A power generation system, a wind storage converter and a power closed-loop control method thereof

Abstract

The application provides a power generation system, a wind storage variable flow device and a power closed loop control method thereof. A second current voltage detection module is additionally arranged on the first side of a direct current conversion module in the wind storage variable flow device. In the power closed loop control method, the output power of the machine side conversion module in the wind storage variable flow device changes with the change of the power generation power of the wind turbine and is not affected by the transmission power of the direct current conversion module, so that the power generation power of the wind turbine is closed loop controlled according to the output power of the machine side conversion module, and the power generation power of the wind turbine tends to be stable, and therefore the power closed loop control method of the wind storage variable flow device provided by the application can realize smooth power generation of the wind turbine.

Description

Technical Field

[0001] This invention relates to the field of automatic control technology, and in particular to a power generation system, a wind-storage converter, and a power closed-loop control method thereof. Background Technology

[0002] like Figure 1 As shown, the wind power converter connects the wind turbine to the grid and performs closed-loop control on the grid-connected power of the wind power converter based on the given values ​​of the grid-connected power of the wind power converter and the output power of the wind turbine. This ensures that the adjustment of the grid-connected power of the wind power converter is consistent with the adjustment of the given value of the output power of the wind turbine. The grid-connected power is based on... Figure 1 The results were obtained from the detection of the first current sensor CT1 and the first voltage sensor PT1.

[0003] In addition, it is also possible to use, such as Figure 2 The wind-storage converter shown connects the wind turbine to the grid. In contrast, a DC-DC converter module is added to the wind-storage converter. The first side of the DC-DC converter is connected to the DC bus in the wind-storage converter, allowing the converter to be connected to an energy storage system. However, if the power closed-loop regulation is still applied, the adjustment of the grid-connected power of the wind-storage converter cannot be consistent with the adjustment of the setpoint value of the wind turbine's output power. For example, when the setpoint value of the wind turbine's output power increases, the grid-connected power of the wind-storage converter is reduced.

[0004] Therefore, how to keep the adjustment of the grid-connected power of the wind-storage converter consistent with the adjustment of the setpoint of the output power of the wind turbine is an urgent technical problem to be solved. Summary of the Invention

[0005] In view of this, the present invention provides a power generation system, a wind-storage converter, and a power closed-loop control method thereof, so that the adjustment of the grid-connected power of the wind-storage converter is consistent with the adjustment of the given value of the output power of the wind turbine.

[0006] To achieve the above objectives, the embodiments of the present invention provide the following technical solutions:

[0007] This application provides a power closed-loop control method for a wind-storage converter, the wind-storage converter comprising: a DC-DC converter module and / or an AC-DC converter module, wherein a first side of the DC-DC converter module is connected to the DC bus in the wind-storage converter, and an AC side of the AC-DC converter module is connected to the generator side or the grid side of the wind-storage converter; the power closed-loop control method includes:

[0008] The DC transmission power of the DC-DC converter and / or the AC transmission power of the AC-AC converter are determined based on the current and voltage of the DC-DC converter and / or the current and voltage of the AC-AC converter.

[0009] Using the grid-connected power of the wind-storage converter, as well as the DC transmission power and / or the AC transmission power, the actual value of the output power of the wind turbine connected to the wind-storage converter is determined.

[0010] The grid-connected power is adjusted in a closed loop based on the actual value of the output power and the given value of the output power.

[0011] Optionally, if the transmission direction of the DC-DC converter or the AC-DC converter is: flowing into the wind-storage converter, then when determining the actual value of the output power, the DC transmission power or the AC transmission power is subtracted from the grid-connected power.

[0012] Optionally, if the transmission direction of the DC-DC converter or the AC-DC converter is outflow from the wind-storage converter, then when determining the actual value of the output power, the DC transmission power or the AC transmission power is added to the grid-connected power.

[0013] Optionally, based on the actual value of the output power and the given value of the output power, closed-loop regulation of the grid-connected power is performed, including:

[0014] Determine whether the actual value of the output power is greater than the given value of the output power;

[0015] If the actual value of the output power is greater than the given value of the output power, then the grid-connected power is reduced;

[0016] If the actual value of the output power is less than the given value of the output power, then the grid-connected power is increased.

