JP5787872B2 - Wind power generation facility and operation method thereof - Google Patents

Description

  The present disclosure relates to a wind power generation facility that converts AC power generated by a wind power generator into DC power and transmits DC power to a grid side, and an operation method thereof.

  In recent years, large-scale wind power generation facilities have been popularized from the viewpoint of global environmental conservation. In general, a wind power generation facility supplies power output from a wind farm including a plurality of wind power generators to a grid (system).

Such a wind turbine generator will continue to operate if the system voltage drops due to the occurrence of an abnormal system event such as a power outage, as long as the degree of voltage drop or the duration of the voltage drop is within a predetermined range. In some cases, it is required to maintain grid connection. That is, the wind power generator linked to the grid is required to have an LVRT (Low Voltage Ride-Through) function.
When a system abnormal event occurs, control devices and various auxiliary devices (for example, pitch drive mechanisms) that are normally controlled by the power supplied from the grid side are disconnected from the grid side and maintained in operation. Can not. Therefore, in order to realize the LVRT function, a power supply source to a control device and various auxiliary devices necessary for continuing operation and maintaining interconnection to the grid is required.

  For example, Patent Document 1 discloses a configuration using an uninterruptible power supply (UPS) as one method for maintaining the operation of such devices during LVRT. This is because power is supplied from an uninterruptible power supply to necessary equipment (for example, a power converter, a turbine controller, a blade pitch control system, a crowbar circuit, etc.) when a drop in system voltage is detected. It has become.

US Patent No. 6921985

  However, the uninterruptible power supply described in Patent Document 1 requires a lot of maintenance, and since the battery used in the uninterruptible power supply is likely to deteriorate due to secular change, in order to maintain the function of the uninterruptible power supply. Need to replace the battery regularly. This increases the labor and cost required for maintenance of the wind power generation system.

  An object of at least one embodiment of the present invention is to provide a wind power generation facility capable of supplying power to equipment constituting the wind power generation apparatus in an emergency without using an uninterruptible power supply and an operation method thereof. .

  A wind power generation facility according to at least one embodiment of the present invention includes at least one wind power generation device, a DC power transmission path for supplying power to the grid from the at least one wind power generation device, and the at least one wind power generation device. Sending converter for converting the AC power from the DC power into the DC power transmission path and receiving converter for converting the DC power from the DC power transmission path into AC power and supplying it to the grid And a charge / discharge cable connected to the at least one wind power generator, the charge / discharge cable being charged by the power from the at least one wind power generator or the grid, and an abnormal event occurrence of the grid It is sometimes configured to discharge to the at least one wind power generator.

  In the wind power generation facility, the DC power transmission path is charged from the wind power generation apparatus when the grid (system) is normal, and the power charged in the DC power transmission path is supplied to at least one wind power generation apparatus in an emergency (for example, at LVRT). To discharge. Thereby, electric power can be supplied to the apparatus which comprises a wind power generator in an emergency, without using an uninterruptible power supply device, and operation | movement of a wind power generator can be maintained also in an emergency.

In some embodiments, the charge / discharge cable is a backup line of the DC power transmission path.
In this way, it is not necessary to separately lay a charge / discharge cable by using a backup line of a DC transmission line provided for providing redundancy to the DC transmission line as a charge / discharge cable. Therefore, the equipment cost can be reduced.

In some embodiments, it is provided between the charging / discharging cable as the backup line and the sending converter, and is opened when the DC transmission line is normal, and is closed when the DC transmission line is abnormal. Provided between the first circuit breaker configured as described above, the charge / discharge cable as the backup line and the receiving converter, and opened when the DC power transmission path is normal, and when the DC power transmission path is abnormal A second circuit breaker configured to be closed.
In the above embodiment, when the DC power transmission line is normal, the first circuit breaker and the second circuit breaker are opened, the charge / discharge cable is sent out, the converter and the receiving converter are disconnected, and the charge / discharge cable is charged from the wind turbine generator. It has become so. Further, when the DC transmission line is abnormal, the first circuit breaker and the second circuit breaker are closed, and the backup line can be replaced with the DC transmission line.
Thereby, only by operation of the 1st circuit breaker and the 2nd circuit breaker, the reserve line of a direct-current power transmission line can be used as a charge / discharge cable, or it can be made to substitute for a direct-current power transmission line.

