Wind power converter with multiple rectifiers

Abstract

The invention provides a wind power converter with multiple rectifiers. The wind power converter comprises a plurality of machine side filtering assemblies, a plurality of rectifiers, a plurality of inverters and a plurality of grid side filtering assemblies. The input ends of the multiple machine side filtering assemblies are connected with the output end of the draught fan, and the output ends of the multiple machine side filtering assemblies are connected with the input ends of the multiple rectifiers in a one-to-one correspondence mode. The output ends of the plurality of rectifiers are connected with the input ends of the plurality of inverters; the output ends of the plurality of inverters are connected with the input ends of the plurality of network side filtering assemblies in a one-to-one correspondence manner; the output ends of the plurality of grid-side filtering assemblies are connected with the input end of the power grid. According to the technical scheme, the output power of the draught fan is improved, when one assembly is cut off due to faults, the draught fan keeps grid-connected operation in a power reduction mode, and the redundancy function is achieved.

Description

Technical Field

[0001] The present application relates to the field of wind power generation, and in particular to a multi-rectifier wind power converter. Background Art

[0002] In recent decades, the research and application of modern wind power generation systems have been mainly based on low-voltage wind turbines. In recent years, with the explosive growth of large-scale wind farm grid-connected capacity, the single-unit capacity of wind turbines has also been increasing, approaching the ten-megawatt level. At the same time, the single-tube capacity of IGBT, a commercialized power electronic active device in the field of low-voltage wind turbine converters, is limited and cannot meet the needs of rapid growth. When a component fails, it will shut down, resulting in a low grid-connected power of the wind power generation system. Therefore, it is urgent to propose a solution that can increase the grid-connected power of wind power generation systems. Summary of the invention

[0003] The present application provides a multi-rectifier wind power converter to at least solve the technical problem of low grid-connected power of a wind power generation system.

[0004] The first embodiment of the present application provides a multi-rectifier wind power converter, the wind power converter comprising: a plurality of machine-side filter components, a plurality of rectifiers, a plurality of inverters, and a plurality of grid-side filter components;

[0005] The input ends of the plurality of machine-side filter assemblies are all connected to the output ends of the fans, and the output ends of the plurality of machine-side filter assemblies are connected to the input ends of the plurality of rectifiers in a one-to-one correspondence;

[0006] The output ends of the plurality of rectifiers are connected to the input ends of the plurality of inverters;

[0007] The output ends of the plurality of inverters are connected to the input ends of the plurality of grid-side filter components in a one-to-one correspondence;

[0008] The output ends of the multiple grid-side filter components are all connected to the input end of the power grid.

[0009] Preferably, the output ends of the plurality of rectifiers are connected to form an independent output end;

[0010] The input ends of the multiple inverters are connected to form an independent input end;

[0011] The independent output terminals of the plurality of rectifiers are connected to the independent input terminals of the plurality of inverters.

[0012] Furthermore, the plurality of machine-side filter components are used to filter the electric energy output by the fan;

[0013] The multiple rectifiers are used to convert the filtered electric energy into direct current electric energy;

[0014] The plurality of inverters are used to convert the DC power into AC power;

[0015] The multiple grid-side filter components are used to filter the electric energy input into the grid.

[0016] Furthermore, the number of the multiple machine-side filter components, the multiple rectifiers, the multiple inverters, and the multiple grid-side filter components is the same.

[0017] Furthermore, the number of the rectifiers is determined based on the capacity of a single rectifier and the capacity of the fan.

[0018] Furthermore, the calculation formula for the number of rectifiers is as follows:

[0019]

[0020] Where N is the number of rectifiers, P is the capacity of the fan, and P s is the capacity of a single rectifier.

