An integrated system of hexagonal wind tower and vertical axis generator and a control method thereof

Abstract

The application discloses a kind of hexagonal wind tower and vertical axis generator integrated system and its control method, including the hexagonal wind tower frame of peripheral support structure, inner auxiliary column and radial straight plate wind gathering board, and the multiple layers vertical axis wind turbine group of layered installation in the central region of tower frame.It is characterized by: each layer generator set and each layer independently configured inverter one-to-one corresponding connection, each layer inverter independently executes MPPT control, and independently optimizes working point according to the layer wind speed sensor data;Each layer inverter output is centrally converged after being converged by current collecting device, and is uniformly connected to grid;When any layer fails, the inverter of this layer is automatically disconnected, and the rest of each layer continues normal operation;Interlayer cable is wired along the inside of inner auxiliary column.The application realizes the technical effects of layered independent power generation, accurate optimization of each layer MPPT, current collection grid connection reduces equipment cost, fault isolation improves availability.

Description

Technical Field

[0001] This invention relates to the field of wind power generation technology, specifically to an integrated system of a hexagonal wind concentrator tower and a vertical axis generator, and its control methods for layered independent power generation, MPPT control of each layer, and grid connection. Background Technology

[0002] Vertical axis wind turbines (VAWTs) have potential applications in urban areas and low-wind-speed regions due to their advantages such as not requiring wind contact, simple structure, and low noise. However, traditional VAWTs have low power generation efficiency, and in the atmospheric boundary layer where wind speed distribution is uneven, it is difficult for a single generator to be independently optimized for wind speeds at different altitudes.

[0003] To improve power generation efficiency, existing technologies have proposed various wind concentrator schemes, including hexagonal tower wind concentrators, deflecting wind concentrators, and curved guide walls. However, existing wind concentrator tower schemes share the following common drawbacks: Single-layer high-power generation cannot match wind shear: Wind speed in the atmospheric boundary layer increases with altitude (wind shear effect), and wind speeds vary significantly at different altitudes. Existing wind concentrator tower solutions typically use a single high-power generator to cover the entire tower height, which cannot perform independent maximum power point tracking (MPPT) for the actual wind speed at different altitudes, resulting in low overall power generation efficiency.

[0004] Single point of failure risk: failure of a single high-power generator can cause the entire tower to shut down, resulting in poor system reliability and high maintenance costs.

[0005] Redundancy of grid-connected equipment: In traditional solutions, each wind turbine requires an independent grid-connection interface device for independent grid connection, which increases system cost and complexity.

[0006] Unable to adapt to differences in wind speed between layers: Even with stratified power generation, existing technologies have not achieved independent MPPT control and fault isolation for each layer, and there is coupling interference between layers. Summary of the Invention

[0007] Purpose of the invention: To provide an integrated system and control method for a hexagonal wind concentrator tower and a vertical axis generator, achieving the technical effects of layered independent power generation, independent MPPT for each layer, grid connection, and fault isolation.

[0008] Technical solution: An integrated system of a hexagonal wind concentrator and a vertical axis generator, comprising: The outer support structure is arranged in a regular hexagonal shape, including 6 outer main columns distributed along the vertices of the regular hexagon (1). The internal support structure includes 6 inner auxiliary columns (2), which are evenly distributed along the inner distribution circle with the center of the outer main column (1); Six wind-gathering plates (3) are arranged in a radial direction, extending from an outer main column (1) to the corresponding inner auxiliary column (2), forming six radial wind-gathering channels. The hierarchical independent power generation architecture includes at least two layers of vertical axis wind turbine generators (6). The generators (6) are installed at different heights in the central area, and each generator is connected to an inverter (21) configured independently in each layer. The combined grid connection device includes a combined device (22), a step-up transformer (23) and a grid connection interface (24). The output terminals of each inverter (21) are connected to the combined device (22). The electrical energy combined by the combined device (22) is stepped up by the step-up transformer (23) and then connected to the grid through the grid connection interface (24). Each layer has an independent MPPT control unit, including a wind speed sensor (26) and an MPPT controller (25) set on each layer. The wind speed sensor (26) of each layer collects the wind speed data of that layer in real time, and the MPPT controller (25) of each layer independently adjusts the operating point of the inverter (21) of that layer according to the data of the wind speed sensor (26) of that layer.

