Power grid outage anti-over-speed protection method and system based on centralized energy storage, and medium

Abstract

The application provides a power grid power failure anti-over-speed protection method and system based on centralized energy storage, and a medium, and belongs to the technical field of emergency control of wind turbine generators. The method comprises the following steps: calculating the yaw load of the current wind turbine generator; determining whether the current yaw actuator can meet the load demand according to the yaw load; in the case that the current yaw actuator can meet the load demand, calculating the required electric energy according to the yaw load and the power of the yaw actuator; controlling the centralized energy storage system to reserve the required electric energy; in the case that emergency yaw is needed and the power grid is powered off, controlling the centralized energy storage system to provide electric energy for the yaw actuator. The method calculates the yaw load of the current wind turbine generator to confirm that the current yaw actuator of the wind turbine generator can meet the load demand, and adopts the centralized energy storage system to reserve the required electric energy for the yaw actuator, so as to provide electric energy for the yaw actuator in the case that emergency yaw is needed and the power grid is powered off, and ensure the safety of the unit.

Description

Technical Field

[0001] This invention relates to the field of emergency control technology for wind turbine generator sets, specifically to a grid power failure overspeed protection method based on centralized energy storage, a grid power failure overspeed protection system based on centralized energy storage, and a machine-readable storage medium. Background Technology

[0002] During the shutdown process, the wind turbine blades are usually gradually feathered to 90 degrees, and the wind turbine shuts down safely. However, due to various reasons such as pitch system failure, blade jamming, sudden power outage, and inadequate routine maintenance, the wind turbine may fail to shut down, which may lead to overspeed or even runaway. If it is not controlled in time, it may cause serious production accidents such as blade breakage and tower collapse. In extreme cases, it may even cause personal injury accidents, resulting in significant economic losses and safety management responsibilities.

[0003] In recent years, many wind turbine units have introduced emergency yaw strategies that can adjust the angle between the wind turbine rotor and the wind direction. When the angle reaches more than 30 degrees, the wind energy absorbed by the wind turbine rotor will be effectively reduced. The emergency yaw "crosswind" strategy adds a last safety guarantee for the unit in emergency situations where normal shutdown fails, effectively improving the unit's safety performance and reducing the occurrence of serious accidents.

[0004] Given the current environment where the proportion of new energy sources is gradually increasing and changes in the structure of traditional power generation are leading to a decline in regional power grid stability, this should be a key consideration. To improve grid stability, many wind farms require the simultaneous installation of centralized energy storage devices during construction to stabilize grid performance.

[0005] Currently, when a wind turbine experiences a serious malfunction and cannot be shut down normally by retracting the propeller, emergency yaw for side-to-wind shutdown is the mainstream method commonly chosen for overall turbine safety control in the wind power industry, as it has the advantages of being simple and easy to operate. However, existing methods cannot perform yaw maneuvers in the event of a grid power outage, and they do not perform safety calculations for the loads required for yaw in overrunning conditions. This seriously affects the effectiveness and safety of the emergency yaw strategy. Summary of the Invention

[0006] The purpose of this invention is to provide a method, system, and medium for grid outage overspeed protection based on centralized energy storage. This method calculates the yaw load of the current wind turbine to confirm that the current yaw actuator of the wind turbine can meet the load requirements. At the same time, a centralized energy storage system is used to reserve the required power for the yaw actuator, so as to provide power to the yaw actuator in the event of emergency yaw and grid outage, thereby avoiding the failure of emergency yaw action and ensuring the safety of the unit.

[0007] To achieve the above objectives, a first aspect of the present invention provides a method for overspeed protection against power outages based on centralized energy storage, the method comprising:

[0008] Calculate the yaw load of the current wind turbine;

[0009] Determine whether the current yaw actuator can meet the load requirements based on the yaw load;

[0010] Given that the current yaw actuator can meet the load requirements, the required electrical energy is calculated based on the yaw load and the power of the yaw actuator.

