阅读说明：本技术 基于状态机的变桨系统控制方法、变桨系统以及状态机 (Variable pitch system control method based on state machine, variable pitch system and state machine ) 是由 谢峥 张勋 张利军 崔晓光 位俊雷 李刚 杨东军 林祥礼 赵栋 夏常凯 狄振锋 于 2020-06-29 设计创作，主要内容包括：本发明提供的基于状态机的变桨系统控制方法,应用于变桨系统的状态机,所述控制方法包括：确定所述变桨系统的多个状态机模式,所述状态机模式包括：待机模式、正常工作模式、紧急闭环模式以及紧急开环模式；当所述变桨系统处于任一所述状态机模式下,判断所述变桨系统是否满足状态模式切换条件,若满足,则控制不同所述状态机模式进行切换。该发明基于状态机界定变桨系统的状态机模式,通过变桨系统控制不同状态机模式之间的切换,保证了风电发电机组的安全可靠地运行,简化了逻辑,减少了空间内存的占用,降低了变桨系统的动作响应时间。(The invention provides a variable pitch system control method based on a state machine, which is applied to the state machine of a variable pitch system, and comprises the following steps: determining a plurality of state machine modes of the pitch system, the state machine modes comprising: a standby mode, a normal operating mode, an emergency closed-loop mode and an emergency open-loop mode; and when the variable pitch system is in any one state machine mode, judging whether the variable pitch system meets the state mode switching condition, and if so, controlling different state machine modes to switch. According to the invention, the state machine mode of the pitch system is defined based on the state machine, and the switching between different state machine modes is controlled by the pitch system, so that the safe and reliable operation of the wind power generator set is ensured, the logic is simplified, the occupation of space memory is reduced, and the action response time of the pitch system is reduced.)

1. A control method of a variable pitch system based on a state machine is applied to the state machine of the variable pitch system, the variable pitch system comprises a controller, three axle boxes, a driver, a motor, an encoder, a first limit switch and a second limit switch, the driver, the motor, the encoder, the first limit switch and the second limit switch are connected with each axle box, the first limit switch and the second limit switch are redundant, and the control method is characterized by comprising the following steps:

determining a plurality of state machine modes of the pitch system, the state machine modes comprising: a standby mode, a normal operating mode, an emergency closed-loop mode and an emergency open-loop mode;

and when the variable pitch system is in any one state machine mode, judging whether the variable pitch system meets the state mode switching condition, and if so, controlling different state machine modes to switch.

2. The state-machine based pitch system control method of claim 1, wherein the state-machine mode further comprises: a manual mode of operation.

3. The state-machine based pitch system control method of claim 1, wherein the pitch system switches the plurality of state-machine modes according to the following steps:

when the variable pitch system is in the standby mode, if a control instruction of the controller is received, switching to the normal working mode; switching to the emergency closed-loop mode if a first fault is detected, wherein the first fault comprises a non-encoder fault;

when the variable pitch system is in the normal working mode, if the first fault is detected, switching to the emergency closed-loop mode; if a second fault is detected, switching to the emergency open-loop mode, wherein the second fault comprises an encoder fault; if the control instruction is not received, switching to the standby mode;

when the variable pitch system is in the emergency closed-loop mode, if the second fault is detected, switching to the emergency open-loop mode; if the first fault is eliminated and the control instruction is received, switching to the normal working mode; if the first fault is eliminated and the control instruction is not received, switching to the standby mode;

and when the variable pitch system is in the emergency open loop mode, if the second fault is eliminated and the control instruction is received, switching to the normal working mode.

4. The state-machine based pitch system control method of claim 3, wherein if the pitch system is in the standby mode, the normal operating mode, the emergency closed-loop mode, or the emergency open-loop mode, if the pitch system is engaged with a hand-operated box, then switching to a manual operation mode.

