Position sensor fault processing method and related device

Abstract

The embodiment of the present application provides a position sensor fault handling method and related devices, which relate to the field of wind power generation technology. The method includes: obtaining a fault detection result, the fault detection result is used to indicate whether the position sensor is faulty; when the fault detection result indicates that the position sensor is faulty, using a speed observer to obtain a motor predicted speed; according to the motor predicted speed, obtain a motor predicted position; according to the motor predicted position, obtain a blade predicted position, and control the motor according to a retracting instruction, a motor predicted speed corresponding to the motor predicted position, and a blade predicted position, so that the blade predicted position reaches a preset position, and the motor continues to run in the process of controlling the motor to make the blade predicted position reach the preset position. In this way, when it is determined that the position sensor is faulty, the retracting can be completed without stopping and restarting, which has the characteristics of fast and efficient.

Description

Technical Field

[0001] The present application relates to the technical field of wind power generation, and in particular to a position sensor fault processing method and related devices. Background Art

[0002] When the wind turbine electric pitch system is changing the pitch according to the system instructions, it is necessary to obtain the motor position, motor speed, etc. through the position sensor installed on the motor for closed-loop control to achieve pitch control. If the position sensor fails, the pitch system needs to retract the pitch urgently to ensure safety. Therefore, how to complete the retraction when the position sensor fails has become a technical problem that technicians in this field need to solve urgently. Summary of the invention

[0003] The embodiment of the present application provides a position sensor fault processing method and related device, which can complete propeller retraction without stopping and restarting when a position sensor fault is determined, and has the characteristics of fast and efficient.

[0004] The embodiments of the present application can be implemented as follows:

[0005] In a first aspect, an embodiment of the present application provides a position sensor fault processing method, the method comprising:

[0006] Obtaining a fault detection result, wherein the fault detection result is used to indicate whether the position sensor is faulty;

[0007] When the fault detection result indicates that the position sensor is faulty, using a speed observer to obtain a predicted motor speed;

[0008] Obtaining a predicted position of the motor according to the predicted speed of the motor;

[0009] The predicted blade position is obtained based on the predicted motor position, and the motor is controlled based on the retraction instruction, the predicted motor speed corresponding to the predicted motor position, and the predicted blade position, so that the predicted blade position reaches a preset position, wherein the motor continues to run during the process of controlling the motor to make the predicted blade position reach the preset position.

[0010] In a second aspect, an embodiment of the present application provides a position sensor fault processing device, the device comprising:

[0011] A result obtaining module, used to obtain a fault detection result, wherein the fault detection result is used to indicate whether the position sensor is faulty;

[0012] A processing module, configured to obtain a predicted motor speed by using a speed observer when the fault detection result indicates that the position sensor is faulty;

[0013] The processing module is further used to obtain a predicted position of the motor according to the predicted speed of the motor;

[0014] The processing module is also used to obtain the predicted blade position based on the predicted motor position, and control the motor according to the retraction instruction, the predicted motor speed corresponding to the predicted motor position, and the predicted blade position, so that the predicted blade position reaches a preset position, wherein the motor continues to run during the process of controlling the motor to make the predicted blade position reach the preset position.

[0015] In a third aspect, an embodiment of the present application provides an electronic device, including a processor and a memory, wherein the memory stores machine executable instructions that can be executed by the processor, and the processor can execute the machine executable instructions to implement the position sensor fault handling method described in the aforementioned embodiment.

[0016] In a fourth aspect, an embodiment of the present application provides a readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the position sensor fault handling method as described in the aforementioned embodiment is implemented.

[0017] The position sensor fault handling method and related device provided in the embodiment of the present application first obtain a fault detection result, which is used to indicate whether the position sensor used to obtain the motor position in the wind turbine pitch control system is faulty; when the fault detection result indicates that the position sensor is faulty, the speed observer is used to obtain the motor predicted speed; the motor predicted position is obtained according to the motor predicted speed, and then the blade predicted position is obtained according to the motor predicted position, and the motor is controlled according to the retraction instruction, the motor predicted speed corresponding to the motor predicted position, and the blade predicted position, so that the blade predicted position reaches the preset position. Among them, the motor continues to run during the process of controlling the motor to make the blade predicted position reach the preset position. In this way, when it is determined that the position sensor is faulty, the retraction can be completed without stopping and restarting, which has the characteristics of fast and efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 A block diagram of an electronic device provided in an embodiment of the present application;

[0020] Figure 2One of the flow charts of the position sensor fault processing method provided in the embodiment of the present application;

[0021] Figure 3 for Figure 2 A schematic flow chart of the sub-steps included in step S110;

[0022] Figure 4 for Figure 2 One of the flowchart diagrams of the sub-steps included in step S140;

[0023] Figure 5 for Figure 2 2 is a flow chart of the sub-steps included in step S140;

[0024] Figure 6 for Figure 2 3. Flow chart of sub-steps included in step S150;

[0025] Figure 7 The second flowchart of the position sensor fault processing method provided in the embodiment of the present application;

[0026] Figure 8 One of the schematic diagrams for illustrating an embodiment of the present application;

[0027] Fig. 9 The second schematic diagram for illustrating an embodiment of the present application is provided;

[0028] Fig.10 A block diagram of a position sensor fault processing device provided in an embodiment of the present application.

