load demand, and helps to quantify feed rate deviation and analyze flow supply. Adjusting PID control parameters reflects the system's adaptive ability to cope with geological changes. Based on the feed rate distribution at different times and by adjusting PID control parameters, the flow regulation amount can be obtained.

[0088] Preferably, in one embodiment of the present invention, the method for obtaining the flow rate adjustment amount includes:

[0089] The difference between the target feed rate and the feed rate at each moment is obtained as the feed rate error at each moment;

[0090] The difference between the current time and the previous time is obtained as the error rate of change;

[0091] The flow rate regulation is obtained by adjusting the PID control parameters, the feed rate error at different times, and the error change rate. The adjustment of the PID control parameters, the feed rate error, and the error change rate are all positively correlated with the flow rate regulation.

[0092] It should be noted that the larger the feed rate error, the larger the feed rate at the current moment, and the more the flow rate needs to be increased; the larger the error change rate, the larger the feed rate deviation at the current moment, and the more the flow rate needs to be increased; therefore, adjusting the PID control parameters, feed rate error, and error change rate are all positively correlated with the flow rate adjustment.

[0093] In one embodiment of the present invention, a first product is obtained between the proportional coefficient in the adjusted PID control parameters and the feed rate error at the current moment; a second product is obtained between the integral coefficient in the adjusted PID control parameters and the cumulative feed rate error at all times; a third product is obtained between the derivative coefficient in the adjusted PID control parameters and the error change rate corresponding to the current moment; and the sum of the first, second, and third products is obtained as the flow rate adjustment amount.

[0094] The formula for flow regulation is expressed as:

[0095] ;in, Indicates the amount of flow regulation; This indicates adjusting the proportional coefficient in the PID control parameters; Indicates the current time The feed rate error; This indicates adjusting the integral coefficient in the PID control parameters; This indicates the quantity up to the current time. This indicates adjusting the derivative coefficients in the PID control parameters; Indicates the previous moment The feed rate error.

[0096] The propulsion pressure reflects the drilling load, and the load mutation impact coefficient quantifies the comprehensive impact of geological mutations on the hydraulic system. The greater the propulsion pressure, the greater the load mutation impact coefficient, the heavier the load, and the greater the flow rate required by the dual pumps converging. The feedforward compensation amount at the current moment is obtained based on the propulsion pressure, the load mutation impact coefficient, and the preset feedforward gain coefficient.

[0097] Preferably, in an embodiment of the present invention, the method for obtaining the feedforward compensation amount includes:

[0098] The ratio between the current propulsion pressure and the preset maximum allowable propulsion pressure is obtained and used as the load level coefficient;

[0099] The product of the load mutation impact coefficient, the load level coefficient, and the preset feedforward gain coefficient is obtained as the feedforward compensation amount.

[0100] It should be noted that the load level coefficient reflects the severity of the load. The higher the propulsion pressure relative to the preset maximum allowable propulsion pressure, the higher the load level, and the greater the need for feedforward compensation. The higher the load change influence coefficient, the more severe the impact of load change on the working condition, and the greater the need for feedforward compensation to improve the response speed. In one embodiment of the present invention, the preset maximum allowable propulsion pressure is obtained in advance from the drilling process design document before drilling begins, and the preset feedforward gain coefficient is set to 0.2. In other embodiments of the present invention, the size of the preset feedforward gain coefficient can be set according to specific circumstances, and will not be limited or elaborated here.

[0101] Step S4: Obtain the rated flow rate of the small pump and the rated flow rate of the large pump. Combine the feedforward compensation and flow regulation at the current moment to obtain the output flow rate of the small pump and the output flow rate of the large pump.

[0102] The feedforward compensation reflects the anticipated compensation requirements for responding to sudden changes in formation trends. The larger the feedforward compensation, the greater the total flow supply; the smaller the feedforward compensation, the smaller the total flow supply. The flow regulation reflects the closed-loop correction requirement for the measured deviation of the feed rate. Considering that the mainstream drilling rig propulsion hydraulic system adopts a small-flow fixed-displacement pump + large-flow variable pump architecture, the rated flow of the small pump reflects the baseline oil supply capacity of the drilling rig during the light-load stage; the rated flow of the large pump reflects the ultimate supplementary oil supply capacity of the drilling rig during the heavy-load stage. Therefore, by obtaining the rated flow of the small pump and the rated flow of the large pump, and combining the feedforward compensation and flow regulation at the current moment, the output flow of the small pump and the output flow of the large pump can be obtained.

