A sealed double-arm gas-liquid displacement wave energy power generation device and a booster pump operation control method

Abstract

This invention relates to the field of energy conversion technology, and discloses a closed-loop double-arm gas-liquid displacement wave energy power generation device and a booster pump operation control method. The device includes a first and second liquid arm rigidly arranged at a fixed angle, a gas phase balance circuit, an integrated bottom manifold valve box, and an energy conversion module. The gas phase spaces at the top of the two liquid arms are connected through a bidirectional gas phase balance circuit located above the highest working liquid level, preventing airlock. Four one-way valves in the integrated bottom manifold valve box open alternately according to the pressure difference direction at the two arm ports, ensuring that the working fluid flows through the turbine in the same direction during both half-cycles of the roll, driving the permanent magnet generator to generate electricity and power the booster pump. The device can also be equipped with bypass pressure equalization, low-pressure relief, fluid replenishment to prevent cavitation, mooring, self-righting, and limit structures. This invention can achieve low-loss, unidirectional energy extraction of the closed working fluid while avoiding impedance mismatch in the high-pressure hydraulic link, making it suitable for auxiliary pressurization of offshore pipelines and distributed energy supply.

Description

Technical Field

[0001] This invention relates to the field of energy conversion, and in particular to a closed double-arm gas-liquid displacement wave energy power generation device and a booster pump operation control method. Background Technology

[0002] With the development of science and technology, energy conversion technology is constantly improving.

[0003] Currently, long-distance pipelines are commonly used in scenarios such as marine oil and gas transportation, seawater desalination intake and discharge, island water supply, offshore aquaculture, and offshore platform replenishment. When fluids are transported within these pipelines, they are affected by frictional resistance along the pipeline, resistance from local components, and elevation differences, causing the pressure to gradually decrease. This typically necessitates the use of booster pumps. When booster pumps are located far from shore or platforms, relying on long-distance submarine cables, fuel-powered generator sets, or frequent battery replacements increases construction costs, maintenance workload, and the risk of failure.

[0004] Wave energy is characterized by its availability on-site and its energy distribution being similar to that of offshore pipelines. However, there is a lack of technologies that can operate at sea and effectively convert wave energy into electricity. Summary of the Invention

[0005] This invention provides a closed-loop double-arm gas-liquid displacement wave energy power generation device and a booster pump operation control method to solve the deficiency in related technologies of lacking a way to work at sea and effectively convert wave energy into electrical energy, and to work at sea and effectively convert wave energy into electrical energy.

[0006] In a first aspect, the present invention provides a closed-loop double-arm gas-liquid displacement wave energy generation device, comprising: The wave capture body includes a first liquid arm and a second liquid arm located on both sides of a preset roll axis and arranged in a bifurcated symmetrical manner; wherein, the first liquid arm and the second liquid arm are closed buoyancy box-shaped cavities that generate roll under the action of ocean waves, and the interior includes a top gas phase space, a working liquid cavity and a working liquid. A gas phase balance circuit is formed by connecting the top gas phase space of the first liquid arm and the second liquid arm through a pipeline. The circuit is positioned above the highest working liquid level of the first liquid arm and the second liquid arm to balance the gas pressure of the first liquid arm and the second liquid arm and prevent gas lock. An integrated bottom manifold valve box is installed in the lower region of the first liquid arm and the second liquid arm, and a pipe connects the bottom end of the first liquid arm and the bottom end of the second liquid arm; wherein, the working fluid is affected by ocean waves and flows back and forth between the first liquid arm, the integrated bottom manifold valve box and the second liquid arm; The energy conversion module connects the integrated bottom manifold valve box and the booster pump, and is used to convert the mechanical energy of the working fluid into electrical energy through the integrated bottom manifold valve box to drive the booster pump.

[0007] Optionally, the integrated bottom manifold valve box is provided with the following inside; The common cavity of the first arm is located below the lowest working liquid level in the first liquid arm. It is connected to the bottom end of the first liquid arm by a pipe, equipped with an anti-vortex guide cover, and remains submerged at the maximum design roll angle. The common cavity of the second arm is located below the lowest working liquid level in the second liquid arm. It is connected to the bottom end of the second liquid arm by a pipe, equipped with an anti-vortex guide cover, and remains submerged at the maximum design roll angle. A full-wave liquid flow rectifier bridge is located between the common cavity of the first arm and the common cavity of the second arm; Under the action of ocean waves, an alternating pressure difference is formed between the first arm common cavity and the second arm common cavity, and the working fluid flows back and forth between the first arm common cavity, the full-wave liquid flow rectification bridge and the second arm common cavity.

[0008] Optionally, the full-wave liquid flow rectifier bridge includes: The first check valve has its inlet end connected to the common cavity of the first arm. The second check valve has its inlet end connected to the common chamber of the second arm. The turbine inlet manifold has its input end connected to the outlet end of the first check valve and the outlet end of the second check valve. The water turbine's input end is connected to the output end of the water turbine's inlet manifold. The turbine outlet diversion chamber has its input end connected to the turbine's output end. The third check valve has its inlet end connected to the output end of the turbine outlet diversion chamber and its outlet end connected to the common chamber of the first arm. The fourth check valve has its inlet end connected to the output end of the turbine outlet diversion chamber, and its outlet end connected to the common chamber of the second arm.

[0009] Optionally, when the pressure in the first arm common cavity is higher than the pressure in the second arm common cavity, the working fluid flows along the first arm common cavity, the first check valve, the turbine inlet manifold, the turbine, the turbine outlet diversion cavity, and the fourth check valve to the second arm common cavity; When the pressure in the second arm common cavity is higher than the pressure in the first arm common cavity, the working fluid flows along the second arm common cavity, the second check valve, the turbine inlet manifold, the turbine, the turbine outlet diversion cavity, and the third check valve to the first arm common cavity.

[0010] Optionally, the gas-phase balance loop includes: A gas phase balance connecting pipe connects the top gas phase spaces of the first liquid arm and the second liquid arm at both ends; An adjustable flow element is installed in the middle section of the gas phase balance connecting pipe to change the gas reciprocating flow damping, thereby adjusting the working fluid response amplitude and phase. A two-way differential pressure bypass valve is connected in parallel to both ends of the adjustable flow element. It is used to open when the gas phase pressure difference between the two arms exceeds the set value, so as to prevent the tuning damping from becoming a gas lock. A variable volume gas chamber is provided on the gas phase balance connecting pipe to change the gas phase equivalent compliance; A gas-liquid separation chamber or a vertical liquid-catching section is provided at both ends of the gas phase balance connecting pipe to prevent the working fluid from entering the gas path during large swaying.

[0011] Optionally, the energy conversion module includes: A magnetic coupler is installed on both sides of a static sealing partition, and the inner rotor of the magnetic coupler is connected to the wet rotor of the water turbine. A permanent magnet generator is located in an independent dry compartment and is connected to the outer rotor of the magnetic coupler. The drive module is connected to the permanent magnet generator and transmits the electrical energy output by the permanent magnet generator to the pipeline booster pump to drive the booster pump to work.

[0012] Optionally, the first liquid arm and the second liquid arm are arranged symmetrically in a V-shape or Y-shape on both sides of the preset rocking shaft.

[0013] Optionally, the closed-loop double-arm gas-liquid displacement wave energy generation device further includes: The counterweight chamber is located at the bottom of the closed double-arm gas-liquid displacement wave energy power generation device, and is used to make the center of gravity of the closed double-arm gas-liquid displacement wave energy power generation device lower than the center of buoyancy, thereby forming a passive self-righting torque. The mooring assembly, located below the counterweight compartment, includes a universal joint, a single-point mooring adapter, a tensioning cable, or a flexible anchor chain, which enables the enclosed double-arm gas-liquid displacement wave energy generation device to adapt to the wave roll while limiting drift, yaw, and collision with pipelines. A damping fin, located below the mooring assembly and connected to the mooring assembly, is used to reduce high-frequency oscillation. An anchor, located below the mooring assembly, connects to the mooring assembly; A limiting cable or limiting block is disposed outside the first and second liquid arms to limit the maximum roll angle.