[0017] Optionally, before determining whether the actual value of the output power is greater than the given value of the output power, the method further includes:

[0018] Determine whether the absolute value of the difference between the actual value of the output power and the given value of the output power is greater than the hysteresis threshold;

[0019] If the absolute value is greater than the hysteresis threshold, then the step of determining whether the actual value of the output power is greater than the given value of the output power is executed.

[0020] A second aspect of this application provides a wind-storage converter, comprising: a machine-side conversion module, a grid-side conversion module, a first controller, a first current and voltage detection module, and a DC-DC conversion module and / or an AC-DC conversion module; wherein:

[0021] The AC side of the generator-side conversion module is connected to the generator in the wind turbine, and the AC side of the grid-side conversion module is connected to the power grid.

[0022] The DC side of the machine-side conversion module is connected to the DC side of the grid-side conversion module via a DC bus.

[0023] The first side of the DC-DC converter module is connected to the DC bus;

[0024] The AC side of the AC converter module is connected to either the AC side of the machine-side converter module or the AC side of the network-side converter module.

[0025] The detection terminal of the first current and voltage detection module is located on the AC side of the grid-side conversion module, and the output terminal of the first current and voltage detection module is connected to the first controller.

[0026] The turbine-side converter module, the grid-side converter module, the DC-DC converter module, the main controller of the wind turbine generator, and the DC-DC converter module and / or the AC-DC converter module are all controlled by the first controller, which is used to execute the power closed-loop control method of the wind-storage converter as described in any of the first aspects of this application.

[0027] Optionally, the second side of the DC-DC converter module is connected to: the connection port of the energy storage system and / or the connection port of the photovoltaic system;

[0028] The DC side of the AC converter module is connected to: the connection port of the energy storage system and / or the connection port of the photovoltaic system.

[0029] Optionally, it may also include: a second controller and a second current and voltage detection module and / or a third current and voltage detection module; wherein:

[0030] The detection terminal of the second current and voltage detection module is located on the first side of the DC-DC converter module, and the detection terminal of the third current and voltage detection module is located on the AC side of the AC-DC converter module.

[0031] The output terminals of the second current and voltage detection module and the third current and voltage detection module are both connected to the second controller, and the second controller is communicatively connected to the first controller.

[0032] Optionally, the second controller and the first controller are integrated into a single controller.

[0033] Optionally, the current and voltage detection module includes a voltage sensor and a current sensor.

[0034] Optionally, if the generator is a doubly-fed generator, the wind-storage converter further includes: a stator-side switch; wherein:

[0035] One end of the stator-side switch is connected to the stator of the generator, and the other end of the stator-side switch is connected to the AC side of the grid-side conversion module.

[0036] A third aspect of this application provides a power generation system, comprising: a wind turbine generator, a transformer, and a wind-storage converter; wherein:

[0037] The wind-storage converter is connected to the wind turbine generator on the turbine side, the wind-storage converter is connected to the primary side of the transformer on the grid side, and the transformer is connected to the power grid on the secondary side.

[0038] The wind-storage converter is the wind-storage converter as described in any of the second aspects of this application, or the main controller in the wind turbine is used to execute the power closed-loop control method of the wind-storage converter as described in any of the first aspects of this application.

[0039] Optionally, it may also include: energy storage systems, or energy storage systems and photovoltaic systems.

[0040] Optionally, when the main controller is used to execute the power closed-loop control method of the wind-storage converter:

[0041] The connection port of the energy storage system is connected to: the second side of the DC-DC converter module in the wind-storage converter, or the DC side of the AC-DC converter module in the wind-storage converter;

[0042] The connection port of the photovoltaic system is connected to: the second side of the DC conversion module in the wind-storage converter, or the DC side of the AC conversion module in the wind-storage converter.