[0029] Icons: 100 - electronic device; 110 - memory; 120 - processor; 130 - communication unit; 200 - position sensor fault processing device; 210 - result acquisition module; 220 - processing module. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0031] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0032] It should be noted that relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0033] If it is determined that the position sensor causes the propeller to be retracted, the motor can be stopped by the brake first, and then the motor positioning open loop can be started. After that, the motor can be controlled to rotate at a certain speed until the blade triggers the switch corresponding to the completion of the propeller retraction. However, the above-mentioned method of switching after the position sensor fails and needs to be stopped and restarted has problems such as heavy loads on the blade root and the main shaft and a long time consumption.

[0034] In response to the above situation, an embodiment of the present application provides a position sensor fault handling method and related devices. When a position sensor fault is determined, controlled retraction can be performed based on the prediction information and retraction instructions without shutting down and restarting. It is fast and efficient, and can reduce the blade root and main shaft load.

[0035] In conjunction with the accompanying drawings, some embodiments of the present application are described in detail below. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0036] Please refer to Figure 1 , Figure 1 A block diagram of an electronic device 100 provided in an embodiment of the present application. The electronic device 100 may be, but is not limited to, a control device in a wind turbine, etc. The electronic device 100 may include a memory 110, a processor 120, and a communication unit 130. The memory 110, the processor 120, and the communication unit 130 are electrically connected to each other directly or indirectly to achieve data transmission or interaction. For example, these components may be electrically connected to each other via one or more communication buses or signal lines.

[0037] The memory 110 is used to store programs or data. The memory 110 may be, but is not limited to, a random access memory (RAM), a read only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), etc.

[0038] The processor 120 is used to read / write data or programs stored in the memory 110 and execute corresponding functions. For example, the memory 110 stores a position sensor fault processing device 200, and the position sensor fault processing device 200 includes at least one software function module that can be stored in the memory 110 in the form of software or firmware. The processor 120 executes various functional applications and data processing by running software programs and modules stored in the memory 110, such as the position sensor fault processing device 200 in the embodiment of the present application, that is, realizing the position sensor fault processing method in the embodiment of the present application.

[0039] The communication unit 130 is used to establish a communication connection between the electronic device 100 and other communication terminals through a network, and to send and receive data through the network.

[0040] It should be understood that Figure 1 The structure shown is only a schematic diagram of the structure of the electronic device 100. The electronic device 100 may also include Figure 1 More or fewer components as shown, or with Figure 1 Different configurations are shown. Figure 1 Each component shown in the figure can be implemented by hardware, software or a combination thereof.

[0041] Please refer to Figure 2 , Figure 2 This is one of the flow diagrams of the position sensor fault handling method provided in the embodiment of the present application. The method can be applied to the above-mentioned electronic device. The specific flow of the position sensor fault handling method is described in detail below. In this embodiment, the method may include steps S110 to S140.

[0042] Step S110, obtaining a fault detection result.

[0043] The wind turbine pitch control system includes a motor and a position sensor, and the position sensor is used to obtain the motor position and motor speed of the motor. The position sensor can be, but is not limited to, an encoder, a rotary transformer, an induction synchronizer, etc. A fault detection result corresponding to the position sensor can be obtained. The fault detection result can be manually input, can be detected and sent by other devices, or can be obtained by other means, for example, the fault detection result can be obtained according to historical records at startup. The fault detection result is used to indicate whether the position sensor is faulty.

[0044] Step S120: when the fault detection result indicates that the position sensor is faulty, using a speed observer to obtain a predicted motor speed.

[0045] Step S130, obtaining a predicted motor position according to the predicted motor speed.

[0046] Step S140, obtaining the predicted blade position according to the predicted motor position, and controlling the motor according to the retraction instruction, the predicted motor speed corresponding to the predicted motor position, and the predicted blade position, so that the predicted blade position reaches a preset position.

[0047] When the fault detection result obtained indicates that the position sensor is faulty, the sensorless operation mode can be directly entered, or it can be determined whether to enter the sensorless operation mode in combination with other requirements. The sensorless operation mode refers to a mode of operation without a position sensor, that is, operation not based on the data of the position sensor. The normal operation mode refers to a mode of operation with a position sensor, that is, operation based on the data of the position sensor. If it is determined not to enter the sensorless operation mode, the normal operation mode can be executed according to the data of the position sensor.

[0048] If the sensorless operation mode is entered, the following processing can be continuously performed: the motor predicted speed is obtained based on the pre-acquired speed observer, and the motor predicted position is obtained according to the motor predicted speed, and then the blade predicted position is obtained according to the motor predicted position, and the motor is controlled according to the retraction instruction, the motor predicted speed corresponding to the motor predicted position, and the blade predicted position, so that the blade predicted position reaches the preset position. When the blade predicted position reaches the preset position, the brake can be applied to stop the motor, so that the retraction can be completed. In the retraction process of the sensorless operation mode, the motor continues to run, that is, the motor continues to run in the process of controlling the motor to make the blade predicted position reach the preset position. Among them, the preset position indicates the safe position of the blade, for example, 89°, which can be set according to actual needs.

