Stepless gas volume regulation method, device, equipment and medium for reciprocating compressor

Abstract

The application provides a kind of stepless air volume regulation method, device, equipment and medium of reciprocating compressor, belongs to compressor control technical field.The method includes: the crankshaft speed and each cylinder reference backflow duration are collected, with the moment when crankshaft passes through reference phase angle as starting point, current phase is calculated in combination with speed and duration, then the absolute phase angle of each crank is obtained according to preset phase difference;Introduce pipeline pulsation compensation phase angle and damping coefficient, calculate the phase compensation duration of each cylinder in combination with speed, to correct the suction pulsation phase difference caused by the difference of intake pipeline;Actual backflow duration is obtained by subtracting the compensation duration from reference backflow duration;When the absolute phase angle of any crank reaches the intake termination phase angle, control corresponding intake valve to open backflow, and close after maintaining the actual backflow duration.The application can avoid that suction pulsation superposition caused by detection error and pipeline phase deviation cannot be effectively eliminated, so as to accurately guarantee the stability of compressor gas supply.

Description

Technical Field

[0001] This invention relates to the field of compressor control technology, specifically to a stepless air volume regulation method for a reciprocating compressor, a stepless air volume regulation device for a reciprocating compressor, an electronic device, and a computer-readable storage medium. Background Technology

[0002] In industrial applications of reciprocating compressors, especially in supplying syngas to upstream equipment, it is necessary to regulate the compressor's gas flow rate according to changes in process load to achieve energy saving and stable gas supply. Traditional gas flow rate regulation methods, such as bypass regulation and clearance regulation, suffer from problems such as significant energy waste and discontinuous regulation. Therefore, stepless gas flow rate regulation technology based on partial stroke pressure-opening of the intake valve has gradually been applied, which can continuously regulate the compressor's gas delivery rate and significantly reduce energy consumption. However, for multi-cylinder reciprocating compressors that use multiple cranks arranged at staggered angles on the same crankshaft to drive multiple compression components, each compression component receives gas intermittently at a certain phase, resulting in strong pressure pulsations in the airflow within the intake pipeline. Especially under partial load conditions, the pulsation waves generated by the intake and shut-off processes of different compression components superimpose in the shared or connected intake pipeline, causing a severe pulsation superposition effect and affecting the stability of the compressor's gas supply.

[0003] Currently, a continuously variable air volume (CVV) regulation system based on crankshaft phase detection, such as the HydroCOM CVV system, is employed. This system utilizes a crankshaft position sensor to determine the rhythm and position of crankshaft operation. The controller calculates the duration for which the intake valve needs to remain open for gas recirculation for each compression component based on the required load. When a compression component is detected to have reached a preset intake termination angle, the controller issues a command to forcefully open the intake valve of that component via an actuator, allowing gas to begin recirculation. After the calculated recirculation time, the intake valve closes, ensuring that the compression component completes only a portion of its effective stroke, ultimately achieving continuous regulation of the overall compressor's air delivery volume. This control method attempts to ensure the stability of the compressor's air supply by precisely controlling the closing time of each intake valve.

[0004] However, because existing technology does not take into account the phase deviation caused by pipeline differences and cannot eliminate the timing accumulation error in the crankshaft phase detection process, it cannot accurately guarantee the stability of the compressor's air supply. Summary of the Invention

[0005] The purpose of this invention is to provide a method, apparatus, equipment, and medium for stepless gas volume adjustment of a reciprocating compressor to solve the above-mentioned problems.

[0006] To achieve the above objectives, embodiments of the present invention provide a stepless air volume adjustment method for a reciprocating compressor. The reciprocating compressor includes multiple compression components and a crankshaft assembly. The crankshaft assembly includes multiple cranks disposed on the same crankshaft, with each crank offset from the others by a preset angle. Each crank is connected to a corresponding compression component, including: Collect crankshaft rotation speed and reference gas reflux time for each compression component; The starting time is determined by identifying the moment when the crankshaft last rotated to the reference phase angle, and the current time is determined by identifying the moment when the crankshaft phase angle needs to be acquired. The current phase angle of the crankshaft is determined by multiplying the elapsed time from the starting time to the current time by the crankshaft rotation speed. Based on the current phase angle of the crankshaft and the preset phase difference between each crank and the reference phase angle of the crankshaft, the current absolute phase angle of each crank is obtained. Based on the crankshaft speed, the preset pipeline intake pulsation compensation phase angle of each crank, and the preset damping correction coefficient, the phase compensation time of each crank is obtained; among which, the preset pipeline intake pulsation compensation phase angle is used to characterize the phase difference of intake pulsation propagation caused by the difference in the intake pipeline system corresponding to the compression assembly. The difference between the reference gas recirculation time of each compression component and the phase compensation time of each crank is calculated to obtain the actual gas recirculation time of each compression component. When the current absolute phase angle of any crank reaches the intake termination phase angle corresponding to that crank, the compressor component corresponding to that crank is controlled to start gas recirculation, and after waiting for the actual gas recirculation time of the compressor component corresponding to that crank, the compressor component corresponding to that crank is controlled to stop gas recirculation.

[0007] Optionally, based on the crankshaft speed, the preset pipeline intake pulsation compensation phase angle for each crank, and the preset damping correction coefficient, the phase compensation duration for each crank is obtained, including: For each bend: The following formula is used to calculate the crankshaft speed, the preset pipeline intake pulsation compensation phase angle of the current crank, and the preset damping correction coefficient to obtain the phase compensation duration of the current crank. ;in, This indicates the phase compensation duration of the current crank. Indicates the crankshaft rotational speed. This indicates the preset pipeline intake pulsation compensation phase angle for the current crankshaft. This indicates the preset damping correction coefficient.

