Fluid power generation system, control device, and method of control

Abstract

To provide a technology of novel fluid power generation without actively rotating a rotor.SOLUTION: A fluid power generation system 10 includes: a rotor 12 rotatable with a fluid; a rotary electric machine 14 including a rotator that is configured to rotate with the rotor 12; and a controller 16 for performing vector control of the rotary electric machine 14 so as to make a rotation index value indicating a rotational speed or rotational frequency of the rotary electric machine 14 with the rotation of the rotor 12 become zero or a rotational frequency of a rotor 12 become or close to a prescribed rotation target value equivalent to a prescribed frequency of 1 Hz or less.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a fluid power generation system that converts the kinetic energy of a fluid into electric power. [Background technology]

[0002] Conventional fluid generators, which convert the kinetic energy of a fluid into electricity, rotate a rotating body that can be rotated by the fluid by exposing it to a fluid in motion, and then convert the rotational energy into electrical energy using a generator (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-070516 A Summary of the Invention [Problem to be solved by the invention]

[0004] As a fluid power generator that utilizes wind, a propeller-type wind power generator equipped with three blades on a horizontal axis as a rotating body is widely used (see, for example, Patent Document 1). A propeller-type wind power generator has a higher power coefficient (blade conversion efficiency) and a circumferential speed ratio than other types of wind power generators, and is considered to be advantageous for generating electricity efficiently when installed in windy places. However, in order to increase the amount of electricity generated by a propeller-type wind power generator, the blade rotation area needs to be large, and it inevitably becomes a large and heavy object. Therefore, a solid foundation that can secure a large space and where the wind blows relatively fast is required. Therefore, there is a problem that the installation site is limited. One of the particularly problematic points is the rotation of the rotating body that rotates by the fluid. Specifically, the rotation of the rotating body causes problems such as noise, scattering and safety problems when the blades are broken, and the impact on the biological environment of birds and the meteorological environment due to changes in air currents.

[0005] The problem to be solved by the present invention is to provide a new fluid power generation technology that does not require active rotation of a rotor. [Means for solving the problem]

[0006] A first invention for solving the above-mentioned problems is a fluid power generation system comprising a rotating body that can be rotated by a fluid, a rotating electric machine configured so that a rotor rotates in conjunction with the rotating body, and a control unit that performs vector control of the rotating electric machine so that a rotation index value indicating the rotational speed or rotational frequency of the rotating electric machine associated with the rotation of the rotating body is set to or approached to zero or a predetermined rotation target value corresponding to a predetermined frequency of 1 Hz or less for the rotational frequency of the rotating body.

[0007] The fluid power generation system of the first invention controls a rotation index value indicating the rotation speed or rotation frequency of a rotating electric machine configured such that a rotor rotates in conjunction with a rotating body, so that the rotation index value approaches zero or the rotation frequency approaches 1 Hz or less. As a result, the rotation speed of the rotating body during power generation can be suppressed to a state close to zero. This makes it possible to realize a new fluid power generation technology that does not require active rotation of the rotating body.

[0008] A second invention is directed to the fluid power generation system according to the above invention, wherein a rotating shaft of the rotating body and the rotor of the rotating electric machine are directly connected to each other.

[0009] A third invention is a fluid power generation system in accordance with the above-mentioned invention, further comprising a transmission mechanism for rotating the rotating shaft of the rotating body and the rotor of the rotating electric machine in conjunction with each other via a plurality of gears, the transmission mechanism being configured with a gear ratio such that the number of rotations of the rotating electric machine required for one rotation of the rotating body is 1 or less.

[0010] According to the second or third aspect of the present invention, the number of rotations of the rotating electrical machine is also suppressed, so that there are almost no mechanically rotating members in the power generating state, which makes it possible to eliminate problems such as noise.