  A method for operating a wind power generation facility according to at least one embodiment of the present invention includes at least one wind power generation device, a direct current transmission line for supplying power from the at least one wind power generation device to a grid, and the at least one wind power generation device. A sending converter for converting AC power from a wind power generator into DC power and supplying it to the DC power transmission path, and for converting the DC power from the DC power transmission path into AC power and supplying it to the grid And a charging / discharging cable connected to the at least one wind power generator, wherein the charge / discharge is performed by power from the at least one wind power generator or the grid. A charging step of charging a cable, and power supply to the at least one wind turbine generator when an abnormal event of the grid occurs. There characterized in that it comprises a discharge step of discharging from the charging and discharging cable as supplied.

  According to the operation method of the wind power generation facility, the DC power transmission path is charged from the wind power generator when the grid is normal, and at least one wind power is supplied to the DC power transmission path in an emergency (for example, LVRT). Discharge to the generator. Thereby, electric power can be supplied to the apparatus which comprises a wind power generator in an emergency, without using an uninterruptible power supply device, and operation | movement of a wind power generator can be maintained also in an emergency.

  According to at least one embodiment of the present invention, without using an uninterruptible power supply, power can be supplied to equipment constituting the wind power generator in an emergency, and the operation of the wind power generator can be maintained even in an emergency. .

It is a figure which shows the whole structure of the wind power generation facility which concerns on one Embodiment of this invention. It is a figure which shows the whole structure of the wind power generation facility which concerns on other embodiment of this invention. It is a flowchart which shows the operating method of the wind power generation facility which concerns on other embodiment of this invention. It is a figure which shows the whole structure of the wind power generation facility which concerns on the modification of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described below as the embodiments or shown in the drawings as the embodiments are not intended to limit the scope of the present invention. It is just an example.

FIG. 1 is a diagram illustrating an overall configuration of a wind power generation facility according to an embodiment.
As shown in the figure, in some embodiments, the wind power generation facility 1 includes at least one wind power generation device 10 and transmits the power output from the wind power generation device 10 to the grid 50 via the local grid 2. It is like that.

  The wind power generator 10 includes, as main devices, a windmill rotor and a generator that converts rotational energy of the windmill rotor into electric energy. As the generator of the wind power generator 10, for example, a synchronous generator or an induction generator is used. Furthermore, the wind power generator 10 includes various auxiliary machines such as a pitch driving mechanism that adjusts the pitch angle of the blades, and a control device that controls these devices. The power output from the wind power generator 10 is output to the local grid 2 as AC power. In addition, although the one wind power generator 10 is shown in FIG. 1, you may be comprised with the wind farm containing a some wind power generator.

  The local grid 2 includes an AC power transmission path 11, a DC power transmission path 12, and an AC power transmission path 13 as a main power transmission path provided between the wind power generation apparatus 10 and the grid 50 in order from the wind power generation apparatus 10 side. A charge / discharge cable 20 connected to the power generation apparatus 10 is included.

The main power transmission line is provided with a sending converter (SEC) 3 constituted by an AC / DC converter, a receiving converter (REC) 4 constituted by an orthogonal converter, and a transformer 5. ing.
The sending converter 3 converts the AC power from the wind power generator 10 into DC power and supplies it to the DC power transmission path 12. The receiving converter 4 converts the DC power from the DC power transmission path 12 into AC power and supplies it to the grid 50. The transformer 5 transforms the AC power converted by the receiving converter 4.

  In one embodiment, the DC power transmission path 12 is provided with a first circuit breaker 7 and a second circuit breaker 8. The first circuit breaker 7 and the second circuit breaker 8 mainly disconnect the sending converter 3 and the receiving converter 4 from the DC power transmission path 12 when a short-circuit accident or a ground fault occurs in the DC power transmission path 12. It plays a role to protect against overvoltage or overcurrent. When there is no abnormality in the grid 50 and the local grid 2, the first circuit breaker 7 and the second circuit breaker 8 are all closed, and the power generated by the wind turbine generator 10 is directed to the grid 50 through the DC power transmission path 12. Power is transmitted.

