WO2014169699A1

WO2014169699A1 - A wave power generator set and method for generating electricity thereby

Info

Publication number: WO2014169699A1
Application number: PCT/CN2014/000365
Authority: WO
Inventors: Kwai-Shing POON; Shmoel Ovadia
Original assignee: EVERCO INTERNATIONAL GROUPS HOLDING Ltd
Current assignee: EVERCO INTERNATIONAL GROUPS HOLDING Ltd
Priority date: 2013-04-15
Filing date: 2014-04-02
Publication date: 2014-10-23
Anticipated expiration: 2015-10-15
Also published as: CN104100443A

Abstract

A wave power generator set, comprising: a wave energy gathering system (1), a hydraulic transmission system (2) and akinetic energy conversion system (3). Wave energy gathering system (1) comprises a wave gathering buoy (12) pivotally connected to the fixed engineering component (11). The hydraulic transmission system (2) comprises a leftover oil tank (21), a cylinder with piston (22) and a hydropneumatic accumulator (23). The cylinder with piston (22) is movably connected to the upper surface of the wave gathering buoy (12) at one end and secured to the fixed engineering component (11) at the other end. The leftover oil tank (21), the cylinder with piston (22) and the hydropneumatic accumulator (23) are connected by the input pipe (24) and the output pipe (25) respectively. Both input pipe (24) and output pipe (25) are equipped with a check valve (26). The kinetic energy conversion system (3) comprises hydraulic motor (31) and power generating equipment (32). The inlet port (311) of said hydraulic motor (31) is connected to the hydropneumatic accumulator (23) through the first pipe (4), and the outlet port (312) of said hydraulic motor (31) is connected to the leftover oil tank (21) through the second pipe (5).

Description

A wave power generator set and method for generating electricity thereby

TECHNICAL FIELD

The present invention relates to the field of power generation, particularly, to a low-loss and low-cost wave power generator set, and to a method for generating electricity employing this generator set.

BACKGROUND OF THE INVENTION

Every dynamic activity produces energy. Waves and sea currents as "natural renewable green energy" have long been used to generate electricity. There are a lot of existing theories and techniques, such as "tidal power, pendulor pump compression, floating device style, oscillating water column wave power" etc., and all of those are advanced skills. But in addition to the limitation with natural geographical conditions for development, the biggest drawback of these technologies is the high-cost. It is difficult to have these technologies to be implemented commercially.

Any "natural renewable green energy" is subjected to natural geographical environmental conditions. The key of invention and application is whether it is properly fit to the natural geographical environmental conditions, which determines the degree of limitation. Traditional "tidal power" is limited to low productivity by the twice daily tidal wave, and it needs places with a large tidal range (such as the Qiantang River mouth, etc.) to show its effectiveness. "Pendulor pump compression and floating device style" are suitable for power generation in the stable areas with enormous currents passing through, such as those open seas of Western Europe and Japan, in which power is generated by water pressure making use of narrowed pipes. But the construction costs of power generating equipments are high, and as the power generating equipments are located in the ocean for years, with sea water corrosion the equipments has short life-time, therefore the relative costs are very high. "Oscillating water column wave power" plant has huge power generating equipments built on the coastal land of the strong wave forces, such as Western Europe and Scandinavia. It is the world's most mature wave power generation technology, but due to the direct erosion of the waves, the maintenance costs as well as the extent and speed of damage are high, therefore the relative costs are also very high.

The main advantage of the "natural renewable energy" is environmental protection. But there are differences in the extent of environmental protection. For examples, the dam-type hydroelectric power plant will inevitably affect the regional environmental ecology; the wind power and solar power plants are naturally limited by wind type and sunlight, the annual effective power generation hours can hardly exceed 2,500 hours. As a result, it must occupy very large areas of land with low productivity; nuclear energy has potential danger of resulting in environmental pollution and radiation; the traditional coastwise oscillating water column wave power plant may also damage the coastal terrain.

The traditional concepts and technologies of power generation mentioned above must rely on the direct impact of the huge waves. Since most equipments are located outdoor or in water, they would be directly corroded by the huge waves and damaged quickly, therefore the costs are very high. In addition, they have more onerous requirements of water flow that ordinary wave cannot be utilized which causes great energy waste. To sum up the above, the inevitable trend of the development of natural renewable green energy is to seek a means for electricity generation with indoor main power generating equipment, which would not be subjected to the wave corrosion directly and could make use of the wave effectively.

SUMMARY OF THE INVENTION

In order to solve the above-mentioned technical issues, the present invention provides a low-cost wave power generator set which is easy to be implemented commercially.