[0008] Optionally, the preset damping correction factor is corrected in the following way: Collect the pulsation signal of the intake manifold and the number of compression components; Spectral analysis was performed on the pulsating signal of the intake manifold to obtain the dominant frequency and amplitude of the pulsating signal. The fundamental frequency of airflow pulsation is obtained by calculating the crankshaft speed and the number of compression components using the following formula; ;in, The fundamental frequency representing airflow pulsation. Indicates the crankshaft rotational speed. Indicates the number of compression components; If the absolute value of the difference between the dominant frequency of the intake manifold pulsation signal and the fundamental frequency of the airflow pulsation is less than the preset frequency, and the amplitude of the intake manifold pulsation signal is greater than the preset amplitude, then the preset damping correction coefficient is increased; or If the absolute value of the difference between the main frequency of the pulsation signal in the intake pipe and the fundamental frequency of the airflow pulsation is less than the preset frequency, and the amplitude of the pulsation signal in the intake pipe is less than the preset amplitude, then the preset damping correction coefficient is reduced.

[0009] Optionally, the preset pipeline intake pulsation compensation phase angle for each crank is determined in the following way: For each bend: Obtain the airflow pulsation propagation speed at the intake confluence area and the equivalent length of the pipeline from the intake port of the compression component corresponding to the current crank to the intake confluence area; Calculate the ratio of the equivalent pipe length corresponding to the current crank to the airflow pulsation propagation speed at the intake confluence region to obtain the pulsation propagation delay time of the current crank. The preset pipeline intake pulsation compensation phase angle of the current crankshaft is obtained by multiplying the current crankshaft rotational speed by the pulsation propagation delay time of the current crankshaft.

[0010] Optionally, before the step where the current absolute phase angle of any crank reaches the intake termination phase angle corresponding to that crank, the stepless air volume adjustment method for the reciprocating compressor further includes: Collect the exhaust pressure of each compression component; For each compression component: If the current exhaust pressure of the compression assembly is less than the corresponding preset target pressure, then reduce the actual gas recirculation time of the current compression assembly; or If the exhaust pressure of the current compression component is greater than the corresponding preset target pressure, then the actual gas recirculation time of the current compression component is increased.

[0011] Optionally, the stepless air volume regulation method for the reciprocating compressor also includes: Collect and control the hydraulic oil pressure of the hydraulic oil circuit that controls the gas return of each compression component; When the hydraulic oil pressure in the hydraulic circuit controlling the gas return of any compression component is less than the preset pressure, the air inlet and outlet of that compression component are connected.

[0012] In a second aspect of the present invention, a stepless air volume regulating device for a reciprocating compressor is provided. The reciprocating compressor includes multiple compression components and a crankshaft assembly. The crankshaft assembly includes multiple cranks disposed on the same crankshaft, and the cranks are staggered from each other by a preset angle. Each crank is connected to a corresponding compression component, including: The parameter acquisition module is used to acquire the crankshaft speed and the reference gas reflux time of each compression component; The phase calculation module is used to determine the moment when the crankshaft last rotated to the reference phase angle as the starting moment, and to determine the moment when the phase angle of the crankshaft needs to be obtained as the current moment; and to calculate the product of the time elapsed from the starting moment to the current moment and the crankshaft speed to determine the current phase angle of the crankshaft. The phase calibration module is used to obtain the current absolute phase angle of each crank based on the current phase angle of the crankshaft and the preset phase difference between each crank and the reference phase angle of each crank relative to the crankshaft. The compensation calculation module is used to obtain the phase compensation duration of each crank based on the crankshaft speed, the preset pipeline intake pulsation compensation phase angle of each crank, and the preset damping correction coefficient; wherein, the preset pipeline intake pulsation compensation phase angle is used to characterize the phase difference of intake pulsation propagation caused by the difference in the intake pipeline system corresponding to the compression assembly. The duration correction module is used to calculate the difference between the reference gas recirculation time of each compression component and the phase compensation time of each crank, so as to obtain the actual gas recirculation time of each compression component. The recirculation control module is used to control the compression component corresponding to any crank to start gas recirculation when the current absolute phase angle of any crank reaches the intake termination phase angle corresponding to that crank, and to control the compression component corresponding to the crank to stop gas recirculation after waiting for the actual gas recirculation time of the compression component corresponding to that crank.

[0013] Optionally, the compensation calculation module is specifically used for: For each bend: The following formula is used to calculate the crankshaft speed, the preset pipeline intake pulsation compensation phase angle of the current crank, and the preset damping correction coefficient to obtain the phase compensation duration of the current crank. ;in, This indicates the phase compensation duration of the current crank. Indicates the crankshaft rotational speed. This indicates the preset pipeline intake pulsation compensation phase angle for the current crankshaft. This indicates the preset damping correction coefficient.

[0014] In a third aspect of the present invention, an electronic device is provided, comprising: a processor and a memory, the memory storing machine-readable instructions executable by the processor, wherein the machine-readable instructions, when executed by the processor, perform the stepless air volume regulation method of the reciprocating compressor described above.

[0015] In a fourth aspect of the present invention, a computer-readable storage medium is provided, storing computer instructions that, when executed on a computer, cause the computer to perform the above-described stepless air volume regulation method for a reciprocating compressor.

