Oiling pump idling protection method and system, terminal equipment and storage medium

Abstract

The invention discloses a gasoline pump idling protection method and system and terminal equipment. The method comprises the following steps: detecting the working current of the petrol pump in real time, and comparing the working current with a threshold value set between an idle current and a normal load current; and when the working current is continuously lower than the threshold value for a preset delay time, generating a protection signal and cutting off a power supply loop of the refueling pump. The system comprises a petrol pump, a starting circuit and an idling detection circuit. The starting circuit is composed of a refueling switch SA, a coil of a contactor KM and a delay disconnection contact of a time relay KT and used for controlling starting and stopping of the pump. The idling detection circuit is composed of a current relay KA and a time relay KT coil which are connected in series with the main loop; and when the pump idles and the current is too low, the KA contact acts to enable the KT coil to be electrified and delayed, and finally, the KM coil circuit is cut off by the delay disconnection contact of the KT, so that protection is realized. The method can effectively identify and avoid idling of the petrol pump, prevents equipment from being damaged, and prolongs the service life.

Description

Technical Field

[0001] This application relates to the field of pump equipment protection technology, and in particular to a method, system, terminal equipment, storage medium and control method for protecting a refueling pump from idling. Background Technology

[0002] Fuel pumps are core components of various refueling equipment, widely used in automotive, marine, and aviation refueling. In actual operation, fuel pumps may run dry for extended periods without fuel, due to low fuel tank levels, blocked inlet lines, valves not opening, or other malfunctions. Prolonged dry running of a fuel pump can cause numerous problems. For example, the pump impeller and seals, operating at high speed without lubrication and cooling, generate intense friction and high temperatures, leading to rapid wear, aging, and even burnout, severely shortening the pump's lifespan. Furthermore, the lack of fuel inside the pump during dry running can cause cavitation, generating abnormal noise and vibration, affecting equipment stability and the operating environment. Finally, while running dry, the fuel pump still consumes electrical energy without delivering fuel, resulting in unnecessary energy waste.

[0003] In existing technologies, dry running protection for pumps typically employs methods such as level switches and flow sensors. However, level switches only provide protection when the tank level reaches a fixed low level, failing to reflect the actual oil supply at the pump inlet in real time. While flow sensors can detect flow rate, their installation cost is high, and they may misjudge under viscous media or low-flow conditions. Furthermore, some simple current detection methods may fail to distinguish between brief dry running during startup or short-term low flow caused by residual media within the pump, easily leading to frequent malfunctions and impacting refueling efficiency and user experience.

[0004] Furthermore, in existing technologies, a mechanical flow switch is used to detect the flow rate in the pipeline. When no flow is detected (the fuel pump is running dry), the power to the fuel pump is cut off to prevent the fuel pump from burning out. The working principle of the mechanical flow switch is as follows: a baffle supported by a built-in spring impacts the medium as it flows through. The baffle compresses the spring, and when the flow rate reaches a set value, a microswitch is mechanically triggered.

[0005] However, mechanical flow switch solutions have installation direction requirements. They can be installed in horizontal pipes or vertical pipes with upward fluid flow, but not in pipes with downward fluid flow. When installed in an upward fluid flow pipe, the effect of gravity must also be considered; there are requirements for pipe diameter, as a mismatch between the flow switch and the pipe size can lead to inaccurate detection due to insufficient oil filling the pipe; they occupy a large amount of space, requiring the flow switch to be installed on a straight section of pipe with a straight stroke of at least 5 times the pipe diameter on both sides, wasting oil pipe; and the connection between the oil pipe and the flow switch requires an adapter and must be secured with clamps, see [reference needed]Figure 1 .

[0006] Furthermore, existing technologies can also utilize thermal conductivity flow switches to detect flow in pipelines. When no flow is detected (fuel pump running dry), the power to the fuel pump is cut off to prevent burnout. The working principle of a thermal conductivity flow switch is based on heat exchange. The probe incorporates a heating module and a heat-sensing module. The heat conduction of the flow switch is closely related to the flow rate of the medium. During measurement, the heating module emits heat. If there is no medium flowing in the pipeline, the heat received by the heat-sensing module is a fixed value. When there is medium flowing, the heat received by the heat-sensing module changes with the flow rate. The heat-sensing module converts this temperature difference signal into an electrical signal, which is then converted into a corresponding standard contact signal output by a processor.