[0043] As can be seen from the above technical solution, the present invention provides a power closed-loop control method for a wind-storage converter. In this wind-storage converter, a DC-DC converter module and / or an AC-DC converter module are added. The first side of the DC-DC converter module is connected to the DC bus in the wind-storage converter, and the AC side of the AC-DC converter module is connected to the turbine side or grid side of the wind-storage converter. In this power closed-loop control method, firstly, the DC transmission power of the DC-DC converter module and / or the AC transmission power of the AC-DC converter module are determined based on the current and voltage of the DC-DC converter module and / or the current and voltage of the AC-DC converter module. Then, using the grid-connected power of the wind-storage converter, as well as the DC transmission power and / or AC transmission power, the actual value of the output power of the wind turbine connected to the turbine side of the wind-storage converter is determined. Finally, based on the actual value of the output power of the wind turbine and the given value, the grid-connected power of the wind-storage converter is adjusted in a closed loop. Since the given and actual output power of the wind turbine are not affected by the DC or AC transmission power, the power closed-loop control method of the wind-storage converter provided in this application can ensure that the adjustment of the grid-connected power of the wind-storage converter is consistent with the adjustment of the given output power of the wind turbine. Attached Figure Description

[0044] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0045] Figure 1 This is a schematic diagram of the structure of a wind power generation system in the prior art;

[0046] Figure 2 This is a schematic diagram of the structure of a wind-storage power generation system in the existing technology;

[0047] Figures 3-5 These are schematic flowcharts illustrating three implementation methods of the power closed-loop control method for the wind-storage converter provided in this application.

[0048] Figures 6-9 These are schematic diagrams illustrating three implementations of the wind-storage converter provided in this application.

[0049] Figures 10-12 These are schematic diagrams illustrating the structures of three implementations of the power generation system provided in this application. Detailed Implementation

[0050] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0051] In this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0052] In existing technologies, such as Figure 1 As shown, the wind power generation system includes: wind turbine generators ( Figure 1 (Not shown in the diagram, only the generator M represents the wind turbine unit), wind power converter 01 and transformer 05; wherein, the wind power converter 01 specifically includes: rotor-side switch 02, first current sensor 03, first voltage sensor 04, machine-side conversion module 06 and grid-side conversion module 07; wherein, machine-side conversion module 06 is an inverter module and grid-side conversion module 07 is a rectifier module.

[0053] The connection relationships between the various components in this wind power generation system are as follows:

[0054] The output terminal of the wind turbine is connected to the AC side of the turbine-side conversion module 06; the DC side of the turbine-side conversion module 06 is connected to the DC side of the grid-side conversion module 07 via a DC bus; the AC side of the grid-side conversion module 07 is connected to the primary side of the transformer 05 via the rotor-side switch 02, and the secondary side of the transformer 05 is connected to the power grid; the detection terminals of the first current sensor 03 and the first voltage sensor 04 are both located between the rotor-side switch 02 and the primary side of the transformer 05.

[0055] During operation, the power control method implemented by wind power converter 01 is as follows:

[0056] The wind power converter 01 first determines the set value of the wind turbine's output power issued by the main control unit based on the given torque and the current speed of the wind turbine. Then, based on the detection results of the first current sensor 03 and the first voltage sensor 04, it determines the grid-connected power of the wind power converter 01. Finally, based on the grid-connected power of the wind power converter 01 and the set value of the wind turbine's output power, it performs closed-loop control on the grid-connected power of the wind power converter 01, thereby ensuring that the adjustment of the grid-connected power of the wind power converter 01 is consistent with the adjustment of the set value of the wind turbine's output power.

[0057] When a wind power generation system is converted into a wind-storage power generation system, it is only necessary to replace the wind power converter 01 with the wind-storage converter 08. Specifically, as follows: Figure 2 As shown, the wind-storage converter 08 adds a DC-DC converter module 09 to the wind power converter 01, wherein the first side of the DC-DC converter module 09 is connected to the DC bus.

[0058] In a wind-storage power generation system, changes in the transmission power of the DC-DC converter module 09 will cause changes in the grid-connected power of the wind-storage converter 08. Therefore, if the power closed-loop adjustment is still performed as described above, the adjustment of the grid-connected power of the wind-storage converter 08 cannot be consistent with the adjustment of the given value of the output power of the wind turbine.