[0009] A control method for an integrated system includes the following steps: (a) Each layer of wind speed sensor (26) collects wind speed data at its height position in real time; (b) Each layer MPPT controller (25) independently adjusts the operating point of the inverter (21) of the layer based on the wind speed data collected by the wind speed sensor (26) of the layer, so that the power generation system of the layer always operates at the maximum power point; (c) The AC power output by each inverter (21) is transmitted to the combiner device (22) via the circuit breaker (34) of each layer for centralized collection. The collected power is stepped up by the step-up transformer (23) and then connected to the grid through the grid interface (24). (d) When a fault is detected in any layer, the inverter (21) of that layer is automatically disconnected, and the power generation systems of the remaining layers continue to operate normally.

[0010] The core findings of this invention: Layered independent power generation architecture matches wind shear: Wind speed in the atmospheric boundary layer increases with altitude, and wind speed differences at different altitudes are significant. Layered independent power generation architecture enables independent optimization of generator power and operating point for each layer. Each layer can perform independent MPPT tracking for the actual wind speed at that altitude. The bottom layer uses the wind gathering effect of the wind concentrator to compensate for low wind speeds, while the top layer utilizes higher free-flow wind speeds. The overall power generation efficiency is significantly improved compared to single-layer high-power generation.

[0011] Independent MPPT for each layer enables precise optimization: Each layer's MPPT controller independently adjusts the inverter's operating point based on the wind speed sensor data for that layer, unaffected by interference from other layers. The operating points of the bottom and top layers do not affect each other, and each layer can operate at its own maximum power point, achieving precise power optimization.

[0012] Combined grid connection reduces equipment costs: The outputs of inverters on each floor are combined and connected to the grid through a combined grid device, requiring only one step-up transformer and one grid connection interface, which reduces the number and cost of grid-connected equipment.

[0013] Fault isolation improves system availability: When any layer of the power generation system fails, the inverter on that layer automatically disconnects, the layer circuit breaker trips to isolate the faulty layer, and the power generation systems on the remaining layers continue to operate normally. After fault isolation, the system availability is calculated as a proportion of the number of normal layers, which is significantly higher than the risk of a complete tower shutdown under a single-layer scheme.

[0014] Optimized layout of inter-layer cable routing along inner auxiliary column: Inter-layer cable (28) is routed along the inner auxiliary column (2), utilizing the structural space of the inner auxiliary column, without occupying the space of the central power generation area, and at the same time facilitating cable inspection and maintenance.

[0015] Beneficial effects: Improved power generation efficiency: Independent MPPT tracking for each layer matches wind speed distribution at different heights, resulting in an overall power generation efficiency increase of approximately 10% to 20% compared to a single-layer solution.

[0016] Improved system reliability: The fault isolation mechanism ensures that a single-layer failure does not affect the operation of other layers, significantly improving system availability.

[0017] Reduced grid connection costs: The combiner grid connection solution only requires one step-up transformer and one grid connection interface, which reduces the investment cost of grid connection equipment.

[0018] Highly adaptable: It can be expanded to different tower heights (30m-60m) and different numbers of floors (36 floors) to meet the construction needs of different wind resource areas.

[0019] Convenient operation and maintenance: The power generation system on each floor operates independently, and a single-floor fault can be repaired and maintained separately without shutting down the entire tower. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall system integration of the present invention; Figure 2 This is a diagram of the hierarchical independent power generation architecture of the present invention; Figure 3 This is a block diagram of the MPPT control layer of the present invention; Figure 4 This is a schematic diagram of the grid connection of the present invention.

