A Method for Judging and Handling Communication Faults in a Wind Turbine Pitch Control System

Abstract

The present invention discloses a method for judging and handling communication faults in a variable pitch control system of a fan. The heartbeat signal agreed upon by the variable pitch system and the main control system through the communication protocol is detected. If the heartbeat signal does not change within the preset time, it is judged that a communication fault occurs, and an emergency pitch reduction operation is executed. The present invention reliably ensures to avoid or reduce the influence of communication delay and communication interference on the heartbeat signal, improves the control accuracy of judging communication faults in the variable pitch control system of the fan, and improves the safety of the variable pitch control system of the fan.

Description

Technical Field

[0001] The present invention belongs to the field of pitch control systems in the wind power generation industry, and particularly relates to a method for judging and handling communication faults in a wind turbine pitch control system. Background Art

[0002] In the wind power generation industry, in order to monitor the communication status between the pitch system and the main control system, the prior art usually uses a pitch control system to detect the status of the communication driver program state machine. If the status is abnormal, it is determined that a communication fault occurs, and then an emergency pitch-down logic is executed. However, due to the relatively harsh communication environment of wind turbines, slip rings, vibrations, temperature, and electromagnetic interference will all affect the communication quality. Therefore, using the existing solution to judge the status of the communication state machine is prone to false alarms of communication faults.

[0003] Therefore, the applicant hopes to seek a technical solution to improve the above technical problems. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to propose a method for judging and handling communication faults in a wind turbine pitch control system, which reliably ensures that the heartbeat signal is avoided or reduced from being affected by communication delay and communication interference, improves the control accuracy of judging communication faults in the wind turbine pitch control system, and improves the safety of the wind turbine pitch control system.

[0005] Therefore, the technical solution adopted by the present invention is as follows:

[0006] A method for judging and handling communication faults in a wind turbine pitch control system, which detects a heartbeat signal agreed upon by the pitch system and the main control system through a communication protocol. If the heartbeat signal does not change within a preset time, it is determined that a communication fault occurs, and an emergency pitch-down operation is executed.

[0007] Preferably, the main control system sends a heartbeat signal A to the pitch system through a communication protocol. The pitch system periodically detects whether the heartbeat signal A will change. If the heartbeat signal A does not change within a preset time, it is determined that a communication fault occurs, and an emergency pitch-down operation is executed; the pitch system sends a heartbeat signal B to the main control system through a communication protocol. The main control system periodically detects whether the heartbeat signal B will change. If the heartbeat signal B does not change within a preset time, it is determined that a communication fault occurs, and an emergency pitch-down operation is executed.

[0008] Preferably, the heartbeat signal A is generated by the main control system through an autonomous heartbeat logic; the heartbeat signal B is generated by the pitch system through an autonomous heartbeat logic.

[0009] Preferably, when the pitch system periodically detects whether the heartbeat signal A will change, the time when the heartbeat signal A does not change is timed as the heartbeat time. When it is found that the heartbeat time exceeds the preset time, a communication failure is judged, and an emergency pitch-down operation is performed.

[0010] Preferably, the pitch system times the time when the heartbeat signal A does not change through a timer; and / or the sampling frequency of the pitch system is at least greater than twice the frequency of the heartbeat signal A.

[0011] Preferably, the program code of the heartbeat signal A includes:

[0012]

[0013]

[0014] Preferably, when the master control system periodically detects whether the heartbeat signal B will change, the time when the heartbeat signal B does not change is timed as the heartbeat time. When it is found that the heartbeat time exceeds the preset time, a communication failure is judged, and an emergency pitch-down operation is performed.

[0015] Preferably, the master control system times the time when the heartbeat signal B does not change through a timer; and / or the sampling frequency of the master control system is at least greater than twice the frequency of the heartbeat signal B.

[0016] Preferably, the sampling period of the master control system is 10 - 30 ms.

