Wind turbine generator power optimization control method and system

Abstract

The wind turbine generator power optimization control method comprises the steps of collecting operation data of a wind turbine generator; the rotating speed of the generator is compared with the cut-in rotating speed and the rated rotating speed, and the running state of the wind turbine generator is divided into a standby state, a maximum power tracking area and a constant power control area; in the maximum power tracking area, based on the rotating speed and power change relation of the previous control period and the current control period, a first torque instruction is generated through dynamic step length tentative logic; in the constant power control area, the power upper limit set value is adjusted to generate a second torque instruction based on comparison between the state parameters of the generator and the converter and the preset temperature boundary; when the vibration amplitude enters the early warning interval, avoiding adjustment is executed in combination with the rotating speed or the variable pitch rate of the generator to generate a third torque instruction; and taking the minimum value of the torque instruction meeting the boundary constraint as a final control instruction. Under the condition that a complex mathematical formula and an AI model are not used, the thermal capacity margin and the mechanical vibration margin of the unit are used for dynamically adjusting a power output target, and the potential power generation capacity of the excavator unit is guaranteed under the condition that safety is guaranteed.

Description

Technical Field

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

[0002] Existing wind turbine power control methods typically suffer from the following problems: Reliance on ideal mathematical models: Existing technologies mostly employ optimal torque control or PID pitch control, which depend on precise aerodynamic formulas. However, in actual operation, blade contamination and changes in air density can cause the calculated values ​​to deviate from reality, resulting in power loss.

[0003] Lack of real-time response to component physical conditions: Existing control strategies typically use generator temperature and tower vibration as trigger conditions for "fault shutdown" rather than as reference variables for "power regulation." That is, as long as no error is reported, the unit blindly pursues maximum power, which can easily lead to component overheating or accelerated fatigue.

[0004] AI models are difficult to interpret and require high computing power: The neural network control methods that have emerged in recent years require high-performance controllers and have uninterpretable logic, making them difficult to deploy widely in traditional industrial PLCs. Summary of the Invention

[0005] This invention provides a power optimization control method and system for wind turbine units to overcome the aforementioned deficiencies in the prior art. It enables dynamic adjustment of the power output target by utilizing the thermal capacity margin and mechanical vibration margin of the unit without using complex mathematical formulas and AI models, thereby tapping the potential power generation capacity of the unit while ensuring safety.

[0006] This invention provides a method for optimizing the power control of wind turbine generators, comprising: Step S1: Collect real-time operating data of the wind turbine; Step S2: Compare the collected generator speed with the preset cut-in speed and rated speed to divide the wind turbine's operating state into standby state, maximum power tracking zone and constant power control zone; Step S3: When it is determined that the maximum power tracking zone is in, the first torque command is generated by using dynamic step size probing logic based on the relationship between the speed change and power change between the previous control cycle and the current control cycle. Step S4: When it is determined that the constant power control zone is in place, the upper limit setting value of the power is dynamically adjusted based on the comparison results of the generator state parameters and converter state parameters with the preset temperature boundary to generate the second torque command; Step S5: Calculate the vibration amplitude based on the unit vibration parameters. When the vibration amplitude enters the warning range, perform avoidance adjustment in combination with the current generator speed or pitch rate to generate a third torque command. Step S6: Perform a comprehensive judgment on the first torque command, the second torque command, and the third torque command, and select the minimum value that satisfies all boundary constraints as the final control command.

[0007] According to the wind turbine power optimization control method provided by the present invention, in step S1, the operating data includes: Environmental parameters, including ambient temperature and wind speed; Generator status parameters, including generator speed and generator stator temperature; Converter status parameters, including converter IGBT temperature; The unit's vibration parameters include the vibration amplitude of the tower in the X-axis direction and the vibration amplitude of the tower in the Y-axis direction.

[0008] According to the wind turbine power optimization control method provided by the present invention, step S2 specifically includes: If the current generator speed is less than the cut-in speed, it is determined to be in standby mode and power optimization will not be performed. If the current generator speed is greater than or equal to the cut-in speed and less than the rated speed, it is determined to be in the maximum power tracking zone, and proceed to step S3; If the current generator speed reaches the rated speed, it is determined to be in the constant power control zone, and proceed to step S4.

[0009] According to the wind turbine power optimization control method provided by the present invention, in step S3, the dynamic step size trial logic includes a positive step size adjustment logic step: If the generator speed in the current cycle is greater than the generator speed in the previous cycle, and the generator power in the current cycle is greater than the generator power in the previous cycle, then the direction of torque increase is determined to be correct. A positive preset step size is added to the current electromagnetic torque command to generate the first torque command. Furthermore, in step S3, the dynamic step size probing logic also includes a reverse step size adjustment logic step: If the generator speed in the current cycle is less than the generator speed in the previous cycle, and the generator power in the current cycle is less than the generator power in the previous cycle, then it is determined that the torque is too large, causing the speed to drop. Based on the current electromagnetic torque command, a reverse backoff step is subtracted to generate the first torque command.

[0010] According to the wind turbine power optimization control method provided by the present invention, in step S3, the dynamic step size probing logic further includes a dead zone locking logic step: If the generator speed in the current cycle is greater than the generator speed in the previous cycle, but the generator power change in the current cycle is less than the preset dead zone threshold, then the power is determined to be close to the limit, and the current torque command is kept unchanged as the first torque command.

