A starting and stopping method for a multi-impeller wind power system

Abstract

The present invention discloses a start-up and shutdown method applicable to a multi-impeller wind power system. The multi-impeller wind power system is a system that realizes the conversion of wind energy into electrical energy by installing multiple rows of wind power generating units in the same support structure. The wind power generating units are divided into multiple groups. When the system starts up or shuts down, all groups sequentially complete the start-up or shutdown actions according to the instructions of the control device. When the safety device issues an instruction and the system enters an uncontrolled shutdown, the wind power generating units can maintain the operating power generation state for a period of time by using a load unloading circuit, achieving the effect of delayed shutdown. This method of sequential start-up and shutdown can reduce the design load of the multi-impeller system and effectively control the system cost.

Description

Technical Field

[0001] The invention belongs to the technical field of wind power generation, and relates to a starting and stopping method applied to a multi-impeller wind power generation system. Background Art

[0002] With the continuous development of modern wind energy technology, the large-scale unit (i.e., the increase in the capacity of a single unit) is the most effective way to solve the problem of unit development costs, and the continuous development of offshore wind power projects has made the large-scale unit an inevitable development trend. With the increase in the capacity of the unit, the challenges encountered in the upgrade of traditional single-impeller wind turbines are becoming more and more severe. The sharp increase in load, the extra-long and extra-heavy blades and the extra-large torque have brought many difficulties to the design, production and installation of various components in the unit (such as variable pitch actuators, support structures, etc.).

[0003] A multi-blade wind power generation system is a system that installs multiple rows of wind power generation units in the same supporting structure to achieve wind energy to electrical energy conversion. Compared with traditional single-blade wind turbines, multi-blade wind power generation systems do not need to use extra-long and extra-heavy blades, and also avoid the appearance of excessive torque in the transmission system, providing another feasible way to scale up offshore wind turbines and reduce the development cost of the units.

[0004] The multi-impeller wind power generation system has the characteristics of parallel power generation of multiple wind power generation units. If the start-up or shutdown scheme is consistent with the single-impeller unit, that is, all impeller units are started or shut down at the same time, it may cause the problem of excessive design load, increase the cost of components such as supporting structures and foundations, and thus reduce the economic advantages of the multi-impeller wind power generation system. Therefore, it is necessary to develop a set of start-up and shutdown schemes suitable for the characteristics of multi-impeller wind power generation systems.

[0005] CN 205533018 U, CN 107407259 A, CN 102322399 A, CN 102305186 A, CN102269113 A, CN 102269111 A, CN 102305171 A, CN 102305172 A and CN 102305185 A all propose a form of a multi-blade wind turbine generator. CN 210049986 U proposes a multi-blade structure to achieve multi-stage wind energy utilization. CN 108368821 A, CN 110691905 A, CN 109219701 A and CN 107429661 A all propose a wind power station including a plurality of wind turbine systems arranged in rows and columns. None of these inventions describe the start-up and shutdown methods of the multi-blade wind power generation system. Summary of the invention

[0006] Aiming at the problem of large loads brought by traditional solutions during the startup and shutdown of multi-impeller wind power systems, the present invention provides a startup and shutdown method.

[0007] A technical solution for a startup and shutdown method applicable to multi-impeller wind power systems is as follows:

[0008] The wind power units of the multi-impeller wind power system are divided into multiple groups, and each group can contain one or more wind power units. When the system starts up or shuts down, all groups complete the startup or shutdown actions in sequence.

[0009] After the control device activates the startup or shutdown instruction, starting from the second group, the trigger condition for the startup or shutdown of the wind power unit is that the wind power unit in a group with a higher order has entered the startup or shutdown process, and the pitch angle or the impeller speed has reached a certain threshold. If it is the wind power unit in the first group, it directly enters the startup or shutdown process. When the system starts up, if one or more wind power units in any group cannot start due to special reasons (such as failures), the subsequent groups can skip the judgment of the status of these wind power units and directly enter the startup process. When the control device issues a shutdown instruction, if one or more wind power units in any group are already in the shutdown state due to special reasons (such as failures), the subsequent groups can skip the judgment of the status of these wind power units and directly enter the shutdown process.

[0010] The wind power unit is provided with a unloading circuit. After the safety device activates the system shutdown instruction, the wind power unit can maintain the operating state for a period of time after being out of control of the control device. After the shutdown condition of the group where it is located is met, the wind power unit enters the shutdown process.

