Wind power variable pitch system and wind generating set using same

Abstract

The utility model provides a wind power variable pitch system which at least comprises a variable pitch control system which is connected with a fan master control system of a wind generating set and is responsible for signal transmission and variable pitch action control; the variable-pitch driver receives an instruction from the variable-pitch control system and drives a variable-pitch motor to perform variable-pitch action on fan blades; and the standby power supply receives an instruction from the variable pitch control system, supplies power to the variable pitch driver and enables the variable pitch driver to perform variable pitch action, and is characterized in that the standby power supply is provided with at least one nickel-hydrogen battery pack and a battery management system (BMS).

Description

Technical Field

[0001] The utility model relates to a wind power variable pitch system and a wind turbine generator set using the same, and in particular to a wind power variable pitch system suitable for use in offshore high-power wind turbine generator sets. Background Art

[0002] The wind turbine pitch system (referred to as wind turbine pitch system) can adjust the blade angle and control the rotation of the blades in real time according to changes in wind speed, thereby ensuring that the wind turbine achieves power balance at the rated wind speed and ensuring the safety of the entire machine under extreme weather conditions. It has the advantages of improving wind power generation efficiency and extending the life of wind turbines, and plays a very important role in the stable and efficient operation of the unit.

[0003] like Figure 1 As shown, the wind turbine pitch control system (1) represented by the dotted box mainly includes: a pitch control system (2), which is connected to the wind turbine main control system (3) of the wind turbine generator set through a communication line and is responsible for signal transmission and processing and controlling the pitch control action; a pitch drive (4), which receives instructions from the pitch control system (2) and drives the pitch motor (5), and the pitch motor (5) performs specific pitch control actions on the wind blades (6); and a super capacitor (7) as a backup power supply: according to the instructions of the pitch control system (2), when the main power supply fails, it provides power to the pitch drive (4) to enable it to perform pitch control operations.

[0004] In existing wind turbine pitch control systems, a supercapacitor (7) is usually used as a backup power source. When the grid inputs power and the wind turbine is in operation, the supercapacitor (7) is charged by a charger, and charging stops when the charge reaches the rated voltage. When the environment changes and the wind turbine is in emergency operation, the pitch control system (2) issues a command requiring emergency pitch control. At this time, the supercapacitor (7) starts to discharge, and the pitch drive (4) drives the pitch motor (5) to control the blades (6) to feather, so that the blades reach a suitable angle or the wind turbine is shut down safely.

[0005] However, problems exist in the existing technology: supercapacitors have low energy density and fast self-discharge, and the voltage loss every two weeks at room temperature may be as high as 60%; the capacity is released instantly, and when fully charged, it can only meet the pitch change requirement once, making it unsuitable for use in offshore high-power wind turbines; in addition, the high voltage and high capacity requirements of high-power wind turbines require multiple supercapacitors to be connected in series, which makes the overall volume of the wind power pitch change system larger, heavier, and the price index doubled, significantly increasing the cost. Utility Model Content

[0006] The purpose of the utility model is to provide a wind power pitch control system suitable for offshore high-power wind turbine generator sets, and a wind turbine generator set using the same.

[0007] The wind turbine pitch control system of the present invention at least includes:

[0008] The pitch control system is connected to the wind turbine main control system of the wind turbine generator set and is responsible for signal transmission and controlling the pitch action;

[0009] A pitch driver receives instructions from the pitch control system and drives the pitch motor to perform pitching on the wind blades; and

[0010] The backup power supply receives instructions from the pitch control system and provides power to the pitch drive to enable it to perform pitch control.

[0011] Its characteristics are:

[0012] The backup power supply includes at least one nickel-metal hydride battery pack and a battery management system (BMS).

[0013] Preferably, there are multiple nickel-metal hydride battery packs, and two adjacent nickel-metal hydride battery packs are electrically connected in series or in parallel.

[0014] Preferably, the plurality of nickel-metal hydride battery packs share the battery management system (BMS).

[0015] Preferably, the battery management system (BMS) is connected to the wind turbine main control system.

[0016] Preferably, the nickel-metal hydride battery pack includes a battery block, and an upper shell and a lower shell for accommodating the battery block.

