A power control method and system based on a wind turbine generator transformer

Abstract

The application discloses a power control method and system based on a wind turbine generator transformer, and the method comprises the following steps: monitoring the running state of a heat dissipation system of the transformer in real time; if the running state is normal, the power is not limited; if the running state is abnormal, the abnormal mode of the heat dissipation system is judged, wherein the abnormal mode of the heat dissipation system comprises an oil pump fault mode, a fan fault mode and an oil pump and fan simultaneous fault mode; if the oil pump fault mode or the fan fault mode is judged, corresponding power limitation calculation is performed, so as to control the wind turbine generator to run in a power-limited mode; if the oil pump and fan simultaneous fault mode is judged, the wind turbine generator is stopped; the application can control the power of the wind turbine generator according to the winding temperature when the transformer heat dissipation system is detected to be abnormal, so as to ensure that the power generation of the wind turbine generator can be increased under the condition that the transformer is protected from over-temperature.

Description

Technical Field

[0001] This invention relates to the technical field of wind turbine power control, and in particular to a power control method and system based on a wind turbine transformer. Background Technology

[0002] Currently, offshore wind turbines have a capacity of over 10MW. Due to the advantages of oil-immersed transformers, such as small size and strong overload capacity, oil-immersed transformers are now widely used in wind turbines.

[0003] There are two main methods for cooling oil-immersed transformers in offshore wind turbines: forced oil circulation with forced water cooling or forced oil circulation with forced air cooling. When the transformer cooling system malfunctions, the wind turbine will typically shut down to prevent the transformer windings from overheating and damaging the transformer. If strong winds occur at this time, operation and maintenance personnel may be unable to go to sea to handle the transformer fault, resulting in significant power loss from the wind turbine. Therefore, in the event of a transformer radiator failure, it is crucial to be able to adjust the wind turbine's power output while ensuring that the transformer winding temperature remains within a safe range. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and propose a power control method and system based on a wind turbine transformer. By detecting the operating status of the transformer's heat dissipation system and evaluating the temperature at the highest point of the transformer winding, the power generation of the wind turbine can be adjusted.

[0005] The objective of this invention is achieved through the following technical solution: a power control method based on a wind turbine transformer, comprising the following steps:

[0006] S1. Monitor the operating status of the transformer's heat dissipation system in real time. If the operating status is normal, do not limit the power. If the operating status is abnormal, proceed to step S2.

[0007] S2. Determine the abnormal mode of the heat dissipation system, which includes oil pump failure mode, fan failure mode and simultaneous oil pump and fan failure mode.

[0008] S3. If the fault is determined to be either an oil pump failure mode or a fan failure mode, the corresponding power limit calculation is performed to control the wind turbine to operate at limited power. If the fault is determined to be both an oil pump failure mode and a fan failure mode, the wind turbine is shut down.

[0009] Furthermore, step S1 includes:

[0010] The wind turbine control system monitors the operating status of the transformer's heat dissipation system in real time. The operating status includes the operating status of the motor protection switch and contactor of the oil pump motor, the operating status of the motor protection switch and contactor of the external radiator cooling fan motor. If the operating status is normal, the power is not limited. If the operating status is abnormal, the process proceeds to step S2.

[0011] Furthermore, step S2 includes:

[0012] The wind turbine control system determines the abnormal mode of the cooling system, which includes oil pump failure mode, fan failure mode, and simultaneous failure mode of oil pump and fan.

[0013] If the motor protection switch and contactor of the oil pump motor are not in normal operating condition, the system will enter the oil pump fault mode; if the motor protection switch and contactor of the external radiator cooling fan motor are not in normal operating condition, the system will enter the fan fault mode; if both the motor protection switch and contactor of the oil pump motor and the motor protection switch and contactor of the external radiator cooling fan motor are not in normal operating condition, the system will enter the oil pump and fan fault mode simultaneously.

[0014] Furthermore, step S3 includes:

[0015] If the system determines that the oil pump has entered a fault mode, perform the following operations:

[0016] Assess the hot spot temperature of the transformer windings before the oil pump failure, and the hot spot temperature of the transformer windings 30 seconds before the failure. Fiber optic sensors are pre-installed on the transformer windings to measure the highest winding temperature Tr. Power limiting is applied based on the hot spot temperature of the windings using a pre-set power level table and the corresponding load factor. Where:

[0017] When the winding hot spot temperature Tr is greater than t2, the wind turbine is shut down.