[0021] In the diagram: 1-Outer main column, 2-Inner auxiliary column, 3-Wind concentrator, 6-Generator set, 8-Ring beam, 21-Inverter, 22-Combiner device, 23-Step-up transformer, 24-Grid connection interface, 25-MPPT controller, 26-Wind speed sensor, 27-SCADA monitoring unit, 28-Inter-floor cable, 29-Main circuit breaker, 30-Surge protector, 31-Energy storage device, 32-Communication module, 33-Remote monitoring terminal, 34-Floor circuit breaker. Detailed Implementation

[0022] Example 1: 48m / 4-story system integration An integrated system of a hexagonal wind concentrator and a vertical axis generator, see [link / reference]. Figure 1 , Figure 2 , Figure 3 and Figure 4 .

[0023] Tower structure: The outer supporting structure is arranged in a regular hexagonal shape, with 6 outer main columns (1) evenly distributed along a circle with a radius of R1=9.0m, and the included angle between adjacent columns is 60°. The outer main columns (1) have a diameter of 0.4m and are made of steel pipe concrete structure. There are no continuous walls between the outer main columns (1), forming 6 open air inlets.

[0024] The internal support structure includes 6 inner auxiliary columns (2), which are evenly distributed along a circle with a radius of R2 = 5.15m and an inner-outer diameter ratio of R1 / R2 = 1.75. The inner auxiliary columns (2) have a diameter of 0.3m and are made of BFRP composite material.

[0025] The six wind-gathering plates (3) are radial straight plates, each extending radially from an outer main column (1) to the corresponding inner auxiliary column (2), with a straight segment length L=R1-R2=3.85m. The wind-gathering plates (3) do not produce a deflection angle, and the adjacent wind-gathering plates are distributed at an equal angle of 60°.

[0026] Layered independent power generation architecture: The tower has a total height of 48m, with four layers of vertical axis wind turbine generators (6) installed in the central area. The parameters for each layer are as follows: The sweep radius of each rotor is R_rotor=5.0m, which is less than R2=5.15m, leaving a safety clearance.

[0027] Electrical system connections: See Figure 2 and Figure 4 The electrical connections of each generator set (6) are as follows: L1 layer: Generator → Layer circuit breaker (34) → Inverter (21) → Combiner unit (22) L2 layer: Generator → Layer circuit breaker (34) → Inverter (21) → Combiner unit (22) L3 layer: Generator → Layer circuit breaker (34) → Inverter (21) → Combiner unit (22) L4 layer: Generator → Layer circuit breaker (34) → Inverter (21) → Combiner unit (22) The combined electrical energy output by the combiner device (22) is connected to the power grid in sequence through the main circuit breaker (29), surge protector (30), step-up transformer (23) and grid connection interface (24).

[0028] MPPT control at each level: See Figure 3 Each floor is equipped with an independent wind speed sensor (26) and MPPT controller (25): L1 layer: The wind speed sensor (26-1) collects real-time wind speed data for L1 layer, and the MPPT controller (25-1) independently adjusts the operating point of the inverter (21-1) according to the wind speed of L1 layer. L2 layer: The wind speed sensor (26-2) collects real-time wind speed data of the L2 layer, and the MPPT controller (25-2) independently adjusts the operating point of the inverter (21-2) according to the wind speed of the L2 layer. L3 layer: The wind speed sensor (26-3) collects real-time wind speed data at L3 layer, and the MPPT controller (25-3) independently adjusts the operating point of the inverter (21-3) according to the wind speed at L3 layer. L4 layer: The wind speed sensor (26-4) collects real-time wind speed data at L4 layer, and the MPPT controller (25-4) independently adjusts the operating point of the inverter (21-4) according to the wind speed at L4 layer. Each inverter (21) executes the MPPT algorithm independently and optimizes its operating point independently based on the actual wind speed of that layer, without being disturbed by other layers.

