JP5795170B2 - Power generation system - Google Patents

Description

  The present invention relates to a power generation system, and more particularly to a power generation system in which two types of generators are combined so that power can be generated efficiently even when the driving force fluctuates, such as a wind turbine power generation system.

  In a conventional wind turbine power generation system or the like, it is known to use an induction generator or a permanent magnet type synchronous generator (see Patent Document 1 and Patent Document 2). As permanent magnet type synchronous generators, those of surface magnet type and embedded magnet type are widely known.

Japanese Patent Laid-Open No. 5-15198 JP 2002-34300 A

  A conventional permanent magnet type synchronous generator requires a power generator with a capacity corresponding to the output, and must be stopped when there is an input exceeding the capacity. Further, the permanent magnet type synchronous generator is expensive because many expensive permanent magnets are used for the field. Furthermore, since the magnetomotive force of the field (permanent magnet) is constant, the power factor cannot be controlled on the generator side.

  On the other hand, in an AC generator having an excitation winding, a power source is required for flowing current through the excitation winding.

  This invention is made | formed in view of this situation, Comprising: It aims at providing the electric power generation system which can generate | occur | produce efficiently efficiently also when the drive input to a generator fluctuates.

In order to achieve the above object, a power generation system according to the present invention includes a first rotating shaft having one end connected to driving means, a permanent magnet, and is fixed to the outer periphery of the first rotating shaft, A first rotor configured to be rotatable together with the first rotating shaft, and the first rotor is surrounded from the outside in the radial direction so as to maintain a predetermined radial gap on the outer periphery of the first rotor, and an AC flow path A first stator having a first armature winding, and a permanent magnet synchronous generator having one end coupled to the first rotating shaft and rotating together with the first rotating shaft A second rotating shaft configured to be capable of being fixed to the outer periphery of the second rotating shaft and rotatable together with the second rotating shaft, and a plurality of magnetic surfaces are formed radially outwardly spaced apart from each other. The second rotor, and the outer periphery of the second rotor so as to maintain a predetermined radial gap. Surrounds the second rotor from a radially outer, second stator having a second armature winding as a direct current flow path, the so current of each part of the second armature winding is DC first And a switched reluctance generator provided with a driver that switches energization to each part of the two armature windings .

  According to the present invention, even when the drive input to the generator fluctuates, the entire power generation system can efficiently generate power.

1 is a block diagram of a power generation system according to a first embodiment of the present invention. FIG. 2 is a partial block diagram illustrating a switched reluctance generator, a driver, and the like in FIG. FIG. 2 is a schematic cross-sectional view of a second rotor and a second stator in FIG. 1. It is an electric circuit diagram of the driver of the electric power generation system of a 2nd embodiment concerning the present invention. It is an electric circuit diagram of the driver of the electric power generation system of a 3rd embodiment concerning the present invention. It is a schematic cross-sectional view of the 2nd rotor and 2nd stator of the electric power generation system of 4th Embodiment which concerns on this invention.

  Hereinafter, an embodiment of a power generation system according to the present invention will be described with reference to the drawings.

[First Embodiment]
1st Embodiment which concerns on the electric power generation system of this invention is described using FIGS. 1-3. FIG. 1 is a block diagram of the power generation system of this embodiment. FIG. 2 is a partial block diagram showing the switched reluctance generator 20 and the driver 32 in FIG. 1, and shows an electric circuit diagram in the driver 32 and the like. FIG. 3 is a schematic cross-sectional view of the second rotor 23 and the second stator 22 of FIG.

  First, the configuration of the power generation system of this embodiment will be described.

  This power generation system includes a permanent magnet type synchronous generator 10 (in FIG. 1, “PMSG” which is abbreviated as “Permanent Magnet Synchronous Generator”) and a switched reluctance generator 20 (in FIG. 1, a switched reluctance generator). Abbreviated “SRG”). The permanent magnet type synchronous generator 10 may be either a surface magnet type or an embedded magnet type.

  The power generation system includes a converter 31, a driver 32, a DC connection unit 42, a capacitor 48, and an inverter 40.

  The drive input device 1 such as a windmill is mechanically connected to one end (left side in FIG. 1) of the rotating shaft (first rotating shaft 11) of the permanent magnet type synchronous generator 10. The rotating shaft (second rotating shaft 21) of the switched reluctance generator 20 is connected to the end of the first rotating shaft 11 on the opposite side (right side in FIG. 1) to the side where the drive input device 1 is present. ing. That is, the first and second rotating shafts 11 and 21 are directly connected on the same axis and are configured to rotate together.

