CN-122016953-A - Temperature-changing fitting-based rapid response control method and system for hydrogen in palladium-nickel oil

CN122016953ACN 122016953 ACN122016953 ACN 122016953ACN-122016953-A

Abstract

The invention belongs to the field of automatic control, and discloses a method and a system for controlling hydrogen quick response in palladium-nickel oil based on temperature change fitting, wherein the system comprises the steps of collecting oil sample characteristics and resistance values of Pd-Ni sensitive elements, and judging whether oil sample switching occurs or not; if the oil sample switching does not occur, calculating to obtain corrected resistance variation through a fitting algorithm, converting the corrected resistance variation into a hydrogen concentration value, if the oil sample switching occurs, performing temperature change control on the Pd-Ni sensitive element, and sequentially performing a transient temperature rise stage, a dynamic temperature regulation stage and a steady-state constant-temperature stage, constructing a resistance-temperature-time fitting model in the temperature change control process, analyzing and judging whether the resistance value after the steady-state constant-temperature stage is completed reaches a steady state based on the resistance-temperature-time fitting model, and if the resistance value reaches the steady state, correcting and converting the resistance value into the hydrogen concentration value. The invention solves the adapting problem of new oil samples with different viscosities and temperatures, and effectively eliminates the temperature drift and temperature change residual interference.

Inventors

LIU XIYIN
JIANG YACHAO
LI HUIQIANG
HUANG MING
XIA JIANGQIAO
HUANG WEIDONG
Fang Yunzheng
XIA XIN

Assignees

武汉豪迈光电科技有限公司

Dates

Publication Date: 20260512
Application Date: 20260407

Claims (10)