[0018] When the winding hot spot temperature Tr is between t1 and t2, the wind turbine uses a preset load factor of 1 for power limitation.

[0019] Furthermore, step S3 includes:

[0020] If the system determines that it has entered fan failure mode, perform the following operations:

[0021] Assess the hot spot temperature of the transformer windings before the fan failure, and the hot spot temperature of the transformer windings 30 seconds before the failure. Pre-install fiber optic sensors on the transformer windings to measure the highest winding temperature Tr. Based on the hot spot temperature of the windings, apply power limiting using the load factor corresponding to a pre-set power level table.

[0022] When the winding hot spot temperature Tr is less than t3, the wind turbine uses a preset load factor of 2 for power limitation.

[0023] When the winding hot spot temperature Tr is between t3 and t4, the wind turbine uses a preset load factor of 3 for power limitation.

[0024] When the winding hot spot temperature Tr is t4<Tr≤t5, the wind turbine uses a preset load factor of 4 for power limitation.

[0025] When the winding hot spot temperature Tr is greater than t5, the wind turbine will shut down.

[0026] Furthermore, the power level table is generated by conducting a temperature rise test on the transformer and setting corresponding load factors for each time period of the temperature rise test. The load factor corresponding to each time period can make the hot spot temperature of the transformer winding fluctuate within a preset safe temperature range, thereby enabling power limitation through each load factor.

[0027] A power control system based on a wind turbine transformer, used to implement the aforementioned power control method based on a wind turbine transformer, includes:

[0028] The wind turbine control system includes a wind turbine power acquisition system, a fiber optic winding thermometer, a motor protection switch for the oil pump motor, a contactor for the oil pump motor, a motor protection switch for the cooling fan motor, and a contactor for the cooling fan motor. The wind turbine control system is communicatively connected to the wind turbine power acquisition system, the fiber optic winding thermometer, the motor protection switch for the oil pump motor, the contactor for the oil pump motor, the motor protection switch for the cooling fan motor, and the contactor for the cooling fan motor.

[0029] Furthermore, the optical fiber winding thermometer is installed inside the transformer of the wind turbine, and the transformer is an oil-immersed transformer.

[0030] A non-transitory computer-readable medium storing instructions that, when executed by a processor, perform the steps of the power control method based on a wind turbine transformer described above.

[0031] A computing device includes a processor and a memory for storing processor-executable programs, wherein when the processor executes the programs stored in the memory, it implements the above-described power control method based on a wind turbine transformer.

[0032] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0033] This invention enables wind turbines to calculate the transformer winding temperature by analyzing the operating status of the cooling system and the transformer oil temperature when an abnormality is detected in the transformer cooling system. The power of the wind turbine is then controlled based on the winding temperature, thereby ensuring that the wind turbine can increase its power generation while protecting the transformer from overheating when the cooling system fails, thus improving the economic efficiency of the wind turbine. Attached Figure Description

[0034] Figure 1 This is a flowchart of the power control method.

[0035] Figure 2 This is a graph showing the temperature variation of the transformer winding hotspots within a safe range.

[0036] Figure 3 This is a diagram of the power control system architecture. Detailed Implementation

[0037] The present invention will be further described below with reference to specific embodiments.

[0038] Example 1

[0039] See Figure 1 As shown, the power control method based on wind turbine transformers provided in this embodiment includes the following steps:

[0040] S1. The wind turbine control system monitors the operating status of the transformer's heat dissipation system in real time. The operating status includes the operating status of the oil pump motor's motor protection switch and contactor, the operating status of the external radiator cooling fan motor's motor protection switch and contactor. If the operating status is normal, the power is not limited. If the operating status is abnormal, proceed to step S2.

[0041] S2. The wind turbine control system determines the abnormal mode of the cooling system, which includes oil pump failure mode, fan failure mode, and simultaneous oil pump and fan failure mode. Specifically, if the motor protection switch and contactor of the oil pump motor are not in normal operating condition, the system is determined to enter the oil pump failure mode; if the motor protection switch and contactor of the external radiator cooling fan motor are not in normal operating condition, the system is determined to enter the fan failure mode; if the motor protection switch and contactor of both the oil pump motor and the external radiator cooling fan motor are not in normal operating condition, the system is determined to enter the simultaneous oil pump and fan failure mode.