[0016] In this embodiment of the invention, the current phase angle is recalculated by taking the moment when the crankshaft last rotated to the reference phase angle as the starting point, which completely eliminates the accumulated error caused by traditional continuous timing. At the same time, a preset pipeline intake pulsation compensation phase angle and a preset damping correction coefficient are introduced for each crank, which accurately compensates for the intake pulsation propagation phase difference caused by the difference in the intake pipeline system. This avoids the inability to effectively eliminate the superposition of intake pulsations caused by detection errors and pipeline phase deviations, thereby accurately ensuring the stability of the compressor's air supply.

[0017] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0018] The accompanying drawings are provided to further illustrate embodiments of the present invention and form part of the specification. They are used together with the following detailed description to explain the embodiments of the present invention, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic flowchart of the stepless air volume adjustment method for a reciprocating compressor provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the reciprocating compressor provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the stepless air volume adjustment device for a reciprocating compressor provided in an embodiment of the present invention. Detailed Implementation

[0019] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of the present invention.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this application.

[0021] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0022] Example 1 like Figure 1 As shown, Figure 1 This is a flowchart illustrating the stepless air volume adjustment method for a reciprocating compressor provided in an embodiment of the present invention. The reciprocating compressor includes multiple compression components and a crankshaft assembly. The crankshaft assembly includes multiple cranks disposed on the same crankshaft, and the cranks are staggered from each other by a preset angle. Each crank is connected to a corresponding compression component. The method includes the following steps: S100 collects the crankshaft speed and the reference gas reflux time of each compression component; Specifically, such as Figure 2 As shown, the multiple compression components include: a first compression unit, a second compression unit, and a third compression unit; the first compression unit includes three rows of cylinder units, the second compression unit includes two rows of cylinder units, and the third compression unit includes one row of cylinder units; the three rows of cylinder units of the first compression unit are located on the same side, the two rows of cylinder units of the second compression unit and the one row of cylinder units of the third compression unit are located on the same side, each crank is connected to each row of cylinder units, and the offset angle between adjacent rows of cranks on the same side is 120 degrees, and the offset angle between opposing rows of cranks is 180 degrees, each crank is connected to the corresponding cylinder unit.

[0023] It should be noted that the embodiments of the present invention are implemented based on the HydroCOM stepless air volume regulation system. Specifically, the input end of each compression component is connected to the output end of the upstream equipment via an intake pipeline, and each intake valve is installed on the corresponding intake pipeline; the HydroCOM stepless air volume regulation system includes: a hydraulic station, multiple mechanical actuators, a PLC control system, a speed sensor, a dead center sensor, and multiple first solenoid valves; the oil outlet of the hydraulic station is connected to the oil inlet of each mechanical actuator via a hydraulic pipeline, each first solenoid valve is installed on the corresponding hydraulic pipeline, the speed sensor is installed on the crankshaft, the dead center sensor is installed at the reference phase angle position of the crankshaft, and the PLC control system is electrically connected to the speed sensor, the dead center sensor, and the multiple first solenoid valves respectively.

[0024] The hydraulic power unit includes an oil tank, a hydraulic pump, a relief valve, an accumulator, and a filter. The hydraulic pump is driven by an electric motor, which draws hydraulic oil from the oil tank and pressurizes it to a set pressure (e.g., 10-20 MPa). The high-pressure oil is then supplied to each hydraulic pipeline after being stabilized by the accumulator. The relief valve is used to limit the maximum pressure of the system, and the filter is used to ensure the cleanliness of the oil.

[0025] The mechanical actuator is a single-acting hydraulic cylinder with a push rod connected to the end of its piston rod. When high-pressure hydraulic oil enters the hydraulic cylinder, it pushes the piston and push rod to extend and open the intake valve plate. When the hydraulic oil circuit is cut off, the piston retracts under the action of the return spring, and the intake valve closes by its own spring force.

[0026] The PLC control system adopts an industrial programmable logic controller with a built-in high-speed counting module and analog input / output module. It communicates with the host computer via Ethernet or fieldbus, receives pulse signals from the speed sensor and dead center sensor, performs phase calculation, compensation duration calculation and control logic, and outputs digital signals to drive each first solenoid valve.

[0027] The speed sensor is a magnetoelectric proximity sensor, which is fixedly installed on the crankshaft housing. Its sensing end is close to the speed measuring gear on the crankshaft. The sensor outputs a pulse for each tooth the gear rotates, and the PLC control system calculates the real-time crankshaft speed based on the number of pulses per unit time.

[0028] The dead center sensor is a Hall effect proximity switch, which is fixedly installed on the crankcase at a position corresponding to the crankshaft reference phase angle (e.g., top dead center). A trigger block is installed on the crankshaft at this angle. When the trigger block passes the sensor, the sensor outputs a high-level pulse, which is the dead center signal.

[0029] The first solenoid valve is a two-position three-way high-speed solenoid valve with a response time of no more than 5ms. The oil inlet of the solenoid valve is connected to the oil outlet of the hydraulic station, the working port is connected to the oil inlet of the corresponding mechanical actuator, and the return port is connected to the oil tank. When the PLC outputs a top-open signal, the solenoid valve is energized, and the oil inlet and working port are connected. When the PLC outputs a close signal, the solenoid valve is de-energized, the working port and return port are connected, and the mechanical actuator is unloaded.

[0030] Understandably, the reference gas recirculation time of each compression component is the length of time it takes to execute gas recirculation by opening its corresponding intake valve. In other words, the reference gas recirculation time of each compression component is the reference control time of the intake valve corresponding to each crank.

