Wind power variable pitch motor angle automatic calibration strategy based on limit switch

Abstract

The invention discloses an automatic calibration strategy for the angle of a wind power variable pitch motor based on a limit switch. The automatic calibration strategy comprises the following steps that S1, a rotary transformer breaks down; s2, the blades are subjected to open-loop feathering to the position of a limiting switch; s3, judging whether the resolver fault is eliminated or not, and if yes, entering the step S4; if not, not executing any operation; s4, writing the fixed angle of the limit switch as a calibration angle into a motor coordinate system; s5, a fan is started, and paddles are opened; s6, whether the starting proximity switch breaks down or not is judged, if yes, feathering of the paddle is conducted to the position of the limiting switch, and variable pitch system angle calibration fails; if not, entering the step S7; and S7, the calibration is successful, and the system can operate normally. According to the method, angle calibration can be automatically carried out after a rotary transformer fault occurs in the variable pitch system, time waste caused by manual zero setting of a maintainer on a tower is avoided, the operation efficiency of the wind generating set is improved, the angle of the variable pitch system is calibrated based on the limiting switch, and the zero setting precision is more reliable compared with visual inspection of the maintainer.

Description

Technical Field

[0001] The invention relates to the technical field of wind power generation, and in particular to an automatic calibration strategy for a wind power variable pitch motor angle based on a limit switch. Background Art

[0002] Wind energy is a new, renewable and environmentally friendly energy. As one of the core systems of wind turbines, the variable pitch system has high requirements for its reliability, safety and rationality of fault handling.

[0003] Before the wind turbine pitch system can operate normally, it needs to be calibrated at zero point to determine the coordinate zero point of the pitch system. During the zero point calibration, the operator needs to enter the wind turbine hub and rotate the pitch motor in manual mode to make the outer ring of the blade coincide with the zero point position of the hub to achieve zero point calibration. After the zero point calibration is completed, the blades will operate at the angle sent by the master control based on the zero point to achieve wind power generation.

[0004] During the operation of the variable pitch system, the current angle of the blade is fed back through the motor's resolver. When the resolver signal is disturbed or fails, the motor will lose the current angle and the blade will be aligned to the limit switch. After the resolver returns to normal, the motor angle remains at the time of the failure, which does not match the position of the limit switch. On-site personnel need to go up the tower and enter the hub to re-calibrate the zero point before the wind turbine can be restored. If there is a strong wind or an offshore unit, it will delay a lot of time, seriously affecting the power generation of the wind turbine. Summary of the invention

[0005] In response to the above-mentioned deficiencies in the prior art, the present patent application provides an automatic calibration strategy for the wind turbine pitch motor angle based on a limit switch. When a wind turbine loses its angle and pitches to the limit switch position due to a resolver failure, if the system detects that the resolver has returned to normal, it will automatically use the angle of the limit switch installation position as a reference angle to recalibrate the current angle of the motor, thereby restoring the operation of the pitch motor and greatly reducing the downtime caused by the failure.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] A wind turbine pitch motor angle automatic calibration strategy based on a limit switch includes the following steps:

[0008] S1: Resolver failure: The resolver of the pitch motor fails and the motor loses its angle;

[0009] S2: The blade opens and feathers to the limit switch;

[0010] S3: Determine whether the resolver fault is eliminated. If so, proceed to step S4; if not, do not perform any operation;

[0011] S4: Write the fixed angle where the limit switch is located as the calibration angle into the motor coordinate system;

[0012] S5: The fan starts and the blades open;

[0013] S6: Determine whether a proximity switch failure has occurred. If so, the blades are aligned to the limit switch and the pitch system angle calibration fails. If not, proceed to step S7.

[0014] S7: Calibration is successful and the system can operate normally.

[0015] Among them, in step S6, the pitch system angle calibration fails and manual calibration is required.

[0016] In step S4, the mechanical position where the limit switch is installed is the fixed angle at which the limit switch is located.

[0017] Wherein, in step S6, if the proximity switch does not generate a fault, the error of the angle value of the pitch system recalibrated is within the allowable range.

[0018] In summary, the wind turbine pitch motor angle automatic calibration strategy based on limit switches has the following beneficial effects:

[0019] 1. The present invention can automatically calibrate the angle after a resolver failure occurs in the pitch system, eliminating the time wasted by maintenance personnel climbing up the tower to manually calibrate the angle, thereby improving the operating efficiency of the wind turbine generator set.