[0007] However, it has requirements regarding the installation direction; please refer to the details for specific requirements. Figure 2 and Figure 3 Thermal conductivity flow switches operating for extended periods in pipelines with poor-quality oil can develop grease or rust buildup on the probe surface, causing it to malfunction. Changes in ambient temperature and oil temperature within the pipeline can also cause the internal setpoint to drift, making it unsuitable for environments with large temperature variations. Furthermore, the oil becomes viscous at low temperatures, leading to inaccurate probe readings and rendering the flow switch unusable in cold environments.

[0008] Therefore, we hereby propose a method, system, terminal equipment, storage medium, and control method for protecting a refueling pump from idling. Summary of the Invention

[0009] The main objective of this application is to provide a method, system, terminal equipment, storage medium, and control method for protecting a fuel pump from idling, aiming to solve the problems of existing fuel pump idling protection technologies in terms of reliability, real-time performance, cost, and prevention of malfunctions.

[0010] To achieve the above objectives, this application provides a method for protecting a fuel pump from idling, comprising the following steps: S1. A current detection device is installed in the power supply circuit of the fuel pump D to detect the working current of the fuel pump D in real time. S2. Set a current threshold, which is between the no-load operating current of the fuel pump D and the normal load operating current. S3. When the current detection device detects that the operating current is continuously lower than the current threshold for a preset delay time, a protection signal is generated. S4. Based on the protection signal, cut off the power supply circuit of the refueling pump D to achieve idling protection.

[0011] Preferably, the current detection device is a current relay KA, and the current threshold is achieved by setting the undercurrent action value of the current relay KA.

[0012] Preferably, in step S3, the preset delay time is implemented by a time relay KT; when the detected current of the current relay KA is lower than its undercurrent action value, its contacts actuate, triggering the time relay to start timing.

[0013] Preferably, the preset delay time is greater than the time required for the oil source to flow from the external pipeline to the refueling pump D, so as to avoid malfunction caused by the brief idling of the refueling pump D during the start-up phase.

[0014] Preferably, in step S4, cutting off the power supply circuit of the refueling pump D according to the protection signal specifically involves: When the refueling switch is closed, the contactor KM is energized, engages, and self-locks, and the refueling pump D starts working. The current relay KA is energized and begins to detect the circuit current; When the fuel pump D is in an idling state, its operating current is lower than the undercurrent action value of the current relay KA. Then the normally open contact of the current relay KA closes, energizing the coil of the time relay KT and starting the delay. If the operating current does not rise above the current threshold within the delay time of the time relay KT, the delay disconnect contact of the time relay KT will activate after the delay ends, cutting off the power supply to the coil of the contactor KM and causing the refueling pump D to stop working.

[0015] Preferably, the operating ambient temperature range of the current relay KA is -40℃ to +85℃.

[0016] Preferably, the rated power of the fuel pump D is 200W and the rated voltage is 24V; its idling current is about 2A and its normal load current is about 7-8A, and the current threshold is set to 5A.

[0017] To achieve the above objectives, this application provides a refueling pump idling protection system based on any of the above methods, comprising: a refueling pump D, wherein the positive terminal of the refueling pump D is connected to a positive power supply through the main contact of contactor KM and control button QF, and the negative terminal of the refueling pump D is connected to a negative power supply. It also includes a starting circuit and an idling detection circuit. The starting circuit includes a refueling switch SA, a coil of contactor KM, and a delayed-break contact of time relay KT. One end of the refueling switch SA is connected to a positive power supply, and the other end is connected to one end of the coil of contactor KM. The other end of the coil of contactor KM is connected to one end of the delayed-break contact of time relay KT, and the other end of the delayed-break contact of time relay KT is connected to a negative power supply. When the refueling switch SA is closed, the coil of contactor KM is energized, the main contacts of contactor KM close, and the refueling pump D starts running. Simultaneously, the delayed-break contact of time relay KT is normally closed, maintaining circuit continuity. The idling detection circuit includes coils for a current relay KA and a time relay KT. The coil of the current relay KA is connected in series in the main circuit of the fuel pump D to detect the operating current of the fuel pump D. One end of the coil of the time relay KT is connected to the positive power supply, and the other end is connected to the negative power supply through the normally closed contact of the current relay KA. When the fuel pump D is idling, the operating current is lower than the set value, the coil of the current relay KA is released, its normally closed contact is closed, and the coil of the time relay KT is energized to start timing. After the timing ends, the delayed disconnect contact of the time relay KT cuts off the power supply to the coil of the contactor KM in the first protection control circuit, the contactor KM is released, and the fuel pump D stops running, realizing idling protection.