[0021] The technical solution provided by the embodiments of the present application brings at least the following beneficial effects:

[0022] The present application proposes a multi-rectifier wind power converter, which includes: multiple machine-side filter components, multiple rectifiers, multiple inverters, and multiple grid-side filter components; the input ends of the multiple machine-side filter components are all connected to the output ends of the wind turbine, and the output ends of the multiple machine-side filter components are connected one-to-one with the input ends of the multiple rectifiers; the output ends of the multiple rectifiers are connected to the input ends of the multiple inverters; the output ends of the multiple inverters are connected one-to-one with the input ends of the multiple grid-side filter components; the output ends of the multiple grid-side filter components are all connected to the input ends of the power grid. The technical solution proposed in the present application realizes the improvement of the output power of the wind turbine. When a component is removed due to a fault, the wind turbine maintains grid-connected operation by reducing power, and has a redundancy function.

[0023] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0025] Figure 1 A block diagram of a multi-rectifier wind power converter provided according to an embodiment of the present application;

[0026] Figure 2A schematic diagram of a multi-rectifier wind power converter having three rectifiers according to an embodiment of the present application;

[0027] Figure 3 A structural diagram of a wind turbine and a power grid connected to a multi-rectifier wind power converter according to an embodiment of the present application;

[0028] Reference numerals

[0029] Machine-side filter component 1, rectifier 2, inverter 3, grid-side filter component 4, wind turbine 101 and grid 102. DETAILED DESCRIPTION

[0030] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0031] The present application proposes a multi-rectifier wind power converter, which includes: multiple machine-side filter components, multiple rectifiers, multiple inverters, and multiple grid-side filter components; the input ends of the multiple machine-side filter components are all connected to the output ends of the wind turbine, and the output ends of the multiple machine-side filter components are connected one-to-one with the input ends of the multiple rectifiers; the output ends of the multiple rectifiers are connected to the input ends of the multiple inverters; the output ends of the multiple inverters are connected one-to-one with the input ends of the multiple grid-side filter components; the output ends of the multiple grid-side filter components are all connected to the input ends of the power grid. The technical solution proposed in the present application realizes the improvement of the output power of the wind turbine. When a component is removed due to a fault, the wind turbine maintains grid-connected operation by reducing power, and has a redundancy function.

[0032] A multi-rectifier wind power converter according to an embodiment of the present application is described below with reference to the accompanying drawings.

[0033] Embodiment 1

[0034] Figure 1 A flow chart of a multi-rectifier wind power converter provided according to an embodiment of the present application is shown in FIG. Figure 1 As shown, the wind power converter includes: a plurality of machine-side filter components 1, a plurality of rectifiers 2, a plurality of inverters 3, and a plurality of grid-side filter components 4;

[0035] The input ends of the multiple machine-side filter components 1 are all connected to the output end of the wind turbine 101, and the output ends of the multiple machine-side filter components 1 are connected to the input ends of the multiple rectifiers 2 in a one-to-one correspondence;

[0036] The output ends of the multiple rectifiers 2 are connected to the input ends of the multiple inverters 3;

[0037] The output ends of the plurality of inverters 3 are connected to the input ends of the plurality of grid-side filter components 4 in a one-to-one correspondence;

[0038] The output ends of the plurality of grid-side filter components 4 are all connected to the input end of the power grid 102 .

[0039] It should be noted that if Figure 2 As shown, the output ends of the multiple rectifiers 2 are connected to form an independent output end;

[0040] The input ends of the multiple inverters 3 are connected to form an independent input end;

[0041] The independent output ends of the plurality of rectifiers 2 are connected to the independent input ends of the plurality of inverters 3 .

[0042] It should be noted that Figure 2 This is a schematic diagram of a multi-rectifier wind power converter in accordance with the present embodiment, in which there are three rectifiers 2 , and does not limit the structure of the multi-rectifier wind power converter in accordance with the present application.

[0043] It should be noted that the multiple machine-side filter components 1 are used to filter the electric energy output by the wind turbine, such as filtering the machine-side voltage and current to improve the waveform quality.

[0044] The multiple rectifiers 2 are used to convert the filtered electric energy into direct current electric energy, such as converting the machine-side alternating current into direct current, so as to facilitate the subsequent electric energy conversion of the inverter 3 .

