Liquefied petroleum gas management system based on cloud platform

Abstract

The invention relates to the technical field of LPG storage safe transportation and automatic control, in particular to a liquefied petroleum gas management system based on a cloud platform. The system comprises a state sensing module, a dynamic starting frequency resolving module, a safety attenuation factor generation module and an instruction frequency generation module. The system acquires the pressure of the storage tank and the tank car in real time and calculates the dynamic pressure difference to determine the minimum safe starting frequency; after the flow velocity is stable, a final instruction frequency is generated and output in combination with a safety attenuation factor calculated by pipeline electrostatic charges; according to the invention, the conversion from fixed frequency starting to dynamic intelligent starting is realized, and the problem of starting failure or pump body damage caused by fixed starting frequency is effectively solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of liquefied petroleum gas (LPG) storage safety transfer and automatic control, in particular to a liquefied petroleum gas management system based on a cloud platform. BACKGROUND

[0002] In the management of liquefied petroleum gas transfer, the pump control strategy faces many challenges; the traditional starting mode mostly adopts fixed frequency; however, the real-time pressure difference between the storage tank and the tank truck is dynamically changing; when the starting pressure difference is too high, the fixed frequency cannot provide enough torque, which easily leads to starting failure or pump body damage; in the stable transfer stage, LPG flow is easy to produce pipeline static charge, which brings serious safety hazards; in order to avoid risks, the existing technology generally adopts fixed speed limiting strategy, for example, the flow rate is strictly limited below the safety threshold; such rigid fixed frequency starting and fixed speed limiting operation strategy not only leads to low starting success rate and equipment safety problems, but also seriously restricts the transfer efficiency, forming a rigid contradiction between safety and efficiency; therefore, how to solve the high pressure difference starting problem and realize the dynamic balance between static electricity safety and transfer efficiency is a technical problem urgently to be solved in the field. SUMMARY

[0003] To solve the above technical problems, the present application provides a liquefied petroleum gas management system based on a cloud platform, in particular, the technical scheme of the present application comprises: A state perception module is used to collect the storage tank pressure in real time; The state perception module is also used to collect the real-time pressure of the tank truck; The state perception module is also used to collect the real-time flow rate of the pipeline; The state perception module is also used to collect the pipeline static charge; A dynamic starting frequency solving module is used to calculate the dynamic pressure difference according to the storage tank pressure and the real-time pressure of the tank truck collected by the state perception module; and combine the dynamic pressure difference with the preset pump body characteristic parameters to solve the starting torque demand index for representing overcoming the back pressure load; and then determine the minimum safe starting frequency according to the starting torque demand index and the preset minimum safe operation frequency; A safety attenuation factor generation module is used to dynamically calculate the safety attenuation factor according to the pipeline static charge collected by the state perception module, and refer to the preset static electricity warning threshold and the preset static electricity tripping threshold; An instruction frequency generation module is used to output the minimum safe starting frequency determined by the dynamic starting frequency solving module as the instruction frequency in the starting stage; and after monitoring that the real-time flow rate of the pipeline is stable, switch to the stable transfer stage, generate and output the final instruction frequency according to the preset economic optimization frequency and the safety attenuation factor calculated by the safety attenuation factor generation module.

[0004] Preferably, the dynamic start-up frequency solving module solves the start-up torque demand index, specifically for: multiplying the dynamic pressure difference by a preset pressure torque conversion coefficient to obtain a static pressure backload; and adding the static pressure backload to a preset fixed friction torque to generate the start-up torque demand index.

[0005] Preferably, the dynamic start-up frequency solving module determines the minimum safe start-up frequency, specifically including: calculating a demand frequency according to the start-up torque demand index and a preset torque frequency calibration coefficient; comparing the demand frequency with the preset minimum safe running frequency; taking the larger value of the demand frequency and the preset minimum safe running frequency as the minimum safe start-up frequency.

[0006] Preferably, the instruction frequency generating module monitors that the pipeline real-time flow rate is stable, specifically including: when it is monitored that the pipeline real-time flow rate is stable near a preset first safety threshold and the duration exceeds a preset stable time threshold, it is determined that the system enters a stable transmission stage.

