A method and system for processing an LPG filling signal

Abstract

The present application relates to the technical field of LPG filling metering and control, in particular to an LPG filling signal processing method and processing system. The method collects volume metering signals to form volume metering values and converts to obtain volume mass values, and simultaneously collects weighing metering signals to form a weighing sequence; whether to trigger a steady state acquisition operation is determined according to the volume mass value being close to a target filling amount, the weighing sequence fluctuation state or the metering difference between the volume mass value and the current weighing mass value; after triggering, the filling actuator is controlled to stop flow to form a stop flow window, sampling is performed in the window and steady state determination is performed, the weighing anchor mass value is outputted and the weighing mass value is formed when the steady state is established, a retry instruction or a weighing untrusted flag is outputted when the steady state is not established; filling control determination is generated based on the volume mass value and the weighing mass value, and a deceleration or shutdown control signal is outputted, overfilling is prevented, and an alarm or shutdown disposal instruction is outputted when abnormal conditions are met.

Description

Technical Field

[0001] This invention relates to the field of LPG filling metering and control technology, specifically to an LPG filling signal processing method and system. Background Technology

[0002] With the widespread application of LPG as a civilian and industrial fuel, the requirements for metering accuracy and filling safety in scenarios such as cylinder filling and vehicle refueling are continuously increasing. Early LPG filling primarily relied on manual weighing or mechanical scales, depending on operator experience to control valve opening and closing, resulting in limited efficiency and consistency. Subsequently, the industry gradually introduced mechanical volumetric metering devices, which convert fluid flow into mechanical rotation through rotors or flow meters, and then use gratings and photoelectric sensors to output pulse signals to accumulate volume, which is then displayed, billed, and recorded in the controller. To meet the requirements of quality delivery and regulatory metering, some equipment incorporates preset density for mass conversion based on volumetric metering. Simultaneously, pressure transmitters or load cells are used on the filling scale side in conjunction with A / D conversion and digital control to achieve mass metering and threshold control. In recent years, improvements in controller, communication, and data acquisition capabilities have made the integrated acquisition, processing, and control of multi-channel metering signals an important development direction for LPG filling equipment.

[0003] Existing LPG filling equipment still faces several challenges when using both volumetric and weighing measurement methods. First, volumetric measurement typically relies on a preset density to convert volume to mass. However, LPG density varies with temperature, composition, and pressure, leading to mass conversion errors, especially when approaching the target filling volume, where cumulative errors are likely to occur. Second, the mechanical rotor and photoelectric pulse link can be affected by mechanical wear, vibration, and interference, resulting in pulse jitter, missed readings, or abnormal jumps, causing fluctuations in volumetric measurement values. Third, the weighing channel is susceptible to changes in hose tension, tank swaying, liquid impact, and ambient vibration during filling, causing significant short-term fluctuations in the weighing signal. Directly using this for shutdown control can lead to accidental shutdowns or overcharging risks. Existing solutions often rely on a single metering channel or simple threshold filtering, making it difficult to achieve a stable balance between efficiency, accuracy, and safety. Therefore, an LPG filling signal processing method and system are needed to address these issues. Summary of the Invention

[0004] (a) Technical problem to be solved: In view of the shortcomings of the prior art, the present invention provides an LPG filling signal processing method and processing system, which solves the above-mentioned problems.

[0005] (II) Technical Solution: To achieve the above objectives, the present invention provides the following technical solution: an LPG filling signal processing method, applied to an LPG filling equipment, the LPG filling equipment including a volume measurement channel, a weighing measurement channel, and a filling actuator, the volume measurement channel being used to output a volume measurement signal, the weighing measurement channel being used to output a weighing measurement signal, and the filling actuator being used to control the filling flow rate, comprising the following steps: Step S1: Acquire the volume measurement signal, form a volume measurement value and convert it to a volumetric mass value; acquire the weighing measurement signal and form a weighing sequence; Step S2: Determine whether to trigger a steady-state acquisition operation based on the measurement state of the filling process, the measurement state including at least one of the following: the closeness of the volumetric mass value to the target filling amount; the fluctuation state of the weighing sequence; the volumetric mass value and the current weighing mass value obtained based on the weighing sequence. The measurement difference between; wherein, the current weighing mass value is the mass value calculated based on at least one sampling point of the weighing sequence; Step S3, when the steady-state acquisition operation is triggered, the filling actuator is controlled to enter the stop flow state to form a stop flow window; Step S4, the weighing sequence is sampled and a steady-state determination is performed within the stop flow window. When the steady-state determination is valid, the weighing anchor point mass value is output, and when the steady-state determination is invalid, a retry command or a weighing unreliable flag is output; Step S5, when the weighing anchor point mass value is obtained, a weighing mass value for filling control is formed based on the weighing anchor point mass value; Step S6, a filling control determination result is generated based on the volume mass value and the weighing mass value, and a control signal to the filling actuator is output accordingly to perform deceleration filling or shut-off filling to achieve overcharge prevention control, and an abnormal handling command is output when the preset abnormal conditions are met.

[0006] Furthermore, in step S2, it is determined whether to trigger a steady-state acquisition operation based on the closeness between the volume mass value and the target filling amount. Specifically, when the absolute value of the difference between the volume mass value and the target filling amount is less than or equal to a preset proximity threshold, the steady-state acquisition operation is triggered.

[0007] Furthermore, in step S2, the steady-state acquisition operation is triggered based on the measurement difference between the volume mass value and the current weighing mass value obtained based on the weighing sequence. Specifically, the steady-state acquisition operation is triggered when the absolute value of the measurement difference is greater than or equal to a preset difference threshold.

[0008] Furthermore, in step S2, the fluctuation state of the weighing sequence is obtained by calculating the fluctuation amount of the continuous sampling points of the weighing sequence within a preset time window. The fluctuation amount is the peak-to-peak value of the continuous sampling points. When the peak-to-peak value is greater than or equal to a preset fluctuation threshold, the steady-state acquisition operation is triggered.

