CN-122014724-A - Hydraulic power constant load control method for fatigue test of contact net compensation device

CN122014724ACN 122014724 ACN122014724 ACN 122014724ACN-122014724-A

Abstract

The invention relates to the technical field of simulation tests of parts of railway overhead line systems, in particular to a hydraulic power constant load control method for fatigue test of an overhead line system compensation device, which comprises the steps of integrating a pressure sensor on the end face of a piston of a hydraulic cylinder, wherein the end face is positioned in a rodless cavity of the hydraulic cylinder, and detecting the actual pressure of the end face by the pressure sensor in real time; the oil pump motor is characterized in that a proportional overflow valve is arranged in connection with an oil way of a hydraulic cylinder, a viscosity sensor is arranged in an oil tank to monitor the oil state, the opening degree of the proportional overflow valve is dynamically adjusted according to detection data of the pressure sensor, and the rotating speed of the oil pump motor is adjusted based on the opening degree adjusting result of the proportional overflow valve and the oil state data. According to the invention, through closed-loop control of the end face direct-measurement pressure and the rotation speed of the oil pump motor, the problem of unstable output load force is solved, uniform and stable movement is realized through accurate pressure control, the expansion and contraction of the contact net are truly simulated, meanwhile, the hydraulic impact is reduced through self-adaptive adjustment of the rotation speed of the oil pump, and the service life of key parts of the testing equipment is prolonged.

Inventors

XU LELE
ZHANG FULIN
JIANG WENJIE
KONG DEYANG
CHEN XINGYU
GUO RUIMENG
YIN BOZHENG
SU JIAHAO
JIANG KE
Zhu Mengdian

Assignees

中铁建电气化局集团轨道交通器材有限公司
中铁建电气化局集团试验检测有限公司常州分公司

Dates

Publication Date: 20260512
Application Date: 20260122

Claims (10)

1. The hydraulic power constant load control method for the fatigue test of the contact net compensation device is characterized by comprising the following steps of: Integrating a pressure sensor on the end face of a piston of a hydraulic cylinder, wherein the end face is positioned in a rodless cavity of the hydraulic cylinder, and the pressure sensor detects the actual pressure of the end face in real time; A proportional overflow valve is arranged in connection with an oil way of the hydraulic cylinder, and a viscosity sensor is arranged in an oil tank to monitor the oil state; dynamically adjusting the opening of the proportional overflow valve according to the detection data of the pressure sensor; and adjusting the rotating speed of the oil pump motor based on the opening degree adjusting result of the proportional relief valve and the oil liquid state data.
2. The hydraulic power constant load control method for fatigue testing of a catenary compensation device according to claim 1, wherein a wire harness of the pressure sensor is inserted into an axial passage inside a piston rod of the hydraulic cylinder and connected to a controller through a sealing joint provided at an end of the piston rod.
3. The hydraulic power constant load control method for fatigue test of a catenary compensation device according to claim 2, wherein the wire harness of the pressure sensor is a twisted pair shielded cable, and the shielding layer of the twisted pair shielded cable is grounded through the sealing joint.
4. The hydraulic power constant load control method for fatigue test of overhead line system compensation device according to claim 3, wherein the twisted pair shielded cable is connected to a signal conditioning module, and the signal conditioning module performs differential amplification and filtering processing on the pressure signal.
5. The hydraulic power constant load control method for fatigue test of overhead line system compensation device according to claim 3, wherein an elastic conductive bushing is arranged in the axial channel, and the inner wall of the elastic conductive bushing is in contact with the shielding layer of the twisted pair shielding cable; And a conductive magnetic layer is filled between the outer wall of the elastic conductive bushing and the inner wall of the axial channel.
6. The hydraulic power constant load control method for fatigue test of overhead line system compensation device according to claim 1, wherein adjusting the rotation speed of the oil pump motor based on the opening degree adjustment result of the proportional relief valve and the oil state data comprises: Dynamically generating a rotation speed correction coefficient alpha: and when alpha is smaller than a set threshold value, alpha takes the set threshold value; Wherein, the Is the relative deviation of the current viscosity of the oil from the reference viscosity, For the real-time opening of the proportional overflow valve, k 1 is a first weight coefficient, and k 2 is a second weight coefficient; Calculating a target rotation speed N of the oil pump: ; wherein N 0 is a preset reference rotation speed.
7. The hydraulic power constant load control method for fatigue testing of a catenary compensation device according to claim 6, wherein the first weight coefficient k 1 and the second weight coefficient k 2 are dynamically optimized by reinforcement learning, comprising: constructing a reward function according to the standard deviation of the pressure fluctuation and the unit test period energy consumption; the reward function is maximized by iteratively updating k 1 and k 2 in successive tests by the Q-learning algorithm.
8. The hydraulic power constant load control method for fatigue testing of a catenary compensation device according to claim 6, further comprising: When the opening degree of the proportional overflow valve is detected to be reduced, generating a forward compensation factor beta: ; Wherein, gamma is a compensation coefficient and is positively correlated with the opening degree reduction proportion; correcting the target rotation speed N: 。
9. The hydraulic power constant load control method for fatigue test of overhead line system compensator according to claim 6, wherein the target rotation speed performs safety limiting: setting a lower rotation speed threshold to 40% -60% of the rated rotation speed of the oil pump, and setting an upper rotation speed threshold to 105% -110% of the rated rotation speed of the oil pump; if the target rotating speed is lower than the rotating speed lower limit threshold, the actual output rotating speed takes the rotating speed lower limit threshold; if the target rotating speed is higher than the rotating speed upper limit threshold, the actual output rotating speed takes the rotating speed upper limit threshold; Otherwise, the actual output rotation speed is taken as the target rotation speed.
10. The hydraulic power constant load control method for fatigue testing of a catenary compensation device according to claim 6, further comprising extreme condition emergency switching; when the absolute value of the real-time opening change rate of the proportional overflow valve exceeds 25%/s-35%/s, and More than 10% -30%; And suspending calculation of the rotation speed correction coefficient alpha, and controlling the oil pump motor to switch to safe rotation speed operation, wherein the safe rotation speed is 60% -70% of the rated rotation speed of the oil pump.

