Hovercraft propulsion pitch angle deviation correction method

Abstract

A hovercraft propulsion pitch angle deviation correction method comprises the steps that the maximum allowable angle difference # imgabs0 # of an air propeller and a pitch feedback value is set, the angle theta 1 of the air propeller and the angle theta 2 of the pitch feedback value are obtained, and the angle difference theta alpha of the air propeller and the pitch feedback value is calculated; obtaining an angle deviation theta3 when the decoder of the rotary transformer is set to be at a zero position; according to the matching characteristics of the propeller, the corrected allowable deviation angle difference # imgabs 1 # of the feedback value of the air propeller and the pitch is obtained; and when a screw pitch changing instruction is carried out, the propeller works at different rotating speeds under different screw pitches according to the matching characteristics of the propeller and the propeller. According to the sudden change of the working condition of the gas turbine, checking the relationship between the angle difference theta alpha of the air propeller and the pitch feedback value and # imgabs2 # after shutdown, and judging whether the pitch angle needs to be corrected or not; if theta alpha is larger than # imgabs3 #, the screw pitch action is stopped, and screw pitch angle deviation correction is conducted; and if theta alpha is smaller than or equal to # imgabs4 #, the air propeller is controlled to continue to act according to the propeller matching characteristic, and the sailing safety is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of hovercraft, in particular to a method for correcting propulsion pitch angle deviation of a hovercraft. Background Art

[0002] Hovercraft generally includes three propulsion propellers on the left, middle and right. The propulsion main engine provides power to drive the propellers to rotate at high speed. The propeller load is changed by controlling the pitch, thereby driving the hovercraft forward. The hovercraft moves forward and turns by adjusting the blade angle of the air propeller and the change of the air flow entering the propeller device and the direction of the air flow. When manipulating the pitch, if the pitch angle of the propulsion propeller differs too much from the pitch feedback value, the operator cannot display the real air propeller angle through the pitch feedback value, which will affect the boat's navigation posture and have a significant impact on navigation safety. Summary of the invention

[0003] In view of the shortcomings of the above-mentioned existing production technology, the applicant provides a method for correcting the propulsion pitch angle offset of a hovercraft, thereby effectively solving the problems existing in the existing technology, ensuring safety, and greatly improving the safety factor.

[0004] The technical solution adopted by the present invention is as follows: A method for correcting propulsion pitch angle deviation of a hovercraft comprises the following steps: Step 1: Set the maximum allowable angle difference between the air propeller and the pitch feedback value ; Step 2: Get the air propeller angle i 1 and pitch feedback value angle i 2; Step 3: Obtain the angle deviation when the resolver decoder is set to zero i 3; Step 4: Calculate the angle difference between the air propeller and the pitch feedback value i α ; Step 5: According to the propeller matching characteristics, obtain the corrected air propeller and pitch feedback value allowable deviation angle difference ; Step 6: Check the angle difference between the air propeller and the pitch feedback value according to the sudden change of the engine operating condition i α and The relationship between the two can be used to determine whether the pitch angle needs to be corrected. Step 7: If | i α |>| |Then stop the pitch action and make pitch angle offset correction; if | i α |≤| |, the air propeller is controlled to continue to move according to the propeller matching characteristics; Step 8: Determine whether the pitch is in place, if not, repeat steps 2 to 7.

[0005] Its further technical solution is: Set the maximum allowable angle difference of the initial pitch =1°.

[0006] Corrected allowable angle difference Less than or equal to the maximum allowable angle difference of the initial pitch .

[0007] The propulsion pitch angle range is -28°~+48°.

[0008] When the propulsion pitch is working, the engine operating condition may change suddenly. After stopping, check the angle difference between the air propeller and the pitch feedback value. i α and The relationship between the pitch angle and the pitch angle is used to determine whether the pitch angle needs to be corrected. The judgment method is: If | i α |>| |The pitch action is stopped and the pitch angle offset correction is performed by setting the resolver decoder to zero.