[0007] Preferably, the safety attenuation factor generating module dynamically calculates the safety attenuation factor, specifically including: when the pipeline static electricity charge is lower than the static electricity warning threshold, the safety attenuation factor is determined as 1; when the pipeline static electricity charge is not lower than the static electricity warning threshold and is lower than the static electricity tripping threshold, the safety attenuation factor is calculated according to the normalized intrusion depth of the pipeline static electricity charge between the static electricity warning threshold and the static electricity tripping threshold, and combined with a preset attenuation coefficient; when the pipeline static electricity charge is not lower than the static electricity tripping threshold, the safety attenuation factor is determined as 0.

[0008] Preferably, the safety attenuation factor generating module calculates the safety attenuation factor, specifically including: dividing the difference between the pipeline static electricity charge and the static electricity warning threshold by the difference between the static electricity tripping threshold and the static electricity warning threshold to obtain the normalized intrusion depth; multiplying the normalized intrusion depth by the preset attenuation coefficient to obtain an attenuation amount; subtracting the attenuation amount from 1 to obtain an intermediate result; and taking the larger value of the intermediate result and 0 to obtain the safety attenuation factor.

[0009] Preferably, the instruction frequency generation module generates the final instruction frequency, specifically comprising: The preset economic optimization frequency is multiplied by the safety attenuation factor calculated by the safety attenuation factor generation module to obtain the final instruction frequency.

[0010] Preferably, the state sensing module is further used to collect the tank truck grounding state. The instruction frequency generation module is further used to output the minimum safety start frequency or the final instruction frequency only when the tank truck grounding state collected by the state sensing module is valid grounding.

[0011] Compared with the prior art, the present application has the following beneficial effects: 1. The present system dynamically determines a just-right minimum safety start frequency by real-time sensing the dynamic pressure difference between the storage tank and the tank truck, solving the start torque required to overcome the current back pressure load, and combining the minimum safety running frequency of the pump body; this abandons the rigid strategy of traditional fixed frequency start, can guarantee sufficient torque to successfully start under high pressure difference conditions, and can ensure that the frequency is not lower than the safety lower limit, effectively solving the problems of start failure or pump damage caused by fixed start frequency; 2. In the stable conveying stage, the present system dynamically calculates a safety attenuation factor by real-time monitoring of the pipeline static electricity level and referring to the preset static electricity warning threshold and tripping threshold; the factor is multiplied by the preset economic optimization frequency to generate the final instruction frequency; this constructs a static electricity-flow rate closed loop negative feedback system: when the static electricity is safe, the system runs at the highest efficiency, breaking through the efficiency bottleneck of traditional fixed speed limit; when the static electricity accumulates, the system automatically and smoothly reduces the frequency to actively suppress the static electricity, achieving dynamic balance between safety and efficiency; 3. The present system provides a complete two-stage control strategy and realizes automatic smooth switching between the two stages; the system executes the dynamic safety start strategy and automatically switches to the stable conveying strategy with static electricity safety as the constraint and economic optimization as the target after monitoring that the pipeline flow rate is stable; this architecture decouples and optimizes the start safety, running safety and running efficiency, and systematically solves the rigid contradiction between the start problem and the safety and efficiency in running in the industry; 4. The present system also includes the tank truck grounding state in the control logic and takes it as the highest priority safety precondition for system running; the instruction frequency generation module only allows to output the start frequency or the running frequency when valid grounding of the tank truck is monitored, otherwise forced shutdown; this adds a key physical safety interlock in line with industry specifications, ensures that all dynamic algorithms are executed under the premise of basic grounding safety, and makes the safety of the entire system more complete and the reliability higher. BRIEF DESCRIPTION OF DRAWINGS

[0012] The application will be further explained in connection with the accompanying drawings and embodiments: Figure 1 is a structural diagram of the system of the application. DETAILED DESCRIPTION

[0013] In order to make the objectives, technical solutions and advantages of the application clearer, the application will be further described in detail below with reference to specific embodiments.

[0014] Embodiment 1 Please refer to Figure 1 A liquefied petroleum gas management system based on a cloud platform, comprising: A state sensing module for collecting real-time tank pressure; The state sensing module is also used to collect real-time tank truck pressure; The state sensing module is also used to collect real-time pipeline flow rate; The state sensing module is also used to collect pipeline static electricity; A dynamic start frequency solving module for calculating a dynamic pressure difference based on the tank pressure and the real-time tank truck pressure collected by the state sensing module, and combining the dynamic pressure difference with preset pump body characteristic parameters to solve a start torque demand index for representing the load of overcoming back pressure, and then determining a minimum safe start frequency based on the start torque demand index and a preset minimum safe operation frequency; A safety attenuation factor generating module for dynamically calculating a safety attenuation factor based on the pipeline static electricity collected by the state sensing module, and referring to a preset static electricity warning threshold and a preset static electricity tripping threshold; An instruction frequency generating module for outputting the minimum safe start frequency determined by the dynamic start frequency solving module as an instruction frequency in the start phase, and switching to a stable transmission phase after detecting that the real-time pipeline flow rate is stable, and generating and outputting a final instruction frequency based on a preset economic optimization frequency and the safety attenuation factor calculated by the safety attenuation factor generating module.