[0103] Preferably, in one embodiment of the present invention, the method for obtaining the output flow rate of the small pump and the output flow rate of the large pump includes:

[0104] The sum of the feedforward compensation and flow regulation at the current moment is used as the total flow demand control quantity at the current moment; the sum of the rated flow of the small pump and the rated flow of the large pump is used as the total rated flow; the product of the total flow demand control quantity and the total rated flow is used as the total demand flow.

[0105] If the total demand flow rate at the current moment is less than or equal to the rated flow rate of the small pump, the total demand flow rate is used as the output flow rate of the small pump, and the output flow rate of the large pump is set to 0.

[0106] If the total demand flow rate at the current moment is greater than the rated flow rate of the small pump, the difference between the total demand flow rate and the rated flow rate of the small pump is obtained and used as the output flow rate of the large pump; the rated flow rate of the small pump is used as the output flow rate of the small pump.

[0107] It should be noted that the rated flow rates of the small pump and the large pump are obtained in advance from the drilling process design documents before drilling begins; if the total required flow rate is less than the rated flow rate of the small pump, only the small pump is started to supply oil, and the large pump does not work; if the total required flow rate is greater than the rated flow rate of the small pump, the small pump outputs at full load, and the large pump supplements the remaining flow rate.

[0108] Based on this, the output flow control signals of the large and small pumps are output to the hydraulic proportional valve, and the swashplate angle and unloading valve status of the large pump are adjusted so that the output flow of the two pumps reaches the target value, adapting to different drilling load conditions. This achieves adaptive control of the dual-pump confluence without the need for additional hardware.

[0109] In summary, this invention obtains the load mutation impact coefficient at each moment based on the propulsion pressure distribution and feed rate at different times; it obtains initial PID control parameters by using different preset PID control parameters as particles in the particle swarm optimization algorithm; it obtains the flow regulation amount based on the feed rate distribution at different times, the preset maximum damping coefficient, and the initial PID control parameters; it obtains the feedforward compensation amount at the current moment based on the propulsion pressure, load mutation impact coefficient, and preset feedforward gain coefficient; and it obtains the rated flow rates of the small pump and the large pump, and combines the feedforward compensation amount and the flow regulation amount at the current moment to obtain the output flow rates of the small pump and the large pump. This invention improves the effectiveness of adaptive flow distribution during dual-pump confluence by accurately adjusting the PID control parameters for flow allocation.

[0110] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for adaptive distribution control of a dual pump combined flow of a hydraulic system of a drilling rig push beam, characterized in that, The method includes: Obtain the propulsion pressure and feed rate of the drilling rig's propulsion hydraulic system at every moment; Based on the propulsion pressure distribution at different times and the feed rate at each time, the load change rate and feed rate deviation rate at each time are obtained, and the load mutation influence coefficient at each time is also obtained. Different preset PID control parameters are used as particles to execute the particle swarm algorithm, and substituted into the preset transfer function prediction model. The predicted total output flow, predicted load change rate and predicted feed rate deviation rate of each particle under each iteration are output, the fitness of each particle under different iterations is obtained, and the initial PID control parameters are obtained. Based on the differences in feed rate deviation rates between adjacent time points, the preset maximum damping coefficient, and the initial PID control parameters, the adjusted PID control parameters are obtained; based on the feed rate distribution at different time points and the adjusted PID control parameters, the flow rate regulation is obtained; based on the propulsion pressure at the current time, the load mutation influence coefficient, and the preset feedforward gain coefficient, the feedforward compensation is obtained at the current time. Obtain the rated flow rates of the small pump and the large pump, and combine them with the feedforward compensation and flow regulation at the current moment to obtain the output flow rates of the small pump and the large pump.

2. The double pump confluence adaptive distribution control method of a drilling rig push beam hydraulic system according to claim 1, characterized in that, The method for obtaining the load change rate includes: Obtain the average propulsion pressure of all times within a preset first time range at each moment, and use it as the first average pressure; The average propulsion pressure at each moment is obtained as the second average pressure across all moments within a preset second time range. Obtain the difference between the first average pressure and the second average pressure, and calculate the ratio of the difference to the second average pressure as the load change rate at each moment.