[0017] The battery block is formed by connecting a plurality of nickel-metal hydride cells in parallel or in series.

[0018] The positive and negative electrodes of the multiple nickel-hydrogen batteries are respectively connected to the positive terminal and negative terminal provided on the lower shell, and the sensors and protection elements of the multiple nickel-hydrogen batteries are respectively connected to the communication terminals provided on the lower shell.

[0019] Preferably, the backup power supply comprises at least a first battery group and a second battery group, the first battery group is composed of a plurality of nickel-metal hydride battery groups connected in series, and the second battery group is composed of a plurality of nickel-metal hydride battery groups connected in series. The first battery group and the second battery group are connected in series or in parallel and share the battery management system (BMS).

[0020] Preferably, the wind power pitch control system is used for high-power wind turbine generator sets.

[0021] Preferably, after the nickel-metal hydride battery pack is fully charged once, the pitch drive can perform multiple pitch actions.

[0022] The wind turbine generator set of the present invention is characterized in that it comprises any of the wind turbine pitch control systems described above.

[0023] Preferably, the power of the wind turbine generator set is greater than 10 megawatts.

[0024] Utility model effect

[0025] The wind turbine pitch control system of this invention uses a nickel-metal hydride (NiMH) battery pack as a backup power source. Due to the high energy density and slow self-discharge of the NiMH battery pack, the problem of rapid self-discharge of supercapacitors can be solved. Multiple NiMH battery packs can be connected in series to increase capacity, and a single full charge can meet multiple pitch control requirements, making it particularly suitable for offshore high-power wind turbines. Furthermore, the NiMH battery pack is small in size and light in weight, effectively reducing the installation cost of the wind turbine pitch control system. Furthermore, the NiMH battery pack serving as a backup power source can also be equipped with a battery management system (BMS), which can monitor the battery status in a timely manner and easily implement remote diagnosis of the NiMH battery pack on land. It can also perform checks on battery aging and make early predictions about battery life, thereby better understanding the battery status and reducing maintenance difficulty and costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram showing the composition of a wind turbine pitch control system in the prior art.

[0027] Figure 2 It is a schematic diagram showing the composition of the wind turbine pitch control system of the present invention.

[0028] Figure 3 It is a schematic diagram showing the structure of the nickel-hydrogen battery pack in the wind turbine pitch control system of the present invention.

[0029] Figure 4 Schematic diagram showing a backup power supply of an example of a wind turbine pitch control system according to the present invention.

[0030] Figure 5 It is a schematic diagram showing a backup power supply of another example of the wind turbine pitch control system of the present invention. DETAILED DESCRIPTION

[0031] The specific form of the wind turbine pitch control system of the present invention will be described below with reference to the accompanying drawings.

[0032] Figure 2 3 is a schematic diagram showing the composition of the wind turbine pitch control system of the present invention. In the figure, the portion surrounded by the dotted line frame represents the main component modules of the wind turbine pitch control system.

[0033] like Figure 2As shown, the wind turbine pitch control system (1) of the present invention comprises at least: a pitch control system (2), which is connected to the wind turbine main control system (3) of the wind turbine generator set via a communication line and is responsible for signal transmission and controlling the pitch control action; a pitch drive (4), which receives instructions from the pitch control system (2) via the communication line and drives the pitch motor (5) to perform the pitch control action on the wind blade (6); and a backup power supply (8), which receives instructions from the pitch control system (2) and provides power to the pitch drive (4) to perform the pitch control action, and is characterized in that the backup power supply (8) is provided with at least one nickel-metal hydride battery pack (9) and a battery management system (BMS).

[0034] The wind turbine pitch control system (1) of the present invention is characterized in that a nickel-metal hydride battery pack (9) is used instead of a traditional supercapacitor as a backup power source. Compared with supercapacitors, nickel-metal hydride battery packs have high energy density and slow self-discharge. Under normal temperature and full charge, the annual voltage loss is about 10%. Therefore, only one full charge can meet multiple pitch control requirements over a long period of time, and is particularly suitable for offshore high-power wind turbines.