5. The state-machine based pitch system control method of claim 4, wherein the switching method when the pitch system is in the standby mode comprises:

judging whether the variable pitch system is powered on or not, if so, judging whether the variable pitch system is initialized or not, if so, judging whether the variable pitch system is self-checked or not, if so, judging that the variable pitch system is in a standby mode, and judging whether the variable pitch system is connected to the manual operation box or not;

if the manual operation box is accessed, switching to the manual operation mode, otherwise, judging whether the variable pitch system receives the control instruction;

if the control instruction is received, switching to the normal working mode, and controlling the driver to drive the motor to move by the controller, otherwise, judging whether the variable pitch system detects the first fault;

if the first fault is detected, switching to the emergency closed-loop mode, and controlling the driver to drive the motor to move to a first target position by the controller; and if not, returning to judge whether the variable pitch system is connected to the manual operation box.

6. The state-machine based pitch system control method of claim 5, wherein the switching method when the pitch system is in the normal operating mode comprises:

when the variable pitch system is in the normal working mode, the controller gives a target position and a target speed, the controller controls the driver to drive the motor to move to the target position according to the target speed, and whether the variable pitch system is connected to the manual operation box or not is judged;

if the manual operation box is connected, switching to the manual operation mode, otherwise, judging whether the variable pitch system detects the first fault;

if the first fault is detected, switching to the emergency closed-loop mode, and controlling the driver to drive the motor to move to the first target position by the controller; otherwise, judging whether the variable pitch system detects the second fault;

if the second fault is detected, switching to the emergency open-loop mode, and controlling the driver to drive the motor to move feathering by the controller until the paddle touches the first limit switch to reach a second target position or touches the second limit switch to reach a third target position; otherwise, judging whether the variable pitch system receives the control instruction;

if the control instruction is not received, switching to the standby mode, controlling the driver to drive the motor to perform deceleration movement by the controller until the motor stops moving, and performing band-type braking by the motor, otherwise, controlling the driver to drive the motor to perform movement by the variable pitch system according to the control instruction, and returning to judge whether the variable pitch system is connected to the manual operation box.

7. The state-machine based pitch system control method of claim 6, wherein the switching method when the pitch system is in the emergency closed-loop mode comprises:

when the variable pitch system is in the emergency closed-loop mode, the controller controls the driver to drive the motor to move to the first target position, and whether the variable pitch system is connected to the manual operation box is judged;

if the manual operation box is connected, switching to the manual operation mode, otherwise, judging whether the variable pitch system detects the second fault;

if the second fault is detected, switching to the emergency open-loop mode, and controlling the driver to drive the motor to move feathering by the controller until the blades reach the second target position or the third target position; otherwise, judging whether the variable pitch system eliminates the first fault;

if the first fault is eliminated and the control instruction is received, switching to the normal working mode, and controlling the driver to drive the motor to move to the target position according to the target speed by the controller; if the first fault is eliminated and the control instruction is not received, switching to the standby mode, otherwise, returning to judge whether the variable pitch system is connected to the manual operation box.

8. The state-machine based pitch system control method of claim 7, wherein the switching method when the pitch system is in the emergency open-loop mode comprises:

when the variable pitch system is in the emergency open-loop mode, the controller controls the driver to drive the motor to feather towards the second target position, if the first limit switch fails, the controller controls the driver to drive the motor to feather towards the third target position, and whether the variable pitch system is connected to the manual operation box or not is judged;

if the manual operation box is connected, switching to the manual operation mode, otherwise, judging whether the second fault is eliminated by the variable pitch system;

if the second fault is eliminated and the control instruction is received, switching to the normal working mode, and controlling the driver to drive the motor to move to the target position according to the target speed by the controller; and otherwise, returning to judge whether the variable pitch system is connected to the manual operation box.

9. A pitch system comprising a state machine for performing the method of any one of claims 1 to 8.

10. A state machine for use in a pitch system, comprising:

determining a plurality of state machine modes of the pitch system, the state machine modes comprising: a standby mode, a normal operating mode, an emergency closed-loop mode and an emergency open-loop mode;

and when the variable pitch system is in any one state machine mode, judging whether the variable pitch system meets the state mode switching condition, and if so, controlling different state machine modes to switch.

