A control integrated fuel pump assembly and a control method thereof

Abstract

The application relates to the technical field of automobile electronic fuel supply, and particularly discloses a control integrated fuel pump assembly and a control method thereof, which comprises a total cost body, a fuel pump motor is integrated in the total cost body, a solid-state relay power switch module, a pressure sensor and a control unit are further integrated on the total cost body; the pressure sensor is integrated at a fuel outlet end of the total cost body and is used for collecting oil pressure signals of the fuel outlet in real time; the solid-state relay, the pressure sensor and the control unit are integrated in the fuel pump assembly, thereby replacing a traditional external mechanical relay and a decentralized control unit. The solid-state relay has no mechanical contact, is not prone to wear and tear and is resistant to vibration; in combination with real-time feedback of the internal pressure sensor, the control unit can generate a pulse width modulation signal to accurately perform closed-loop control on the fuel pump motor, so that the control response path is shortened, and the adjustment precision and response speed are improved.

Description

Technical Field

[0001] This invention relates to the field of automotive electronic fuel supply technology, specifically to a control integrated fuel pump assembly and its control method. Background Technology

[0002] Traditional automotive fuel pump assemblies typically control the fuel pump motor's on / off state via an external mechanical relay. Mechanical relays suffer from drawbacks such as large size, limited lifespan, easy contact wear, and susceptibility to poor contact in vibrating environments. While existing technologies utilize solid-state relays to supplement traditional relays for safety shut-off functions, or separate pressure sensors from the control unit for closed-loop control, none of these solutions integrate the solid-state relay and pressure sensor with the control unit within the fuel pump assembly.

[0003] Therefore, existing technical solutions suffer from problems such as dispersed components, complex wiring, long control response paths, and difficulty in further improving reliability. To address this, a control-integrated fuel pump assembly and its control method are proposed. Summary of the Invention

[0004] The main objective of this invention is to provide an integrated fuel pump assembly and its control method to solve the technical problems of dispersed fuel pump control components, slow control response, and insufficient reliability in the prior art, thereby achieving the technical effects of compact structure, precise control, and high reliability.

[0005] This invention provides the following technical solution: a control integrated fuel pump assembly, comprising a main body, wherein a fuel pump motor is integrated inside the main body, and a solid-state relay power switch module, a pressure sensor, and a control unit are also integrated on the main body; the pressure sensor is integrated at the fuel outlet end of the main body for real-time acquisition of the fuel outlet pressure signal; the control unit is electrically connected to the pressure sensor and the solid-state relay power switch module, the solid-state relay power switch module being connected in series between the vehicle power supply circuit and the fuel pump motor; the control unit is configured to acquire the real-time fuel pressure signal output by the pressure sensor, compare the real-time fuel pressure with a preset target fuel pressure to obtain the pressure deviation, generate a PWM pulse width modulation signal based on the pressure deviation and output it to the solid-state relay power switch module, and change the output power of the fuel pump motor by adjusting the on / off duty cycle of the solid-state relay to achieve local closed-loop precise control of fuel pressure.

[0006] As a preferred embodiment of the present invention, the control unit includes a microcontroller (MCU) and a power regulator; the microcontroller has a built-in ADC analog-to-digital conversion module and a PWM drive output module, which are used to acquire the analog voltage signal of the pressure sensor and generate a PWM modulation signal; the input terminal of the power regulator is connected to the vehicle's 9-16V on-board power supply, and outputs a stable 5V / 3.3V rated voltage to provide regulated power supply for the microcontroller and the pressure sensor.

[0007] As a preferred embodiment of the present invention, the pressure sensor is an analog oil pressure sensor.

[0008] As a preferred embodiment of the present invention, the solid-state relay power switch module consists of a series connection of low-side and high-side MOSFET power switches, or two MOSFET power switches of the same type connected in reverse series to form a contactless switch, and is equipped with freewheeling, clamping or overvoltage protection circuits to drive the inductive load of the fuel pump with high-frequency PWM switching.