3. The adaptive distribution control method for dual-pump confluence in a drilling rig propulsion beam hydraulic system according to claim 1, characterized in that, The method for obtaining the feed rate deviation rate includes: Obtain the difference between the feed rate and the target feed rate at each moment, and calculate the ratio of the difference to the target feed rate as the feed rate deviation rate at each moment.

4. The adaptive distribution control method for dual-pump confluence in a drilling rig propulsion beam hydraulic system according to claim 1, characterized in that, The method for obtaining the load mutation impact coefficient includes: For each moment, the sum of the absolute values ​​of the load change rate and the feed rate deviation rate is obtained as the first sum value; The sum of the maximum absolute value of the load change rate and the maximum absolute value of the feed rate deviation rate is obtained as the second sum; the ratio between the first sum and the second sum is obtained as the load change effect coefficient.

5. The adaptive distribution control method for dual-pump confluence in a drilling rig propulsion beam hydraulic system according to claim 1, characterized in that, The method for obtaining fitness includes: The sum of the rated flow rates of the small pump and the large pump is obtained as the total rated flow rate; the ratio of the predicted total output flow rate to the total rated flow rate for each particle is obtained as the flow rate ratio. The fitness of each particle is obtained by weighting and summing the absolute values ​​of the predicted load change rate, the predicted feed rate deviation rate, and the flow rate ratio based on preset weights.

6. The adaptive distribution control method for dual-pump confluence in a hydraulic system for a drilling rig propulsion beam according to claim 1, characterized in that, The method for obtaining the initial PID control parameters includes: The PID control parameters of the particle corresponding to the minimum fitness value after iteration are used as the initial PID control parameters.

7. The adaptive distribution control method for dual-pump confluence in a hydraulic system for a drilling rig propulsion beam according to claim 1, characterized in that, The method for obtaining the adjusted PID control parameters includes: Obtain the absolute difference in feed rate deviation rate between the current moment and the previous moment; Obtain the sum between the absolute difference and the preset sensitivity coefficient, and calculate the ratio of the absolute difference to the sum as the damping adjustment weight; The product between the damping adjustment weight and the preset maximum damping coefficient is obtained as the damping adjustment coefficient; The initial PID control parameters are adjusted to reduce the gain based on the damping adjustment coefficient to obtain the adjusted PID control parameters.

8. The adaptive distribution control method for dual-pump confluence in a hydraulic system for a drilling rig propulsion beam according to claim 1, characterized in that, The method for obtaining the flow regulation amount includes: The difference between the target feed rate and the feed rate at each moment is obtained as the feed rate error at each moment; The difference between the current time and the previous time is obtained as the error rate of change; The flow rate regulation is obtained by adjusting the PID control parameters, the feed rate error at different times, and the rate of change of the deviation. The adjustment of the PID control parameters, the feed rate error, and the rate of change of the error are all positively correlated with the flow rate regulation.

9. The adaptive distribution control method for dual-pump confluence in a hydraulic system for a drilling rig propulsion beam according to claim 1, characterized in that, The method for obtaining the feedforward compensation amount includes: The ratio between the current propulsion pressure and the preset maximum allowable propulsion pressure is obtained and used as the load level coefficient; The product of the load mutation impact coefficient, the load level coefficient, and the preset feedforward gain coefficient is obtained as the feedforward compensation amount.

10. The adaptive distribution control method for dual-pump confluence in a hydraulic system for a drilling rig propulsion beam according to claim 1, characterized in that, The methods for obtaining the output flow rate of the small pump and the output flow rate of the large pump include: The sum of the feedforward compensation and flow regulation at the current moment is used as the total flow demand control quantity at the current moment; the sum of the rated flow of the small pump and the rated flow of the large pump is used as the total rated flow; the product of the total flow demand control quantity and the total rated flow is used as the total demand flow. If the total demand flow rate at the current moment is less than or equal to the rated flow rate of the small pump, the total demand flow rate is used as the output flow rate of the small pump, and the output flow rate of the large pump is set to 0. If the total demand flow rate at the current moment is greater than the rated flow rate of the small pump, the difference between the total demand flow rate and the rated flow rate of the small pump is obtained and used as the output flow rate of the large pump; the rated flow rate of the small pump is used as the output flow rate of the small pump.

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