[0014] Optionally, the closed-loop double-arm gas-liquid displacement wave energy generation device further includes; A bypass pressure equalization branch is connected to the common cavity of the first arm and the common cavity of the second arm. It is used to open during storms, maintenance, startup or shutdown, so that the working fluid in the first liquid arm and the second liquid arm bypasses the turbine and quickly equalizes the pressure. A low-pressure relief valve and a buffer chamber are provided. The low-pressure relief valve is connected to the integrated bottom manifold box and the buffer chamber to suppress instantaneous negative pressure and cavitation.

[0015] Secondly, the present invention provides a booster pump operation control method, applied to the closed double-arm gas-liquid displacement wave energy power generation device described in the first aspect or any corresponding embodiment above, the method comprising: Monitor the target parameter values ​​and wave energy-related parameter values ​​of the booster delivery pipeline; wherein, the booster delivery pipeline is the pipeline where the booster pump is located, the target parameter is the downstream pressure or the pressure difference between the upstream and downstream of the booster delivery pipeline, and the wave energy-related parameter value is at least one of the pressure difference between the two ends of the integrated bottom manifold valve box, the turbine speed, and the roll angle; If it is determined that the booster pump has sufficient power supply based on the wave energy related parameter values, and it is determined that the target parameter value is lower than the set value, then the speed of the booster pump is controlled to be within the set high-speed range. If the power supply of the booster pump is insufficient based on the wave energy-related parameter values, the speed of the booster pump is controlled to be within a set low speed range or to enter an intermittent operation mode.

[0016] The closed-loop double-arm gas-liquid displacement wave energy generation device and booster pump operation control method provided by this invention address the following problems and achieve the following beneficial effects compared to related technologies: (1) When liquid transfer occurs between the closed double arms in the related technology, the gas phase pressure difference may form an airlock. The present invention sets up a bidirectional gas phase balance circuit above the highest working liquid level, so that the gas on the receiving side enters the supply side in reverse, and the gas phase pressure difference is limited by differential pressure bypass.

[0017] (2) The alternating roll direction in related technologies leads to alternating liquid flow direction, making it difficult for ordinary water turbines to rotate continuously in the same direction. This invention uses four low opening and closing pressure differential check valves to form a full-wave liquid flow rectification bridge. The conduction combination is automatically switched according to the pressure differential direction of the two arms. A pair of valves is opened under the two pressure differential directions respectively, so that the inlet and outlet directions of the water turbine 130 remain unchanged. The water turbine 130 does not need to repeatedly change direction, thus realizing full-wave unidirectional energy extraction.

[0018] (3) The available head in related technologies is limited, and the local resistance caused by ordinary cross pipes and valves is too large. The present invention integrates the two arm ports, four valves, short flow channels, turbine volute, bypass and maintenance structure into a bottom manifold valve box, shortens the flow channel and adopts rounded corner transition. Specifically, the integrated manifold valve box integrates the common port, four valves, short flow channels and turbine 130, reduces long pipes, bends and cross connections, and reduces internal losses under limited head.

[0019] (4) The low head and high flow energy in related technologies are not matched with the impedance of the high pressure hydraulic energy storage link. The present invention adopts a smooth electrical link of low head turbine 130, permanent magnet generator 220, rectifier, DC bus 250 and supercapacitor 240 / battery, so as not to forcibly convert low pressure and high flow energy into 100 bar hydraulic energy and avoid energy impedance mismatch.

[0020] (5) The dynamic adjustment of the angle of the large double arms in the related technology is complex and has a high risk of fatigue in the marine environment. The double arms of the present invention adopt a rigid fixed angle, and the response is adjusted by the liquid filling rate, the counterweight position during the commissioning period, the gas phase damping and the variable volume air chamber 111.

[0021] (6) In related technologies, float drift, yaw, or lack of reaction force can weaken roll energy harvesting and affect the safety of subsea pipelines. The present invention sets up single-point mooring, universal joint support, or tensioned mooring, which allows the device to roll but limits drift, and decouples the mooring load from the pipeline load.

[0022] (7) In related technologies, overcurrent, cavitation, overpressure and excessive roll may occur under storm conditions. This invention is equipped with passive priority bypass pressure equalization, pressure relief, low pressure liquid replenishment, self-righting counterweight, damping fin 152 and limiting structure.

[0023] This invention also reduces the risk of sealing maintenance, isolates the working fluid 105 from seawater, preferably uses magnetic coupling drive, and reduces the need for through-type rotary shaft seals.

[0024] The device structure of this invention is adjustable but not overly complex. The angle between the two arms is fixed and matched by the liquid filling rate, the counterweight during the commissioning period, and the gas phase damping, thus avoiding large dynamic articulation mechanisms.

[0025] The device of this invention possesses maritime survivability. Mooring decoupling, counterweight self-righting, damping fin 152, limiting, bypass, and mechanical pressure relief work together to cope with extreme sea conditions.

[0026] The device of this invention is adapted to the actual needs of pipelines. Based on the pipeline pressure difference and available energy, the pump speed can be adjusted, and it can operate independently or be integrated into a hybrid energy supply system. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in this invention or related technologies, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of the structure of a closed double-arm gas-liquid displacement wave energy power generation device provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of a closed double-arm gas-liquid reverse displacement and anti-airlock structure provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of an integrated bottom manifold valve box provided in an embodiment of the present invention; Figure 4 A schematic diagram of the main channel working state of a full-wave liquid flow rectifier bridge provided in an embodiment of the present invention; Figure 5 A schematic diagram of the main channel working state of another full-wave liquid flow rectifier bridge provided in an embodiment of the present invention; Figure 6 A schematic diagram of a power conversion, electrical smoothing, and pipeline pressure control link provided in an embodiment of the present invention; Figure 7 This is a schematic diagram of a bypass depressurization, mooring, self-righting and storm protection structure provided in an embodiment of the present invention; Figure 8 A flowchart of a booster pump operation control method provided in an embodiment of the present invention.

[0029] Explanation of reference numerals in the attached figures: 101-First liquid arm; 102-Second liquid arm; 105-Working fluid; 106-Top gas phase space; 110-Gas phase balance connecting pipe; 111-Variable volume gas chamber; 112-Adjustable flow element; 114-Two-way differential pressure bypass valve; 120-Integrated bottom manifold valve box; 121-First check valve; 122-Second check valve; 123-Third check valve; 124-Fourth check valve; 125-Cover plate; 126-First arm common chamber; 127-Second arm common chamber; 128-Turbine inlet manifold; 129-Turbine outlet diversion chamber; 130-Turbine; 132-Magnetic coupler; 140-Bypass manifold Pressure valve; 141-Pressure relief valve; 142-Buffer chamber; 143-Low-pressure replenishment chamber; 144-Filter; 150-Counterweight chamber; 151-Limiting cable; 152-Damping fin; 160-Mooring assembly; 162-Anchor; 181-Tilt sensor; 220-Permanent magnet generator; 230-Rectifier and voltage regulator module; 240-Supercapacitor; 250-DC bus; 260-Motor driver; 270-Controller; 280-Unloading load; 300-Flexible underwater cable; 400-Boost pump; 401-Boost pump motor; 500-Transportation pipeline; 501-Upstream pressure sensor; 502-Downstream pressure sensor. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0031] Wave energy harvesting devices in related technologies mostly utilize the heave, swaying, or articulated components of floating bodies to drive mechanical transmissions, hydraulic cylinders, or linear generators. These technologies cannot solve problems such as alternating wave input directions, output pulsation, seawater corrosion, and survival in extreme sea conditions. Related technologies utilize the sloshing of liquid within a sealed container to harvest energy, isolating the working fluid from seawater. However, ordinary sealed double-chamber or double-arm structures have two prominent problems: First, when the liquid transfers from one side to the other, the gas phase space on the supply side expands while the gas phase space on the receiving side compresses. If the gas cannot be synchronously replaced in the opposite direction, airlock will occur, quickly offsetting the liquid level difference. Second, the reciprocating flow direction of the liquid changes with the roll direction. If directly connected to a water turbine, the turbine will repeatedly change direction or stop, making stable power generation difficult.