[0009] Furthermore, in step S4, the steady-state determination is achieved by calculating the peak-to-peak value of the weighing sequence within the stop-flow window at the set of sampling points corresponding to the preset number of sampling points. When the peak-to-peak value is less than or equal to the preset steady-state threshold, the steady state is determined to be established, and the average value of the set of sampling points is converted to obtain the mass value of the weighing anchor point.

[0010] Furthermore, when the steady-state determination is not established, the retry instruction is used to control the filling actuator to re-enter the stop-flow state to re-form the stop-flow window, or to extend the duration of the stop-flow window; when the number of retries reaches the preset limit, or the duration of the stop-flow window reaches the preset duration limit, and the steady-state is still not determined, the weighing unreliable flag is output.

[0011] Furthermore, when the weighing unreliable flag is not output, the weighing mass value is used as the basis for generating the filling control judgment result. When the absolute value of the difference between the weighing mass value and the target filling amount is less than or equal to a preset deceleration threshold, it is determined to execute deceleration filling; when the weighing mass value is greater than or equal to the target filling amount, it is determined to execute shut-off filling. When the weighing unreliable flag is output, the volumetric mass value is used as the basis for generating the filling control judgment result.

[0012] Furthermore, the preset abnormal conditions include one of the following: the absolute value of the measurement difference between the volume mass value and the weighing mass value is greater than or equal to a preset abnormal threshold; the weighing unreliable flag is output; when the preset abnormal conditions are met, the abnormal handling instruction includes an alarm instruction or a filling shutdown instruction.

[0013] This invention also provides an LPG filling signal processing system applied to LPG filling equipment. The LPG filling equipment includes a volumetric metering channel, a weighing metering channel, and a filling actuator. The volumetric metering channel outputs a volumetric metering signal, the weighing metering channel outputs a weighing metering signal, and the filling actuator controls the filling flow rate. The system includes a controller, which is communicatively connected to the volumetric metering channel, the weighing metering channel, and the filling actuator. The controller is configured to execute the method according to any one of claims 1 to 8. The controller includes: a data acquisition module for acquiring the volumetric metering signal, forming a volumetric metering value, and converting it into a volumetric mass value; acquiring the weighing metering signal and forming a weighing sequence; and a metering state determination and steady-state acquisition triggering module for determining whether to trigger a steady-state acquisition operation based on the metering state of the filling process. The metering state includes at least one of the following: the closeness of the volumetric mass value to the target filling volume; the fluctuation state of the weighing sequence; and the relationship between the volumetric mass value and the target filling volume. The measurement difference between the current weighing mass values ​​obtained from the weighing sequence; wherein the current weighing mass value is a mass value calculated based on at least one sampling point of the weighing sequence; a stop-flow window control module, used to control the filling actuator to enter a stop-flow state to form a stop-flow window when the steady-state acquisition operation is triggered; a stop-flow window sampling and steady-state determination module, used to sample the weighing sequence and perform steady-state determination within the stop-flow window, outputting the weighing anchor point mass value when the steady-state determination is valid, and outputting a retry command or weighing unreliable flag when the steady-state determination is invalid; a weighing anchor point generation and weighing mass formation module, used to form a weighing mass value for filling control based on the weighing anchor point mass value when the weighing anchor point mass value is obtained; a filling control determination and execution control module, used to generate a filling control determination result based on the volume mass value and the weighing mass value, and output a control signal to the filling actuator to perform deceleration filling or shut-off filling to achieve overcharge prevention control, and output an abnormal handling command when a preset abnormal condition is met.

[0014] (III) Beneficial Effects: Compared with the prior art, the present invention provides an LPG filling signal processing method and system, which has the following beneficial effects: An LPG filling signal processing method and system, on the one hand, uses volume measurement signals to form volume measurement values ​​and converts them into volume mass values, ensuring continuous measurement and progress tracking in the filling process; on the other hand, when the volume mass value is close to the target filling amount, the weighing sequence fluctuation increases, or the measurement difference between the two channels is abnormal, a steady-state acquisition operation is triggered and the filling actuator is controlled to enter a stop-flow state to form a stop-flow window. Within the stop-flow window, the weighing sequence is sampled and steady-state determined, the weighing anchor point mass value is output, and a weighing mass value for control is formed, thereby obtaining a reliable weighing benchmark under low disturbance conditions at the end of the filling stage. In this way, the system can use the weighing mass value as the key control basis when approaching the target filling volume and output deceleration or shutdown control signals. This reduces the impact of the cumulative deviation caused by the volume measurement relying on the preset density conversion on the end shutdown, and reduces the misjudgment and accidental shutdown of the weighing signal caused by vibration, swaying and liquid impact during continuous filling. At the same time, when the steady-state judgment fails, it outputs a retry command or weighing unreliable flag and enters the corresponding control strategy, improving the robustness to working conditions such as pulse abnormality, density conversion deviation and weighing instability. This effectively suppresses the risk of overfilling while taking into account filling efficiency and metering consistency. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the framework of an LPG filling signal processing method provided by the present invention.

[0016] Figure 2 This is a flowchart illustrating an LPG filling signal processing method provided by the present invention.