[0031] S200, determine the moment when the crankshaft last rotated to the reference phase angle as the starting moment, and determine the moment when the phase angle of the crankshaft needs to be acquired as the current moment; and calculate the product of the time elapsed from the starting moment to the current moment and the crankshaft speed to determine the current phase angle of the crankshaft; The reference phase angle of the crankshaft refers to the fixed crankshaft angle position corresponding to the trigger signal of the dead center sensor during crankshaft rotation. This position serves as the starting reference zero point for subsequent phase angle calculations.

[0032] Specifically, the dead center sensor is used to send a dead center signal to the PLC control system when the crankshaft rotates to the reference phase angle; the PLC control system is used to reset the moment as the starting moment when it receives the dead center signal, and determine the moment when the phase angle of the crankshaft needs to be acquired as the current moment; and calculate the product of the time elapsed from the starting moment to the current moment and the crankshaft speed to determine the current phase angle of the crankshaft.

[0033] S300, based on the current phase angle of the crankshaft and the preset phase difference between the current phase angle of each crank and the reference phase angle of each crank relative to the crankshaft, obtains the current absolute phase angle of each crank. The preset phase difference of each crankpin relative to the reference phase angle of the crankshaft refers to the fixed angular difference between the installation angle of each crankpin on the crankshaft and the reference phase angle. This difference is determined by the geometric misalignment arrangement during crankshaft machining and assembly, and is used to determine the relative position of each crankpin in the rotation cycle.

[0034] Specifically, the PLC control system is also used to obtain the current absolute phase angle of each crank based on the current phase angle of the crankshaft and the preset phase difference between the current phase angle of the crankshaft and the reference phase angle of each crank relative to the crankshaft.

[0035] S400, based on the crankshaft speed, the preset pipeline intake pulsation compensation phase angle of each crank, and the preset damping correction coefficient, obtains the phase compensation time of each crank; wherein, the preset pipeline intake pulsation compensation phase angle is used to characterize the phase difference of intake pulsation propagation caused by the difference in the intake pipeline system corresponding to the compression assembly. Understandably, the aforementioned structure with multiple crankshafts arranged at staggered angles on the same crankshaft allows each row of cylinders to intermittently draw air at a fixed phase difference. However, due to objective differences in the length, number of bends, and pipe diameter of the intake pipes corresponding to each row of cylinders, the airflow pulsation propagation characteristics of each pipe are not the same. Furthermore, the pressure waves generated by the intake actions of adjacent rows will superimpose on each other within the shared intake pipe section, thus constituting the physical source of the pulsation superposition effect. To address this effect, a preset pipeline intake pulsation compensation phase angle is pre-calibrated based on the measured acoustic transmission characteristics of the intake pipe corresponding to each crankshaft, used to characterize the specific delay effect of that pipe section on pulsation propagation.

[0036] Specifically, the PLC control system is also used to obtain the phase compensation duration of each crank based on the crankshaft speed, the preset pipeline intake pulsation compensation phase angle of each crank, and the preset damping correction coefficient.

[0037] In one embodiment, step S400 includes: For each bend: The following formula is used to calculate the crankshaft speed, the preset pipeline intake pulsation compensation phase angle of the current crank, and the preset damping correction coefficient to obtain the phase compensation duration of the current crank. ;in, This indicates the phase compensation duration of the current crank. Indicates the crankshaft rotational speed. This indicates the preset pipeline intake pulsation compensation phase angle for the current crankshaft. This indicates the preset damping correction coefficient.

[0038] The preset damping correction coefficient is used to reflect the attenuation of pulsation amplitude caused by viscous damping and friction of the pipe wall during actual gas flow.

[0039] In one embodiment, the preset damping correction factor is corrected in the following way: S410a, collects the pulsation signal of the intake manifold and the number of compression components; Specifically, the HydroCOM stepless air volume control system also includes: multiple airflow pulsation sensors; each airflow pulsation sensor is installed on the corresponding intake pipe.

[0040] Specifically, the airflow pulsation sensor is used to collect pulsation signals from the intake duct.

[0041] The airflow pulsation sensor is a piezoresistive dynamic pressure sensor, which is installed in a pressure-sensing hole on the wall of the intake pipe via a threaded connection, with the pressure-sensing end face basically flush with the inner wall of the pipe, to accurately sense the dynamic pressure fluctuations of the airflow within the pipe. The signal output terminals of each airflow pulsation sensor are connected to the analog input module of the PLC control system, which converts the acquired pulsating pressure signal into a standard analog electrical signal (such as a 4-20mA current signal or a 0-10V voltage signal) and transmits it to the PLC control system for subsequent spectrum analysis of the pulsation signal in the intake pipe.

[0042] S420a performs spectral analysis on the pulsating signal of the intake manifold to obtain the dominant frequency and amplitude of the pulsating signal of the intake manifold. Specifically, the spectrum analysis uses Fast Fourier Transform (FFT) to extract the dominant frequency, which corresponds to the fundamental frequency component of the airflow pulsation in the intake duct, and the amplitude characterizes the intensity of the pulsation energy.

[0043] S430a, using the following formula, calculate the crankshaft speed and the number of compression components to obtain the fundamental frequency of airflow pulsation; ;in, The fundamental frequency representing airflow pulsation. Indicates the crankshaft rotational speed. Indicates the number of compression components; S440a, if the absolute value of the difference between the main frequency of the pulsating signal of the intake pipe and the fundamental frequency of the airflow pulsation is less than the preset frequency, and the amplitude of the pulsating signal of the intake pipe is greater than the preset amplitude, then the preset damping correction coefficient is increased; or if the absolute value of the difference between the main frequency of the pulsating signal of the intake pipe and the fundamental frequency of the airflow pulsation is less than the preset frequency, and the amplitude of the pulsating signal of the intake pipe is less than the preset amplitude, then the preset damping correction coefficient is decreased.

