A pneumatic-hydraulic hybrid wave energy device energy conversion system

Abstract

The application discloses a kind of pneumatic-hydraulic hybrid wave energy device energy conversion systems, including nozzle, impulse turbine, torque output shaft, shaft coupling, rotational speed sensor, variable displacement pump, energy accumulator, manual reversing valve, first electromagnetic ball valve, second electromagnetic ball valve, hydraulic motor, permanent magnet generator, PID control module, hydraulic oil tank, oil pressure sensor, first hysteresis comparator, second hysteresis comparator, air pressure sensor and overflow valve.The application realizes an innovative pneumatic-hydraulic energy conversion mode by combining air turbine and hydraulic conversion system.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of pneumatic and hydraulic energy conversion and control systems of wave energy power generation devices, in particular to a pneumatic-hydraulic hybrid wave energy device energy conversion system. BACKGROUND

[0002] Ocean wave energy is a clean and renewable energy, and the development and utilization of wave energy is of great significance to improve the environmental pollution problems caused by the use of fossil energy. There are various types of wave energy devices, but from the wave energy conversion principle, wave energy devices can be divided into several categories such as pneumatic, hydraulic, hydraulic and special motor types. Most of the currently developed wave energy devices use pneumatic and hydraulic power generation principles.

[0003] Among them, the pneumatic wave energy power generation device has the following advantages: first, the energy conversion system of the pneumatic wave energy device is simple in structure, usually composed of a nozzle, an air turbine and a permanent magnet generator, so the failure rate is low and easy to maintain; second, the pneumatic wave energy power generation device uses the relative motion between a single floating body and a water column to do work, so there is no collision problem between rigid floats; third, the power conversion component of the pneumatic wave energy device is an air turbine, which is directly connected coaxially with the permanent magnet generator, and the air turbine itself does not have relative motion, so there is no sealing problem. Due to these advantages, the pneumatic wave energy device has strong survivability in the ocean and is very high in maintainability. The disadvantages of the pneumatic wave energy power generation device are: first, there is no energy storage link in the entire process from wave energy to electric energy, resulting in very unstable power output, which has a large impact on the battery and power grid. And due to the randomness of waves, the peak power can reach 10 times the average power, so it is necessary to match the installed power of the generator which is 10 times the average incoming wave power. A high-power generator not only leads to increased costs, but also in small wave conditions, the shaft power output of the air turbine does not match it, resulting in low conversion efficiency. Second, the pneumatic wave energy device needs to inhale and exhale, so the part of the air turbine and the generator connected coaxially is out of the sea steam, and the sea steam easily enters the inside of the generator through the shaft gap of the generator, corrodes the electrical elements and bearings inside the generator, and causes the generator to be easily damaged.

[0004] The hydraulic wave energy generator generally utilizes the relative movement between double floating bodies or multiple floating bodies to drive the reciprocating movement of the power component (mainly a hydraulic cylinder), and then the hydraulic cylinder pumps into an energy accumulator to generate electricity after energy storage and pressure stabilization. The advantages mainly lie in the following aspects: first, it has an energy storage and pressure stabilization link, can accumulate the wave energy under small waves, and generate electricity at 0-1, thereby improving the power generation efficiency, and after energy storage and pressure stabilization, the energy of the generated electricity is stable, which is convenient for charging the battery or inputting the power grid. Second, it is convenient to judge the wave power size by measuring the pressure of the energy accumulator, thereby enabling the device to perform self-protection control under large waves. However, the disadvantages of the hydraulic wave energy generator are also obvious: first, the piston rod and cylinder barrel of the power component hydraulic cylinder are in relative motion at all times and are placed in seawater or sea steam, and the dynamic sealing problem is difficult to solve, which makes it one of the most prone to failure components of the hydraulic wave energy generator; second, the multiple floating bodies have a collision problem.

[0005] In general, the reliability and maintainability of the pneumatic wave energy generator are high, but the power generation quality is relatively poor, the conversion efficiency is low, and the generator is prone to failure; the characteristics of the hydraulic wave energy generator are opposite, and the reliability is relatively poor, and the power generation efficiency and stability are relatively high. Therefore, how to improve the power generation stability and conversion efficiency of the pneumatic wave energy generator has become a problem to be solved for the pneumatic wave energy generator. SUMMARY

[0006] The present disclosure provides a kind of pneumatic-hydraulic hybrid wave energy device energy conversion system to solve one of the technical problems that the inventor realizes.