[0009] The specific process is as follows: due to the angle deviation when the resolver decoder is set to zero i 3， Adjust the air propeller angle to ± i 3°, then adjust the pitch feedback value angle to ( i 2- i 1+(± i 3))°, short-circuit the zero position terminal on the resolver decoder and reset it; if the reset is completed | i α |≤| |, the pitch angle offset correction is successfully completed, otherwise repeat the above operation.

[0010] The beneficial effects of the present invention are as follows: The present invention determines whether the pitch angle needs to be corrected by measuring the propeller angle difference, which can effectively prevent the navigation posture of the hovercraft from being affected by excessive angle difference, and is of great significance in ensuring the safe navigation of the hovercraft.

[0011] And the adjustment is also very convenient. When the propulsion pitch is working, according to the sudden change of the engine working condition, check the angle difference between the air propeller and the pitch feedback value after stopping. i α and The relationship between the two can be used to determine whether the pitch angle needs to be corrected.

[0012] If | i α |>| |The pitch action is stopped and the pitch angle offset correction is performed by setting the resolver decoder to zero.

[0013] Due to the angle deviation when the resolver encoder is set to zero i 3. Adjust the air propeller angle to ± i 3°, then adjust the pitch feedback value angle to ( i 2- i 1+(± i 3))°, short-circuit the zero position terminal on the resolver decoder and reset it; if the reset is completed | i α |≤| |, the pitch angle offset correction is successfully completed, otherwise repeat the above operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a structural block diagram of the propulsion pitch of the hovercraft of the present invention.

[0015] Figure 2 The present invention is a flow chart of the hovercraft propulsion pitch angle offset correction method. DETAILED DESCRIPTION

[0016] The specific implementation of the present invention will be described below in conjunction with the accompanying drawings.

[0017] like Figure 1 and Figure 2 The method for correcting the propulsion pitch angle offset of a hovercraft described in this embodiment includes the following steps: Step 1: Set the maximum allowable angle difference between the air propeller and the pitch feedback value ; Step 2: Get the air propeller angle i 1 and pitch feedback value angle i 2; Step 3: Obtain the angle deviation when the resolver decoder is set to zero i 3; Step 4: Calculate the angle difference between the air propeller and the pitch feedback value i α ; Step 5: According to the propeller matching characteristics, obtain the corrected air propeller and pitch feedback value allowable deviation angle difference ; Step 6: Check the angle difference between the air propeller and the pitch feedback value according to the sudden change of the engine operating condition iα and The relationship between the two can be used to determine whether the pitch angle needs to be corrected. Step 7: If | i α |>| |Then stop the pitch action and make pitch angle offset correction; As | i α |≤| |, the air propeller is controlled to continue to move according to the propeller matching characteristics; Step 8: Determine whether the pitch is in place, if not, repeat steps 2 to 7.

[0018] Set the maximum allowable angle difference of the initial pitch =1°.

[0019] Corrected allowable angle difference Less than or equal to the maximum allowable angle difference of the initial pitch .

[0020] The propulsion pitch angle range is -28°~+48°.

[0021] When the propulsion pitch is working, the engine operating condition may change suddenly. After stopping, check the angle difference between the air propeller and the pitch feedback value. i α and The relationship between the pitch angle and the pitch angle is used to determine whether the pitch angle needs to be corrected. The judgment method is: If | i α |>| |The pitch action is stopped and the pitch angle offset correction is performed by setting the resolver decoder to zero.

[0022] The specific process is as follows: due to the angle deviation when the resolver decoder is set to zero i 3. Adjust the air propeller angle to ± i 3°, then adjust the pitch feedback value angle to ( i 2- i 1+(± i 3))°, short-circuit the zero position terminal on the resolver decoder and reset it; if the reset is completed | i α |≤| |, the pitch angle offset correction is successfully completed, otherwise repeat the above operation.

[0023] This embodiment provides a method for correcting the propulsion pitch angle offset of a hovercraft. Figure 2 As shown, the following steps are included: Example: When the hovercraft is sailing, the operating value of the 2# propulsion engine changes suddenly. During the shutdown inspection, it is found that the angle deviation between the 2# air propeller and the pitch feedback value is too large.