[0044] Specifically, steps S420a to S440a are all implemented through a PLC control system.

[0045] In this embodiment, by real-time acquisition and spectral analysis of the intake pipe's pulsation signal, and combining the crankshaft speed and the number of compression components, the theoretical fundamental pulsation frequency is calculated, enabling adaptive online correction of the preset damping correction coefficient. When the measured pulsation frequency matches the theoretical fundamental frequency and has a large amplitude, the damping correction coefficient is appropriately increased to enhance the phase compensation effect; when the amplitude is small, the correction coefficient is decreased to avoid overcompensation. This closed-loop correction mechanism allows the phase compensation duration to be dynamically adjusted according to the actual changes in the airflow pulsation characteristics within the pipe, effectively overcoming the problem of insufficient adaptability of fixed calibration parameters when operating conditions change, and further improving the accuracy and robustness of airflow regulation.

[0046] It is understandable that airflow pulsation requires a certain propagation time to spread from the intake confluence area to the intake ports of each compression component. This propagation time is positive, while the crankshaft rotates continuously in a fixed direction. Therefore, this positive propagation delay naturally corresponds to a positive angular offset in the phase angle coordinate system. Its value is equal to the product of the propagation delay time and the crankshaft speed. Therefore, the preset pipeline intake pulsation compensation phase angle must be positive.

[0047] In one embodiment, the preset pipeline intake pulsation compensation phase angle for each crank is determined in the following manner: For each bend: S410b, obtain the airflow pulsation propagation speed at the intake manifold area and the equivalent length of the pipeline from the intake port of the compression component corresponding to the current crank to the intake manifold area; The airflow pulsation propagation velocity at the intake confluence area refers to the phase velocity of the pressure pulsation wave propagating along the airflow direction within the intake confluence area (i.e., the common pipeline section before the convergence of branch pipelines). This velocity depends on the pressure, temperature, and density of the gas in the pipeline, as well as the pipeline's geometry and acoustic characteristics, and can be obtained through field measurements or theoretical calculations based on a pipeline acoustic model.

[0048] The equivalent length of the pipeline from the intake port of the compressor assembly corresponding to the current crankshaft to the intake manifold area refers to the actual geometric length of the pipeline from the intake valve port of the compressor assembly along the intake pipeline back to the intake manifold area (i.e., the junction of each branch pipeline or the end of the common pipeline), after correction for the equivalent length of local resistance elements such as elbows, reducers, and valves. This equivalent length is used to characterize the actual propagation path length of the pulsating wave in this section of the pipeline.

[0049] S420b, calculate the ratio of the equivalent pipe length corresponding to the current crank to the airflow pulsation propagation speed at the intake confluence region, and obtain the pulsation propagation delay time of the current crank; S430b calculates the product of the current crankshaft's pulsation propagation delay time and the crankshaft's rotational speed to obtain the preset pipeline intake pulsation compensation phase angle for the current crankshaft.

[0050] In this embodiment, by individually acquiring the equivalent length of the pipeline from the corresponding air inlet to the air intake confluence area and the airflow pulsation propagation velocity in that area for each crank, and calculating the unique pulsation propagation delay time and corresponding compensation phase angle for each crank, refined compensation for the differences in the air intake pipelines of each compression assembly is achieved. This differentiated calibration method fully considers the differences in layout, length, and local resistance characteristics of each air intake pipeline, avoiding the phase mismatch problem caused by using a uniform compensation value, and eliminating the adverse effects of pipeline system differences on air volume regulation accuracy from the source.

[0051] S500, calculate the difference between the reference gas recirculation time of each compression component and the phase compensation time of each crank, and obtain the actual gas recirculation time of each compression component; Specifically, the reference gas recirculation time is the theoretical recirculation control time of each compression component under standard operating conditions, without considering pipeline pulsation phase deviation. The phase compensation time represents the crankshaft angle time corresponding to the intake pulsation phase delay caused by intake pipeline differences. Since this delay causes the actual airflow to arrive at the intake valve port to lag behind the crankshaft phase detection time, this lag time must be subtracted from the reference recirculation time to ensure that the actual gas recirculation action is synchronized with the actual airflow pulsation phase in the cylinder. Adding the two together would further lag the recirculation action behind the actual pulsation phase, leading to control misalignment. Therefore, difference calculation is used to obtain the actual gas recirculation time.

[0052] Specifically, the PLC control system also calculates the difference between the reference gas recirculation time of each compression component and the phase compensation time of each crank to obtain the actual gas recirculation time of each compression component.

[0053] S600: When the current absolute phase angle of any crank reaches the intake termination phase angle corresponding to that crank, control the compression component corresponding to that crank to start gas recirculation, and after waiting for the actual gas recirculation time of the compression component corresponding to that crank, control the compression component corresponding to that crank to stop gas recirculation.

[0054] The intake termination phase angle of the crank refers to the crankshaft angle corresponding to the position of the piston when the compression component driven by the crank completes the intake stroke. When the current absolute phase angle of the crank reaches this angle, it indicates that the intake stroke has ended and the intake valve needs to be opened to start the air volume regulation.