[0011] Control the centralized energy storage system to reserve the required electrical energy;

[0012] In the event of an emergency yaw and a power grid outage, the centralized energy storage system provides power to the yaw actuator.

[0013] In this embodiment of the application, calculating the yaw load of the current wind turbine includes:

[0014] Define the first cut-out wind speed value of the wind turbine generator under the first preset time average wind speed and the second cut-out wind speed value of the wind turbine generator under the second preset time average wind speed.

[0015] Simulate the different operating states of a wind turbine generator set at the first cut-out wind speed value or the second cut-out wind speed value;

[0016] Simulation calculation of the vertical component torque of the yaw bearing under different operating conditions;

[0017] The maximum value of the vertical component moment obtained from the simulation is determined as the yaw load of the current wind turbine. Calculating the yaw load of the wind turbine through simulation provides a data foundation for assessing its emergency yaw response capability.

[0018] In this embodiment, the different operating states include at least: normal operating state and fault + yaw operating state. Of the two states, one is the normal state of the wind turbine and the other is the extreme state of the wind turbine. The yaw load obtained by simulating based on these two states is more helpful in judging the emergency yaw response capability of the wind turbine.

[0019] In this embodiment of the application, determining whether the current yaw actuator can meet the load requirements based on the yaw load includes:

[0020] The braking torque of the yaw brake during yaw is calculated based on the yaw brake design parameters of the wind turbine.

[0021] Compare the sum of the braking torque and the yaw load with the rated torque of the current yaw actuator;

[0022] If the rated torque is greater than the sum of the braking torque and the yaw load, then the current yaw actuator is determined to meet the load requirements; otherwise, the current yaw actuator is determined to be unable to meet the load requirements.

[0023] In this embodiment of the application, determining whether the current yaw actuator can meet the load requirements based on the yaw load includes:

[0024] The braking torque of the yaw brake during yaw is calculated based on the yaw brake design parameters of the wind turbine.

[0025] The sum of the braking torque and the yaw load is compared with the instantaneous maximum torque of the current yaw actuator;

[0026] If the instantaneous maximum torque is greater than the sum of the braking torque and the yaw load, then the current yaw actuator is determined to meet the load requirements; otherwise, the current yaw actuator is determined to be unable to meet the load requirements.

[0027] In this embodiment of the application, the calculation of the required electrical energy based on the yaw load and the power of the yaw actuator includes:

[0028] E=N*A*Pn*t / η

[0029] Where E is the total energy of one yaw of the yaw system; N is the number of yaw motors; A is the amplification factor; Pn is the rated power of the yaw motor; t is the time for one emergency yaw; and η is the efficiency of the motor.

[0030] In this embodiment of the application, the method further includes:

[0031] If it is determined that the current yaw actuator cannot meet the load requirements, replace the yaw actuator structure.

[0032] The required electrical energy is calculated based on the power of the new yaw actuator and the yaw load. Replacing the yaw actuator ensures that it meets emergency yaw requirements, guarantees unit safety, and saves costs.

[0033] A second aspect of the present invention provides a grid overspeed protection system based on centralized energy storage, the system comprising: a wind farm control system, a centralized energy storage system, a control switch, and a wind turbine generator;

[0034] The centralized energy storage system is connected to the wind turbine through a power collection line, which is connected to the power grid. The control switch is installed on the connection line between the power collection line, the power grid, and the centralized energy storage system. It is used to disconnect the energy transmission channel from the centralized energy storage system to the power grid in the event of emergency yaw and power grid failure, so that the centralized energy storage system can supply power to the yaw actuator of the wind turbine through the power collection line.