[0042] S3. If the fault is determined to be either an oil pump failure mode or a fan failure mode, the corresponding power limit calculation is performed to control the wind turbine to operate at limited power. If the fault is determined to be both an oil pump failure mode and a fan failure mode, the wind turbine is shut down.

[0043] a. If it is determined that the oil pump has entered a fault mode, perform the following operations:

[0044] Assess the hot spot temperature of the transformer windings before the oil pump failure, and the hot spot temperature of the transformer windings 30 seconds before the failure. Fiber optic sensors are pre-installed on the transformer windings to measure the highest winding temperature Tr. Power limiting is applied based on the hot spot temperature of the windings using a pre-set power level table and the corresponding load factor. Where:

[0045] When the winding hot spot temperature Tr is greater than 90, the wind turbine will be shut down.

[0046] When the winding hot spot temperature Tr is 0 < Tr ≤ 90, the wind turbine uses a preset load factor of 1 for power limitation.

[0047] The power level table is shown in Table 1 below:

[0048]

[0049]

[0050] Table 1 Power Levels of Oil Pump Failure Modes

[0051] This power level table is designed to keep the hot spot temperature of the winding within a safe range. See the temperature curves below. Figure 2 As shown;

[0052] In the oil pump failure mode, if the transformer winding temperature reaches 90 degrees Celsius, the wind turbine will shut down.

[0053] b. If it is determined that the fan has entered a fault mode, perform the following operations:

[0054] Assess the hot spot temperature of the transformer windings before the fan failure, and the hot spot temperature of the transformer windings 30 seconds before the failure. Pre-install fiber optic sensors on the transformer windings to measure the highest winding temperature Tr. Based on the hot spot temperature of the windings, apply power limiting using the load factor corresponding to a pre-set power level table.

[0055] When the winding hot spot temperature Tr is less than 30°C, the wind turbine uses a preset load factor of 2 for power limitation.

[0056] When the winding hot spot temperature Tr is 30<Tr≤60, the wind turbine uses a preset load factor of 3 for power limitation.

[0057] When the winding hot spot temperature Tr is 60<Tr≤90, the wind turbine uses a preset load factor of 4 for power limitation.

[0058] When the winding hot spot temperature Tr is greater than 90, the wind turbine will be shut down.

[0059] The power level table is shown in Table 2 below:

[0060]

[0061] Table 2 Power Stages of Fan Failure Modes

[0062] Example 2

[0063] See Figure 3 As shown, this embodiment discloses a power control system based on a wind turbine transformer, used to implement the power control method based on a wind turbine transformer described in Embodiment 1, including:

[0064] The wind turbine control system 1, wind turbine power acquisition system 2, fiber optic winding thermometer 3, oil pump motor protection switch 4, oil pump motor contactor 5, cooling fan motor protection switch 6, and cooling fan motor contactor 7 are respectively connected in communication with the wind turbine power acquisition system 2, fiber optic winding thermometer 3, oil pump motor protection switch 4, oil pump motor contactor 5, cooling fan motor protection switch 6, and cooling fan motor contactor 7. The fiber optic winding thermometer 3 is installed inside the transformer 8 of the wind turbine, and the transformer 8 is an oil-immersed transformer.

[0065] Example 3

[0066] This embodiment discloses a non-transitory computer-readable medium storing instructions that, when executed by a processor, perform the steps of the power control method based on a wind turbine transformer as described in Embodiment 1.

[0067] In this embodiment, the non-transitory computer-readable medium can be a disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), USB flash drive, portable hard drive, etc.

[0068] Example 4

[0069] This embodiment discloses a computing device, including a processor and a memory for storing processor-executable programs. When the processor executes the program stored in the memory, it implements the power control method based on wind turbine transformers described in Embodiment 1.

[0070] The computing device described in this embodiment may be a desktop computer, laptop computer, smartphone, PDA handheld terminal, tablet computer, programmable logic controller (PLC), or other terminal device with processor function.

[0071] The above-described embodiments are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Therefore, any changes made in accordance with the shape and principle of the present invention should be covered within the protection scope of the present invention.

