JP6474701B2 - Generator controller, wind farm controller, and wind farm control method - Google Patents

Description

  The present invention relates to an energy farm (power generator group) in which at least two power generators equipped with power converters are installed, a power generator that suppresses harmonic currents flowing from the energy farm to the power system, the energy farm, and the energy The present invention relates to a farm control method.

  In recent years, the spread of renewable energy has progressed, and large-scale wind farms with a large number of wind power generation devices and large-scale solar farms with a large number of solar panels (solar power generation devices) have been constructed. Yes.

  Wind power generators and solar power generators include a power converter on the generator side that converts the generated power from AC to DC, and a power converter on the system side that converts the DC to AC and sends the power to the power system. I have. The power converter converts power from direct current to alternating current, or vice versa, by switching semiconductor elements. Distortion of current generated by switching when power is converted flows out into the power system as harmonic current.

  It is desirable to suppress this harmonic current to a reference value or less defined in the grid connection provision JEAC 9701-2012 (Non-Patent Document 1). Further, for example, in a wind farm, the switching of power converters of a plurality of wind power generators may be synchronized so that distortion of current flowing out from each wind power generator may be superimposed to amplify the harmonic current.

  As a technique for suppressing the harmonic current, for example, there is a technique as disclosed in Patent Document 1. Patent Document 1 discloses a “method for setting switching parameters (carrier wave phase, etc.) based on synchronized time information so that switching of power converters of a plurality of wind turbine generators is asynchronous”. Yes.

European Patent Application Publication No. 2482418A1

Grid interconnection regulations: JEAC 9701-2012, Japan Electric Association, February 2013, 6th edition

  By the way, in patent document 1, it is not assumed that the switching timing of the power converter of a wind power generator changes with wind conditions.

  Here, FIG. 2 shows an example in which the switching of the power converter of the wind power generator is made asynchronous by adjusting the phase of the carrier wave, which is one of the switching parameters, in two wind power generators having the same wind conditions. . FIG. 2 shows the carrier waves 10a and 10b, the target sine wave voltage 11, the power conversion of the first wind turbine generator (subscript a) and the second wind turbine generator (subscript b) having the same wind conditions. The voltage 12a and 12b which the device switches at the intersection of the carrier waves 10a and 10b and the target sine wave voltage 11 and outputs to the power system, and the currents 13a and 13b flowing in the power system by the voltages 12a and 12b are shown.

  In FIG. 2, like the method shown in Patent Document 1, carrier waves having different phases are set to the first and second wind power generators to make the switching of the power converter asynchronous. As a result, the time of the peak of the current distortion unevenness differs between the first and second wind power generators, and at the interconnection point where the sum of these currents flows, the current distortion is canceled and harmonics Wave current is suppressed.

  On the other hand, in two wind power generators with different wind conditions, an example in which the switching of the power converter of the wind power generator is synchronized in the method of Patent Document 1 is shown in FIG. In FIG. 3, the phase of the carrier wave is the same as in FIG. Since the wind conditions are different between the first and second wind power generators and the generated power of each wind power generator is different, there is a difference in the phase of the target sine wave voltage as in the target sine wave voltages 11a and 11b. . The relationship between the generated power and the target sine wave voltage is generally expressed by the relationship of equation (1).

  Where P is the generated power, Vs is the voltage of the power system, Vr is the target sine wave voltage, δ is the phase difference between the two voltages, and X is the reactance of the transmission line. FIG. 3 shows the case where the phase of the power system voltage Vs, the transmission line reactance X, the target sine wave voltage Vr, and the power system voltage is constant in the second wind turbine generator (subscript b). This is an example in which the phase of the target sine wave voltage has changed because the phase δ of both voltages has changed in accordance with the change of the power P.

  Since the phase of the target sine wave voltage has changed, the switching timing has changed, and the switching of the first and second wind turbine generators is synchronized at times T1 and T2. Therefore, in the method of Patent Document 1, if carrier waves having different phases are set in the power converters of a plurality of wind turbine generators without considering the difference in wind conditions, switching may be synchronized.

  On the other hand, in the two wind turbine generators having different wind conditions, the target sine wave voltages 11a and 11b are different between the first and second wind turbine generators as shown in FIG. Can be set to asynchronous switching of the power converter of the wind turbine generator.

  An object of the present invention is to suppress generation of harmonic currents by adjusting carrier wave information of power converters of a plurality of power generators under different conditions to make switching asynchronous.

The present invention is a controller for a power generation device including a power conversion device, a detection unit for detecting power generation information of the power generation device, a carrier wave phase settling unit for setting the phase of a carrier wave of the power conversion device, The carrier wave phase setter determines a phase of a carrier wave based on the power generation information detected by the detector, controls the power converter based on the phase of the determined carrier wave, and the power generator Is a wind power generator that generates power by receiving wind, or a solar power generator that generates power by receiving sunlight, and the power generation information is wind direction information in the wind power generator or the solar power generator. It is characterized by the amount of solar radiation information .

  The present invention is also a wind farm controller comprising a plurality of wind turbine generators equipped with a power converter, a wind direction detector for detecting wind direction information of the wind turbine generator, and a carrier wave of the power converter A carrier wave phase setter for setting the phase, and the carrier wave phase setter determines the phase of the carrier wave based on the wind direction information detected by the wind direction detector, and sets the phase of the carrier wave thus determined. The power converter is controlled based on the above.

  Further, the present invention is a wind farm control method comprising a plurality of wind power generators, and based on the wind direction information of each wind power generator constituting the wind farm, the carrier wave of the power converter of each wind power generator , And the power converter is controlled based on the determined phase of the carrier wave.