[0049] In this way, the system can enter the sensorless operation mode after a position sensor failure. In this mode, the motor is controlled based on the predicted motor speed, predicted motor position, predicted blade position and retraction command, thereby completing the rapid switching from position sensor failure to retraction through a command following and sensorless switching method. Furthermore, since there is no shutdown and restart, there will be no heavy load on the blade root and main shaft caused by emergency stop or emergency start, so load reduction can be achieved to ensure the safety of the blade root and blades.

[0050] The speed observer can be obtained in advance. The speed observer can be trained based on the motor-related parameters obtained and the motor speed corresponding to the motor-related parameters. Optionally, during the training process, the motor speed output by the speed observer (i.e., the motor speed) can be compared with the motor speed output by the position sensor, and the control parameters can be verified so that the identified speed reaches a level of one thousandth.

[0051] As a possible implementation, the speed observer can be implemented by a flux observer. Principle of the flux observer: By observing the voltage command and feedback (ie, the feedback voltage and the actual voltage) of the motor, the speed of the motor can be identified in real time.

[0052] Optionally, during operation, the speed observer can be continuously used to obtain the motor predicted speed and motor predicted position, and then the obtained predicted information can be used to determine whether the position sensor is faulty, so as to ensure that safe and reliable data is used when controlling based on the position sensor data. After each motor predicted speed is obtained, the corresponding motor reference speed obtained by the position sensor can be compared. If the difference between the two is greater than the preset speed difference, it can be determined that the position sensor is faulty; if the difference between the two is not greater than the preset speed difference, it can be determined that the position sensor is not faulty. Alternatively, after each motor predicted position is obtained, the corresponding motor reference position obtained by the position sensor can be compared. If the difference between the two is greater than the preset position difference, it can be determined that the position sensor is faulty; if the difference between the two is not greater than the preset position difference, it can be determined that the position sensor is not faulty. Alternatively, after each motor predicted speed and corresponding motor predicted position are obtained, the corresponding motor reference speed and motor reference position obtained by the position sensor can be compared. If the speed difference is greater than the preset speed difference and the position difference is greater than the preset position difference, it can be determined that the position sensor is faulty; otherwise, it can be determined that the position sensor is not faulty.

[0053] Optionally, during operation, you can also Figure 3 The fault detection result is obtained in the manner shown. Figure 3 , Figure 3 for Figure 2Schematic diagram of the flow of sub-steps included in step S110. In this embodiment, step S110 may include sub-steps S111 to S113.

[0054] Sub-step S111 , periodically obtaining the motor predicted speed and the motor predicted position according to a first preset period.

[0055] Sub-step S112, according to the second preset period, periodically calculates the speed difference between the current motor predicted speed and the motor reference speed, and the position difference between the current motor predicted position and the motor reference position, and determines whether the speed difference is greater than the preset speed difference, and whether the position difference is greater than the preset position difference.

[0056] Sub-step S113: if the speed difference is greater than the preset speed difference and the position difference is greater than the preset position difference, it is determined that the position sensor is faulty.

[0057] In this embodiment, the motor predicted speed and motor predicted position can be periodically obtained through the speed observer according to the first preset period, that is, the motor predicted speed and motor predicted position are periodically refreshed according to the first preset period. The motor speed and motor position obtained through the position sensor data are also obtained, and the motor speed obtained through the position sensor data can be used as the motor reference speed, and the motor position obtained through the position sensor data can be used as the motor reference position.

[0058] The speed difference between the current predicted motor speed and the reference motor speed, and the position difference between the current predicted motor position and the reference motor position can also be periodically calculated according to the second preset period, and then it is determined whether the speed difference is greater than the preset speed difference, and whether the position difference is greater than the preset position difference. The second preset period is greater than the first preset period, for example, the first preset period is 0.25ms, and the second preset period is 10ms.

[0059] If the speed difference is greater than the preset speed difference and the position difference is greater than the preset position difference, it can be determined that the position sensor is faulty, otherwise it can be determined that the position sensor is not faulty. In this way, by setting the second preset period to be greater than the first preset period, when a certain data jumps, the data can be filtered out, which can reduce misjudgment.

[0060] Optionally, the motor predicted speed or motor predicted position may be periodically obtained according to the first preset period; the speed difference between the current motor predicted speed and the motor reference speed may be periodically calculated according to the second preset period, or the position difference between the current motor predicted position and the motor reference position may be calculated. If the speed difference is greater than the preset speed difference, it is determined that the position sensor is faulty, otherwise it is determined that the position sensor is not faulty. If the position difference is greater than the preset position difference, it is determined that the position sensor is faulty, otherwise it is determined that the position sensor is not faulty.

[0061] If this is the startup time, the fault detection result can be obtained based on historical record analysis.