[0018] To achieve the above objectives, this application provides a terminal device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the computer program is executed by the processor, it implements the steps of the above-described method for protecting a refueling pump from idling.

[0019] To achieve the above objectives, this application provides a readable storage medium storing a computer program, which, when executed by a processor, implements the steps of the above-described method for protecting a refueling pump from idling.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: By monitoring the operating current of the fuel pump in real time, this invention can sensitively identify the idling state, as the operating current during idling is significantly lower than the normal load operating current. Simultaneously, by setting a current threshold between the idling current and the normal load current, false judgments of critical states are avoided.

[0021] The introduction of a "preset delay time" mechanism ensures that protection is only triggered when the operating current remains below the current threshold for the specified delay time. This effectively avoids malfunctions caused by brief idling of the refueling pump during startup or when there is a small amount of medium in the pipeline, thus improving the stability and reliability of the system.

[0022] Once it is confirmed that the fuel pump is running dry, the system immediately cuts off its power supply circuit, which can stop the dry running in time. This avoids wear, overheating or even damage to the fuel pump caused by prolonged dry running, significantly extends the service life of the fuel pump, reduces maintenance costs and eliminates potential safety hazards.

[0023] Detection is achieved by utilizing changes in current in the power circuit, using conventional electrical components such as current relays and time relays. Compared to level switches or flow sensors, its system structure is simpler, and its deployment and maintenance costs are lower, making it more economical.

[0024] It can be applied to various models and power of fuel pumps. The current threshold and delay time can be adjusted according to the idling and load current characteristics of the specific pump, which has good versatility and promotion value. Attached Figure Description

[0025] Figure 1 This is a diagram showing the installation dimensions required for mechanical flow switches in the existing technology. Figure 2 This is a schematic diagram of a thermal conductivity flow switch in the prior art. Figure 3 The diagram shows the installation requirements for thermal conductivity flow switches in the existing technology. Figure 4 This is a circuit diagram of a refueling pump idling protection system according to an embodiment of this application; Figure 5 This is a schematic block diagram of the internal structure of a terminal device according to an embodiment of this application.

[0026] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0027] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0028] Furthermore, the use of terms such as "first" and "second" in this application is for descriptive purposes only (e.g., to distinguish identical or similar elements) and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed in this application.

[0029] This invention provides a method for protecting a fuel pump from idling. By monitoring the fuel pump's operating current in real time and combining this monitoring with a current threshold and a preset delay time, the power supply to the fuel pump can be effectively cut off, preventing it from idling for extended periods. Specifically, it includes the following steps: S1. A current detection device is installed in the power supply circuit of the fuel pump D to detect the operating current of the fuel pump D in real time.

[0030] Specifically, in step S1, in order to obtain the real-time operating status of the fuel pump D, a current detection device needs to be connected in series in its main power supply circuit. This current detection device can be of various types, such as a current transformer with measuring instruments, a current sensor, or a relay with current detection function. Its core function is to accurately and in real-time collect the current signal flowing through the fuel pump D for subsequent judgment.

[0031] S2. Set a current threshold, which is between the idling current of the fuel pump D and the normal load current.

[0032] Specifically, the operating current of fuel pump D in idle state is typically much lower than its operating current under normal load (i.e., normal fuel delivery). For example, when fuel pump D has a rated power of 200W and a rated voltage of 24V, its idle operating current may be approximately 2A, while its normal load operating current is approximately 7-8A. To accurately distinguish between these two operating states, a current threshold needs to be set. This current threshold should be greater than the idle operating current but less than the normal load operating current, ensuring that the operating current quickly exceeds this threshold after fuel pump D begins to operate under load, while remaining significantly lower than this threshold during idle. For example, in this case, this current threshold could be set to 5A. This threshold can be finely adjusted through experimentation or based on empirical values ​​to achieve the best differentiation effect.

[0033] S3. When the current detection device detects that the operating current is continuously lower than the current threshold for a preset delay time, a protection signal is generated.