[0011] According to the wind turbine power optimization control method provided by the present invention, step S4 specifically includes: Read the generator stator temperature and converter IGBT temperature; If the generator stator temperature and the converter IGBT temperature are both lower than the preset safety warning temperature, and the ambient temperature is lower than the preset low temperature threshold, the power upper limit setting will be increased to 105% of the rated power, and a second torque command will be generated based on the adjusted power upper limit setting. If either the generator stator temperature or the converter IGBT temperature exceeds the safety warning temperature, or if the temperature rise rate is detected to be greater than the preset temperature rise slope threshold, the power upper limit setting will be adjusted back to 100% of the rated power, and a second torque command will be generated based on the adjusted power upper limit setting. If the generator stator temperature or converter IGBT temperature continues to rise and approaches the fault trip temperature, the power upper limit setting will be reduced to 80% of the rated power, and a second torque command will be generated based on the adjusted power upper limit setting.

[0012] According to the wind turbine power optimization control method provided by the present invention, in step S5, the calculation of vibration amplitude specifically involves: Based on the collected vibration amplitudes of the tower along the X-axis and Y-axis, the root mean square values ​​of the vibration accelerations in the front-back and left-right directions of the tower are calculated and used as the vibration amplitudes.

[0013] According to the wind turbine power optimization control method provided by the present invention, step S5 specifically includes: When the vibration amplitude enters the warning range, determine whether the current generator speed is within the preset tower resonance speed band; If the result is yes, a forced jump torque value is generated as the third torque command to drive the generator speed to cross the resonant speed band at the maximum allowable acceleration; If the result is negative, the pitch rate is checked. If the pitch rate is greater than a preset high-frequency threshold, a hold command to maintain the current torque is generated as the third torque command, and a command to reduce pitch sensitivity is sent to the pitch system at the same time.

[0014] According to the wind turbine power optimization control method provided by the present invention, step S6 specifically includes: Set the final torque command to be equal to the minimum value among the first torque command, the second torque command, and the third torque command; The final torque command is sent to the converter controller for execution, and the corresponding pitch angle command is sent to the pitch actuator.

[0015] The present invention also provides a wind turbine power optimization control system, comprising: The data acquisition module collects real-time operating data of the wind turbine. The state division module compares the collected generator speed with the preset cut-in speed and rated speed to divide the wind turbine's operating state into standby state, maximum power tracking zone, and constant power control zone. The instruction generation module, when determining that it is in the maximum power tracking zone, generates a first torque instruction based on the relationship between the speed and power changes in the previous and current control cycles using dynamic step-size probing logic; when determining that it is in the constant power control zone, it dynamically adjusts the upper power limit setting based on the comparison results between the generator state parameters, converter state parameters and the preset temperature boundary to generate a second torque instruction; it calculates the vibration amplitude based on the unit vibration parameters, and when the vibration amplitude enters the warning range, it performs avoidance adjustment in combination with the current generator speed or pitch rate to generate a third torque instruction; The command output module comprehensively judges the first torque command, the second torque command, and the third torque command, and selects the minimum value that satisfies all boundary constraints as the final control command.

[0016] The wind turbine power optimization control method and system provided by this invention adopts a trial method based on dynamic step size in the maximum power tracking region, and directly adjusts according to the measured change trend of speed and power. This makes the control strategy unaffected by the drift of blade aerodynamic parameters and the measurement error of environmental parameters, and can adaptively find the true maximum power point under the current operating conditions.

[0017] Furthermore, due to the introduction of a dynamic power limit adjustment mechanism based on temperature boundaries, in low-temperature and well-heated environments, the unit is allowed to briefly exceed its rated power (i.e., "over-generation") within the thermal safety boundary, significantly increasing the unit's annual power generation. In high-temperature or rapidly rising environments, proactive load reduction instead of direct shutdown protects component lifespan and ensures the unit's grid connection rate.

[0018] Furthermore, this invention incorporates the tower vibration amplitude into the control closed loop in real time. By actively adjusting the torque or pitch strategy, the unit can quickly cross the resonance zone or reduce the intensity of the excitation source when the vibration enters the warning range. This active avoidance mechanism effectively suppresses the accumulation of fatigue loads on the tower and blades, significantly reduces the number of shutdowns caused by excessive vibration, and extends the mechanical service life of the unit.

[0019] Furthermore, this invention does not require complex mathematical calculations, high-order matrix operations, or AI models. The overall control logic is entirely based on physical state feedback and logic threshold judgment, which is easy to implement in standard industrial PLCs. Moreover, the code logic is clear, fault diagnosis is easy, and it has high applicability and reliability in industrial settings.

[0020] Furthermore, through the minimum value synthesis judgment logic in step S6, the system processes the three torque commands from MPPT, thermal safety, and vibration safety in parallel, and always selects the most conservative (minimum) torque value as the final output. This design ensures that the unit operates within the intersection of all physical constraints at all times, that is, while pursuing power generation efficiency, the thermal and mechanical safety of the equipment is always given the highest priority. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0022] Figure 1 This is a flowchart illustrating the wind turbine power optimization control method provided by the present invention.

[0023] Figure 2 This is a schematic diagram of the wind turbine power optimization control system provided by the present invention.

[0024] Figure 3 This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0026] The following is combined Figures 1 to 3 This document describes embodiments of the wind turbine power optimization control method and system of the present invention. It should be understood that the following descriptions are merely illustrative embodiments of the present invention and do not constitute any specific limitation on the present invention.

[0027] like Figure 1 As shown, the present invention provides a power optimization control method for wind turbine generators, which includes the following steps: Step S1: Collect real-time operating data of the wind turbine; Step S2: Compare the collected generator speed with the preset cut-in speed and rated speed to divide the wind turbine's operating state into standby state, maximum power tracking zone and constant power control zone; Step S3: When it is determined that the maximum power tracking zone is in, the first torque command is generated by using dynamic step size probing logic based on the relationship between the speed change and power change between the previous control cycle and the current control cycle. Step S4: When it is determined that the constant power control zone is in place, the upper limit setting value of the power is dynamically adjusted based on the comparison results of the generator state parameters and converter state parameters with the preset temperature boundary to generate the second torque command; Step S5: Calculate the vibration amplitude based on the unit vibration parameters. When the vibration amplitude enters the warning range, perform avoidance adjustment in combination with the current generator speed or pitch rate to generate a third torque command. Step S6: Perform a comprehensive judgment on the first torque command, the second torque command, and the third torque command, and select the minimum value that satisfies all boundary constraints as the final control command.