[0059] To ensure that the regulation of the grid-connected power of the wind-storage converter is consistent with the regulation of the setpoint output power of the wind turbine, this application provides a power closed-loop control method for the wind-storage converter. The wind-storage converter includes a DC-DC converter module 30 and / or an AC-DC converter module 40, as detailed in [reference needed]. Figure 6 ( Figure 6 (This demonstration only uses the addition of DC-DC converter module 30 as an example) Figure 7 (The example shown is an AC converter module 40 added to the AC side of the generator-side converter module 10. The first side of the DC converter module 30 is connected to the DC bus in the wind-storage converter, and the AC side of the AC converter module 40 is connected to the generator side or grid side of the wind-storage converter.)

[0060] The detailed flowchart of the power closed-loop control method is shown below. Figure 3 As shown, the specific steps include:

[0061] S110. Determine the DC transmission power of the DC converter module and / or the AC transmission power of the AC converter module based on the current and voltage of the DC converter module and / or the current and voltage of the AC converter module.

[0062] In practical applications, the current and voltage of the DC-DC converter module and / or the AC-DC converter module can be obtained by setting up sensors. Alternatively, the current and voltage of the DC-DC converter module can be obtained directly from the DC-DC converter module, and / or directly from the AC-DC converter module.

[0063] It should be noted that the method for determining DC transmission power and / or AC transmission power is the same as that in the prior art, and will not be repeated here.

[0064] S120. Using the grid-connected power of the wind-storage converter, as well as the DC transmission power and / or AC transmission power, determine the actual value of the output power of the wind turbine connected to the wind-storage converter.

[0065] The grid-connected power and its determination method have been explained in the above introduction to the specific structure and working principle of the wind-storage converter, and will not be repeated here.

[0066] In practical applications, the specific process for determining the actual output power of the wind turbine connected to the wind-storage converter is as follows:

[0067] If the transmission direction of the DC-DC converter or AC-DC converter is: flowing into the wind-storage converter, then when determining the actual value of the output power of the wind turbine, the DC transmission power or AC transmission power is subtracted from the grid-connected power of the wind-storage converter.

[0068] If the transmission direction of the DC-DC converter or AC-DC converter is outflow from the wind-storage converter, then when determining the actual output power of the wind turbine, the DC transmission power or AC transmission power is added to the grid-connected power of the wind-storage converter.

[0069] For example, only a DC-DC converter module is added to the wind-storage converter, and the transmission direction of the DC-DC converter module is: when it flows into the wind-storage converter, the actual value of the output power of the wind turbine is equal to the grid-connected power of the wind-storage converter minus the DC transmission power.

[0070] S130. Based on the actual output power of the wind turbine and the given output power of the wind turbine, the grid-connected power of the wind-storage converter is adjusted in a closed loop.

[0071] In this embodiment, since the given value and actual value of the wind turbine's output power are not affected by the DC transmission power or AC transmission power, the power closed-loop control method of the wind-storage converter provided in this embodiment can ensure that the adjustment of the grid-connected power of the wind-storage converter is consistent with the adjustment of the given value of the wind turbine's output power.

[0072] Furthermore, in existing technologies, if the wind-storage converter is still regulated according to the power closed loop in the wind power converter, the regulation of the grid-connected power of the wind-storage converter by the energy storage system based on the load power will be offset by the power closed loop. That is, the grid-connected power of the wind-storage converter is still equal to the given value of the output power of the wind turbine. As a result, the grid-connected power of the wind-storage converter cannot match the load power, and the energy storage system cannot achieve frequency regulation of the output current of the wind-storage converter.

[0073] It is worth noting that in the power closed-loop control method of the wind-storage converter provided in the embodiments of this application, since the basis for adjusting the grid-connected power of the wind-storage converter is the actual value of the output power of the wind turbine and the given output power of the wind turbine, the energy storage system can adjust the output current of the wind-storage converter according to the load power, which may not match the load power. Thus, the energy storage system can achieve frequency regulation of the output current of the wind-storage converter.