  The permanent magnet type synchronous generator 10 includes a first rotor 13 and a first stator 12.

  A first armature winding 15 is wound around the first stator 12. The first rotor 13 is attached with a permanent magnet (not shown), and is supported rotatably together with the first rotating shaft 11.

  The converter 31 is electrically connected to the first armature winding 15 so that the first three-phase alternating current (first AC) output from the permanent magnet type synchronous generator 10 can be input and the input first 1AC can be converted into a first direct current (first DC). This converter 31 is electrically connected to the inverter 40 via a capacitor 48. Further, the converter 31 is electrically connected to the driver 32 via the direct current connection 42.

  The DC connection unit 42 electrically connects the converter 31 and the driver 32. The DC connection portion 42 includes a positive side wiring 42 a connected to the positive side of the first DC of the converter 31 and a negative side wiring 42 b connected to the negative side. Each wiring 42 a and 42 b is electrically connected to the driver 32.

  The inverter 40 can convert at least a part of the first DC output from the converter 31 into an output AC (second AC), that is, electric power of the power generation system and output the converted DC to the outside. The inverter 40 is electrically connected to the output unit 5 such as a system and can supply power to the output unit 5.

  The switched reluctance generator 20 includes a second rotor 23 and a second stator 22.

  The second rotor 23 is a cylindrical member fixed around the second rotation shaft 21, and has one nonmagnetic member 51 and four magnetic members 53 (FIG. 3).

  The nonmagnetic member 51 is formed of, for example, an aluminum alloy, surrounds a part of the outer peripheral surface of the second rotating shaft 21 from the outside in the radial direction, and is fixed to the outer peripheral surface. The nonmagnetic member 51 has four nonmagnetic portions 52 that protrude outward in the radial direction. These nonmagnetic parts 52 are formed at equal intervals in the circumferential direction. That is, the adjacent nonmagnetic portions 52 are formed so that the radial projecting directions are perpendicular to each other.

  Each magnetic member 53 is formed of, for example, a steel material or the like, and is attached between nonmagnetic portions 52 adjacent to each other in the circumferential direction.

  On the outer peripheral surface of the second rotor 23, there are a magnetic surface 53a at the radially outer end of each magnetic member 53 and a nonmagnetic surface 52a at the radially outer end of the nonmagnetic portion 52 applied to each nonmagnetic member 51. Four locations are formed alternately in the circumferential direction. That is, the four magnetic surfaces 53a and the four nonmagnetic surfaces 52a together form one cylindrical surface.

  The second stator 22 is an annular member disposed so as to surround the second rotor 23 from the outside in the radial direction, and six stator salient pole portions 55 are formed on the inner peripheral side. These stator salient pole portions 55 are arranged at equal intervals in the circumferential direction and are formed so as to protrude radially inward from the inner circumferential surface of the second stator 22. Ends on the radially inner side of the stator salient pole portions 55 are formed on the outer peripheral surface of the second rotor 23 so as to maintain a radial gap 54 therebetween.

  Although omitted in FIG. 3, the second armature winding 25 is disposed on the stator salient pole portions 55. The second armature winding 25 has three coils, that is, a first coil 25a, a second coil 25b, and a third coil 25c. These first to third coils 25a to 25c are electrically connected to the driver 32, respectively. Connection to the driver 32 will be described later.

  The driver 32 includes six transistor elements, that is, a first transistor element 61, a second transistor element 62, a third transistor element 63, a fourth transistor element 64, a fifth transistor element 65, and a sixth transistor element 66; And an electric circuit having a first diode element 71, a second diode element 72, a third diode element 73, a fourth diode element 74, a fifth diode element 75, and a sixth diode element 76. (FIG. 2).

  The first transistor element 61 and the first diode element 71 are electrically connected in series with each other. Similarly, each of the second to sixth transistor elements 62 to 66 and each of the second to sixth diode elements 72 to 76 are electrically connected in series with each other.

  Further, the first transistor element 61 and the first diode element 71 are connected from the positive electrode side (right side in FIG. 2) to which the positive electrode side wiring 42a is connected to the negative electrode side (left side in FIG. 2) to which the negative electrode side wiring 42b is connected. They are connected in this order. The third transistor element 63 and the third diode element 73, and the fifth transistor element 65 and the fifth diode element 75 are also connected in this order from the positive electrode side to the negative electrode side.