  According to the present invention, the generation of harmonic current is suppressed by adjusting carrier wave information of power converters of a plurality of power generators under different conditions such as a wind farm and a solar farm to make switching asynchronous. be able to. As a result, a reliable and stable power supply is possible in the energy farm (power generation device group).

  Problems, configurations, and effects other than those described above will become apparent from the following description of embodiments.

It is a block diagram which shows the structure of the wind power generator in 1st Example of this invention. It is a schematic diagram which shows an example in which switching of the power converter of two wind power generators with the same wind condition becomes asynchronous. It is a schematic diagram which shows an example in case switching of the power converter of two wind power generators from which a wind condition differs is synchronized. It is a schematic diagram which shows an example in which switching of a power converter becomes asynchronous with two wind power generators with different wind conditions. It is a figure which shows an example of the wind power generator group table stored in the setting database of the wind power generator in 1st Example of this invention. It is a figure which shows the arrangement | positioning of a wind power generator in a wind farm, and the relationship between a wind direction. It is a figure which shows an example of the carrier wave phase settling table stored in the settling database of the wind power generator in 1st Example of this invention. It is a flowchart explaining operation | movement of the wind power generator in 1st Example of this invention. It is a figure which shows an example of the current waveform by the wind power generator in 1st Example of this invention. It is a figure which shows an example of the current waveform by the wind power generator in 1st Example of this invention. It is a figure which shows an example of the current waveform by the wind power generator in 1st Example of this invention. It is a figure which shows an example of the current waveform by the wind power generator in 1st Example of this invention. It is a figure which shows an example of the current waveform by the wind power generator in 1st Example of this invention. It is a figure which shows an example of the current distortion rate by the wind power generator in 1st Example of this invention. It is a figure which shows an example of the current waveform by the method of patent document 1. FIG. It is a figure which shows an example of the current waveform by the method of patent document 1. FIG. It is a figure which shows an example of the current waveform by the method of patent document 1. FIG. It is a figure which shows an example of the current waveform by the method of patent document 1. FIG. It is a figure which shows an example of the current waveform by the method of patent document 1. FIG. It is a figure which shows an example of the current distortion rate by the method of patent document 1. FIG. It is a block diagram which shows the structure of the wind power generator in 2nd Example of this invention. It is a figure which shows an example of the table stored in the performance database in 2nd Example of this invention. It is a flowchart explaining operation | movement of the wind power generator group table preparation part in 2nd Example of this invention. It is a figure which shows the time change of the harmonic current of the connection point in 2nd Example of this invention. It is a block diagram which shows the structure of the wind power generator in 3rd Example of this invention. It is a figure which shows an example of the target sine wave voltage table stored in the performance database in 3rd Example of this invention. It is a figure which shows an example of the carrier wave table stored in the performance database in 3rd Example of this invention. It is a flowchart explaining operation | movement of the wind farm controller in 3rd Example of this invention. It is a figure which shows an example of the switching timing of the power converter by the wind farm controller in 3rd Example of this invention. It is a block diagram which shows the structure of the solar power generation device in 4th Example of this invention. It is a block diagram which shows the structure of the solar power generation device in 4th Example of this invention. It is a block diagram which shows the structure of the solar power generation device in 4th Example of this invention.

  Embodiments will be described below with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and detailed description of overlapping portions is omitted.

  First, with reference to FIG. 1, the structure of the wind farm 500 in a present Example is demonstrated. In this embodiment, a wind power generator is used as an example of the power generator.

  FIG. 1 is a diagram showing an embodiment of the present invention. FIG. 1 includes a wind power generator 100 (100a to 100d), a power transmission line 200 (200a to 200d), and a power system 300.

  A point where a plurality of wind power generators 100 (100a to 100d) are connected to the power system 300 via the power transmission lines 200 (200a to 200d) is defined as a connection point 400. A plurality of wind power generators 100 (100a to 100d) and power transmission lines 200 (200a to 200d) connecting them are collectively referred to as a wind farm 500.

  The wind power generator 100 (100a to 100d) includes a wind power generator 110, a power converter 120 that sends the power generated by the wind power generator 110 to the power system, and a settling device 130 that sets the phase of the carrier wave of the power converter. Consists of.

  Next, the configuration of the settling device 130 will be described. The settling device 130 includes a wind direction detector 131, a time synchronizer 132, a settling database 133, and a carrier wave phase setter 134.

  The wind direction detector 131 detects the wind direction of the wind flowing into the wind power generator 110. For detecting the wind direction, measurement information of an anemometer installed in the wind power generator 110 or a nacelle angle of the wind power generator is used.

  The time synchronization unit 132 synchronizes time information of a plurality of wind power generators in the wind farm 500. The time synchronization uses, for example, a method in which each wind power generator receives a signal from a GPS (Global Positioning System) satellite. Thereby, time information synchronized with an accuracy of about microseconds is obtained.

  The settling database 133 stores an identification number, a wind power generator group table, a carrier wave phase settling table, and a dead zone.

  The carrier wave phase setter 134 determines the set value of the carrier wave phase to be sent to the power converter 120 using various data sent from the wind direction detector 131, the time synchronizer 132, and the settling database 133. The carrier wave information to be determined by the carrier wave phase setter 134 includes, for example, a carrier wave phase and a carrier frequency.

  The identification number, wind power generator group table, carrier wave phase settling table, and dead zone stored in the setting database 133 will be described.

  The identification number is a number for distinguishing each wind power generator in the plurality of wind power generators 100 (100a to 100d) installed in the wind farm 500. For example, the four wind turbine generators 100 shown in FIG. 1 are given identification numbers such as 100a, 100b, 100c, and 100d.