[0028] As can be seen from the above embodiments, the wind turbine power optimization control method provided by the present invention adopts a trial method based on dynamic step size in the maximum power tracking region, and directly adjusts according to the measured change trend of speed and power, so that the control strategy is not affected by the drift of blade aerodynamic parameters and the measurement error of environmental parameters, and can adaptively find the true maximum power point under the current operating conditions.

[0029] Furthermore, due to the introduction of a dynamic power limit adjustment mechanism based on temperature boundaries, in low-temperature and well-heated environments, the unit is allowed to briefly exceed its rated power (i.e., "over-generation") within the thermal safety boundary, significantly increasing the unit's annual power generation. In high-temperature or rapidly rising environments, proactive load reduction instead of direct shutdown protects component lifespan and ensures the unit's grid connection rate.

[0030] Furthermore, this invention incorporates the tower vibration amplitude into the control closed loop in real time. By actively adjusting the torque or pitch strategy, the unit can quickly cross the resonance zone or reduce the intensity of the excitation source when the vibration enters the warning range. This active avoidance mechanism effectively suppresses the accumulation of fatigue loads on the tower and blades, significantly reduces the number of shutdowns caused by excessive vibration, and extends the mechanical service life of the unit.

[0031] Furthermore, this invention does not require complex mathematical calculations, high-order matrix operations, or AI models. The overall control logic is entirely based on physical state feedback and logic threshold judgment, which is easy to implement in standard industrial PLCs. Moreover, the code logic is clear, fault diagnosis is easy, and it has high applicability and reliability in industrial settings.

[0032] Furthermore, through the minimum value synthesis judgment logic in step S6, the system processes the three torque commands from MPPT, thermal safety, and vibration safety in parallel, and always selects the most conservative (minimum) torque value as the final output. This design ensures that the unit operates within the intersection of all physical constraints at all times, that is, while pursuing power generation efficiency, the thermal and mechanical safety of the equipment is always given the highest priority.

[0033] The above method will be described in detail below with reference to embodiments. It should be understood that the following description is merely an illustrative embodiment of the present invention and does not constitute any limitation on the present invention.

[0034] First, the wind turbine power optimization control method of the present invention begins with step S1, which involves real-time acquisition of wind turbine operating data. Specifically, the acquired operating data includes environmental parameters, generator status parameters, converter status parameters, and turbine vibration parameters. Further, in an optional embodiment, the environmental parameters include ambient temperature and wind speed; the generator status parameters include generator speed and generator stator temperature; the converter status parameters include converter IGBT temperature; and the turbine vibration parameters include the tower's X-axis vibration amplitude and tower's Y-axis vibration amplitude.

[0035] Specifically, the real-time generator speed can be measured using a photoelectric encoder or rotary transformer installed on the non-drive end of the generator, and the signal is transmitted to the main controller via a speed transmitter. The generator stator temperature can be acquired using PT100 platinum resistance thermometers embedded in the stator winding slots and ends; typically, the average or maximum temperature of the three-phase windings is taken as valid data. The converter power device temperature can be directly read from the NTC thermistor integrated within the converter IGBT module and uploaded to the main control PLC via converter communication protocols (such as CANopen or Profinet). The tower vibration amplitude can be acquired using dual-axis (X / Y axis) accelerometers installed on the nacelle base or tower top, and the vibration amplitude (usually the root mean square value, RMS) is obtained through integration. Other parameters, such as the current output power, can be acquired using voltage transformers (PTs) and current transformers (CTs) on the converter grid side to collect grid voltage and current, and the active power value can be calculated. Environmental parameters (ambient temperature and wind speed) can be acquired using an ultrasonic anemometer and temperature sensor installed on the wind vane bracket outside the nacelle.

[0036] Next, in step S2, the collected generator speed is compared with the preset cut-in speed and rated speed to divide the wind turbine's operating state into standby state, maximum power tracking zone, and constant power control zone. Specifically, if the current generator speed is less than the cut-in speed, it is determined to be in standby state and no power optimization is performed; if the current generator speed is greater than or equal to the cut-in speed but less than the rated speed, it is determined to be in the maximum power tracking zone and proceeds to step S3; if the current generator speed reaches the rated speed, it is determined to be in the constant power control zone and proceeds to step S4.

[0037] Specifically, in this step, firstly, two physical speed thresholds are preset in the controller: the cut-in speed threshold (the minimum physical speed at which the wind turbine starts generating electricity from the grid) and the rated speed threshold (the design speed at which the wind turbine reaches full power generation). The system reads the real-time generator speed once every control cycle (e.g., every 10ms) and performs the following cascaded judgment.

[0038] First, for standby state determination, the system checks if the current rotational speed is less than the cut-in speed threshold. If the result is "yes," it indicates that the current wind energy is insufficient to drive the unit to generate electricity effectively, or that the unit is in the startup acceleration phase and has not yet been connected to the grid. In this case, the system determines that the unit is in standby state. In this state, the system prohibits entering the dynamic step size probing logic in step S3, and also prohibits entering the heat capacity determination logic in step S4. The system only performs basic maintenance control, waiting for the rotational speed to increase.