  On the other hand, the second transistor element 62 and the second diode element 72 are connected in this order from the negative electrode side to the positive electrode side. The fourth transistor element 64 and the fourth diode element 74, and the sixth transistor element 66 and the sixth diode element 76 are also connected in this order from the negative electrode side to the positive electrode side.

  Each end of the first coil 25a is electrically connected between the first transistor element 61 and the first diode element 71 and between the second transistor element 62 and the second diode element 72.

  The second coil 25 b is electrically connected between the third transistor element 63 and the third diode element 73 and between the fourth transistor element 64 and the fourth diode element 74. Similarly, the third coil 25 c is electrically connected between the fifth transistor element 65 and the fifth diode element 75 and between the sixth transistor element 66 and the sixth diode element 76.

  The first coil 25a is turned on by turning on and off the switches of the first and second transistor elements 61 and 62. The second coil 25b is turned on by turning on and off the switches of the third and fourth transistor elements 63 and 64. Similarly, the third coil 25c is turned on by switching on and off the fifth and sixth transistor elements 65 and 66.

  The driver 32 has a function of outputting the second DC flowing through the first to third coils 25 a to 25 c to the capacitor 48.

  The inverter 40 takes in at least a part of the second DC supplied from the driver 32 in addition to the first DC supplied from the converter 31 described above via the capacitor 48 and converts it into the second AC. It can be output as electric power.

  The determination unit 45a has a function of determining whether or not the rotational speed exceeds a predetermined value based on the result of measuring the rotational speed and the like of the first rotary shaft 11. This determination means 45a is supplied from the converter 31 when the rotational energy input to the permanent magnet type synchronous generator 10 exceeds a predetermined value, that is, when the rotational speed of the first rotating shaft 11 exceeds a predetermined value. A part of the supplied first DC is configured to be supplied to the driver 32. The first DC is supplied by the on / off operation of the first to sixth transistors 61 to 66 described above.

  The capacitor 48 has a function of temporarily accumulating the charge supplied from the driver 32 and then supplying it to the inverter 40.

  The inverter 40 converts the first DC and the second DC supplied from the converter 31 and the driver 32 to the second AC, that is, power, and supplies this power to the output unit 5 as described above.

  Next, power generation according to this embodiment will be described.

  First, power generation by the permanent magnet type synchronous generator 10 will be described.

  When there is a drive input to the power generation system by the drive input device 1, both the first and second rotary shafts 11 and 21 rotate. That is, the drive input device 1 inputs rotational energy to the power generation system.

  The permanent magnet type synchronous generator 10 generates electricity by the rotation of the first rotating shaft 11. In this case, the permanent magnet type synchronous generator 10 outputs the first AC from the first armature winding 15 of the first stator 12.

  A part (most part) of the output of the first AC generated from the first armature winding 15 is converted to the first DC by the converter 31, and then converted to the second AC by the inverter 40, to the output unit 5. Supplied. That is, the first AC is supplied to the output unit 5 through the converter 31, the inverter 40, and the like.

  When the drive input by the drive input device 1 is smaller than the predetermined power generation capacity of the permanent magnet type synchronous generator 10, that is, when the rotation speed of the first rotating shaft 11 is smaller than a predetermined value, The power generation system generates power only with the permanent magnet type synchronous generator 10. The switched reluctance generator 20 at this time acts as a flywheel.

  When the drive input by the drive input device 1 exceeds the power generation capacity of the permanent magnet type synchronous generator 10, the power generation system generates power using both the permanent magnet type synchronous generator 10 and the switched reluctance generator 20.

  In the following, a state where power is generated by the permanent magnet type synchronous generator 10 and the switched reluctance generator 20 will be described.

  When the determination unit 45a determines that the rotational energy input to the permanent magnet type synchronous generator 10 is greater than a predetermined value, that is, the determination unit 45a has the rotational speed of the first rotating shaft 11 greater than the predetermined value. When determined to be, the driver 32 is controlled so that at least one of the first to sixth transistor elements 61 to 66 is energized at a predetermined timing. Thus, by controlling the first to sixth transistor elements 61 to 66, the second DC flows through the first to third coils 25a to 25c. That is, the switched reluctance generator 20 is in a state where power generation is possible, that is, a state where the second DC is output from the second armature winding 25.