  The wind turbine generator group table is a table in which a plurality of wind turbine generators 100 under similar wind conditions with respect to a predetermined wind direction are determined in advance. An example is shown in FIG. FIG. 5 is a group of numbers A1 to D2 in which the wind direction ranges separated by an arbitrary width and the wind power generators 100 under similar wind conditions for each wind direction range are grouped, It is the table which matched with the identification numbers 100a-100d of the wind power generator 100 which belongs to a group.

  For example, in the case of the arrangement of the wind power generators 100 (100a to 100d) shown in FIG. 6, the wind power generators arranged on the wind are 100a and 100b when the wind direction is in the range of 0 ° to 90 °. Is group A1. Moreover, the wind power generators arrange | positioned in the lee are 100c and 100d, and make them group A2. Furthermore, it is desirable to create a group table based on the arrangement interval of wind power generators, topographic undulations, obstacles, and the like. In addition, about the wind power generator in which two or more wind power generators exist in similar wind conditions, let them be other than that of the group number shown in FIG.

  The carrier wave phase settling table pre-sets the carrier wave phase settling value to each power converter so that the switching of the wind power generator power converter belonging to each group of the wind turbine group table becomes asynchronous. It is a table defined in. An example is shown in FIG. FIG. 7 is a table in which group numbers A1 to D2 corresponding to the wind power generator group table or other values are associated with the set value of the carrier wave phase of the power converter of each wind power generator.

  In each group of wind turbine generators having similar wind conditions (A1 to D2 shown in FIG. 7), switching is performed by giving a phase difference to the carrier wave phase of the power converter of each wind turbine generator as shown in FIG. Can be asynchronous. As for a plurality of wind turbine generators (other than those shown in FIG. 7) that do not have two or more wind turbine generators under similar wind conditions, as shown in FIG. 4, the power converter of each wind turbine generator Switching can be made asynchronous by setting the carrier wave phase of the same phase.

  The dead zone is a set value for preventing the wind power generator group from being changed in response to a minute change in the wind direction. For example, when the wind direction fluctuates by ± 5 ° centering on 90 °, the wind turbine generator 100b repeats the change of the groups A1 and B1 as shown in FIG. As the group is changed, the carrier wave phase is also changed, so that the output of the power converter may become unstable. Therefore, when the wind power generation apparatus 100b belongs to the group A1, when it exceeds 100 ° obtained by adding 10 ° of the dead zone to 90 °, the wind power generator 100b is changed to the group B1.

  Next, the operation of the carrier wave phase setter 134 in the settling device 130 will be described with reference to FIG.

  In step 11 (S11), the identification number, the wind power generator group table, the carrier wave phase setting table, and the dead zone are read from the setting database 133. Step 11 (S11) is executed each time the settling database 133 is updated.

  Subsequently, in step 12 (S12), a change in the wind direction is detected from the wind direction information of the wind direction detecting unit 131. If a change in the wind direction is detected, the process proceeds to step 13 (S13). If the wind direction has not changed, the process proceeds to step 12 (S12). Step 12 (S12) is executed in the wind direction detection cycle.

  Subsequently, in step 13 (S13), the identification number read in step 11 (S11), the wind power generator group table, the dead zone, and the wind direction information detected in step 12 (S12) are used. Determine the group to which the user belongs. When the range of the dead zone is added to the current direction of the group's wind direction, the group is changed. Further, the group may be changed when the integral value of the time exceeding the range exceeds a predetermined value.

  Subsequently, when the affiliation group is changed in step 14 (S14), the process proceeds to step 15 (S15). If not changed, the process proceeds to step 12 (S12).

  Subsequently, in step 15 (S15), using the carrier wave phase settling table read in step 11 (S11) and the group number determined in step 13 (S13), the carrier wave phase settling value is calculated. decide.

  Finally, in step 16 (S16), the phase of the carrier wave of the power converter is changed based on the time information synchronized with the plurality of wind turbine generators by the time synchronization unit 132.

  Thus, in the wind turbine generator 100 (100a to 100d) of the present embodiment, the carrier wave phase settling unit 134 of the settling device 130 converts the carrier wave phase changed according to the wind direction information of the wind direction detection unit 131 into power. Settling on vessel 120. Thereby, the harmonic currents flowing out from the plurality of wind turbine generators 100 (100a to 100d) cancel each other out, and the fluctuations are smoothed, so that the harmonic current flowing out from the wind farm 500 to the power system 300 can be suppressed. .

  Even when the wind farm 500 includes a plurality of wind power generators 100 (100a to 100d) having different wind conditions, the switching of the power converter 120 can be asynchronously performed. Also, by providing a dead band, it is possible to prevent the output of the power converter 120 from becoming unstable due to an excessive change in the carrier wave phase.

  In addition, when updating the set value of the phase of a carrier wave based on the wind direction information which each wind power generator 110 detected from the nacelle angle, with a centralized control server, its centralized control server, and the wind power generator 100 (100a-100d). A communication network for transmitting and receiving data is not required.

  Moreover, when providing the harmonic filter for suppressing a harmonic current in the power transmission line 200 (200a-200d) etc., the capacity | capacitance can be reduced.

  Here, an example of suppression of the harmonic current by the wind power generator in the present embodiment is shown in FIGS. 9A to 9E and FIG. 9A to 9E show current waveforms (FIGS. 9A to 9D) of the wind power generators 100 in the wind farm 500 configured by the wind power generators 100a to 100d as shown in FIG. FIG. 9E is a current waveform.

