Plunger pump system and pressure pulsation compensation method thereof, and fracturing equipment

Abstract

A plunger pump system, a pressure pulsation compensation method thereof, and a fracturing device. The plunger pump system includes a first plunger pump and a fluid pressure compensation structure. The fluid pressure compensation structure is configured to compensate for the pressure pulsation of the fluid output from the output end of the first plunger pump. The fluid pressure compensation structure includes at least one linear motor and a second plunger pump driven by at least one linear motor, and the output end of the second plunger pump is connected to the output end of the first plunger pump. The plunger pump system provided by the embodiment of the present disclosure adds a fluid pressure compensation structure having a linear motor and a second plunger pump. The linear motor is small in size and is convenient for integration with the second plunger pump to achieve a compact design. The linear motor is easy to adjust and control to achieve compensation for the pressure pulsation of the fluid output by the first plunger pump.

Description

Technical Field

[0001] At least one embodiment of the present disclosure relates to a plunger pump system, a pressure pulsation compensation method thereof, and fracturing equipment. Background Art

[0002] Currently, in multi-cylinder plunger pumps, the cyclical motion of the crankshaft driving the plungers generates flow pulsations, which in turn cause pressure pulsations in the high-pressure, pulsating fluid discharged by the multi-cylinder plunger pump. This pressure pulsation manifests as continuous vibration, reducing the service life of piping and components, and further damaging equipment and systems connected to the pump's outlet. Furthermore, the pressure pulsations of high-pressure, pulsating fluids are accompanied by high levels of noise, which can easily cause environmental pollution. Summary of the Invention

[0003] At least one embodiment of the present disclosure provides a plunger pump system, a pressure pulsation compensation method thereof, and fracturing equipment.

[0004] At least one embodiment of the present disclosure provides a plunger pump system, comprising a first plunger pump and a fluid pressure compensation structure. The fluid pressure compensation structure is configured to compensate for pressure pulsations of a fluid outputted from an output end of the first plunger pump. The fluid pressure compensation structure comprises at least one linear motor and a second plunger pump driven by the at least one linear motor, wherein the output end of the second plunger pump is connected to the output end of the first plunger pump.

[0005] For example, according to an embodiment of the present disclosure, the number of the second plunger pumps driven by each linear motor is two, the two ends of the mover of the linear motor are respectively connected to and drive two second plunger pumps, the linear motor and the two second plunger pumps are arranged in a straight line, and the linear motor is configured to reciprocate linearly between the two second plunger pumps.

[0006] For example, according to an embodiment of the present disclosure, the at least one linear motor includes a plurality of linear motors, and the number of the second plunger pump driven by at least one of the plurality of linear motors is one.

[0007] For example, according to an embodiment of the present disclosure, the first plunger pump includes a multi-cylinder plunger pump.

[0008] For example, according to an embodiment of the present disclosure, the second plunger pump includes a single-cylinder plunger pump.

[0009] For example, according to an embodiment of the present disclosure, the plunger pump system further includes a controller electrically connected to the linear motor. The controller is configured to adjust the speed of the linear motor according to the rotational speed of the first plunger pump so that the period of the pressure pulsation of the fluid output from the output end of the second plunger pump is equal to the period of the pressure pulsation of the fluid output from the output end of the first plunger pump, and the two are in opposite phases; and / or, the controller is configured to adjust the thrust of the linear motor according to the pressure of the fluid output from the first plunger pump so that the pressure amplitude of the pressure pulsation of the fluid output from the output end of the second plunger pump is equal to the pressure amplitude of the pressure pulsation of the fluid output from the output end of the first plunger pump, and the two are in opposite phases.

[0010] For example, according to an embodiment of the present disclosure, the plunger pump system further includes a speed acquisition unit and / or a pressure acquisition unit. The speed acquisition unit is connected to the first plunger pump and is configured to acquire the speed of the first plunger pump. The pressure acquisition unit is connected to the first plunger pump and is configured to acquire a pressure pulsation signal of the fluid output by the first plunger pump.

[0011] For example, according to an embodiment of the present disclosure, the controller is electrically connected to the speed acquisition unit, and the controller includes a linear conversion unit and a speed adjustment unit. The linear conversion unit is configured to perform linear conversion calculation based on the speed of the first plunger pump to obtain the pulsation period of the fluid output by the fluid pressure compensation structure; the speed adjustment unit is configured to calculate the preset speed of the linear motor based on the pulsation period of the fluid, and the controller adjusts the speed of the linear motor according to the preset speed.

[0012] For example, according to an embodiment of the present disclosure, the pressure acquisition unit is electrically connected to the controller, and the controller is configured to control the thrust of the linear motor according to the pressure pulsation signal acquired by the pressure acquisition unit.

[0013] For example, according to an embodiment of the present disclosure, the input end of the second plunger pump is connected to the input end of the first plunger pump.

[0014] At least one embodiment of the present disclosure provides a fracturing device, comprising any of the above-mentioned plunger pump systems.

