Wind turbine or water turbine comprising a hydraulic pump and motor

Abstract

The invention is a wind power plant (100) or micro wind power plant comprising a wind turbine (200) with a first rotary shaft (210), an alternator (700) suited to transform the rotary motion of a shaft into electrical energy, a hydraulic system suited to transmit the motion of said first rotary shaft (210) to said second shaft, wherein said hydraulic system in turn comprises: an open-circuit axial piston hydraulic pump (300), a hydraulic circuit (400) in which an oil flow driven by said hydraulic pump (300) circulates, a valve block (500) suited to control the oil flow, a hydraulic gear motor (600), a hydraulic oil tank (800).

Description

[0001] WIND TURBINE OR WATER TURBINE COMPRISING A HYDRAULIC PUMP AND MOTOR

[0002] DESCRIPTION

[0003] The present patent concerns wind power plants and hydroelectric power plants, and more preferably it concerns micro wind power plants, and in particular it includes a new electric power plant with improved operation for the generation of wind power or hydroelectric power.

[0004] Wind power plants are known, which comprise a wind turbine that is set rotating by the wind, and a generator that, connected to the turbine, converts mechanical energy into electrical energy. It is well known that wind power plants and micro wind power plants operate efficiently when the intensity of the wind is within a certain range, which leads to many limitations in their use.

[0005] Hydroelectric power plants are also known, in which a water flow hits a blade, in turn connected to a generator, which transforms mechanical energy into electrical energy. Hydroelectric power plants are usually very large and require a great difference between the height at which the water is fed into the turbine and the height at which the water is returned to the plant.

[0006] The main object of the present invention is to provide a small-sized power plant that is capable of generating electricity from renewable sources.

[0007] One of the objects of the new power plant is to ensure proper operation with any wind intensity and also to provide constant output voltage and frequency, which translates into constant energy.

[0008] The new electric power plant for generating power from renewable sources, and more preferably the new wind power plant or micro wind power plant or hydroelectric power plant, comprises: at least one wind turbine or at least one water mill with at least one first rotary shaft; an alternator suited to transform the rotary motion of a second shaft into electrical energy; a hydraulic system suited to transmit the motion of said first rotary shaft to said second shaft; and wherein said hydraulic system in turn comprises: an open-circuit axial piston hydraulic pump, wherein said pump is coupled with said first rotary shaft of said wind turbine; the torque and angular speed of the wind turbine or the water mill are then transformed into oil flow and pressure, generating a given hydraulic power; a valve block suited to control the oil flow driven by the hydraulic pump, wherein said flow is regulated in such a way as to keep the rotation speed of said alternator constant; a hydraulic gear motor with said second shaft connected to said alternator, wherein said hydraulic motor is set rotating by said oil flow; the hydraulic motor then converts hydraulic power into torque and rotational motion at a given speed of said second shaft connected to said alternator, which in turn will generate a given electrical power; a hydraulic oil tank which has a storage function and in which the oil is filtered to prevent the introduction of impurities into the hydraulic circuit, and in which any air present in the hydraulic circuit is eliminated.

[0009] More specifically, said hydraulic pump is coupled with said first shaft by means of mechanisms that multiply the number of revolutions of the wind turbine or the water mill.

[0010] Said valve block comprises at least two valves: a first proportional solenoid valve suited to regulate the rotation speed of the alternator; said first solenoid valve also has the function to stop the alternator in the case where the rotation speed of said wind turbine or water mill is above or below the set maximum and minimum limits; a second solenoid valve whose function is to force said hydraulic pump into maximum displacement in order to obtain the braking of said wind turbine or water mill in the case where the wind exceeds a set maximum value.

[0011] Said valve block also has a safety function, that is, the function to prevent overloads that would damage the hydraulic and mechanical components.

[0012] According to the invention, said oil tank can contain at least one temperature sensor intended to measure the oil temperature, wherein the measured value is used to manage the cooling system, for example by adjusting one or more cooling fans, which will then be activated according to the oil temperature, and to activate any alarms intended to signal too high or too low temperature values.

[0013] Furthermore, according to the invention, at least one heat exchanger having the function to dissipate the excess heat present in the hydraulic circuit is installed upstream of said tank.