[0017] Figure 3 This is a schematic diagram of the structure of an LPG filling signal processing system provided by the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0020] Please see Figure 1-2 , Figure 1A schematic diagram of the framework of an LPG filling signal processing method provided by the present invention; Figure 2 This invention provides a flowchart of an LPG filling signal processing method. The method, applied to an LPG filling equipment, includes a volumetric metering channel, a weighing metering channel, and a filling actuator. The volumetric metering channel outputs a volumetric metering signal, the weighing metering channel outputs a weighing metering signal, and the filling actuator controls the filling flow rate. The method comprises the following steps: Step S1: Acquire the volumetric metering signal, generate a volumetric metering value, and convert it to a volumetric mass value; acquire the weighing metering signal and generate a weighing sequence; Step S2: Determine whether to trigger a steady-state acquisition operation based on the metering state of the filling process. The metering state includes at least one of the following: the closeness of the volumetric mass value to the target filling volume; the fluctuation state of the weighing sequence; the difference between the volumetric mass value and the current weighing mass value obtained based on the weighing sequence. The measurement difference between; wherein, the current weighing mass value is the mass value calculated based on at least one sampling point of the weighing sequence; Step S3, when the steady-state acquisition operation is triggered, the filling actuator is controlled to enter the stop flow state to form a stop flow window; Step S4, the weighing sequence is sampled and a steady-state determination is performed within the stop flow window. When the steady-state determination is valid, the weighing anchor point mass value is output, and when the steady-state determination is invalid, a retry command or a weighing unreliable flag is output; Step S5, when the weighing anchor point mass value is obtained, a weighing mass value for filling control is formed based on the weighing anchor point mass value; Step S6, a filling control determination result is generated based on the volume mass value and the weighing mass value, and a control signal to the filling actuator is output accordingly to perform deceleration filling or shut-off filling to achieve overcharge prevention control, and an abnormal handling command is output when the preset abnormal conditions are met.

[0021] In this embodiment, the volume measurement channel of the LPG filling equipment is a measurement structure consisting of a mechanical rotor, a grating, and a photoelectric sensor. The output volume measurement signal is a pulse signal or a pulse count value. In step S1, the controller counts and accumulates the volume measurement signal to obtain the volume measurement value. The volume measurement value is the cumulative number of pulses or the pulse increment per unit time. The pulse quantity is converted into volume quantity through a pre-stored volume coefficient, which is used to characterize the volume increment corresponding to a single pulse, thereby obtaining the cumulative volume or volume increment. Subsequently, the controller converts the volume quantity into a volumetric mass value based on the density parameter. The density parameter is a preset density calibrated at the factory and configured in the equipment parameters according to batch, temperature, or gas source composition. The conversion relationship satisfies that the volumetric mass value is equal to the product of the volume quantity and the density parameter. Thus, the volumetric mass value is used to reflect the filling quality progress.

[0022] The weighing and metering channel includes a weighing sensor or pressure transmitter, a signal conditioning circuit and an A / D conversion unit. The controller periodically samples the weighing and metering signal to form a weighing sequence. Each sampling point in the weighing sequence is converted into a mass reading by a calibration coefficient, which serves as the source of the current weighing mass value mentioned in step S2. The current weighing mass value is taken as the converted value of the most recent sampling point in the weighing sequence, or as the conversion result of the statistical values ​​of several sampling points within a preset sampling window to suppress occasional jumps.

[0023] In step S2, the controller determines whether to trigger a steady-state acquisition operation based on the metering status. The metering status includes at least one of the following: when the difference between the volumetric mass value and the target filling amount enters the end range, it indicates that the filling is close to the target and the reliability of the shutdown judgment needs to be improved; when the weighing sequence fluctuates significantly during continuous filling due to changes in hose tension, tank swaying, or liquid impact, it indicates that the weighing signal is unstable under flowing conditions; when the metering difference between the volumetric mass value and the current weighing mass value exceeds the allowable range, it indicates that there is a consistency deviation between the two channels and a reliable weighing benchmark needs to be obtained for verification.

[0024] After triggering the steady-state acquisition operation, in step S3, the controller outputs a flow-stop control signal to the filling actuator, causing the valve to close or the pump to stop, thereby reducing the filling flow rate to zero or near zero, thus forming a flow-stop window. The function of this flow-stop window is to switch the weighing channel from a "flow disturbance environment" to a "low disturbance environment", reducing the impact of dynamic liquid impact and mechanical vibration coupling on the weighing reading.

[0025] In step S4, the controller continues to acquire the window subsequence of the weighing sequence at the same or increased sampling frequency within the stop window, and performs steady-state determination on the subsequence. The steady-state determination can be achieved by using the fluctuation threshold method, that is, calculating the difference between the maximum and minimum values ​​of several consecutive sampling points within the stop window as the fluctuation. When the fluctuation is not greater than the steady-state threshold, the weighing is considered to have entered a steady state and the weighing anchor point mass value is output. The weighing anchor point mass value is the average value of the window subsequence converted to reduce the influence of quantization noise on the single-point reading.

[0026] If the steady-state determination is not established, the controller outputs a retry command to re-establish the stop-flow window or extend the stop-flow window. If a steady state cannot be established after reaching the preset number of retry attempts or the upper limit of the stop-flow duration, a weighing unreliable flag is output to indicate that the weighing channel is insufficient to support the end-point control reference under the current operating conditions.

[0027] In step S5, when the mass value of the weighing anchor point is obtained, the controller uses it as the weighing mass value for filling control, so that the end control decision is based on the reliable weighing result under low disturbance conditions.

[0028] In step S6, the controller generates a filling control judgment result based on the volumetric mass value and the weighed mass value and outputs a control signal. Specifically, this may include determining whether to slow down or shut down filling based on the difference between the weighed mass value and the target filling amount when approaching the target, thereby reducing the flow rate in advance and quickly shutting down when reaching the target to suppress inertial overshoot. If a weighing unreliable flag is output, the controller can degenerate to use the volumetric mass value as the main basis for slowing down or shutting down to ensure continuous controllability. At the same time, when the measurement difference between the volumetric mass value and the weighed mass value exceeds the abnormal threshold or the weighing unreliable flag is output, etc., which meet the preset abnormal conditions, the controller outputs an abnormal handling command to trigger safety actions such as alarm or forced shutdown. This achieves the suppression of the risk of misjudgment caused by density conversion deviation, abnormal volume measurement, and weighing fluctuation, enabling those skilled in the art to complete the system implementation and obtain the overcharge prevention effect based on the above signal acquisition, conversion relationship, trigger logic, flow stop control, steady state judgment, and control output.