To achieve the object of the invention described above, the present invention provides the following technical solutions:

A wave power generator set, comprising: a wave energy gathering system, a hydraulic transmission system and a kinetic energy conversion system,

said wave energy gathering system comprises a fixed engineering component and a wave gathering buoy, said wave gathering buoy is pivotally connected to the fixed engineering component at one end;

said hydraulic transmission system comprises a leftover oil tank, a cylinder with piston and a hydropneumatic accumulator; the cylinder with piston is movably connected to the upper surface of the wave gathering buoy at one end and secured to the fixed engineering component at the other end; said leftover oil tank and cylinder with piston are connected by the input pipe; said cylinder with piston and hydropneumatic accumulator are connected by the output pipe; both said input pipe and output pipe are equipped with a check valve that avoids the oil returning toward the leftover oil tank;

said kinetic energy conversion system comprises a hydraulic motor and a power generating equipment connected to the hydraulic motor; the inlet port of said hydraulic motor is connected to the hydropneumatic accumulator through the first pipe, and the outlet port of said hydraulic motor is connected to the leftover oil tank through the second pipe.

Furthermore, said wave gathering buoy is of a hollow box-type structure with a tilting front end, and the upper edge of the front end is closer to the oncoming waves than the lower edge.

Furthermore, the rear end of said wave gathering buoy is at least equipped with a pair of parallel arms, and said arms are pivotally connected to the fixed engineering component.

Furthermore, said first pipe is also equipped with an oil replenishing pipe, and the other end of said oil replenishing pipe is connected to and communicated with the leftover oil tank;

said hydraulic motor is also equipped with an oil return port, and said oil return port is connected to and communicated with the leftover oil tank through a pipe.

Furthermore, said wave energy gathering system comprises a variety of wave gathering buoys arranged in parallel.

Furthermore, said wave energy gathering system comprises a set of wave gathering buoy group or multiple sets of wave gathering buoy group arranged in parallel; said wave gathering buoy group(s) comprises a variety of wave gathering buoys sequentially connected by joint-rings; the rear end of said first wave gathering buoy is movably connected to the fixed engineering component, a cylinder with piston is provided between two adjacent wave gathering buoys, said cylinder with piston is connected to the output pipe and the input pipe respectively through pipes. Furthermore, said wave gathering buoy group comprises two or three wave gathering buoys sequentially connected by joint-rings.

Furthermore, each of the said wave gathering buoy is equipped with a safe rod and a stationary ring.

Furthermore, said wave gathering buoy is equipped with an air pressure drainage device.

Furthermore, said hydropneumatic accumulator comprises a variety of small hydropneumatic accumulators; said small hydropneumatic accumulator is divided into an oil accumulative section and a gas pressure section by a major piston; said oil accumulative section is connected to and communicated with an output pipe and the first pipe; said gas pressure section is filled with gas that does not react with the oil.

Furthermore, said hydraulic transmission system further comprises a hydraulic control system, a check valve and a distributary pipe used to control the oil flow and pressure; said distributary pipe is connected to and communicated with the leftover oil tank.

Furthermore, said hydraulic transmission system further comprises a pressure pump directly transporting the oil to the first pipe from the leftover oil tank.

Furthermore, said second pipe is equipped with a filter.

Furthermore, said power generating equipment is equipped with an inertia flywheel.

Furthermore, comprising backup generator equipment, said backup generator equipment connected to the generator.

Furthermore, said fixed engineering component is a sea pole that is rotatable and/or movable up and down. Furthermore, said fixed engineering component is a column on the sea bottom arranged in the open sea.

Furthermore, said fixed engineering component is a cliff rock or artificial dyke.

Furthermore, both said input pipe and output pipe are equipped with corresponding approaching bridges.

A power generating method employing the wave power generator set, comprising following steps:

Step 1 : waves rising gradually to the crest, pushing the wave gathering buoys, causing the wave gathering buoys to rotate about the fixed engineering component, driving the cylinder with piston, and oil within the cylinder with piston being drained to the hydropneumatic accumulator through the output pipe;

Step 2: waves falling from the crest, the wave gathering buoys returning gradually, driving the cylinder with piston to transport the oil into the cylinder with piston from the input pipe;

Step 3: waves being produced recurrently, driving the wave gathering buoys to move along with the waves, transporting the oil into the hydropneumatic accumulator continuously;

Step 4: the oil within the hydropneumatic accumulator increasing, the pressure within the gas pressure section increasing to the limit value, the gas pressure section driving the major piston to extrude the oil out from the hydropneumatic accumulator;

Step 5: the oil extruded from the hydropneumatic accumulator being extruded to the hydraulic motor through the first pipe, the hydraulic motor driving the power generating equipment to generate electricity.

Repeating step 1 to step 5 to generate electricity continuously. Furthermore, the above method also comprises:

Step 6: the oil returning to the leftover oil tank through the second pipe after passing the hydraulic motor.

Furthermore, when the wave is larger and the oil transporting exceeds the demand of the hydraulic motor, the excess oil is transported to the leftover oil tank through the distributary pipe; when the wave is smaller and the oil transporting cannot meet the demand of the hydraulic motor, the leftover oil tank replenishment transports the oil to the hydraulic motor through the distributary pipe to ensure the operation of the hydraulic motor.