[0055] Specifically, the hydraulic station is used to provide high-pressure hydraulic oil; each mechanical actuator is used to open or release the intake valve of the corresponding crank under the drive of the hydraulic oil; each first solenoid valve is used to, upon receiving an open control signal, open the hydraulic line corresponding to the crank, so that the hydraulic station supplies hydraulic oil to the mechanical actuator corresponding to the crank, thereby opening the corresponding intake valve; or, upon receiving a close control signal, cut off the hydraulic line corresponding to the crank, so that the hydraulic station stops supplying hydraulic oil to the mechanical actuator, thereby closing the intake valve corresponding to the crank; the PLC control system is also used to, when the current absolute phase angle of any crank reaches the intake termination phase angle corresponding to the crank, send an open control signal to the first solenoid valve corresponding to the crank, and after the actual control time of the intake valve corresponding to the crank, send a close control signal to the first solenoid valve corresponding to the crank.

[0056] In one embodiment, prior to step S600, the method further includes: a1, collect the exhaust pressure of each compression component; Specifically, the HydroCOM continuously variable air volume control system also includes: multiple second pressure sensors; each second pressure sensor is located at the exhaust port of the corresponding compression component.

[0057] Specifically, each second pressure sensor is used to monitor the exhaust pressure of each compression component.

[0058] For each compression component: a2. If the exhaust pressure of the current compression component is less than the corresponding preset target pressure, then reduce the actual gas recirculation time of the current compression component; or if the exhaust pressure of the current compression component is greater than the corresponding preset target pressure, then increase the actual gas recirculation time of the current compression component.

[0059] Specifically, the PLC control system is also used to reduce the actual control time of the intake valve corresponding to each crank if the current exhaust pressure of the compression assembly is less than the corresponding preset target pressure; or to increase the actual control time of the intake valve corresponding to each crank if the current exhaust pressure of the compression assembly is greater than the corresponding preset target pressure.

[0060] Understandably, while the aforementioned phase compensation duration can eliminate intake pulsation phase deviations caused by pipeline differences, it is essentially feedforward compensation based on preset calibration parameters. It cannot respond in real-time to dynamic disturbances such as upstream supply pressure fluctuations, downstream load changes, or gas composition alterations during operation. Therefore, further correction is needed based on phase compensation. Among numerous measurable parameters, exhaust pressure most directly and sensitively reflects the instantaneous balance between compressor supply and user consumption (pressure decrease indicates insufficient intake, while pressure increase indicates excessive intake). Simultaneously, exhaust pressure itself is a core target parameter that upstream process equipment must strictly control. Furthermore, pressure sensors offer engineering advantages such as fast response, low cost, and ease of independent installation for each compression component. Therefore, the deviation between the measured exhaust pressure and the preset target pressure is used as the adjustment basis to perform a secondary fine-tuning of the actual control duration after feedforward compensation.

[0061] In one embodiment, the stepless gas volume adjustment method for the reciprocating compressor further includes: b1, collects the hydraulic oil pressure of the hydraulic oil circuit that controls the gas return of each compression component; Specifically, the reciprocating compressor also includes multiple second solenoid valves; the HydroCOM stepless air volume regulation system also includes multiple vibration monitoring modules, multiple first pressure sensors, and a safety interlock control system; a bypass return pipeline is connected between the input and output ends of each compression component, each vibration monitoring module and each second solenoid valve is located on the corresponding bypass return pipeline, each first pressure sensor is located on the corresponding hydraulic pipeline, and multiple vibration monitoring modules and multiple first pressure sensors are all electrically connected to the safety interlock control system.

[0062] The first pressure sensor is a diffused silicon pressure transmitter, which is installed near the mechanical actuator in each hydraulic pipeline. It is used to monitor the pressure of the supplied hydraulic oil in real time and convert the pressure value into a 4-20mA standard electrical signal to be transmitted to the safety interlock control system.

[0063] It is understandable that the safety interlock control system and the aforementioned PLC control system do not belong to the same control loop, but are independently set safety protection units; they have independent power supplies, processors and input / output channels, and do not depend on the calculation results of the PLC, so as to ensure that the protection action can still be reliably executed when the PLC fails or communication is interrupted.

[0064] Specifically, each first pressure sensor is used to monitor the pressure of the corresponding hydraulic line.

[0065] b2, when the hydraulic oil pressure of the hydraulic oil circuit controlling the gas return of any compression component is less than the preset pressure, the air inlet and exhaust port of the compression component are connected.

[0066] Specifically, the safety interlock control system is used to send an opening command to the corresponding second solenoid valve when the hydraulic oil pressure of the corresponding hydraulic line is less than the preset pressure; each second solenoid valve is used to open the corresponding bypass return line when it receives the opening command.

[0067] Understandably, when the hydraulic oil pressure is lower than the preset pressure threshold, it indicates that the hydraulic station cannot properly drive the mechanical actuator to complete the opening action of the intake valve. When the above-mentioned unsafe conditions are triggered, the safety interlock control system opens the bypass return pipeline, allowing the high-pressure gas discharged from the compression assembly to flow directly back to the intake end, thereby quickly reducing the load on the compressor unit and preventing equipment damage.

[0068] In this embodiment of the invention, the current phase angle is recalculated by taking the moment when the crankshaft last rotated to the reference phase angle as the starting point, which completely eliminates the accumulated error caused by traditional continuous timing. At the same time, a preset pipeline intake pulsation compensation phase angle and a preset damping correction coefficient are introduced for each crank, which accurately compensates for the intake pulsation propagation phase difference caused by the difference in the intake pipeline system. This avoids the inability to effectively eliminate the superposition of intake pulsations caused by detection errors and pipeline phase deviations, thereby accurately ensuring the stability of the compressor's air supply.