[0015] A liquefied petroleum gas management system based on a cloud platform, comprising: a state sensing module, a dynamic start frequency solving module, a safety attenuation factor generating module and an instruction frequency generating module; In this embodiment, the system is deployed in the DCS or PLC control layer of the LPG warehouse, and data monitoring and model optimization are performed through the cloud platform; The state sensing module aims to provide real-time and high-precision field data input for subsequent dynamic solving and closed-loop control; in this embodiment, it specifically includes but is not limited to: A pressure transmitter installed on the LPG tank for collecting real-time tank pressure, denoted as in this embodiment; The pressure transmitter installed on the loading arm is used to collect the real-time pressure of the tanker truck, and is denoted as [insert denotion here] in this embodiment. ; An electromagnetic flow meter or turbine flow meter installed on the loading arm is used to collect real-time flow velocity in the pipeline, denoted as [insert flow meter name here] in this embodiment. ; An electrostatic sensor installed at a critical location on the loading arm is used to collect the static charge in the pipeline in real time; in this embodiment, it is denoted as... ; All these real-time measurements are sent to the control core at high frequency for processing; The core purpose of the dynamic start-up frequency calculation module is to abandon the rigid strategy of fixed-frequency start-up in existing technologies, and instead dynamically calculate a suitable start-up frequency based on the real-time system back pressure to solve the problems of start-up failure and pump stalling damage under high pressure differential. The specific working logic of this module is as follows: This module is based on data collected by the state awareness module. and Calculate the real-time dynamic pressure difference This calculation follows the basic principles of fluid mechanics:

[0016] Among them, the The value accurately quantifies the actual back pressure that the LPG pump body needs to overcome at the moment of startup, and is a key input for subsequent torque calculation. This module combines Based on preset pump body characteristic parameters, a starting torque demand index defined in this invention is calculated to characterize the overcoming back pressure load; this index is an intermediate quantity that establishes the relationship between two different physical domains: pressure and frequency. This module determines the minimum safe starting frequency based on the starting torque demand index and the preset minimum safe operating frequency. ;Should This is the core output instruction during the startup phase of this invention; The safety attenuation factor generation module aims to quantify the abstract electrostatic safety state into a standardized correction factor that can be used for control calculations, and is the core technology for realizing active safety closed-loop control. This module is based on the static charge in the pipeline collected by the state sensing module. And refer to the preset electrostatic warning threshold. With the preset electrostatic trip threshold Dynamically calculate the safety attenuation factor ; Qwarn refers to the electrostatic safety warning limit, and Qtrip refers to the electrostatic safety trip limit; both threshold values are safety parameters preset according to industry safety specifications and field conditions; The is a dimensionless value between [0, 1], represents safety, represents triggering shutdown; it will serve as a safety limiting factor for the modulation frequency of the high-efficiency delivery stage; The instruction frequency generation module is the final execution unit of the two-stage control strategy of the application, responsible for outputting the final operating frequency instruction to the frequency converter VFD according to the safety and efficiency targets of different stages; The control logic of the module is divided into two stages: Start-up stage: after receiving the start-up instruction, the module will output the minimum safe start-up frequency determined by the dynamic start-up frequency calculation module to the VFD as the instruction frequency ; Stage switching: during the operation of stage one, the module continuously monitors the real-time flow rate of the pipeline from the state perception module ; after monitoring that is stable, it is determined that the system has been stabilized and pressurized, and automatically switches to the stable delivery stage; Stable delivery stage: in this stage, the control target of the module changes to efficiency priority and safety guarantee; it generates and outputs the final instruction frequency according to the pre-set economic optimization frequency and the safety attenuation factor calculated by the safety attenuation factor generation module ; fopt refers to the ideal highest efficiency operating frequency; the value is a constant value preset offline according to the system pipeline characteristics and LPG properties, and the corresponding flow rate can break through the industry limit of 3m / s; for example, by establishing a mapping model of pump body efficiency-frequency-pressure difference, combined with the pipe network hydraulic model, the energy consumption per unit LPG delivery is optimized as the optimization target, and the value is obtained by numerical optimization algorithm; ; Through the cooperative work of the above modules, the application provides a complete and adaptive two-stage control system; it discards the rigid strategy of fixed speed limit, solves the problems of high-pressure difference start-up failure and pump body damage in the start-up stage through the dynamic start-up frequency calculation module; in the stable delivery stage, the safety attenuation factor generation module and the instruction frequency generation module are matched to build a closed-loop feedback of electrostatic flow rate; this architecture successfully decouples and optimizes the start-up safety, operation safety and operation efficiency, and provides a complete system architecture basis for solving the rigid contradiction between efficiency and safety in the industry. ​