Furthermore, the oil within said output pipe is transported in pinball-style.

The following advantages may be achieved by the technical solutions provided by the present invention:

(1) Except the wave gathering buoy and sea pole needing to be located offshore, other equipments of the equipment main body may be located in the indoor plant. The hydraulic system is used to transport the wave energy to the main equipment within onshore plant, avoiding the wave erosion and the loss being lowered during usage.

(2) The present invention may utilize wave to realize electricity generation. It realizes electricity generation by utilizing natural energy effectively, thereby the costs being lowered.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a schematic structural view of the present invention;

Figure 2 is a schematic structural view of a wave energy gathering system of the present invention; Figure 3 is a schematic structural view of a wave energy gathering system of the present invention;

Figure 4 is a schematic structural view of a wave energy gathering system of the present invention;

Figure 5 is a schematic structural view of a hydraulic transmission system of the present invention;

Figure 6 is a schematic structural view of a leftover oil tank of the present invention;

Figure 7 is a schematic structural view of a kinetic energy conversion system of the present invention;

Figure 8 is a schematic view of an embodiment of the present invention;

Figure 9 is a schematic view of another embodiment of the present invention;

Figure 10 is a schematic view of another embodiment of the present invention;

Figure 11 is a schematic view of another embodiment of the present invention;

Figure 12 is a schematic view of another embodiment of the present invention.

Wherein:

I wave energy gathering system,

I I fixed engineering component,

I I I sea pole,

12 wave gathering buoy, arm,

safe rod,

stationary ring,

hydraulic transmission system, leftover oil tank,

cap of oil tank,

cylinder with piston,

hydropneumatic accumulator, oil accumulative section, gas pressure section,

major piston,

air pressure gauge,

input pipe,

output pipe,

check valve,

oil replenishing pipe,

distributary pipe,

filter,

kinetic energy conversion system, hydraulic motor,

inlet port,

outlet port,

oil return port,

power generating equipment, 321 emergency manual switch,

322 control instrument,

323 voltage instrument,

34 pressure pump,

4 first pipe,

41 hydraulic instrument,

5 second pipe,

6 approaching bridge,

7 regulator.

DETAILED DESCRIPTION OF EMBODIMENTS

For clearly understanding the object, technical solutions and advantages of the present invention, the present invention will be further described in detail in connection with figures and embodiments. It is to be understood that the specific embodiments illustrated herein are intended for the purpose of illustration only and are not intended to limit the present invention.

FIG. 1 is a schematic structural view of the present invention. The wave power generator set shown in FIG. 1 comprises a wave energy gathering system 1, a hydraulic transmission system 2, and a kinetic energy conversion system 3. Said wave energy gathering system 1 comprises a fixed engineering component 11 and a wave gathering buoy 12. Said wave gathering buoy 12 is pivotally connected to the fixed engineering component 11 at one end. Said hydraulic transmission system 2 comprises a leftover oil tank 21, a cylinder with piston 22, and a hydropneumatic accumulator 23. Said cylinder with piston 22 is movably connected to the upper surface of the wave gathering buoy 12 at one end and secured to the fixed engineering component 11 at the other end. Said leftover oil tank 21 and cylinder with piston 22 are connected to each other by the input pipe 24. Said cylinder with piston 22 and hydropneumatic accumulator 23 are connected by the output pipe 25. Both said input pipe 24 and output pipe 25 are equipped with a check valve 26 avoiding the oil returning to the leftover oil tank 21. Said kinetic energy conversion system 3 comprises a hydraulic motor 31 and a power generating equipment 32 connected to the hydraulic motor 31. The inlet port 311 of said hydraulic motor 31 is connected to the hydropneumatic accumulator 23 through the first pipe 4. The outlet port 312 of said hydraulic motor is connected to the leftover oil tank 21 through the second pipe 5. The main components of the overall wave power generator set employs the mechanical operation of "wave gathering buoys" that going with the natural floating of the wave. It thus has absolutely no adverse effects on the natural environment. There are also no emissions, no waste, no sewage, no radiation, and no noise. Especially, the floating of a set of buoys may activate the sea water and improve the living environment for fishes and other sea creatures. Another particular advantage is that the dancing "wave gathering buoys" is an innovative landscape, which can be used for developing into a tourism resource.

The geography basis of the present invention is that the wave is based on the circular motion of the seawater elements. There are many reasons for producing the circular motion of the seawater elements, among which the most notable one is the "storm", in which the wind compresses seawater for directed activities to produce "progressive wave". The earlier stage of the progressive wave is the swell whose crest is very low. The higher the crest of the wave propelled by squeezing becomes, the shorter the wave length becomes. When the ratio of crest to wave length becomes 1 : 1, the crest may break, which is known as the "broken waves", and that is the "white horses" generally known. The case of "wave type" changing from the swell to the broken wave is relatively influenced by wind, wind direction, and coastal terrain. Therefore, it produces different wave types in the open sea, gentle slope or sea cliff terrain. This directly determines the power of the set of wave power generation technology.