[0069] Example 2 Based on the same inventive concept, such as Figure 3 As shown, this embodiment of the invention also provides a stepless air volume regulating device 200 for a reciprocating compressor. The reciprocating compressor includes multiple compression components and a crankshaft assembly. The crankshaft assembly includes multiple cranks disposed on the same crankshaft, and each crank is staggered from the others by a preset angle. Each crank is connected to a corresponding compression component, including: The parameter acquisition module 210 is used to acquire the crankshaft speed and the reference gas reflux time of each compression component; The phase calculation module 220 is used to determine the moment when the crankshaft last rotated to the reference phase angle as the starting moment, and to determine the moment when the phase angle of the crankshaft needs to be acquired as the current moment; and to calculate the product of the time elapsed from the starting moment to the current moment and the crankshaft rotation speed to determine the current phase angle of the crankshaft. The phase calibration module 240 is used to obtain the current absolute phase angle of each crank based on the current phase angle of the crankshaft and the preset phase difference between the current phase angle of each crank and the reference phase angle of each crank relative to the crankshaft. The compensation calculation module 250 is used to obtain the phase compensation duration of each crank based on the crankshaft speed, the preset pipeline intake pulsation compensation phase angle of each crank, and the preset damping correction coefficient; wherein, the preset pipeline intake pulsation compensation phase angle is used to characterize the phase difference of intake pulsation propagation caused by the difference in the intake pipeline system corresponding to the compression component. The duration correction module 260 is used to calculate the difference between the reference gas recirculation time of each compression component and the phase compensation time of each crank, so as to obtain the actual gas recirculation time of each compression component. The recirculation control module 270 is used to control the compression component corresponding to any crank to start gas recirculation when the current absolute phase angle of any crank reaches the intake termination phase angle corresponding to the crank, and to control the compression component corresponding to the crank to stop gas recirculation after waiting for the actual gas recirculation time of the compression component corresponding to the crank.

[0070] In one embodiment, the compensation calculation module 250 is specifically used for: For each bend: The following formula is used to calculate the crankshaft speed, the preset pipeline intake pulsation compensation phase angle of the current crank, and the preset damping correction coefficient to obtain the phase compensation duration of the current crank. ;in, This indicates the phase compensation duration of the current crank. Indicates the crankshaft rotational speed. This indicates the preset pipeline intake pulsation compensation phase angle for the current crankshaft. This indicates the preset damping correction coefficient.

[0071] It should be understood that this device corresponds to the stepless air volume adjustment method embodiment of the reciprocating compressor described above, and is capable of performing the various steps involved in the above method embodiment. The specific functions of this device can be found in the description above, and detailed descriptions are omitted here to avoid repetition. The device includes at least one software function module that can be stored in memory or embedded in the device's operating system (OS) in the form of software or firmware.

[0072] Example 3 Based on the same inventive concept, embodiments of the present invention also provide an electronic device, including: a processor and a memory, the memory storing machine-readable instructions executable by the processor, the machine-readable instructions executing the above-described stepless air volume regulation method of the reciprocating compressor when executed by the processor.

[0073] In a typical configuration, an electronic device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0074] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0075] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0076] Example 4 Based on the same inventive concept, embodiments of the present invention also provide a computer-readable storage medium storing computer instructions, which, when executed on a computer, cause the computer to perform the above-described stepless air volume regulation method for a reciprocating compressor.

[0077] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0078] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0079] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0080] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0081] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the embodiments of the present invention will not describe the various possible combinations separately.

[0082] In addition, the functional modules in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0083] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0084] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A method for infinitely adjusting the air volume of a reciprocating compressor, the reciprocating compressor comprising a plurality of compression assemblies and a crankshaft assembly, the crankshaft assembly comprising a plurality of crank webs arranged on a same crankshaft and arranged at a preset angle offset from each other, each of the crank webs being connected to a corresponding compression assembly, characterized in that, The method includes: Collect crankshaft rotation speed and reference gas reflux time for each compression component; The starting time is determined by identifying the moment when the crankshaft last rotated to the reference phase angle, and the current time is determined by identifying the moment when the crankshaft phase angle needs to be acquired. The current phase angle of the crankshaft is determined by multiplying the elapsed time from the starting time to the current time by the crankshaft rotation speed. Based on the current phase angle of the crankshaft and the preset phase difference between each crank and the reference phase angle of the crankshaft, the current absolute phase angle of each crank is obtained. Based on the crankshaft speed, the preset pipeline intake pulsation compensation phase angle of each crank, and the preset damping correction coefficient, the phase compensation time of each crank is obtained; among which, the preset pipeline intake pulsation compensation phase angle is used to characterize the phase difference of intake pulsation propagation caused by the difference in the intake pipeline system corresponding to the compression assembly. The difference between the reference gas recirculation time of each compression component and the phase compensation time of each crank is calculated to obtain the actual gas recirculation time of each compression component. When the current absolute phase angle of any crank reaches the intake termination phase angle corresponding to that crank, the compressor component corresponding to that crank is controlled to start gas recirculation, and after waiting for the actual gas recirculation time of the compressor component corresponding to that crank, the compressor component corresponding to that crank is controlled to stop gas recirculation.

2. The infinitely variable displacement method of a reciprocating compressor according to claim 1, characterized by, Based on the crankshaft speed, the preset pipeline intake pulsation compensation phase angle for each crank, and the preset damping correction coefficient, the phase compensation duration for each crank is obtained, including: For each bend: The following formula is used to calculate the crankshaft speed, the preset pipeline intake pulsation compensation phase angle of the current crank, and the preset damping correction coefficient to obtain the phase compensation duration of the current crank. ; wherein denotes the phase compensation duration of the current crank, denotes the rotational speed of the crankshaft, denotes the preset intake pulse compensation phase angle of the current crank, denotes the preset damping correction factor.