[0032] Furthermore, the energy generated by the liquid level difference within the dual arms in related technologies is mainly characterized by low pressure, high flow rate, and periodic changes, making it unsuitable for directly driving 100-bar hydraulic pumps and high-pressure hydraulic accumulators. If long pipelines, multiple bends, and ordinary high-pressure-differential-pressure-drop check valves are used under limited head conditions, local losses may exceed the available pressure differential. Therefore, a wave energy harvesting device is needed that structurally addresses issues such as airlock, liquid flow reversal, low head loss, smooth output, mooring self-righting, and storm protection.

[0033] The following is combined with Figures 1-7 The present invention describes a closed-loop double-arm gas-liquid displacement wave energy generation device.

[0034] like Figure 1 As shown, this embodiment proposes a first type of closed-loop double-arm gas-liquid displacement wave energy generation device, which includes: The wave capture body includes a first liquid arm 101 and a second liquid arm 102 located on both sides of a preset roll axis and arranged in a bifurcated symmetrical manner; wherein, the first liquid arm 101 and the second liquid arm 102 are closed buoyancy box-shaped cavities that generate roll under the action of ocean waves, and the interior includes a top gas phase space 106, a working liquid cavity and a working liquid 105. A gas phase balance circuit is provided, with a pipeline connecting the top gas phase space 106 of the first liquid arm 101 and the second liquid arm 102. The circuit is positioned above the highest working liquid level of the first liquid arm 101 and the second liquid arm 102, and is used to balance the gas pressure of the first liquid arm 101 and the second liquid arm 102 and prevent gas lock. An integrated bottom manifold valve box 120 is arranged in the lower region of the first liquid arm 101 and the second liquid arm 102, and a pipe connects the bottom end of the first liquid arm 101 and the bottom end of the second liquid arm 102; wherein, the working fluid 105 is subjected to ocean waves and flows back and forth between the first liquid arm 101, the integrated bottom manifold valve box 120 and the second liquid arm 102. The energy conversion module connects the integrated bottom manifold valve box 120 and the booster pump 400. It is used to convert the mechanical energy of the working fluid 105 into electrical energy through the integrated bottom manifold valve box 120 and drive the booster pump 400 to work.

[0035] The gas-phase equilibrium loop includes: The gas phase balance connecting pipe 110 is connected at both ends to the top gas phase space 106 of the first liquid arm 101 and the second liquid arm 102; An adjustable flow element 112 is installed in the middle section of the gas phase balance connecting pipe 110 to change the gas reciprocating flow damping, thereby adjusting the response amplitude and phase of the working fluid 105. A two-way differential pressure bypass valve 114 is connected in parallel to both ends of the adjustable flow element 112. It is used to open when the gas phase pressure difference between the two arms exceeds the set value, so as to prevent the tuning damping from becoming a gas lock. A variable volume gas chamber 111 is provided on the gas phase balance connecting pipe 110 to change the gas phase equivalent compliance; The gas-liquid separation chamber or vertical liquid capture section is set at both ends of the gas phase balance connecting pipe 110 to prevent the working fluid 105 from entering the gas path during large swaying.

[0036] Optionally, in other closed double-arm gas-liquid displacement wave energy generation devices proposed in this embodiment, the gas phase balance circuit includes a bidirectional connecting pipe and an adjustable flow element 112 connected in parallel or in series with it, and a bidirectional differential pressure bypass valve 114 is provided to open when the gas phase pressure difference exceeds a threshold.

[0037] Specifically, the wave capture device body includes a first liquid arm 101 and a second liquid arm 102 located on both sides of the rocker shaft and rigidly connected. Each liquid arm has a closed housing, a working liquid chamber, and a top gas phase space 106. The bottom ends of the two liquid arms are connected to an integrated bottom manifold valve box 120. The top gas phase spaces 106 of the two liquid arms are connected through a gas phase balance loop located above the highest working liquid level.

[0038] The waves cause the external buoyancy and inertial load of the two arms to change alternately, causing the device to roll. The height of the liquid column and the inertial pressure of the working fluid 105 inside the two arms change accordingly, forming a driving pressure difference that alternates between the bottom ends of the two liquid arms.

[0039] Optionally, the first liquid arm 101 and the second liquid arm 102 are arranged symmetrically in a V-shape or Y-shape on both sides of a preset rocking axis.

[0040] Specifically, the first liquid arm 101 and the second liquid arm 102 are preferably arranged symmetrically in a V-shape or Y-shape, and the rigid fixed included angle is preferably 80° to 120°, more preferably 85° to 100°. The two liquid arms can be cylindrical, elliptical, or box-shaped cavities with rounded corners, and are equipped with an external buoyancy shell so that the center of gravity of the device is located below the center of buoyancy. The included angle of the two arms remains unchanged during operation, avoiding large underwater hinges and actuators.

[0041] The working fluid 105 can be made of fresh water, antifreeze solution, low-viscosity environmentally friendly hydraulic fluid, or water-based liquid with added corrosion inhibitors; the top gas phase can be air or nitrogen. The filling rate of the working fluid 105 is preferably 40% to 65% of the effective cavity volume of the two arms.

[0042] The integrated bottom manifold valve box 120 is equipped with the following: The first arm common cavity 126 is located below the lowest working liquid level in the first liquid arm 101. It is connected to the bottom end of the first liquid arm 101 by a pipe, equipped with an anti-vortex guide cover, and kept submerged at the maximum design roll angle. The second arm common cavity 127 is located below the lowest working liquid level in the second liquid arm 102. It is connected to the bottom end of the second liquid arm 102 by a pipe, equipped with an anti-vortex guide cover, and kept submerged at the maximum design roll angle. The full-wave liquid flow rectifier bridge is located between the first arm common cavity 126 and the second arm common cavity 127; Under the action of ocean waves, an alternating pressure difference is formed between the first arm common cavity 126 and the second arm common cavity 127, and the working fluid 105 flows back and forth between the first arm common cavity 126, the full-wave liquid flow rectifier bridge and the second arm common cavity 127.

[0043] The full-wave liquid flow rectifier bridge includes: The first check valve 121 has its inlet end connected to the common cavity 126 of the first arm. The second check valve 122 has its inlet end connected to the common cavity 127 of the second arm. The turbine inlet manifold 128 has its input end connected to the outlet end of the first check valve 121 and the outlet end of the second check valve 122. The input end of the water turbine 130 is connected to the output end of the water turbine inlet manifold 128; The turbine outlet diversion chamber 129 is connected to the output end of the turbine 130 at its input end. The third check valve 123 has its inlet end connected to the output end of the turbine outlet diversion chamber 129 and its outlet end connected to the first arm common chamber 126. The fourth check valve 124 has its inlet end connected to the output end of the turbine outlet diversion chamber 129, and its outlet end connected to the second arm common chamber 127.

[0044] When the pressure in the first arm common cavity 126 is higher than the pressure in the second arm common cavity 127, the working fluid 105 flows along the first arm common cavity 126, the first check valve 121, the turbine inlet manifold 128, the turbine 130, the turbine outlet diversion cavity 129 and the fourth check valve 124 to the second arm common cavity 127. When the pressure in the second arm common cavity 127 is higher than the pressure in the first arm common cavity 126, the working fluid 105 flows along the second arm common cavity 127, the second check valve 122, the turbine inlet manifold 128, the turbine 130, the turbine outlet diversion cavity 129 and the third check valve 123 to the first arm common cavity 126.