[0029] Furthermore, in step S2, it is determined whether to trigger a steady-state acquisition operation based on the closeness between the volume mass value and the target filling amount. Specifically, when the absolute value of the difference between the volume mass value and the target filling amount is less than or equal to a preset proximity threshold, the steady-state acquisition operation is triggered.

[0030] In this embodiment, after completing step S1, the controller can obtain the volumetric mass value and the target filling volume in real time. The volumetric mass value is used to characterize the current cumulative filling volume calculated based on the volumetric metering channel, and the target filling volume is the target mass preset for this filling task. To improve the reliability of the end-point shutdown and reduce the risk of overcharging, step S2 uses "proximity" as the triggering basis for the steady-state acquisition operation. Specifically, the controller calculates the difference between the volumetric mass value and the target filling volume, and takes its absolute value as the distance to the target. When the absolute value is less than or equal to a preset proximity threshold, it is determined that the filling has entered the end-point interval and the steady-state acquisition operation is triggered. The preset proximity threshold is configured in the device parameters, and its setting principle is to ensure that the triggering time is within the range that can be reduced. Within the safe range of "suppressing inertial overshoot by slowing down or stopping flow," that is, when the volumetric mass value is close to the target filling volume, a flow-stopping window is introduced in advance to obtain the weighing anchor point mass value under low disturbance conditions and form a weighing mass value for control. This makes the subsequent deceleration filling or shut-off filling decisions more reliable. Through this triggering method, the system can limit the steady-state acquisition operation to be performed in the critical stage at the end. This avoids frequent flow-stopping in the early stage of filling, which affects efficiency, and ensures that the control logic based on the weighing anchor point is switched in time when approaching the target. This reduces the probability of overfilling caused by the superposition of volume conversion error, flow inertia, and dynamic fluctuations in weighing. This allows those skilled in the art to trigger the judgment and complete the corresponding control by calculating the difference and comparing it with the threshold.

[0031] Furthermore, in step S2, the steady-state acquisition operation is triggered based on the measurement difference between the volume mass value and the current weighing mass value obtained based on the weighing sequence. Specifically, the steady-state acquisition operation is triggered when the absolute value of the measurement difference is greater than or equal to a preset difference threshold.

[0032] In this embodiment, the controller obtains the volumetric mass value and the weighing sequence in step S1, respectively. The volumetric mass value is used to characterize the cumulative filling mass converted from the volumetric metering channel, and the weighing sequence is used to characterize the real-time sampling result of the weighing metering channel during the filling process. To monitor the consistency of the two channels' measurements online and obtain a reliable weighing benchmark in a timely manner when deviations occur, the measurement difference is used as the trigger for steady-state acquisition in step S2. Specifically, the controller obtains the current weighing mass value based on the weighing sequence. The current weighing mass value can be obtained by calibration and conversion from at least one sampling point of the weighing sequence, for example, by taking the latest sampling point and multiplying it by a calibration coefficient or obtaining a mass reading through an equivalent conversion relationship, thereby forming a mass value comparable to the volumetric mass value in the same dimension. Subsequently, the controller calculates the measurement difference and takes its absolute value. When the absolute value is greater than or equal to a preset difference threshold, it determines that there is an abnormal deviation in the measurement of the two channels and triggers the operation. The system initiates a steady-state acquisition operation, causing the filling actuator to enter a flow-stop state, forming a flow-stop window. This allows for steady-state determination of the weighing sequence under low-disturbance conditions, and outputs the weighing anchor point mass value. The triggering mechanism ensures that when the volumetric mass value may deviate due to density conversion errors, pulse anomalies, or mechanical wear, or when the weighing side experiences vibration and impact during continuous filling, causing instantaneous distortion of the current weighing mass value, the system does not directly use the instantaneous difference as the shutdown conclusion. Instead, it triggers the flow-stop window to obtain a more reliable weighing anchor point for verification, thus avoiding misjudging short-term disturbances or cumulative conversion errors as actual changes in filling volume. Simultaneously, the preset difference threshold can be configured according to equipment range, measurement accuracy, and safety redundancy requirements. This allows those skilled in the art to achieve consistency monitoring triggering by "generating the current weighing mass value, calculating the measurement difference, and comparing it with the threshold," and then entering the steady-state acquisition process after triggering to complete overcharge prevention control.

[0033] Furthermore, the fluctuation state of the weighing sequence is obtained by calculating the fluctuation amount of the continuous sampling points of the weighing sequence within a preset time window. The fluctuation amount is the peak-to-peak value of the continuous sampling points. When the peak-to-peak value is greater than or equal to a preset fluctuation threshold, the steady-state acquisition operation is triggered.

[0034] In this embodiment, to enable the controller to quantify the dynamic disturbance of the weighing and metering channel during continuous filling in a feasible and determinable manner, step S2 defines the "fluctuation state of the weighing sequence" as the fluctuation calculation result based on the continuous sampling points within a preset time window. Specifically, the controller samples the weighing and metering signal at a fixed sampling period to form a weighing sequence, and maintains a sliding time window of length N during operation. The window contains the set of the nearest continuous sampling points, and then calculates the fluctuation of this set of sampling points. The fluctuation is represented by the peak-to-peak value, that is, the difference between the maximum and minimum sampling values ​​within the window, to reflect the up-and-down swing of the weighing reading within the time window. When the peak-to-peak value is greater than or equal to the preset fluctuation threshold, the controller determines that the weighing sequence is in a strong fluctuation state, which usually corresponds to changes in hose tension. Significant fluctuations in weighing readings caused by tank swaying, liquid impact, or on-site vibration can easily lead to misjudgments if the weighing readings are directly used for end-point shutdown under flowing conditions. Therefore, a steady-state acquisition operation is triggered, controlling the filling actuator to enter a flow-stop state to form a flow-stop window. Within the flow-stop window, a steady-state determination is performed on the weighing sequence to obtain the weighing anchor point mass value. By introducing peak-to-peak value, a simple and engineering-reproducible fluctuation index, the system can quickly identify periods when the weighing signal is unavailable without relying on complex algorithms and actively switch to a low-disturbance sampling mode of "flow-stop acquisition anchor point". This improves the reliability of the weighing benchmark and reduces the risk of overcharging or erroneous shutdown. Those skilled in the art can use this to complete the fluctuation state determination and triggering logic by setting a time window, calculating the peak-to-peak value, and comparing it with the fluctuation threshold.