[0034] Specifically, when fuel pump D starts, the fuel line may not be fully filled, resulting in a brief idling period; or during delivery, short-term air bubbles or flow interruptions may occur in the fuel line, causing a temporary decrease in operating current. Immediate protection would cause frequent malfunctions, affecting normal refueling operations. Therefore, a "preset delay time" is introduced. Only when the detected operating current remains below a set current threshold, and this low current state persists for a preset delay time (e.g., several seconds or tens of seconds), is fuel pump D considered to be in a prolonged idling state, and a protection signal is generated. This preset delay time should be greater than the time required for fuel to flow from the external pipeline to fuel pump D to ensure that the brief idling during startup does not trigger protection.

[0035] S4. Based on the protection signal, disconnect the power supply circuit of the fuel pump D to achieve idling protection. Once the protection signal is generated, the system will immediately act to cut off the power supply to the fuel pump D. This is usually achieved through a contactor or circuit breaker in the control circuit, isolating the fuel pump D from the power supply and stopping its operation. This effectively prevents the fuel pump D from running in an idling state for a long time, thereby protecting the equipment from damage.

[0036] In a preferred embodiment, please refer to [reference needed]. Figure 2 The current detection device is a current relay KA. The current relay KA can be directly connected in series in the main circuit of the fuel pump D to detect the circuit current. The current threshold can be set by setting an undercurrent trip value for the current relay KA. When the current flowing through the current relay KA is lower than its set undercurrent trip value, the internal contacts of the current relay KA will actuate. This method is simple, reliable, and inexpensive.

[0037] In another preferred embodiment, in step S3, the preset delay time is implemented by a time relay KT. When the detected current of the current relay KA is lower than its undercurrent action value, its internal contacts actuate (e.g., when a normally open contact is used, the contact closes; when a normally closed contact is used, the contact opens), triggering the time relay KT to start timing. The time relay KT then begins to delay after receiving the trigger signal. Only after the delay time has expired will its own delay contact actuate, thereby generating a protection signal.

[0038] In a further embodiment, the preset delay time should be greater than the time required for the oil to flow from the external pipeline to the refueling pump D. This time needs to be measured or estimated based on factors such as the actual pipeline length, oil viscosity, and pump suction head. By setting this time appropriately, malfunctions caused by brief idling during the start-up phase of the refueling pump D can be effectively avoided, ensuring smooth refueling.

[0039] Furthermore, in step S4, the specific implementation process of cutting off the power supply circuit of the refueling pump D according to the protection signal can be as follows: Assume the system includes a contactor KM that controls the start and stop of the fuel pump D, and a fuel switch SA.

[0040] When the refueling switch SA is closed, the coil of contactor KM is energized and latches itself, and its main contacts close, causing the refueling pump D to start working.

[0041] The current relay KA is energized and begins to detect the circuit current. At this time, the coil of the current relay KA is connected in series in the power supply circuit of the fuel pump D to monitor the operating current in real time.

[0042] When the fuel pump D is idling and its operating current is lower than the undercurrent tripping value of the current relay KA, the normally open contact of the current relay KA closes (or the normally closed contact opens), energizing the coil of the time relay KT and initiating a delay. Here, the closing of the normally open contact transmits a signal to the start terminal of the time relay KT.

[0043] If the operating current does not rise above the current threshold during the delay period of the time relay KT (i.e., the fuel pump D continues to run idle), the time-delay disconnect contact of the time relay KT will activate after the delay ends, cutting off the power supply to the coil of the contactor KM.

[0044] When the contactor KM coil is de-energized and its main contacts open, the refueling pump D stops working, thus achieving idling protection.

[0045] If, during the delay period of the time relay KT, the operating current of the fuel pump D rises and exceeds the current threshold (for example, fuel has been supplied normally), the current relay KA will release (its normally open contact opens or its normally closed contact closes), the coil of the time relay KT will be de-energized, the timing will stop and reset, the protection action will be canceled, and the fuel pump D will continue to work normally.

[0046] In another preferred embodiment, to ensure stable system operation under various environments, the operating temperature range of the current relay KA can be designed to be a wide range, such as -40℃ to +85℃. This can adapt to application requirements under different regional and climatic conditions, improving the reliability and adaptability of the system.

[0047] In a specific application example, the fuel pump D has a rated power of 200W and a rated voltage of 24V. Actual testing shows that its idle current is approximately 2A, and its normal load current is approximately 7-8A. Based on these parameters, the current threshold can be set to 5A. This 5A threshold falls precisely between the idle current (2A) and the normal load current (7-8A), effectively distinguishing between the two states.