[0062] After obtaining the fault detection result, if the fault detection result indicates that the position sensor is faulty, the non-sensing operation mode can be directly entered. Alternatively, the jump detection result of the current control signal of the motor can also be obtained, and the jump detection result is used to indicate whether the current control signal jumps abnormally; if the fault detection result indicates that the position sensor is faulty, and the jump detection result indicates that the current control signal jumps abnormally, the non-sensing operation mode can be entered, that is, switched to the non-sensing operation mode; conversely, if the fault detection result indicates that the position sensor is faulty, and the jump detection result indicates that the current control signal does not jump abnormally, the non-sensing operation mode can be not entered, that is, not switched to the non-sensing operation mode, and the normal operation mode can be operated. Among them, whether the current control signal jumps abnormally can be judged by sampling the ammeter, thereby obtaining the jump detection result.

[0063] Please refer to Figure 4 , Figure 4 for Figure 2 One of the flowchart diagrams of the sub-steps included in step S140. In this embodiment, step S140 may include sub-steps S141 to S142.

[0064] Sub-step S141, if the fault detection result indicates that the position sensor is faulty during operation, taking the second blade position before the position sensor fails as a starting point, obtaining the blade predicted position according to the motor predicted position.

[0065] Sub-step S142, controlling the motor according to the retraction instruction, the obtained predicted motor speed, the predicted motor position and the predicted blade position to complete the retraction.

[0066] In this embodiment, if the sensorless operation mode is entered during operation, the blade position before entering the sensorless operation mode can be used as the second blade position, and the second blade position can be used as the starting point to continuously obtain the motor predicted speed through the speed observer, and the motor predicted position can be obtained by integrating the speed, and then the motor predicted position and the second blade position can be accumulated to obtain the current blade predicted position. After that, the motor is controlled according to the retracting instruction, the obtained motor predicted speed, the motor predicted position and the blade predicted position, so that the blade predicted position reaches the preset position.

[0067] The control methods include position loop control and speed loop control. In the position loop control method, the input data is the position command and the predicted blade position obtained through prediction. Based on the above input data, the speed command is obtained through PI (proportional integral) operation, and the speed command enters the speed loop control method. In the speed loop control method, PI control is performed based on the speed command and the predicted motor speed obtained through prediction, and the current module is given a command.

[0068] If the received retracting propeller command is a position command, a speed command can be obtained through a position loop control method based on the position command serving as the retracting propeller command and the predicted blade position; then, based on the speed command, the motor is controlled through a speed loop control method so that the predicted blade position reaches a preset position.

[0069] If the received propeller return instruction is a speed instruction, the motor can be controlled based on the speed instruction as the propeller return instruction so that the predicted position of the blade reaches a preset position.

[0070] The propeller return instruction may be an instruction sent by a master control of the same device, or an instruction sent by other devices, and the specific instruction may be determined in combination with actual needs.

[0071] Please refer to Figure 5 , Figure 5 for Figure 2 FIG. 2 is a flow chart of sub-steps included in step S140. In this embodiment, step S140 may include sub-steps S144 to S145.

[0072] Sub-step S144, if the fault detection result indicates that the position sensor is faulty during startup, the motor is started in an open loop, and the predicted position of the blade is obtained according to the predicted position of the motor during the open loop startup of the motor.

[0073] Sub-step S145, when the obtained motor predicted speed is greater than or equal to the preset speed, the motor is controlled according to the retraction instruction, the obtained motor predicted speed, the motor predicted position and the blade predicted position so that the blade predicted position reaches the preset position.

[0074] In this embodiment, if the sensorless operation mode is entered at startup, the motor can be started in an open loop. The motor open loop start includes positioning and open loop start. Positioning is to position the rotor by a fixed current, and then apply an open loop start current to rotate the rotor. At the same time, the speed observer is used to obtain the predicted motor speed, and to determine whether the predicted motor speed reaches the preset speed. When the preset speed is reached, the following processing is continued: the predicted motor speed, the predicted motor position and the predicted blade position are obtained, and the motor is controlled according to the retraction instruction and the above information so that the predicted blade position reaches the preset position. When the motor is running with a position sensor failure, variable pitch operation can be performed through an open loop start speed sensorless operation scheme to prevent jamming.

[0075] Among them, if the sensorless operation mode is entered at startup, the saved blade position before startup can be used as the first blade position, and then combined with historical records to determine whether the first blade position is credible. If the first blade position is credible, the first blade position can be used as the starting point, and the motor predicted speed continuously obtained during the motor open-loop startup process can be integrated to obtain the motor predicted position, and the current blade predicted position can be obtained by accumulating the motor predicted position and the second blade position.

[0076] If the first blade position is unreliable, integration can be performed based on the motor predicted speed continuously obtained during the motor open-loop startup process, and accumulation can be started from 0 to continuously obtain the blade predicted position.

[0077] When the predicted motor speed reaches the preset speed, the blade position prediction can continue to be performed in an accumulation manner according to the predicted blade position at this time, so as to retract the propeller based on the predicted blade position.

[0078] Among them, the description of how to perform propeller retraction according to the propeller retraction instruction, the obtained motor predicted speed, the motor predicted position and the blade predicted position can be referred to the above description and will not be repeated here. In the case where the propeller retraction instruction is generated by the main control, the blade predicted position can be sent to the main control so that the main control determines the propeller retraction instruction to be used according to the blade predicted position. For example, the main control can determine the specific speed value in the speed instruction as the propeller retraction instruction according to the blade predicted position.