[0045] like Figure 2The schematic diagram of the closed double-arm gas-liquid reverse displacement and anti-airlock structure shows that the lower parts of the two liquid arms are not directly connected by an uncontrolled large channel, but are connected to the integrated bottom manifold valve box 120 through the common cavity 126 of the first arm and the common liquid cavity of the second arm, respectively. Both the common liquid cavities of the first and second arms are arranged below the lowest operating liquid level and are equipped with anti-vortex guide hoods or porous rectifier hoods to avoid the intake of gas and the formation of strong vortices.

[0046] Specifically, under the action of waves, the first liquid arm 101 and the second liquid arm 102 experience alternating driving pressure differences between their common cavities 126 and 127. Let the instantaneous driving pressure difference between the two liquid common cavities be Δ. p d Its main components are the hydrostatic pressure difference generated by the height difference of the liquid column and the inertial pressure difference generated by the rolling acceleration. To ensure startup and continuous energy harvesting, the Δ under the design conditions should be... p d The pressure difference is greater than the sum of the opening and closing pressure difference of the four valves, the local losses in the flow channel, and the minimum starting pressure difference of the turbine 130. Ineffective losses are reduced by using large-diameter valves, short flow channels, and a low-resistance turbine 130.

[0047] The gas phase spaces at the top of the first liquid arm 101 and the second liquid arm 102 are connected by a bidirectional gas phase balance connecting pipe 110. The gas phase balance connecting pipe 110 is located above the highest working liquid level throughout its length, and gas-liquid separation chambers or vertical liquid capture sections can be set at both ends to prevent the working liquid 105 from entering the gas path during large swaying.

[0048] When the working fluid 105 flows from the first liquid arm 101 to the second liquid arm 102, the compressed gas in the second liquid arm 102 enters the first liquid arm 101 in the reverse direction through the gas phase balance connecting pipe 110; when the working fluid 105 flows from the second liquid arm 102 to the first liquid arm 101, the gas displacement direction is reversed. Therefore, the liquid transfer between the common chambers of the two liquid arms will not create a continuous negative pressure on the supply side, nor a continuous positive pressure on the receiving side.

[0049] Specifically, the gas phase balance circuit may include an adjustable flow element 112, a variable volume gas chamber 111, and a bidirectional differential pressure bypass valve 114. The adjustable flow element 112 is used to change the reciprocating flow damping of the gas to adjust the response amplitude and phase of the working fluid; the variable volume gas chamber 111 is used to change the gas phase equivalent compliance; the bidirectional differential pressure bypass valve 114 is connected in parallel with the throttling element 112 and automatically opens when the gas phase pressure difference between the two arms exceeds a set value to prevent the tuning damping from evolving into a gas lock. The initial gas pressure is mainly used to maintain the seal and adapt to temperature changes, and simply increasing the common gas pressure is not used as the sole tuning method.

[0050] like Figure 3As shown, the integrated bottom manifold valve box 120 is located in the low-position area where the two liquid arms intersect, and adopts a detachable cast shell, welded shell, or machined module. The valve box forms a first arm common cavity 126, a second arm common cavity 127, a turbine inlet manifold cavity 128, a turbine outlet branch cavity 129, and four short branches, and integrates a first check valve 121, a second check valve 122, a third check valve 123, a fourth check valve 124, and a low-head turbine 130. The low-head turbine 130 is connected in series between the turbine inlet manifold cavity 128 and the turbine outlet branch cavity 129. The working fluid 105 enters the turbine 130 from the inlet manifold cavity 128 to perform work, and then enters the outlet branch cavity 129. Except for the bypass equalization branch that is opened during storms or maintenance conditions, there is no normally open straight-through flow channel bypassing the turbine 130 between the two.

[0051] The first check valve 121 connects to the turbine inlet manifold 128 via the first arm common chamber 126; the second check valve 122 connects to the turbine inlet manifold 128 via the second arm common chamber 127; the third check valve 123 connects to the first arm common chamber 126 via the turbine outlet branch chamber 129; and the fourth check valve 124 connects to the second arm common chamber 127 via the turbine outlet branch chamber 129. These four check valves, together with the low-head turbine 130 connected in series between the inlet manifold 128 and the outlet branch chamber 129, constitute a liquid full-wave rectification energy harvesting circuit. Optionally, the four check valves, the low-head turbine 130, and the connecting flow channels are integrated into the same detachable housing.

[0052] like Figure 4 and Figure 5 As shown, the central vertical solid line represents the actual main flow channel from the turbine inlet manifold 128 through the low-head turbine 130 to the turbine outlet branch channel 129. The arrows set beside the main flow channel and each branch only indicate the flow direction of the working fluid under the current operating conditions and do not indicate additional pipelines. Figure 5 When the pressure in the first arm common cavity 126 is higher than that in the second arm common cavity 127, the first check valve 121 and the fourth check valve 124 open, and the working fluid 105 flows sequentially along the first arm common cavity 126, the first check valve 121, the turbine inlet manifold 128, the turbine 130, the turbine outlet diversion cavity 129 and the fourth check valve 124 to the second arm common cavity 127. Figure 5When the pressure in the second arm common cavity 127 is higher than that in the first arm common cavity 126, the second check valve 122 and the third check valve 123 open, and the working fluid 105 flows sequentially along the second arm common cavity 127, the second check valve 122, the turbine inlet manifold 128, the turbine 130, the turbine outlet diversion cavity 129, and the third check valve 123 to the first arm common cavity 126. In both operating conditions, the working fluid 105 flows from the inlet manifold 128 through the turbine 130 to the outlet diversion cavity 129; the turbine 130 does not need to reverse its direction.

[0053] Among them, the one-way valve is preferably a large-diameter flap valve, disc valve, or flexible duckbill valve with low opening and closing pressure differential. The connecting flow channels adopt rounded transitions and are symmetrically arranged with respect to the turbine 130. That is, each branch is preferably symmetrically arranged with rounded transitions, and sharp angles, sudden expansions, and unnecessary cross pipes are avoided inside the valve box. The valve components and turbine 130 can adopt drawer-type or cylindrical replaceable components, so that the main body of the double arms does not need to be disassembled during maintenance.

[0054] The low-head turbine 130 can be an axial-flow, through-flow, or cross-flow turbine, or a custom runner suitable for low pressure differential and high flow rate. Turbine 130 is designed for unidirectional flow reception, eliminating the need for frequent reversal. The flow area of ​​the guide vanes, diffuser section, and runner blades is determined based on the target pressure differential and flow rate, allowing for variable speed operation within the wave cycle.

[0055] The closed-loop double-arm gas-liquid displacement wave energy generation device proposed in this embodiment includes a wave capture body, a gas phase balance circuit, an integrated bottom manifold valve box 120, and an energy conversion module. The first liquid arm 101 and the second liquid arm 102 in the wave capture body are subjected to ocean waves. The working fluid 105 in the first liquid arm 101 and the second liquid arm 102 flows back and forth between the first liquid arm 101, the integrated bottom manifold valve box 120, and the second liquid arm 102, driving the energy conversion module to generate electricity to drive the booster pump 400. It can work at sea and effectively convert wave energy into electrical energy to drive the booster pump 400.

[0056] based on Figure 1 In the second type of closed-loop double-arm gas-liquid displacement wave energy generation device proposed in this embodiment, the energy conversion module includes: The magnetic coupler 132 is installed on both sides of the static sealing partition, and the inner rotor of the magnetic coupler 132 is connected to the wet rotor of the water turbine 130 for transmission. The permanent magnet generator 220 is located in an independent dry compartment and is connected to the outer rotor drive of the magnetic coupler 132. The drive module is connected to the permanent magnet generator 220 and transmits the electrical energy output by the permanent magnet generator 220 to the pipeline booster pump 400 to drive the booster pump 400 to work.