Technical Field

The invention relates to the technical field of locomotive brake control, in particular to a variable pitch system control method based on a state machine, a variable pitch system and the state machine.

Background

In a wind power generation system, a pitch system is an important component of a wind generating set, and the pitch system changes the attack angle of airflow to blades by adjusting the pitch angle of the blades so as to control the pneumatic torque and the pneumatic power captured by a wind wheel.

The existing pitch system control method controls the fan generator set to work in sequence according to the working process of the fan generator set, and the wind power generator set can run safely and reliably.

However, in the prior art, the control method of the pitch system is complex in logic and large in occupied space and memory, and once the pitch system fails, potential safety hazards are brought by misoperation of the pitch system.

Disclosure of Invention

In order to solve the technical problems of complex logic, large occupied space memory and low safety of a pitch system control method in the prior art, the invention provides a state machine-based pitch system control method.

The invention provides a variable pitch system control method based on a state machine, which is applied to the state machine of a variable pitch system, wherein the variable pitch system comprises a controller, three axle boxes, a driver, a motor, an encoder, a first limit switch and a second limit switch, wherein the driver, the motor, the encoder, the first limit switch and the second limit switch are connected with each axle box, and the first limit switch and the second limit switch are redundant with each other, and the control method is characterized by comprising the following steps:

determining a plurality of state machine modes of the pitch system, the state machine modes comprising: a standby mode, a normal operating mode, an emergency closed-loop mode and an emergency open-loop mode;

and when the variable pitch system is in any one state machine mode, judging whether the variable pitch system meets the state mode switching condition, and if so, controlling different state machine modes to switch.

Further, the state machine mode further comprises: a manual mode of operation.

Further, the pitch system switches the plurality of state machine modes according to the following steps:

when the variable pitch system is in the standby mode, if a control instruction of the controller is received, switching to the normal working mode; switching to the emergency closed-loop mode if a first fault is detected, wherein the first fault comprises a non-encoder fault;

when the variable pitch system is in the normal working mode, if the first fault is detected, switching to the emergency closed-loop mode; if a second fault is detected, switching to the emergency open-loop mode, wherein the second fault comprises an encoder fault; if the control instruction is not received, switching to the standby mode;

when the variable pitch system is in the emergency closed-loop mode, if the second fault is detected, switching to the emergency open-loop mode; if the first fault is eliminated and the control instruction is received, switching to the normal working mode; if the first fault is eliminated and the control instruction is not received, switching to the standby mode;

and when the variable pitch system is in the emergency open loop mode, if the second fault is eliminated and the control instruction is received, switching to the normal working mode.

Further, if the variable pitch system is in the standby mode, the normal working mode, the emergency closed-loop mode or the emergency open-loop mode, if the variable pitch system is connected to the manual operation box, the variable pitch system is switched to a manual operation mode.

Further, the switching method of the pitch system in the standby mode comprises the following steps:

the switching method when the variable pitch system is in the standby mode comprises the following steps:

judging whether the variable pitch system is powered on or not, if so, judging whether the variable pitch system is initialized or not, if so, judging whether the variable pitch system is self-checked or not, if so, judging that the variable pitch system is in a standby mode, and judging whether the variable pitch system is connected to the manual operation box or not;

if the manual operation box is accessed, switching to the manual operation mode, otherwise, judging whether the variable pitch system receives the control instruction;

if the control instruction is received, switching to the normal working mode, and controlling the driver to drive the motor to move by the controller, otherwise, judging whether the variable pitch system detects the first fault;

if the first fault is detected, switching to the emergency closed-loop mode, and controlling the driver to drive the motor to move to a first target position by the controller; and if not, returning to judge whether the variable pitch system is connected to the manual operation box.