In one embodiment, the charge / discharge cable 20 is connected to the wind turbine generator 10 via the AC / DC converter 26. The charge / discharge cable 20 is configured to be charged by electric power from the wind power generator 10 or the grid 50 and to discharge the wind power generator 10 when an abnormal event of the grid 50 occurs. That is, the generated power of the wind power generator 10 is converted into DC power by the AC / DC converter 26, and the charge / discharge cable 20 is charged by the DC power. When an abnormal event occurs in the grid 50, the DC power from the charge / discharge cable 20 is converted into AC power by the AC / DC converter 26, and the AC power is supplied to the wind power generator 10.
A plurality of the charge / discharge cables 20 may be provided. A transformer 21 and a switch 22 are provided between the charge / discharge cable 20 and the wind power generator 10. The switch 22 is controlled to be opened and closed by a charge / discharge control unit 40 described later.

  In the wind power generation facility 1, at least one wind power generation device 10 and the sending converter 3 may be installed on the ocean, and the receiving converter 4, the transformer 5, and the grid 50 may be installed on land. In this case, most of the DC power transmission path 12 and the charge / discharge cable 20 are submarine cables installed on the seabed.

  In some embodiments, the wind power generation facility 1 controls charging / discharging of the charge / discharge cable 20 by controlling a switch 22 and an AC / DC converter 26 provided between the charge / discharge cable 20 and the wind power generator 10. The charging / discharging control part 40 which switches between discharge is further provided.

Before the occurrence of an abnormal event in the grid 50, the charge / discharge control unit 40 controls the switch 22 and the AC / DC converter 26, and with the switch 22 closed, the power from the wind power generator 10 or the grid 50 is converted into the AC / DC converter. The direct current power is converted into direct current power by 26 and the direct current power is supplied to the charge / discharge cable 20. Thereby, the charging / discharging cable 20 is charged. When the charging / discharging cable 20 is charged, the switch 22 is opened and the control of the AC / DC converter 26 is stopped.
On the other hand, when an abnormal event occurs in the grid 50, the switch 22 and the AC / DC converter 26 are controlled, and the DC power from the charge / discharge cable 20 is converted into AC power by the AC / DC converter 26 with the switch 22 closed. Then, the AC power is supplied to the wind power generator 10.
Here, the detection unit 42 may detect the terminal voltage of the generator of the wind power generator 10 and determine whether or not an abnormal event has occurred in the grid 50 based on the terminal voltage of the generator.

  In this way, by charging the charging / discharging cable 20 from the wind turbine generator 10 when the grid 50 is normal and supplying an electric power from the charging / discharging cable 20 to the wind turbine generator 10 when an abnormal event occurs in the grid 50. Without using an uninterruptible power supply, electric power can be supplied to the equipment constituting the wind turbine generator 10 at LVRT, and the operation of the wind turbine generator 10 can be maintained even at LVRT.

FIG. 2 is a diagram showing an overall configuration of a wind power generation facility according to another embodiment of the present invention.
As shown in FIG. 2, a backup line 12 ′ provided in parallel with the DC power transmission path 12 as the main line may be used as the charge / discharge cable 20. Thus, by using the spare line 12 ′ provided for providing redundancy to the DC power transmission path (main line) 12 as the charge / discharge cable 20, there is no need to separately lay the charge / discharge cable 20. Therefore, the equipment cost can be reduced.

  In the exemplary embodiment shown in FIG. 2, between the DC transmission line (main line) 12 and the sending converter 3, and between the DC transmission line 12 and the receiving converter 4, the sending converter, respectively. A third circuit breaker (SEC side circuit breaker) 7a and a receiving converter 4 side second circuit breaker (REC side circuit breaker) 8a are provided. Similarly, a first circuit breaker 7b and a second circuit breaker 8b are provided between the protection line 12 'and the sending converter 3, and between the protection line 12' and the receiving converter 4, respectively.