[0015] At least one embodiment of the present disclosure provides a pressure pulsation compensation method applied to the above-mentioned plunger pump system, including: adjusting the speed of the linear motor according to the rotational speed of the first plunger pump so that the period of the pressure pulsation of the fluid output from the output end of the second plunger pump is equal to the period of the pressure pulsation of the fluid output from the output end of the first plunger pump, and the two are in opposite phases; and / or, adjusting the thrust of the linear motor according to the pressure of the fluid output from the first plunger pump so that the pressure amplitude of the pressure pulsation of the fluid output from the output end of the second plunger pump is equal to the pressure amplitude of the pressure pulsation of the fluid output from the output end of the first plunger pump, and the two are in opposite phases.

[0016] For example, according to an embodiment of the present disclosure, adjusting the speed of the linear motor according to the rotational speed of the first plunger pump includes: collecting the rotational speed of the first plunger pump; performing linear conversion calculation based on the rotational speed of the first plunger pump to obtain the pulsation period of the fluid output by the fluid pressure compensation structure; and calculating the preset speed of the linear motor based on the pulsation period of the fluid, and adjusting the speed of the linear motor according to the preset rotational speed.

[0017] For example, according to an embodiment of the present disclosure, adjusting the thrust of the linear motor according to the pressure of the fluid output by the first plunger pump includes: collecting a pressure pulsation signal of the fluid output by the first plunger pump; and controlling the thrust of the linear motor according to the pressure pulsation signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings of the embodiments will be briefly introduced below. Obviously, the drawings in the following description only relate to some embodiments of the present disclosure, rather than limiting the present disclosure.

[0019] Figure 1 A structural block diagram of a plunger pump system according to an embodiment of the present disclosure;

[0020] Figure 2 A schematic diagram of a fluid pressure compensation structure provided according to an example of an embodiment of the present disclosure;

[0021] Figure 3 for Figure 1 The schematic diagram of the electrical connection between the controller and the speed acquisition unit shown;

[0022] Figure 4 for Figure 1 A schematic diagram of at least a portion of the process of the controller adjusting the speed of the linear motor according to the rotational speed of the first piston pump is shown;

[0023] Figure 5 for Figure 1 A schematic diagram of the electrical connection between the controller and the pressure acquisition unit shown; and

[0024] Figure 6 The figure is a structural block diagram of a fracturing device provided according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0025] To make the purpose, technical solutions, and advantages of the embodiments of the present disclosure more clear, the technical solutions of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0026] Unless otherwise defined, the technical or scientific terms used in this disclosure shall have the usual meanings understood by persons of ordinary skill in the field to which this disclosure belongs. The words "first", "second" and similar terms used in this disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Words such as "include" or "comprise" mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. In this disclosure, the names of "first plunger pump" and "second plunger pump" are interchangeable, one of which is driven by a linear motor and the other is driven by an electric motor or a turbine engine as a power source.

[0027] There are two methods for eliminating flow pulsation: passive compensation and active compensation. Passive compensation involves installing an energy storage buffer in the pulsating pipeline. Based on the pressure of the system generating the flow pulsation, the pressure of the energy storage buffer is set to a certain level to reduce the amplitude of the system pressure pulsation. Active compensation involves adding an external power source to the system to introduce a secondary pulsation with equal amplitude and period, but opposite phase, to the pulsating pressure, thereby eliminating the initial pulsation in the system.

[0028] Active pulsation compensation includes three forms: inflow compensation, diversion compensation and diversion inflow compensation. Active pulsation compensation actively controls the flow so that the system ultimately outputs a smooth flow. Inflow active compensation refers to adding additional energy to the system, such as adding a flow supplement pump to the system. The pump's supply is controlled by a servo valve to supplement the trough of the flow pulsation in the system's pipeline, so that the flow in the pipeline tends to be stable and the pressure pulsation in the system is reduced. Diversion active compensation refers to adjusting the valve opening in a pipeline to divert part of the peak flow to achieve the purpose of smooth flow output and stable pressure. Diversion inflow active compensation couples the diversion type and the inflow type, that is, the fluid output from the pipeline is diverted when it is at the peak flow value, and supplemented when it is at the valley value of the flow value to maintain the stability of the system flow and pressure, thereby achieving the effect of reducing pressure pulsation.

[0029] In actual use, passive pulsation compensation requires an excessively large buffer installed in the discharge pipeline, and its effectiveness in compensating low-frequency pulsations is poor. Piping vibration is significant during high-pressure, high-displacement operations. Active pulsation compensation, due to its complex process, is only rarely used in systems operating around 20 MPa and has no substantial application in operations exceeding 50 MPa. This results in a short lifespan for piping and equipment, requiring frequent replacement.

[0030] During the research, the inventors of the present application found that the working pressure of the multi-cylinder plunger pump is very high. If a diversion-type active compensation method is used, the discharge process is highly dangerous and easily wears out the injection device, resulting in a reduced life of the equipment.