  When the second rotating shaft 21 rotates, each of the four magnetic surfaces 53a formed on the outer peripheral surface of the second rotor 23 moves along the circumferential direction. At this time, each of the magnetic surfaces 53a sequentially moves in a state where the radial gaps 54 are opposed to the radially inner end surfaces of the stator salient pole portions 55 of the second stator 22 while facing each other. When moving, at least two adjacent stator salient pole portions 55 are kept on one magnetic surface 53a so as to overlap each other in the radial direction. Thereby, magnetic flux is formed.

  The above-described magnetic flux changes due to a relative position change between the magnetic surface 53a and the adjacent stator salient pole portion 55. Due to the change in the magnetic flux, a force for stopping the rotation of the second rotor 23 acts. This force becomes an electromotive force, and the second DC different from the first DC (reverse direction) flows through the first to third coils 25a to 25c. This second DC is supplied to the inverter 40 via the capacitor 48. Thereafter, a part of the second DC is converted into the second AC by the inverter 40.

  At this time, the inverter 40 converts the first DC and the second DC into a second AC, and supplies the second AC to the output unit 5.

  As can be seen from the above description, according to the present embodiment, even when the drive input by the drive input device 1 fluctuates greatly, the permanent magnet type synchronous generator 10 using an expensive permanent magnet is always effectively used. Power generation can be continued and efficient use of the entire power generation system is possible.

[Second Embodiment]
The generator system of 2nd Embodiment is demonstrated using FIG. FIG. 4 is an electric circuit diagram of the driver 32 of the power generation system of the present embodiment. In addition, this embodiment is a modification of 1st Embodiment (FIGS. 1-3), Comprising: The same code | symbol is attached | subjected to the same part or similar part as 1st Embodiment, and duplication description is carried out. Omitted.

  Moreover, the whole structure of the electric power generation system of this embodiment is the same as that of FIG. 1 demonstrated in 1st Embodiment.

  The first power module 80 is used in the electric circuit of the driver 32 of the present embodiment. The first power module 80 is a general-purpose product in which a module transistor element 81 and a module diode element 82 are arranged in parallel to form a module.

  In this electric circuit (FIG. 4), each of the first to sixth transistor elements 61 to 66 shown in the electric circuit (FIG. 2) of the driver 32 described in the first embodiment is replaced with six first power modules 80. Replaced.

  Thereby, the effect similar to 1st Embodiment can be acquired. In addition, since a general-purpose product such as the first power module 80 can be used, the manufacture of the electric circuit is facilitated as compared with the first embodiment.

[Third Embodiment]
The generator system of 3rd Embodiment is demonstrated using FIG. FIG. 5 is an electric circuit diagram of the driver 32 of the power generation system of the present embodiment. In addition, this embodiment is a modification of 2nd Embodiment (FIG. 4), Comprising: The same code | symbol is attached | subjected to the same part or similar part as 2nd Embodiment, and duplication description is abbreviate | omitted.

  The second power module 90 is used in the electric circuit of the driver 32 of the present embodiment. The second power module 90 is a general-purpose product obtained by modularizing the first power module 80 shown in FIG. 4 described in the second embodiment and arranged in parallel.

  This electric circuit (FIG. 5) includes a first diode element 71 shown in the electric circuit (FIG. 4) of the driver 32 described in the second embodiment and a portion corresponding to one first power module 80. The second power module 90 is replaced.

  Similarly, the parts corresponding to the second to sixth diode elements 72 to 76 and the five first power modules 80 are replaced with the five second power modules 90.

  This makes it possible to obtain the same effect as in the second embodiment.

[Fourth Embodiment]
The generator system of 4th Embodiment is demonstrated using FIG. FIG. 6 is a schematic cross-sectional view of the second rotor 23 and the second stator 22 of the power generation system of the present embodiment. In addition, this embodiment is a modification of 1st Embodiment (FIGS. 1-3), Comprising: The same code | symbol is attached | subjected to the same part or similar part as 1st Embodiment, and duplication description is carried out. Omitted.

  The second rotor 23 of the present embodiment is fixed to the second rotating shaft 21 and rotates together with the second rotating shaft 21. The second rotor 23 has four rotor salient pole portions 59 projecting radially. Adjacent rotor salient pole portions 59 are formed so as to form 90 degrees with each other. Further, these rotor salient pole portions 59 correspond to the magnetic member 53 of FIG. 3, and the radially outer side forms a radial gap 54 on the radially inner side of the stator salient pole portion 55.