[0017] Example 2: The dynamic start frequency calculation module calculates the start torque demand index, specifically used for: The static pressure back load is obtained by multiplying the dynamic pressure difference by the preset pressure-torque conversion coefficient. The static pressure back load is then added to the preset fixed friction torque to generate the starting torque demand index.

[0018] According to the system of Embodiment 1, the dynamic start frequency calculation module calculates the start torque demand index, specifically by: multiplying the dynamic pressure difference with a preset pressure-torque conversion coefficient to obtain the static pressure back load; and adding the static pressure back load with a preset fixed friction torque to generate the start torque demand index. As a further refinement of Example 1, this example details how the dynamic start frequency calculation module calculates the start torque demand index. The specific method; its purpose is to establish a physical model that can accurately reflect the real-time load, as an intermediate quantity connecting the two different physical domains of dynamic differential pressure and start-up frequency; In this embodiment, the solution follows an original load superposition model; this model assumes that the total load that needs to be overcome when the VFD starts is... It mainly comes from two parts: one is real-time dynamic differential pressure. The static pressure back load formed on the pump impeller is one of the two factors: fluid viscosity and constant frictional load generated by the mechanical seal. Starting torque demand index The calculation formula is:

[0019] in, Physical meaning: Real-time dynamic pressure difference; Source: from Example 1 Calculated; The physical meaning of this is the preset pressure-torque conversion coefficient; its source is an inherent characteristic parameter of the pump body obtained through calibration of the LPG pump characteristic curve and load test; its physical meaning is the equivalent volumetric torque coefficient, used to convert pressure... Converted to torque hydrostatic back load; Specifically, this parameter can be obtained Subsequently, multiple load start-up tests were conducted under different but constant dynamic pressure differentials, and the total torque required for the pump to start precisely was recorded. Then use the least squares method to... The relationship was obtained by linear regression fitting. The physical meaning is the preset fixed friction torque; the source is an inherent characteristic parameter of the pump body obtained by calibrating the LPG pump through no-load start-up test, representing the constant friction load generated by fluid viscosity and mechanical seal. Specifically, this parameter can be calibrated by performing an no-load start test on the LPG pump and recording the minimum VFD output torque at the moment of start-up. The calculation logic of this module is as follows: Dynamic pressure difference With preset pressure-torque conversion coefficient Multiply to obtain the dynamically changing static back load. ; The static pressure back load is compared with a preset fixed friction torque. Add them together to generate the total starting torque demand index. ; This embodiment defines... The original physical model, for the first time, incorporates external perturbation variables. The problem was transformed into a control input; this allowed the output of the dynamic start-up frequency calculation module to no longer be a blind, fixed value, but rather to have a precise, real-time basis for the physical load; this laid the foundation for subsequent... The accurate solution laid a solid foundation and provided the core mathematical model for solving the problem of failure upon startup.

[0020] Example 3: The dynamic startup frequency calculation module determines the minimum safe startup frequency, specifically including: The required frequency is calculated based on the starting torque demand index and the preset torque frequency calibration coefficient; Compare the required frequency with the preset minimum safe operating frequency; The larger value between the required frequency and the preset minimum safe operating frequency is taken as the minimum safe start frequency.