[0031] The embodiments of the present disclosure provide a plunger pump system and a pressure pulsation compensation method and fracturing equipment thereof. The plunger pump system includes a first plunger pump and a fluid pressure compensation structure. The fluid pressure compensation structure is configured to compensate for the pressure pulsation of the fluid output from the output end of the first plunger pump. The fluid pressure compensation structure includes at least one linear motor and a second plunger pump driven by at least one linear motor, and the output end of the second plunger pump is connected to the output end of the first plunger pump. The plunger pump system provided by the embodiment of the present disclosure adds a fluid pressure compensation structure having a linear motor and a second plunger pump. The linear motor is small in size and is convenient for integration with the second plunger pump to achieve a compact design. The linear motor is easy to adjust and control to achieve compensation for the pressure pulsation of the fluid output by the first plunger pump.

[0032] The plunger pump system, pressure pulsation compensation method, and fracturing equipment provided by the embodiments of the present disclosure are described below with reference to the accompanying drawings.

[0033] Figure 1 FIG. 1 is a structural block diagram of a plunger pump system according to an embodiment of the present disclosure. Figure 1As shown, the plunger pump system includes a first plunger pump 100 and a fluid pressure compensation structure 200. The fluid pressure compensation structure 200 is configured to compensate for the pressure pulsation of the fluid output from the output end 101 of the first plunger pump 100. The fluid pressure compensation structure 200 includes at least one linear motor 210 and a second plunger pump 220 driven by at least one linear motor 210. The output end 221 of the second plunger pump 220 is connected to the output end 101 of the first plunger pump 100, so that the fluid output from the output end 221 of the second plunger pump 220 compensates for the pressure pulsation of the fluid output from the output end 101 of the first plunger pump 100. The plunger pump system provided by the embodiment of the present disclosure adds a fluid pressure compensation structure having a linear motor and a second plunger pump. The linear motor is small in size and is convenient for integration with the second plunger pump to achieve a compact design. The linear motor is easy to adjust and control to achieve compensation for the pressure pulsation of the fluid output by the first plunger pump.

[0034] The fluid pressure compensation system including the linear motor and the second plunger pump adopts an inflow-type active compensation method. The second plunger pump column driven by the linear motor can compensate for the pressure artery of the fluid output by the first plunger pump. The plunger pump system provided by the embodiment of the present disclosure can avoid the noise caused by the discharge of high-pressure fluid and the wear of the equipment connected to the output end of the first plunger pump by using the inflow-type active compensation method. In addition, the use of a linear motor to drive the second plunger pump can achieve pressure pulsation compensation with a smaller displacement.

[0035] For example, when the first plunger pump 100 is working, mechanical energy is directly converted into pressure energy for conveying liquid through the plunger pump. For example, the first plunger pump 100 may include a power end assembly 110 and a hydraulic end assembly 120, the hydraulic end assembly includes a plunger and a valve box, the power end assembly includes a crankshaft, a connecting rod, a slide rail and a crosshead, and power is transmitted from the crosshead to the plunger. For example, a pull rod can be set between the plunger and the crosshead, the pull rod is fixed on the crosshead, the plunger is fixed on the pull rod, the crosshead reciprocates inside the slide rail, and the crosshead drives the plunger to reciprocate inside the hydraulic end assembly (for example, inside the valve box) through the pull rod, so that the liquid is sucked into the pump rod and discharged into the high-pressure pipeline, thereby realizing the suction of low-pressure fluid and the discharge of high-pressure fluid. In addition, in some examples, the plunger can also be directly mounted on the crosshead inside the power end assembly. However, the structure of the above-mentioned first plunger pump is only exemplary, and a plunger pump of any suitable structure can be selected according to the first plunger pump in the embodiment of the present disclosure.

[0036] For example, the output end 101 of the first plunger pump 100 may refer to a port through which the first plunger pump 100 discharges high-pressure fluid.

[0037] For example, the first plunger pump 100 includes a multi-cylinder plunger pump. For example, the multi-cylinder plunger pump may include a multi-cylinder valve box. For example, Figure 1The multi-cylinder valve box is schematically shown to include a three-cylinder valve box, but is not limited thereto. The multi-cylinder valve box may also include a two-cylinder valve box, a four-cylinder valve box, a five-cylinder valve box, a six-cylinder valve box, or a seven-cylinder valve box.

[0038] For example, Figure 1 As shown, the plunger pump system further includes a power source 300, which is configured to drive the first plunger pump 100. For example, the power source 300 can be connected to the power end of the first plunger pump 100 and configured to provide power to the power end of the first plunger pump 100. For example, the power source can be an electric motor or a turbine engine, and the embodiments of the present disclosure are not limited thereto.

[0039] For example, Figure 1 As shown, each linear motor 210 drives two second plunger pumps 220. For example, each linear motor 210 can be a double-acting linear motor, i.e., one linear motor 210 drives two second plunger pumps 220, and the linear motor 210 is located between the two second plunger pumps 220. For example, the two ends of the linear motor 210's mover are respectively connected to and drive the two second plunger pumps 220. The linear motor 210 and the two second plunger pumps 220 are arranged in a straight line, and the mover of the linear motor 210 is configured to reciprocate linearly between the two second plunger pumps 220. The linear motor can directly drive the second plunger pumps by utilizing its linear motion characteristics.