[0014] Furthermore, according to the invention, said tank also contains at least one oil level sensor, and the plant is stopped if the measured level is below certain preset values. The operation of the system includes monitoring that can also be performed remotely, by means of applications installed on one or more electronic devices.

[0015] Monitoring involves checking the instant power generated by the plant, the energy produced daily and / or monthly and / or yearly and / or the total energy produced, the energy taken from the grid, and the energy consumed by the plant itself.

[0016] By assessing the monitored parameters, it will be possible to evaluate whether to integrate further components into the plant, for example an energy storage system.

[0017] In order for the plant to function properly, it is necessary that the number of revolutions to be transmitted to said hydraulic pump exceeds a given presettable minimum value, thus starting the plant. It is also necessary that the number of revolutions is below a presettable maximum value, above which the plant stops automatically to restart automatically only once the number of revolutions has fallen below said maximum limit value.

[0018] However, the plant can also be stopped manually, thus interrupting the operation of said alternator. In this case, essentially for safety reasons, the restart must also be controlled manually.

[0019] According to the invention, the plant can also be designed to stop in the event of a power failure, for example in the event of a fault or interruption in the power supply. In this case, it is possible to design the plant so that it restarts automatically as soon as the power supply is restored.

[0020] According to the invention, all the above-mentioned components, except for said wind turbine, are enclosed in a containment casing, on which a display showing the above- mentioned values and possibly a control interface can be mounted.

[0021] Said casing can conveniently be made of stainless steel.

[0022] Said wind turbine or said water mill is preferably but not necessarily made of polymethyl methacrylate (PMMA) and polycarbonate (PC).

[0023] In the case of a wind power plant, the plant configured as described above can operate with any wind intensity and ensure a constant voltage and frequency output, which translates into constant energy, thanks to the presence of said hydraulic pump and of said valve block connected to said alternator.

[0024] The plant, be it a wind power plant or a hydroelectric power plant, is easy to install thanks to its compact size and, if said wind turbine is a micro wind turbine, it can also be installed on the roof of buildings.

[0025] The characteristics of the new plant are better clarified in the following description, making reference to the drawings, which are attached by way of non-limiting example. Figure 1 shows a schematic three-dimensional view of the new wind power plant (100) when fully assembled, while Figure 2 shows a schematic view of the hydraulic system. The new wind power plant (100), in its embodiment illustrated in Figure 1 by way of example, comprises a wind turbine (200) with vertical axis, however the same inventive concept can be applied to any other type of wind turbine.

[0026] The turbine (200) is connected to a first rotary shaft (210).

[0027] The plant comprises an open-circuit axial piston hydraulic pump (300) and a hydraulic circuit (400) in which the oil flow driven by the pump circulates.

[0028] Said pump (300) is coupled with said first rotary shaft (210).

[0029] The plant also comprises a valve block (500) for controlling said oil flow, which in turn comprises: a first proportional solenoid valve suited to regulate the rotation speed of the alternator; a second solenoid valve whose function is to force said hydraulic pump into maximum displacement in order to obtain the braking of said wind turbine in the case where the wind exceeds a set maximum value.

[0030] Downstream of said valve block (500) there is a hydraulic gear motor (600) that is set rotating by said oil flow; the hydraulic motor then converts hydraulic power into torque and rotational motion at a given speed of a second shaft connected to an alternator (700), which in turn will generate a given electrical power.

[0031] The new plant (100) also comprises a hydraulic oil tank (800) which has a storage function and in which the oil is filtered to prevent the introduction of impurities into the hydraulic circuit, and in which any air present in the hydraulic circuit is eliminated. Said oil tank (800) contains at least one temperature sensor intended to measure the oil temperature, wherein the measured value is used to manage the cooling system, for example by adjusting one or more cooling fans, which will then be activated according to the oil temperature, and to activate any alarms intended to signal too high or too low temperature values.

[0032] Furthermore, according to the invention, at least one heat exchanger (900) having the function to dissipate the excess heat present in the hydraulic circuit is installed upstream of said tank (800).