[0007] The present disclosure provides a kind of pneumatic-hydraulic hybrid wave energy device energy conversion system, comprising nozzle, impulse turbine, torque output shaft, proportional displacement pump, manual reversing valve, energy accumulator group, hydraulic motor, hydraulic oil tank, permanent magnet generator, the nozzle and impulse turbine are embedded in the upper of air chamber, the impulse turbine is connected with the one end of torque output shaft through key groove, the other end of torque output shaft is connected with the shaft of variable proportional displacement pump through coupling, the oil inlet of variable proportional displacement pump is connected with the hydraulic oil tank, the oil outlet of variable proportional displacement pump is connected with the energy accumulator group through the manual reversing valve, one end of the manual reversing valve is communicated with the hydraulic oil tank, the oil outlet of the energy accumulator group is connected with the oil inlet of first electromagnetic ball valve, the oil outlet of first electromagnetic ball valve is connected with the input port of hydraulic motor, the hydraulic motor is coaxially connected with the permanent magnet generator.

[0008] Preferably, a rotational speed sensor is arranged on the torque output shaft, and a wiring end of the rotational speed sensor is connected with a PID control module, and the PID control module is connected with a signal line control interface of the variable proportional displacement pump.

[0009] Preferably, the control end of the first electromagnetic ball valve is connected with a first hysteresis comparator, and the first hysteresis comparator is connected with an oil pressure sensor.

[0010] Preferably, the air chamber is provided with a side branch, the side branch is connected with an inlet end of a second electromagnetic ball valve, and an outlet end of the second electromagnetic ball valve is communicated with the atmosphere.

[0011] Preferably, the side branch is provided with an air pressure sensor, a control end of the air pressure sensor is connected with one end of a second hysteresis comparator, and the other end of the second hysteresis comparator is connected with the second electromagnetic ball valve.

[0012] Preferably, an overflow valve is arranged between the accumulator group and the hydraulic oil tank.

[0013] The beneficial effects of the present disclosure mainly lie in:

[0014] 1. The present application realizes an innovative pneumatic-hydraulic energy conversion mode by combining an air turbine and a hydraulic conversion system.

[0015] 2. The present application has the characteristics of energy storage and pressure stabilization, so that the pneumatic wave energy generator has high reliability and improved power generation stability.

[0016] 3. The present application adds a self-protection function of the pneumatic wave energy generator under large waves to the pneumatic-hydraulic hybrid wave energy device energy conversion system, and further improves the survival ability of the wave energy device energy conversion system under typhoon and other severe sea conditions.

[0017] 4. The adjustable hydraulic load is adopted, so that the variable displacement pump can adjust the displacement in real time according to the speed of the air turbine (i.e. the size of the incoming wave power), so as to realize real-time matching of the back-end load of the wave energy device and the incoming wave power, and improve the conversion efficiency of the energy conversion system.

[0018] It should be understood that both the foregoing general description and the following detailed description are intended for purposes of illustration and description only and are not intended to limit the present disclosure. The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate the subject matter of the present disclosure. Meanwhile, the specification and the drawings serve to explain the principles of the present disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the specific embodiments of the present disclosure or the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or prior art description. Obviously, the drawings described below are only some embodiments of the present disclosure, and the ordinary skilled in the art can obtain other drawings according to these drawings without creative effort.

[0020] Figure 1 Figure of the wave energy device pneumatic-hydraulic hybrid energy conversion system disclosed by the present application;

[0021] Figure: 1-nozzle, 2-impulse turbine, 3-torque output shaft, 4-coupling, 5-rotational speed sensor, 6-variable displacement pump, 7-accumulator group, 8-hand-operated reversing valve, 9-first electromagnetic ball valve, 10-second electromagnetic ball valve, 11-constant-displacement hydraulic motor, 12-permanent magnet generator, 13-PID control module, 14-oil tank, 15-oil pressure sensor, 16-first hysteresis comparator, 17-second hysteresis comparator, 18-air pressure sensor, 19-relief valve. DETAILED DESCRIPTION

[0022] The technical solutions of the present disclosure will be described in detail below with reference to the drawings. Obviously, the described embodiments are only some of the embodiments of the present disclosure, not all the embodiments.

[0023] Based on the embodiments in the present disclosure, all other embodiments obtained by the ordinary skilled in the art without creative effort are within the scope of protection of the present disclosure.

[0024] In the description of the present disclosure, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present disclosure. In addition, the terms "first", "second", "third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0025] In the description of the present disclosure, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integral connection; it can be mechanical connection, or electrical connection; it can be direct connection, or indirect connection through intermediate medium, or internal communication of two elements. For the ordinary skilled in the art, the specific meaning of the above terms in the present disclosure can be understood according to the specific circumstances.