[0079] Please refer to Figure 6 , Figure 6 for Figure 2 FIG. 3 is a flow chart of sub-steps included in step S140. In this embodiment, step S140 may further include sub-steps S147 to S148.

[0080] Sub-step S147, during the control process, when it is determined that the paddle reaches the first target switch, based on the saved correspondence between different switches and different third paddle positions, the third paddle position corresponding to the first target switch is obtained.

[0081] Sub-step S148, updating the current predicted blade position according to the third blade position corresponding to the first target switch.

[0082] In this embodiment, the wind turbine pitch control system also includes a plurality of switches, which may include limit switches and proximity switches. When the position sensor is normal (i.e., without faults), the position of the blade can be determined based on the data of the position sensor, and the blade position obtained at this time is used as the true position of the blade. The true position of the blade when the blade passes through each of the plurality of switches can be recorded, and the true position of the blade obtained at this time can be used as the third blade position. In this way, the correspondence between different switches and different third blade positions can be obtained. The third blade positions corresponding to different switches are obtained by fault-free position sensors.

[0083] In the process of retracting the propeller based on the prediction information, when the propeller reaches a certain switch among the multiple switches, the switch can be used as the first target switch, and the third blade position corresponding to the first target switch can be obtained from the pre-obtained correspondence between different switches and different third blade positions. Then, the current predicted blade position is updated according to the third blade position corresponding to the first target switch. For example, the third blade position corresponding to the first target switch is directly updated to the current predicted blade position. Afterwards, the predicted blade position is obtained again based on the updated predicted blade position and the subsequently obtained predicted motor speed. In this way, the accuracy of the predicted blade position used in the retracting control process can be improved.

[0084] For example, there is a 5-degree proximity switch. When the position sensor is functioning normally, the blade position is determined to be 4.5° when it passes the 5-degree proximity switch based on the sensor data. When the position sensor fails, the predicted blade position is corrected to 4.5° when it passes the 5-degree proximity switch.

[0085] Please refer to Figure 7 , Figure 7 The second flowchart of the position sensor fault processing method provided in the embodiment of the present application is as follows. In this embodiment, the method may further include steps S150 to S160.

[0086] Step S140, when the position sensor recovers from a fault state, controlling the motor so that the blade passes through a second target switch.

[0087] Step S150, when it is determined that the paddle passes through the second target switch, based on the saved correspondence between different switches and different third paddle positions, the third paddle position corresponding to the second target switch is determined, and the current paddle position is updated according to the third paddle position corresponding to the second target switch.

[0088] In this embodiment, the correspondence between different switches and different third blade positions can be saved, and the third blade positions corresponding to different switches are obtained by a fault-free position sensor. In the process of returning the propeller or when the position sensor is restored after it is in place, the propeller can be moved to pass the second target switch. Among them, the second target switch is one of the different switches, which can be determined according to actual needs. When the propeller passes the second target switch, the third blade position corresponding to the second target switch is obtained from the saved correspondence between the different switches and the different third blade positions, and the current blade position is updated based on the third blade position corresponding to the second target switch. Among them, the current predicted blade position is the current blade position. For example, the update method can be: adjusting the current blade position from the predicted blade position to the third blade position corresponding to the second target switch. In this way, when the position sensor fails, it can be switched to the non-sensing operation mode to return the propeller. If the position sensor fails during the process of returning the propeller or after it is in place, the real blade position is calibrated by moving the propeller to a certain switch position, without the need for staff to climb the tower to teach again, reducing the process of personnel climbing the tower.

[0089] The following is an example of the correction described in sub-steps S147 to S147, step S150 and step S160.

[0090] Motor position adopts P motor The blade position is represented by P. pitch express, N represents the number of times the motor rotates 360°, that is, how many times the motor rotates. The transformation ratio is a preset value, generally 2000, so the motor rotates 2000 times and the propeller moves 1°. In the following example, the transformation ratio is 2000.

[0091] Assume that there are two proximity switches: a 5° proximity switch and an 85° proximity switch; and assume that the position sensor is not faulty, when the blade passes the 5° proximity switch, N=10000; when the blade passes the 85° proximity switch, N=170000.

[0092] When the position sensor fails and the sensorless operation mode is entered, the propeller position is obtained by prediction. Calibrate N when the propeller passes the 5° proximity switch or the 85° proximity switch. For example, when the position sensor fails and the sensorless operation mode is entered when the propeller position is 2°, then: N sensorloss =N0+∫speed,Nsensorloss Indicates the number of revolutions of the motor obtained when the position sensor fails, speed indicates the predicted motor speed obtained when the position sensor fails; when passing 5° approaching the switch, N sensorloss It may be 9999 and needs to be calibrated to 10000. The command is given as 180000. When the predicted position of the identified blade is 180000, the propeller return is confirmed to be completed. At this time, it may not be accurate. For example, the actual position may be 180005.