[0021] According to the system in Embodiment 1, the dynamic start frequency calculation module determines the minimum safe start frequency, specifically including: calculating the required frequency based on the start torque demand index and the preset torque frequency calibration coefficient; comparing the required frequency with the preset minimum safe operating frequency; and taking the larger value between the required frequency and the preset minimum safe operating frequency as the minimum safe start frequency. As a further refinement of Embodiment 1, this embodiment details how the dynamic startup frequency calculation module determines the minimum safe startup frequency. The specific method; its purpose is to utilize the solution obtained in Example 2 The VFD frequency that can provide the torque is calculated in reverse, and at the same time, the frequency is forced to meet the pump body's minimum safety requirements to avoid pump blockage and damage. Minimum safe startup frequency The calculation formula is:

[0022] in, The physical meaning of 15Hz is the minimum safe operating frequency preset. This is a core specification parameter provided by the LPG pump manufacturer, representing the minimum speed that must be maintained to prevent cavitation, severe vibration, and seal damage in the pump body. The physical meaning of the starting torque demand index is derived from the formula in Example 2. The physical meaning is the preset torque frequency calibration coefficient; the source is a VFD characteristic coefficient obtained by calibrating it through a load test with an LPG pump using a VFD, which is used to correlate the output torque with the operating frequency. Specifically, this coefficient Multiple start-up tests under different loads can be performed using a VFD with an LPG pump, and the frequency of the exact start-up can be recorded. And through regression analysis, such as fitting The relationship is determined; The calculation logic of this module is as follows: Based on the starting torque demand index With the preset torque frequency calibration coefficient Calculate the demand frequency ,in This step is based on the V / f control theory of VFD, and its purpose is to calculate the V / f control that can just provide... The required VFD frequency for torque; Demand frequency With the preset minimum safe operating frequency Compare; Take the required frequency With the preset minimum safe operating frequency The larger value in The function serves as the final minimum safe startup frequency. ; This embodiment The function design provides a double-protected gain effect: Ensure successful startup: This ensured Always sufficient to overcome high It provides sufficient starting torque, ensuring a 100% start-up success rate and solving the problem of failure upon startup; Ensure pump body safety: This ensured Even under any working conditions Extremely low, resulting in The frequency will never fall below the pump body's safety limit; this avoids pump blockage damage caused by excessively low frequency. This solution addresses two major industry challenges: startup failure and pump damage.

[0023] Example 4: The command frequency generation module detected that the real-time flow velocity in the pipeline was stable, specifically including: When the real-time flow rate in the pipeline is monitored to be stable near a preset first safety threshold and the duration exceeds a preset stabilization time threshold, the system is determined to have entered the stable output stage.

[0024] According to the system of Embodiment 1, the command frequency generation module detects that the real-time flow velocity of the pipeline is stable, specifically including: when the real-time flow velocity of the pipeline is detected to be stable near a preset first safety threshold and the duration exceeds a preset stable time threshold, the system is determined to enter the stable output stage. As a further refinement of Embodiment 1, this embodiment details how the command frequency generation module monitors the real-time flow velocity in the pipeline. The stable and specific judgment logic aims to provide a clear and reliable triggering condition for the system to automatically and smoothly switch from the safe startup phase to the high-efficiency transfer phase. In this embodiment, the instruction frequency generation module continuously monitors... The system is considered to have entered a stable transmission phase when both of the following conditions are met simultaneously: When the real-time flow rate of the pipeline is monitored At the preset first safety threshold The surrounding area is stable; Furthermore, the duration of this stable state exceeds the preset stability time threshold. ; in, Physical meaning: The preset first safety threshold; Source: This is a pre-set flow rate value, for example, 1.4 m / s; This value is a safe start-up flow rate set through experimental calibration or based on fluid dynamics simulation to ensure stable pressure build-up in the pipeline during the start-up phase and that it is far below the electrostatic safety threshold; Monitoring Stable conditions in the vicinity indicate that the startup was successful and the pipeline has been initially pressurized; The physical meaning is a preset stabilization time threshold; its source is an adjustable tuning parameter, for example, it can be set to 5 seconds; its purpose is to filter out instantaneous fluctuations in flow rate, ensuring that the system has truly entered a stable pressure build-up state, rather than instantaneous pulses; in actual calibration, The value should be significantly lower than The corresponding flow rate, but it must be higher than that of the pump body. The lowest stable flow rate that can be achieved at the specified frequency to ensure a smooth switching process; The value of must be greater than the flow rate oscillation period during the system startup phase to ensure robust switching and avoid misjudgment; Once this condition is triggered, the instruction frequency generation module will execute a phase switching action, changing the VFD's target frequency from... Smoothly increase the slope according to the preset frequency climb rate to... And simultaneously activate based on Dynamic security restrictions; This embodiment uses clearly defined stage switching logic. and This ensures the orderly connection of system control strategies; it guarantees that the system can only relinquish control and transition to the high-efficiency Phase Two after successful startup and stable pipeline pressure have been confirmed; this avoids sudden changes in control strategies and system oscillations caused by switching to high frequency before startup is stable, and greatly improves the stability and safety of the entire process.