[0026] Embodiment

[0027] As Figure 1 shown, the embodiment provides a kind of pneumatic-hydraulic hybrid wave energy device energy conversion system, including nozzle 1, impulse turbine 2, torque output shaft 3, coupling 4, rotational speed sensor 5, variable displacement pump 6, energy accumulator, manual reversing valve 8, first electromagnetic ball valve 9, second electromagnetic ball valve 10, hydraulic motor 11, permanent magnet generator 12, PID control module 13, hydraulic oil tank 14, oil pressure sensor 15, first hysteresis comparator 16, second hysteresis comparator 17, air pressure sensor 18 and overflow valve 19.

[0028] Specifically, the nozzle 1 is installed in the exhaust port of the air chamber, wherein the air chamber is an oscillating water column type wave energy air chamber, the air outlet of the air chamber is provided with an impulse turbine 2, the nozzle 1 and the impulse turbine 2 form the power component of the pneumatic wave energy device, the impulse turbine 2 is connected to the torque output shaft 3 through a key groove, and the torque output shaft 3 is connected to the shaft of the variable displacement pump 6 through the coupling 4 away from the impulse turbine 2, so that the variable displacement pump 6 and the impulse turbine 2 rotate in the same direction and at the same speed, the oil inlet of the variable displacement pump 6 is communicated with the hydraulic oil tank 14, the oil outlet of the variable displacement pump 6 is communicated with the G port of the manual reversing valve 8, the E port of the manual reversing valve 8 is communicated with the energy accumulator group 7, the F port of the manual reversing valve 8 is communicated to the hydraulic oil tank 14, the energy accumulator group 7 is provided with an oil pressure sensor 15 for measuring the pressure of the energy accumulator group 7, the oil outlet of the energy accumulator group 7 is communicated to the oil inlet C port of the first electromagnetic ball valve 9, the oil outlet D port of the first electromagnetic ball valve 9 is communicated to the inlet of the hydraulic motor 11, and the shaft of the hydraulic motor 11 is coaxially connected to the permanent magnet generator 12.

[0029] Further, the torque output shaft 3 is provided with a rotational speed sensor 5, the rotational speed sensor 5 is used to measure the rotational speed of the impulse turbine 2 in real time, and the node segment of the rotational speed sensor 5 is connected to the PID control module 13, the PID control module 13 is connected to the variable displacement pump 6, and the PID control module 13 can automatically adjust the displacement of the variable displacement pump 6 by detecting the rotational speed of the rotational speed sensor 5.

[0030] Further, the control end of the oil pressure sensor 15 is connected to the first hysteresis comparator 16, the first hysteresis comparator 16 is connected to the control end of the first electromagnetic ball valve 9, and the opening and closing of the first electromagnetic ball valve 9 can be controlled.

[0031] Further, the air chamber is provided with a side branch, the side branch is communicated with the inlet end B of the second electromagnetic ball valve 10, and the outlet end A of the second electromagnetic ball valve 10 is communicated with the atmosphere.

[0032] Further, the side branch is provided with an air pressure sensor 18 for measuring the air pressure in the air chamber, the control end of the air pressure sensor 18 is connected to the second hysteresis comparator 17, and the control end of the second hysteresis comparator 17 is connected to the control end of the second electromagnetic ball valve 10, so that the opening and closing of the second electromagnetic ball valve 10 can be controlled.

[0033] Further, the accumulator group 7 and the hydraulic oil tank 14 are provided with an overflow valve 19.

[0034] The pneumatic wave energy generation technology generally adopts an air chamber to capture wave energy, the air chamber is a structure with an open bottom, when waves act on the open structure, the water column in the air chamber moves up and down, thereby capturing the energy of the waves. The traditional pneumatic wave energy technology is composed of an air chamber, an air impeller and a generator, the oscillating water column pushes the air in the air chamber to reciprocate, and the air drives the generator to generate electricity through the impeller.

[0035] The present application provides a pneumatic-hydraulic hybrid wave energy device energy conversion system, which increases the hydraulic energy conversion components on the basis of generating electricity, when waves act on the oscillating water column in the air chamber, the water column compresses the air in the upper part of the air chamber to form a reciprocating air flow, after passing through the nozzle 1, the reciprocating air flow drives the impulse turbine 2 to rotate in one direction, a torque output shaft 3 is arranged on the high-speed rotating impulse turbine 2 and rotates synchronously with the impulse turbine 2, a rotational speed sensor 5 is arranged on the torque output shaft 3 and can measure the rotational speed of the torque output shaft 3 in real time, and the torque output shaft 3 is connected with the variable displacement pump 6 through the shaft coupling 4, therefore, the impulse turbine 2 driven by the reciprocating air flow will drive the variable displacement pump 6 to rotate in one direction, and the conversion from air compression energy to rotary mechanical energy is realized.