[0011] The beneficial effects of the present invention are as follows: The present invention provides a feasible method for the startup and shutdown of multi-impeller wind power systems. This method can effectively reduce the loads during the startup and shutdown of the system, reduce the costs of components such as the support structure, and ensure the economy of the system. Description of the Drawings

[0012] Now, specific implementation examples will be described by way of example with reference to the drawings, where:

[0013] Figure 1 is the startup or shutdown flowchart of the multi-impeller system under the control device instruction;

[0014] Figure 2 is the shutdown flowchart of the multi-impeller system under the safety device instruction.

[0015] In the figure, 1 - control device instruction, 2 - wind power generation unit group judgment, 3 - execute start or stop instruction, 4 - wind power generation unit status judgment, 5 - global wind power generation unit status judgment, 6 - instruction execution end, 7 - safety device instruction, 8 - unloading circuit. Detailed implementation mode

[0016] The accompanying drawings are used to illustrate the features of the present invention and are not intended to show any actual structure or reflect details such as the dimensions and relative proportions of various components. To more clearly show the principle of the present invention and to avoid obscuring the principle of the present invention with unnecessary details, the examples in each figure have been simplified. These illustrations will not cause inconvenience to those skilled in the relevant field (wind power generation) in understanding the present invention.

[0017] The specific implementation scheme adopted by the present invention is:

[0018] The wind power generation units of the multi-impeller wind power generation system are divided into multiple groups, and each group can contain one or more wind power generation units. When the system starts or stops, all groups complete the start or stop actions in sequence.

[0019] As Figure 1 shown in the flowchart, when the multi-impeller wind power generation system is running normally, the control device issues an instruction (1) for system start or stop, and then judges the group of the wind power generation unit (2). If the wind power generation unit belongs to the first group, the start or stop instruction (3) is directly executed. If the wind power generation unit does not belong to the first group, the local wind power generation unit status judgment (4) is executed to judge whether the wind power generation units in a group in front have entered the start or stop process and whether the pitch angle or the impeller speed has reached a certain threshold. If all conditions are met, the start or stop instruction (3) is executed, otherwise the original state remains unchanged.

[0020] When the system starts, if one or more wind power generation units in any group cannot start due to special reasons (such as a fault), the subsequent groups can skip the local wind power generation unit status judgment (4) and directly execute the start instruction (3). When a stop instruction (1) is issued by the control device, if one or more wind power generation units in any group are in a stopped state due to special reasons (such as a fault), the subsequent groups can skip the local wind power generation unit status judgment (4) and directly execute the stop instruction (3).

[0021] As Figure 2In the flowchart shown, when the safety device activates the system shutdown command (7), the wind power generation unit uses the unloading circuit (8) to keep the wind power generation unit in operation for a period of time after it is no longer controlled by the control device, delaying the entry into the shutdown process (3). After the wind power generation unit status judgment (4) of the group is satisfied, the wind power generation unit enters the shutdown process (3).

Claims

1. A starting and stopping method for a multi-impeller wind power system, characterized in that, The wind power generation units of the multi-impeller wind power generation system are divided into multiple groups. Each group can contain one wind power generation unit or multiple wind power generation units. When the system starts up or shuts down, all groups complete the start-up or shutdown actions in sequence. After the control device activates the start-up or shutdown instruction, starting from the second group, the trigger condition for the start-up or shutdown of the wind power generation unit is that the wind power generation units in the group with a higher order in sequence have entered the start-up or shutdown process, and the pitch angle or the impeller speed has reached a certain threshold. If it is a wind power generation unit in the first group, it directly enters the start-up or shutdown process. When the system starts up, if one or more wind power generation units in any group cannot start due to a fault, the subsequent groups will skip the judgment of the status of these wind power generation units and directly enter the start-up process. When the system shuts down, if one or more wind power generation units in any group are in the shutdown state due to a fault, the subsequent groups will skip the judgment of the status of these wind power generation units and directly enter the shutdown process.

2. The starting and stopping method for a multi-impeller wind power system according to claim 1, characterized in that, The wind power generation unit is provided with a unloading circuit. When the safety device activates the system shutdown instruction, the wind power generation unit can maintain the operating power generation state for a period of time after being out of the control of the control device. After the shutdown condition of the group where it is located is met, the wind power generation unit enters the shutdown process.

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