  The wind conditions of the wind power generators 100a and 100b and the wind power generators 100c and 100d are assumed to be equal. The grouping of the wind power generation apparatus 100 and the set value of the carrier wave phase are in the case where the wind direction range is 0 ° to 90 ° and the group numbers are A1 and A2 with reference to FIGS. 9A to 9E, the current waveform (FIG. 9E) at the interconnection point 400 approaches a sine wave with respect to the current waveform (FIGS. 9A to 9D) of each wind power generator 100 (100a to 100d). The harmonics are reduced. Moreover, as shown in FIG. 10, the current distortion rate of the current waveform (FIG. 9E) at the interconnection point 400 can be suppressed to about 1%.

  On the other hand, as in the method of Patent Document 1, examples of harmonic currents when the phase of the carrier wave is set without considering the difference in wind conditions of the wind power generator 100 (100a to 100d) are shown in FIGS. 11A to 11E. Shown in The phase of the carrier wave was set at 0 ° for the wind power generation device 100a, 90 ° for 100b, 180 ° for 100c, and 270 ° for 100d so that the phase difference would be equal between the four wind power generation devices.

  As shown in FIGS. 11A to 11E, in the method of Patent Document 1 as well, the current waveform of the interconnection point 400 (FIG. 11A to FIG. 11D) with respect to the current waveform (FIG. FIG. 11E) approaches a sine wave and the harmonics are reduced. However, as shown in FIG. 12, the current distortion rate of the current waveform at the interconnection point 400 (FIG. 11E) is about 2%. Therefore, it can be seen that the harmonic current can be further halved by the method of this embodiment.

  As described above, according to the present embodiment, harmonic current generation is achieved by adjusting carrier wave information of power converters of a plurality of wind turbine generators under different wind conditions to make switching asynchronous. Can be suppressed. As a result, a reliable and stable power supply can be achieved in the wind farm (wind power generation device group).

  In the present embodiment, in addition to the wind power generator 100 (100a to 100d) of the first embodiment, the wind farm that updates the wind power generator group database stored in the settling database 133 based on the actual data of the plurality of wind power generators. An example provided with a controller will be described.

  FIG. 13 is a block diagram illustrating the configuration of the wind turbine generator of the present embodiment. FIG. 13 shows a wind power generator 100 (100a to 100d), a power transmission line 200 (200a to 200d), a power system 300, a sensor 600 for detecting harmonics, a communication network 700, and a wind farm controller 800. FIG.

  Further, a point where the plurality of wind power generators 100 (100a to 100d) are connected to the power system 300 via the transmission lines 200 (200a to 200d) is a connection point 400, and the plurality of wind power generators 100 (100a to 100d). And a power transmission line 200 (200a to 200d) connecting them together to form a wind farm 500. The wind power generator 100 (100a to 100d) includes a settling device 130b instead of the settling device 130 of the first embodiment. Sensor 600 measures the harmonic current at interconnection point 400. The measured value of the harmonic current is sent to the wind farm controller 800 via the communication network 700.

  The settling device 130b of the present embodiment includes a power generation amount detection unit 135, a performance database 136, and a communication unit 137 in addition to the elements of the settling device 130. Of the elements of the settling device 130b, the elements denoted by the same reference numerals as those of the settling device 130 have the same functions and will not be described.

  The power generation amount detection unit 135 detects the power generation amount of the wind power generator 110 in the same time period as the wind direction detection unit 131, and sends the detected value to the performance database 136. The power generation amount is any index indicating the power generation amount of the wind power generator such as the apparent power, active power, current, rotation speed of the wind power generator 110, or the wind speed of an anemometer installed in the wind power generator 110.

  The result database 136 stores a wind direction / power generation result table. The wind direction / power generation amount actual table is a table in which detected values of the wind direction and the power generation amount are associated with the date and time when they are detected. An example is shown in FIG. FIG. 14 shows the detected values of the wind direction and the power generation amount detected every 10 minutes. For example, the detection value may be a value measured at each time every 10 minutes, or may be an average value for 10 minutes measured every second.

  The communication unit 137 is used to send the wind direction / power generation amount table of the result database 136 to the wind farm controller 800 via the communication network 700 and to receive the changed wind power generator group table from the wind farm controller 800. It is done.

  Next, the configuration of the wind farm controller 800 will be described. The wind farm controller 800 includes a communication unit 810, a performance database 820, and a wind power generator group table creation unit 830.

  The communication unit 810 transmits the wind power generation device group table to the wind power generation device 100 (100a to 100d) via the communication network 700, and the wind direction / power generation of the performance database 136 from the wind power generation device 100 (100a to 100d). Used to receive the quantity actual table.

  The result database 820 stores the wind direction / power generation amount result table of each result database 136 of the plurality of wind turbine generators 100 (100a to 100d) received via the communication unit 810.

  The wind turbine generator group table creation unit 830 is configured to store a plurality of wind turbine generators 100 (stored in the performance database 820 when the harmonic current measurement value of the sensor 600 received via the communication unit 810 exceeds an allowable value. The wind power generator group table is corrected using the wind direction / power generation result table 100a to 100d).

  Hereinafter, the operation of the wind turbine generator group table creation unit 830 in the wind farm controller 800 will be described with reference to FIG.

  In step 21 (S21), the measured value of the harmonic current is read from the sensor 600 that detects the harmonic. Note that step 21 (S21) is preferably executed in the measurement cycle of the sensor 600.

  Subsequently, in step 22 (S22), it is determined whether the measured value of the harmonic current exceeds a predetermined allowable value. If the allowable value is not exceeded, the process proceeds to step 23 (S23). If the allowable value is exceeded, the process proceeds to step 24 (S24).

  In step 23 (S23), 0 is substituted for the number of loops i, and the process proceeds to step 21 (S21).

