Method for testing and eliminating torsional resonance of power generation system and engine shafting

Abstract

The invention belongs to the technical field of aviation power generation systems, and particularly relates to a method for testing and eliminating torsional resonance of a power generation system and an engine shafting, and the method comprises the steps: arranging a tester collection system on the aviation power generation system, and collecting an output voltage and a generator excitation current; and after decomposition, judging whether the periodic change frequency of the generator exciting current coincides with the torsional inherent frequency of the engine shafting or the difference value is smaller than a set value, if so, judging that torsional resonance occurs, and controlling the switching frequency of the power field effect MOS tube and the parameters of a feedback loop to change the periodic change frequency and amplitude of the generator exciting current. Whether the power generation system and an engine shafting generate torsional resonance or not is judged by testing changes of excitation current and voltage output frequency of a generator in the power generation system, and meanwhile, parameters of a voltage regulating circuit of a generator controller are adjusted to eliminate the torsional resonance generated by the power generation system and the engine shafting. Torsional resonance of a power generation system and an engine shafting can be tested and eliminated, and safe operation of the system is guaranteed.

Description

Technical Field

[0001] The present application belongs to the technical field of aviation power generation systems, and in particular, relates to a method for testing and eliminating torsional resonance of a power generation system and an engine shaft system. Background Art

[0002] The aircraft generator is fixed to the engine accessory case by a quick-release clamp, and the energy is transmitted by the meshing of the splines inside the engine accessory case and the external splines of the aircraft generator, converting the engine mechanical energy into electrical energy. The aircraft power generation system consists of a generator and a generator controller. When the generator is working, the generator excitation current needs to be adjusted by the generator controller to achieve continuous and stable voltage output. When the frequency of the generator rotor torque change is close to or coincides with the natural frequency of the engine shaft system, torsional resonance occurs. The current method of checking torsional resonance is to set a stress plate on the input shaft of the aircraft generator to test whether the stress on the input shaft changes alternately, thereby judging whether torsional resonance occurs.

[0003] However, after long-term use, the stress gauge may become insensitive or respond incorrectly, so how to more effectively judge torsional resonance is a problem that needs to be solved. Summary of the invention

[0004] The purpose of the present application is to provide a method for testing and eliminating torsional resonance of a power generation system and an engine shaft system, so as to solve the problem of low reliability of torsional resonance detection using stress sheets.

[0005] The technical solution of the present application is: a method for testing and eliminating torsional resonance of a power generation system and an engine shaft system, comprising:

[0006] A tester acquisition system is set up on the aviation power generation system. When the generator is driven to rotate by the engine accessory case, the generator controller adjusts the generator excitation current and output voltage; the tester acquisition system is divided into two paths and respectively acquires the generator excitation current and the main generator stator output voltage, and transmits them to the tester acquisition system to form an acquisition signal;

[0007] The tester acquisition system decomposes the collected signal to obtain the periodic change frequency of the generator excitation current and obtain the torsional natural frequency of the engine shaft system; determines whether the periodic change frequency of the generator excitation current coincides with the torsional natural frequency of the engine shaft system or the difference is less than the set value, if so, determines that torsional resonance occurs and executes the next step; if not, determines that torsional resonance does not occur; when torsional resonance occurs between the power generation system and the engine shaft system, controls and adjusts the switching frequency of the power field effect MOS tube connected to the excitation winding in the voltage regulating circuit of the generator controller and the feedback loop parameters to change the periodic change frequency and amplitude of the generator excitation current, and then collects the periodic change frequency of the generator excitation current and the fluctuation of the generator output voltage output frequency again through the tester acquisition system to determine whether the torsional resonance between the power generation system and the engine shaft system is eliminated; if so, solves the problem of torsional resonance between the power generation system and the engine shaft system.

[0008] Preferably, if the torsional natural frequency of the engine shaft system is unknown, the output voltage output frequency of the generator is calculated, and by observing the fluctuation of the output voltage output frequency of the generator, it is determined whether torsional resonance occurs between the power generation system and the engine shaft system.

[0009] Preferably, FTT is used to decompose the collected signal.

[0010] Preferably, the tester acquisition system is provided with a data classification storage module, a data processing module and a data judgment module; the data classification storage module can classify and store the generator excitation current, output voltage and engine shaft system torsional natural frequency; the data processing module can decompose the acquired signal to obtain the periodic change frequency of the generator excitation current; the data judgment module can call the engine shaft system torsional natural frequency and the generator excitation current periodic change frequency to determine whether there is torsional resonance.