The saying goes that "there are waves three feet high even if there is no wind". Although it is a bit exaggerated, it is true that the wave exists indeed when there is no wind, such as the daily tidal phenomenon that the ebb and flow of the sea surface also causes seawater to float. The extent of the tidal range depends on the tidal time, tide direction and coastal terrain. As a result of Earth's rotation, the activities of the seawater in the Northern Hemisphere have certain northeast deflecting force which is obviously shown in the completely windless state. But, in general, the northeast deflecting force works together with the storms and direction of tide, especially the world-famous Kuroshio and Gulf Stream are formed by the northeast deflecting force and the prevailing westerly winds. And in the coast of South China Sea and East China Sea, the formation of the coastal current is also of the same reason, which is known as the invisible waves. Though the kinetic energy of the invisible wave is not too great, it is sufficient to make a set of buoys to float and to be the renewable energy which may be used by the present invention. There is a sea-land breeze in micro-climatology which is due to the difference in the degree of daily heat absorption and cooling between land and sea. It makes partial of local breeze to change, resulting in a small coastal wave, which will boost the buoys' floating functions. In addition, the differences in nature between the sea surface and seabed, including the depth, seawater temperature difference, density, salinity, etc. cause the vertical movement of seawater elements, resulting in a vibration wave. The deeper the water, the more obvious it is. However, since the set of wave gathering buoys are only provided at a place located in the depth of several meters, it would hardly be affected.

The wave power generator set provided by the present invention further comprises a kinetic energy conversion system of the leftover oil tank 21 as shown in FIG. 6. The leftover oil tank 21 is another key component of the present invention which replenishes the hydraulic oil and directs the supply-output cycle of the oil. It is connected to the cylinder with piston 22, the hydropneumatic accumulator 23, the hydraulic control system and the hydraulic motor 31 respectively. A cap 211 is provided on the leftover oil tank. Any excess oil will return to the leftover oil tank 21 from the hydraulic control system and the hydraulic motor 31. The oil will return from the leftover oil tank back to the cylinder with piston connected to the buoy via the hydraulic leftover pipe (input pipe) 24 of the hydropneumatic accumulator for the cyclic movement of another wave period.

In addition to a filter 29 associated with the hydraulic motor 31 for ensuring the good quality of oil, most importantly, the leftover oil tank 21 is provided with a pressure pump 34 which is the device of automatic emergency protection and safety system. The pressure pump (34) is initiated automatically to drive the oil within the leftover oil tank and to continue the operation of electricity generation in the case of the oil transfer system operating abnormally due to sea wave.

FIG. 2 is a schematic structural view of a wave energy gathering system of the present invention. As shown in FIG. 2, said wave gathering buoy 12 has a hollow box-type structure being substantially sealed. Thin steel is preferably selected as its manufacturing material. Its front end tilts, and the upper edge of the front end is closer to the oncoming waves than the lower edge. The wave gathering buoy is a large equipment that could undulate following the waves. Its floating index depends on the wave type and the pattern of the wave gathering buoy, that is to say, the basic index coefficients had been recorded by the energy are obviously relevant to the height and frequencies of wave. An air pressure drainage device is provided in said wave gathering buoy. In case of in-leakage of seawater into the empty tank of the wave gathering buoy, a particularly configured air pressure drainage tube will drain the water out immediately in order to maintain the biggest floating force of the wave gathering buoy. The rear end of said wave gathering buoy 12 is at least equipped with a pair of parallel arms 13, and said arms 13 are pivotally connected to the fixed engineering component 11. The expansion arms (arms) at the rear end of the wave gathering buoy are connected to the sea pole through the fulcrum by fixed bolt shaft. This makes the front end of the wave gathering buoy body may undulate following the waves, and float up and down complying with the crests and troughs of waves to produce continuous kinetic energy. Two sets of cylinder with piston 22 are preferably equipped on the wave gathering buoy to cooperate with the rising and falling cyclic motion of the wave gathering buoy 12. When the wave crest is arriving, the wave gathering buoy 12 is raised by the progressive wave, the rising set of cylinder with piston is pressured, and the oil is then outputted immediately as the marble principle through its output pipe 25 from the other end, which is time-effective while reducing friction loss. At the same time, some oil returns to the falling set of cylinder with piston from the leftover oil tank. When the wave gathering buoy is falling from the wave crest, it will generate the undertow. The falling set of cylinder with piston is pressured, and the oil is outputted through its hydraulic output pipe. At the same time, some oil returns to the rising set of cylinder with piston from the leftover oil tank 21. Therefore, the wave gathering buoy floats up and down, the oil cycles continuously through two sets of cylinder with piston 22 to produce continuous kinetic energy. Since the pressure of the progressive wave is stronger than that of the undertow, the size of the rising set of cylinder with piston is larger than that of the falling set of cylinder with piston.