[0039] Secondly, regarding the Maximum Power Tracking (MPPT) determination, if the engine speed does not meet the standby conditions, the system continues to determine whether the current engine speed is greater than or equal to the cut-in speed threshold and less than the rated speed threshold. If the result is "yes," it indicates that the unit is in a partial load operation phase, and the primary goal at this time is to capture as much wind energy as possible. The system determines that the unit is in the MPPT zone. At this point, the system automatically activates the dynamic step-size probing strategy in step S3, continuously fine-tuning the torque to find the maximum power point at the current wind speed. At this time, the logic in step S4 is either in a dormant state or only serves as background monitoring, and does not participate in active control.

[0040] Furthermore, regarding the determination of the constant power control zone, the system judges whether the current speed is close to or has reached the rated speed threshold (usually manifested as being greater than or equal to the rated speed threshold, or entering a small neighborhood of the rated speed). If the result is "yes," it means that the unit has reached or is close to full load, and continuing to increase the speed may lead to overspeed. At this time, the primary goal becomes limiting power and protecting the equipment. The system determines that the unit is in the constant power control zone. At this time, the system freezes the trial logic of step S3 (no longer blindly increasing torque) and activates step S4 instead. At this time, control is transferred to the logic based on the temperature boundary, and the thermal capacity margin determines whether to maintain the rated power, over-generation (105%), or implement load reduction.

[0041] Through the above steps, the two objectives of "pursuing power generation (MPPT zone)" and "pursuing safety (constant power zone)" are completely separated in both time and speed dimensions, avoiding mutual interference between control logics. Furthermore, by explicitly determining the standby state, the dynamic probing in step S3 is avoided from being frequently executed by the unit in the low-speed range (when wind energy is very low). This not only saves the controller's computing resources but also avoids unnecessary oscillations and wear in the drivetrain caused by frequent torque adjustments at low wind speeds. Further, through the rigorous determination in this step, it is ensured that temperature-based over-generation determination is only allowed after the unit has truly entered the constant power control zone and the speed has stabilized. This prevents the unit from mistakenly entering over-generation mode before the speed has stabilized (while still climbing in the MPPT zone), thus ensuring control safety.

[0042] See also Figure 1 When the method reaches step S3, that is, when it is determined that it is in the maximum power tracking zone, the first torque command is generated by using dynamic step size probing logic based on the relationship between the speed change and power change of the previous control cycle and the current control cycle.

[0043] Specifically, in this process, the dynamic step size probing logic can include a forward step size adjustment logic step, a reverse step size adjustment logic step, and a dead zone locking logic step.

[0044] For the positive step size adjustment logic step, if the generator speed in the current cycle is greater than the generator speed in the previous cycle, and the generator power in the current cycle is greater than the generator power in the previous cycle, then the torque increase direction is determined to be correct. Based on the current electromagnetic torque command, a positive preset step size is added to generate the first torque command.

[0045] For the reverse step adjustment logic step, if the generator speed in the current cycle is less than the generator speed in the previous cycle, and the generator power in the current cycle is less than the generator power in the previous cycle, it is determined that the torque is too large, causing the speed to drop. Then, a reverse backoff step is subtracted from the current electromagnetic torque command to generate the first torque command.

[0046] For the dead-zone locking logic step, if the generator speed in the current cycle is greater than the generator speed in the previous cycle, but the generator power change in the current cycle is less than the preset dead-zone threshold, then it is determined that the power is close to the limit, and the current torque command is kept unchanged as the first torque command.

[0047] In step S3 of this invention, the controller no longer relies on a preset power curve or wind speed-rotation speed mapping table, but instead uses a trial-feedback-correction closed-loop logic to find the optimal operating point in real time. The specific execution flow is as follows.

[0048] First, periodic state sampling and data buffering are performed. The controller reads the generator speed value ωnew and output power value Pnew at the current time T at a preset time interval (e.g., every 50ms) as a control cycle. Then, it retrieves the generator speed value ωold and output power value Pold from the previous time T-1 from the memory register.

[0049] Next, the system first determines whether the unit is in an energy-increasing phase, i.e., a positive step-up adjustment logic. Specifically, it calculates the speed difference Δω = ωnew - ωold and the power difference ΔP = Pnew - Pold. If Δω > 0 (speed increases) and ΔP > 0 (power increases), it indicates that the current wind energy is sufficient, and the torque setting of the previous cycle has not reached its limit; the rotor is still accelerating, and the power increases accordingly. At this point, the system determines that the torque increase direction is correct. Then, a positive preset step size (Step_Up) is superimposed on the electromagnetic torque command of the previous cycle. For example: New_Torque = Old_Torque + 50 Nm. The purpose of this is to attempt to further increase the generator load to capture more wind energy and approach the power limit point.

[0050] The system then determines whether the unit is in an overload stall risk state, i.e., the reverse step size adjustment logic. This is a key protection logic to prevent the unit from being dragged down. Specifically, if Δω < 0 (speed decrease) and ΔP < 0 (power decrease), it indicates that the torque applied in the previous cycle was too large, exceeding the aerodynamic torque that the blades can provide at the current wind speed, causing the rotor kinetic energy to be overdrawn, and both speed and power to drop. At this time, a rapid backoff operation is immediately executed, subtracting a reverse backoff step size (Step_Back) from the current electromagnetic torque command. It should be noted here that, in order to prevent the stall from worsening, the reverse backoff step size is usually set slightly larger than the forward step size (e.g., Step_Back = 2Step_Up) to ensure that the speed can recover quickly. The purpose of this is to reduce the generator load, allow the impeller to accelerate again, and return to the optimal tip speed ratio range.

