CN-121990135-A - Ship main engine active vibration reduction method and device based on double-threshold discrimination

CN121990135ACN 121990135 ACN121990135 ACN 121990135ACN-121990135-A

Abstract

The invention provides a ship main engine active vibration damping method and device based on double-threshold judgment, wherein the method comprises the steps of collecting vibration signals of a ship main engine in real time and converting the vibration signals into electric signals, wherein the electric signals are voltage signals or charge signals, performing analog-digital conversion and digital band-pass filtering processing on the electric signals to separate vibration frequency bands of main engine characteristics, determining vibration damping modes for damping the ship main engine based on the vibration frequency bands by adopting a double-threshold hysteresis judgment mechanism, wherein the vibration damping modes comprise a passive vibration damping mode and an active vibration damping mode, and determining the value of dynamic reverse acting force opposite to the vibration phase of the main engine when the active vibration damping mode is started, and actively counteracting the vibration of the main engine. The invention obviously improves the running stability and safety of the ship main engine and solves the problem that the prior art is difficult to actively damp under complex working conditions.

Inventors

WANG HONGGUO
ZHANG SHUGUANG
Ma Houbiao
LI XINZE
LI XINCHENG
ZHANG ZEQUN

Assignees

江苏科技大学

Dates

Publication Date: 20260508
Application Date: 20260319

Claims (10)

1. The ship main engine active vibration reduction method based on double-threshold discrimination is characterized by comprising the following steps of: Collecting vibration signals of a ship host in real time, and converting the vibration signals into electric signals, wherein the electric signals are voltage signals or charge signals; Performing analog-to-digital conversion and digital band-pass filtering processing on the electric signals to separate out vibration frequency bands of the host machine characteristics; Based on the vibration frequency band, a dual-threshold hysteresis judging mechanism is adopted to determine a vibration damping mode for damping the ship main engine, wherein the vibration damping mode comprises a passive vibration damping mode and an active vibration damping mode; When the active vibration reduction mode is started, the value of dynamic reverse acting force opposite to the vibration of the host machine is determined, and the vibration of the host machine is actively counteracted.
2. The method for actively damping vibration of a marine host based on dual-threshold discrimination according to claim 1, wherein performing analog-to-digital conversion and digital bandpass filtering processing on the electrical signal to separate out a vibration band of a host characteristic comprises: Converting the electric signal into a high-precision digital signal by adopting Delta-Sigma analog-digital conversion logic, differential integral modulation and noise shaping technology; And separating out the vibration frequency band of the host computer characteristic through a digital band-pass filter on the basis of a linear time-invariant system, wherein the linearity of the linear time-invariant system meets the superposition and the second property.
3. The dual threshold discrimination-based marine vessel main engine active damping method according to claim 2, wherein the following band separation logic is executed when performing the digital band pass filtering process: The high-pass part filters out very low frequency interference and the low-pass part filters out high frequency noise.
4. The method for actively damping vibration of a marine host based on dual-threshold discrimination according to claim 1, wherein the dual-threshold hysteresis discrimination mechanism is: Executing a passive vibration reduction mode when the vibration intensity is within a stop threshold; And when the vibration intensity exceeds a starting threshold, executing an active vibration reduction mode, wherein the active vibration reduction mode is realized by adopting a composite framework of a PID control algorithm and an FxLMS algorithm based on feedforward compensation.
5. The method for actively damping vibration of a marine main engine based on dual threshold discrimination according to claim 4, wherein the PID control algorithm based on feedforward compensation comprises feedforward control and feedback control; The feedforward control is that the required compensation quantity is determined according to the known characteristics of the input signal of the system or the external disturbance; The feedback control is to adjust the system error through proportional, integral and differential actions.
6. The method for actively damping vibration of a marine host machine based on dual threshold discrimination of claim 1, wherein after determining a value of dynamic opposing force opposing vibration phase of the host machine, comprising: Converting the dynamic reverse acting force into a digital control sequence through scaling and zero offset processing; using Delta-Sigma ) And the digital control sequence is processed by a modulation algorithm to obtain an analog voltage signal and the analog voltage signal is transmitted to a hydraulic valve of the ship host.
7. The dual threshold discrimination based active damping method for a marine host machine of claim 6, wherein actively counteracting host machine vibrations comprises: According to the analog voltage signal, high-pressure oil flow of a hydraulic actuator of the ship host is regulated, and dynamic pressure difference is established at two sides of a piston; And a piston rod of the hydraulic actuator generates active counteracting force with the same magnitude and opposite directions as the vibrating force of the ship main engine under the driving of pressure difference, so as to counteract the vibration of the main engine.
8. The method for actively damping vibration of a marine main engine based on dual-threshold discrimination according to claim 1, wherein the passive damping mode is entered when a system power terminal or a chip of the marine main engine fails and cannot output a signal.
9. The utility model provides a boats and ships host computer initiative damping device based on two threshold values are distinguished, installs between boats and ships host computer (8) and cabin lateral wall (10) through mounting base (17), its characterized in that includes: The sensor system is used for collecting vibration signals, collecting vibration signals of the ship host in real time and converting the vibration signals into electric signals; The integrated controller system is used for carrying out analog-to-digital conversion and digital band-pass filtering processing on the electric signals, separating out vibration frequency bands of host machine characteristics, and determining a vibration reduction mode for reducing vibration of the ship host machine by adopting a double-threshold hysteresis discrimination mechanism based on the vibration frequency bands; And the vibration reduction execution system is used for actively counteracting the vibration of the host machine.
10. The marine main engine active vibration damping device based on dual threshold discrimination according to claim 9, wherein the sensor system comprises an acceleration sensor (3) and a data transmission line (18); The integrated control system comprises an integrated controller (9), a data storage and processing unit (15), a numerical control unit (16) and a power supply module (20); The vibration reduction execution system comprises a hydraulic servo module (7), an oil reservoir (4), an oil inlet valve (11), a piston rod (1), a sealing ring (5), a damping force valve (6), a spiral spring (2), a connecting plate (19), a lubricating cylinder (12), an inner cylinder (13) and an outer cylinder (14).