3. The infinitely variable displacement method of a reciprocating compressor according to claim 1, characterized by, The preset damping correction factor is corrected in the following way: Collect the pulsation signal of the intake manifold and the number of compression components; Spectral analysis was performed on the pulsating signal of the intake manifold to obtain the dominant frequency and amplitude of the pulsating signal. The fundamental frequency of airflow pulsation is obtained by calculating the crankshaft speed and the number of compression components using the following formula; ; wherein represents the base frequency of the gas flow pulsation, represents the rotational speed of the crankshaft, represents the number of compression assemblies; If the absolute value of the difference between the dominant frequency of the intake manifold pulsation signal and the fundamental frequency of the airflow pulsation is less than the preset frequency, and the amplitude of the intake manifold pulsation signal is greater than the preset amplitude, then the preset damping correction coefficient is increased; or If the absolute value of the difference between the main frequency of the pulsation signal in the intake pipe and the fundamental frequency of the airflow pulsation is less than the preset frequency, and the amplitude of the pulsation signal in the intake pipe is less than the preset amplitude, then the preset damping correction coefficient is reduced.

4. The stepless air volume adjustment method for a reciprocating compressor according to claim 1, characterized in that, The preset pipeline intake pulsation compensation phase angle for each crank is determined in the following way: For each bend: Obtain the airflow pulsation propagation speed at the intake manifold area and the equivalent length of the pipeline from the intake port of the compression component corresponding to the current crank to the intake manifold area; Calculate the ratio of the equivalent pipe length corresponding to the current crank to the airflow pulsation propagation speed at the intake confluence region to obtain the pulsation propagation delay time of the current crank. The preset pipeline intake pulsation compensation phase angle of the current crankshaft is obtained by multiplying the current crankshaft rotational speed by the pulsation propagation delay time of the current crankshaft.

5. The stepless air volume adjustment method for a reciprocating compressor according to claim 1, characterized in that, Before the step of when the current absolute phase angle of any crank reaches the intake termination phase angle corresponding to that crank, the method further includes: Collect the exhaust pressure of each compression component; For each compression component: If the current exhaust pressure of the compression assembly is less than the corresponding preset target pressure, then reduce the actual gas recirculation time of the current compression assembly; or If the exhaust pressure of the current compression component is greater than the corresponding preset target pressure, then the actual gas recirculation time of the current compression component is increased.

6. The stepless air volume adjustment method for a reciprocating compressor according to claim 1, characterized in that, The method further includes: Collect and control the hydraulic oil pressure of the hydraulic oil circuit that controls the gas return of each compression component; When the hydraulic oil pressure in the hydraulic circuit controlling the gas return of any compression component is less than the preset pressure, the air inlet and outlet of that compression component are connected.

7. A stepless air volume regulating device for a reciprocating compressor, the reciprocating compressor comprising multiple compression components and a crankshaft assembly, the crankshaft assembly comprising multiple cranks disposed on the same crankshaft, and the cranks being staggered from each other by a predetermined angle, each crank being connected to a corresponding compression component, characterized in that, include: The parameter acquisition module is used to acquire the crankshaft speed and the reference gas reflux time of each compression component; The phase calculation module is used to determine the moment when the crankshaft last rotated to the reference phase angle as the starting moment, and to determine the moment when the phase angle of the crankshaft needs to be obtained as the current moment; and to calculate the product of the time elapsed from the starting moment to the current moment and the crankshaft speed to determine the current phase angle of the crankshaft. The phase calibration module is used to obtain the current absolute phase angle of each crank based on the current phase angle of the crankshaft and the preset phase difference between each crank and the reference phase angle of each crank relative to the crankshaft. The compensation calculation module is used to obtain the phase compensation duration of each crank based on the crankshaft speed, the preset pipeline intake pulsation compensation phase angle of each crank, and the preset damping correction coefficient; wherein, the preset pipeline intake pulsation compensation phase angle is used to characterize the phase difference of intake pulsation propagation caused by the difference in the intake pipeline system corresponding to the compression assembly. The duration correction module is used to calculate the difference between the reference gas recirculation time of each compression component and the phase compensation time of each crank, so as to obtain the actual gas recirculation time of each compression component. The recirculation control module is used to control the compression component corresponding to any crank to start gas recirculation when the current absolute phase angle of any crank reaches the intake termination phase angle corresponding to that crank, and to control the compression component corresponding to the crank to stop gas recirculation after waiting for the actual gas recirculation time of the compression component corresponding to that crank.

8. The stepless gas volume regulating device for a reciprocating compressor according to claim 7, characterized in that, The compensation calculation module is specifically used for: For each bend: The following formula is used to calculate the crankshaft speed, the preset pipeline intake pulsation compensation phase angle of the current crank, and the preset damping correction coefficient to obtain the phase compensation duration of the current crank. ;in, This indicates the phase compensation duration of the current crank. Indicates the crankshaft rotational speed. This indicates the preset pipeline intake pulsation compensation phase angle for the current crankshaft. This indicates the preset damping correction coefficient.

9. An electronic device, characterized in that, include: A processor and a memory, the memory storing machine-readable instructions executable by the processor, which, when executed by the processor, perform the stepless air volume regulation method of the reciprocating compressor according to any one of claims 1-6.

10. A computer-readable storage medium storing computer instructions, characterized in that, When the computer instructions are executed on the computer, the computer performs the stepless air volume regulation method of the reciprocating compressor according to any one of claims 1-6.

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