The first circuit breakers 7a and 7b and the second circuit breakers 8a and 8b are controlled to be opened and closed by the DC circuit breaker control unit 60, and when the DC power transmission path (main line) 12 is abnormal, the DC power transmission path 12 is sent out and the converter 3 and It may be separated from the receiving converter 4 and replaced by the protection line 12 ′.
That is, when the DC transmission line (main line) 12 is normal, the DC breaker control unit 60 closes both the first circuit breaker 7a and the second breaker 8a of the DC transmission line (main line) 12, and Both the first circuit breaker 7b and the second circuit breaker 8b of the protection line 12 ′ are in an open state. On the other hand, when the DC transmission line (main line) 12 is abnormal, the DC circuit breaker control unit 60 opens the first circuit breaker 7a and the second circuit breaker 8a of the DC transmission line (main line) 12. The first circuit breaker 7b and the second circuit breaker 8b of the line 12 ′ are closed. In this way, the DC power transmission line (main line) 12 in which an abnormality has occurred is replaced by the protection line 12 ′.

  Further, the standby line 12 ′ also serves as the charge / discharge cable 20, and is therefore connected to the wind power generator 10 via the AC / DC converter 36. In one embodiment, as shown in FIG. 2, the connection line 30 constituted by the AC line 31 and the DC line 32 located on both sides of the AC / DC converter 36 is connected to the first line 12 ′ as the charge / discharge cable 20. It is connected to a connection point 33 in the vicinity of the circuit breaker 7b. The AC line 31 may be provided with a transformer 35.

The charge / discharge control unit 40 controls the switch 37 and the AC / DC converter 36 before the occurrence of an abnormal event in the grid 50, and AC / DC converts the electric power from the wind power generator 10 or the grid 50 with the switch 37 closed. The converter 36 converts the DC power into DC power and supplies the DC power to the charge / discharge cable 20 (backup line 12 ′). Thereby, the charging / discharging cable 20 is charged. When the charge / discharge cable 20 is charged, the switch 37 is opened and the control of the AC / DC converter 36 is stopped.
On the other hand, when an abnormal event of the grid 50 occurs, the switch 37 and the AC / DC converter 36 are controlled, and the DC power from the charge / discharge cable 20 is converted into AC power by the AC / DC converter 36 with the switch 37 closed. Then, the AC power is supplied to the wind power generator 10.
In addition, at the time of charging / discharging of the charging / discharging cable 20 (protection line 12 '), the 1st circuit breaker 7b and 2nd circuit breaker 8b of the both sides of the charging / discharging cable 20 (protection line 12') are carried out by the DC circuit breaker control part 60. Open

Here, with reference to FIG. 3, the operating method of the wind power generation facility 1 which concerns on one Embodiment is demonstrated.
During normal operation of the wind power generation facility 1 (S1), the AC / DC converters 26 and 36 are controlled with the switches 22 and 37 closed, and the charge / discharge cables 20 and 12 ′ are powered by the power from the wind power generator 10 or the grid 50. (20) is charged (S2). When the charge / discharge cables 20, 12 ′ (20) are charged, the switches 22, 37 are opened, and the control of the AC / DC converters 26, 36 is stopped.
Then, the terminal voltage of the wind power generator 10 is detected by the detection part 42, and the presence or absence of generation | occurrence | production of the abnormal event in the grid 50 is determined based on a terminal voltage (S3). If it is determined that an abnormal event has occurred in the grid 50, the switches 22 and 37 are closed, and the AC / DC converters 26 and 36 are controlled to supply power to the wind turbine generator 10 from the charge / discharge cables 20, 12 ′ (20) ( Discharge) (S4).
Thereby, even if it is a case where electric power supply cannot be received from the grid 50, operation | movement of the wind power generator 10 can be maintained.

  As described above, according to the above-described embodiment, the charging / discharging cables 20, 12 ′ (20) are charged when the grid 50 is normal, and the charging / discharging cables 20, 12 are performed when an abnormal event of the grid 50 occurs. 'The electric power charged in (20) is discharged to at least one wind power generator 10. Thereby, electric power can be supplied to the apparatus which comprises the wind power generator 10 at the time of LVRT, without using an uninterruptible power supply device.

  As mentioned above, although embodiment of this invention was described in detail, it cannot be overemphasized that this invention is not limited to this, In the range which does not deviate from the summary of this invention, various improvement and deformation | transformation may be performed.