Claims

1. A power control method based on a wind turbine transformer, characterized in that, Includes the following steps: S1. Monitor the operating status of the transformer's heat dissipation system in real time. If the operating status is normal, do not limit the power. If the operating status is abnormal, proceed to step S2. S2. Determine the abnormal mode of the heat dissipation system, which includes oil pump failure mode, fan failure mode and simultaneous oil pump and fan failure mode. S3. If the fault is determined to be either an oil pump failure mode or a fan failure mode, the corresponding power limit calculation is performed to control the wind turbine to operate at limited power. If the fault is determined to be both an oil pump failure mode and a fan failure mode, the wind turbine is shut down. If the system determines that the oil pump has entered a fault mode, perform the following operations: Assess the hot spot temperature of the transformer windings before the oil pump failure, and the hot spot temperature of the transformer windings 30 seconds before the failure. Fiber optic sensors are pre-installed on the transformer windings to measure the highest winding temperature Tr. Power limiting is applied based on the hot spot temperature of the windings using a pre-set power level table and the corresponding load factor. Where: When the winding hot spot temperature Tr is greater than t2, the wind turbine is shut down. When the winding hot spot temperature Tr is t1<Tr≤t2, the wind turbine uses a preset load factor of 1 for power limitation. If the system determines that it has entered fan failure mode, perform the following operations: Assess the hot spot temperature of the transformer windings before the fan failure, and the hot spot temperature of the transformer windings 30 seconds before the failure. Pre-install fiber optic sensors on the transformer windings to measure the highest winding temperature Tr. Based on the hot spot temperature of the windings, apply power limiting using the load factor corresponding to a pre-set power level table. When the winding hot spot temperature Tr is less than t3, the wind turbine uses a preset load factor of 2 for power limitation. When the winding hot spot temperature Tr is between t3 and t4, the wind turbine uses a preset load factor of 3 for power limitation. When the winding hot spot temperature Tr is t4<Tr≤t5, the wind turbine uses a preset load factor of 4 for power limitation. When the winding hot spot temperature Tr is greater than t5, the wind turbine is shut down. The power level table is generated by conducting a temperature rise test on the transformer and setting corresponding load factors for each time period of the temperature rise test. The load factor corresponding to each time period can make the hot spot temperature of the transformer winding fluctuate within the preset safe temperature range, thereby enabling power limitation through each load factor.

2. The power control method based on a wind turbine transformer according to claim 1, characterized in that, Step S1 includes: The wind turbine control system monitors the operating status of the transformer's heat dissipation system in real time. The operating status includes the operating status of the motor protection switch and contactor of the oil pump motor, the operating status of the motor protection switch and contactor of the external radiator cooling fan motor. If the operating status is normal, the power is not limited. If the operating status is abnormal, the process proceeds to step S2.

3. The power control method based on a wind turbine transformer according to claim 2, characterized in that, Step S2 includes: The wind turbine control system determines the abnormal mode of the cooling system, which includes oil pump failure mode, fan failure mode, and simultaneous failure mode of oil pump and fan. If the motor protection switch and contactor of the oil pump motor are not in normal operating condition, the system will enter the oil pump fault mode; if the motor protection switch and contactor of the external radiator cooling fan motor are not in normal operating condition, the system will enter the fan fault mode; if both the motor protection switch and contactor of the oil pump motor and the motor protection switch and contactor of the external radiator cooling fan motor are not in normal operating condition, the system will enter the oil pump and fan fault mode simultaneously.

4. A power control system based on a wind turbine transformer, characterized in that, The power control method based on a wind turbine transformer as described in any one of claims 1-3 includes: The wind turbine control system includes a wind turbine power acquisition system, a fiber optic winding thermometer, a motor protection switch for the oil pump motor, a contactor for the oil pump motor, a motor protection switch for the cooling fan motor, and a contactor for the cooling fan motor. The wind turbine control system is communicatively connected to the wind turbine power acquisition system, the fiber optic winding thermometer, the motor protection switch for the oil pump motor, the contactor for the oil pump motor, the motor protection switch for the cooling fan motor, and the contactor for the cooling fan motor.

5. A power control system based on a wind turbine transformer according to claim 4, characterized in that: The fiber optic winding thermometer is installed inside the transformer of the wind turbine, and the transformer is an oil-immersed transformer.

6. A non-transitory computer-readable medium storing instructions, characterized in that, When the instruction is executed by the processor, the steps of the power control method based on the wind turbine transformer according to any one of claims 1-3 are performed.

7. A computing device, comprising a processor and a memory for storing a processor-executable program, characterized in that, When the processor executes the program stored in the memory, it implements the power control method based on the wind turbine transformer as described in any one of claims 1-3.

Images