[0011] Preferably, the generator excitation current, output voltage, generator excitation current FIT value and main generator stator output voltage frequency are sorted according to time, and the generator excitation current is associated with the generator excitation current FIT value, output voltage and main generator stator output voltage frequency to obtain the excitation current instantaneous change diagram and the output voltage instantaneous change diagram.

[0012] Preferably, the generator controller is provided with a frequency step and an amplitude step; when torsional resonance occurs, the periodic frequency and amplitude of the generator excitation current are adjusted upward or downward by changing the frequency step and the amplitude step.

[0013] The method for testing and eliminating torsional resonance between the power generation system and the engine shaft system of the present application sets a tester acquisition system on the aviation power generation system, determines whether torsional resonance occurs between the power generation system and the engine shaft system by testing the changes in the excitation current and voltage output frequency of the generator in the power generation system, and simultaneously adjusts the parameters of the voltage regulating circuit of the generator controller to eliminate the torsional resonance between the power generation system and the engine shaft system. The reliability is high, and the torsional resonance between the power generation system and the engine shaft system can be tested and eliminated to ensure the safe operation of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solution provided by the present application, the following is a brief introduction to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present application.

[0015] Figure 1 Block diagram for testing and eliminating torsional resonance between the power generation system and the engine shafting for this application;

[0016] Figure 2 This application is a generator controller voltage regulating circuit.

[0017] 1. Engine input shaft. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] A method for testing and eliminating torsional resonance of power generation system and engine shafting, such as Figure 1 The aviation power generation system consists of a generator and a generator controller. When the generator is working, the generator controller needs to adjust the generator excitation current to achieve continuous and stable voltage output. When the generator excitation current in the power generation system has a periodic change frequency, the generator input shaft 1 produces the same torque change frequency, and its frequency is close to or coincides with a certain order torsional natural frequency of the engine shaft system, it causes torsional resonance between the power generation system and the engine shaft system.

[0020] The steps include:

[0021] Step S100, a tester acquisition system is set on the aviation power generation system. When the generator is driven to rotate by the engine accessory case, the generator controller adjusts the generator excitation current and output voltage; the tester acquisition system is divided into two paths and respectively acquires the generator excitation current and the main generator stator output voltage, and transmits them to the tester acquisition system to form an acquisition signal;

[0022] Step S200, the tester acquisition system decomposes the acquisition signal, obtains the periodic frequency of the generator excitation current, and obtains the torsional natural frequency of the engine shaft system; determines whether the periodic frequency of the generator excitation current coincides with the torsional natural frequency of the engine shaft system or the difference is less than the set value, if so, it is determined that torsional resonance occurs, and the next step is executed; if not, it is determined that torsional resonance does not occur. The set value is set according to experience.

[0023] If the torsional natural frequency of the engine shaft system is unknown, the output voltage and frequency of the generator output can be calculated. By observing the fluctuation of the output voltage and frequency of the generator output, it can be determined whether torsional resonance occurs between the power generation system and the engine shaft system.

[0024] Preferably, FTT is used to decompose the collected signal. FTT is Fourier transform, which can decompose a signal into sinusoidal signals of different frequencies and amplitudes.

[0025] Preferably, the tester acquisition system is provided with a data classification storage module, a data processing module and a data judgment module; the data classification storage module can classify and store the generator excitation current, output voltage and engine shaft system torsional natural frequency; the data processing module can decompose the acquired signal to obtain the periodic change frequency of the generator excitation current; the data judgment module can call the engine shaft system torsional natural frequency and the generator excitation current periodic change frequency to determine whether there is torsional resonance.

[0026] Preferably, the generator excitation current, output voltage, generator excitation current FIT value and main generator stator output voltage frequency are sorted according to time, and the generator excitation current is associated with the generator excitation current FIT value, output voltage and main generator stator output voltage frequency to obtain the excitation current instantaneous change diagram and the output voltage instantaneous change diagram for easy viewing.

[0027] Step S300: When the power generation system and the engine shaft system have torsional resonance, control and adjust the voltage regulating circuit of the generator controller (see Figure 2 ) by changing the switching frequency and feedback loop parameters of the power field effect MOS tube connected to the excitation winding to change the periodic frequency and amplitude of the generator excitation current, and then the tester acquisition system is used to collect the periodic frequency of the generator excitation current and the fluctuation of the generator output voltage output frequency to determine whether the torsional resonance between the power generation system and the engine shaft system is eliminated; if so, the problem of torsional resonance between the power generation system and the engine shaft system is solved.