1. The method for controlling the rapid response of hydrogen in palladium-nickel oil based on temperature change fitting is characterized by comprising the following steps of: S1, monitoring and collecting oil sample characteristics and resistance values of Pd-Ni sensitive elements in real time, and judging whether oil sample switching occurs or not based on the oil sample characteristics and the resistance values, wherein the oil sample characteristics comprise oil sample temperature and oil sample viscosity; S2, if oil sample switching does not occur, acquiring the actual working temperature T w of the surface of the Pd-Ni sensitive element in real time, calculating to obtain corrected resistance variation through a fitting algorithm, and converting the corrected resistance variation into a hydrogen concentration value; s3, if oil sample switching occurs, recording the initial temperature and the initial viscosity of a new oil sample, triggering the temperature change control of the Pd-Ni sensitive element, and sequentially executing a transient temperature rise stage, a dynamic temperature regulation stage and a steady-state constant temperature stage; S4, synchronously collecting the resistance value and the actual working temperature in the temperature change control process, constructing a resistance-temperature-time fitting model based on the resistance value and the actual working temperature, analyzing and judging whether the resistance value reaches a steady state after finishing a steady state constant temperature stage based on the resistance-temperature-time fitting model, and correcting and converting the resistance value into a hydrogen concentration value and outputting the hydrogen concentration value if the resistance value reaches the steady state.
2. The method for controlling the rapid response of hydrogen in palladium-nickel oil based on temperature change fitting according to claim 1, wherein step S1 comprises: Monitoring and collecting the characteristics of an oil sample and the resistance value of a Pd-Ni sensitive element in real time, and calculating the resistance variation based on the resistance value; calculating the temperature change rate of the oil sample, the viscosity change rate of the oil sample and the mutation amplitude of the resistance value in the continuous preset time period according to the oil sample characteristics and the resistance value; After the preliminary early warning of oil sample switching is triggered, calculating the actual change quantity of the oil sample temperature and the actual change quantity of the oil sample viscosity in the preset time period before and after the preliminary early warning of oil sample switching is triggered, and confirming that the oil sample switching occurs when the actual change quantity of the oil sample temperature and the actual change quantity of the oil sample viscosity simultaneously accord with the preset change rule.
3. The method for controlling the rapid response of hydrogen in palladium-nickel oil based on temperature change fitting according to claim 2, wherein step S2 comprises: if the oil sample switching does not occur, acquiring the actual working temperature of the surface of the Pd-Ni sensitive element in real time, and comparing the actual working temperature with the steady-state temperature to ensure that the deviation of the actual working temperature and the steady-state temperature is within a preset deviation range; Based on the resistance value and the actual working temperature, dynamically correcting the resistance variation by adopting a fitting algorithm to obtain corrected resistance variation; and converting the corrected resistance change into a hydrogen concentration value through a preset concentration calibration formula.
4. The temperature-change fitting-based rapid hydrogen response control method in palladium-nickel oil according to claim 3, wherein the steady-state temperature acquisition method comprises: Extracting oil sample characteristics of the oil sample based on a current steady-state oil sample when oil sample switching does not occur, substituting the oil sample characteristics into a preset oil sample characteristic model, outputting a steady-state temperature adaptive to the oil sample based on the oil sample characteristic model, and fine-tuning the steady-state temperature every Z minutes according to the current acquired oil sample temperature, wherein the fine-tuning amplitude is +/-0.2 ℃, and Z is a positive integer.
5. The method for controlling the rapid response of hydrogen in palladium-nickel oil based on temperature change fitting according to claim 1, wherein the step S3 comprises: Immediately extracting the oil sample temperature and the oil sample viscosity at the moment of switching as the initial temperature and the initial viscosity of a new oil sample after oil sample switching; outputting the initial hydrogen molecular mass transfer rate of a new oil sample through a preset oil sample characteristic pre-judging model based on the initial temperature and the initial viscosity; determining a mass transfer rate interval of the initial hydrogen molecular mass transfer rate according to the initial hydrogen molecular mass transfer rate and a preset mass transfer rate interval dividing standard, and marking the current mass transfer interval as a current mass transfer interval, wherein the current mass transfer interval comprises a low-speed mass transfer interval, a medium-speed mass transfer interval and a high-speed mass transfer interval; Determining a target temperature of a transient heating stage according to the initial temperature, the initial viscosity, the initial hydrogen molecular mass transfer rate and a current mass transfer interval, marking the target temperature as a first target temperature, determining the heating rate of the transient heating stage based on the current mass transfer interval, determining a heat preservation time according to the initial viscosity and the current mass transfer interval, marking the heat preservation time as a first heat preservation time, and completing temperature change control of the transient heating stage based on the first target temperature, the heating rate and the first heat preservation time.