[0057] The low-head turbine 130 is connected to the permanent magnet generator 220 located in the dry compartment via a magnetic coupler 132. A static partition separates the turbine 130 side from the generator side. The turbine 130 shaft can transmit torque to the dry permanent magnet generator 220 via the magnetic couplers 132 on both sides of the static sealing partition, eliminating the need for a through-type rotating shaft seal between the working fluid-side impeller and the electrical-side generator 220; alternatively, a sealed coupling or a low-ratio closed gear mechanism can be used. This magnetic coupling scheme reduces the risk of dynamic seal wear and leakage during long-term offshore operation.

[0058] Specifically, the permanent magnet generator 220 allows for power generation over a wide speed range. Its electromagnetic load is regulated by the rectifier converter module, which reduces electromagnetic resistance to prevent turbine 130 stall when the pressure difference is low, and increases the energy extraction load and limits overspeed when the pressure difference is high. The inherent rotational inertia of the turbine 130 and generator rotors can reduce high-frequency torque fluctuations, making a separate large flywheel unnecessary.

[0059] The generator 220 output is connected to the DC bus 250 via a rectifier and voltage regulator module 230. A short-term energy storage module consisting of a supercapacitor 240, a battery, or a combination of both is connected in parallel to the DC bus 250. The energy storage capacity is determined based on the allowable pump downtime and wave intermittency. The DC bus 250 supplies power to the pipeline booster pump motor 401 via a motor driver 260. The booster pump 401 is preferably a variable-speed centrifugal pump, axial-flow pump, or positive displacement pump, and a check valve is installed in the pipeline.

[0060] The controller 270 collects data on the turbine speed (130 rpm), pressure difference across the valve box, DC bus voltage, energy storage charge status, upstream pipeline pressure, and downstream pipeline pressure. When the wave input is sufficient and the pipeline pressure difference is below the target value, the booster pump speed is increased; when energy is insufficient, the pump speed is reduced or intermittent operation is used; when the DC bus voltage is too high, priority is given to charging the energy storage module, and if it still exceeds the limit, a braking resistor or unloading load 280 can be connected.

[0061] This device can function as an independent booster power source or form a hybrid power supply system with shore power, platform power, or other renewable energy sources. Multiple wave energy conversion devices can be connected in parallel to a common DC bus 250 to reduce fluctuations of a single device and facilitate modular maintenance.

[0062] like Figure 6 As shown, the low-head turbine 130 transmits torque to the permanent magnet generator 220 through the magnetic coupler 132, driving the permanent magnet generator 220 to move and generate electricity. The rectifier and voltage regulator module 230 rectifies and regulates the electrical energy output from the permanent magnet generator 220 before inputting it into the DC bus 250. The DC bus 250 then supplies power to the booster pump motor 401 via the motor driver 260.

[0063] The DC bus 250 can be connected in parallel with a supercapacitor 240, a battery, or a combination of both energy storage modules.

[0064] In this system, an upstream pressure sensor 501 and a downstream pressure sensor 502 are respectively installed upstream and downstream of the booster pump 400 in the conveying pipeline 500. The controller 270 collects the pipeline pressure difference, DC bus voltage, and energy storage charge status, and adjusts the booster pump speed according to these parameters.

[0065] Specifically, multiple wave energy conversion devices are connected in parallel to a common DC bus 250, and the common DC bus 250 supplies power to one or more pipeline booster pumps 400.

[0066] It should be noted that, regarding the tuning and installation of the fixed structure of the device, the device does not employ hydraulic push rods or large hinges that change the angle between the two arms during operation. Different models can be formed by selecting the length of the two arms, the fixed angle, and the buoyancy configuration of the hull for different sea areas; during the installation and commissioning phase, the filling rate can be changed by the filling and draining ports, the overall moment of inertia and restoring torque can be changed by the adjustable counterweight, and the gas phase damping and compliance can be adjusted by the gas phase throttling device 112 and the variable volume gas chamber 111.

[0067] During commissioning, based on the dominant wave period and wave height statistics of the target sea area, the filling rate, gas phase throttling opening, and generator 220 electromagnetic load are gradually adjusted under low-risk conditions in the tank or on-site to keep the peak working hydraulic differential, effective flow rate, and roll angle within the design range. The counterweight position can be mechanically adjusted and locked during maintenance, and continuous dynamic movement at sea is not required.

[0068] like Figure 7 As shown, in other closed-loop double-arm gas-liquid displacement wave energy generation devices proposed in this embodiment, the closed-loop double-arm gas-liquid displacement wave energy generation device further includes: The counterweight chamber 150 is located at the bottom of the closed double-arm gas-liquid displacement wave energy power generation device, and is used to make the center of gravity of the closed double-arm gas-liquid displacement wave energy power generation device lower than the center of buoyancy, thereby forming a passive self-righting torque. The mooring assembly 160, located below the counterweight compartment 150, includes a universal joint, a single-point mooring adapter, a tensioning cable or a flexible anchor chain, which enables the enclosed double-arm gas-liquid displacement wave energy generator to adapt to the wave roll while limiting drift, yaw and collision with pipelines. Damping fin 152, located below mooring assembly 160 and connected to mooring assembly 160, is used to reduce high-frequency oscillation; Anchor 162 is located below mooring assembly 160 and is connected to mooring assembly 160; The limiting cable 151 or the limiting block is disposed outside the first liquid arm 101 and the second liquid arm 102 to limit the maximum roll angle.

[0069] The aforementioned device may also include tilt sensors 181 in the first liquid arm 101 and the second liquid arm 102 for detecting the roll angle.

[0070] Optionally, the closed-loop double-arm gas-liquid displacement wave energy generation device also includes; A bypass pressure equalization branch is connected to the first arm common cavity 126 and the second arm common cavity 127. It is used to open during storms, maintenance, startup or shutdown, so that the working fluid 105 in the first liquid arm 101 and the second liquid arm 102 bypasses the turbine 130 and quickly equalizes the pressure. The low-pressure relief valve 141 and the buffer chamber 142 are connected to the integrated bottom manifold valve box 120 and the buffer chamber 142, and are used to suppress instantaneous negative pressure and cavitation.

[0071] Specifically, regarding the mooring, self-righting, and safety protection of the device, the mooring assembly 160 is preferably connected near the roll axis and includes a universal joint, a single-point mooring adapter, a tensioning cable, or a flexible anchor chain. The device is confined to the vicinity of the pipeline pressurization node by single-point mooring, universal joint support, or tensioning mooring, enabling the device to roll with the waves and reciprocate around a predetermined roll axis, while limiting drift, yaw, and collision with the pipeline. The flexible underwater cable 300 is equipped with a stress relief section, and the mooring load is not directly transmitted to the cable or the transport pipeline 500.

[0072] The bottom counterweight tank 150 lowers the center of gravity below the center of buoyancy, creating a passive self-righting moment; external damping fins 152 can be installed to reduce high-frequency oscillations. A limiting cable 151 or a limiting block limits the maximum roll angle. A bypass equalizing valve 140 is installed within the integrated bottom manifold valve box 120 to allow the fluid in both arms to bypass the turbine 130 for rapid pressure equalization during storms, maintenance, startup, or shutdown.

[0073] The valve box may also be equipped with a low-pressure relief valve 141, a buffer chamber 142, a filter 144, and an exhaust structure. The buffer chamber 142 is only used to suppress instantaneous negative pressure and cavitation and is not used as a hectobar-level energy storage unit. When the valve box differential pressure, roll angle, or speed exceeds the threshold, the controller 270 reduces the power generation load and opens the bypass; in the event of control failure, the mechanical differential pressure bypass and the pressure relief structure can still operate.