[0028] Preferably, the generator controller is provided with a changing frequency step and an amplitude step; when torsional resonance occurs, the periodic changing frequency and amplitude of the generator excitation current are adjusted upward or downward by changing the frequency step and the amplitude step to achieve stable regulation control.

[0029] In summary, the present application sets up a tester acquisition system on the aviation power generation system, and determines whether the power generation system and the engine shaft system have torsional resonance by testing the changes in the excitation current and voltage output frequency of the generator in the power generation system, and at the same time adjusts the parameters of the voltage regulating circuit of the generator controller to eliminate the torsional resonance between the power generation system and the engine shaft system. The reliability is high, and the torsional resonance between the power generation system and the engine shaft system can be tested and eliminated to ensure the safe operation of the system.

[0030] Finally, it should be noted that: the drawings of the embodiments disclosed in the present invention only involve structures related to the embodiments disclosed in the present invention, and other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of the present invention can be combined with each other;

[0031] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for testing and eliminating torsional resonance of a power generation system and an engine shaft system, characterized in that: include: A tester acquisition system is set up on the aviation power generation system. When the generator is driven to rotate by the engine accessory case, the generator controller adjusts the generator excitation current and output voltage; The tester acquisition system is divided into two paths and respectively acquires the generator excitation current and the main generator stator output voltage, and transmits them to the tester acquisition system to form acquisition signals; The tester acquisition system decomposes the collected signal to obtain the periodic change frequency of the generator excitation current and obtain the torsional natural frequency of the engine shaft system; determines whether the periodic change frequency of the generator excitation current coincides with the torsional natural frequency of the engine shaft system or the difference is less than the set value, if so, determines that torsional resonance occurs and executes the next step; if not, determines that torsional resonance does not occur; when torsional resonance occurs between the power generation system and the engine shaft system, controls and adjusts the switching frequency of the power field effect MOS tube connected to the excitation winding in the voltage regulating circuit of the generator controller and the feedback loop parameters to change the periodic change frequency and amplitude of the generator excitation current, and then collects the periodic change frequency of the generator excitation current and the fluctuation of the generator output voltage output frequency again through the tester acquisition system to determine whether the torsional resonance between the power generation system and the engine shaft system is eliminated; if so, solves the problem of torsional resonance between the power generation system and the engine shaft system.

2. The method for testing and eliminating torsional resonance of a power generation system and an engine shaft system as claimed in claim 1, characterized in that: If the torsional natural frequency of the engine shaft system is unknown, the output voltage and frequency of the generator output are calculated, and by observing the fluctuation of the output voltage and frequency of the generator output, it is determined whether torsional resonance occurs between the power generation system and the engine shaft system.

3. The method for testing and eliminating torsional resonance of a power generation system and an engine shaft system as claimed in claim 1, characterized in that: FTT is used to decompose the collected signal.

4. The method for testing and eliminating torsional resonance of a power generation system and an engine shaft system as claimed in claim 1, characterized in that: The tester acquisition system is provided with a data classification storage module, a data processing module and a data judgment module; the data classification storage module can classify and store the generator excitation current, output voltage and engine shaft system torsional natural frequency; the data processing module can decompose the acquired signal to obtain the periodic change frequency of the generator excitation current; the data judgment module can call the engine shaft system torsional natural frequency and the generator excitation current periodic change frequency to determine whether there is torsional resonance.

5. The method for testing and eliminating torsional resonance of a power generation system and an engine shaft system as claimed in claim 1, characterized in that: The generator excitation current, output voltage, generator excitation current FIT value and main generator stator output voltage frequency are sorted according to time, and the generator excitation current is associated with the generator excitation current FIT value, output voltage and main generator stator output voltage frequency to obtain the excitation current instantaneous change diagram and the output voltage instantaneous change diagram.

6. The method for testing and eliminating torsional resonance of a power generation system and an engine shaft system as claimed in claim 1, characterized in that: The generator controller is provided with a frequency change step and an amplitude change step; when torsional resonance occurs, the periodic frequency and amplitude of the generator excitation current are adjusted upward or downward by changing the frequency step and the amplitude step.

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