[0093] Assume that after 10 minutes, the position sensor changes from faulty to normal, let: N = N sensor =N sensorloss =180000, N represents the number of revolutions of the motor currently determined, N sensor Indicates the number of revolutions of the motor determined by the position sensor. The propeller moves toward 80 degrees and passes through the 85° proximity switch during the process. N sensor It may be 17005. At this time, execute: N sensor =N 85° =170000.

[0094] In the above-mentioned position sensor fault handling method, the real position sensor is verified through position and speed identification, which facilitates timely detection of position sensor faults. The senseless switching function can quickly and efficiently realize the switching function after the position sensor fails, without stopping and restarting, and the blade stop or speed fluctuation time can be reduced from 5s to less than 0.001s. After the original position sensor fails, the blade angle is no longer controlled, and it can only be stopped by hitting the limit switch through the speed mode; in this embodiment, controlled return can be performed, and the blade root and main shaft load can be reduced by accurately identifying the speed and position. In addition, after a position sensor failure occurs, it is necessary to go back to the tower to verify the blade status; in the embodiment, the blade position corresponding to the switch obtained based on the pre-saved position sensor when there is no fault can be restored to the real position state by itself.

[0095] Combine the following Figure 8 and Fig. 9 The principle of the above position sensor fault handling method is explained.

[0096] The module with position sensor operation is used to operate according to the data of the position sensor.

[0097] Speed ​​position identification module: including speed observer and position identification module. The speed observer uses the state observer to identify the speed and compares it with the speed and / or position measured by the real position sensor to determine whether the position sensor is faulty. The speed observer can be a back-EMF speed observer, which can be used to identify the speed of the motor according to the U d , Uq Perform speed identification.

[0098] Switching module: According to the fault detection result, the position and speed feedback are switched, that is, it is determined whether the value fed back to the control part is the identified value or the value obtained by the position sensor.

[0099] Sensorless operation module: A speed sensorless operation module, an operation mode using real-time speed identification, including a position control module, a speed control module, and an angle control module.

[0100] Speed ​​and position identification module: includes speed observer and position identifier. The speed observer is always observing and identifying the speed. When the position sensor is not faulty, it is compared with the actual speed for cross-verification. The speed is observed and identified through a flux observer. The principle of the flux observer is: the flux observer is used through voltage instructions and feedback to identify the motor speed in real time, and then compared with the speed obtained based on the position sensor. The control parameters are verified so that the identified speed reaches a deviation of one thousandth. When switching to the sensorless operation module, the speed identification module controls the operation according to the initial parameters or the parameters adjusted after the identification comparison. The position identifier completes the motor position identification by integrating the speed, and the identified motor position can be used to represent the blade angle.

[0101] When the position sensor is fault-free, the actual blade angle (i.e., the actual blade position) obtained by the fault-free position sensor during the process of the blade passing through the proximity switch and the limit switch can be recorded. When a position sensor fault occurs, the predicted blade position obtained based on the motor position generated by the speed position identification module can be corrected based on the above-mentioned information.

[0102] The position identification module can compare the speed and / or position data generated by itself with the speed and / or position data obtained by the real position sensor in real time. If the position sensor data jumps abnormally and the current control also jumps abnormally, it switches to the sensorless operation module.

[0103] Switching module: After a sensor failure occurs, the switching module can switch the speed loop and position loop to the sensorless operation module within one PWM cycle; or switch from the sensorless operation module to the normal operation process. The switching module switches the position and speed feedback. The switching module is also responsible for controlling the sensorless operation module to run in speed mode or position mode after receiving instructions from the main control.

[0104] Sensorless operation module: The speed sensorless operation module uses the real-time speed identification operation mode, including position control module, speed control module, and angle control module. The position control module includes position loop control, which comes from the position command of the master control and the position feedback of the speed position identification module. The speed control module performs PI control through the speed command and the feedback of the speed position identification module, and gives instructions to the current module. The angle control module includes an open-loop startup control submodule and a closed-loop operation control submodule.

[0105] If the sensorless operation mode is used during operation, it can be directly switched to the closed-loop operation control submodule. Based on the identified speed, the motor angle is identified by integrating the speed, and then the current blade angle (i.e. the predicted blade position) is obtained by accumulating the blade angle before the sensorless operation mode. If the sensorless operation mode is used for startup, the open-loop startup control module is entered. If the blade angle is credible before startup, the angle is accumulated; if the blade angle is unreliable, the accumulation starts from 0. The open-loop startup control module enters the closed-loop operation control module through positioning, open-loop startup and open-loop conversion. Positioning is to position the rotor through a fixed current, and then an open-loop starting current is applied to rotate the rotor. The speed identification module synchronously identifies the speed, and after reaching the closed-loop threshold, it switches to the closed-loop rotation mode for operation.

[0106] The angle control module is used to determine the predicted blade position, and then based on the predicted blade position and the retraction instruction, determine whether to use the position control module and the speed control module for control, or to use the speed control module for control to complete the retraction.