[0035] The wind farm control system is connected to the centralized energy storage system and the wind turbine. The control system is used to: calculate the yaw load of the current wind turbine; determine whether the current yaw actuator can meet the load requirements based on the yaw load; if the current yaw actuator can meet the load requirements, calculate the required electrical energy based on the yaw load and the power of the yaw actuator; and control the centralized energy storage system to reserve the required electrical energy to provide power to the wind turbine in the event of emergency yaw and grid failure. This system can calculate the yaw load of the current wind turbine to confirm that the current yaw actuator can meet the load requirements. Simultaneously, it controls the centralized energy storage system to reserve the required electrical energy for the yaw actuator, providing power to the yaw actuator in the event of emergency yaw and grid failure, thus preventing the failure of emergency yaw actions and ensuring turbine safety.

[0036] In this embodiment of the application, the centralized energy storage system includes: an energy storage unit, an energy storage unit management system, an energy storage converter, a step-up transformer, and a supervising energy management system;

[0037] The energy storage unit management system is connected to the energy storage unit and the energy storage converter. The energy storage converter is connected to the step-up transformer. The upper-level energy management system is connected to the energy storage unit management system, the energy storage converter, and the control switch. The upper-level energy management system is used to control the energy storage unit management system to reserve the required energy and to control the control switch to disconnect the channel for the centralized energy storage system to supply energy to the grid in the event of emergency yaw and grid power failure.

[0038] On the other hand, the present invention provides a machine-readable storage medium storing instructions for causing a machine to execute the aforementioned grid overspeed protection method based on centralized energy storage.

[0039] Through the above technical solutions, on the one hand, it is possible to calculate and simulate the yaw load of the unit, ensuring that the yaw actuator can meet the load requirements under emergency yaw conditions and avoid safety accidents caused by insufficient driving force of the yaw actuator; on the other hand, by taking advantage of the convenience of centralized energy storage systems, in emergency situations such as wind turbine overspeed when the power grid fails, the centralized energy storage system can be controlled to supply energy to complete the unit's emergency yaw deviating from the main wind direction, ensuring the safe shutdown of the unit.

[0040] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0041] The accompanying drawings are provided to further illustrate embodiments of the present invention and form part of the specification. They are used together with the following detailed description to explain the embodiments of the present invention, but do not constitute a limitation thereof. In the drawings:

[0042] Figure 1 This is a flowchart of a grid overspeed protection method based on centralized energy storage according to one embodiment of the present invention;

[0043] Figure 2 This is a block diagram of a grid overspeed protection system based on centralized energy storage provided in one embodiment of the present invention;

[0044] Figure 3 This is a schematic diagram of a grid overspeed protection system based on centralized energy storage provided in one embodiment of the present invention. Detailed Implementation

[0045] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0046] Figure 1 This is a flowchart of a grid overspeed protection method based on centralized energy storage according to one embodiment of the present invention. Figure 1 As shown, the method includes:

[0047] S1: Calculate the yaw load of the current wind turbine. According to the principle of mechanical transmission, the key parameter for the yaw motor driving force acting on the yaw bearing is the vertical component torque M of the yaw bearing. ZT .

[0048] In this embodiment of the application, calculating the yaw load of the current wind turbine includes:

[0049] Define a first cut-out wind speed value for the wind turbine generator under a first preset time average wind speed and a second cut-out wind speed value for the wind turbine generator under a second preset time average wind speed. In one embodiment, the first preset time is 10 minutes and the second preset time is 3 seconds.

[0050] Simulate the different operating states of a wind turbine generator set at the first cut-out wind speed value or the second cut-out wind speed value.

[0051] The vertical component torque of the yaw bearing under different operating conditions was simulated and calculated.

[0052] The maximum value of the vertical component moment obtained from the simulation is determined as the yaw load of the current wind turbine. Calculating the yaw load of the wind turbine through simulation provides a data foundation for assessing its emergency yaw response capability.

[0053] In this embodiment, the different operating states include at least: normal operating state and fault + yaw operating state. Of the two states, one is the normal state of the wind turbine and the other is the extreme state of the wind turbine. The yaw load obtained by simulating based on these two states is more helpful in judging the emergency yaw response capability of the wind turbine.