[0035] In addition, a plurality of nickel-metal hydride battery packs (9) are connected in series or in parallel in the backup power supply, and the number of battery packs connected in series or in parallel can be adjusted according to the specific pitch change requirements of the wind turbine.

[0036] The wind turbine pitch control system of the present invention is also characterized in that a battery management system (BMS) is used in the backup power supply (8). The battery management system (BMS) is connected to the wind turbine main control system and collects and monitors the working status, battery temperature, discharge time, etc. of the nickel-hydrogen battery pack through a communication harness, and performs two-way information feedback and transmission.

[0037] Figure 3 It is a schematic diagram showing the structure of a nickel-hydrogen battery pack (9) in the wind power pitch control system of the utility model.

[0038] like Figure 3 As shown, the specific structure of the nickel-hydrogen battery pack of the utility model includes: a battery block (10), and an upper shell (11) and a lower shell (12) for accommodating the battery block (10).

[0039] The battery block (10) is formed by electrically connecting a plurality of nickel-hydrogen cells in parallel or in series to form a block shape. The lower shell (12) is in the shape of a bottom frame, and the upper shell (11) is in the shape of a flat cover. The upper shell (11) is fastened to the lower shell (12) by screws (13) to form a cavity for accommodating the battery block (10).

[0040] The positive and negative electrodes of the nickel-metal hydride cells constituting the battery block (10) are connected via bus bars and are respectively connected to a positive terminal (14) and a negative terminal (15) provided on the lower housing (12). Sensors and protective elements for detecting battery temperature, etc., provided in each nickel-metal hydride cell, are connected to a communication terminal (16) provided on the lower housing via respective wires.

[0041] In the backup power supply (8) of the wind turbine pitch control system (1) of the present invention, there may be one or more nickel-hydrogen battery packs (9), and two adjacent nickel-hydrogen battery packs (9) are electrically connected in series or in parallel.

[0042] Figure 4 This is a schematic diagram showing a backup power supply of an example of a wind turbine pitch control system (1) of the present invention.

[0043] like Figure 4 As shown, the backup power supply (8) includes a plurality of nickel-hydrogen battery packs (9) connected in series, and a battery management system (BMS) module located above these battery packs. The positive terminals and negative terminals of the plurality of nickel-hydrogen battery packs (9) are connected respectively through a series guide plate (21), and are further connected to a positive lead (24) and a negative lead (25) located outside the power supply. The communication harness (26) derived from the communication terminal of each nickel-hydrogen battery pack (9) is respectively connected to the BMS located above, and the battery temperature, discharge time, etc. of each nickel-hydrogen battery pack collected are fed back to the wind turbine main control system and pitch control system through the BMS.

[0044] Figure 4 In the embodiment, multiple nickel-metal hydride battery packs (9) are connected to each other in series, but are not limited thereto. They can also be connected in parallel as needed, or multiple nickel-metal hydride battery packs can be connected to each other in a combination of series and parallel connections. These battery packs share a battery management system (BMS).

[0045] Figure 5 It is a schematic diagram showing a backup power supply of another example of the wind turbine pitch control system of the present invention.

[0046] like Figure 5 As shown, the backup power supply (8) of the wind turbine pitch control system of the present invention comprises at least a first battery group and a second battery group, wherein the first battery group is composed of a plurality of nickel-hydrogen battery groups (9a) connected in series, and the second battery group is composed of a plurality of nickel-hydrogen battery groups (9b) connected in series, and the first battery group and the second battery group are connected in parallel and share a battery management system (BMS).

[0047] Figure 5In the embodiment, the first battery group and the second battery group are connected in parallel, but are not limited thereto. They can also be connected in series, or in a combination of series and parallel connections, as needed. These battery groups share a battery management system (BMS).