Further, the switching method of the pitch system in the normal working mode comprises the following steps:

the switching method of the variable pitch system in the normal working mode comprises the following steps:

when the variable pitch system is in the normal working mode, the controller gives a target position and a target speed, the controller controls the driver to drive the motor to move to the target position according to the target speed, and whether the variable pitch system is connected to the manual operation box or not is judged;

if the manual operation box is connected, switching to the manual operation mode, otherwise, judging whether the variable pitch system detects the first fault;

if the first fault is detected, switching to the emergency closed-loop mode, and controlling the driver to drive the motor to move to the first target position by the controller; otherwise, judging whether the variable pitch system detects the second fault;

if the second fault is detected, switching to the emergency open-loop mode, and controlling the driver to drive the motor to move feathering by the controller until the paddle touches the first limit switch to reach a second target position or touches the second limit switch to reach a third target position; otherwise, judging whether the variable pitch system receives the control instruction;

if the control instruction is not received, switching to the standby mode, controlling the driver to drive the motor to perform deceleration movement by the controller until the motor stops moving, and performing band-type braking by the motor, otherwise, controlling the driver to drive the motor to perform movement by the variable pitch system according to the control instruction, and returning to judge whether the variable pitch system is connected to the manual operation box.

Further, the switching method when the pitch system is in the emergency closed loop mode comprises the following steps:

when the variable pitch system is in the emergency closed-loop mode, the controller controls the driver to drive the motor to move to the first target position, and whether the variable pitch system is connected to the manual operation box is judged;

if the manual operation box is connected, switching to the manual operation mode, otherwise, judging whether the variable pitch system detects the second fault;

if the second fault is detected, switching to the emergency open-loop mode, and controlling the driver to drive the motor to move feathering by the controller until the blades reach the second target position or the third target position; otherwise, judging whether the variable pitch system eliminates the first fault;

if the first fault is eliminated and the control instruction is received, switching to the normal working mode, and controlling the driver to drive the motor to move to the target position according to the target speed by the controller; if the first fault is eliminated and the control instruction is not received, switching to the standby mode, otherwise, returning to judge whether the variable pitch system is connected to the manual operation box.

Further, the switching method when the pitch system is in the emergency open loop mode comprises the following steps:

when the variable pitch system is in the emergency open-loop mode, the controller controls the driver to drive the motor to feather towards the second target position, if the first limit switch fails, the controller controls the driver to drive the motor to feather towards the third target position, and whether the variable pitch system is connected to the manual operation box or not is judged;

if the manual operation box is connected, switching to the manual operation mode, otherwise, judging whether the second fault is eliminated by the variable pitch system;

if the second fault is eliminated and the control instruction is received, switching to the normal working mode, and controlling the driver to drive the motor to move to the target position according to the target speed by the controller; and otherwise, returning to judge whether the variable pitch system is connected to the manual operation box.

The invention also provides a pitch system comprising a state machine for performing the method as described above.

The invention also provides a state machine applied to the variable pitch system, which comprises:

determining a plurality of state machine modes of the pitch system, the state machine modes comprising: a standby mode, a normal operating mode, an emergency closed-loop mode and an emergency open-loop mode;

and when the variable pitch system is in any one state machine mode, judging whether the variable pitch system meets the state mode switching condition, and if so, controlling different state machine modes to switch.

The invention has the technical effects or advantages that:

(1) the variable pitch system control method based on the state machine provided by the invention determines a plurality of state machine modes of the variable pitch system, and controls different state machine modes to switch according to state mode switching conditions. According to the method, the state machine mode of the pitch system is defined based on the state machine, and the switching between different state machine modes is controlled through the pitch system, so that the safe and reliable operation of the wind power generator set is ensured, the logic is simplified, the occupation of space memory is reduced, and the action response time of the pitch system is reduced.

(2) According to the variable pitch system control method based on the state machine, the state machine modes further comprise the manual operation mode, the priority of the manual operation mode is higher than that of other state machine modes, the safety performance is higher, the other state machine modes can be switched to the manual operation mode, and the safe and reliable operation of the wind power generator set is further guaranteed.