[0024] Step 1: According to the control system logic instruction, the maximum allowable angle difference between the air propeller and the pitch feedback value is set to 1°.

[0025] Step 2: The measured air propeller angle is 30° and the pitch feedback angle is 25°.

[0026] Step 3: After testing, it is found that the angle of the resolver decoder is -0.5° when it is set to zero.

[0027] Step 4: According to the propeller matching characteristics, the corrected air propeller and pitch feedback value are allowed to have an angle difference of 0.5°.

[0028] Step 5: After checking, it is found that the angle difference between the air propeller and the pitch feedback value is 5°> the corrected allowable deviation angle difference of 0.5°, and the pitch angle needs to be corrected.

[0029] Step 6: Since the resolver decoder has an angle deviation of 0.5°, the actuator cannot be accurately adjusted to the zero pitch value when it is set to zero, so the air propeller angle is adjusted to -0.5°. At this time, the pitch feedback value angle is adjusted to (25-30+ (-0.5))°.

[0030] Step 7: Short-circuit the zero position terminal on the resolver decoder and reset the pitch feedback value. The angle value after reset is -0.5°, which is consistent with the air propeller angle. i α |=0≤| |, the correction is completed. If there is still a certain deviation after the setting, repeat the above operation.

[0031] The above description is an explanation of the present invention, not a limitation of the present invention. The scope of the present invention is defined in the claims. Any form of modification may be made within the scope of protection of the present invention.

Claims

1. A method for correcting propulsion pitch angle deviation of a hovercraft, characterized in that: The steps are as follows: Step 1: Set the maximum allowable angle difference between the air propeller and the pitch feedback value ; Step 2: Get the air propeller angle θ 1 and pitch feedback value angle θ 2; Step 3: Obtain the angle deviation when the resolver decoder is set to zero θ 3; Step 4: Calculate the angle difference between the air propeller and the pitch feedback value θ α ; Step 5: According to the propeller matching characteristics, obtain the corrected air propeller and pitch feedback value allowable deviation angle difference ; Step 6: Check the angle difference between the air propeller and the pitch feedback value according to the sudden change of the engine operating condition θ α and The relationship between the two can be used to determine whether the pitch angle needs to be corrected. Step 7: If | θ α |>| |Then stop the pitch action and make pitch angle offset correction; if | θ α |≤| |, the air propeller is controlled to continue to move according to the propeller matching characteristics; Step 8: Determine whether the pitch is in place, if not, repeat steps 2 to 7.

2. A method for correcting propulsion pitch angle deviation of a hovercraft as claimed in claim 1, characterized in that: Set the maximum allowable angle difference of the initial pitch =1°.

3. A method for correcting propulsion pitch angle deviation of a hovercraft as claimed in claim 2, characterized in that: Corrected allowable angle difference Less than or equal to the maximum allowable angle difference of the initial pitch .

4. A method for correcting propulsion pitch angle deviation of a hovercraft as claimed in claim 1, characterized in that: The propulsion pitch angle range is -28°~+48°.

5. The method for correcting propulsion pitch angle deviation of a hovercraft according to claim 1, characterized in that: When the propulsion pitch is working, the engine operating condition may change suddenly. After stopping, check the angle difference between the air propeller and the pitch feedback value. θ α and The relationship between the pitch angle and the pitch angle is used to determine whether the pitch angle needs to be corrected. The judgment method is: If | θ α |>| |The pitch action is stopped and the pitch angle offset correction is performed by setting the resolver decoder to zero.

6. A method for correcting propulsion pitch angle deviation of a hovercraft as claimed in claim 5, characterized in that: The specific process is as follows: due to the angle deviation when the resolver decoder is set to zero θ 3， Adjust the air propeller angle to ± θ 3°, then adjust the pitch feedback value angle to ( θ 2- θ 1+(± θ 3))°, short-circuit the zero position terminal on the resolver decoder and reset it; if the reset is completed | θ α |≤| |, the pitch angle offset correction is successfully completed, otherwise repeat the above operation.

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