[0048] The wind turbine pitch control system of the present invention adopts a nickel-metal hydride battery pack (NiMH) as a backup power source. Since the energy density of the nickel-metal hydride battery pack is higher than that of the supercapacitor and the self-discharge is slower, the problem of fast self-discharge of the supercapacitor can be effectively solved; multiple groups of nickel-metal hydride battery packs can be flexibly connected in parallel or series, and the capacity of the backup battery can be easily increased while meeting the voltage requirements. Only one full charge can provide multiple pitch control powers for the wind turbine, which is more suitable for wind turbines with higher output power (for example, more than 16 megawatts); in addition, the nickel-metal hydride battery pack is small in size and lighter in weight at the same volume, which effectively reduces the cost of the wind turbine pitch control system. In addition, the performance reliability of the nickel-metal hydride battery itself in a wide temperature range from low temperature to high temperature is particularly suitable for offshore high-power wind turbines.

[0049] Furthermore, the nickel-metal hydride battery pack used as a backup power source can also be equipped with a battery management system (BMS), which can monitor the battery status in a timely manner and easily implement remote temperature control and full-charge disconnection of the nickel-metal hydride battery pack on land; it can also perform aging inspections on the battery and make early predictions of the battery life, so as to better understand the battery status and reduce maintenance difficulty and costs.

[0050] The present invention also provides a wind turbine generator set comprising the above-mentioned wind turbine pitch control system, characterized in that the power of the wind turbine generator set is above 10 megawatts (MW), preferably above 16 MW.

[0051] In the wind turbine generator set of the present invention, the nickel-hydrogen battery pack with high energy density and slow self-discharge can replace the existing supercapacitor through parallel replacement, thereby providing a future-oriented and more adaptable offshore high-power wind turbine.

[0052] The wind turbine pitch control system and wind turbine generator set of the present invention are described above through the accompanying drawings and specific implementation methods, but the present invention is not limited to the above-mentioned specific implementation methods. Various deformations or element changes can be made without departing from the scope of the main purpose of the present invention, and these deformations or element changes are also included in the protection scope of the present invention.

Claims

1. A wind turbine pitch control system, comprising at least: The pitch control system is connected to the wind turbine main control system of the wind turbine generator set and is responsible for signal transmission and controlling the pitch action; A pitch driver receives instructions from the pitch control system and drives the pitch motor to perform pitching on the wind blades; and The backup power supply receives instructions from the pitch control system and provides power to the pitch drive to enable it to perform pitch control. Its characteristics are: The backup power supply includes at least one nickel-metal hydride battery pack and a battery management system (BMS).

2. The wind turbine pitch control system according to claim 1, characterized in that: There are multiple nickel-hydrogen battery packs, and two adjacent nickel-hydrogen battery packs are electrically connected in series or in parallel.

3. The wind turbine pitch control system according to claim 2, characterized in that: The plurality of nickel-metal hydride battery packs share the battery management system (BMS).

4. The wind turbine pitch control system according to claim 1 or 2, characterized in that: The battery management system (BMS) is connected to the wind turbine main control system.

5. The wind turbine pitch control system according to claim 1 or 2, characterized in that: The nickel-metal hydride battery pack includes a battery block, and an upper shell and a lower shell for accommodating the battery block. The battery block is formed by connecting a plurality of nickel-metal hydride cells in parallel or in series. The positive and negative electrodes of the multiple nickel-hydrogen batteries are respectively connected to the positive terminal and negative terminal provided on the lower shell, and the sensors and protection elements of the multiple nickel-hydrogen batteries are respectively connected to the communication terminals provided on the lower shell.

6. The wind turbine pitch control system according to claim 1 or 2, characterized in that: The backup power supply includes at least a first battery group and a second battery group. The first battery group is composed of multiple nickel-metal hydride battery groups connected in series, and the second battery group is composed of multiple nickel-metal hydride battery groups connected in series. The first battery group and the second battery group are connected in series or in parallel and share the battery management system (BMS).

7. The wind turbine pitch control system according to claim 1 or 2, characterized in that: The wind power pitch control system is used for high-power wind turbine generator sets.

8. The wind turbine pitch control system according to claim 1 or 2, characterized in that: After the nickel-metal hydride battery pack is fully charged once, the pitch drive can perform multiple pitch changing actions.

9. A wind turbine generator set, characterized in that: The wind turbine pitch control system comprises the wind turbine pitch control system according to any one of claims 1 to 8.

10. The wind turbine generator set according to claim 9, characterized in that: The power of the wind turbine generator set is above 10 megawatts.

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