[0074] Another embodiment of this application provides a specific implementation of step S130, the specific process of which is as follows: Figure 4 As shown, the specific steps include:

[0075] S210. Determine whether the actual value of the wind turbine's output power is greater than the given value of the wind turbine's output power.

[0076] If the actual output power of the wind turbine is greater than the given output power of the wind turbine, then proceed to step S220; if the actual output power of the wind turbine is less than the given output power of the wind turbine, then proceed to step S230.

[0077] The given value of the wind turbine's output power is determined based on the given torque and the current speed of the wind turbine.

[0078] It should be noted that in practical applications, the given torque of the wind turbine is issued by the main controller of the wind turbine, and the current speed of the wind turbine is obtained by measuring the corresponding sensor. Both are the same in existing technology and will not be elaborated here.

[0079] S220, reduce the grid-connected power of the wind-storage converter.

[0080] S230, Increase the grid-connected power of the wind-storage converter.

[0081] This embodiment provides a specific implementation method for regulating the grid-connected power of the wind-storage converter, specifically: by increasing the machine-side current of the wind-storage converter, the rotor active current of the generator in the wind turbine is increased; by decreasing the machine-side current of the wind-storage converter, the rotor active current of the generator in the wind turbine is decreased.

[0082] The above is only one specific implementation method for regulating the grid-connected power of the wind-storage converter. In practical applications, there are other methods, including but not limited to this one. No specific limitation is made here, and all are within the protection scope of this application, depending on the specific circumstances.

[0083] This embodiment also provides another specific implementation of step S130, the specific process of which is as follows: Figure 5 As shown, before step S210, the following steps are also included:

[0084] S310. Determine whether the absolute value of the difference between the actual value of the wind turbine's output power and the given value of the wind turbine's output power is greater than the hysteresis threshold.

[0085] If the absolute value of the difference between the actual output power of the wind turbine and the given output power of the wind turbine is greater than the hysteresis threshold, then proceed to step S210; if the absolute value of the difference between the actual output power of the wind turbine and the given output power of the wind turbine is less than or equal to the hysteresis threshold, then return to proceed to step S110.

[0086] The hysteresis threshold is a power difference value preset according to the actual situation. Setting the hysteresis threshold can reduce erroneous control caused by errors, that is, reduce the frequency of adjustment of the output power of the wind turbine, so that the wind turbine can stabilize more quickly.

[0087] The above are merely two implementations of step S130, and are not specifically limited here. Both are within the protection scope of this application and can be determined according to specific circumstances.

[0088] Another embodiment of this application provides a wind-storage converter, the specific structure of which can be found in [reference needed]. Figure 6 ( Figure 6 (This demonstration only uses the addition of DC-DC converter module 30 as an example) Figure 7 (This example only demonstrates the addition of an AC conversion module 40 to the AC side of the machine-side conversion module 10), specifically including: machine-side conversion module 10, grid-side conversion module 20, and a first controller ( Figure 6 or Figure 7 (The image is a simplified view and is not shown), a first current and voltage detection module 50, and a DC-DC conversion module 30 and / or an AC-DC conversion module 40.

[0089] In this wind-storage converter, the AC side of the generator-side conversion module 10 is connected to the generator M in the wind turbine. In practical applications, the AC side of the generator-side conversion module 10 is connected to the rotor of the generator M.

[0090] The AC side of the grid-side conversion module 20 is connected to the power grid; in practical applications, such as... Figure 6 or Figure 7As shown, a rotor-side switch 60 can be added between the AC side of the grid-side conversion module 20 and the power grid. No specific limitation is made here, and it can be determined according to the specific situation. All of these are within the protection scope of this application.

[0091] Preferably, the rotor-side switch 60 is a circuit breaker; however, in practical applications, it may include, but is not limited to, this is not specifically limited here, and may be determined according to the specific circumstances, all of which are within the protection scope of this application.

[0092] The DC side of the machine-side conversion module 10 is connected to the DC side of the grid-side conversion module 20 via a DC bus.