FIG. 3 is a schematic structural view of another wave energy gathering system of the present invention. As shown in FIG. 3, the wave energy gathering system comprises multiple wave gathering buoys 12 arranged in parallel. It makes use of the multiple wave gathering buoys and cylinder with pistons system to collect wave energy resources and to cooperate with a large generator set. Therefore, there may be two types of spatial layout of the wave gathering buoys: one is the type of series along the coast (shown in FIG 3.) which may last a few kilometers continuously; while the other is the wave energy gathering system shown in FIG. 4, comprising a set of wave gathering buoys group or multiple sets of wave gathering buoys group arranged in parallel; said wave gathering buoys group comprises multiple wave gathering buoys sequentially connected by joint-rings; the rear end of said first wave gathering buoy is movably connected to the fixed engineering component; a cylinder with piston is arranged between two adjacent wave gathering buoys; said cylinder with piston 22 is connected to the output pipe 25 and the input pipe 24 respectively through pipes. This structure is the interlink type in the open sea, wherein each link may be preferably configured with two or three wave gathering buoys depending on swell condition on the sea. In other words, under the best natural geographic conditions, the spatial layout of the wave gathering buoys may be a glorious planar scenery. FIG. 5 is a schematic structural view of a hydraulic transmission system of the present invention. As shown in FIG.5, the rising and falling cyclic motions of the wave gathering buoy transport the wave kinetic energy to the hydropneumatic accumulator within the plant through the hydraulic output pipe (the output pipe). The oil transmission is not in fluid type because of the sealing design of the output pipe. When one end is pressured, oil is outputted immediately from the other end like a marble. A check valve 26 is arranged between the output pipe and the hydropneumatic accumulator to avoid the return of oil.

The hydropneumatic accumulator is one of the key components of the present invention. To comply with the differences in geographical conditions, a few pieces of wave gathering buoys may be used to connect to one generator set at the same time. So the hydropneumatic accumulator is an entirety containing several small entities of pneumatic pressure tanks (small hydropneumatic accumulators), that means said hydropneumatic accumulator comprises multiple small hydropneumatic accumulators. Each pneumatic pressure tank (small hydropneumatic accumulator) is entirely sealed. Said small hydropneumatic accumulator is divided into the oil accumulative section 231 and the gas pressure section 232 by the major piston 233. Said oil accumulative section 231 is connected to and communicated with the output pipe 25 and the first pipe 4. Said gas pressure section 232 is filled with gas (preferably nitrogen) which does not react with the oil. When the oil is inputted through several hydraulic output pipes (output pipes), the oil accumulative section 231 only has accumulative actions and waits for the energy conversion. Due to this accumulative function, as long as the wave gathering buoys lightly float, the combined energy of the wave energy collected by a few pieces of buoys is great, and no surging wave is needed. When the oil in the oil accumulative section is increasing, it advances to the gas pressure section to squeeze the high pressure gas within the section. Substantially, nitrogen is a cheap and stable natural gas, and it does not resist (which means it does not react with) the hydraulic oil. However, when the pressure space of nitrogen is reaching a certain limit, rebound may occur such that the automatic regulating major piston is initiated to inject oil into the hydraulic control system from the hydropneumatic accumulator. When the oil in the oil accumulative section is decreasing, the major piston returns to its original position automatically.

The hydraulic control system mainly comprises check valve 26 and regulator 7 that are tying in with the wave cycle, and it is controlled by a hydraulic instrument 41. The wave cycle refers to the wave frequency, usually there are 6 to 10 times per minute. It is adjusted and controlled to the appropriate time according to the wave types. When the timing is appropriate, the wave cycle valve opens to supply oil to the hydraulic motor.

FIG. 7 is a schematic structural view of a kinetic energy conversion system of the present invention. As shown in FIG. 7, the kinetic energy conversion system is also equipped with a control device comprising emergency manual switch 321, control instrument 322 and voltage instrument 323. When the hydraulic control system is in cyclic action, oil is supplied to the hydraulic motor normally, and the hydraulic motor is launched such that the connected generator may run for electricity production. Said generator is configured with an inertia flywheel, which means the turbine of generator is coordinated with the inertia flywheel. Therefore, the subsequent power neither needs to be very strong nor to be the same that the generator is still able to produce stable power in operation. So, the hydraulic motor should not stop. However, in the case that the oil supplied from the hydropneumatic accumulator may be insufficient due to the temporary low wave, an automatic emergency oil replenishing system will supply oil from the leftover oil tank in order to keep the hydraulic motor in a normal running condition. If any excess oil enters the hydraulic motor, the small hydraulic pipes draw the excess oil from the oil return port back to the leftover oil tank to keep the hydraulic motor operating condition stable.