[0040] For example, the second plunger pump 220 includes a hydraulic end assembly, and the linear motor 210 can be connected to the hydraulic end assembly through a connecting assembly. For example, the hydraulic end assembly can include a plunger and a valve box. For example, the connecting assembly can include a plunger connector, a support rod and a mover connector, one end of the support rod is connected to the plunger connector, the other end of the support rod is connected to the mover connector, the other end of the plunger connector is connected to the plunger, and the other end of the mover connector is connected to the mover of the linear motor. The linear motor can drive the plunger to reciprocate in the valve box through the connecting assembly, so that the liquid is sucked into the pump cylinder and discharged at high pressure, thereby realizing the suction of low-pressure fluid and the discharge of high-pressure fluid. Of course, the embodiments of the present disclosure are not limited to this, and the mover of the linear motor can also be directly connected to the plunger of the second plunger pump.

[0041] For example, the second plunger pump 220 may include a single-cylinder plunger pump. For example, the two ends of the mover of the linear motor 210 are connected to and drive two single-cylinder plunger pumps. For example, one embodiment of the present disclosure uses a double-acting linear motor to drive two single-cylinder plunger pumps. The linear motion characteristics of the linear motor facilitate integration with the double-acting single-cylinder plunger pump, resulting in a compact design and ease of implementation.

[0042] For example, the output end 221 of the second plunger pump 220 may refer to a port through which the second plunger pump 220 discharges high-pressure fluid. For example, the output end 101 of the first plunger pump 100 being in communication with the output end 221 of the second plunger pump 220 may refer to the communication between the pipeline for discharging high-pressure fluid from the first plunger pump 100 and the pipeline for discharging high-pressure fluid from the second plunger pump 220 so that the high-pressure fluids discharged from the pipelines can merge, thereby enabling the fluid output from the second plunger pump 220 to compensate for the pressure pulsation of the fluid output from the first plunger pump 100.

[0043] For example, Figure 1 As shown, the input end 222 of the second plunger pump 220 is connected to the input end 102 of the first plunger pump 100. For example, the input end 102 of the first plunger pump 100 may refer to the port of the first plunger pump 100 through which the low-pressure fluid flows, the input end 222 of the second plunger pump 220 may refer to the port through which the low-pressure fluid flows from the second plunger pump 220, and the input end 222 of the second plunger pump 220 being connected to the input end 102 of the first plunger pump 100 may refer to the pipeline through which the low-pressure fluid flows from the first plunger pump 100 being connected to the pipeline through which the low-pressure fluid flows from the second plunger pump 220, which can facilitate the design of the plunger pump system. The embodiments of the present disclosure are not limited to this, and the input end of the second plunger pump may not be connected to the input end of the first plunger pump, and the two may be separated from each other, and low-pressure fluid may be sucked in from different pipelines.

[0044] For example, the linear motor 210 drives the second plunger pump 220, which has many advantages. For example, the intermediate conversion mechanism for converting rotational motion into linear motion can be eliminated, the overall structure is simplified, the weight and volume of the fluid pressure compensation structure are reduced, costs are saved, and the maintenance and maintenance of the second plunger pump are convenient; for example, direct transmission can be achieved when linear motion is required, thereby eliminating various positioning errors caused by the intermediate links, so the positioning accuracy of the linear motor is high; for example, the linear motor has a fast response speed, high sensitivity, and good follow-up performance; for example, the linear motor has less mechanical friction loss, so there are fewer failures and no maintenance, so it is safe and reliable to work and has a long service life.

[0045] For example, the linear motor may include a DC linear motor, an AC linear motor, a linear asynchronous motor, a linear synchronous motor, or a linear stepping motor. For example, the linear motor may be a flat linear motor, including a mover, a stator, and a guide rail, wherein the guide rail is fixed and the stator drives the mover to reciprocate on the guide rail.

[0046] For example, the left and right ends of the double-acting linear motor 210's mover are directly connected to a plunger. Each double-acting linear motor alternately drives the two plungers on its left and right sides, which in turn drive the second plunger pumps 2201 and 2202 located on either side of the linear motor 210. The output ends of the second plunger pumps 2201 and 2202 are both connected to the output end of the first plunger pump 100. For example, the linear motor 210 drives the single-cylinder plunger pumps on both sides (i.e., the two second plunger pumps) to operate. When the mover of the linear motor 210 moves to one side, the second plunger pump 2202 inhales low-pressure fluid, and the output end of the second plunger pump 2201 discharges high-pressure fluid, and the high-pressure fluid and the high-pressure fluid discharged by the first plunger pump 100 can be merged in the high-pressure pipeline; when the mover of the linear motor 210 moves to the other side, the second plunger pump 2201 inhales low-pressure fluid, and the second plunger pump 2202 discharges high-pressure fluid, and the high-pressure fluid and the high-pressure fluid discharged by the first plunger pump 100 can be merged in the high-pressure pipeline; this process is repeated, and the fluid pressure compensation structure can alternately discharge high-pressure fluid through the two second plunger pumps to achieve pulsation compensation for the high-pressure fluid discharged by the first plunger pump.