[0033] Furthermore, according to the invention, said tank (800) also contains at least one oil level sensor, and the plant is stopped if the measured level is below certain preset values.

[0034] According to the invention, all the above-mentioned components, except for said wind turbine (200), are enclosed in a containment casing (120), on which a display showing the above-mentioned values and possibly a control interface can be mounted.

[0035] Figure 3 shows the new power plant (101) in the hydroelectric version in the case where said first rotary shaft (210), instead of being connected to the wind turbine (200), is connected to a water mill (201), that is, a device provided with blades (202) intended to be subjected to the thrusting action of a water flow. Figure 3 shows that, in that case, said first rotary shaft (210) is arranged horizontally, without however excluding other embodiments. Said hydroelectric power plant (101) must be integrated with a water management system which, for example, can comprise an upper reservoir or tank, at a higher position with respect to the water mill, and a second collection reservoir or tank at a lower position, in such a way that the flow generated by the difference in height between said upper tank and said collection tank can hit said water mill (201) and set it rotating.

[0036] According to the invention, it is also possible to make the water follow a closed circuit, including a pump for raising water from said collection tank to said upper tank. Therefore, with reference to the above description and the attached drawings, the following claims are made.

Claims

CLAIMS1. Power plant (100, 101) for the generation of power from renewable sources, comprising: at least one wind turbine (200) or at least one water mill no (201) with at least one first rotary shaft (210); an alternator (700) suited to transform the rotary motion of a second shaft into electrical energy; a hydraulic system suited to transmit the motion of said first rotary shaft (210) to said second shaft, characterized in that said hydraulic system in turn comprises: an open-circuit axial piston hydraulic pump (300), wherein said pump (300) is coupled with said first rotary shaft (210); a hydraulic circuit (400) in which an oil flow driven by said hydraulic pump (300) circulates; a valve block (500) suited to control the oil flow driven by the hydraulic pump, wherein said flow is regulated in such a way as to keep the rotation speed of said alternator (700) constant; a hydraulic gear motor (600) comprising said second shaft connected to said alternator (700), wherein said hydraulic motor is set rotating by said oil flow; a tank (800) suited to contain hydraulic oil.

2. Power plant (100, 101) according to claim 1, characterized in that said hydraulic pump (300) is coupled with said first shaft (210) by means of mechanisms which multiply the number of revolutions of said wind turbine (200) or said water mill (201).

3. Power plant (100, 101) according to claim 1, characterized in that said valve block (500) comprises at least one first proportional solenoid valve suited to regulate the rotation speed of said alternator (700).

4. Power plant (100, 101) according to claim 1, characterized in that said valve block (500) comprises at least one second solenoid valve whose function is to force said hydraulic pump into maximum displacement in order to obtain the braking of saidwater mill (201) or said wind turbine (200) in the case where the wind exceeds a set maximum value.

5. Power plant (100, 101) according to claim 1, characterized in that it comprises at least one temperature sensor located in said tank (800) and suited to measure the oil temperature, wherein the measured value is used to manage a cooling system.

6. Power plant (100, 101) according to claim 1, characterized in that it comprises at least one heat exchanger installed upstream of said tank (800) and having the function to dissipate the excess heat present in said hydraulic circuit (400).

7. Power plant (100, 101) according to claim 1, characterized in that it comprises at least one oil level sensor located in said tank (800), and wherein the plant is stopped if the measured level is below certain preset values.

8. Power plant (100, 101) according to the preceding claims, characterized in that it comprises a containment casing (120) suited to contain said alternator (700) and said hydraulic system, and wherein a display showing operating parameters and / or possibly a control interface is / are mounted on said casing (120).

9. Power plant (100, 101) according to any of the preceding claims, characterized in that it is a micro wind power plant, in which the axis of said wind turbine (200) is vertical.

10. Power plant (100, 101) according to any of the preceding claims, characterized in that it is a hydroelectric power plant, in which the axis of said water mill (201) is horizontal, and wherein said plant (101) comprises at least an upper tank, at a higher position with respect to the water mill, and a second collection reservoir or tank at a lower position, in such a way that the flow generated by the difference in height between said upper tank and said collection tank can hit said water mill (201) and set it rotating.

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