[0107] In this embodiment, in the normal operating mode, if the position sensor produces an angle slip or a sudden change in speed, the identification data can be combined to determine that the position sensor has a fault through data comparison; if it is determined that a fault has occurred, it can be switched to a speedless mode (i.e., a sensorless operation mode) to ensure the safety of the blades. If the position sensor of the wind turbine blade motor fails during normal operation (it may be a position sensor wiring failure, position sensor signal parsing error, etc.), it can be directly switched to a speed sensorless operation mode without sensing, and the load can be quickly reduced and the blades can be retracted. After switching to the sensorless operation mode and retracting the blades under a position sensor failure, if the position sensor failure is restored during the retracting process or after the blades are in place, the actual blade position can be calibrated by walking the blades to the proximity switch position, reducing the process of personnel climbing the tower. When the variable pitch operation is performed under a position sensor failure, the operation of the motor can be prevented from getting stuck by starting the speed sensorless operation scheme through an open loop.

[0108] In order to execute the corresponding steps in the above embodiments and various possible methods, a method for implementing a position sensor fault processing device 200 is provided below. Optionally, the position sensor fault processing device 200 may adopt the above Figure 1The device structure of the electronic device 100 is shown. Fig.10 , Fig.10 The block diagram of the position sensor fault processing device 200 provided in the embodiment of the present application. It should be noted that the basic principle and technical effect of the position sensor fault processing device 200 provided in the present embodiment are the same as those of the above embodiment. For the sake of brief description, the parts not mentioned in the present embodiment can refer to the corresponding contents in the above embodiment. The position sensor fault processing device 200 may include: a result acquisition module 210 and a processing module 220.

[0109] The result obtaining module 210 is used to obtain a fault detection result, wherein the fault detection result is used to indicate whether the position sensor is faulty.

[0110] The processing module 220 is configured to obtain a predicted motor speed by using a speed observer when the fault detection result indicates that the position sensor is faulty.

[0111] The processing module 220 is further configured to obtain a predicted motor position according to the predicted motor speed.

[0112] The processing module 220 is further configured to obtain a predicted propeller blade position according to the predicted motor position, and to control the motor according to the propeller return instruction, the predicted motor speed corresponding to the predicted motor position, and the predicted propeller blade position, so that the predicted propeller blade position reaches a preset position. The motor continues to operate during the process of controlling the motor to make the predicted propeller blade position reach the preset position.

[0113] In this embodiment, the processing module 220 can also be used to: when the position sensor recovers from a fault to a fault-free state, control the motor so that the blade passes through the second target switch; when it is determined that the blade passes through the second target switch, based on the saved correspondence between different switches and different third blade positions, determine the third blade position corresponding to the second target switch, and update the current blade position according to the third blade position corresponding to the second target switch, wherein the current predicted blade position is the current blade position, wherein the third blade position corresponding to different switches is obtained by a fault-free position sensor, and the second target switch is one of the different switches.

[0114] Optionally, the above modules can be stored in the form of software or firmware. Figure 1 The memory 110 shown in the figure may be fixed in the operating system (OS) of the electronic device 100 and may be Figure 1Meanwhile, the data and program codes required for executing the above modules may be stored in the memory 110.

[0115] An embodiment of the present application further provides a readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the position sensor fault processing method is implemented.

[0116] In summary, the embodiments of the present application provide a position sensor fault handling method and related devices, firstly obtaining a fault detection result, the fault detection result is used to indicate whether the position sensor used to obtain the motor position in the wind turbine pitch control system is faulty; when the fault detection result indicates that the position sensor is faulty, the speed observer is used to obtain the motor predicted speed; the motor predicted position is obtained according to the motor predicted speed, and then the blade predicted position is obtained according to the motor predicted position, and the motor is controlled according to the retraction instruction, the motor predicted speed corresponding to the motor predicted position, and the blade predicted position, so that the blade predicted position reaches the preset position. Among them, the motor continues to run in the process of controlling the motor to make the blade predicted position reach the preset position. In this way, when it is determined that the position sensor is faulty, the retraction can be completed without stopping and restarting, which has the characteristics of fast and efficient.

[0117] In several embodiments provided in the present application, it should be understood that the disclosed devices and methods can also be implemented in other ways. The device embodiments described above are merely schematic. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the devices, methods and computer program products according to multiple embodiments of the present application. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of a code, and the module, a program segment or a part of a code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or action, or can be implemented with a combination of dedicated hardware and computer instructions.

[0118] In addition, the functional modules in the various embodiments of the present application may be integrated together to form an independent part, or each module may exist separately, or two or more modules may be integrated to form an independent part.

[0119] If the functions are implemented in the form of software function modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium, including several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0120] The above description is only an optional embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for handling position sensor failure, characterized in that: The method comprises: Obtaining a fault detection result, wherein the fault detection result is used to indicate whether the position sensor is faulty; When the fault detection result indicates that the position sensor is faulty, using a speed observer to obtain a predicted motor speed; Obtaining a predicted position of the motor according to the predicted speed of the motor; The predicted blade position is obtained based on the predicted motor position, and the motor is controlled based on the retraction instruction, the predicted motor speed corresponding to the predicted motor position, and the predicted blade position, so that the predicted blade position reaches a preset position, wherein the motor continues to run during the process of controlling the motor to make the predicted blade position reach the preset position.