6. The temperature-change fitting-based rapid hydrogen response control method in palladium-nickel oil according to claim 5, wherein step S3 further comprises: After the transient temperature rising stage is finished, calculating the resistance change rate based on the resistance value at the end of the stage, adjusting the target temperature of the dynamic temperature regulating stage based on the resistance change rate and the current mass transfer interval, marking the target temperature as a second target temperature, determining the duration, the regulating frequency and the regulating amplitude of the dynamic temperature regulating stage according to the current mass transfer interval, and completing the temperature change control of the dynamic temperature regulating stage based on the second target temperature, the duration, the regulating frequency and the regulating amplitude; after the dynamic temperature regulation stage is finished, calculating the predicted resistance change rate of the resistance value through a temperature change fitting algorithm, judging whether the resistance value reaches a steady state according to the predicted resistance change rate, if so, entering a steady state constant temperature stage, and if not, reentering the dynamic temperature regulation stage until the resistance value reaches the steady state; Calculating the average value of the second target temperature of the dynamic temperature regulating stage, calculating the target temperature of the steady-state constant-temperature stage according to the average value of the second target temperature, the first target temperature and the current mass transfer interval, marking the target temperature as the optimal steady-state temperature, and controlling the temperature of the steady-state constant-temperature stage based on the optimal steady-state temperature.
7. The temperature-change fitting-based rapid hydrogen response control method in palladium-nickel oil according to claim 5, wherein step S3 further comprises: In the whole process of a transient temperature rising stage, a dynamic temperature regulating stage and a steady state temperature regulating stage, the real-time resistance change rate is calculated based on synchronously collecting the resistance values of Pd-Ni sensitive elements, the current hydrogen molecular mass transfer rate is reversely calculated according to the real-time resistance change rate and a preset association model, the current hydrogen molecular mass transfer rate is compared with the initial hydrogen molecular mass transfer rate, a deviation result is obtained, the deviation result comprises a deviation absolute value and a deviation direction, and the target temperature of the corresponding stage is dynamically corrected according to the deviation result.
8. The method for controlling hydrogen quick response in palladium-nickel oil based on temperature variation fitting according to claim 7, wherein the content of dynamically correcting the target temperature of the corresponding stage according to the deviation result comprises: when the absolute value of the deviation exceeds a preset deviation, dynamically correcting the target temperature of the corresponding stage according to the deviation direction; when the deviation direction is that the current hydrogen molecular mass transfer rate is reduced relative to the initial hydrogen molecular mass transfer rate, the target temperature of the corresponding stage is increased by 2-3%; The deviation direction is that when the current hydrogen molecular mass transfer rate is increased relative to the initial hydrogen molecular mass transfer rate, the target temperature of the corresponding stage is reduced by 2-3%; When the absolute value of the deviation does not exceed the preset deviation, the target temperature does not need to be corrected.
9. The method for controlling the rapid response of hydrogen in palladium-nickel oil based on temperature change fitting according to claim 1, wherein step S4 comprises: in the temperature change control process, synchronously collecting the resistance value and the actual working temperature, and constructing a three-dimensional data set consisting of the resistance value, the actual working temperature and the time; constructing a resistance-temperature-time fitting model based on the three-dimensional data set, and calculating to obtain a resistance predicted value set based on the resistance-temperature-time fitting model; Calculating the deviation between the resistance predicted value and the resistance value, marking the deviation as resistance deviation, judging whether the resistance value reaches a steady state or not based on the future resistance change rate, the resistance fluctuation amplitude and the resistance deviation, and locking the current resistance value to be taken as a steady state resistance value if the resistance value reaches the steady state; Calculating a steady-state resistance variable quantity based on the steady-state resistance value, correcting the steady-state resistance variable quantity to obtain a corrected steady-state resistance variable quantity, and converting the steady-state resistance variable quantity into a hydrogen concentration value based on the corrected steady-state resistance variable quantity.
10. The utility model provides a hydrogen quick response control system in palladium nickel oil based on alternating temperature fitting which characterized in that, the system includes: The oil sample switching judging module is used for monitoring and collecting oil sample characteristics and resistance values of the Pd-Ni sensitive element in real time, judging whether oil sample switching occurs or not based on the oil sample characteristics and the resistance values, wherein the oil sample characteristics comprise oil sample temperature and oil sample viscosity; The concentration first calculation module is used for collecting the actual working temperature T w of the surface of the Pd-Ni sensitive element in real time if oil sample switching does not occur, calculating the corrected resistance variation through a fitting algorithm, and converting the corrected resistance variation into a hydrogen concentration value; The temperature change control module is used for recording the initial temperature and the initial viscosity of a new oil sample if the oil sample is switched, triggering the temperature change control on the Pd-Ni sensitive element and sequentially executing a transient temperature rise stage, a dynamic temperature regulation stage and a steady state constant temperature stage; And the concentration second calculation module is used for synchronously collecting the resistance value and the actual working temperature in the temperature change control process, constructing a resistance-temperature-time fitting model based on the resistance value and the actual working temperature, analyzing and judging whether the resistance value reaches a steady state after finishing a steady state constant temperature stage based on the resistance-temperature-time fitting model, and correcting and converting the resistance value into a hydrogen concentration value and outputting the hydrogen concentration value if the resistance value reaches the steady state.