  In step 24 (S24), it is determined whether the loop count i has reached a predetermined upper limit value. If the loop count i has reached the upper limit value, the process proceeds to step 25 (S25). If the upper limit has not been reached, the process proceeds to step 26 (S26).

  In step 25 (S25), the operator is warned that the harmonic current cannot be kept below the allowable value by correcting the wind power generator group table. The operator who receives this alarm plans harmonic countermeasures such as adding a harmonic filter.

  In step 26 (S26), it is determined whether the loop count i is 1 or more. When the loop count i is 1 or more, the routine proceeds to step 27 (S27). If the loop count i is 0, the process proceeds to step 28.

  In step 27 (S27), since the harmonic current could not be less than or equal to the allowable value in the wind turbine generator group table corrected in the previous loop, the range of the power generation amount serving as a reference for dividing the group in the wind turbine generator group table Reduce ΔW. For example, when the range ΔW of the average power generation amount is narrowed from 0.2 pu to 0.1 pu, 0.0 pu to 1.0 pu are divided into five groups, which is twice as many as ten groups. By subdividing the group in this way, wind power generators having a more similar target sine wave voltage 11 can be grouped as shown in FIG. As a result, when the carrier wave phase is set, the probability that switching is synchronized due to the difference between the target sine wave voltages 11a and 11b as shown in FIG. 3 is reduced.

  Subsequently, in step 28 (S28), the wind direction / power generation amount record tables of the plurality of wind power generation apparatuses 100 (100a to 100d) shown in FIG. 14 are read from the record database 820.

  Subsequently, in step 29 (S29), the average power generation amount of each wind power generator 100 (100a to 100d) is calculated for each wind direction range indicated in the wind power generator group table. The average power generation amount is obtained by calculating the average value of the power generation amount at each time in the wind direction / power generation result table shown in FIG.

  Subsequently, in step 30 (S30), the wind power generators are grouped using the average power generation amount in step 29 (S29) and the predetermined power generation amount range ΔW. For example, when the power generation range ΔW is 0.2 pu, 0.0 pu to 0.2 pu, 0.2 pu to 0.4 pu, 0.4 pu to 0.6 pu, 0.6 pu to 0.8 pu, 0.8 pu The wind power generation apparatus 100 (100a to 100d) whose average power generation amount belongs to each group is determined in five groups of ~ 1.0pu.

  Finally, in step 31 (S31), the wind power generator group table is corrected using the group information in step 30 (S30). In the wind turbine generator group table, as shown in FIG. 5, the group number for each wind direction and the identification number of the wind turbine generator 100 (100a to 100d) belonging to the group are described. In addition, in the grouping of step 30 (S30), when there is a group to which only one wind turbine generator 100 belongs, the group number shown in FIG. 5 is registered in the other group.

  In this way, the wind farm controller 800 of the present embodiment corrects the wind power generator group data table when the harmonic current measurement value of the sensor 600 exceeds the allowable value. The wind power generator group data table is created by using the wind direction / power generation amount result table of the result database 136 of the plurality of wind power generators 100 (100a to 100d). Further, when the harmonic current cannot be suppressed to an allowable value or less by correcting the wind power generator group data table, an alarm is issued to the operator of the wind farm 500. As a result, even if the amount of power generation of each wind power generator 100 (100a to 100d) with respect to the wind direction changes due to new construction of the building, weather conditions, etc., and the harmonic current increases, the wind power generator group data table is corrected and the harmonics are increased. Wave current can be suppressed. Further, when the harmonic current cannot be suppressed below the allowable value by adjusting the carrier wave phase of the carrier wave phase setter 134 of the wind turbine generator 100, an alarm is given to the operator, so that measures such as adding a harmonic filter can be taken. The operator can be informed of what is necessary.

  Here, an example of the suppression of the harmonic current at the interconnection point 400 by the wind farm controller 800 in this embodiment is shown in FIG. In FIG. 16, the harmonic current at the interconnection point 400 according to the method of this embodiment is indicated by a solid line 21, and the harmonic current when the method of this embodiment is not used is indicated by a broken line 22.

  In the method of this embodiment, the solid line 21 of the harmonic current exceeds the allowable value 23 of the harmonic current at time T1, and the wind power generator group table creation unit 830 of the wind farm controller 800 follows the flow shown in FIG. The power generator group table has been modified. At time T2, the first corrected wind power generator group table is transmitted from the wind farm controller 800 to each wind power generator 100 (100a to 100d). Thereby, the carrier wave phase of each wind power generator 100 (100a-100d) was changed, and the harmonic current of the grid connection point 400 was suppressed.

  However, since the harmonic current at the grid interconnection point 400 still exceeds the allowable value 23, the second correction of the wind turbine generator group table is performed. Similarly to the first time, the carrier wave phase of each wind power generator 100 (100a to 100d) was changed by the second corrected wind power generator group table, and the harmonic current was further suppressed. With the correction on the second day, the harmonic current (solid line 21) becomes equal to or less than the allowable value 23 at time T4, and the correction of the wind turbine generator group table ends.

  On the other hand, when the wind turbine generator group table is not updated by the method of the present embodiment, the harmonic current (dashed line 22) exceeds the allowable value 23 of the harmonic current at time T1. The current (broken line 22) continues to rise and exceeds the upper limit 24 defined by the grid connection at time T3.

Therefore, by correcting the wind power generator group table according to the method of the present embodiment, the carrier wave phase of each wind power generator 100 (100a to 100d) is appropriately set, and the harmonic current at the grid connection point is suppressed. As described above, according to the present embodiment, by adjusting the carrier wave information of the power converters of a plurality of wind turbine generators under different wind conditions and making the switching asynchronous, the harmonic current can be reduced. Generation | occurrence | production can be suppressed more effectively. As a result, more reliable and stable power supply can be achieved in the wind farm (wind power generation device group).