[0051] The system ultimately determines whether the unit has reached a stable saturation point to avoid repeated oscillations near the optimal operating point. Specifically, if Δω > 0 (slight increase in speed), but |ΔP| < the preset dead zone threshold (extremely small power change), it indicates that although the rotor is still accelerating, the power is hardly increasing anymore, meaning the unit is already operating in the flat-top region of the power-speed curve (i.e., near the highest efficiency point). Continuing to increase torque will only increase mechanical stress without bringing significant power generation gains. At this point, the current electromagnetic torque command is locked, neither increased nor decreased, maintaining the operating point unchanged. The corresponding unlocking condition is: this locked state will remain until the wind speed sensor detects a wind speed change exceeding the preset environmental fluctuation threshold, at which point the system will reactivate the aforementioned probing logic.

[0052] As can be seen from the above embodiments, step S3 of the present invention controls solely based on the relative changing trends of rotational speed and power. Regardless of whether the blades are dirty or how the air density changes, as long as the logic of increasing rotational speed and increasing power is satisfied, the system can automatically find the maximum power point under the current conditions. This makes the control accuracy unaffected by environmental parameter drift. In addition, by using reverse stop-loss and a large backoff step size, aerodynamic stall of the unit can be effectively prevented when the wind speed drops suddenly, ensuring safety. Furthermore, by locking the dead zone, frequent torque adjustments of the converter due to small sampling noise near the optimal operating point are avoided, reducing mechanical wear of the drive train and power fluctuations on the grid side. Moreover, the above S3 step does not involve any complex exponential calculations, differential equation solutions, or matrix operations, which means that the algorithm can be directly run on extremely low-cost industrial control chips or in the PLC retrofit of old wind turbines without upgrading the hardware controller.

[0053] See further details Figure 1 If the method proceeds to step S4, i.e. when it is determined that the constant power control zone is in place, the upper limit setting value of the power is dynamically adjusted based on the comparison results between the generator state parameters and the converter state parameters and the preset temperature boundary, so as to generate the second torque command.

[0054] Specifically, in step S4, the generator stator temperature and the converter IGBT temperature are first read, and then the judgment process described below is executed.

[0055] If the generator stator temperature and the converter IGBT temperature are both lower than the preset safety warning temperature, and the ambient temperature is lower than the preset low temperature threshold, the power upper limit setting will be increased to 105% of the rated power, and a second torque command will be generated based on the adjusted power upper limit setting.

[0056] If either the generator stator temperature or the converter IGBT temperature exceeds the safety warning temperature, or if the detected temperature rise rate exceeds the preset temperature rise slope threshold, the power upper limit setting will be adjusted back to 100% of the rated power, and a second torque command will be generated based on the adjusted power upper limit setting.

[0057] If the generator stator temperature or converter IGBT temperature continues to rise and approaches the fault trip temperature, the power upper limit setting will be reduced to 80% of the rated power, and a second torque command will be generated based on the adjusted power upper limit setting.

[0058] Specifically, after determining in step S2 that the wind turbine's rotational speed is close to or has reached its rated speed, thus entering the constant power control zone, the system no longer simply clamps the power to a fixed rated value (e.g., 2MW), but instead performs the dynamic power adjustment based on the thermal capacity boundary as described in step S4. This step utilizes the thermal inertia and heat dissipation margin of the generator and converter to achieve dynamic fluctuation of the power upper limit through the following logical sub-steps.

[0059] First, real-time monitoring of temperature data and setting of thresholds are implemented. The system reads the generator stator temperature (Tstator) and the converter IGBT module temperature (Tigbt) in real time. Simultaneously, the system internally presets three types of key temperature thresholds: Low temperature threshold: used to determine whether the external environment is conducive to heat dissipation (e.g., 0℃ or -10℃). Safety warning temperature: The soft boundary for long-term stable operation of the equipment (e.g., 75℃), which is lower than the fault trip value; Fault trip temperature: The hard boundary for equipment protection shutdown (e.g., 90°C).

[0060] Next, the system first determines whether to increase speed and efficiency. Specifically, if both Tstator and Tigbt are below the preset safety warning temperature, and the ambient temperature is below the preset low-temperature threshold (indicating it's winter or a cold night, and the equipment has excellent natural heat dissipation), the system determines that the unit has a large thermal capacity margin and automatically activates the power optimization mode. At this point, the controller breaks the limit, increasing the power upper limit setting from the rated power (100%) to 105% of the rated power (allowing for short-term over-generation). This process utilizes the physical characteristic that heat generated by copper and iron losses can be quickly carried away in low-temperature environments.

[0061] While the unit is operating at 105% power, the system continuously monitors temperature changes at high frequency. If either the Tstator or Tigbt value exceeds the safety warning temperature, or even if the absolute temperature is within the safe range but the system-calculated temperature rise rate (°C / min) exceeds the preset temperature rise slope threshold (indicating that the temperature rise is too rapid and the cooling system may not be able to balance the current heat generation), the system determines that the thermal margin has been exhausted and immediately exits the power optimization mode. At this time, the control command forcibly reverts the power upper limit setting from 105% to 100% of the rated power to prevent equipment overheating and damage.

[0062] When the unit is operating at rated power and encounters extreme high temperatures or a decline in the performance of the cooling system (such as filter clogging), a survival-first logic is executed. At this time, if Tstator or Tigbt shows a continuous upward trend and the value is approaching the fault trip temperature (e.g., reaching 95% of the trip value), the system does not wait for a fault to occur but instead preemptively executes an "active load reduction strategy." The controller drastically reduces the power limit setting from 100% to 80% of the rated power. By actively reducing current output, Joule heating is reduced at its source, using the reduced load to allow the unit to operate without stopping.

[0063] After determining the adjusted power upper limit setting value through the above process, the system calculates the corresponding second torque command through the following process: second torque command = dynamically adjusted power upper limit value / current generator speed.