The kinetic energy conversion system further comprises backup generator equipment connected to the generator. When the wave gathering buoy suspends its activities for a short period of time, like a couple of days, such as due to typhoon or calm wind, the backup manual generating mechanism of the system maintains the low electricity production in generation. The generator set is of a common model with no special device. Electricity voltage meter and electronic control meter are provided as usual. The power produced is outputted to the transformer or grid system by an electricity output device.

FIG. 8 is a schematic view of an embodiment of the present invention. As shown in FIG. 8, an advantage of the present invention is that most parts of the equipment of this invention are placed in a plant on coastal land only except the wave gathering buoys 12 are on the sea. The buoy 12 preferably used is at a length of approximately five meters with an arm 13 of about one meter, so it should be at least six meters deep from the sea level for the floating device. There are two feasible types of marine engineering works: one is the dyke-based construction as shown in FIG. 8, which means the marine engineering works of the present invention could be built on the natural sea cliff, artificial dyke or seawall with deeper sea depth. That is to say, said fixed engineering component is cliff rock or artificial dyke. The wave gathering buoy is directly hanged on the platform made up of reinforced concrete built on the cliff rock or along the dyke, and it is connected to the leftover oil tank and the hydropneumatic accumulator within the coastal plant by the hydraulic pipes (input pipes and output pipes). Since the oil is transported in pinball-style, the length of output pipes will not affect the transmission function.

Another is the buoy construction of sea pole as shown in FIG. 9 which is suitable to be constructed on the sandy coast and could build a series of offshore piles platform. It utilizes the approaching bridge to connect the output pipes and the input pipes to the leftover oil tank and the hydropneumatic accumulator within the coastal plant. Since the oil is transported in pinball-style, the length of hydraulic pipes will not affect the transmission function. Professional engineering unit is responsible for the design and construction of marine engineering of sea poles. Since the sea poles are not heavy as they only contain the hanging buckles of the set of wave gathering buoys and do not have a platform, the bearing force and pullout force against the sea poles are very slight. However, the aspects of twisting and breaking must be in accordance with the environmental currents requirements with the principle of being safe and durably practical. Most of the marine engineering of sea poles is located one hundred to two hundred meters off the shore, depending on the seabed topography and geology. The depth of the poles that placed into the bedrock on the seabed also depends on the seabed topography and geology. The professional design of the preferred sea pole 111 has a major column and one or two raked poles attached to the lower part for fixing. The device in the upper part of the major column of the wave gathering buoy is jacketed with an adjustable steel sleeve to cope with the tidal range and change of wind direction. That is to say, said fixed engineering component is a sea pole 111 which is rotatable and/or movable up and down.

As shown in FIG. 10, a major column movable up and down may also be selected as the fixed engineering component. The tidal phenomenon changes regularly every day. Its regularity is significant, so it is easy to control the relative relationship between the buoys and the tidal surface during the ebb and flow of tides. Buoys are generally arranged on the mean sea level. However, in a place with a larger tidal range, a floating desktop or an electronic instrument can be used to operate the function of the up and down activities of the steel sleeve of the major column. That is of the common truth that when the water rises, the boats float high accordingly.

As shown in FIG. 11 , the fixed engineering component may also be provided as a rotatable sea pole that may be adjusted according to the wind direction. Due to wave type is influenced by the wind directions, and the generation capacity is influenced by the wave type, the maximum capacity is outputted when the wave gathering buoy is set into a windward position with the highest wave height. China is under the influence of monsoon climate. The wind direction in the winter is contrary to that of the summer. There is northeasterly in the winter while southerly in the summer. Wind direction in different places and seasons are also slightly different. Therefore it can also use the electronic equipment to operate the semi-circular rotation of the steel pipes of the major column to cope with the seasonal changes of wind direction for the best performance.

As shown in FIG. 12, said buoy is equipped with a safe rod 14 and a retrieving stationary ring 15 respectively. The typhoon is the most serious disaster to the present invention. In this invention, the wave gathering buoys are the only equipments exposed to the sea. A coupling device operated by an electronic instrument is designed and equipped on the wave gathering buoys to separate its front end from sea water. It is then anchored (by the safe rod to avoid damaging the buoys) on the major column or the platform in order to minimize the damage.

In conclusion, the body of water-land-based wave energy conversion system in the wave power generator set provided by the present invention is specifically the engineering works of the platform on sea cliff or dyke, or the engineering works of the column at the sea bottom as the fixed engineering components. The wave gathering buoys are coupled with the fixed engineering components and centered on the axis in the vertical plane of the fixed component. There is at least one cylinder with piston to transport the hydraulic oil. When the piston extends and retracts, the cylinder with piston connects to the fixed engineering components at one end and couples to the wave gathering buoy at the other end. The leftover oil tank performs the function of maintaining the kinetic energy.