Drawings

FIG. 1 is a schematic diagram of a state machine-based pitch system control method according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a state machine control method of a pitch system in a standby mode according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a state machine control method of a pitch system in a normal operating mode according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of a state machine control method of a pitch system in an emergency closed-loop mode according to an embodiment of the present invention;

fig. 5 is a schematic diagram of a state machine control method of a pitch system in an emergency open-loop mode according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be understood in the art that the terms "first," "second," "third," and the like in the description of the invention are used for distinguishing between descriptions and not for indicating or implying relative importance. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In order to solve the technical problems of complex logic, large occupied space memory and low safety of a pitch system control method in the prior art, the invention provides a state machine-based pitch system control method.

The technical solution of the present invention will be described in detail below with reference to the specific embodiments and the accompanying drawings.

Referring to fig. 1, a pitch system control method based on a state machine according to an embodiment of the present invention is applied to a state machine of a pitch system, where the pitch system includes a controller, three axle boxes, and a driver, a motor, an encoder, a first limit switch, and a second limit switch connected to each axle box, and the first limit switch and the second limit switch are redundant to each other, and the control method includes:

determining a plurality of state machine modes of a pitch system, the state machine modes comprising: a standby mode, a normal operating mode, an emergency closed-loop mode and an emergency open-loop mode;

and when the variable pitch system is in any state machine mode, judging whether the variable pitch system meets the state mode switching condition, and if so, controlling different state machine modes to switch.

According to the control method of the variable pitch system based on the state machine, the state machine mode of the variable pitch system is defined based on the state machine, and switching between different state machine modes is controlled through the variable pitch system, so that safe and reliable operation of the wind power generator set is guaranteed, logic is simplified, occupation of space memory is reduced, and action response time of the variable pitch system is shortened.

The pitch control system is simply introduced and mainly comprises a controller, three axle boxes, a driver, a motor, an encoder, a first limit switch and a second limit switch, wherein the driver, the motor, the encoder, the first limit switch and the second limit switch are connected with each other, the controller is connected with the controller in the axle boxes, the controller in the axle boxes is respectively connected with the driver, the motor and the encoder, the driver is connected with the motor, the motor is connected with the encoder, and the controller controls the driver to drive the motor to move until the motor reaches a target position according to a preset target position instruction. It should be noted that each axle box controls one blade and receives a control command from the controller. According to the state sum-based pitch control system control method provided by the embodiment of the invention, for one axle box, the other axle boxes are the same as the axle box. In this implementation, the first limit switch is a 92-degree limit switch, the second limit switch is a 100-degree limit switch, and the positions of the first limit switch and the second limit switch can be modified according to actual requirements, wherein the position of the first limit switch is a second target position, and the position of the second limit switch is a third target position.

Specifically, referring to fig. 1, a pitch system control method based on a state machine provided in an embodiment of the present invention is applied to a state machine of a pitch system, and the control method includes:

determining a plurality of state machine modes of the pitch system, the state machine modes comprising: the state machine mode further comprises a manual operation mode, and the priority and safety of the manual operation mode are higher than those of the standby mode, the normal working mode, the emergency closed-loop mode and the emergency open-loop mode.

And when the variable pitch system is in any state machine mode, judging whether the variable pitch system meets the state mode switching condition, and if so, controlling different state machine modes to switch.

More specifically, the pitch system switches the plurality of state machine modes according to the following steps:

when the variable pitch system is in a standby mode, if a control instruction of the controller is received, switching to a normal working mode; if a first fault is detected, switching to an emergency closed-loop mode, wherein the first fault comprises a non-encoder fault, and the non-encoder fault comprises but is not limited to a safety chain fault and an emergency working condition;

when the variable pitch system is in a normal working mode, if a first fault is detected, switching to an emergency closed-loop mode; if a second fault is detected, switching to an emergency open loop mode, wherein the second fault comprises an encoder fault; if the control instruction is not received, switching to a standby mode, wherein the control instruction comprises an instruction for controlling the motor to move, a reset instruction, a starting instruction and a clearing instruction;

when the variable pitch system is in an emergency closed-loop mode, if a second fault is detected, switching to the emergency open-loop mode; if the first fault is eliminated and the control instruction is received, switching to a normal working mode; if the first fault is eliminated and the control instruction is not received, switching to a standby mode;

and when the variable pitch system is in the emergency open loop mode, if the second fault is eliminated and the control instruction is received, switching to the normal working mode.