  Hereinafter, the configuration of the wind farm 500 in this embodiment will be described with reference to FIG. FIG. 17 is a diagram showing an embodiment of the present invention. FIG. 17 is a diagram illustrating the configuration of the wind power generator 100 (100a to 100d), the power transmission line 200 (200a to 200d), the power system 300, the communication network 700, and the wind farm controller 800b. Further, a point where the plurality of wind power generators 100 (100a to 100d) are connected to the power system 300 via the transmission lines 200 (200a to 200d) is a connection point 400, and the plurality of wind power generators 100 (100a to 100d). And a power transmission line 200 (200a to 200d) connecting them together to form a wind farm 500. The wind farm 500 includes a wind farm controller 800b instead of the wind farm controller 800 of the second embodiment.

  Next, the configuration of the wind power generator 100 will be described. The wind power generator 100 includes a wind power generator 110, a power converter 120, and a communication unit 150. The wind power generator 110 generates power based on wind energy. The power converter 120 sends the power generated by the wind power generator 110 to the power system. The communication unit 150 transmits the target sine wave voltage of the power converter 120 and the frequency and phase of the carrier wave to the wind farm controller 800b via the communication network 700. In addition, the phase of the changed carrier wave is received from the wind farm controller 800 b and sent to the power converter 120.

  Next, the configuration of the wind farm controller 800b will be described. The wind farm controller 800b includes a communication unit 810, a power converter database 840, a switching timing estimation unit 850, and a carrier wave phase settling unit 860.

  The communication unit 810 transmits the set value of the carrier wave phase created by the wind farm controller 800b to the plurality of wind turbine generators 100 (100a to 100d) via the communication network 700. Moreover, the target sine wave voltage and carrier wave of each power converter 120 are received from the plurality of wind turbine generators 100 (100a to 100d).

  The power converter database 840 stores a table of target sine wave voltages and carrier waves of each power converter 120 of the plurality of wind turbine generators 100 (100a to 100d). For example, as shown in FIG. 2, the target sine wave voltage is a solid line 11, and the carrier wave is a solid line 10a and a broken line 10b. An example of a table stored in the power converter database 840 is shown in FIGS. FIG. 18 is a table of target sine wave voltages, in which target sine wave voltages of a plurality of wind turbine generators 100 (100a to 100d) are associated with their detection times. The increment of the detection time is desirably set to a sufficiently small value with respect to the carrier frequency, for example, about several tens of microseconds. FIG. 19 is a table of carrier waves, in which identification numbers of a plurality of wind turbine generators 100 (100a to 100d) are associated with carrier wave amplitudes, frequencies, and phases. The carrier wave can be reproduced using amplitude, frequency, and phase information.

  The switching timing estimation unit 850 uses the target sine wave voltage and the amplitude, frequency, and phase of the carrier wave stored in the power converter database 840, and each power converter 120 of the plurality of wind turbine generators 100 (100a to 100d). The switching timing is estimated. Further, the estimated value of the switching timing and the phase of the carrier wave used for the estimation are sent to the carrier wave phase setter 860.

  The carrier wave phase settling unit 860 is configured such that the switching timing intervals of the plurality of wind turbine generators 100 (100a to 100d) are more than a predetermined value from the estimated switching timing value and the set value of the carrier wave phase by the switching timing estimation unit 850. Next, the carrier wave phase is corrected. Further, the corrected carrier wave phase is sent to the switching timing estimation unit 850. When it is confirmed that the switching timing interval is a predetermined value or more, the carrier wave phase at that time is sent to the communication unit 810.

  Hereinafter, the operations of the switching timing estimation unit 850 and the carrier wave phase setting unit 860 in the wind farm controller 800b will be described with reference to FIG.

  In step 31 (S31), the target sine wave voltage and carrier wave tables (FIGS. 18 and 19) of the plurality of wind turbine generators 100 (100a to 100d) are read from the power converter database 840. Note that step 31 (S31) is preferably executed every time power converter database 840 is updated.

  Subsequently, in step 32 (S32), the switching timing estimation unit 850 uses the target sine wave voltage and carrier wave table to switch the switching timings of the power converters 120 of the plurality of wind turbine generators 100 (100a to 100d). Is estimated. As shown in FIG. 2, since the power converter 120 switches at the intersection of the target sine wave voltage and the carrier wave, the switching timing of the power converter 120 can be estimated from the target sine wave voltage and the carrier wave.

  Subsequently, in step 33 (S33), a switching time interval ΔT is calculated from the estimated value of the switching timing in step 32 (S32). ΔT is an interval from the time when any one of the plurality of wind turbine generators 100 (100a to 100d) is switched to the time when any one is switched next. When a plurality of wind power generators 100 (100a to 100d) are switched at the same time, ΔT is 0.

  Subsequently, in step 34 (S34), it is determined whether the switching time interval ΔT is equal to or greater than a preset threshold value. If ΔT is greater than or equal to the threshold value, the process proceeds to step 38 (S38). When ΔT is smaller than the threshold value, the process proceeds to step 35 (S35).

  In step 35 (S35), the phase of the carrier wave of the power converter 120 of each wind power generator 100 (100a to 100d) is corrected so that the switching time interval ΔT is equal to or greater than the threshold value. For example, among the two wind turbine generators 100 that are switched when ΔT is small, the carrier wave phase of the wind turbine generator 100 that is switched later is delayed from 30 ° to 90 °. As a result, the switching timing of the wind turbine generator 100 that is switched later can be delayed, and ΔT increases.