In the wave energy gathering system, the coupling components of buoy comprise at least a pair of parallel arms, by which the wave gathering buoy is connected to the fixed engineering components. Each of the arms intersects with the fixed engineering components in a vertical plane. The length of the sections of the parallel arms linking to a set of wave gathering buoy are approximately equal such that the set of buoy has circle type of free activities. The front end of the buoy tilts in such a manner that its upper edge is closer to the oncoming waves than the lower edge so that the buoy is easier to be set off by the wave peak. An air pressure drainage device arranged in the buoy keeps the sealed hollow box-type device in the buoy at its best function of floating. A hydraulic piping system comprises at least a set of hydropneumatic accumulator. The hydraulic pipes link the wave gathering buoy with the wave energy transmission system. The hydraulic gathering system comprises at least two hydraulic oil pipes. The first one (the output pipe) appears at the wave crest when the piston contracts to set pressure to direct the oil to the oil accumulative section in the large hydropneumatic accumulator, while the other one (the input pipe) appears at the wave trough when the piston stretches to release pressure to direct the oil back.

The hydraulic system is equipped with a hydropneumatic accumulator to receive the input of the hydraulic oil from the cylinder with piston in order to supply for the motivation of the hydraulic motor, and to output the hydraulic oil to the cylinder with piston to achieve the cycle system function. The hydraulic transmission system is equipped with the one-directional valve (the check valve) or the switch control valve at different level of pressure to control the hydraulic oil for determining the quantity needed and making it function at the desired direction. The hydraulic transmission system (the first pipe) is equipped with the control valves and the regulator which could control and regulate the hydraulic pressure and to drain the excess hydraulic oil from the system to the leftover oil tank. The hydraulic system is equipped with a leftover oil tank, in which the hydraulic oil returns from the hydraulic motor to the cylinder with piston for revolving use.

The gas pressure section of the large hydropneumatic accumulator contains stable gases. Whenever the gas is under hydraulic pressure up to a certain level, a force will be created to press the hydraulic oil in the oil accumulative section to actuate the hydraulic motor. The gas pressure section of the large hydropneumatic accumulator is equipped with a pneumatic gas meter to check the volume of the gas and its air pressure condition. In the wave energy conversion system, in order to protect the equipments from the pounding of waves and corrosion, the vast majority of equipments are placed in the onshore power plant. The cylinder with piston and the oil transmission pipes are equipped with the check valves to control the oil flow and pressure, especially to prevent the anomaly of the hydraulic oil made by the cylinder with piston due to the sudden significant changes of wave types. Inside the large hydropneumatic accumulator, the quieter nitrogen is in the upper portion while the hydraulic oil is in the lower portion. The strength of the waves is monitored by an electronic device in order to study the smaller wave energy being able to respond to the larger power generation.

In the wave energy gathering system, the natural geographic conditions such as wind direction, wind speed and coastal landscape are the basic elements to determine the wave types, and the height and frequency of different types of waves affect the electricity productivity. The present invention had been experimented yearly in the Mediterranean climatic region with no wave in July and August but strong wave in December, resulted in a set of experimental data showing the parameters of wave types and electricity (as shown in table 1) which is the basis for establishing the wave power plants.

Table 1 Parameters of wave types and electricity

As shown in Table 1, the settings of the wave power generator set provided by the present invention are required to cooperate with the geographical conditions. The fixed engineering component is positioned on the natural sea cliff, artificial dyke or seawall depending on various geographical conditions. "Sea bottom columns" may also be constructed in the open sea so as to arrange the wave gathering buoys on the sea bottom columns. In each case, as long as the water depth reaches 4 meters or above and the wave height in four seasons is above 1.0 meter, it may basically achieve the electricity generation index and the normal effective function. By way of example, with 6-7 waves per minute as commonly seen and wave height of about 1.5 meters, the electricity produced per meter (of wave width) is 30kWh. As each buoy is at a width of 3.5 meters, the produced electricity of each buoy is about 30x3.5-100 kilowatt-hours (kWh). Three parallel wave gathering buoys can produce electricity up to 300 kilowatt-hours.

The power generating method employing the wave power generator set described above comprises the following steps:

Step 1 : waves rising gradually to the crest, pushing the wave gathering buoys, causing the wave gathering buoys to rotate about the fixed engineering component, driving the cylinder with piston, oil within the cylinder with piston being drained to the hydropneumatic accumulator through the output pipe;

Step 5: the oil extruded from the hydropneumatic accumulator being extruded to the hydraulic motor through the first pipe, the hydraulic motor driving the power generating equipment to generate electricity;

Step 6: the oil returning to the leftover oil tank through the second pipe after passing the hydraulic motor;

Step 7: repeating step 1 to step 6 to generate electricity continuously.

When the wave is larger and the oil transporting exceeds the demand of the hydraulic motor, the excess oil is transported to the leftover oil tank through the distributary pipe; when the wave is smaller and the oil transporting cannot meet the demand of the hydraulic motor, the leftover oil tank replenishment transports the oil to the hydraulic motor through the distributary pipe to ensure the normal operation of the hydraulic motor.