[0093] The first side of the DC-DC converter module 30 is connected to the DC bus, such as... Figure 6 As shown; the second side of the DC-DC converter module 30 is connected to the connection port of the energy storage system and / or the connection port of the photovoltaic system. No specific limitation is made here, and it can be determined according to the specific situation. All of them are within the protection scope of this application.

[0094] The AC side of the AC conversion module 40 is connected to the AC side of the machine-side conversion module 10 (e.g., Figure 7 (as shown), or, the AC side of the grid-side conversion module, which is not specifically limited here and can be determined according to the specific situation, and is within the protection scope of this application; the DC side of the AC conversion module 40 is connected to: the connection port of the energy storage system and / or the connection port of the photovoltaic system, which is not specifically limited here and can be determined according to the specific situation, and is within the protection scope of this application.

[0095] The output terminal of the first current and voltage detection module 50 is connected to the first controller; the detection terminal of the first current and voltage detection module 50 is located on the AC side of the grid-side conversion module 20; when a rotor-side switch 60 is added between the AC side of the grid-side conversion module 20 and the power grid, the detection terminal of the first current and voltage detection module 50 is located between the power grid and the rotor-side switch 60.

[0096] The turbine-side conversion module 10, the grid-side conversion module 20, the main controller of the wind turbine, and the DC conversion module 30 and / or AC conversion module 40 are all controlled by a first controller, which is used to execute the power closed-loop control method of the wind-storage converter as provided in the above embodiments.

[0097] Preferably, the first current and voltage detection module 50 includes a voltage sensor and a current sensor; in practical applications, it includes, but is not limited to, the specific implementation details, and may be determined according to the specific circumstances, all of which are within the scope of protection of this application.

[0098] The wind-storage converter provided in the above embodiments is only applicable to the case where the generator M in the wind turbine is a full-power generator, but not to the case where the generator M in the wind turbine is a dual-feedback generator. In order to be applicable to the latter, another embodiment of this application provides another implementation of the wind-storage converter, the specific structure of which is as follows: Figure 8 (only in) Figure 6 As shown in the figure, it also includes: stator side switch 70.

[0099] In this embodiment, one end of the stator-side switch 70 is connected to the stator 101 of the generator M of the wind turbine, and the other end of the stator-side switch 70 is connected to the AC side of the grid-side conversion module 20.

[0100] Preferably, the stator-side switch 70 is a circuit breaker; however, in practical applications, it may include, but is not limited to, this application. It may be determined according to the specific circumstances and is within the scope of protection of this application.

[0101] Another embodiment of this application provides another implementation of the wind-storage converter, the specific structure of which can be found in [reference needed]. Figure 9 ( Figure 9 Only Figure 6 Based on the above, it also includes: a second controller and a second current and voltage detection module 80 and / or a third current and voltage detection module.

[0102] The detection terminal of the second current and voltage detection module 80 is located on the first side of the DC-DC converter module 30, and the detection terminal of the third current and voltage detection module is located on the AC side of the AC-DC converter module 40. The output terminals of the second current and voltage detection module 80 and the third current and voltage detection module are both connected to the second controller, and the second controller is communicatively connected to the first controller.

[0103] Preferably, both the second current and voltage detection module 80 and the third current and voltage detection module include voltage sensors and current sensors; in practical applications, this may include, but is not limited to, and is not specifically limited here, depending on the specific circumstances, and is within the protection scope of this application.

[0104] It should be noted that in another embodiment of the wind-storage converter, the second controller can also be combined with the first controller to form a single controller. No specific limitation is made here, and it can be determined according to the specific circumstances. All of these are within the protection scope of this application.

[0105] Another embodiment of this application provides a power generation system, the specific structure of which is as follows: Figure 10 As shown, it specifically includes: wind turbine 400, transformer 100 and wind-storage converter 200.

[0106] In this power generation system, the wind-storage converter 200 is connected to the wind turbine 400 on the turbine side, the wind-storage converter 200 is connected to the primary side of the transformer 100 on the grid side, and the transformer 100 is connected to the power grid 300 on the secondary side.