[0047] For example, Figure 1 As shown, taking the second plunger pump 2202 as an example, when the mover of the linear motor 210 moves in the direction approaching the second plunger pump 2202, the one-way valve of the second plunger pump 2202 opens, and high-pressure fluid is pumped into the pipeline connected to the output end of the first plunger pump 100; when the mover of the linear motor 210 moves in the direction away from the second plunger pump 2202, the one-way valve of the second plunger pump 2202 closes, the second plunger pump 2202 sucks in low-pressure fluid, and the high-pressure fluid in the output end (such as the output pipeline) of the second plunger pump 2202 is sealed by the one-way valve, and the cycle works in this way.

[0048] In the plunger pump system provided by the embodiment of the present disclosure, a linear motor is used to drive a double-acting second plunger pump for compensation. Through the reciprocating motion of the linear motor rotor, the second plunger pump located at one end of the linear motor is sucking liquid while the second plunger pump located at the other end of the linear motor is pressing liquid. The two second plunger pumps can work alternately, thereby improving the use efficiency of the linear motor and increasing the output flow of the second plunger pump.

[0049] For example, Figure 1 The fluid pressure compensation structure is schematically shown to include a linear motor and two second plunger pumps driven by the linear motor, but is not limited thereto. The fluid pressure compensation structure can include two linear motors and four second plunger pumps, or three linear motors and six second plunger pumps, and the output ends of all second plunger pumps are connected to the output end of the first plunger pump. The fluid pressure compensation structure provided in the embodiment of the present disclosure can be set according to the actual engineering requirements to set the number of linear motors and second plunger pumps.

[0050] For example, Figure 1 As shown, the linear motor 210 may further include a linear motor driver 400, which is electrically connected to the mover of the linear motor 210 and configured to control the mover of the linear motor 210 to perform high-speed linear reciprocating motion. Linear motors are easy to adjust and control. For example, by adjusting the voltage or frequency of the linear motor, the linear motor can have different speeds and electromagnetic thrusts. Thus, the linear motor is suitable for a variety of reciprocating motion scenarios.

[0051] For example, Figure 2 FIG. 1 is a schematic diagram of a fluid pressure compensation structure according to another example of an embodiment of the present disclosure. Figure 2 As shown, the fluid pressure compensation structure provided in this example is Figure 1 The difference of the fluid pressure compensation structure shown is that: in the fluid pressure compensation structure 200, the at least one linear motor 210 includes multiple linear motors 210, and the number of second plunger pumps 220 driven by at least one linear motor 210 among the multiple linear motors 210 is one.

[0052] For example, Figure 2 As shown, each linear motor 210 is a single-acting linear motor, and the mover of each linear motor 210 independently drives a second plunger pump 220. The fluid pressure compensation structure 200 includes at least two linear motors 210 and a second plunger pump 220 driven by the at least two linear motors 210, thereby achieving pressure pulsation compensation for the high-pressure fluid discharged by the first plunger pump. For example, the output ends of the second plunger pumps 220 driven by the at least two linear motors 210 are both connected to the output end of the first plunger pump. For example, the input ends of the second plunger pumps 220 driven by the at least two linear motors 210 can both be connected to the input end of the first plunger pump, or at least one can be connected to the input end of the first plunger pump, or neither can be connected.

[0053] For example, the fluid pressure compensation structure 200 may include a combination of 2-7 linear motors 210 , and the number of the second plunger pumps 220 is the same as the number of the linear motors 210 .

[0054] Of course, in the embodiment of the present disclosure, multiple linear motors can all be single-acting linear motors, or all be double-acting linear motors, or include some single-acting linear motors and some double-acting linear motors. The embodiment of the present disclosure does not limit this and can be set according to actual needs.

[0055] For example, Figure 1As shown, the plunger pump system further includes a controller 500 electrically connected to the linear motor 210. For example, the controller 500 is configured to adjust the speed of the linear motor 210 according to the rotational speed of the first plunger pump 100 so that the period of the pressure pulsation of the fluid output from the output end 221 of the second plunger pump 220 is equal to the period of the pressure pulsation of the fluid output from the output end 101 of the first plunger pump 100, and the phases of the two are opposite. The rotational speed of the first plunger pump 100 mentioned above includes the rotational speed of the crankshaft.

[0056] For example, the controller 500 can calculate a first pulsation period of the pressure pulsation of the fluid output by the first plunger pump 100 based on the rotational speed of the first plunger pump 100. The controller 500 controls the linear motor driver 400 based on the first pulsation period to adjust the speed of the linear motor 210, so that the fluid output by the second plunger pump 220 can have a second pulsation period that is the same as the first pulsation period, and the two pressure pulsations are in opposite phases. For example, the controller 500 can adjust the movement of the mover of the linear motor 210 by adjusting the speed of the linear motor 210, adjust the movement speed of the plunger in the second plunger pump 220, and achieve adjustment of the period and phase of the pressure pulsation of the fluid output by the second plunger pump 220.