[0029] Inter-floor cable routing: Interlayer cables (28) between each layer are routed along the inner auxiliary column (2), utilizing the structural space of the inner auxiliary column, without occupying the space of the central power generation area, which facilitates the inspection and maintenance of the cables.

[0030] SCADA monitoring and remote monitoring: The SCADA monitoring unit (27) collects all tower operation data, including wind speed, power generation, generator speed, inverter status, and fault information at each floor. The SCADA monitoring unit (27) uploads the data to the remote monitoring terminal (33) through the communication module (32) to realize remote monitoring and operation and maintenance management.

[0031] Energy storage devices: An optional energy storage device (31) can be configured and connected to the DC bus or AC bus of the combiner device (22) to smooth out power fluctuations and provide backup power.

[0032] Control logic: The control method in this embodiment includes the following steps: (a) Each layer of wind speed sensor (26) collects wind speed data at its height position in real time; (b) Each layer MPPT controller (25) independently adjusts the operating point of the inverter (21) of the layer based on the wind speed data collected by the wind speed sensor (26) of the layer, so that the power generation system of the layer always operates at the maximum power point; (c) The AC power output by each inverter (21) is transmitted to the combiner device (22) via the circuit breaker (34) of each layer for centralized collection. The collected power is stepped up by the step-up transformer (23) and then connected to the grid through the grid interface (24). (d) When a fault is detected in any layer, the inverter (21) of that layer is automatically disconnected, the layer circuit breaker (34) trips to isolate the faulty layer, and the power generation systems of the remaining layers continue to operate normally.

[0033] Further over-wind speed protection: When the wind speed of any layer exceeds the rated wind speed of that layer, that layer will independently perform braking or pitch control to reduce the rotation speed of that layer, while the other layers will operate normally.

[0034] Key parameters of Example 1:

[0035] The difference from Example 1 is that the total tower height is 30m, and the three-layer vertical axis wind turbine generators (6) are installed in the central area. The parameters of each layer are as follows: The remaining wind-gathering structure and electrical system parameters are the same as in Example 1.

[0036] The difference from Example 1 is that the total tower height is 60m, and the 5-layer vertical axis wind turbine generator sets (6) are installed in the central area. The parameters of each layer are as follows: The remaining wind-gathering structure and electrical system parameters are the same as in Example 1.

[0037] The difference from Example 1 is that the four independent generator sets are replaced with one high-power generator covering the entire 42m height, and one inverter is used for centralized control.

[0038] Comparative analysis: A single-unit solution cannot independently track wind speed differences at different altitudes using MPPT. The bottom and top working points are coupled together, resulting in an overall efficiency that is about 10% to 20% lower than that of a layered solution. With centralized control of a single inverter, any generator failure will affect the MPPT strategy of the entire system. A single unit failure can cause the entire tower to shut down, resulting in low system availability. The installation and maintenance of high-power generators (hundreds of kilowatts) require large cranes, resulting in high operation and maintenance costs.

[0039] The difference from Example 1 is that the generator sets on each floor are connected in series and share one inverter, and the circuit breakers on each floor are normally closed.

[0040] Comparative analysis: The generators on each floor are connected in series. A fault on any floor (such as a short circuit) may cause the entire tower to shut down. Even if the inverter on that floor is disconnected, the series fault cannot be isolated. Using a single inverter makes it impossible to achieve independent MPPT tracking for each floor. The operating points of all floors must be optimized uniformly, and it is impossible to make precise adjustments based on the actual wind speed of each floor. The power collection efficiency of the series connection scheme is lower than that of the parallel connection scheme.

[0041] The above two sets of comparative examples fully demonstrate that the hierarchical independent power generation architecture combined with independent MPPT control and grid connection at each level is the most efficient, reliable, and flexible technical solution.