2. The method according to claim 1, characterized in that The method of obtaining the predicted blade position according to the predicted motor position, and controlling the motor according to the propeller return instruction, the predicted motor speed corresponding to the predicted motor position, and the predicted blade position, so that the predicted blade position reaches a preset position, includes: If the fault detection result indicates that the position sensor is faulty during startup, the motor is started in an open loop, and the predicted position of the blade is obtained according to the predicted position of the motor during the open loop startup of the motor; When the obtained predicted motor speed is greater than or equal to the preset speed, the motor is controlled according to the retraction instruction, the obtained predicted motor speed, the predicted motor position and the predicted blade position so that the predicted blade position reaches the preset position.

3. The method according to claim 2, characterized in that The step of obtaining the predicted position of the blade according to the predicted position of the motor during the open-loop starting process of the motor includes: If the first propeller blade position before starting is credible, obtaining the propeller blade predicted position according to the first propeller blade position and the motor predicted position obtained during the motor open-loop starting process; If the first propeller position before starting is not feasible, the propeller predicted position is obtained based on the motor predicted position obtained during the motor open-loop starting process, taking 0 as the starting point.

4. The method according to claim 1, characterized in that: The method of obtaining the predicted blade position according to the predicted motor position, and controlling the motor according to the propeller return instruction, the predicted motor speed corresponding to the predicted motor position, and the predicted blade position, so that the predicted blade position reaches a preset position, includes: If the fault detection result indicates that the position sensor is faulty during operation, taking the second blade position before the position sensor fails as a starting point, obtaining the blade predicted position according to the motor predicted position; According to the retraction instruction, the obtained motor predicted speed, the motor predicted position and the blade predicted position, the motor is controlled so that the blade predicted position reaches a preset position.

5. The method according to any one of claims 1 to 4, characterized in that: The method of obtaining the predicted blade position according to the predicted motor position, and controlling the motor according to the propeller return instruction, the predicted motor speed corresponding to the predicted motor position, and the predicted blade position, so that the predicted blade position reaches a preset position, includes: During the control process, when it is determined that the paddle reaches the first target switch, the third paddle position corresponding to the first target switch is obtained based on the saved correspondence between different switches and different third paddle positions, wherein the third paddle position corresponding to the different switches is obtained by a fault-free position sensor, and the first target switch is one of the different switches; The current predicted blade position is updated according to the third blade position corresponding to the first target switch.

6. The method according to any one of claims 1 to 4, characterized in that: The method further comprises: When the position sensor recovers from a fault, the motor is controlled to make the blade pass through a second target switch; When it is determined that the blade passes through the second target switch, the third blade position corresponding to the second target switch is determined based on the saved correspondence between different switches and different third blade positions, and the current blade position is updated according to the third blade position corresponding to the second target switch, wherein the current predicted blade position is the current blade position, wherein the third blade position corresponding to different switches is obtained by a fault-free position sensor, and the second target switch is one of the different switches.

7. The method according to any one of claims 1 to 4, characterized in that: The obtaining of the fault detection result comprises: According to a first preset period, periodically obtaining a predicted motor speed and a predicted motor position; According to a second preset period, periodically calculating a speed difference between a current motor predicted speed and a motor reference speed, and a position difference between a current motor predicted position and a motor reference position, and determining whether the speed difference is greater than a preset speed difference, and whether the position difference is greater than a preset position difference, wherein the motor reference speed and the motor reference position are obtained by the position sensor, and the second preset period is greater than the first preset period; If the speed difference is greater than the preset speed difference and the position difference is greater than the preset position difference, it is determined that the position sensor is faulty.

8. The method according to any one of claims 1 to 4, characterized in that: The method further comprises: Obtaining a jump detection result of a current control signal of the motor, wherein the jump detection result is used to indicate whether the current control signal jumps abnormally; When the fault detection result indicates that the position sensor is faulty and the jump detection result indicates that the current control signal jumps abnormally, the steps of obtaining the predicted blade position based on the predicted motor position, and controlling the motor based on the retraction instruction, the predicted motor speed corresponding to the predicted motor position, and the predicted blade position are performed to make the predicted blade position reach a preset position.

9. A position sensor fault processing device, characterized in that: The device comprises: A result obtaining module, used to obtain a fault detection result, wherein the fault detection result is used to indicate whether the position sensor is faulty; A processing module, configured to obtain a predicted motor speed by using a speed observer when the fault detection result indicates that the position sensor is faulty; The processing module is further used to obtain a predicted position of the motor according to the predicted speed of the motor; The processing module is also used to obtain the predicted blade position based on the predicted motor position, and control the motor according to the retraction instruction, the predicted motor speed corresponding to the predicted motor position, and the predicted blade position, so that the predicted blade position reaches a preset position, wherein the motor continues to run during the process of controlling the motor to make the predicted blade position reach the preset position.

10. An electronic device, characterized in that: It comprises a processor and a memory, wherein the memory stores machine executable instructions that can be executed by the processor, and the processor can execute the machine executable instructions to implement the position sensor fault processing method described in any one of claims 1-8.

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