[0035] Furthermore, in step S4, the steady-state determination is achieved by calculating the peak-to-peak value of the weighing sequence within the stop-flow window at the set of sampling points corresponding to the preset number of sampling points. When the peak-to-peak value is less than or equal to the preset steady-state threshold, the steady state is determined to be established, and the average value of the set of sampling points is converted to obtain the mass value of the weighing anchor point.

[0036] In this embodiment, to determine whether the weighing signal has entered a stable state that can be used as a control reference in a quantifiable and reproducible manner within the stop-flow window, step S4 adopts a steady-state determination mechanism based on peak-to-peak value to generate the mass value of the weighing anchor point: After step S3 triggers the steady-state acquisition operation, the controller controls the filling actuator to stop the flow to form a stop-flow window. Within the stop-flow window, the weighing sequence continues to be acquired at a fixed sampling period, and a set of continuous sampling points corresponding to a preset number of sampling points is selected from the stop-flow window as the steady-state determination object; the controller calculates the peak-to-peak value of this set of sampling points to characterize the residual swing of the weighing reading after the flow stops. If the peak-to-peak value is less than or equal to a preset steady-state threshold, it is considered that the dynamic disturbances such as tank sway, hose tension rebound, and liquid impact have been sufficiently attenuated, and the weighing reading has entered a steady state, thereby determining that a steady state has been formed. The system establishes and outputs the weighing anchor point mass value. The weighing anchor point mass value is generated by converting the average value of the sampling point set. The conversion is based on the calibration relationship of the weighing channel to map digital quantities or electrical signals to the mass dimension, so that the anchor point result has both anti-quantization noise capability and anti-single-point anomaly capability, avoiding the influence of random fluctuations in a single sampling on control decisions. Through this steady-state determination and anchor point generation method, the system can form a reliable weighing benchmark under low disturbance conditions of current stoppage and provide it for subsequent steps S5 to S6 for deceleration or shutdown determination, thereby improving the reliability of end shutdown and reducing the risk of overcharging. Those skilled in the art can achieve steady-state determination and output of weighing anchor point mass value by selecting a sampling point set, calculating the peak-to-peak value and comparing it with the steady-state threshold, and calibrating and converting the set mean.

[0037] Furthermore, when the steady-state determination is not established, the retry instruction is used to control the filling actuator to re-enter the stop-flow state to re-form the stop-flow window, or to extend the duration of the stop-flow window; when the number of retries reaches the preset limit, or the duration of the stop-flow window reaches the preset duration limit, and the steady-state is still not determined, the weighing unreliable flag is output.

[0038] In this embodiment, to ensure a reliable weighing anchor point usable for control under different field disturbance intensities, different hose rebound characteristics, and different tank sway decay rates, while avoiding endless flow interruptions affecting filling efficiency, step S4 introduces a retry and degradation mechanism when the steady-state determination is not established: when the peak-to-peak value calculated by the controller for the preset sampling point set within the flow interruption window is still greater than the preset steady-state threshold, it indicates that the weighing reading has not yet stabilized. The controller outputs a retry command. The execution method of the retry command includes controlling the filling actuator to re-enter the flow interruption state to re-establish a new flow interruption window, allowing the weighing system to obtain a new low-disturbance sampling period, or extending the duration of the flow interruption window based on the current flow interruption window, so as to allow more time for tank sway decay and pipeline stress release, thereby increasing the probability of a successful steady-state determination; at the same time, the controller sets the number of retry attempts and the duration of the flow interruption window. The system employs upper limit constraints and count and time management. When the number of retries reaches the preset upper limit, or the duration of the current stop window reaches the preset upper limit, and a steady state is still not determined, the controller outputs a weighing unreliable flag. This clearly indicates that the weighing channel cannot provide a reliable benchmark that meets the steady-state requirements under the current operating conditions. Consequently, subsequent step S6 can switch to a control strategy based primarily on volumetric mass values ​​and, in conjunction with abnormal handling logic, implement safe shutdown or alarm. Through this mechanism, the system prioritizes retries to improve the success rate of anchor point acquisition when a steady-state anchor point can be obtained. When a steady-state anchor point cannot be obtained, the system promptly degrades and provides a clear status indicator, avoiding the participation of erroneous anchor points caused by continuous vibration in the control process. It also prevents efficiency degradation due to excessively long current stoppages. Those skilled in the art can use this to implement retry command output, retry counting and current stop timing, upper limit determination, and the output and transmission of the weighing unreliable flag.

[0039] Furthermore, when the weighing unreliable flag is not output, the weighing mass value is used as the basis for generating the filling control judgment result. When the absolute value of the difference between the weighing mass value and the target filling amount is less than or equal to a preset deceleration threshold, it is determined to execute deceleration filling; when the weighing mass value is greater than or equal to the target filling amount, it is determined to execute shut-off filling. When the weighing unreliable flag is output, the volumetric mass value is used as the basis for generating the filling control judgment result.