Description

Ship main engine active vibration reduction method and device based on double-threshold discrimination Technical Field The invention relates to the technical field of ship turbine engineering, in particular to a ship main engine active vibration reduction method and device based on double-threshold discrimination. Background Marine main propulsion power plants typically employ high power, low speed diesel engines. The main engine generates huge periodic side thrust in the running process due to long stroke and large reciprocating motion mass. Such lateral forces excite the main body to produce complex transverse vibrations, which are mainly manifested as H-type and X-type vibration modes. If the control is not carried out effectively, the violent transverse vibration of the host machine can be transmitted to the ship body structure through the double-layer bottom, so that the harmful resonance of the superstructure is easily caused, the equipment failure and instrument failure of the cab are caused, and the working environment and the living comfort of crews are seriously affected. Long-term high-amplitude vibration can even cause structural damage such as fracture of a main machine body pull rod, loosening of a base bolt and the like, so that the navigation safety of the ship is endangered. At present, a passive supporting system is mainly adopted in engineering to restrain the transverse vibration of a host machine. Common forms include friction plate supports and hydraulic supports. The friction type support consumes vibration energy by utilizing friction damping, but the damping force is greatly influenced by pretightening force and friction coefficient, and the friction pair is worn in long-term operation, so that the gap is increased, the vibration reduction efficiency is attenuated with time, and the maintenance cost is high. The hydraulic support, while capable of providing a large stiffness, shifts the host frequency out of the resonance region, is still a passive control system in nature, with stiffness and damping parameters that are difficult to alter once set. However, in order for modern ships to meet environmental regulations such as EEDI, the modern ships often need to operate under off-design conditions, and the excitation frequency of the host becomes wide. Once the excitation frequency of the main engine falls into the natural frequency range of the hull structure in the speed change process, the conventional passive support system cannot provide an optimal vibration reduction effect due to the fact that parameters cannot be adjusted in real time, and even negative amplification effect can be generated at a specific frequency. For the problem that active vibration reduction is difficult to carry out under complex working conditions in the prior art, no effective solution is proposed at present. Disclosure of Invention The invention provides a ship main engine active vibration damping method and device based on double-threshold discrimination, which are used for solving the defect that the prior art is difficult to perform active vibration damping under complex working conditions. The invention provides a ship main engine active vibration damping method based on double-threshold discrimination, which comprises the following steps: Collecting vibration signals of a ship host in real time, and converting the vibration signals into electric signals, wherein the electric signals are voltage signals or charge signals; Performing analog-to-digital conversion and digital band-pass filtering processing on the electric signals to separate out vibration frequency bands of the host machine characteristics; Based on the vibration frequency band, a dual-threshold hysteresis judging mechanism is adopted to determine a vibration damping mode for damping the ship main engine, wherein the vibration damping mode comprises a passive vibration damping mode and an active vibration damping mode; When the active vibration reduction mode is started, the value of dynamic reverse acting force opposite to the vibration of the host machine is determined, and the vibration of the host machine is actively counteracted. According to the ship host active vibration damping method based on double-threshold discrimination, which is provided by the invention, the electric signal is subjected to analog-to-digital conversion and digital band-pass filtering treatment, and the vibration frequency band of host characteristics is separated, and the method comprises the following steps: Converting the electric signal into a high-precision digital signal by adopting Delta-Sigma analog-digital conversion logic, differential integral modulation and noise shaping technology; And separating out the vibration frequency band of the host computer characteristic through a digital band-pass filter on the basis of a linear time-invariant system, wherein the linearity of the linear time-invariant system meets the superposition and the second p