[0057] The embodiment of the present disclosure collects the rotational speed of the first plunger pump (such as a multi-cylinder plunger pump) and adjusts the speed of the linear motor so that the output pressure pulsation period of the second plunger pump (such as a single-cylinder plunger pump) driven by the linear motor matches the output pressure pulsation period of the first plunger pump (such as a multi-cylinder plunger pump), thereby compensating for the output pressure pulsation of the first plunger pump.

[0058] For example, Figure 1 As shown, the plunger pump system further includes a speed acquisition unit 600, which is connected to the first plunger pump 100 and is configured to acquire the speed of the first plunger pump 100. For example, the speed acquisition unit 600 may include a speed sensor, an encoder, a photoelectric sensor, and the like.

[0059] For example, Figure 3 for Figure 1 The schematic diagram of the electrical connection between the controller and the speed acquisition unit is shown in FIG. Figure 1 and Figure 3 As shown, the controller 500 is electrically connected to the rotation speed acquisition unit 600 , and the rotation speed acquisition unit 600 transmits the acquired rotation speed data of the first plunger pump 100 to the controller 500 .

[0060] For example, Figure 4 for Figure 1 The controller shown is a schematic diagram of at least part of the process of adjusting the speed of the linear motor according to the speed of the first piston pump. Figure 1 and Figure 4As shown, the controller 500 includes a linear conversion unit 510 and a speed adjustment unit 520. For example, the linear conversion unit 510 is configured to perform a linear conversion calculation based on the rotational speed of the first plunger pump 100 to obtain a pulsation period of the fluid output by the first plunger pump 100, and the pulsation period is equal to the pulsation period of the fluid output by the fluid pressure compensation structure 200. The concept of "equal" in the embodiments of the present disclosure includes the meaning of approximately equal and completely equal. Approximately equal means that the ratio of the difference between the two to either of the two is no more than 10%.

[0061] Since the speed of the first plunger pump (such as a multi-cylinder plunger pump) in field operations can be variable, in order to adapt to various actual operating conditions, the unstable speed of the multi-cylinder plunger pump can be collected and linearly converted to calculate the changing pulsation period of the linear motor.

[0062] For example, the linear conversion unit 510 may be a module implemented by software, or may be a hardware circuit constructed to implement the corresponding function. The hardware circuit includes a conventional very large scale integration (VLSI) circuit or gate array and existing semiconductors such as logic chips, transistors, or other discrete components.

[0063] For example, a linear transformation calculation may include the following formula:

[0064] The second plunger pump movement period = (60×the first plunger pump reduction ratio) / (the first plunger pump speed×the first plunger pump cylinder number).

[0065] For example, Figure 1 As shown, the speed adjustment unit 520 is configured to calculate the preset speed of the linear motor 210 based on the pulsation period of the fluid, and the controller 500 adjusts the speed of the linear motor 210 according to the preset speed. For example, the controller 500 is configured to control the linear motor driver 400 to adjust the movement speed of the linear motor 210 to the above-mentioned preset speed.

[0066] For example, Figure 1 and Figure 4 As shown, the plunger pump system also includes a speed feedback unit 01. The speed feedback unit 01 can collect the speed of the linear motor and feed back the collected speed data of the linear motor to the controller 500. The controller 500 can compare the above-mentioned preset speed with the actual speed of the linear motor. If the difference between the two is large, the controller 500 can adjust at least one of the linear conversion unit and the speed adjustment unit to adjust the actual speed of the linear motor to be basically equal to the preset speed.

[0067] For example, Figure 1As shown, the plunger pump system further includes a pressure acquisition unit 700, which is connected to the first plunger pump 100 and is configured to acquire a pressure pulsation signal of the fluid output by the first plunger pump 100. For example, the pressure acquisition unit 700 may include a pressure sensor or a pressure transmitter to measure the fluid pressure.

[0068] For example, Figure 5 for Figure 1 The schematic diagram of the electrical connection between the controller and the pressure acquisition unit is shown in FIG. Figure 1 and Figure 5 As shown, the pressure acquisition unit 700 is electrically connected to the controller 500, and the controller 500 is configured to control the thrust of the linear motor 210 based on the pressure pulsation signal collected by the pressure acquisition unit 700. For example, the pressure acquisition unit 700 transmits the collected data of the pressure of the fluid output by the first plunger pump 100 to the controller 500.

[0069] For example, the controller 500 is configured to adjust the thrust and speed of the linear motor 210 according to the pressure of the fluid output by the first plunger pump 100, so that the pressure amplitude of the pressure pulsation of the fluid output from the output end of the second plunger pump 220 is equal to the pressure amplitude of the pressure pulsation of the fluid output from the output end of the first plunger pump 100, and the phases of the two are opposite.

[0070] The embodiment of the present disclosure collects the discharge pressure of the first plunger pump (such as a multi-cylinder plunger pump) and feeds it back to the controller. The controller controls the linear motor driver and then adjusts the thrust of the linear motor so that the second plunger pump forms a pulsation with the same effective value amplitude and opposite phase as the pressure pulsation of the fluid discharged by the first plunger pump.