[0054] S2: Determine whether the current yaw actuator can meet the load requirements based on the yaw load.

[0055] In one embodiment, determining whether the current yaw actuator can meet the load requirements based on the yaw load includes:

[0056] The braking torque T of the yaw brake during yaw is calculated based on the yaw brake design parameters of the wind turbine. B ;

[0057] The braking torque T B With yaw load M MAX The sum of these and the rated torque T of the current yaw actuator N In comparison, the rated torque of the yaw actuator is calculated based on the rated capacity of the yaw motor.

[0058] If the rated torque T N Greater than the braking torque T B With yaw load M MAX If the sum of the values ​​is equal to the sum of the values ​​...

[0059] In other embodiments, determining whether the current yaw actuator can meet the load requirements based on the yaw load includes:

[0060] The braking torque T of the yaw brake during yaw is calculated based on the yaw brake design parameters of the wind turbine. B ;

[0061] The braking torque T B With yaw load M MAX The sum of these and the instantaneous maximum torque T of the current yaw actuator MAX Compare;

[0062] If the instantaneous maximum torque T MAX Greater than the braking torque T B With yaw load M MAX If the sum of the values ​​is equal to the sum of the values ​​...

[0063] S3: If the current yaw actuator can meet the load requirements, calculate the required electrical energy based on the yaw load and the power of the yaw actuator.

[0064] If the current yaw actuator cannot meet the load requirements, replace the yaw actuator structure.

[0065] The required electrical energy is calculated based on the power of the new yaw actuator and the yaw load. Replacing the yaw actuator ensures that it meets emergency yaw requirements, guarantees unit safety, and saves costs.

[0066] S4: Control the centralized energy storage system to reserve the required electrical energy. In one embodiment, to ensure the safe emergency yaw of the wind turbine, the reserved electrical energy is recommended to be the amount of electrical energy required for a single wind turbine at T. MAX It requires five times the energy needed to yaw 0-90° under certain conditions.

[0067] S5: In the event of an emergency yaw and a power grid outage, control the centralized energy storage system to provide power to the yaw actuator.

[0068] In this embodiment of the application, the calculation of the required electrical energy based on the yaw load and the power of the yaw actuator includes:

[0069] E=N*A*Pn*t / η

[0070] Where E is the total energy of the yaw system for one yaw; N is the number of yaw motors; A is the amplification factor, which is used to evaluate its transient overload energy and can be set based on experience; Pn is the rated power of the yaw motor; t is the time for one emergency yaw, i.e. the time taken for yaw from 0 to 90°; and η is the efficiency of the motor, which is generally taken as 0.7-0.85.

[0071] A second aspect of this invention provides a grid overspeed protection system based on centralized energy storage, such as... Figure 2 As shown, the system includes: a wind farm control system, a centralized energy storage system, control switches, and wind turbine generators;

[0072] The centralized energy storage system is connected to the wind turbine through a power collection line, which is connected to the power grid. The control switch is installed on the connection line between the power collection line, the power grid, and the centralized energy storage system. It is used to disconnect the energy transmission channel from the centralized energy storage system to the power grid in the event of emergency yaw and power grid failure, so that the centralized energy storage system can supply power to the yaw actuator of the wind turbine through the power collection line.

[0073] The wind farm control system is connected to the centralized energy storage system and the wind turbine. The control system is used to: calculate the yaw load of the current wind turbine; determine whether the current yaw actuator can meet the load requirements based on the yaw load; if the current yaw actuator can meet the load requirements, calculate the required electrical energy based on the yaw load and the power of the yaw actuator; and control the centralized energy storage system to reserve the required electrical energy to provide power to the wind turbine in the event of emergency yaw and grid failure. This system can calculate the yaw load of the current wind turbine to confirm that the current yaw actuator can meet the load requirements. Simultaneously, it controls the centralized energy storage system to reserve the required electrical energy for the yaw actuator, providing power to the yaw actuator in the event of emergency yaw and grid failure, thus preventing the failure of emergency yaw actions and ensuring turbine safety.