Description

Hydraulic power constant load control method for fatigue test of contact net compensation device Technical Field The invention relates to the technical field of simulation tests of parts of railway overhead contact systems, in particular to a hydraulic power constant load control method for fatigue test of overhead contact system compensation devices. Background In the field of rail transit, fatigue testing of contact net compensation devices is critical to ensuring equipment reliability. In the prior art, a hydraulic cylinder is often used as a test power source to drive a load structure to reciprocate up and down so as to meet the test requirement of a contact net compensation device. In the testing process, the hydraulic cylinder is influenced by oil temperature change, internal leakage and friction resistance, output load force is unstable, test data is distorted, meanwhile, under a typical low-speed working condition, the hydraulic cylinder is easy to generate displacement setback, motion smoothness is damaged, and the fatigue life of the compensation device cannot be accurately estimated under the conditions. Disclosure of Invention The invention provides a hydraulic power constant load control method for fatigue test of a contact net compensation device, which can effectively solve the problems in the background technology. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: A hydraulic power constant load control method for fatigue test of a contact net compensation device comprises the following steps: Integrating a pressure sensor on the end face of a piston of a hydraulic cylinder, wherein the end face is positioned in a rodless cavity of the hydraulic cylinder, and the pressure sensor detects the actual pressure of the end face in real time; A proportional overflow valve is arranged in connection with an oil way of the hydraulic cylinder, and a viscosity sensor is arranged in an oil tank to monitor the oil state; dynamically adjusting the opening of the proportional overflow valve according to the detection data of the pressure sensor; and adjusting the rotating speed of the oil pump motor based on the opening degree adjusting result of the proportional relief valve and the oil liquid state data. Further, the wire harness of the pressure sensor penetrates through an axial channel in the piston rod of the hydraulic cylinder and is connected to the controller through a sealing joint arranged at the end part of the piston rod. Further, the wire harness of the pressure sensor is a twisted pair shielded cable, and the shielding layer of the twisted pair shielded cable is grounded through the sealing joint. Further, the twisted pair shielded cable is connected to a signal conditioning module that performs differential amplification and filtering processing on the pressure signal. Further, an elastic conductive bushing is arranged in the axial channel, and the inner wall of the elastic conductive bushing is in contact with the shielding layer of the twisted pair shielding cable; And a conductive magnetic layer is filled between the outer wall of the elastic conductive bushing and the inner wall of the axial channel. Further, based on the opening adjustment result of the proportional relief valve and the oil liquid state data, adjusting the rotation speed of the oil pump motor includes: Dynamically generating a rotation speed correction coefficient alpha: and when alpha is smaller than a set threshold value, alpha takes the set threshold value; Wherein, the Is the relative deviation of the current viscosity of the oil from the reference viscosity,For the real-time opening of the proportional overflow valve, k 1 is a first weight coefficient, and k 2 is a second weight coefficient; Calculating a target rotation speed N of the oil pump: ; wherein N 0 is a preset reference rotation speed. Further, the first weight coefficient k 1 and the second weight coefficient k 2 are dynamically optimized by reinforcement learning, including: constructing a reward function according to the standard deviation of the pressure fluctuation and the unit test period energy consumption; the reward function is maximized by iteratively updating k 1 and k 2 in successive tests by the Q-learning algorithm. Further, the method further comprises the following steps: When the opening degree of the proportional overflow valve is detected to be reduced, generating a forward compensation factor beta: ; Wherein, gamma is a compensation coefficient and is positively correlated with the opening degree reduction proportion; correcting the target rotation speed N: 。 further, the target rotational speed performs a safety limiter: setting a lower rotation speed threshold to 40% -60% of the rated rotation speed of the oil pump, and setting an upper rotation speed threshold to 105% -110% of the rated rotation speed of the oil pump; if the target rotating speed is lower than the rotating speed lo