[0045] The multiple inverters 3 are used to convert the DC power into AC power, such as converting DC power into AC power that is fed into a power grid;

[0046] The plurality of grid-side filter components 4 are used to filter the electric energy input into the grid, such as filtering the grid-side voltage and current to improve the quality of the grid-connected waveform.

[0047] In the embodiment of the present disclosure, the number of the plurality of machine-side filter assemblies 1, the plurality of rectifiers 2, the plurality of inverters 3, and the plurality of grid-side filter assemblies 4 is the same.

[0048] It should be noted that the number of the rectifiers 2 is determined based on the capacity of a single rectifier 2 and the capacity of the fan 101 .

[0049] The calculation formula for the number of rectifiers is as follows:

[0050]

[0051] Where N is the number of rectifiers, P is the capacity of the fan, and P s is the capacity of a single rectifier.

[0052] For example, Figure 3 The figure shows a schematic diagram of a multi-rectifier wind power converter connected to a wind turbine 101 and a power grid 102 when N is equal to 3. Three machine-side filter components 1, three rectifiers 2, three inverters 3, and three grid-side filter components 4 constitute the wind power converter, and the power passing through the three identical components is the same. Therefore, the proposed multi-rectifier wind power converter achieves an increase in the output power of the wind turbine. When a component is removed due to a fault, the wind turbine maintains grid-connected operation by reducing power, so it has a redundant function.

[0053] It should be noted that the multi-rectifier wind power converter provided in this embodiment has the following advantages:

[0054] 1. The output power of the wind turbine is increased by using multiple distributed small-power converters; 2. The reliability problems such as voltage and current equalization caused by series and parallel connection of power semiconductor devices are avoided; 3. When the converter fails, the wind turbine can remain connected to the grid and thus has redundancy.

[0055] In summary, the multi-rectifier wind power converter proposed in this embodiment improves the output power of the wind turbine. When a component is removed due to a fault, the wind turbine maintains grid-connected operation by reducing power, and has a redundancy function.

[0056] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0057] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0058] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A multi-rectifier wind power converter, characterized in that: The wind power converter comprises: a plurality of machine-side filter components, a plurality of rectifiers, a plurality of inverters, and a plurality of grid-side filter components; The input ends of the plurality of machine-side filter assemblies are all connected to the output ends of the fans, and the output ends of the plurality of machine-side filter assemblies are connected to the input ends of the plurality of rectifiers in a one-to-one correspondence; The output ends of the plurality of rectifiers are connected to the input ends of the plurality of inverters; The output ends of the plurality of inverters are connected to the input ends of the plurality of grid-side filter components in a one-to-one correspondence; The output ends of the multiple grid-side filter components are all connected to the input end of the power grid.

2. The wind power converter according to claim 1, characterized in that: The output ends of the multiple rectifiers are connected to form an independent output end; The input ends of the multiple inverters are connected to form an independent input end; The independent output terminals of the plurality of rectifiers are connected to the independent input terminals of the plurality of inverters.

3. The wind power converter according to claim 2, characterized in that: The multiple machine-side filter components are used to filter the electric energy output by the fan; The multiple rectifiers are used to convert the filtered electric energy into direct current electric energy; The plurality of inverters are used to convert the DC power into AC power; The multiple grid-side filter components are used to filter the electric energy input into the grid.

4. The wind power converter according to claim 3, characterized in that: The number of the multiple machine-side filter components, the multiple rectifiers, the multiple inverters, and the multiple grid-side filter components is the same.

5. The wind power converter according to claim 4, characterized in that: The number of the rectifiers is determined based on the capacity of a single rectifier and the capacity of the fan.

6. The wind power converter according to claim 4, characterized in that: The calculation formula for the number of rectifiers is as follows: Where N is the number of rectifiers, P is the capacity of the fan, and P s is the capacity of a single rectifier.

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