[0074] The operation and control process of this device is as follows: waves cause the rigid double-arm float to swing alternately around the roll axis. Under the action of gravity and inertia, the working fluid 105 in the two liquid arms forms an alternating port pressure difference. The gas phase balance circuit causes the gas in the two arms to be replaced by the working fluid 105 in the opposite direction. The full-wave liquid flow rectifier bridge automatically selects the first and fourth one-way valves 124 or the second and third one-way valves 123 to be opened according to the pressure difference direction, so that the working fluid 105 flows in the same direction through the turbine inlet manifold 128, the low-head turbine 130 and the turbine outlet diversion chamber 129 in sequence. The turbine 130 drives the generator 220. The electrical energy drives the booster pump 400 according to the pipeline pressure difference requirements after passing through the DC bus 250 and the smooth energy storage. When a storm or failure occurs, the bypass equalizes the pressure and limits the roll.

[0075] In the third type of closed-loop double-arm gas-liquid displacement wave energy generation device proposed in this embodiment, the first liquid arm 101 and the second liquid arm 102 are rigidly welded or flanged to form an angle of approximately 90°. The effective length of each arm is selected according to the target wave condition. Both arms are filled with water-ethylene glycol working fluid, with a filling rate of approximately 55%. Nitrogen is introduced into the top, while maintaining a gas phase space. A gas phase balance connecting pipe 110 is installed at the top of both arms, and the connecting pipe is installed in the area that is still above the liquid surface even at the maximum design roll angle.

[0076] The two outer shells also serve as buoyancy bodies, and the bottom counterweight chamber 150 keeps the device statically in an upward-facing position. The device is moored by a universal joint assembly near the roll axis and anchor 162. When waves arrive, the device generates periodic rolling, creating alternating pressure differentials between the first and second arm liquid common chambers.

[0077] This embodiment enables anti-airlock and gas phase damping adjustment. Vertical liquid-catching sections are installed at both ends of the gas phase balance connecting pipe 110. An adjustable flow element 112 is installed in the pipe, and a bidirectional differential pressure bypass valve 114 is connected in parallel across the throttling element 112. When the gas phase pressure difference is lower than the bypass threshold, the gas flows back and forth through the throttling element 112, generating controllable damping for liquid transfer. When the gas phase pressure difference is too large, the bypass valve opens, quickly balancing the gas pressure in both arms and ensuring that liquid circulation does not stop due to airlock. The variable volume gas chamber 111 is connected to the connecting pipe via a valve and is used to change the gas phase compliance during the installation and commissioning phase.

[0078] The first arm common cavity 126 and the second arm common cavity 127 respectively enter the integrated bottom manifold valve box 120. The first to fourth check valves 124 in the valve box adopt a large-diameter flap structure, and the opening and closing pressure difference is lower than the design minimum driving pressure difference. The turbine inlet manifold cavity 128 and the outlet diversion cavity 129 are located at the center of the valve box, and the flow channels adopt symmetrical rounded corners.

[0079] During the half-cycle when the pressure of the first liquid arm 101 is relatively high, the first check valve 121 and the fourth check valve 124 are opened, and the working fluid 105 flows along the first arm common cavity 126, the first check valve 121, the turbine inlet manifold 128, the turbine 130, the turbine outlet diversion cavity 129 and the fourth check valve 124 to the second arm common cavity 127; During the half-cycle when the pressure in the second hydraulic arm 102 is higher, the second check valve 122 and the third check valve 123 open, and the working fluid 105 flows along the second arm common cavity 127, the second check valve 122, the turbine inlet manifold 128, the turbine 130, the turbine outlet diversion cavity 129, and the third check valve 123 to the first arm common cavity 126. The low-head turbine 130 is connected in series between the inlet manifold 128 and the outlet diversion cavity 129, and receives the same direction of fluid flow from the turbine inlet manifold 128 to the outlet diversion cavity 129 in both half-cycles. After the inspection cover 125 on the top of the valve box is opened, the valve core assembly and the impeller assembly can be extracted as a whole.

[0080] This embodiment can perform magnetic coupling power generation and electrical smoothing. The wet rotor of the turbine 130 is connected to the inner rotor of the magnetic coupler 132, and the permanent magnet generator 220 is located in a separate dry compartment and connected to the outer rotor of the magnetic coupler 132. The working fluid side and the generator 220 side are isolated by a static non-magnetic partition. The output of the permanent magnet generator 220 is rectified and regulated by the rectifier and voltage regulator module 230 to form a DC bus 250. The DC bus 250 is connected in parallel with a supercapacitor 240, and drives the booster pump motor 401 via the motor driver 260.

[0081] This embodiment allows for pressure boosting control based on pipeline pressure differential. Controller 270 adjusts the electromagnetic load of generator 220 according to the DC bus voltage and valve box pressure differential. When the turbine 130 speed is too low, the energy extraction load is reduced; when the speed increases, the load is increased. When the energy storage is full and the bus voltage continues to rise, the unloaded load 280 is connected. This embodiment does not include a 100-bar hydraulic accumulator.

[0082] Pressure sensors are installed upstream and downstream of the booster pump 400 in the delivery pipeline 500. The controller 270 uses the target downstream pressure or target pressure difference as the control variable to adjust the booster pump speed within the allowable range of available wave energy and energy storage. When energy is insufficient, the pump enters a low-speed or intermittent mode; a check valve at the pump outlet prevents backflow during shutdown. Multiple devices can be connected in parallel to the same DC bus 250 to improve power supply continuity.

[0083] Regarding storm and fault protection design, when the pressure difference across the valve box, the roll angle, or the turbine 130 speed exceeds the set value, the controller 270 opens the bypass equalization valve 140 and reduces the load on the generator 220. If the controller 270 fails, the mechanical differential pressure bypass can still open when the pressure difference reaches the set value. The pressure relief valve 141 releases abnormal pressure to the buffer chamber 142, and the low-pressure replenishment chamber 143 replenishes fluid when a momentary negative pressure occurs at the turbine 130 inlet. The limit cable 151 limits the maximum roll angle, the damping fin 152 reduces the sway speed during a storm, and the counterweight tank 150 provides a self-righting torque.

[0084] The closed-loop double-arm gas-liquid displacement wave energy generation device proposed in this embodiment includes a first liquid arm 101 and a second liquid arm 102 rigidly arranged at a fixed angle, a gas phase balance circuit, an integrated bottom manifold valve box 120, a four-valve full-wave liquid flow rectifier bridge, a low-head turbine 130, a permanent magnet power generation and electrical smoothing unit, a mooring self-aligning component, and a pipeline pressurization unit. The gas phase space 106 at the top of the two liquid arms is connected by a bidirectional gas phase balance circuit located above the highest working liquid level, so that the working liquid 105 undergoes reverse gas displacement when transferred between the two arms, avoiding gas lock. The four low opening and closing differential pressure check valves in the integrated bottom manifold valve box 120 open alternately according to the pressure difference direction at the two arm ports, so that the working liquid 105 flows through the low-head turbine 130 in the same direction during both half-cycles of rolling. The turbine 130 preferably drives the permanent magnet generator 220 via a magnetic coupler 132. The electrical energy, after rectification and voltage stabilization, smoothing via the DC bus 250 and energy storage module, drives the booster pump 400 according to the pipeline pressure difference requirements. The device also includes bypass pressure equalization, low-pressure relief, fluid replenishment and cavitation prevention, mooring, self-righting, and limit structures. This embodiment can achieve low-loss, unidirectional energy extraction of the sealed working fluid 105 while avoiding impedance mismatch in the high-pressure hydraulic link, making it suitable for auxiliary pressurization of offshore pipelines and distributed energy supply.