[0071] The pressure of the fluid discharged by the first plunger pump may be determined by the load at the rear end connected to the output end of the first plunger pump.

[0072] The disclosed embodiment does not alter the pressure of the fluid discharged by a first plunger pump (e.g., a multi-cylinder plunger pump). Instead, the fluid pressure compensation structure compensates for pressure pulsations in the fluid discharged by the first plunger pump. The controller can adjust the thrust of the linear motor based on changes in the pressure of the fluid discharged by the first plunger pump to accommodate increases and decreases in the pressure of the fluid discharged by the first plunger pump, thereby effectively compensating for the pressure of the fluid discharged by the first plunger pump.

[0073] For example, the controller is configured to adjust the speed of the linear motor and / or adjust the thrust of the linear motor. For example, the controller can adjust both the speed of the linear motor and the thrust of the linear motor, with the speed being the primary adjustment.

[0074] For example, the controller in the embodiment of the present disclosure can be implemented by software so as to be executed by various types of processors, or it can be a hardware circuit built to implement the corresponding functions, and the hardware circuit includes conventional very large scale integration (VLSI) circuits or gate arrays and existing semiconductors such as logic chips, transistors, or other discrete components.

[0075] Figure 6 FIG. 1 is a structural block diagram of a fracturing device according to an embodiment of the present disclosure. Figure 6 As shown, the fracturing equipment includes the plunger pump system provided in the above embodiment. The fracturing equipment provided in the disclosed embodiment includes a fluid pressure compensation structure comprising a linear motor and a second plunger pump. The linear motor is compact, facilitating integration with the second plunger pump to achieve a compact design. The linear motor is also easily adjustable and controllable to compensate for pressure pulsations in the fluid output by the first plunger pump.

[0076] Another embodiment of the present disclosure provides a pressure pulsation compensation method applied to any of the above-mentioned plunger pump systems, the pressure pulsation compensation method including: adjusting the speed of the linear motor according to the rotational speed of the first plunger pump so that the period of the pressure pulsation of the fluid output from the output end of the second plunger pump is equal to the period of the pressure pulsation of the fluid output from the output end of the first plunger pump, and the two are in opposite phases; and / or, adjusting the thrust of the linear motor according to the pressure of the fluid output from the first plunger pump so that the pressure amplitude of the pressure pulsation of the fluid output from the output end of the second plunger pump is equal to the pressure amplitude of the pressure pulsation of the fluid output from the output end of the first plunger pump, and the two are in opposite phases.

[0077] For example, adjusting the speed of the linear motor according to the rotational speed of the first plunger pump includes: collecting the rotational speed of the first plunger pump; performing linear conversion calculation based on the rotational speed of the first plunger pump to obtain the pulsation period of the fluid output by the fluid pressure compensation structure; and calculating the preset speed of the linear motor based on the pulsation period of the fluid, and adjusting the rotational speed of the linear motor according to the preset speed.

[0078] For example, Figure 1 As shown, the speed acquisition unit 600 is connected to the first plunger pump 100 and is configured to acquire the speed of the first plunger pump 100. For example, the controller 500 can calculate a first pulsation period of the pressure pulsation of the fluid output by the first plunger pump 100 based on the speed of the first plunger pump 100. The controller 500 controls the linear motor driver 400 to adjust the speed of the linear motor 210 based on the first pulsation period, so that the fluid output by the second plunger pump 220 can have a second pulsation period that is the same as the first pulsation period, and the two pressure pulsations are in opposite phases.

[0079] For example, Figure 1As shown, the linear conversion unit 510 is configured to perform a linear conversion calculation based on the rotational speed of the first plunger pump 100 to obtain a pulsation period of the fluid output by the first plunger pump 100. This pulsation period is equal to the pulsation period of the fluid output by the fluid pressure compensation structure 200. For example, the speed adjustment unit 520 is configured to calculate a preset speed of the linear motor 210 based on the pulsation period of the fluid, and the controller 500 adjusts the speed of the linear motor 210 based on the preset speed. For example, the controller 500 is configured to control the linear motor driver 400 to adjust the motion speed of the linear motor 210 to the preset speed.

[0080] For example, adjusting the thrust of the linear motor according to the pressure of the fluid output by the first plunger pump includes: collecting a pressure pulsation signal of the fluid output by the first plunger pump; and controlling the thrust of the linear motor according to the pressure pulsation signal.

[0081] For example, Figure 1 As shown, the pressure acquisition unit 700 is connected to the first plunger pump 100 and is configured to collect the pressure pulsation signal of the fluid output by the first plunger pump 100. For example, the pressure acquisition unit 700 is electrically connected to the controller 500, and the controller 500 is configured to control the thrust of the linear motor 210 based on the pressure pulsation signal collected by the pressure acquisition unit 700. For example, the pressure acquisition unit 700 transmits the collected data on the pressure of the fluid output by the first plunger pump 100 to the controller 500.