  In step 36 (S36), 1 is added to the loop count i.

  In step 37 (S37), it is determined whether the loop count i is equal to or greater than a preset upper limit value. If the number of loops is greater than or equal to the upper limit value, the process proceeds to step 38 (S38). When the number of loops is smaller than the upper limit value, the process proceeds to step 32 (S32).

  Finally, in step 38, when the switching time interval ΔT is equal to or smaller than the threshold value, or the number of corrections of the carrier wave phase (the number of loops) is equal to or greater than the upper limit value, correction is made to the plurality of wind turbine generators 100 (100a to 100d). Transmit the set value of the carrier wave phase.

  In this way, the wind farm controller 800b according to the present embodiment uses the target sine wave voltage and the detected value of the carrier wave of each wind power generator 100 (100a to 100d) to generate a plurality of wind power generators 100 (100a to 100d). ) Of the carrier wave phase of the power converter 120 of each of the wind turbine generators 100 (100a to 100d) is created so that the switching in () is asynchronous. Further, the set value of the carrier wave phase is created so that the switching time interval of the plurality of wind turbine generators 100 (100a to 100d) is as large as possible. As a result, the harmonic current flowing out from each wind turbine generator cancels out the individual fluctuations, and the fluctuations are smoothed, so that the harmonic current flowing out from the wind farm 500 to the power system 300 can be suppressed. In addition, the leveling effect of the harmonic current can be maximized by increasing the switching time interval of the plurality of wind turbine generators 100 (100a to 100d).

  Here, FIG. 21 shows an example in which the switching of the plurality of wind turbine generators 100 (100a to 100d) is made asynchronous by the wind farm controller 800b in the present embodiment. FIG. 21 is a table showing switching timings of the plurality of wind turbine generators 100 (100a to 100d) estimated by the switching timing estimation unit 850. The switching timing before the carrier wave phase setting unit 860 corrects the set value of the carrier wave phase is indicated by black circles ●, and the switching timing after correction is indicated by white circles ○.

  In the method of this embodiment, according to the flow shown in FIG. 20, each wind power generator 100 (100a) is used as shown in FIG. 21, using the target sine wave voltage table shown in FIG. 18 and the carrier wave table shown in FIG. The switching timing of ˜100d) was estimated. When the switching is synchronized or the switching time interval ΔT is smaller than a preset threshold value, the carrier wave phase is corrected. In FIG. 21, before the carrier wave phase is corrected (indicated by black circles ●), the switching is synchronized between the wind power generations 100c and 100d. Thus, the switching time was advanced by advancing the carrier wave phase of the wind power generation 100d. Thereby, after correction of the carrier wave phase (indicated by white circles), switching of the wind power generations 100c and 100d could be made asynchronous. In addition, since the carrier wave phase is set so that each switching time interval ΔT of the wind power generator 100 (100a to 100d) is equal to or greater than a predetermined value, ΔT is equalized and the harmonic current smoothing effect is maximized. I was able to.

  As described above, according to the present embodiment, harmonic current generation is achieved by adjusting carrier wave information of power converters of a plurality of wind turbine generators under different wind conditions to make switching asynchronous. Can be reliably suppressed. As a result, more reliable and stable power supply can be achieved in the wind farm (wind power generation device group).

  The solar farm and solar farm controller in the present embodiment will be described with reference to FIGS. In the first to third embodiments, the wind power generator is used as an example of the power generator. However, in this embodiment, a solar power generator is described as an example. FIG. 22 is a block diagram showing a configuration of a photovoltaic power generation apparatus corresponding to FIG. 1 (Example 1). FIG. 23 is a block diagram showing a configuration of a photovoltaic power generation apparatus corresponding to FIG. 13 (Example 2). FIG. 24 is a block diagram showing a configuration of a photovoltaic power generation apparatus corresponding to FIG. 17 (Example 3).

  The difference between FIG. 1 and FIG. 22 is the difference in whether the power generation device installed in the energy farm (power generation device group) is the wind power generator 110 or the solar power generator 910. The wind direction detection unit 131 in FIG. 1 corresponds to the solar radiation amount detection unit 931 in FIG. Similarly, the difference between FIG. 13 and FIG. 23 and the difference between FIG. 17 and FIG. 24 are also differences between the wind power generator 110 and the solar power generator 910. The configurations in FIGS. 22 to 24 and their functions and effects are the same as those described in the first to third embodiments, and thus detailed description thereof will be omitted. However, the description will be given in the first to third embodiments. The effect of the wind power generator (wind farm) is the same as that of the solar power generator (solar farm) of the present embodiment.

  That is, by applying the method of Example 1 to Example 3 to a solar power generation device (solar farm), even when there are a plurality of solar power generation devices having different solar radiation amount conditions in the solar farm, Switching of the power converter of the photovoltaic power generator can be made asynchronous. As a result, the harmonic currents flowing out from the respective solar power generation devices are varied by canceling out the respective fluctuations, and the harmonic currents flowing out from the solar farm to the electric power system can be suppressed. Moreover, the capacity | capacitance of the harmonic filter required in order to suppress a harmonic current can be reduced.

  In addition, this invention is not limited to an above-described Example, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

  Each of the above-described configurations, functions, processing units, processing means, and the like may be realized by hardware by designing a part or all of them with, for example, an integrated circuit. Each of the above-described configurations, functions, and the like may be realized by software by interpreting and executing a program that realizes each function by the processor. Information such as programs, tables, and files for realizing each function may be stored in a memory, a hard disk, a recording device such as an SSD (Solid-State-Drive), or a recording medium such as an IC card, an SD card, or a DVD. it can.