[0085] It should be noted that this embodiment uses closed-arm wave energy generation as its core. During normal operation, it does not rely on continuous external fuel or long-distance power supply, but obtains electricity locally using sea surface waves. The generated electricity is then stably used to drive the booster pump 400 of the marine fluid transport pipeline 500. This embodiment is not a simple connection between a conventional wave energy generation device and the booster pump 400, but rather a complete technical chain that enables continuous operation under random sea conditions, encompassing wave capture, internal fluid conversion, power generation, electrical smoothing, and pipeline pressure control. This embodiment addresses the following technical issues regarding how the working fluid 105 inside the closed-arm can continuously, with low loss, and harvest energy in the same direction under real sea conditions: (1) When liquid transfer occurs between the closed double arms in the related technology, the gas phase pressure difference may form an airlock. In this embodiment, a bidirectional gas phase balance circuit is set above the highest working liquid level, so that the gas on the receiving side enters the supply side in reverse, and the gas phase pressure difference is limited by differential pressure bypass.

[0086] (2) The alternating roll direction in related technologies leads to alternating liquid flow direction, making it difficult for ordinary water turbines to rotate continuously in the same direction. In this embodiment, four low opening and closing pressure differential check valves are used to form a full-wave liquid flow rectification bridge. The conduction combination is automatically switched according to the pressure differential direction of the two arms. A pair of valves is opened under the two pressure differential directions respectively, so that the inlet and outlet directions of the water turbine 130 remain unchanged. The water turbine 130 does not need to repeatedly change direction, thus achieving full-wave unidirectional energy extraction.

[0087] (3) The available head in related technologies is limited, and the local resistance caused by ordinary cross pipes and valves is too large. In this embodiment, the two arm ports, four valves, short flow channels, turbine casing, bypass and maintenance structure are integrated into a bottom manifold valve box, shortening the flow channel and adopting rounded corner transition. Specifically, the integrated manifold valve box integrates the common port, four valves, short flow channels and turbine 130, reducing long pipes, elbows and cross connections, and reducing internal losses under limited head.

[0088] (4) The low head and high flow energy in the related technology are not matched with the impedance of the high pressure hydraulic energy storage link. In this embodiment, a smooth electrical link is adopted with a low head turbine 130, permanent magnet generator 220, rectifier, DC bus 250 and supercapacitor 240 / battery, so as not to forcibly convert the low pressure and high flow energy into 100 bar hydraulic energy and avoid energy impedance mismatch.

[0089] (5) The dynamic adjustment of the angle of the large double arms in the related technology is complex and has a high risk of fatigue in the marine environment. In this embodiment, the double arms adopt a rigid fixed angle, and the response is adjusted by the filling rate, the counterweight position during the commissioning period, the gas phase damping and the variable volume air chamber 111.

[0090] (6) In related technologies, float drift, yaw, or lack of reaction force can weaken roll energy harvesting and affect the safety of subsea pipelines. This embodiment sets up single-point mooring, universal joint support, or tensioned mooring to allow the device to roll but limit drift, and to decouple the mooring load from the pipeline load.

[0091] (7) In related technologies, overcurrent, cavitation, overpressure and excessive roll may occur under storm conditions. This embodiment is equipped with passive priority bypass pressure equalization, pressure relief, low pressure liquid replenishment, self-righting counterweight, damping fin 152 and limiting structure.

[0092] This embodiment also reduces the risk of sealing maintenance, as the working fluid 105 is isolated from seawater, magnetic coupling drive is preferred, and the number of through-type rotary shaft seals is reduced.

[0093] The device structure in this embodiment is adjustable but not overly complex. The angle between the two arms is fixed, and it is matched by the liquid filling rate, the counterweight during the commissioning period, and the gas phase damping to avoid large dynamic hinge mechanisms.

[0094] The device in this embodiment possesses maritime survivability. Mooring decoupling, counterweight self-righting, damping fin 152, limiters, bypass, and mechanical depressurization work together to cope with extreme sea conditions.

[0095] The device in this embodiment is adapted to the actual needs of the pipeline. The pump speed is adjusted based on the pipeline pressure difference and available energy, and it can operate independently or be integrated into a hybrid energy supply system.

[0096] like Figure 8 As shown, this embodiment proposes a booster pump operation control method, which is applied to any of the above-mentioned closed double-arm gas-liquid displacement wave energy power generation devices. The method includes: S801. Monitor the target parameter values ​​and wave energy-related parameter values ​​of the booster delivery pipeline; wherein, the booster delivery pipeline is the pipeline where the booster pump is located, the target parameter is the downstream pressure or the pressure difference between upstream and downstream of the booster delivery pipeline, and the wave energy-related parameter value is at least one of the pressure difference between the two ends of the integrated bottom manifold valve box, the turbine speed, and the roll angle.

[0097] Specifically, in this embodiment, pressure sensors are installed upstream and downstream of the booster pump in the delivery pipeline. The controller uses the target downstream pressure or target pressure difference as the control variable to adjust the booster pump speed within the range allowed by available wave energy and energy storage.

[0098] The controller can collect data such as turbine speed, pressure difference across the valve box, DC bus voltage, energy storage charge status, upstream and downstream pressure of the pipeline, and control the operation of the booster pump based on the collected data.

[0099] S802. If it is determined that the booster pump has sufficient power supply based on the wave energy related parameter values, and the target parameter value is lower than the set value, then the speed of the booster pump is controlled to be within the set high-speed range.

[0100] Specifically, when the wave input is sufficient and the pipeline pressure difference is lower than the target value, the controller can increase the booster pump speed. When energy is insufficient, the controller can reduce the pump speed or operate intermittently; when the DC bus voltage is too high, it prioritizes charging the energy storage module, and when the energy storage is full and the bus voltage continues to rise, it can connect a braking resistor or unload the load.

[0101] S803. If it is determined from the relevant wave energy parameters that the booster pump is not providing enough power, then control the speed of the booster pump to be within the set low speed range or enter the intermittent operation mode.

[0102] When energy is insufficient, the pump enters low-speed or intermittent mode; the pump outlet check valve prevents backflow during shutdown. Multiple units can be connected in parallel to the same DC bus to improve power supply continuity.

[0103] It should be noted that when the gas phase pressure difference in the gas phase balance loop exceeds the threshold, the controller can open the bidirectional differential pressure bypass valve to prevent the tuning damping from becoming airlocked. When the pressure difference across the valve box, the roll angle, or the turbine speed exceeds the set value, the controller can open the bypass equalization valve and reduce the generator load. If the controller fails, the mechanical differential pressure bypass can still open when the pressure difference reaches the set value. The pressure relief valve releases abnormal pressure to the buffer chamber, and the low-pressure replenishment chamber 143 replenishes liquid when a momentary negative pressure occurs at the turbine inlet. The limit cable limits the maximum roll angle, the damping fins reduce the sway speed in a storm, and the counterweight tank provides a self-righting torque.

[0104] The booster pump operation control method proposed in this embodiment can achieve the following technical effects: (1) Eliminate gas lock. The gas phase balance circuit reverses the flow of gas from the receiving side to the supply side and limits the gas phase pressure difference through differential pressure bypass.

[0105] (2) Achieve full-wave unidirectional energy extraction. The four check valves automatically switch their conduction combinations according to the pressure difference direction between the two arms, eliminating the need for the turbine to repeatedly change direction.

[0106] (3) Reduce internal losses under limited head. The integrated manifold box integrates the common port, four valves, short flow channel and turbine, reducing long pipes, bends and cross connections.

[0107] (4) Avoid energy impedance mismatch. Use low-head turbines, wide-speed permanent magnet generators and electrical side energy storage to avoid forcibly converting low-pressure, high-flow energy into hydraulic energy at the hundred-bar level.

[0108] (5) Reduce the risk of seal maintenance. The working fluid is isolated from seawater, magnetic coupling drive is preferred, and the number of through-type rotary shaft seals is reduced.