[0025] Example 5: The safety attenuation factor generation module dynamically calculates the safety attenuation factor, specifically including: When the static charge in the pipeline is below the electrostatic warning threshold, the safety attenuation factor is set to 1. When the static charge in the pipeline is not lower than the electrostatic warning threshold and is lower than the electrostatic trip threshold, the safety attenuation factor is calculated based on the normalized intrusion depth of the static charge in the pipeline between the electrostatic warning threshold and the electrostatic trip threshold, combined with the preset attenuation coefficient. When the static charge in the pipeline is not lower than the electrostatic trip threshold, the safety attenuation factor is set to 0.

[0026] According to the system of Embodiment 1, the safety attenuation factor generation module dynamically calculates the safety attenuation factor, specifically including: when the static charge on the pipeline is lower than the electrostatic warning threshold, the safety attenuation factor is determined to be 1; when the static charge on the pipeline is not lower than the electrostatic warning threshold and is lower than the electrostatic trip threshold, the safety attenuation factor is calculated based on the normalized intrusion depth of the static charge on the pipeline between the electrostatic warning threshold and the electrostatic trip threshold, and in combination with a preset attenuation coefficient; when the static charge on the pipeline is not lower than the electrostatic trip threshold, the safety attenuation factor is determined to be 0. The safety attenuation factor generation module calculates the safety attenuation factor, specifically including: dividing the difference between the pipeline static charge and the electrostatic warning threshold by the difference between the electrostatic trip threshold and the electrostatic warning threshold to obtain the normalized intrusion depth; multiplying the normalized intrusion depth by the preset attenuation coefficient to obtain the attenuation amount; subtracting the attenuation amount from 1 to obtain an intermediate result; and taking the larger value between the intermediate result and 0 to obtain the safety attenuation factor. As a further refinement of Example 1, this example details the dynamic calculation of the safety attenuation factor by the safety attenuation factor generation module. The invention presents an original segmented security model; specifies the detailed calculation method for the warning zone in the model; and defines the core algorithm for dynamic security restrictions. Its purpose is to ensure electrostatic safety. Divided into three distinct, non-linear control regions, and through The calculation transforms the relationship between safety and efficiency from one of opposition to one of dynamic coupling, which is the core technological guarantee that allows this invention to break through the 3m / s limit. In this embodiment, The calculation of is a piecewise function, and its mathematical expression is as follows: when hour, ; when hour, ; when hour, ; in, Physical meaning: Real-time measurement of static charge in the pipeline; Source: Status sensing module; Physical meaning: preset electrostatic warning threshold; Source: preset safety parameters; The physical meaning is the preset electrostatic tripping threshold; the source is the preset safety parameters, and... ; : Physically, it refers to the preset attenuation coefficient; the source is an adjustable tuning parameter used to adjust the sensitivity of attenuation, which is usually set. This parameter can be tuned during on-site commissioning, for example, in... near At that time, by gradually increasing Value, observation The descent slope and the final The stability point is determined to achieve the best balance between the safety margin of electrostatic suppression and the transfer efficiency. The larger the value, the more sensitive the decay and the higher the safety margin, but it may sacrifice too much efficiency; The logical explanation of this model is as follows: Safe zone: When the pipe is statically charged Below the electrostatic warning threshold When the static electricity level is low, the system is in a safe zone; at this time, the safety attenuation factor is... The value is set to 1; Trip zone: When the pipeline is charged with static electricity Not lower than, i.e., greater than or equal to, the electrostatic discharge trip threshold When the static electricity level reaches the safety threshold, the safety attenuation factor will be adjusted accordingly. The value is determined to be 0; Warning zone: When the pipeline has static charge Not lower than the electrostatic warning threshold And below the electrostatic discharge trip threshold At this point, the system enters the active safety adjustment zone; at this time, the module determines the normalized intrusion depth of the pipeline static charge between the electrostatic warning threshold and the electrostatic trip threshold, and combines this with a preset attenuation coefficient. Calculate the safety attenuation factor; The calculation process is broken down into: static charge in the pipe With electrostatic warning threshold The difference, divided by the electrostatic trip threshold. With electrostatic warning threshold The difference, i.e., the calculation This value is a dimensionless number in the range [0,1), representing... Depth of intrusion within the warning zone; Normalized penetration depth and preset attenuation coefficient Multiply to obtain the attenuation, i.e. ; Subtracting the attenuation from 1 yields an intermediate result, i.e. ; And take the larger value between the intermediate result and 0. The function obtains the final safety attenuation factor. ; This embodiment collectively defines a refined, non-linear safety-efficiency conversion model; it abandons the one-size-fits-all static speed limit and achieves active safety: In the safe zone The system does not sacrifice any efficiency, allowing VFD to run at full speed. ; Within the restricted area, The value will change The rise and smooth fall constitute a strong closed-loop negative feedback. Lift drop drop drop The rate of decrease is generated, and static electricity is actively suppressed within a safe threshold. the following; The design ensures The value will never drop to a negative number under any circumstances, ensuring the robustness and safety of the control output.