[0074] In the embodiments of this application, such as Figure 3 As shown, the centralized energy storage system includes: an energy storage unit, an energy storage unit management system, an energy storage converter, a step-up transformer, and a higher-level energy management system. The energy storage unit management system is connected to the energy storage unit and the energy storage converter. The energy storage converter is connected to the step-up transformer. The higher-level energy management system is connected to the energy storage unit management system, the energy storage converter, and a control switch. The higher-level energy management system is used to control the energy storage unit management system to reserve the required energy and to control the control switch to disconnect the energy transmission channel from the centralized energy storage system to the grid in the event of emergency yaw and grid power failure.

[0075] In an emergency, if a wind turbine fails to retract its propeller and shut down, and the power grid experiences a power outage, the turbine will lack yaw power and cannot complete an emergency yaw shutdown. When the wind farm control system detects a turbine malfunction and its inability to retract its propeller while the power grid is abnormal, it will disconnect the first control switch via communication control to suspend energy supply to the grid, close the second control switch, and control the upper-level energy management system to request the energy storage system to convert and transmit electrical energy to the collector line. At this point, the turbine will trigger a normal emergency yaw shutdown.

[0076] In this embodiment, a unit PLC controller is installed on the wind turbine, and the wind farm control system communicates with the unit PLC controller. The energy storage unit can be a super battery or an energy storage system (ESS).

[0077] On the other hand, the present invention provides a machine-readable storage medium storing instructions for causing a machine to execute the aforementioned grid overspeed protection method based on centralized energy storage.

[0078] Those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware. This program is stored in a storage medium and includes several instructions to cause a microcontroller, chip, or processor to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0079] The optional embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details described above. Within the scope of the technical concept of the embodiments of the present invention, various simple modifications can be made to the technical solutions of the embodiments of the present invention, and these simple modifications all fall within the protection scope of the embodiments of the present invention. It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the embodiments of the present invention will not further describe the various possible combinations.

[0080] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the embodiments of the present invention, they should also be regarded as the content disclosed by the embodiments of the present invention.

Claims

1. A method for overspeed protection against power outages based on centralized energy storage, characterized in that, The method includes: Calculate the yaw load of the current wind turbine; Determine whether the current yaw actuator can meet the load requirements based on the yaw load; Given that the current yaw actuator can meet the load requirements, the required electrical energy is calculated based on the yaw load and the power of the yaw actuator. Control the centralized energy storage system to reserve the required electrical energy; In the event of an emergency yaw and a power grid outage, the centralized energy storage system is controlled to provide power to the yaw actuator. The calculation of the yaw load of the current wind turbine includes: Define the first cut-out wind speed value of the wind turbine generator under the first preset time average wind speed and the second cut-out wind speed value of the wind turbine generator under the second preset time average wind speed. Simulate the different operating states of a wind turbine generator set at the first cut-out wind speed value or the second cut-out wind speed value; Simulation calculation of the vertical component torque of the yaw bearing under different operating conditions; The maximum value of the vertical component moment obtained from the simulation is determined as the yaw load of the current wind turbine. The step of determining whether the current yaw actuator can meet the load requirements based on the yaw load includes: The braking torque of the yaw brake during yaw is calculated based on the yaw brake design parameters of the wind turbine. Compare the sum of the braking torque and the yaw load with the rated torque of the current yaw actuator; If the rated torque is greater than the sum of the braking torque and the yaw load, then the current yaw actuator is determined to meet the load requirements; otherwise, the current yaw actuator is determined to be unable to meet the load requirements.

2. The method for overspeed protection against power outages based on centralized energy storage according to claim 1, characterized in that, The different operating states include at least: normal operating state and fault + yaw operating state.