Claims

1. An integrated system of a hexagonal wind concentrator and a vertical axis generator, characterized in that, include: The outer support structure is arranged in a regular hexagonal shape, including 6 outer main columns distributed along the vertices of the regular hexagon (1). The internal support structure includes 6 inner auxiliary columns (2), which are evenly distributed along the inner distribution circle with the center of the outer main column (1) as the center; Six wind-gathering plates (3) are arranged in a radial direction, extending from an outer main column (1) to the corresponding inner auxiliary column (2), forming six radial wind-gathering channels. The layered independent power generation architecture includes at least two layers of vertical axis wind turbine generator sets (6). The generator sets (6) are installed at different heights in the central area surrounded by the six radial wind gathering channels. Each layer of generator sets is connected to an inverter (21) that is independently configured in each layer. The combined grid connection device includes a combined device (22), a step-up transformer (23), and a grid connection interface (24). The output terminals of each layer inverter (21) are connected to the combined device (22). The electrical energy combined by the combined device (22) is stepped up by the step-up transformer (23) and then connected to the grid through the grid connection interface (24). Each layer has an independent MPPT control unit, including a wind speed sensor (26) and an MPPT controller (25) set on each layer. The wind speed sensor (26) of each layer collects the wind speed data of that layer in real time, and the MPPT controller (25) of each layer independently adjusts the operating point of the inverter (21) of that layer according to the data of the wind speed sensor (26) of that layer.

2. The integrated system according to claim 1, characterized in that, The generator set (6) has 3 to 6 layers, with each layer distributed along the height of the tower.

3. The integrated system according to claim 2, characterized in that, The generator set (6) has 4 floors.

4. The integrated system according to claim 1, characterized in that, The number of wind speed sensors (26) in each layer is at least one per layer. The MPPT controller (25) of each layer independently executes the maximum power point tracking algorithm and independently optimizes the operating point of the inverter (21) according to the actual wind speed of the layer.

5. The integrated system according to claim 1, characterized in that, The output end of the combiner device (22) is connected in sequence to the step-up transformer (23) and the grid connection interface (24). The grid connection interface (24) is equipped with a main circuit breaker (29) and a surge protector (30).

6. The integrated system according to claim 1, characterized in that, It also includes a SCADA monitoring unit (27), which collects the tower's operating data and uploads the data to a remote monitoring terminal (33) via a communication module (32).

7. The integrated system according to claim 1, characterized in that, Interlayer cables (28) between each layer are routed along the interior of the inner auxiliary column (2).

8. The integrated system according to claim 1, characterized in that, It also includes an energy storage device (31), which is connected to the DC bus or AC bus of the combiner device (22).

9. A control method for an integrated system according to any one of claims 1 to 8, characterized in that, Includes the following steps: (a) Wind speed data acquisition at each floor: Wind speed sensors (26) at each floor collect wind speed data at the height of the floor in real time; (b) Independent MPPT for each layer: The MPPT controller (25) of each layer independently adjusts the operating point of the inverter (21) of the layer according to the wind speed data collected by the wind speed sensor (26) of the layer, so that the power generation system of the layer always operates at the maximum power point; (c) Combining and grid connection: The AC power output by each inverter (21) is transmitted to the combining device (22) through the circuit breaker (34) of each layer for centralized combination. The combined power is stepped up by the step-up transformer (23) and then connected to the grid through the grid connection interface (24). (d) Fault isolation: When a fault is detected in any layer, the inverter (21) of that layer is automatically disconnected, and the power generation systems of the remaining layers continue to operate normally.

10. The control method according to claim 9, characterized in that, The fault isolation in step (d) also includes an over-wind speed protection step: when the wind speed of any layer exceeds the rated wind speed of that layer, that layer independently performs braking or pitch control to reduce the rotation speed of that layer, while the other layers operate normally.

11. The control method according to claim 9, characterized in that, It also includes remote monitoring steps: the SCADA monitoring unit (27) collects the operating parameters of each floor of the tower in real time, including wind speed, power generation, inverter status and fault information of each floor, and uploads the data to the remote monitoring terminal (33) through the communication module (32) to realize remote monitoring and operation and maintenance management.

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