It should be noted that, if the pitch system is in the standby mode, the normal operating mode, the emergency closed-loop mode, or the emergency open-loop mode, if the pitch system is connected to the manual operation box, the manual operation mode is switched to. The manual box is common knowledge of those skilled in the art, and those skilled in the art should understand that the pitch system can be controlled according to different function buttons on the manual box. When the variable pitch system is in a manual operation mode, the manual operation box is disconnected, in order to ensure the safety of the variable pitch system, the variable pitch system is switched to an emergency closed-loop mode, and according to a switching method when the variable pitch system is in the emergency closed-loop mode, the variable pitch system is switched to the emergency open-loop mode from the emergency closed-loop mode, or is switched to a normal working mode from the emergency closed-loop mode, or is switched to a standby mode from the emergency closed-loop mode.

Referring to fig. 2, the switching method when the pitch system is in the standby mode includes:

judging whether the variable pitch system is powered on or not, if so, judging whether the variable pitch system is initialized or not, if so, judging whether the variable pitch system is self-checked or not, if so, judging whether the variable pitch system is in a standby mode, and judging whether the variable pitch system is connected to a manual operation box or not;

if the manual operation box is accessed, switching to a manual operation mode, otherwise, judging whether the variable pitch system receives a control instruction;

if a control instruction is received, switching to a normal working mode, and controlling the driver to drive the motor to move by the controller, otherwise, judging whether the variable pitch system detects a first fault;

if the first fault is detected, switching to an emergency closed-loop mode, and controlling a driver to drive the motor to move to a first target position by the controller; and otherwise, returning to judge whether the pitch control system is connected with the manual operation box. Wherein the first target position is an 89 deg. position.

It should be noted that when the pitch system is in the emergency closed loop mode, the controller controls the drive motor to operate at a speed of 5 °/s to the 89 ° position since the encoder is normal.

Referring to fig. 3, the switching method when the pitch system is in the normal operation mode includes:

when the variable pitch system is in a normal working mode, the controller gives a target position and a target speed, the controller controls the driver to drive the motor to move to the target position according to the target speed, and whether the variable pitch system is connected with the manual operation box or not is judged;

if the manual operation box is accessed, switching to a manual operation mode, otherwise, judging whether the variable pitch system detects a first fault;

if the first fault is detected, switching to an emergency closed-loop mode, and controlling a driver to drive a motor to move to a first target position by a controller; otherwise, judging whether the variable pitch system detects a second fault;

if a second fault is detected, switching to an emergency open-loop mode, and controlling the driver to drive the motor to move feathering by the controller until the paddle touches the first limit switch to reach a second target position or touches the third limit switch to reach a third target position; otherwise, judging whether the variable pitch system receives a control instruction;

if the control instruction is not received, switching to a standby mode, controlling the driver to drive the motor to perform deceleration movement by the controller until the motor stops moving, and contracting the brake by the motor, otherwise, controlling the driver to drive the motor to perform movement by the variable pitch system according to the control instruction, and returning to judge whether the variable pitch system is connected with the manual operation box.