For example, in the above-described embodiment, the occurrence of an abnormal event in the grid 50 is determined based on the terminal voltage of the wind turbine generator 10, but the abnormal event in the grid 50 is determined based on voltage information on the grid 50 side or on the grid 50 side. You may determine based on the accident information including the open / close state of the circuit breaker in each place of the grid 50 which can be acquired from the substation or the power supply command station.
FIG. 4 is a diagram showing an overall configuration of the wind power generation facility 1 according to a modification of the present invention. As shown in FIG. 4, the occurrence of an abnormal event may be detected based on a signal from a system monitoring unit 52 provided in the grid 50. In addition, the system monitoring unit 52 monitors the state of various facilities constituting the grid 50, information on sensors installed at various places, and reports the monitoring results to the charge / discharge control unit 40 of the wind power generation facility 1. It has become. In this case, the charge / discharge control unit 40 may determine whether or not an abnormal event has occurred in the grid 50 based on the report result from the system monitoring unit 52.

DESCRIPTION OF SYMBOLS 1 Wind power generation facility 2 Local grid 3 Sending converter 4 Receiving converter 5, 21, 35 Transformer 7, 7a, 7b 1st circuit breaker 8, 8a, 8b 2nd circuit breaker 10 Wind power generator 11, 13 AC power transmission path 12 DC transmission line 12 'Backup line (charge / discharge cable)
20 Charge / Discharge Cable 22, 37 Switch 30 Connection Line 40 Charge / Discharge Control Unit 42 Detection Unit 50 Grid 52 System Monitoring Unit

Claims (5)

At least one wind power generator installed on the ocean ;
A DC transmission line for supplying power to the grid from the at least one wind turbine generator;
A sending-out converter for converting alternating current power from the at least one wind power generator into direct current power and supplying the direct current power to the direct current transmission line;
A receiving converter for converting the DC power from the DC power transmission path into AC power and supplying it to the grid;
A charge / discharge cable connected to the at least one wind turbine generator;
The charge / discharge cable includes a submarine cable installed on the seabed,
The charge / discharge cable is configured to be charged by electric power from the at least one wind power generator or the grid, and to discharge to the at least one wind power generator when an abnormal event occurs in the grid. Wind power generation facility. At least one wind power generator;
A DC transmission line for supplying power to the grid from the at least one wind turbine generator;
A sending-out converter for converting alternating current power from the at least one wind power generator into direct current power and supplying the direct current power to the direct current transmission line;
A receiving converter for converting the DC power from the DC power transmission path into AC power and supplying it to the grid;
A charge / discharge cable connected to the at least one wind turbine generator;
The charging / discharging cable is configured to be charged by electric power from the at least one wind power generator or the grid, and to be discharged to the at least one wind power generator when an abnormal event occurs in the grid,
Before KiTakashi discharge cables, wind power generation facilities you being a standby line of the DC power transmission path. A first cutoff provided between the charging / discharging cable as the backup line and the sending converter, and configured to be opened when the DC transmission line is normal and closed when the DC transmission line is abnormal And
A second cutoff provided between the charge / discharge cable as the backup line and the receiving converter, and configured to be opened when the DC transmission line is normal and closed when the DC transmission line is abnormal The wind power generation facility according to claim 2, further comprising: At least one wind power generator installed on the ocean, a DC power transmission path for supplying power to the grid from the at least one wind power generator, and AC power from the at least one wind power generator is converted to DC power A sending converter for supplying to the DC power transmission path, a receiving converter for converting the DC power from the DC power transmission path into AC power and supplying it to the grid, and the at least one wind power generation A method for operating a wind power generation facility including a submarine cable, wherein the charge / discharge cable is installed on a seabed .
A charging step of charging the charge / discharge cable with power from the at least one wind turbine generator or the grid;
And a discharging step of discharging from the charging / discharging cable so that electric power is supplied to the at least one wind power generator when an abnormal event of the grid occurs. At least one wind power generator, a DC power transmission path for supplying power to the grid from the at least one wind power generator, and AC power from the at least one wind power generator is converted to DC power to convert the DC power Connected to the at least one wind power generator, a sending converter for supplying to the electrical path, a receiving converter for converting the DC power from the DC power transmission path to AC power and supplying it to the grid, and A charge / discharge cable, wherein the charge / discharge cable is a backup line of the DC power transmission path, and is a method for operating a wind power generation facility,
A charging step of charging the charge / discharge cable with power from the at least one wind turbine generator or the grid;
And a discharging step of discharging from the charging / discharging cable so that electric power is supplied to the at least one wind power generator when an abnormal event of the grid occurs.

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