  10, 10a, 10b ... carrier wave, 11, 11a, 11b ... target sine wave voltage, 12, 12a, 12b ... voltage, 13, 13a, 13b ... current, 100, 100a, 100b, 100c, 100d ... wind power generator, DESCRIPTION OF SYMBOLS 110 ... Wind power generator, 120 ... Power converter, 130, 130b ... Setting device, 131 ... Wind direction detection part, 132 ... Time synchronization part, 133 ... Setting database, 134 ... Carrier wave phase setting part, 135 ... Power generation amount detection part DESCRIPTION OF SYMBOLS 136 ... Performance database, 137 ... Communication part, 200, 200a, 200b, 200c, 200d ... Transmission line, 300 ... Electric power system, 400 ... Interconnection point, 500 ... Wind farm, 600 ... Sensor, 700 ... Communication network, 800 , 800b ... Wind farm controller, 810 ... Communication unit, 820 ... Results database, DESCRIPTION OF SYMBOLS 30 ... Wind power generator group table preparation part, 840 ... Power converter database, 850 ... Switching timing estimation part, 860 ... Carrier wave phase settling part, 900, 900a, 900b, 900c, 900d ... Solar power generation device, 910 ... Sun Photovoltaic generator, 931 ... Solar radiation amount detection unit, 1000 ... Solar farm, 1100, 1100b ... Solar farm controller, 1130 ... Solar power generation device group table creation unit.

Claims (13)

A controller of a power generation device including a power conversion device,
A detection unit for detecting power generation information of the power generation device;
A carrier wave phase setter for setting the phase of the carrier wave of the power converter,
The carrier wave phase setter determines the phase of the carrier wave based on the power generation information detected by the detector,
Controlling the power converter based on the phase of the determined carrier wave ;
The power generator is a wind power generator that generates power by receiving wind, or a solar power generator that generates power by receiving sunlight,
The said power generation information is the wind direction information in the said wind power generator, or the solar radiation amount information in the said solar power generator, The controller of the power generator characterized by the above-mentioned . It is a controller of the power generator according to claim 1, Comprising:
A time synchronization unit for synchronizing the time information of the power generator,
The carrier wave phase setting unit determines a phase of a carrier wave based on time information from the time synchronization unit, and controls switching timing of the power converter based on the determined phase of the carrier wave. A controller for a power generation device. It is a controller of the power generator according to claim 2,
A plurality of the power generation devices are installed,
The carrier wave phase settling unit performs grouping of the power generation devices based on power generation information detected by each detection unit of the power generation device and a predetermined group table,
A controller of a power generation device, wherein the power conversion device of each power generation device is controlled so that switching of the power conversion devices of the power generation devices belonging to the same group becomes asynchronous. It is a controller of the power generator according to claim 3,
When the power generation information exceeds a preset allowable range, or when the integral value of the time exceeding the preset allowable range exceeds a predetermined value, the carrier wave phase settling unit A power generator controller that changes the grouping of the power generators based on power generation information detected by each detector and a predetermined group table. It is a controller of the power generator according to claim 3,
The carrier wave phase settling unit controls the power conversion device of each power generator based on a carrier wave phase settling table in which a set value of a carrier wave phase at which switching of each power generator belonging to the same group becomes asynchronous is set in advance. A controller for a power generation device. It is a controller of the power generator according to claim 3,
A performance database for storing power generation information of the power generation device ;
The carrier wave phase setter performs grouping of the power generation devices based on the power generation information detected by each detection unit of the power generation device, a predetermined group table, and the power generation information of the performance database, and A controller for a power generation device, which controls a power conversion device of the device. A wind farm controller comprising a plurality of wind power generators equipped with a power converter,
A wind direction detector for detecting wind direction information of the wind turbine generator;
A carrier wave phase setter for setting the phase of the carrier wave of the power converter,
The carrier wave phase setter determines the phase of the carrier wave based on the wind direction information detected by the wind direction detector,
A wind farm controller that controls the power converter based on the determined phase of the carrier wave. A wind farm controller according to claim 7 ,
The carrier wave phase setter performs grouping of the wind power generators based on wind direction information detected by each wind direction detector of the wind power generator and a predetermined group table,
A wind farm controller that controls a power converter of each wind power generator so that switching of the power converter of each wind power generator belonging to the same group becomes asynchronous. A wind farm controller according to claim 7 ,
A power converter database that stores target sine wave voltage and carrier wave information of the power converter;
A switching timing estimation unit for estimating the switching timing of the power converter,
The switching timing estimation unit estimates the switching timing of the power converter based on the target sine wave voltage and carrier wave information of the power converter database,
The wind farm controller, wherein the carrier wave phase setter controls the power converter based on the estimated switching timing of the power converter. A wind farm controller according to claim 9 ,
The carrier wave phase setter controls the power converter so that the switching of the power converters of the plurality of wind power generators is asynchronous. A wind farm control method comprising a plurality of wind power generators,
Based on the wind direction information of each wind turbine generator that constitutes the wind farm, determine the phase of the carrier wave of the power converter of each wind turbine generator,
A wind farm control method, comprising: controlling the power converter based on the determined phase of the carrier wave. A wind farm control method according to claim 11 ,
The wind farm control method characterized by controlling the switching timing of the power converter based on wind direction information and time information of each wind power generator. A wind farm control method according to claim 11 ,
Based on the wind direction information detected by each wind direction detector of the wind power generator and a predetermined group table, grouping the wind power generator,
A wind farm control method comprising: controlling a power converter of each wind power generator so that switching of the power converter of each wind power generator belonging to the same group becomes asynchronous.

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