[0040] In this embodiment, to balance shutdown accuracy and system availability at the end stage, step S6 adopts a control judgment strategy of "weighing priority and degraded backoff": when step S4 does not output a weighing unreliable flag and step S5 has generated a weighing mass value for filling control, the controller uses the weighing mass value as the main basis for generating the filling control judgment result. This is because the weighing mass value originates from the weighing anchor point mass value within the stop flow window, and its acquisition time is under low disturbance conditions, which can effectively suppress the weighing reading drift caused by vibration, hose tension changes, and liquid impact during continuous filling, thus making it more suitable as the end control reference. Specifically, the controller calculates the difference between the weighing mass value and the target filling volume and takes the absolute value. When the absolute value is less than or equal to a preset deceleration threshold, it determines that the filling has entered the end fine control stage and outputs a deceleration filling control signal to reduce the flow rate of the filling actuator to reduce inertial overshoot. When the weighing mass value is greater than or equal to a preset deceleration threshold, the controller determines that the filling has entered the end fine control stage and outputs a deceleration filling control signal to reduce the flow rate of the filling actuator to reduce inertial overshoot. When the filling volume equals the target filling volume, the system determines that the target has been reached or exceeded and outputs a shut-off filling control signal to achieve rapid shut-off and suppress overfilling. On the other hand, when step S4 outputs a weighing unreliable flag, it indicates that a reliable weighing benchmark that meets the steady-state requirements cannot be obtained under the current operating conditions. If the weighing mass value is used for control, it is easy to introduce misjudgment. Therefore, the controller automatically switches to using the volume mass value as the basis for generating the filling control judgment result. It uses the continuous and stable metering characteristics of the volume metering channel to maintain the controllability of filling and combines the abnormal handling logic to execute alarms or shut-off when necessary to ensure safety. Through the above strategies, the system can improve the accuracy of the end shut-off and reduce the risk of overfilling when the weighing is reliable, and keep the control link uninterrupted and avoid erroneous weighing from participating in the decision when the weighing is unreliable. This enables those skilled in the art to implement control basis selection based on status flags, deceleration threshold determination and shut-off determination, and corresponding actuator control output.

[0041] Furthermore, the preset abnormal conditions include one of the following: the absolute value of the measurement difference between the volume mass value and the weighing mass value is greater than or equal to a preset abnormal threshold; the weighing unreliable flag is output; when the preset abnormal conditions are met, the abnormal handling instruction includes an alarm instruction or a filling shutdown instruction.

[0042] In this embodiment, to promptly initiate safety procedures under risky conditions such as increased measurement deviation or unavailability of the weighing channel, step S6 sets preset abnormal conditions and outputs an abnormal handling command when these conditions are met: After obtaining the volumetric mass value and the weighed mass value, the controller calculates the measurement difference between the two and takes its absolute value. When the absolute value is greater than or equal to the preset abnormal threshold, it indicates a significant inconsistency between the volumetric measurement conversion result and the weighing result based on the stop-flow anchor point. This may correspond to situations such as accumulated density conversion deviation, abnormal volumetric measurement pulse, mechanical wear, or weighing link drift. Continuing with conventional control could easily lead to deviations in filling volume from the target or even overfilling. Therefore, this state is judged as abnormal and abnormal handling is triggered. Furthermore, when step S4 outputs a weighing unreliable flag, it indicates that the weighing signal cannot meet the steady-state requirements under the current operating conditions. Although the system can continue to control based on the volumetric mass value according to the degradation strategy, This state also indicates a reduced safety margin or increased environmental disturbance, and is therefore included as one of the preset abnormal conditions to provide alerts and handle risky operating conditions. When any of the above preset abnormal conditions are met, the controller outputs an abnormal handling instruction. The abnormal handling instruction includes at least an alarm instruction to prompt the operator to pay attention to the equipment status and conduct an inspection, or a filling shutdown instruction to directly control the filling actuator to stop filling and thus eliminate the risk of overfilling. The specific use of alarm or shutdown can be configured according to the equipment's safety strategy, abnormal level, or on-site management requirements. Through the setting of this abnormal condition and handling instruction, the system can proactively enter a safety mode when the two channels of metering are significantly different or the weighing is unavailable, avoiding safety accidents caused by continuing filling under conditions of inconsistent metering or unreliable signals. It also provides a clear engineering implementation path for those skilled in the art to implement abnormal threshold comparison, status flag triggering, and alarm or shutdown output.

[0043] This invention also provides an LPG filling signal processing system applied to LPG filling equipment. The LPG filling equipment includes a volumetric metering channel, a weighing metering channel, and a filling actuator. The volumetric metering channel outputs a volumetric metering signal, the weighing metering channel outputs a weighing metering signal, and the filling actuator controls the filling flow rate. The system includes a controller, which is communicatively connected to the volumetric metering channel, the weighing metering channel, and the filling actuator. The controller is configured to execute the method according to any one of claims 1 to 8. The controller includes: a data acquisition module for acquiring the volumetric metering signal, forming a volumetric metering value, and converting it into a volumetric mass value; acquiring the weighing metering signal and forming a weighing sequence; and a metering state determination and steady-state acquisition triggering module for determining whether to trigger a steady-state acquisition operation based on the metering state of the filling process. The metering state includes at least one of the following: the closeness of the volumetric mass value to the target filling volume; the fluctuation state of the weighing sequence; and the relationship between the volumetric mass value and the target filling volume. The measurement difference between the current weighing mass values ​​obtained from the weighing sequence; wherein the current weighing mass value is a mass value calculated based on at least one sampling point of the weighing sequence; a stop-flow window control module, used to control the filling actuator to enter a stop-flow state to form a stop-flow window when the steady-state acquisition operation is triggered; a stop-flow window sampling and steady-state determination module, used to sample the weighing sequence and perform steady-state determination within the stop-flow window, outputting the weighing anchor point mass value when the steady-state determination is valid, and outputting a retry command or weighing unreliable flag when the steady-state determination is invalid; a weighing anchor point generation and weighing mass formation module, used to form a weighing mass value for filling control based on the weighing anchor point mass value when the weighing anchor point mass value is obtained; a filling control determination and execution control module, used to generate a filling control determination result based on the volume mass value and the weighing mass value, and output a control signal to the filling actuator to perform deceleration filling or shut-off filling to achieve overcharge prevention control, and output an abnormal handling command when a preset abnormal condition is met.