[0109] (6) The structure is adjustable but not overly complex. The angle between the two arms is fixed and matched by the liquid filling rate, the counterweight during the commissioning period and the gas phase damping to avoid large dynamic articulation mechanisms.

[0110] (7) Possesses maritime survivability. Mooring decoupling, counterweight self-righting, damping fins, limiters, bypass, and mechanical depressurization work together to cope with extreme sea conditions.

[0111] (8) Adapt to the actual needs of the pipeline. The pump speed can be adjusted based on the pipeline pressure difference and available energy, and it can operate independently or be integrated into a hybrid energy supply system.

[0112] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A closed-loop double-arm gas-liquid displacement wave energy generation device, characterized in that, include: The wave capture body includes a first liquid arm and a second liquid arm located on both sides of a preset roll axis and arranged in a bifurcated symmetrical manner; wherein, the first liquid arm and the second liquid arm are closed buoyancy box-shaped cavities that generate roll under the action of ocean waves, and the interior includes a top gas phase space, a working liquid cavity and a working liquid. A gas phase balance circuit is formed by connecting the top gas phase space of the first liquid arm and the second liquid arm through a pipeline. The circuit is positioned above the highest working liquid level of the first liquid arm and the second liquid arm to balance the gas pressure of the first liquid arm and the second liquid arm and prevent gas lock. An integrated bottom manifold valve box is installed in the lower region of the first liquid arm and the second liquid arm, and a pipe connects the bottom end of the first liquid arm and the bottom end of the second liquid arm; wherein, the working fluid is affected by ocean waves and flows back and forth between the first liquid arm, the integrated bottom manifold valve box and the second liquid arm; The energy conversion module connects the integrated bottom manifold valve box and the booster pump, and is used to convert the mechanical energy of the working fluid into electrical energy through the integrated bottom manifold valve box to drive the booster pump.

2. The apparatus according to claim 1, characterized in that, The integrated bottom manifold valve box is equipped with; The common cavity of the first arm is located below the lowest working liquid level in the first liquid arm. It is connected to the bottom end of the first liquid arm by a pipe, equipped with an anti-vortex guide cover, and remains submerged at the maximum design roll angle. The common cavity of the second arm is located below the lowest working liquid level in the second liquid arm. It is connected to the bottom end of the second liquid arm by a pipe, equipped with an anti-vortex guide cover, and remains submerged at the maximum design roll angle. A full-wave liquid flow rectifier bridge is located between the common cavity of the first arm and the common cavity of the second arm; Under the action of ocean waves, an alternating pressure difference is formed between the first arm common cavity and the second arm common cavity, and the working fluid flows back and forth between the first arm common cavity, the full-wave liquid flow rectification bridge and the second arm common cavity.

3. The apparatus according to claim 2, characterized in that, The full-wave liquid flow rectifier bridge includes: The first check valve has its inlet end connected to the common cavity of the first arm. The second check valve has its inlet end connected to the common chamber of the second arm. The turbine inlet manifold has its input end connected to the outlet end of the first check valve and the outlet end of the second check valve. The water turbine's input end is connected to the output end of the water turbine's inlet manifold. The turbine outlet diversion chamber has its input end connected to the turbine's output end. The third check valve has its inlet end connected to the output end of the turbine outlet diversion chamber and its outlet end connected to the common chamber of the first arm. The fourth check valve has its inlet end connected to the output end of the turbine outlet diversion chamber, and its outlet end connected to the common chamber of the second arm.

4. The apparatus according to claim 3, characterized in that, When the pressure in the first arm common cavity is higher than the pressure in the second arm common cavity, the working fluid flows along the first arm common cavity, the first check valve, the turbine inlet manifold, the turbine, the turbine outlet diversion cavity, and the fourth check valve to the second arm common cavity; When the pressure in the second arm common cavity is higher than the pressure in the first arm common cavity, the working fluid flows along the second arm common cavity, the second check valve, the turbine inlet manifold, the turbine, the turbine outlet diversion cavity, and the third check valve to the first arm common cavity.

5. The apparatus according to claim 1, characterized in that, The gas-phase equilibrium loop includes: A gas phase balance connecting pipe connects the top gas phase spaces of the first liquid arm and the second liquid arm at both ends; An adjustable flow element is installed in the middle section of the gas phase balance connecting pipe to change the gas reciprocating flow damping, thereby adjusting the working fluid response amplitude and phase. A two-way differential pressure bypass valve is connected in parallel to both ends of the adjustable flow element. It is used to open when the gas phase pressure difference between the two arms exceeds the set value, so as to prevent the tuning damping from becoming a gas lock. A variable volume gas chamber is provided on the gas phase balance connecting pipe to change the gas phase equivalent compliance; A gas-liquid separation chamber or a vertical liquid-catching section is provided at both ends of the gas phase balance connecting pipe to prevent the working fluid from entering the gas path during large swaying.

6. The apparatus according to claim 1, characterized in that, The energy conversion module includes: A magnetic coupler is installed on both sides of a static sealing partition, and the inner rotor of the magnetic coupler is connected to the wet rotor of the water turbine. A permanent magnet generator is located in an independent dry compartment and is connected to the outer rotor of the magnetic coupler. The drive module is connected to the permanent magnet generator and transmits the electrical energy output by the permanent magnet generator to the pipeline booster pump to drive the booster pump to work.

7. The apparatus according to claim 1, characterized in that, The first liquid arm and the second liquid arm are arranged symmetrically in a V-shape or Y-shape on both sides of the preset rocking shaft.

8. The apparatus according to claim 1, characterized in that, The closed-loop double-arm gas-liquid displacement wave energy generation device also includes: The counterweight chamber is located at the bottom of the closed double-arm gas-liquid displacement wave energy power generation device, and is used to make the center of gravity of the closed double-arm gas-liquid displacement wave energy power generation device lower than the center of buoyancy, thereby forming a passive self-righting torque. The mooring assembly, located below the counterweight compartment, includes a universal joint, a single-point mooring adapter, a tensioning cable, or a flexible anchor chain, which enables the enclosed double-arm gas-liquid displacement wave energy generation device to adapt to the wave roll while limiting drift, yaw, and collision with pipelines. A damping fin, located below the mooring assembly and connected to the mooring assembly, is used to reduce high-frequency oscillation. An anchor, located below the mooring assembly, connects to the mooring assembly; A limiting cable or limiting block is disposed outside the first and second liquid arms to limit the maximum roll angle.

9. The apparatus according to claim 3, characterized in that, The closed double-arm gas-liquid displacement wave energy power generation device also includes; A bypass pressure equalization branch is connected to the common cavity of the first arm and the common cavity of the second arm. It is used to open during storms, maintenance, startup or shutdown, so that the working fluid in the first liquid arm and the second liquid arm bypasses the turbine and quickly equalizes the pressure. A low-pressure relief valve and a buffer chamber are provided. The low-pressure relief valve is connected to the integrated bottom manifold box and the buffer chamber to suppress instantaneous negative pressure and cavitation.

10. A method for controlling the operation of a booster pump, characterized in that, The method applied to the closed-loop double-arm gas-liquid displacement wave energy generation device according to any one of claims 1 to 9 includes: Monitor the target parameter values ​​and wave energy-related parameter values ​​of the booster delivery pipeline; wherein, the booster delivery pipeline is the pipeline where the booster pump is located, the target parameter is the downstream pressure or the pressure difference between the upstream and downstream of the booster delivery pipeline, and the wave energy-related parameter value is at least one of the pressure difference between the two ends of the integrated bottom manifold valve box, the turbine speed, and the roll angle; If it is determined that the booster pump has sufficient power supply based on the wave energy related parameter values, and it is determined that the target parameter value is lower than the set value, then the speed of the booster pump is controlled to be within the set high-speed range. If the power supply of the booster pump is insufficient based on the wave energy-related parameter values, the speed of the booster pump is controlled to be within a set low speed range or to enter an intermittent operation mode.

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