  Although the detailed illustration is omitted, the second rotor 23 is formed by laminating plate materials made of a steel material. Each plate material is formed with a rotor salient pole portion 59.

  The second rotor 23 is easier to manufacture than the first embodiment.

[Other Embodiments]
The description of the above embodiment is an example for explaining the present invention, and does not limit the invention described in the claims. Moreover, each part structure of this invention is not restricted to the said embodiment, A various deformation | transformation is possible within the technical scope as described in a claim.

  In the first to fourth embodiments, the number of the stator salient pole portions 55 of the switched reluctance generator 20 is six, and the number of the magnetic surfaces 53a or the rotor salient pole portions 59 on the rotor side is four. Although it is comprised by piece, it is not restricted to this. For example, the stator side may be 12 poles and the rotor side may be 8 poles. This can be modified according to various conditions such as the power generation capacity.

  Moreover, you may use the driver 32 of 2nd Embodiment (FIG. 4) or the driver 32 of 3rd Embodiment (FIG. 5) for the switched reluctance generator 20 of 4th Embodiment.

DESCRIPTION OF SYMBOLS 1 ... Drive input device, 5 ... Output part, 10 ... Permanent magnet type synchronous generator, 11 ... 1st rotating shaft, 12 ... 1st stator, 13 ... 1st rotor, 15 ... 1st armature winding, DESCRIPTION OF SYMBOLS 20 ... Switch reluctance generator, 21 ... 2nd rotating shaft, 22 ... 2nd stator, 23 ... 2nd rotor, 25 ... 2nd armature winding, 25a ... 1st coil, 25b ... 2nd coil, 25c ... 3rd coil, 31 ... Converter, 32 ... Driver, 40 ... Inverter, 42 ... DC connection, 42a ... Positive electrode side wiring, 42b ... Negative electrode side wiring, 45a ... Determination means, 48 ... Capacitor, 51 ... Nonmagnetic member 52 ... Nonmagnetic part, 52a ... Nonmagnetic surface, 53 ... Magnetic member, 53a ... Magnetic surface, 54 ... Radial gap, 55 ... Stator salient pole part, 59 ... Rotor salient pole part, 61 ... First transistor Element 62 ... second transistor element 63 ... third transistor Distor element, 64 ... fourth transistor element, 65 ... fifth transistor element, 66 ... sixth transistor element, 71 ... first diode element, 72 ... second diode element, 73 ... third diode element, 74 ... fourth diode Elements 75, fifth diode element, 76, sixth diode element, 80, first power module, 81, transistor element for module, 82, diode element for module, 90, second power module

Claims (3)

A first rotating shaft having one end connected to the driving means;
A first rotor comprising a permanent magnet, fixed to the outer periphery of the first rotating shaft, and configured to be rotatable together with the first rotating shaft;
A first stator including a first armature winding that surrounds the first rotor from the outside in the radial direction so as to maintain a predetermined radial gap on the outer periphery of the first rotor, and serves as an AC flow path ;
A permanent magnet type synchronous generator with
A second rotating shaft having one end connected to the first rotating shaft and configured to be rotatable together with the first rotating shaft;
A second rotor fixed to the outer periphery of the second rotating shaft and rotatable together with the second rotating shaft, wherein a plurality of magnetic surfaces are formed radially spaced apart from each other in the circumferential direction;
A second stator including a second armature winding that surrounds the second rotor from the outside in the radial direction so as to maintain a predetermined radial gap on an outer periphery of the second rotor, and serves as a DC flow path ;
A driver that switches energization to each part of the second armature winding so that a current of each part of the second armature winding becomes a direct current ;
A switched reluctance generator with
A power generation system comprising: And converter means for converting the pre-Symbol alternating current generated in the first armature winding into DC,
Inverter means for converting at least one of direct current obtained from the converter means and direct current obtained from the second armature winding into alternating current;
The power generation system according to claim 1, further comprising : Determination means for determining whether the measured value exceeds a predetermined value based on the result of measuring the rotation speed of the first rotation shaft;
The driver is
A portion of the direct current output from the converter means can be supplied to the second armature winding when the determination means determines that the predetermined value has been exceeded,
The power generation system according to claim 2.

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