[0044] Working Principle: The core idea of ​​this invention is to combine the advantages of two measurement methods. Volumetric measurement is responsible for "continuous progress tracking," while weighing is responsible for "providing a more reliable quality benchmark at the end." During stages where weighing is easily interfered with, one or more short pauses in the flow create a quieter measurement environment to obtain reliable weighing results. The volumetric measurement channel outputs a volumetric measurement signal, which comes from pulses generated by the mechanical rotor driving the grating. The controller counts and accumulates the pulses to obtain the volumetric measurement value, and then uses a preset conversion relationship to convert the volumetric measurement value into a volumetric mass value. This volumetric mass value acts like a continuously updating progress bar, telling the system how much has been filled. The weighing measurement channel outputs a weighing measurement signal. The controller samples this signal at fixed intervals to form a weighing sequence. The weighing sequence reflects the weight change on the weighing platform at that moment. However, during the filling process, it is often affected by changes in hose tension, can swaying, liquid impact, and ground vibration, causing it to fluctuate.

[0045] The system doesn't frequently stop weighing at the beginning. Instead, it first determines whether to enter steady-state acquisition based on the "measuring status." The measuring status can fall into one of three categories: First, the volumetric mass value is close to the target filling volume, indicating the endpoint is approaching. At this point, even small errors could lead to overfilling, so the reliability of the end-point determination needs to be improved. Second, the weighing sequence fluctuates greatly, indicating that the weighing is unstable under flowing conditions. Directly using the weighing reading to determine if the quantity has been reached can easily lead to misjudgment. Third, the volumetric mass value differs significantly from the current weighing mass value, indicating inconsistency between the two measurement results. This could be due to accumulated density conversion errors, pulse anomalies, weighing disturbances, or link drift, requiring further confirmation of the actual filling quality. Once any of these conditions occur, the system triggers steady-state acquisition and proceeds to the next step.

[0046] The key action in steady-state acquisition is "stopping and then weighing," which means controlling the filling actuator to enter a flow-stopped state, creating a flow-stop window. The purpose of this flow-stop window is to switch the weighing process from a "dynamic disturbance environment" to a "low disturbance environment." Once the flow stops, the liquid impact significantly decreases, the tension changes in the hose tend to stabilize, and the tank sway gradually diminishes, making it easier for the weighing reading to stabilize. Within the flow-stop window, the controller continues to sample the weighing sequence and performs a steady-state determination. In simple terms, steady-state determination involves checking whether the weighing reading fluctuates within this short period. If the fluctuation is very small, it is considered to have entered a steady state; if it is still fluctuating significantly, it is considered not yet stable.

[0047] When the steady-state determination is successful, the system outputs a "weighing anchor point mass value," which can be understood as a reliable weighing point obtained in a quiet environment. This value is then used as the weighing mass value for filling control. The significance of this is that the end-point control no longer relies on the easily fluctuating instantaneous weighing reading during continuous filling, but instead on a more reliable reference value confirmed by a flow stop. Conversely, if the steady-state determination is unsuccessful, the system will not force an unstable weighing result into a decision. Instead, it provides two handling options: one is to output a retry command, causing the equipment to stop again or extending the flow stop time to attempt to obtain a steady-state anchor point; the other is to output a weighing unreliable flag if the retry still fails, explicitly telling subsequent control components that "the weighing channel is unreliable at this moment."

[0048] Upon entering the control phase, the system adopts a "weighing priority, downgrade if necessary" approach to generate filling control judgment results and output control signals. If no weighing unreliable flag is output, it indicates that the weighing anchor point has been obtained and is reliable. In this case, the system primarily uses the weighing mass value to determine whether deceleration and shutdown are necessary: ​​when the target is approaching, deceleration is initiated to reduce the flow rate and minimize inertial overshoot; when the weighing mass value reaches or exceeds the target filling volume, shutdown is initiated to quickly stop filling and prevent overfilling. If a weighing unreliable flag is output, the system no longer relies on weighing for critical decisions but reverts to using the volumetric mass value as the primary basis for control, ensuring the process remains controllable while enhancing safety margins through anomaly handling logic.

[0049] To prevent risks associated with continued filling due to inconsistent measurement or unreliable signals, the system is equipped with preset abnormal conditions and outputs abnormal handling commands. Abnormal conditions can include a significant difference between the volumetric mass value and the weighed mass value, indicating a clear divergence between the two metering links, posing a risk of overcharging or undercharging if conventional control is continued; or the output of a weighing unreliability flag, indicating that the weighing channel is unavailable or unstable, requiring alerts or safety actions. Once an abnormal condition is met, the system will output an alarm command to alert the operator, or it can output a filling shutdown command to directly stop filling, ensuring safety.