[0107] It should be noted that the specific way the wind-storage converter 200 is connected to the wind turbine 400 on the machine side has been described in detail in the above embodiments, and will not be repeated here.

[0108] Optionally, the wind-storage converter 200 can be the wind-storage converter provided in the above embodiments, that is, the controller in the wind-storage converter executes the power closed-loop control method of the wind-storage converter provided in the above embodiments; or the main controller in the wind turbine 400 executes the power closed-loop control method of the wind-storage converter provided in the above embodiments. In practical applications, the choice can be made according to the specific situation, and no specific limitation is made here.

[0109] This embodiment also provides another implementation of the power generation system, which is as follows: Figure 11 ( Figure 11 The specific structure of the wind-storage converter 200 is not shown in the image. Figure 10 In addition, it also includes: Energy Storage System 500.

[0110] If the controller in the wind-storage converter executes the power closed-loop control method of the wind-storage converter as provided in the above embodiments, the connection relationship of the energy storage system has been described in detail in the above embodiments and will not be repeated here.

[0111] If the main controller in the wind turbine 400 executes the power closed-loop control method of the wind-storage converter as provided in the above embodiment, the connection port of the energy storage system is connected to: the second side of the DC-DC converter module in the wind-storage converter, or the DC side of the AC-DC converter module in the wind-storage converter.

[0112] This embodiment provides yet another implementation of the power generation system, the specific structure of which is as follows: Figure 12 As shown, in Figure 10 In addition, it also includes: Energy Storage System 500 and Photovoltaic System 600.

[0113] If the controller in the wind-storage converter executes the power closed-loop control method of the wind-storage converter as provided in the above embodiments, the connection relationship between the energy storage system and the photovoltaic system has been described in detail in the above embodiments, and will not be repeated here.

[0114] If the main controller in the wind turbine 400 executes the power closed-loop control method of the wind-storage converter as provided in the above embodiment, the connection port of the energy storage system is connected to: the second side of the DC-DC converter module in the wind-storage converter, or the DC side of the AC-DC converter module in the wind-storage converter; the connection port of the photovoltaic system is connected to: the second side of the DC-DC converter module in the wind-storage converter, or the DC side of the AC-DC converter module in the wind-storage converter.

[0115] The above are only three specific implementations of the power generation system. In practical applications, there are other implementations, including but not limited to these. No specific limitation is made here. The implementation can be determined according to the specific circumstances, and all are within the protection scope of this application.

[0116] The features described above in the disclosed embodiments can be substituted or combined with each other, enabling those skilled in the art to implement or use this application. The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Any person skilled in the art can make many possible variations and modifications to the technical solutions of the present invention using the methods and techniques disclosed above, or modify them into equivalent embodiments with equivalent changes, without departing from the scope of the present invention. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the present invention's technical solutions still fall within the protection scope of the present invention.

Claims

1. A power closed-loop control method for a wind-storage converter, characterized in that, The wind-storage converter includes: a DC-DC converter module and / or an AC-AC converter module, wherein the first side of the DC-DC converter module is connected to the DC bus in the wind-storage converter, and the AC side of the AC-AC converter module is connected to the generator side or the grid side of the wind-storage converter; the power closed-loop control method includes: The DC transmission power of the DC-DC converter and / or the AC transmission power of the AC-AC converter are determined based on the current and voltage of the DC-DC converter and / or the current and voltage of the AC-AC converter. Using the grid-connected power of the wind-storage converter, as well as the DC transmission power and / or the AC transmission power, the actual value of the output power of the wind turbine connected to the wind-storage converter is determined. Determine whether the actual value of the output power is greater than the given value of the output power; If the actual value of the output power is greater than the given value of the output power, then the grid-connected power is reduced; If the actual value of the output power is less than the given value of the output power, then the grid-connected power is increased.

2. The power closed-loop control method for a wind-storage converter according to claim 1, characterized in that, If the transmission direction of the DC-DC converter or the AC-DC converter is: flowing into the wind-storage converter, then when determining the actual value of the output power, the DC transmission power or the AC transmission power is subtracted from the grid-connected power.