[0048] This invention also provides a refueling pump idling protection system based on the above method. Please refer to [link / reference]. Figure 4 The system includes: Fuel pump D: The positive terminal of fuel pump D is connected to the positive power supply +V through the main contact of contactor KM and control button QF, and the negative terminal of fuel pump D is connected to the negative power supply -V.

[0049] In addition, the system also includes a startup circuit and an idle detection circuit.

[0050] Starting circuit: The starting circuit includes a refueling switch SA, a coil of contactor KM, and a time-delayed disconnect contact of time relay KT. Specifically, one end of the refueling switch SA is connected to the positive power supply +V, and the other end is connected to one end of the coil of contactor KM; the other end of the coil of contactor KM is connected to one end of the time-delayed disconnect contact of time relay KT, and the other end of the time-delayed disconnect contact of time relay KT is connected to the negative power supply -V.

[0051] When the refueling switch SA is closed, the coil of contactor KM is energized and its main contacts close, starting the refueling pump D. During this process, the time-delayed disconnecting contact of the time relay KT is normally closed (i.e., when the idling protection is not triggered) to keep the starting circuit conducting, ensuring that the coil of contactor KM is continuously energized.

[0052] Idle idling detection circuit: The idling detection circuit includes coils for a current relay KA and a time relay KT. Specifically, the coil of the current relay KA is connected in series in the main circuit of the fuel pump D to detect the operating current of the fuel pump D in real time. One end of the coil of the time relay KT is connected to the positive power supply +V, and the other end is connected to the negative power supply -V through the normally closed contact of the current relay KA.

[0053] Its protection principle is as follows: When the fuel pump D is running normally, the current is greater than the undercurrent trip value of the current relay KA. The coil of the current relay KA is energized and its normally closed contact is in the open state, so the coil of the time relay KT is not energized.

[0054] When the fuel pump D is idling, the operating current is lower than the undercurrent trip value of the current relay KA. At this time, the coil of the current relay KA is de-energized and releases, and its normally closed contact closes immediately. Due to the closure of the normally closed contact, the coil of the time relay KT is energized and begins the delay timing.

[0055] If the fuel pump D continues to run idle, when the time relay KT finishes timing, its delayed disconnect contact will activate (i.e., change from a closed state to an open state), cutting off the power supply to the contactor KM coil in the starting circuit. The contactor KM coil is de-energized and releases, its main contacts open, thereby stopping the fuel pump D and achieving idling protection.

[0056] If the operating current of the fuel pump D returns to its normal value during the delay period of the time relay KT, the coil of the current relay KA will be energized again, its normally closed contact will open, the coil of the time relay KT will be de-energized, the timing will be reset, the protection process will be stopped, and the fuel pump D will continue to operate normally.

[0057] Furthermore, this application embodiment also provides a terminal device, the internal structure of which can be as follows: Figure 5 As shown, the terminal device includes a processor, memory, communication interface, and database connected via a system bus. The processor provides computing and control capabilities. The terminal device's memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores the operating system, computer programs, and database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The terminal device's database stores data called by the computer programs. The terminal device's communication interface is used for data communication with external terminals. The terminal device's input device receives signals from external devices. When the computer program is executed by the processor, it implements a fuel pump idling protection method as described in the above embodiment.

[0058] Those skilled in the art will understand that Figure 5 The structure shown is merely a block diagram of a portion of the structure related to the solution of this application, and does not constitute a limitation on the terminal device on which the solution of this application is applied.

[0059] Furthermore, this application also proposes a readable storage medium comprising a computer program, which, when executed by a processor, implements the steps of the fuel pump idling protection method described in the above embodiments. It is understood that the readable storage medium in this embodiment can be a volatile readable storage medium or a non-volatile readable storage medium.

[0060] Those skilled in the art will understand that implementing all or part of the processes in the above-described fuel pump idling protection methods can be accomplished by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments of the above-described fuel pump idling protection methods. Any references to memory, storage, databases, or other media used in this application and in the embodiments can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual-speed SDRAM (SSRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0061] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, apparatus, article, or fuel pump idling protection method 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, apparatus, article, or fuel pump idling protection method. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, apparatus, article, or fuel pump idling protection method that includes that element.