[0020] 2. The present invention calibrates the angle of the variable pitch system based on the limit switch, which is more reliable than relying on the maintenance personnel to visually check the zero accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The present invention is a flow chart of a limit switch-based wind turbine pitch motor angle automatic calibration strategy. DETAILED DESCRIPTION

[0022] The present invention is further described in detail below in conjunction with the accompanying drawings. In the description of the present invention, it should be understood that the directions or positional relationships indicated by directional words such as "upper, lower" and "top, bottom" are usually based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description. Unless otherwise stated, these directional words do not indicate or imply that the devices or components referred to must have a specific direction or be constructed and operated in a specific direction, and therefore cannot be understood as limiting the scope of protection of the present invention; the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0023] like Figure 1 As shown, a wind turbine pitch motor angle automatic calibration strategy based on a limit switch includes the following steps:

[0024] S1: Resolver failure: The resolver of the pitch motor fails and the motor loses its angle;

[0025] S2: The blade opens and feathers to the limit switch;

[0026] S3: Determine whether the resolver fault is eliminated. If so, proceed to step S4; if not, do not perform any operation;

[0027] S4: Write the fixed angle where the limit switch is located as the calibration angle into the motor coordinate system; the mechanical position where the limit switch is installed is the fixed angle where the limit switch is located;

[0028] S5: The fan starts and the blades open;

[0029] S6: Determine whether a proximity switch fault has occurred. If so, the blades are aligned to the limit switch, and the pitch system angle calibration fails, requiring manual calibration on the tower. If not, the proximity switch has not failed, and the error of the angle value of the pitch system recalibrated is within the allowable range; then proceed to step S7;

[0030] S7: Calibration is successful and the system can operate normally.

[0031] When the resolver of the variable pitch system fails and triggers the open-loop feathering shutdown to the limit switch, the system will automatically detect whether the resolver fault has been eliminated. When the resolver returns to normal, because the blade stops at the position of the limit switch, and the mechanical position of the limit switch installation is fixed, the system will assign this fixed angle as the current angle value to the variable pitch motor, thereby restoring the angle value of the variable pitch system. After the wind turbine starts normally, the blade runs to the position of the proximity switch. If the proximity switch does not report a fault, it proves that the error of the recalibrated angle value of the variable pitch system is within the allowable range and the system can operate normally.

[0032] The specific implementation includes the following steps:

[0033] 1. Complete the wiring of related hardware and the replacement of pitch control and main control programs;

[0034] 2. In the automatic operation mode of variable pitch, unplug the motor resolver cable to simulate a resolver failure, and open the propeller loop to the limit switch;

[0035] 3. Re-insert the resolver connector. After the system detects that the resolver fault has been restored, it will automatically write the angle position of the limit switch into the current angle of the pitch system.

[0036] 4. The main control sends a reset signal to reset all faults and then start the machine;

[0037] 5. The propeller blades start to propel and run to the proximity switch without triggering the proximity switch fault.

[0038] Finally, it should be noted that those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A wind turbine pitch motor angle automatic calibration strategy based on limit switches, characterized in that: The following steps are involved: S1: Resolver failure: The resolver of the pitch motor fails and the motor loses its angle; S2: The blade opens and feathers to the limit switch; S3: Determine whether the resolver fault is eliminated. If so, proceed to step S4; if not, do not perform any operation; S4: Write the fixed angle where the limit switch is located as the calibration angle into the motor coordinate system; S5: The fan starts and the blades open; S6: Determine whether a proximity switch failure has occurred. If so, the blades are aligned to the limit switch and the pitch system angle calibration fails. If not, proceed to step S7. S7: Calibration is successful and the system can operate normally.

2. According to claim 1, a wind turbine pitch motor angle automatic calibration strategy based on a limit switch is characterized in that: In step S6, the pitch system angle calibration fails and manual calibration is required.

3. The wind turbine pitch motor angle automatic calibration strategy based on limit switch according to claim 1 is characterized in that: In step S4, the mechanical position where the limit switch is installed is the fixed angle at which the limit switch is located.

4. The wind turbine pitch motor angle automatic calibration strategy based on limit switches according to claim 1 is characterized in that: In step S6, if the proximity switch does not indicate a fault, the error of the newly calibrated angle value of the pitch system is within the allowable range.

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