3. The power closed-loop control method for a wind-storage converter according to claim 1, characterized in that, If the transmission direction of the DC-DC converter or the AC-DC converter is outflow from the wind-storage converter, then when determining the actual value of the output power, the DC transmission power or the AC transmission power is added to the grid-connected power.

4. The power closed-loop control method for a wind-storage converter according to claim 1, characterized in that, Before determining whether the actual value of the output power is greater than the given value of the output power, the method further includes: Determine whether the absolute value of the difference between the actual value of the output power and the given value of the output power is greater than the hysteresis threshold; If the absolute value is greater than the hysteresis threshold, then the step of determining whether the actual value of the output power is greater than the given value of the output power is performed.

5. A wind-storage converter, characterized in that, include: The system includes a machine-side conversion module, a grid-side conversion module, a first controller, a first current and voltage detection module, and a DC-DC conversion module and / or an AC-DC conversion module; wherein: The AC side of the generator-side conversion module is connected to the generator in the wind turbine, and the AC side of the grid-side conversion module is connected to the power grid. The DC side of the machine-side conversion module is connected to the DC side of the grid-side conversion module via a DC bus. The first side of the DC-DC converter module is connected to the DC bus; The AC side of the AC converter module is connected to either the AC side of the machine-side converter module or the AC side of the network-side converter module. The detection terminal of the first current and voltage detection module is located on the AC side of the grid-side conversion module, and the output terminal of the first current and voltage detection module is connected to the first controller. The turbine-side converter module, the grid-side converter module, the DC-DC converter module, the main controller of the wind turbine generator, and the DC-DC converter module and / or the AC-DC converter module are all controlled by the first controller, which is used to execute the power closed-loop control method of the wind-storage converter as described in any one of claims 1 to 4.

6. The wind-storage converter according to claim 5, characterized in that, The second side of the DC-DC converter module is connected to: the connection port of the energy storage system and / or the connection port of the photovoltaic system; The DC side of the AC converter module is connected to: the connection port of the energy storage system and / or the connection port of the photovoltaic system.

7. The wind-storage converter according to claim 5 or 6, characterized in that, Also includes: A second controller and a second current / voltage detection module and / or a third current / voltage detection module; wherein: The detection terminal of the second current and voltage detection module is located on the first side of the DC-DC converter module, and the detection terminal of the third current and voltage detection module is located on the AC side of the AC-DC converter module. The output terminals of the second current and voltage detection module and the third current and voltage detection module are both connected to the second controller, and the second controller is communicatively connected to the first controller.

8. The wind-storage converter according to claim 7, characterized in that, The second controller and the first controller are integrated into one controller.

9. The wind-storage converter according to claim 7, characterized in that, The current and voltage detection module includes a voltage sensor and a current sensor.

10. The wind-storage converter according to claim 5 or 6, characterized in that, If the generator is a doubly-fed generator, then the wind-storage converter further includes: a stator-side switch; wherein: One end of the stator-side switch is connected to the stator of the generator, and the other end of the stator-side switch is connected to the AC side of the grid-side conversion module.

11. A power generation system, characterized in that, include: Wind turbine generators, transformers, and wind-storage converters; among which: The wind-storage converter is connected to the wind turbine generator on the turbine side, the wind-storage converter is connected to the primary side of the transformer on the grid side, and the transformer is connected to the power grid on the secondary side. The wind-storage converter is the wind-storage converter as described in any one of claims 5 to 10, or the main controller in the wind turbine is used to execute the power closed-loop control method of the wind-storage converter as described in any one of claims 1 to 4.

12. The power generation system according to claim 11, characterized in that, Also includes: Energy storage system, or energy storage system and photovoltaic system.

13. The power generation system according to claim 12, characterized in that, When the main controller is used to execute the power closed-loop control method of the wind-storage converter: The connection port of the energy storage system is connected to: the second side of the DC-DC converter module in the wind-storage converter, or the DC side of the AC-DC converter module in the wind-storage converter; The connection port of the photovoltaic system is connected to: the second side of the DC conversion module in the wind-storage converter, or the DC side of the AC conversion module in the wind-storage converter.

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