3. The method for overspeed protection against power outages based on centralized energy storage according to claim 1, characterized in that, Determining whether the current yaw actuator can meet the load requirements based on the yaw load includes: The braking torque of the yaw brake during yaw is calculated based on the yaw brake design parameters of the wind turbine. The sum of the braking torque and the yaw load is compared with the instantaneous maximum torque of the current yaw actuator; If the instantaneous maximum torque is greater than the sum of the braking torque and the yaw load, then it is determined that the current yaw actuator can meet the load requirements; otherwise, it is determined that the current yaw actuator cannot meet the load requirements.

4. The method for overspeed protection against power outages based on centralized energy storage according to claim 1, characterized in that, The required electrical energy is calculated based on the yaw load and the power of the yaw actuator, including: Where E is the total energy of one yaw of the yaw system; N is the number of yaw motors; A is the amplification factor; Pn is the rated power of the yaw motor; t is the time for one emergency yaw; and η is the efficiency of the motor.

5. The method for overspeed protection against power outages based on centralized energy storage according to claim 1, characterized in that, The method further includes: If it is determined that the current yaw actuator cannot meet the load requirements, replace the yaw actuator structure. The required electrical energy is calculated based on the power of the new yaw actuator and the yaw load.

6. A grid overspeed protection system based on centralized energy storage, characterized in that, The system includes: a wind farm control system, a centralized energy storage system, control switches, and wind turbine generators; The centralized energy storage system is connected to the wind turbine through a power collection line, which is connected to the power grid. The control switch is located on the connection line between the power collection line, the power grid, and the centralized energy storage system, and is connected to the centralized energy storage system. It is used to disconnect the energy transmission channel from the centralized energy storage system to the power grid in the event of an emergency yaw and a power outage. The wind farm control system is connected to the centralized energy storage system and the wind turbine. The wind farm control system is used to: calculate the yaw load of the current wind turbine; determine whether the current yaw actuator can meet the load requirements based on the yaw load; if the current yaw actuator can meet the load requirements, calculate the required electrical energy based on the yaw load and the power of the yaw actuator; control the centralized energy storage system to reserve the required electrical energy; and provide electrical energy to the wind turbine in the event of emergency yaw and grid power failure. The calculation of the yaw load of the current wind turbine includes: Define the first cut-out wind speed value of the wind turbine generator under the first preset time average wind speed and the second cut-out wind speed value of the wind turbine generator under the second preset time average wind speed. Simulate the different operating states of a wind turbine generator set at the first cut-out wind speed value or the second cut-out wind speed value; Simulation calculation of the vertical component torque of the yaw bearing under different operating conditions; The maximum value of the vertical component moment obtained from the simulation is determined as the yaw load of the current wind turbine. The step of determining whether the current yaw actuator can meet the load requirements based on the yaw load includes: The braking torque of the yaw brake during yaw is calculated based on the yaw brake design parameters of the wind turbine. Compare the sum of the braking torque and the yaw load with the rated torque of the current yaw actuator; If the rated torque is greater than the sum of the braking torque and the yaw load, then the current yaw actuator is determined to meet the load requirements; otherwise, the current yaw actuator is determined to be unable to meet the load requirements.

7. The grid overspeed protection system based on centralized energy storage according to claim 6, characterized in that, The centralized energy storage system includes: an energy storage unit, an energy storage unit management system, an energy storage converter, a step-up transformer, and a supervising energy management system; The energy storage unit management system is connected to the energy storage unit and the energy storage converter. The energy storage converter is connected to the step-up transformer. The upper-level energy management system is connected to the energy storage unit management system, the energy storage converter, and the control switch. The upper-level energy management system is used to control the energy storage unit management system to reserve the required energy and to control the control switch to disconnect the channel for the centralized energy storage system to supply energy to the grid in the event of emergency yaw and grid power failure.

8. A machine-readable storage medium, characterized in that, The machine-readable storage medium stores instructions for causing the machine to execute the grid overspeed protection method based on centralized energy storage as described in any one of claims 1-5 of this application.

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