Description

Temperature-changing fitting-based rapid response control method and system for hydrogen in palladium-nickel oil Technical Field The invention relates to the field of automatic control, in particular to a method and a system for controlling hydrogen quick response in palladium-nickel oil based on temperature change fitting. Background Hydrogen is one of the key characteristic gases of early faults (such as partial discharge and corona) of oil immersed electrical equipment, and the rapid and accurate on-line monitoring of the concentration of the hydrogen is of great importance to equipment state assessment and fault early warning. Palladium-nickel (Pd-Ni) alloys are widely used as sensitive materials for dissolving hydrogen in oil due to their good selective adsorption and resistance change characteristics for hydrogen. However, in practical online monitoring applications, especially in the context of laboratory replacement of oil samples or field device oil circuit circulation renewal, existing Pd-Ni based sensors face a significant difficulty in that when the sensor is switched from one oil sample environment to another (or from air into oil), the sensor's response speed is significantly slowed down due to the high viscosity of the oil medium, the mass transfer resistance of hydrogen molecules at the oil-solid interface, and the possible oil film adsorption at the sensor surface, resulting in a longer "tailing" or "delay" phenomenon, which cannot meet the requirements of rapid diagnosis and real-time control. Conventional improvements have focused on optimizing the microstructure (e.g., porosification, nanocrystallization) of palladium-nickel materials or employing a single constant temperature heating mode. Constant temperature heating can accelerate the hydrogen desorption and mass transfer process to a certain extent, but has limited lifting effect. More critical is that the constant temperature mode of operation is passive, curing in the face of the dynamic transient of oil-sample switching. It is difficult to optimize the response speed, measurement sensitivity and long-term stability of the sensor at the same time with a fixed temperature set point. When a new oil sample, which may have different physical properties such as temperature, viscosity, etc., from an old oil sample, suddenly contacts the thermostatic sensor, the entire system (including the sensor chip, the surrounding oil film, and the solid-liquid interface) requires a longer time to reestablish the heat balance and mass exchange balance. This thermal relaxation and mass transfer relaxation process itself is the main source of response delay. The single constant temperature mode cannot actively accelerate the process, and the fixed temperature parameter may not even cope with the optimal solution of the specific oil sample characteristic, thereby limiting the further improvement of the response speed. Disclosure of Invention In order to overcome the defects in the prior art and achieve the purposes, the invention provides the following technical scheme: the invention provides a method for controlling hydrogen quick response in palladium-nickel oil based on temperature change fitting, which comprises the following steps: S1, monitoring and collecting oil sample characteristics and resistance values of Pd-Ni sensitive elements in real time, and judging whether oil sample switching occurs or not based on the oil sample characteristics and the resistance values, wherein the oil sample characteristics comprise oil sample temperature and oil sample viscosity; S2, if oil sample switching does not occur, acquiring the actual working temperature of the surface of the Pd-Ni sensitive element in real time, calculating to obtain corrected resistance variation through a fitting algorithm, and converting the corrected resistance variation into a hydrogen concentration value; s3, if oil sample switching occurs, recording the initial temperature and the initial viscosity of a new oil sample, triggering the temperature change control of the Pd-Ni sensitive element, and sequentially executing a transient temperature rise stage, a dynamic temperature regulation stage and a steady-state constant temperature stage; S4, synchronously collecting the resistance value and the actual working temperature in the temperature change control process, constructing a resistance-temperature-time fitting model based on the resistance value and the actual working temperature, analyzing and judging whether the resistance value reaches a steady state after finishing a steady state constant temperature stage based on the resistance-temperature-time fitting model, and correcting and converting the resistance value into a hydrogen concentration value and outputting the hydrogen concentration value if the resistance value reaches the steady state. Further, step S1 includes: Monitoring and collecting the characteristics of an oil sample and the resistance value of a Pd-Ni sensit