[0036] When the variable displacement pump 6 rotates in one direction, the hydraulic oil is sucked from the hydraulic oil tank 14, pressurized by the variable displacement pump 6 and output from the outlet, and the rotary mechanical energy is converted into hydraulic energy.

[0037] The measurement signal end of the rotational speed sensor 5 is connected with the PID control module 13, the control end of the PID control module 13 is connected to the control signal end of the variable displacement pump 6, the PID control module 13 controls the displacement of the variable displacement pump 6 by judging the rotational speed of the torque output shaft 3, and the variable displacement pump 6 can adjust the output power in real time according to the wave, and the efficiency of the pneumatic wave energy conversion system is improved.

[0038] The hydraulic oil of the variable displacement pump 6 outlet enters the hand-operated reversing valve 8. In normal state, the valve core is in the right position, the G port and the E port of the hand-operated reversing valve 8 are communicated, the F port is disconnected, the high-pressure hydraulic oil enters the accumulator group 7 through the hand-operated reversing valve 8 to be stored, and a pressure sensor is installed on the pipeline entering the accumulator group 7. The pressure of the accumulator group 7 can be measured in real time through the pressure sensor. The measurement signal of the pressure sensor is connected with the first hysteresis comparator 16. The first hysteresis comparator 16 determines whether to output voltage to the first electromagnetic ball valve 9 and the electromagnetic controlled end by detecting the signal of the first pressure sensor. When the system fails and needs to be repaired, the handle of the hand-operated reversing valve 8 can be pushed to the left, the valve core moves to the left, the G port and the F port of the hand-operated reversing valve 8 are communicated, and the E port is disconnected. The hydraulic oil of the variable displacement pump 6 outlet flows back to the oil tank. When the repair is completed, the handle of the hand-operated reversing valve 8 is released, the valve core returns to the right position under the action of the return spring, and the system returns to the normal working state.

[0039] The control logic of the hysteresis comparator controller is as follows. In the initial state, there is no voltage signal output in the 0 state. When the pressure gradually rises to po, the voltage signal is output, which is state 1. If the pressure continues to rise, the 1 state will continue. When the pressure drops but does not reach pc, the 1 state is still maintained. When the pressure drops to pc, the voltage signal output stops, and the system is in the 0 state, and the next cycle begins.

[0040] The outlet of the accumulator group 7 is connected to the C port of the first electromagnetic ball valve 9. In the initial state, the valve core of the first electromagnetic ball valve 9 is in the left position, and the C port and the D port of the first electromagnetic ball valve 9 are disconnected. When the pressure of the hydraulic oil input to the accumulator group 7 from the variable displacement pump 6 rises to the set pressure P2, the first hysteresis comparator 16 outputs the voltage signal to the electromagnetic control end of the first electromagnetic ball valve 9. After the electromagnetic control end of the first electromagnetic ball valve 9 receives the voltage signal, the valve core moves to the right, the C port and the D port of the first electromagnetic ball valve 9 are communicated, and the high-pressure hydraulic oil in the accumulator group 7 is released to the inlet of the hydraulic motor 11 to drive the hydraulic motor 11 to rotate at high speed. The hydraulic motor 11 is coaxially connected with the permanent magnet generator 12, drives the permanent magnet generator 12 to rotate, and then generates electricity, realizing the process of converting hydraulic energy into electrical energy.

[0041] If the wave energy is large at this time, the reciprocating air flow speed is fast, so that the rotational speed of the impulse turbine 2 and the variable displacement pump 6 is also fast, the flow of the hydraulic oil into the accumulator group 7 by the variable displacement pump 6 is large, which is greater than the flow of the hydraulic oil output from the accumulator group 7 to the hydraulic motor 11, the pressure of the accumulator group 7 will continue to rise until the safety overflow pressure, the overflow valve 19 opens to implement overflow, so that the pressure of the accumulator group 7 does not exceed the set safety overflow pressure, because the pressure of the accumulator group 7 is always greater than P2, so the valve core of the first electromagnetic ball valve 9 is always in the right position, the C port and the D port are always in communication, and the system continuously generates electricity.