[0082] The pressure pulsation compensation method provided by the embodiment of the present disclosure and applied to any of the above-mentioned plunger pump systems can adjust at least one of the phase, period and pressure amplitude of the fluid output by the fluid pressure compensation structure according to the rotational speed of the first plunger pump and at least one of its output fluids, thereby compensating for the pressure pulsation of the fluid output by the first plunger pump.

[0083] There are a few points to note:

[0084] (1) The drawings of the embodiments of the present disclosure only involve structures related to the embodiments of the present disclosure, and other structures can refer to general designs.

[0085] (2) In the absence of conflict, features in the same embodiment and different embodiments of the present disclosure may be combined with each other.

[0086] The foregoing description is merely an exemplary embodiment of the present disclosure and is not intended to limit the scope of protection of the present disclosure. The scope of protection of the present disclosure is determined by the appended claims.

Claims

1. A plunger pump system comprising: First plunger pump; a fluid pressure compensation structure configured to compensate for pressure pulsation of the fluid output from the output end of the first plunger pump; Wherein, the fluid pressure compensation structure includes at least one linear motor and a second plunger pump driven by the at least one linear motor, and the output end of the second plunger pump is connected to the output end of the first plunger pump; The plunger pump system further comprises: a controller electrically connected to the linear motor; wherein the controller is configured to adjust the speed of the linear motor according to the rotational speed of the first plunger pump so that the period of the pressure pulsation of the fluid output from the output end of the second plunger pump is equal to the period of the pressure pulsation of the fluid output from the output end of the first plunger pump, and the phases of the two are opposite; and / or, The controller is configured to adjust the thrust of the linear motor according to the pressure of the fluid output by the first plunger pump, so that the pressure pulsation of the fluid output by the output end of the second plunger pump is equal to the pressure amplitude of the pressure pulsation of the fluid output by the output end of the first plunger pump, and the phases of the two are opposite; The first plunger pump includes a multi-cylinder plunger pump, the second plunger pump includes a single-cylinder plunger pump, and an input end of the second plunger pump is not connected to an input end of the first plunger pump.

2. The plunger pump system according to claim 1, wherein: The number of the second plunger pumps driven by each linear motor is two, and the two ends of the mover of the linear motor are respectively connected to and drive two second plunger pumps. The linear motor and the two second plunger pumps are arranged in a straight line, and the mover of the linear motor is configured to move back and forth linearly between the two second plunger pumps.

3. The plunger pump system according to claim 1, wherein: The at least one linear motor includes a plurality of linear motors, and the number of the second plunger pump driven by at least one linear motor among the plurality of linear motors is one.

4. The plunger pump system according to claim 1, further comprising: a rotation speed collecting unit connected to the first plunger pump and configured to collect the rotation speed of the first plunger pump; and / or, The pressure collecting unit is connected to the first plunger pump and is configured to collect a pressure pulsation signal of the fluid output by the first plunger pump.

5. The plunger pump system according to claim 4, wherein: The controller is electrically connected to the speed acquisition unit, and the controller includes a linear conversion unit and a speed adjustment unit. The linear conversion unit is configured to perform linear conversion calculation based on the speed of the first plunger pump to obtain the pulsation period of the fluid output by the fluid pressure compensation structure; the speed adjustment unit is configured to calculate the preset speed of the linear motor based on the pulsation period of the fluid, and the controller adjusts the speed of the linear motor according to the preset speed.

6. The plunger pump system according to claim 4, wherein: The pressure collecting unit is electrically connected to the controller, and the controller is configured to control the thrust of the linear motor according to the pressure pulsation signal collected by the pressure collecting unit.

7. A fracturing device comprising the plunger pump system according to any one of claims 1 to 6.

8. A pressure pulsation compensation method applied to the plunger pump system according to claim 1, comprising: adjusting the speed of the linear motor according to the rotational speed of the first plunger pump so that the period of the pressure pulsation of the fluid output from the output end of the second plunger pump is equal to the period of the pressure pulsation of the fluid output from the output end of the first plunger pump, and the phases of the two are opposite; and / or, The thrust of the linear motor is adjusted according to the pressure of the fluid output by the first plunger pump so that the pressure amplitude of the pressure pulsation of the fluid output by the output end of the second plunger pump is equal to the pressure amplitude of the pressure pulsation of the fluid output by the output end of the first plunger pump, and the phases of the two are opposite.

9. The pressure pulsation compensation method according to claim 8, wherein: Adjusting the speed of the linear motor according to the rotation speed of the first plunger pump includes: collecting the rotational speed of the first plunger pump; performing linear conversion calculation based on the rotation speed of the first plunger pump to obtain the pulsation period of the fluid output by the fluid pressure compensation structure; and The preset speed of the linear motor is calculated according to the pulsation period of the fluid, and the speed of the linear motor is adjusted according to the preset speed.

10. The pressure pulsation compensation method according to claim 8, wherein: Adjusting the thrust of the linear motor according to the pressure of the fluid output by the first plunger pump includes: collecting a pressure pulsation signal of the fluid output by the first plunger pump; and The thrust of the linear motor is controlled according to the pressure pulsation signal.

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