[0064] By executing the above steps, and ensuring safety, a 5% power overload is achieved by utilizing the thermal margin of the low-temperature environment. For wind farms with low average annual temperatures, this can significantly increase annual power generation and boost economic benefits. Furthermore, this invention employs a "proactive load reduction to 80%" strategy, intervening proactively before the temperature critical point. Although this sacrifices 20% of power, it retains 80% of the generating capacity, avoiding significant losses from downtime and improving the unit's online availability. Moreover, this invention introduces a temperature rise rate judgment logic, enabling it to exit the overload mode in advance when the temperature trend has already worsened (e.g., a sudden temperature rise due to cooling fan failure), even before the temperature has deteriorated. This predictive control effectively avoids temperature overshoot caused by thermal inertia, extending the service life of the generator insulation and converter power modules. Furthermore, this process does not rely on complex aerodynamic formulas or motor thermal models, exhibiting strong robustness and universality.

[0065] Furthermore, in an embodiment of the present invention, during the execution of the above steps, the present invention will simultaneously execute step S5, that is, calculate the vibration amplitude based on the unit vibration parameters, and when the vibration amplitude enters the warning range, perform avoidance adjustment in combination with the current generator speed or pitch rate to generate a third torque command.

[0066] Specifically, the vibration amplitude calculation, as described above, is based on the collected vibration amplitudes along the X-axis and Y-axis of the tower. The root mean square (RMS) values ​​of the vibration acceleration in the front-to-back and left-to-right directions of the tower are then calculated as the vibration amplitude. When the vibration amplitude enters the warning range, the system determines whether the current generator speed is within the preset tower resonance speed band. If yes, a forced jump torque value is generated as the third torque command to drive the generator speed to cross the resonance speed band at the maximum allowable acceleration. If no, the pitch rate is checked. If the pitch rate is greater than a preset high-frequency threshold, a hold command to maintain the current torque is generated as the third torque command, and simultaneously, a command to reduce pitch sensitivity is sent to the pitch system.

[0067] In this step, tower vibration is no longer treated merely as a trigger signal for a fault shutdown, but rather as a limiting control variable introduced into the closed-loop control. By distinguishing the source of the vibration (whether it is structural resonance or excessive pitch control), targeted suppression measures are taken, thereby ensuring continued operation of the unit without triggering an alarm shutdown.

[0068] Specifically, the system first reads the data from the accelerometer and decomposes the acquired raw vibration signal into components in two orthogonal directions: X-axis component (Fore-Aft): This is the forward and backward direction of the tower (with the wind), and is mainly affected by thrust fluctuations. Y-axis component (Side-Side): This refers to the left and right (lateral) direction of the tower, which is mainly affected by yaw moment and unbalanced force.

[0069] The root mean square (RMS) values ​​of the signals in the two directions are calculated to obtain the current real-time vibration amplitudes Vx_rms and Vy_rms.

[0070] The system has two preset vibration thresholds: a warning threshold (e.g., 0.15g) and a shutdown threshold (e.g., 0.25g). If Vx_rms or Vy_rms exceeds the shutdown threshold, a safety chain shutdown is triggered directly. If Vx_rms or Vy_rms is between the warning threshold and the shutdown threshold (i.e., entering the warning range), subsequent active avoidance adjustment logic is triggered. When the vibration is within the warning range, the control system immediately checks the current real-time generator speed. The system internally stores a preset tower resonance speed band (e.g., 10.5rpm - 11.5rpm), which corresponds to the first natural frequency of the tower. If the current speed falls within this resonance speed band, the system determines that the current vibration is caused by structural resonance. At this time, a third torque command is generated, which requires a step adjustment of the electromagnetic torque (usually a rapid reduction in torque to allow the rotor to accelerate through, or an increase in torque to allow the rotor to decelerate away), forcing the generator speed to quickly jump out of the resonance band, and strictly prohibiting the speed command from remaining within this range. If the vibration is within the warning range, but the current rotational speed is not within the resonant speed band, the system determines that the vibration is not caused by resonance, but may be caused by severe fluctuations in aerodynamic loads (such as turbulent wind or excessive pitch control). In this case, the system reads the pitch rate within the most recent time window. If the pitch rate exceeds a preset high-frequency threshold (indicating that the pitch control is too frequent and severe), the system determines that the pitch system is overreacting, causing tower swaying. At this point, a hold command to maintain the current torque is generated as the third torque command, and a control command is simultaneously generated to forcibly reduce the PID gain coefficient of the pitch system (i.e., reduce sensitivity), slowing down blade movement and using aerodynamic damping to suppress tower vibration.

[0071] The advantage of this approach is that by intervening in control during the warning period before vibration reaches the shutdown threshold, and actively eliminating the vibration source by adjusting torque or pitch strategies, the unit can operate with defects or transition smoothly, reducing unplanned downtime. Furthermore, compared to existing technologies, this invention uses logical judgment to distinguish the physical causes of vibration. If it is resonance, a speed jump is used (avoiding the frequency point); if it is over-control, sensitivity is reduced (damping is increased). This hierarchical logic ensures the targetedness and effectiveness of the control strategy, avoiding erroneous adjustments (e.g., reducing pitch sensitivity during resonance is ineffective). In addition, by logically forcibly preventing the unit from staying within the resonance speed range, it effectively prevents the tower from operating under resonance conditions for extended periods, significantly reducing fatigue damage accumulation in tower welds and foundation bolts.

[0072] Finally, the method of the present invention proceeds to step S6, which involves comprehensively determining the first torque command, the second torque command, and the third torque command, and selecting the minimum value that satisfies all boundary constraints as the final control command. That is, the final torque command is set to the minimum value among the first torque command, the second torque command, and the third torque command, and the final torque command is sent to the converter controller for execution, while the corresponding pitch angle command is sent to the pitch actuator.