[0017] Preferably, the program code of the heartbeat signal B includes:

[0018]

[0019] On the one hand, the present invention sends a heartbeat signal from the master control system to the pitch system to detect whether the heartbeat signal changes within a preset time; on the other hand, the pitch system also sends a heartbeat signal of autonomous logic control to the master control system to detect whether the heartbeat signal changes within a preset time; if any one of the heartbeat signals does not change within the preset time, a communication failure is judged, and an emergency pitch-down operation is performed; the present invention reliably guarantees to avoid or reduce the influence of communication delay and communication interference on the heartbeat signal, improves the control accuracy of communication failure judgment in the fan pitch control system, and improves the safety of the fan pitch control system. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic diagram of communication failure judgment and processing logic in the fan pitch control system under the specific embodiment of the present application;

[0021] Figure 2It is a schematic diagram of the specific control logic process of the heartbeat signal A under the specific implementation mode of this application;

[0022] Figure 3 It is a schematic diagram of the autonomous heartbeat logic process of the pitch system generating the heartbeat signal B under the specific implementation mode of this application. Specific implementation mode

[0023] The embodiment of the present invention discloses a method for judging and handling communication faults in a wind turbine pitch control system. It detects the heartbeat signal agreed upon by the pitch system and the main control system through a communication protocol. If the heartbeat signal does not change within a preset time, it is determined that a communication fault has occurred, and an emergency pitch-down operation is performed.

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0025] A method for judging and handling communication faults in a wind turbine pitch control system. When the pitch system is operating normally, it detects the heartbeat signal agreed upon by the pitch system and the main control system through a communication protocol. If the heartbeat signal does not change within a preset time, it is determined that a communication fault has occurred, and an emergency pitch-down operation is performed, and the blade returns to the storm position; for the specific control flow logic, please refer to Figure 1 as shown;

[0026] Preferably, in this embodiment, the main control system sends the heartbeat signal A to the pitch system through the communication protocol. The pitch system periodically detects whether the heartbeat signal A will change. If the heartbeat signal A does not change within a preset time, it is determined that a communication fault has occurred, and an emergency pitch-down operation is performed; the pitch system sends the heartbeat signal B to the main control system through the communication protocol. The main control system periodically detects whether the heartbeat signal B will change. If the heartbeat signal B does not change within a preset time, it is determined that a communication fault has occurred, and an emergency pitch-down operation is performed.

[0027] Preferably, in this embodiment, the heartbeat signal A is generated by the main control system through an autonomous heartbeat logic; the heartbeat signal B is generated by the pitch system through an autonomous heartbeat logic (please refer specifically to Figure 3 as shown).

[0028] Preferably, in this embodiment, when the pitch system periodically detects whether the heartbeat signal A will change, the time when the heartbeat signal A does not change is timed as the heartbeat time ( Figure 2displayed as "timer accumulation"), when it is found that the heartbeat time exceeds the preset time, it is determined that there is a communication failure, and an emergency blade retraction operation is performed. Further preferably, the pitch system measures the time when the heartbeat signal A does not change through a timer; according to the Nyquist sampling theorem, in order to ensure accurate sampling, the sampling frequency usually needs to be greater than twice the highest signal frequency. The pitch heartbeat signal frequency needs to be coordinated with the sampling frequency. Preferably, in this embodiment, the sampling frequency of the pitch system is at least greater than twice the frequency of the heartbeat signal A; for the specific control logic of the heartbeat signal A in this embodiment, please refer to Figure 2 as shown.

[0029] Specifically preferably, in this embodiment, the program code of the heartbeat signal A (i.e., the main control heartbeat signal) includes:

[0030]

[0031]

[0032] The code determines the main control heartbeat signal. If the main control heartbeat signal does not change, the timing starts. If the heartbeat time exceeds the preset time, it is determined that the heartbeat is abnormal. After the pitch system detects this heartbeat abnormality, it executes the emergency blade retraction operation logic.

[0033] It should be noted that, in this embodiment, the communication quality can also be judged by the magnitude of the heartbeat time. The longer the time, the worse the communication quality; the heartbeat time is convenient for intuitively judging the communication state between the main control system and the pitch system at this time.

[0034] Preferably, in this embodiment, when the main control system periodically detects whether the heartbeat signal B will change, the time when the heartbeat signal B does not change is measured as the heartbeat time. When it is found that the heartbeat time exceeds the preset time, it is determined that there is a communication failure, and an emergency blade retraction operation is performed; further preferably, the main control system measures the time when the heartbeat signal B does not change through a timer; similarly to the heartbeat signal A, according to the Nyquist sampling theorem, in order to ensure accurate sampling, the sampling frequency usually needs to be greater than twice the highest signal frequency. The pitch heartbeat signal frequency needs to be coordinated with the sampling frequency. Preferably, in this embodiment, the sampling frequency of the main control system is at least greater than twice the frequency of the heartbeat signal B; preferably, in this embodiment, the sampling period of the main control system is 10 - 30 ms;

[0035] Specifically preferably, in this embodiment, the main control system judges the heartbeat signal B (i.e., the pitch heartbeat signal) sent by the pitch system at a cycle of 20 ms. If there is no change for 8 consecutive cycles, a communication pulse detection failure of the pitch system will be reported; the minimum period of the pitch autonomous heartbeat signal (heartbeat signal B) should be 40 ms. To ensure sampling stability, in this embodiment, the period of the pitch system autonomous heartbeat signal is set to 60 ms.