[0062] The above description is only a preferred embodiment of this application and does not limit the patent scope of this application. Any equivalent structural or procedural changes made based on the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A method for protecting a fuel pump from dry running, characterized in that, Includes the following steps: S1. A current detection device is installed in the power supply circuit of the fuel pump D to detect the working current of the fuel pump D in real time. S2. Set a current threshold, which is between the no-load operating current of the fuel pump D and the normal load operating current. S3. When the current detection device detects that the operating current is continuously lower than the current threshold for a preset delay time, a protection signal is generated. S4. Based on the protection signal, cut off the power supply circuit of the refueling pump D to achieve idling protection.

2. The method for protecting a refueling pump from idling according to claim 1, characterized in that, The current detection device is a current relay KA, and the current threshold is achieved by setting the undercurrent action value of the current relay KA.

3. The method for protecting a refueling pump from idling according to claim 2, characterized in that, In step S3, the preset delay time is implemented by the time relay KT; when the detected current of the current relay KA is lower than its undercurrent action value, its contacts are activated, triggering the time relay to start timing.

4. The method for protecting a refueling pump from idling according to claim 3, characterized in that, The preset delay time is greater than the time required for the oil source to flow from the external pipeline to the fuel pump D, so as to avoid malfunction caused by the brief idling of the fuel pump D during the start-up phase.

5. The method for protecting a refueling pump from idling according to claim 1, characterized in that, In step S4, cutting off the power supply circuit of the refueling pump D according to the protection signal specifically involves: When the refueling switch is closed, the contactor KM is energized, engages, and self-locks, and the refueling pump D starts working. The current relay KA is energized and begins to detect the circuit current; When the fuel pump D is in an idling state, its operating current is lower than the undercurrent action value of the current relay KA. Then the normally open contact of the current relay KA closes, energizing the coil of the time relay KT and starting the delay. If the operating current does not rise above the current threshold within the delay time of the time relay KT, the delay disconnect contact of the time relay KT will activate after the delay ends, cutting off the power supply to the coil of the contactor KM and causing the refueling pump D to stop working.

6. The method for protecting a refueling pump from idling according to claim 5, characterized in that, The operating temperature range of the current relay KA is -40℃ to +85℃.

7. The method for protecting a refueling pump from idling according to claim 1, characterized in that, The rated power of the fuel pump D is 200W, and the rated voltage is 24V; its idling current is about 2A, and its normal load current is about 7-8A. The current threshold is set to 5A.

8. A refueling pump idling protection system based on any one of claims 1-7, comprising: A fuel pump D is provided, with its positive terminal connected to a positive power supply via the main contacts of contactor KM and control button QF, and its negative terminal connected to a negative power supply. The system is characterized by further including a starting circuit and an idling detection circuit. The starting circuit includes a fuel switch SA, a coil of contactor KM, and a delayed-open contact of time relay KT. One end of the fuel switch SA is connected to the positive power supply, and the other end is connected to one end of the coil of contactor KM. The other end of the coil of contactor KM is connected to one end of the delayed-open contact of time relay KT, and the other end of the delayed-open contact of time relay KT is connected to the negative power supply. When the fuel switch SA is closed, the coil of contactor KM is energized, the main contacts of contactor KM close, and the fuel pump D starts operating. Simultaneously, the delayed-open contact of time relay KT is normally closed, maintaining circuit continuity. The idling detection circuit includes coils for a current relay KA and a time relay KT. The coil of the current relay KA is connected in series in the main circuit of the fuel pump D to detect the operating current of the fuel pump D. One end of the coil of the time relay KT is connected to the positive power supply, and the other end is connected to the negative power supply through the normally closed contact of the current relay KA. When the fuel pump D is idling, the operating current is lower than the set value, the coil of the current relay KA is released, its normally closed contact is closed, and the coil of the time relay KT is energized to start timing. After the timing ends, the delayed disconnect contact of the time relay KT cuts off the power supply to the coil of the contactor KM in the first protection control circuit, the contactor KM is released, and the fuel pump D stops running, realizing idling protection.

9. A terminal device, characterized in that, The terminal device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the computer program is executed by the processor, it implements the steps of the fuel pump idling protection method as described in any one of claims 1 to 7.

10. A readable storage medium, characterized in that, The readable storage medium stores a computer program that, when executed by a processor, implements the steps of the fuel pump idling protection method as described in any one of claims 1 to 7.

Images