[0027] Example 6: The instruction frequency generation module generates the final instruction frequency, specifically including: The final command frequency is obtained by multiplying the preset economic optimization frequency by the safety attenuation factor calculated by the safety attenuation factor generation module.

[0028] According to the system of Embodiment 1, the command frequency generation module generates the final command frequency, specifically by multiplying the preset economic optimization frequency by the safety attenuation factor calculated by the safety attenuation factor generation module to obtain the final command frequency; As a further refinement of Embodiment 1, this embodiment details how the instruction frequency generation module generates the final instruction frequency during the stable transfer phase. The specific method; its purpose is to dynamically couple the ideal efficiency target with the real-time security state, which is the final execution formula of the closed-loop high-efficiency transfer module of this invention; Throughout Phase Two, the final instruction frequency of VFD... Refresh frequently using the following formula:

[0029] in, The physical meaning is the preset economic optimization frequency; the source is a preset constant value, representing the ideal maximum efficiency. Physical meaning: Safety attenuation factor; calculated in real time by the safety attenuation factor generation module; The calculation logic of this module is as follows: The preset economic optimization frequency The safety attenuation factor calculated by the safety attenuation factor generation module Multiply to obtain the final instruction frequency. ; This embodiment is the core of achieving efficiency adaptive to the safety boundary; it transforms the static opposition between safety and efficiency into a dynamic coupling: When safe , The system operates efficiently at a flow rate exceeding 3 m / s; When static electricity accumulates , Actively and smoothly lowered The flow rate decreases accordingly, actively suppressing the generation of static electricity; This formula is the ultimate technical solution of this invention, achieving both active safety and maximum efficiency.

[0030] Example 7: The status sensing module is also used to collect the grounding status of the tanker truck; The command frequency generation module is also used to output the minimum safe start frequency or the final command frequency only when the tanker grounding status collected by the status sensing module is validly grounded.

[0031] According to the system of Embodiment 1, the state sensing module is also used to collect the grounding status of the tank truck; the command frequency generation module is also used to output the minimum safe start frequency or the final command frequency only when the grounding status of the tank truck collected by the state sensing module is a valid ground. As a further refinement of Embodiment 1, this embodiment adds a key safety prerequisite to enhance the overall safety of the system; its purpose is to ensure that the high-risk operation of LPG loading can only be started and carried out on the basis of effective grounding protection, in accordance with the highest industry safety standards. In this embodiment: In addition to collecting pressure, flow rate, and electrostatic signals, the status sensing module is also used to collect the grounding status of the tank truck. ; Physical meaning: Connection status of the tank truck grounding clamp; Source: Switch signal from the tank truck grounding clamp, for example, True represents effective grounding, False represents no grounding or poor grounding; Accordingly, the instruction frequency generation module adds a highest-priority safety interlock when executing its output logic; this module only activates when the tanker grounding status is collected by the state awareness module. For example, when effectively grounded Only then is a non-zero output frequency allowed, i.e., the minimum safe start-up frequency for output. or final instruction frequency ; if If the value is False, the instruction frequency generation module will force an output. Even if all other startup or operation conditions are met, the VFD will never start or will stop immediately. This embodiment introduces a grounding state. As a fundamental enabling condition and necessary prerequisite for system operation, it adds an indispensable physical security protection that conforms to industry standards to the dynamic algorithm of this invention; it ensures that while pursuing active security at the algorithm level, this invention never deviates from the basic security at the physical level, making the security of the entire system more complete and the reliability higher.