[0011] A fourth invention is a control device that performs vector control of a rotating electric machine in a fluid power generation system including a rotating body that can be rotated by a fluid and a rotating electric machine whose rotor is configured to rotate in conjunction with the rotating body, and performs the vector control so that a rotation index value indicating the rotational speed or rotational frequency of the rotating electric machine associated with the rotation of the rotating body is set to or approached to zero or a predetermined rotation target value corresponding to a predetermined frequency of 1 Hz or less for the rotational frequency of the rotating body.

[0012] A fifth invention is a control method for vector controlling a rotating electric machine in a fluid power generation system including a rotating body that can be rotated by a fluid, and a rotating electric machine whose rotor is configured to rotate in conjunction with the rotating body, wherein the vector control is performed so that a rotation index value indicating the rotational speed or rotational frequency of the rotating electric machine associated with the rotation of the rotating body is set to or approached to zero or a predetermined rotation target value corresponding to a predetermined frequency of 1 Hz or less for the rotational frequency of the rotating body.

[0013] According to the fourth or fifth invention, like the other inventions described above, it is possible to realize a new fluid power generation technology that does not require high speed rotation of a rotor. [Brief description of the drawings]

[0014] [Figure 1] FIG. 2 is a diagram showing a configuration example of a main part of a fluid power generation system. [Diagram 2] FIG. 13 is a diagram showing an example of the configuration of a main part of another example of a fluid power generation system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] FIG. 1 is a diagram showing an example of the configuration of a main part of a fluid power generation system 10 to which the present invention is applied, and shows an example in which the system is applied to wind power generation. The fluid power generation system 10 includes a main body 1 including a rotor 12 and a rotating electric machine 14, a control unit 16, and a support unit 18 that supports the main body 1. Although the control unit 16 is illustrated as being separate from the main body 1 and the support unit 18, the control unit 16 may be disposed within the main body 1, or the control unit 16 may be disposed within the support unit 18.

[0016] The rotor 12 is configured to be rotatable by receiving air, which is a fluid in motion. A rotating shaft 12a of the rotor 12 and a rotor 14a of the rotating electric machine 14 are configured to rotate in conjunction with each other via a transmission mechanism 13.

[0017] The transmission mechanism 13 may be a mechanism that uses a connecting shaft that directly connects the rotating shaft 12a of the rotating body 12 and the rotor 14a of the rotating electric machine 14, or may have a configuration that has multiple gears and interlocks the rotating shaft 12a of the rotating body 12 and the rotor 14a of the rotating electric machine 14 via the gears. When multiple gears are interposed, the transmission mechanism 13 may be configured to have a first gear ratio that makes the number of rotations of the rotating electric machine 14 required for the rotating body 12 to rotate once (more precisely, the number of rotations of the rotor 14a) greater than 1, or may be configured to have a second gear ratio that makes the number of rotations of the rotating electric machine 14 required for the rotating body 12 to rotate once (more precisely, the number of rotations of the rotor 14a) equal to or less than 1. When the transmission mechanism 13 is configured to directly connect the rotating shaft 12a of the rotating body 12 and the rotor 14a of the rotating electric machine 14, the gear ratio is 1. As described below, by controlling the rotating electric machine 14 by vector control, it is possible to achieve a predetermined performance as the fluid power generation system 10 whether the gear ratio is set to 1 or the second gear ratio.

[0018] The rotating electric machine 14 is a generator configured such that the rotor 14a rotates in conjunction with the rotating body 12 via the transmission mechanism 13. The rotating electric machine 14 is, for example, an induction machine.

[0019] The control unit 16 has a vector control converter that realizes rotation control of the rotating electric machine 14 by vector control. The control unit 16 monitors a rotation index value indicating the rotation speed or rotation frequency of the rotating electric machine 14 accompanying the rotation of the rotor 12. The rotation index value corresponds to the rotation speed or rotation frequency of the rotating electric machine 14 that is determined when the control unit 16 calculates the rotation state (speed, magnetic flux, current) of the rotating electric machine 14 based on the current output voltage and output current of the rotating electric machine 14. The control unit 16 controls the rotation index value by vector control using the vector control converter so that the rotation frequency of the rotor 12 becomes zero or approaches a predetermined rotation target value that corresponds to a predetermined frequency of 1 Hz or less.