[0036] Specifically preferably, in this embodiment, the program code of the heartbeat signal B includes:

[0037]

[0038]

[0039] Among them, PitchHeartBeat in the code is the heartbeat bit, the set value of HEART_BEAT_TOGGLE is 30, and intervall is the task period of 1. The above code can generate an autonomous heartbeat signal with a period of 60 ms.

[0040] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claimed rights.

[0041] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for judging and handling communication faults in a variable pitch control system of a fan, characterized in that Detect the heartbeat signal agreed upon by the pitch system and the main control system through the communication protocol. If the heartbeat signal does not change within the preset time, it is determined that there is a communication failure, and an emergency pitch retraction operation is performed; The main control system sends heartbeat signal A to the pitch system through the communication protocol. The pitch system periodically detects whether the heartbeat signal A will change. If the heartbeat signal A does not change within the preset time, it is determined that there is a communication failure, and an emergency pitch retraction operation is performed; The pitch system sends heartbeat signal B to the main control system through the communication protocol. The main control system periodically detects whether the heartbeat signal B will change. If the heartbeat signal B does not change within the preset time, it is determined that there is a communication failure, and an emergency pitch retraction operation is performed; The heartbeat signal A is generated by the main control system through an independent heartbeat logic; The heartbeat signal B is generated by the pitch system through an independent heartbeat logic; The sampling frequency of the pitch system is at least greater than twice the frequency of the heartbeat signal A; The sampling frequency of the main control system is at least greater than twice the frequency of the heartbeat signal B.

2. The communication fault judgment and handling method in the wind turbine pitch control system according to claim 1, characterized in that When the pitch system periodically detects whether the heartbeat signal A will change, the time when the heartbeat signal A does not change is timed as the heartbeat time. When it is found that the heartbeat time exceeds the preset time, it is determined that there is a communication failure, and an emergency pitch retraction operation is performed.

3. The communication fault judgment and processing method in the wind turbine pitch control system according to claim 2, characterized in that, The pitch system uses a timer to time the time when the heartbeat signal A does not change.

4. The communication fault judgment and handling method in the fan pitch control system according to claim 2, characterized in that The program code of the heartbeat signal A includes: if( HeartBeat_value == (commands.CtrlWord1PitchSystem & CTRL_1_HEARTBEAT)) / / Determine the main control heartbeat signal HeartBeat_timer += intervall; / / Heartbeat time else { HeartBeat_timer = 0; / / Clear the heartbeat time HeartBeat_OK = true; / / Heartbeat normal HeartBeat_value = (commands.CtrlWord1PitchSystem & CTRL_1_HEARTBEAT); } if( HeartBeat_timer >= *wprm_conf_CommunicationTimeout.pValue ) / / Heartbeat time out { HeartBeat_timer = 0; HeartBeat_OK = false; / / Heartbeat abnormal HeartBeat_value = (commands.CtrlWord1PitchSystem & CTRL_1_HEARTBEAT); }。 5. The communication fault judgment and processing method in the wind turbine pitch control system according to claim 1, characterized in that When the main control system periodically detects whether the heartbeat signal B will change, the time when the heartbeat signal B does not change is timed as the heartbeat time. When it is found that the heartbeat time exceeds the preset time, it is determined that there is a communication failure, and an emergency pitch retraction operation is performed.

6. The method for judging and handling communication faults in the wind turbine pitch control system according to claim 5, wherein The master control system measures the time during which the heartbeat signal B does not change through a timer.

7. The method for judging and handling communication faults in the wind turbine pitch control system according to claim 6, wherein The sampling period of the master control system is 10 - 30 ms.

8. The communication fault judgment and handling method in the fan pitch control system according to claim 5, characterized in that, The program code of the heartbeat signal B includes: if (Pitch_HeartBeat_timer <= HEART_BEAT_TOGGLE) { PitchHeartBeat = true; / / Pitch heartbeat Pitch_HeartBeat_timer += intervall; } else { if(Pitch_HeartBeat_timer >= HEART_BEAT_TOGGLE * 2) { Pitch_HeartBeat_timer = 0; PitchHeartBeat = true; } else { c += intervall; PitchHeartBeat = false; } }。

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