[0032] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A cloud-based liquefied petroleum gas management system, characterized in that, include: The status sensing module is used to collect tank pressure in real time; The status sensing module is also used to collect the real-time pressure of the tanker truck. The status sensing module is also used to collect the real-time flow velocity of the pipeline. The state sensing module is also used to collect static charge in the pipeline; The dynamic start-up frequency calculation module is used to calculate the dynamic pressure difference based on the tank pressure and the real-time pressure of the tank truck collected by the state sensing module; and to calculate the start-up torque demand index, which characterizes overcoming back pressure load, by combining the dynamic pressure difference with preset pump body characteristic parameters; and then to determine the minimum safe start-up frequency based on the start-up torque demand index and the preset minimum safe operating frequency. The safety attenuation factor generation module is used to dynamically calculate the safety attenuation factor based on the static charge of the pipeline collected by the state sensing module and with reference to the preset static warning threshold and the preset static trip threshold. The command frequency generation module is used to output the minimum safe start frequency determined by the dynamic start frequency calculation module as the command frequency during the start-up phase; and after the real-time flow velocity of the pipeline is detected to be stable, it switches to the stable output phase, and generates and outputs the final command frequency based on the preset economic optimization frequency and the safety attenuation factor calculated by the safety attenuation factor generation module.

2. The liquefied petroleum gas management system based on a cloud platform according to claim 1, characterized in that, The dynamic start-up frequency calculation module calculates the start-up torque demand index, specifically for: The static pressure back load is obtained by multiplying the dynamic pressure difference by a preset pressure-torque conversion coefficient. The static pressure back load is then added to a preset fixed friction torque to generate the starting torque demand index.

3. The liquefied petroleum gas management system based on a cloud platform according to claim 1, characterized in that, The dynamic startup frequency calculation module determines the minimum safe startup frequency, specifically including: The required frequency is calculated based on the starting torque demand index and the preset torque frequency calibration coefficient; The required frequency is compared with the preset minimum safe operating frequency; The larger value between the required frequency and the preset minimum safe operating frequency is taken as the minimum safe start frequency.

4. The liquefied petroleum gas management system based on a cloud platform according to claim 1, characterized in that, The command frequency generation module monitors that the real-time flow velocity in the pipeline is stable, specifically including: When the real-time flow rate of the pipeline is monitored to be stable near a preset first safety threshold and the duration exceeds a preset stabilization time threshold, the system is determined to have entered the stable output stage.

5. A cloud-based liquefied petroleum gas management system according to claim 1, characterized in that, The safety attenuation factor generation module dynamically calculates the safety attenuation factor, specifically including: When the static charge on the pipeline is lower than the electrostatic warning threshold, the safety attenuation factor is set to 1; When the static charge on the pipeline is not lower than the electrostatic warning threshold and is lower than the electrostatic trip threshold, the safety attenuation factor is calculated based on the normalized intrusion depth of the static charge on the pipeline between the electrostatic warning threshold and the electrostatic trip threshold, and in combination with a preset attenuation coefficient. When the static charge on the pipeline is not lower than the electrostatic trip threshold, the safety attenuation factor is set to 0.

6. A cloud-based liquefied petroleum gas management system according to claim 5, characterized in that, The safety attenuation factor generation module calculates the safety attenuation factor, specifically including: The normalized intrusion depth is obtained by dividing the difference between the static charge on the pipeline and the electrostatic warning threshold by the difference between the electrostatic trip threshold and the electrostatic warning threshold. The normalized penetration depth is multiplied by the preset attenuation coefficient to obtain the attenuation amount; Subtract the attenuation amount from 1 to obtain the intermediate result; The larger value between the intermediate result and 0 is used to obtain the safety attenuation factor.

7. A cloud-based liquefied petroleum gas management system according to claim 1, characterized in that, The instruction frequency generation module generates the final instruction frequency, specifically including: The final command frequency is obtained by multiplying the preset economic optimization frequency by the safety attenuation factor calculated by the safety attenuation factor generation module.

8. A cloud-based liquefied petroleum gas management system according to claim 1, characterized in that, The status sensing module is also used to collect the grounding status of the tanker truck; The command frequency generation module is also used to output the minimum safe start frequency or the final command frequency only when the tanker grounding status collected by the state perception module is validly grounded.

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