[0020] The rotation target value is input and set in advance in the control unit 16. The rotation target value may be stored in an IC memory mounted in the control unit 16, for example, or may be set by a plurality of dip switches or dial switches.

[0021] When the rotor 12 receives wind and tries to rotate, a torque is generated in the rotor 14a of the rotating electric machine 14, which rotates in conjunction with the rotor 12, causing the rotor 14a to try to rotate. The control unit 16 performs vector control to brake the rotation of the rotor 14a so as to suppress the change in rotation of the rotor 14a of the rotating electric machine 14. As a result, the rotating electric machine 14 of this embodiment functions as a regenerative generator while the rotor 12 appears to be not rotating or to be rotating at an extremely slow speed of 1 Hz or less.

[0022] As described above, the fluid power generation system 10 of the present embodiment can provide a new fluid power generation technology that does not require high speed rotation of a rotor.

[0023] [Modifications] Although an example of an embodiment to which the present invention is applied has been described, the forms to which the present invention can be applied are not limited to the above-described form, and constituent elements can be added, omitted, or modified as appropriate.

[0024] For example, in the above-described embodiment, an example was shown in which the fluid power generation system was applied to wind power generation, but it is also possible to apply it to hydroelectric power generation. In this case, the fluid used is liquid. For example, FIG. 2 shows an example of the configuration of the main parts of a fluid power generation system 10B applied to hydroelectric power generation. The configuration of the main parts of the fluid power generation system 10B is the same as that of the above-described fluid power generation system 10, and the main body 1B is configured to be supported below the water surface by a support part 18B supported by a support structure part 30.

[0025] In addition, in the above embodiment, the rotating electric machine 14 is exemplified as an induction machine, but a synchronous machine may also be used. [Explanation of symbols]

[0026] 10...Fluid power generation system 12...Rotating body 13...Transmission mechanism 14...Rotary electric machine 16...Control section

Claims

1. 1. A fluid power generation system, comprising: A rotor that can be rotated by a fluid; a rotating electric machine configured so that a rotor rotates in conjunction with the rotating body; a control unit that performs vector control of the rotating electric machine so that a rotation index value indicating a rotation speed or a rotation frequency of the rotating electric machine accompanying rotation of the rotating body is set to or approached to zero or a predetermined rotation target value corresponding to a predetermined frequency of 1 Hz or less of the rotation frequency of the rotating body; A fluid power generation system comprising:

2. The rotating shaft of the rotating body and the rotor of the rotating electric machine are directly connected. The fluid power generation system according to claim 1 .

3. a transmission mechanism for rotating a rotation shaft of the rotating body and the rotor of the rotating electric machine in cooperation with each other via a plurality of gears, the transmission mechanism being configured to have a gear ratio such that the number of rotations of the rotating electric machine required for one rotation of the rotating body is 1 or less; The fluid power generation system according to claim 1 , further comprising:

4. 1. A control device for vector-controlling a rotating electric machine in a fluid power generation system including a rotating body that can be rotated by a fluid and a rotating electric machine having a rotor that rotates in conjunction with the rotating body, comprising: performing the vector control so that a rotation index value indicating a rotation speed or a rotation frequency of the rotating electric machine accompanying the rotation of the rotating body is set to or approaches zero or a predetermined rotation target value corresponding to a predetermined frequency of 1 Hz or less of the rotation frequency of the rotating body; Control device.

5. 1. A control method for vector-controlling a rotating electric machine in a fluid power generation system including a rotating body that can be rotated by a fluid and a rotating electric machine having a rotor that rotates in conjunction with the rotating body, the control method comprising: A control method that performs vector control so that a rotation index value indicating the rotational speed or rotational frequency of the rotating electric machine accompanying the rotation of the rotating body is set to or approached to zero or a predetermined rotation target value corresponding to a predetermined frequency of 1 Hz or less for the rotational frequency of the rotating body.

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