[0073] Specifically, within a synchronized clock cycle, the system simultaneously reads the torque request values ​​output by three independent calculation modules: First torque command (Tmppt): Derived from step S3. This is the torque value that the unit wants to output at the current wind speed to maximize power generation efficiency. This value typically fluctuates with wind speed.

[0074] The second torque command (Tthermal): derived from step S4. This is the upper limit of the torque that the unit is allowed to output based on the temperatures of the generator and converter. For example, this value is higher in power-optimized mode and lower in active load-reducing mode.

[0075] The third torque command (Tvibration): originates from step S5. This is the torque boundary limited by the unit to avoid tower resonance or severe swaying. Under normal circumstances, this value is usually the rated torque, but it will be forcibly changed when it is necessary to avoid the resonance zone.

[0076] Then, the controller performs a logical threshold comparison, following the principle of "safety level takes precedence over benefit level". The specific execution logic is as follows: First round of comparison (thermal limit verification): First, compare the first torque command (Tmppt) with the second torque command (Tthermal).

[0077] If Tmppt > Tthermal, it means the current power generation target has exceeded the component's thermal tolerance, and the result is set to Tthermal. If Tmppt ≤ Tthermal, it means the current power generation is within the thermal safety range, and the result is set to Tmppt. The result selected in this round is labeled as the intermediate variable Ttemp.

[0078] The second round of comparison (mechanical limit verification): compare the intermediate variable Ttemp with the third torque command (Tvibration).

[0079] If Ttemp > Tvibration, it means that although the heat is permissible, the current torque will cause the unit to fall into the resonance zone or aggravate vibration, and avoidance must be enforced. The final result is Tvibration. If Ttemp ≤ Tvibration, it means that the current state satisfies both thermal safety and mechanical vibration safety, and the final result is Ttemp.

[0080] The value obtained by comparing the two rounds of values ​​(i.e. taking the minimum value) is the final torque setpoint (Tfinal).

[0081] Once Tfinal is determined, the controller sends the following commands in parallel via fieldbus (such as CANopen or Profinet): Sending to the converter: Using Tfinal as the given target for electromagnetic torque, the converter precisely adjusts the generator current to match this torque by controlling the switching frequency of the IGBTs.

[0082] Send the following message to the pitch system: Since changes in torque will cause fluctuations in generator speed (when torque decreases, speed increases, and when torque increases, speed decreases), the main control system needs to calculate the feedforward pitch angle that matches Tfinal and notify the pitch motor to fine-tune the blade angle to prevent generator overspeed caused by sudden torque limitation (such as triggering thermal protection to reduce load).

[0083] In this way, through continuous numerical comparisons (taking the minimum value), the transition from "MPPT mode" to "thermal protection mode" or "vibration avoidance mode" is a smooth numerical handover process. For example, as the temperature rises, Tthermal gradually decreases. When it falls below Tmppt, control is naturally and smoothly transferred to the thermal protection logic without any hard logic switching, greatly improving the stability of the control system. Furthermore, this logic ensures that the unit always operates on the most critical physical bottleneck. If the current bottleneck is wind energy (low wind), and Tmppt is at its minimum, the unit will capture wind energy at full capacity; if the current bottleneck is temperature (hot weather), and Tthermal is at its minimum, the unit will generate the most electricity without overheating; if the current bottleneck is vibration (resonance), and Tvibration is at its minimum, the unit will maintain operation without vibration. This mechanism avoids mechanical and forced protective shutdowns, transforming passive shutdowns into proactive adaptations, significantly increasing the unit's annual power generation.

[0084] On the other hand, such as Figure 2 As shown, the present invention also provides a wind turbine power optimization control system, which includes: The data acquisition module collects real-time operating data of the wind turbine. The state division module compares the collected generator speed with the preset cut-in speed and rated speed to divide the wind turbine's operating state into standby state, maximum power tracking zone, and constant power control zone. The instruction generation module, when determining that it is in the maximum power tracking zone, generates a first torque instruction based on the relationship between the speed and power changes in the previous and current control cycles using dynamic step-size probing logic; when determining that it is in the constant power control zone, it dynamically adjusts the upper power limit setting based on the comparison results between the generator state parameters, converter state parameters and the preset temperature boundary to generate a second torque instruction; it calculates the vibration amplitude based on the unit vibration parameters, and when the vibration amplitude enters the warning range, it performs avoidance adjustment in combination with the current generator speed or pitch rate to generate a third torque instruction; The command output module comprehensively judges the first torque command, the second torque command, and the third torque command, and selects the minimum value that satisfies all boundary constraints as the final control command.

[0085] The specific applications of this system can be compared with the methods described above.

[0086] Figure 3 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 3 As shown, the electronic device may include a processor 810, a communications interface 820, a memory 830, and a communication bus 840. The processor 810, communications interface 820, and memory 830 communicate with each other via the communication bus 840. The processor 810 can call logic instructions from the memory 830 to execute the wind turbine power optimization control method described above.

[0087] Furthermore, the logical instructions in the aforementioned memory 830 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) 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 USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0088] On the other hand, the present invention also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the wind turbine power optimization control method provided by the above methods.

[0089] In another aspect, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to perform the wind turbine power optimization control methods provided by the methods described above.