The embodiments described above merely illustrate the description of the present invention. Although the description is comparatively specific and detailed, it could not be construed as the limit to the scope of the present invention. It should be understood that the ordinary persons skilled in the art may, without departing from the scope and the idea of the present invention, also make certain modifications and improvements, all of which are also within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be subject to the appended claims.

Claims

Claims:

1. A wave power generator set, comprising: a wave energy gathering system, a hydraulic transmission system and a kinetic energy conversion system;

said wave energy gathering system comprises a fixed engineering component and a wave gathering buoy, wherein said wave gathering buoy is pivotally connected to the fixed engineering component at one end; said hydraulic transmission system comprises a leftover oil tank, a cylinder with piston and a hydropneumatic accumulator. The cylinder with piston is movably connected to the upper surface of the wave gathering buoy at one end and secured to the fixed engineering component at the other end; said leftover oil tank and cylinder with piston are connected by the input pipe; said cylinder with piston and hydropneumatic accumulator are connected by the output pipe; both said input pipe and output pipe are equipped with a check valve that avoids the oil returning toward the leftover oil tank;

2. The wave power generator set according to claim 1, wherein said wave gathering buoy is of a hollow box-type structure with a tilting front end, and the upper edge of the front end is closer to the oncoming waves than the lower edge.

3. The wave power generator set according to claim 1 or 2, wherein the rear end of said wave gathering buoy is at least equipped with a pair of parallel arms, and said arms are pivotally connected to the fixed engineering component.

4. The wave power generator set according to claim 1, wherein:

said first pipe is further equipped with an oil replenishing pipe, and the other end of said oil replenishing pipe is connected to and communicated with the leftover oil tank;

5. The wave power generator set according to claim 1 or 2, wherein said wave energy gathering system comprises a variety of wave gathering buoys arranged in parallel.

6. The wave power generator set according to claim 1 or 2, wherein said wave energy gathering system comprises a set of wave gathering buoy group or multiple sets of wave gathering buoy group arranged in parallel; said wave gathering buoy group(s) comprises a variety of wave gathering buoys sequentially connected by joint-rings; the rear end of said first wave gathering buoy is movably connected to the fixed engineering component, a cylinder with piston is provided between two adjacent wave gathering buoys, said cylinder with piston is connected to the output pipe and the input pipe respectively through pipes.

7. The wave power generator set according to claim 6, wherein said wave gathering buoy group comprises two or three wave gathering buoys sequentially connected by joint-rings.

8. The wave power generator set according to claim 1, wherein each of the said wave gathering buoy is equipped with a safe rod and a stationary ring.

9. The wave power generator set according to claim 1, wherein said wave gathering buoy is equipped with an air pressure drainage device.

10. The wave power generator set according to claim 1, wherein said hydropneumatic accumulator comprises a variety of small hydropneumatic accumulators; said small hydropneumatic accumulator is divided into an oil accumulative section and a gas pressure section by a major piston; said oil accumulative section is connected to and communicated with an output pipe and the first pipe; said gas pressure section is filled with gas that does not react with the oil.

11. The wave power generator set according to claim 1 , wherein said hydraulic transmission system further comprises a hydraulic control system, a check valve and a distributary pipe used to control the oil flow and pressure; said distributary pipe is connected to and communicated with the leftover oil tank.

12. The wave power generator set according to claim 1, wherein said hydraulic transmission system further comprises a pressure pump directly transporting the oil to the first pipe from the leftover oil tank.

13. The wave power generator set according to claim 1, wherein said second pipe is equipped with a filter.

14. The wave power generator set according to claim 1, wherein said power generating equipment is equipped with an inertia flywheel.

15. The wave power generator set according to claim 1, further comprising a backup generator connected to the generator.

16. The wave power generator set according to claim 1, wherein said fixed engineering component is a sea pole that is rotatable and/or movable up and down.

17. The wave power generator set according to claim 1, wherein said fixed engineering component is a column on the sea bottom arranged in the open sea.

18. The wave power generator set according to claim 1, wherein said fixed engineering component is a cliff rock or artificial dyke.

19. The wave power generator set according to claim 1, wherein both said input pipe and output pipe are equipped with corresponding approaching bridges.

20. A power generating method employing any one of the wave power generators sets of the preceding claims, comprising the following steps of:

21. The electricity generating method according to claim 20, wherein repeating step 1 to step 5 to generate electricity continuously.

22. The electricity generating method according to claim 20, further comprising:

23. The electricity generating method according to claim 20, wherein when the wave is larger and the oil transporting exceeds the demand of the hydraulic motor, the excess oil is transported to the leftover oil tank through the distributary pipe; when the wave is smaller and the oil transporting cannot meet the demand of the hydraulic motor, the leftover oil tank replenishment transports the oil to the hydraulic motor through the distributary pipe to ensure the operation of the hydraulic motor.

24. The electricity generating method according to claim 20, wherein the oil within said output pipe is transported in pinball- style.