[0042] If the wave energy is relatively small at this time, the reciprocating air flow speed is slow, so that the rotational speed of the impulse turbine 2 and the variable displacement pump 6 is also slow, the flow of the hydraulic oil into the accumulator group 7 by the variable displacement pump 6 is small, which is less than the flow of the hydraulic oil output from the accumulator group 7 to the hydraulic motor 11, the pressure of the accumulator group 7 will decrease until it decreases to the set closing pressure P1, the voltage signal of the first hysteresis comparator 16 will stop, after the electromagnetic control end of the first electromagnetic ball valve 9 has no voltage signal, the valve core returns to the left position under the action of the left end return spring, the C port and the D port will be disconnected, the hydraulic oil of the accumulator group 7 will stop releasing to the hydraulic motor 11, the system stops generating electricity, and the accumulator group 7 will start the next accumulation process, and the system is in an intermittent power generation state.

[0043] In addition, the side wall of the air chamber is provided with the second electromagnetic ball valve 10 and the air pressure pressure sensor 18, when the electromagnetic ball valve is opened, the high-pressure air in the air chamber can be released to the atmosphere, so that the high pressure in the air chamber does not cause the rotational speed of the impulse turbine 2 to increase rapidly and possibly greatly exceed the rated rotational speed of the impulse turbine 2, thereby causing damage to the air chamber and the system.

[0044] The opening and closing of the second electromagnetic ball valve 10 is controlled by the second hysteresis comparator 17, in the initial state, the valve core of the second electromagnetic ball valve 10 is in the right position, and the A port and the B port of the second electromagnetic ball valve 10 are disconnected. Under normal wave conditions, the air pressure in the air chamber will not exceed the set opening pressure value P4 of the second electromagnetic ball valve 10, so the second electromagnetic ball valve 10 is always in the closed state, that is, always maintains the initial state. When a typhoon occurs, the wave power is large, and the air pressure in the air chamber also rises rapidly, when the pressure in the air chamber rises to the set P4, the second hysteresis comparator 17 will output a voltage signal to the electromagnetic control end of the second electromagnetic ball valve 10, after the electromagnetic control end of the second electromagnetic ball valve 10 receives the voltage signal, the valve core moves to the left, and the A port and the B port of the second electromagnetic ball valve 10 are connected, at this time, part of the air pressure in the air chamber will be released to the air through the electromagnetic ball valve.

[0045] When the typhoon and other bad sea conditions retreat, the incoming wave power decreases, and the air pressure in the air chamber also decreases accordingly. When the air pressure decreases to P3, the voltage signal of the second hysteresis comparator 17 will stop, and the second electromagnetic ball valve 10 has no voltage signal at the electromagnetic control end. Under the action of the right end return spring, the valve core returns to the right position, the A port and the B port are disconnected, and the second electromagnetic ball valve 10 is closed.

[0046] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present disclosure, and not to limit them; although the present disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present disclosure.

Claims

1. A pneumatic-hydraulic hybrid wave energy device energy conversion system, characterized by, The utility model relates to a kind of hydraulic system, including: nozzle, impulse turbine, torque output shaft, variable displacement pump, manual reversing valve, accumulator group, hydraulic motor, hydraulic oil tank, permanent magnet generator, the nozzle and impulse turbine are embedded in the top of air chamber, the impulse turbine is connected with the one end of the torque output shaft by key groove, the torque output shaft other end is connected with the shaft of the variable displacement pump by shaft coupling, the oil inlet of the variable displacement pump is connected with the hydraulic oil tank, the oil outlet of the variable displacement pump is connected with the accumulator group by the manual reversing valve, the manual reversing valve one end is communicated with the hydraulic oil tank, the oil outlet of the accumulator group is connected with the oil inlet of first electromagnetic ball valve, the oil outlet of first electromagnetic ball valve is connected with the input of the hydraulic motor, and the hydraulic motor is coaxially connected with the permanent magnet generator;The torque output shaft is provided with speed sensor, and the wiring end of the speed sensor is connected with PID control module, and the PID control module is connected with the signal line control interface of the variable displacement pump;The control end of the first electromagnetic ball valve is connected with first hysteresis comparator, and the first hysteresis comparator is connected with oil pressure pressure sensor;Second electromagnetic ball valve is further included, and the air chamber is provided with a side edge branch, and the side edge branch is connected with the inlet end of the second electromagnetic ball valve, and the outlet end of the second electromagnetic ball valve is communicated with atmosphere;Gas pressure sensor and second hysteresis comparator are further included, and the gas pressure sensor is arranged in the side edge branch, and the control end of the gas pressure sensor is connected with one end of the second hysteresis comparator, and the other end of the second hysteresis comparator is connected with the second electromagnetic ball valve;Overflow valve is arranged between the accumulator group and the hydraulic oil tank. ​ ​ ​ ​ ​ ​

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