[0090] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0091] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for optimizing the power control of a wind turbine generator set, characterized in that, include: Step S1: Collect real-time operating data of the wind turbine; Step S2: Compare the collected generator speed with the preset cut-in speed and rated speed to divide the wind turbine's operating state into standby state, maximum power tracking zone and constant power control zone; Step S3: When it is determined that the maximum power tracking zone is in, the first torque command is generated by using dynamic step size probing logic based on the relationship between the speed change and power change between the previous control cycle and the current control cycle. Step S4: When it is determined that the constant power control zone is in place, the upper limit setting value of the power is dynamically adjusted based on the comparison results of the generator state parameters and converter state parameters with the preset temperature boundary to generate the second torque command; Step S5: Calculate the vibration amplitude based on the unit vibration parameters. When the vibration amplitude enters the warning range, perform avoidance adjustment in combination with the current generator speed or pitch rate to generate a third torque command. Step S6: Perform a comprehensive judgment on the first torque command, the second torque command, and the third torque command, and select the minimum value that satisfies all boundary constraints as the final control command.

2. The wind turbine power optimization control method according to claim 1, characterized in that, In step S1, the running data includes: Environmental parameters, including ambient temperature and wind speed; Generator status parameters, including generator speed and generator stator temperature; Converter status parameters, including converter IGBT temperature; The unit's vibration parameters include the vibration amplitude of the tower in the X-axis direction and the vibration amplitude of the tower in the Y-axis direction.

3. The wind turbine power optimization control method according to claim 2, characterized in that, Step S2 specifically includes: If the current generator speed is less than the cut-in speed, it is determined to be in standby mode and power optimization will not be performed. If the current generator speed is greater than or equal to the cut-in speed and less than the rated speed, it is determined to be in the maximum power tracking zone, and proceed to step S3; If the current generator speed reaches the rated speed, it is determined to be in the constant power control zone, and proceed to step S4.

4. The wind turbine power optimization control method according to claim 2, characterized in that, In step S3, the dynamic step size probing logic includes a positive step size adjustment logic step: If the generator speed in the current cycle is greater than the generator speed in the previous cycle, and the generator power in the current cycle is greater than the generator power in the previous cycle, then the direction of torque increase is determined to be correct. A positive preset step size is added to the current electromagnetic torque command to generate the first torque command. Furthermore, in step S3, the dynamic step size probing logic also includes a reverse step size adjustment logic step: If the generator speed in the current cycle is less than the generator speed in the previous cycle, and the generator power in the current cycle is less than the generator power in the previous cycle, then it is determined that the torque is too large, causing the speed to drop. Based on the current electromagnetic torque command, a reverse backoff step is subtracted to generate the first torque command.

5. The wind turbine power optimization control method according to claim 4, characterized in that, In step S3, the dynamic step-size probing logic further includes a dead-zone locking logic step: If the generator speed in the current cycle is greater than the generator speed in the previous cycle, but the generator power change in the current cycle is less than the preset dead zone threshold, then the power is determined to be close to the limit, and the current torque command is kept unchanged as the first torque command.

6. The wind turbine power optimization control method according to claim 2, characterized in that, Step S4 specifically includes: Read the generator stator temperature and converter IGBT temperature; If the generator stator temperature and the converter IGBT temperature are both lower than the preset safety warning temperature, and the ambient temperature is lower than the preset low temperature threshold, the power upper limit setting will be increased to 105% of the rated power, and a second torque command will be generated based on the adjusted power upper limit setting. If either the generator stator temperature or the converter IGBT temperature exceeds the safety warning temperature, or if the temperature rise rate is detected to be greater than the preset temperature rise slope threshold, the power upper limit setting will be adjusted back to 100% of the rated power, and a second torque command will be generated based on the adjusted power upper limit setting. If the generator stator temperature or converter IGBT temperature continues to rise and approaches the fault trip temperature, the power upper limit setting will be reduced to 80% of the rated power, and a second torque command will be generated based on the adjusted power upper limit setting.

7. The wind turbine power optimization control method according to claim 2, characterized in that, In step S5, the calculation of the vibration amplitude specifically involves: Based on the collected vibration amplitudes of the tower along the X-axis and Y-axis, the root mean square values ​​of the vibration accelerations in the front-back and left-right directions of the tower are calculated and used as the vibration amplitudes.

8. The wind turbine power optimization control method according to claim 7, characterized in that, Step S5 specifically includes: When the vibration amplitude enters the warning range, determine whether the current generator speed is within the preset tower resonance speed band; If the result is yes, a forced jump torque value is generated as the third torque command to drive the generator speed to cross the resonant speed band at the maximum allowable acceleration; If the result is negative, the pitch rate is checked. If the pitch rate is greater than a preset high-frequency threshold, a hold command to maintain the current torque is generated as the third torque command, and a command to reduce pitch sensitivity is sent to the pitch system at the same time.

9. The wind turbine power optimization control method according to claim 1, characterized in that, Step S6 specifically includes: Set the final torque command to be equal to the minimum value among the first torque command, the second torque command, and the third torque command; The final torque command is sent to the converter controller for execution, and the corresponding pitch angle command is sent to the pitch actuator.

10. A wind turbine power optimization control system, characterized in that, include: The data acquisition module collects real-time operating data of the wind turbine. The state division module compares the collected generator speed with the preset cut-in speed and rated speed to divide the wind turbine's operating state into standby state, maximum power tracking zone, and constant power control zone. The instruction generation module, when determining that it is in the maximum power tracking zone, generates a first torque instruction based on the relationship between the speed and power changes in the previous and current control cycles using dynamic step-size probing logic; when determining that it is in the constant power control zone, it dynamically adjusts the upper power limit setting based on the comparison results between the generator state parameters and converter state parameters and the preset temperature boundary to generate a second torque instruction; it calculates the vibration amplitude based on the unit vibration parameters, and when the vibration amplitude enters the warning range, it performs avoidance adjustment in combination with the current generator speed or pitch rate to generate a third torque instruction; The command output module comprehensively judges the first torque command, the second torque command, and the third torque command, and selects the minimum value that satisfies all boundary constraints as the final control command.

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