It should be noted that, the controller may control in a speed control mode or a position control mode according to a given target position and a target speed, when the controller controls the operation of the pitch system in the position control mode, the driver controls the motor to operate towards the target position at the target speed, and when the controller controls the operation of the pitch system in the speed control mode, the driver controls the motor to operate according to the target speed to reach the target position. When the pitch control system is switched from a normal working mode to a standby mode, the controller controls the driver to enable the driver to drive the motor to decelerate and stop moving, and the motor is braked. When the variable-pitch system is in an emergency open-loop mode, the encoder fails, the controller controls the driver to drive the motor to operate feathering at the maximum allowable speed until the blade touches the first limit switch, and when the first limit switch fails, the controller controls the driver to drive the motor to operate feathering at the maximum allowable speed until the blade touches the second limit switch.

Referring to fig. 4, the switching method when the pitch system is in the emergency closed loop mode includes:

when the variable pitch system is in an emergency closed loop mode, the controller controls the driver to drive the motor to move to the first target position, and whether the variable pitch system is connected to the manual operation box is judged;

if the manual operation box is accessed, switching to a manual operation mode, otherwise, judging whether the variable pitch system detects a second fault;

if the second fault is detected, switching to an emergency open-loop mode, and controlling the driver to drive the motor to move feathering by the controller until the blades reach a second target position or a third target position; otherwise, judging whether the variable pitch system eliminates the first fault;

if the first fault is eliminated and a control instruction is received, switching to a normal working mode, and controlling a driver to drive a motor to move to a target position according to a target speed by a controller; and if the first fault is eliminated and the control instruction is not received, switching to a standby mode, otherwise, returning to judge whether the variable pitch system is connected with the manual operation box.

If the first fault is eliminated and a reset command or a clearing command is received, the mode is switched to a normal mode, the controller sends a command for controlling the motor to move, and the driver drives the motor to move according to the command for controlling the motor to move; and if the first fault is eliminated and the command for controlling the motor to move, the reset command, the clearing command and the starting command are not received, switching to a standby mode. When the paddle reaches the second target position, if the first fault is eliminated and a control instruction is received, switching to a normal working mode; when the blade reaches a third target position, the manual operation box is accessed to the variable pitch system, the manual operation mode is switched to, the blade is operated to a certain position between 0 and 90 degrees, the manual operation box is disconnected, the variable pitch system is switched to be in an emergency closed loop mode, and the variable pitch system is switched to be in a normal working mode according to a switching method from the emergency closed loop mode to the normal working mode.

Referring to fig. 5, the switching method when the pitch system is in the emergency open loop mode includes:

when the variable pitch system is in an emergency open-loop mode, the controller controls the driver to drive the motor to move to the second target position for feathering, if the first limit switch fails, the controller controls the driver to drive the motor to move to the third target position for feathering, and whether the variable pitch system is connected with the manual operation box is judged;

if the manual operation box is accessed, switching to a manual operation mode, otherwise, judging whether the second fault of the variable pitch system is eliminated;

if the second fault is eliminated and a control instruction is received, switching to a normal working mode, and controlling the driver to drive the motor to move to a target position according to a target speed by the controller; and otherwise, returning to judge whether the pitch control system is connected with the manual operation box.

It should be noted that, at any time of the normal operation mode and the emergency closed-loop mode, when the condition for switching to the emergency open-loop mode is met, the emergency open-loop mode can be automatically switched to, the driver drives the motor to move, the paddle is driven to move feathering until the second target position or the third target position is reached, and the movement is stopped.

According to the control method of the variable pitch system based on the state machine, the state machine mode of the variable pitch system is defined based on the state machine, and switching between different state machine modes is controlled through the variable pitch system, so that safe and reliable operation of the wind power generator set is guaranteed, logic is simplified, occupation of space memory is reduced, and action response time of the variable pitch system is shortened.

An embodiment of the present invention further provides a pitch system, including a state machine, where the state machine is configured to execute the method described above.

The embodiment of the present invention further provides a state machine applied to a pitch system, including:

determining a plurality of state machine modes of a pitch system, the state machine modes comprising: a standby mode, a normal operating mode, an emergency closed-loop mode and an emergency open-loop mode;

and when the variable pitch system is in any state machine mode, judging whether the variable pitch system meets the state mode switching condition, and if so, controlling different state machine modes to switch.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.