[0050] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0051] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An LPG filling signal processing method, applied to an LPG filling equipment, the LPG filling equipment comprising a volumetric metering channel, a weighing metering channel, and a filling actuator, wherein the volumetric metering channel is used to output a volumetric metering signal, the weighing metering channel is used to output a weighing metering signal, and the filling actuator is used to control the filling flow rate, characterized in that... The process includes the following steps: Step S1: Acquire the volume measurement signal, form a volume measurement value, and convert it into a volumetric mass value; acquire the weighing measurement signal and form a weighing sequence; Step S2: Determine whether to trigger a steady-state acquisition operation based on the measurement status of the filling process, wherein the measurement status includes at least one of the following: the degree of closeness between the volumetric mass value and the target filling amount; the fluctuation state of the weighing sequence; the measurement difference between the volumetric mass value and the current weighing mass value obtained based on the weighing sequence; wherein the current weighing mass value is a mass value converted based on at least one sampling point of the weighing sequence; Step S3: When the steady-state acquisition operation is triggered, control the filling process. Step S4: The actuator enters a stop-flow state to form a stop-flow window; Step S5: The weighing sequence is sampled and a steady-state determination is performed within the stop-flow window. When the steady-state determination is successful, the weighing anchor point mass value is output; when the steady-state determination is unsuccessful, a retry command or a weighing unreliable flag is output; Step S6: When the weighing anchor point mass value is obtained, a weighing mass value for filling control is formed based on the weighing anchor point mass value; Step S7: A filling control determination result is generated based on the volume mass value and the weighing mass value, and a control signal is output to the filling actuator to perform deceleration filling or shut-off filling to achieve overcharge prevention control, and an abnormal handling command is output when preset abnormal conditions are met.

2. The LPG filling signal processing method according to claim 1, characterized in that, In step S2, a steady-state acquisition operation is triggered based on the proximity of the volume mass value to the target filling amount. Specifically, the steady-state acquisition operation is triggered when the absolute value of the difference between the volume mass value and the target filling amount is less than or equal to a preset proximity threshold.

3. The LPG filling signal processing method according to claim 1, characterized in that, In step S2, the steady-state acquisition operation is triggered based on the measurement difference between the volume mass value and the current weighing mass value obtained based on the weighing sequence. Specifically, the steady-state acquisition operation is triggered when the absolute value of the measurement difference is greater than or equal to a preset difference threshold.

4. The LPG filling signal processing method according to claim 1, characterized in that: In step S2, the fluctuation state of the weighing sequence is obtained by calculating the fluctuation amount of the continuous sampling points of the weighing sequence within a preset time window. The fluctuation amount is the peak-to-peak value of the continuous sampling points. When the peak-to-peak value is greater than or equal to a preset fluctuation threshold, the steady-state acquisition operation is triggered.

5. The LPG filling signal processing method according to claim 1, characterized in that: In step S4, the steady state determination is achieved by calculating the peak-to-peak value of the weighing sequence within the stop-flow window at the set of sampling points corresponding to the preset number of sampling points. When the peak-to-peak value is less than or equal to the preset steady state threshold, the steady state is determined to be established, and the average value of the set of sampling points is converted to obtain the mass value of the weighing anchor point.

6. The LPG filling signal processing method according to claim 1, characterized in that: When the steady-state determination is not met, the retry instruction is used to control the filling actuator to re-enter the stop-flow state to re-form the stop-flow window, or to extend the duration of the stop-flow window; When the number of retries reaches the preset limit, or the duration of the interruption window reaches the preset duration limit, and a steady state is still not determined, the weighing unreliable flag is output.

7. The LPG filling signal processing method according to claim 1, characterized in that: In the absence of the weighing unreliable flag, the weighing mass value is used as the basis for generating the filling control judgment result. When the absolute value of the difference between the weighing mass value and the target filling amount is less than or equal to the preset deceleration threshold, it is determined to execute deceleration filling. When the weighing mass value is greater than or equal to the target filling amount, it is determined to execute shut-off filling. When the weighing unreliable flag is output, the volumetric mass value is used as the basis for generating the filling control judgment result.

8. The LPG filling signal processing method according to claim 1, characterized in that: The preset abnormal conditions include one of the following: the absolute value of the measurement difference between the volume mass value and the weighing mass value is greater than or equal to the preset abnormal threshold; the weighing unreliable flag is output; when the preset abnormal conditions are met, the abnormal handling instruction includes an alarm instruction or a filling shutdown instruction.

9. An LPG filling signal processing system, applied to an LPG filling equipment, the LPG filling equipment comprising a volumetric metering channel, a weighing metering channel, and a filling actuator, wherein the volumetric metering channel is used to output a volumetric metering signal, the weighing metering channel is used to output a weighing metering signal, and the filling actuator is used to control the filling flow rate, characterized in that... The system includes a controller, which is communicatively connected to the volume measurement channel, the weighing measurement channel, and the filling actuator. The controller is configured to execute the method according to any one of claims 1 to 8. The controller includes: a data acquisition module for acquiring the volume measurement signal, forming a volume measurement value, and converting it into a volumetric mass value; acquiring the weighing measurement signal and forming a weighing sequence; and a measurement state determination and steady-state acquisition trigger module for determining whether to trigger a steady-state acquisition operation based on the measurement state of the filling process. The measurement state includes at least one of the following: the degree of closeness between the volumetric mass value and the target filling amount; the fluctuation state of the weighing sequence; and the measurement difference between the volumetric mass value and the current weighing mass value obtained based on the weighing sequence. The current weighing mass value is a mass value calculated based on at least one sampling point of the weighing sequence. The system includes: a stop-flow window control module, used to control the filling actuator to enter a stop-flow state to form a stop-flow window when the steady-state acquisition operation is triggered; a stop-flow window sampling and steady-state determination module, used to sample the weighing sequence and perform steady-state determination within the stop-flow window, outputting the weighing anchor mass value when the steady-state determination is valid, and outputting a retry command or a weighing unreliable flag when the steady-state determination is invalid; a weighing anchor generation and weighing mass formation module, used to form a weighing mass value for filling control based on the weighing anchor mass value when the weighing anchor mass value is obtained; and a filling control determination and execution control module, used to generate a filling control determination result based on the volume mass value and the weighing mass value, and output a control signal to the filling actuator to perform deceleration filling or shut-off filling to achieve overcharge prevention control, and output an abnormal handling command when preset abnormal conditions are met.

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