[0009] As a preferred embodiment of the present invention, the total cost body also integrates a detection circuit, which includes at least one overcurrent detection circuit and an overtemperature detection circuit; the control unit is electrically connected to the detection circuit, and when an overcurrent or overtemperature abnormal signal is detected, the drive signal of the solid-state relay power switch module is directly cut off to achieve hardware fault protection.

[0010] Specifically, the overcurrent detection circuit collects the real-time current of the solid-state relay power switch module and the fuel pump motor power supply circuit through a sampling resistor.

[0011] Specifically, the over-temperature detection circuit has a built-in thermistor to collect the operating temperature of the power devices inside the main unit.

[0012] As a preferred embodiment of the present invention, the overall structure further includes a PCB mounting structure integrated on the flange. The mounting structure includes an electronic cavity disposed on the flange. The solid-state relay power switch module, control unit, and pressure sensor are all fixed in the electronic cavity. The electronic cavity is provided with matching seals and heat dissipation structures. The electronic cavity is arranged adjacent to the fuel outlet channel so that the detection end of the pressure sensor can directly contact the fuel medium to collect oil pressure.

[0013] A control method for an integrated fuel pump assembly, applied to the aforementioned fuel pump assembly, includes the following closed-loop control steps: S1, the control unit acquires the real-time fuel outlet pressure signal output by the pressure sensor; S2, the control unit acquires the target fuel pressure issued by the vehicle ECU, or calculates the dynamic target fuel pressure based on engine speed, throttle opening, injection pulse width, and battery voltage operating parameters; S3, the control unit calculates the pressure deviation between the real-time fuel pressure and the target fuel pressure; S4, the control unit calculates and outputs a corresponding duty cycle PWM signal to the solid-state relay power switch module based on the pressure deviation; S5, the control unit adjusts the average output power of the fuel pump motor by adjusting the on / off duty cycle of the solid-state relay power switch module; S6, the control unit continuously acquires and updates the real-time fuel pressure, continuously corrects the PWM duty cycle, and completes the closed-loop dynamic adjustment of the fuel pressure.

[0014] As a preferred embodiment of the present invention, the control unit can switch between multiple control operating modes; the voltage compensation control mode can be superimposed on a basic mode other than the protection shutdown mode; the voltage compensation output stops when the protection shutdown mode is triggered. Specifically, the basic modes include: pre-charge oil start mode, steady-state closed-loop control mode, rapid acceleration response mode, pressure maintenance and dead zone control mode, fault degradation oil supply mode, and protection shutdown mode; the superimposed correction mode includes voltage compensation control mode, which can be superimposed on any basic mode and take effect simultaneously. Among them, the protection shutdown mode has a higher priority than all other modes, and when triggered, it disables all other control logic.

[0015] As a preferred embodiment of the present invention, the control logic of each of the basic modes is as follows: Pre-charge mode: After the vehicle is powered on and woken up, the control unit outputs a fixed duty cycle of 70%–90% to drive the solid-state relay power switch module for 0.5s–2s to quickly establish pipeline oil pressure; after reaching the target oil pressure, it automatically switches to steady-state closed-loop mode; if the pre-charge timeout fails to establish pressure, it enters fault degradation mode; Steady-state closed-loop control mode: The PWM duty cycle is dynamically fine-tuned using a PID proportional-integral-derivative algorithm to eliminate steady-state oil pressure deviation in real time and maintain stable oil pressure; Rapid acceleration response mode: When a sudden change in throttle or injection pulse width is detected during rapid acceleration, a 10%–20% compensation duty cycle is superimposed on the steady-state basic duty cycle to improve the fuel supply response speed and suppress rapid acceleration oil pressure drop. The compensation lasts for 100ms to 1000ms before returning to steady state; Pressure holding and dead zone control mode: The dead zone threshold is 3kPa to 8kPa. When the difference between the real-time oil pressure and the target oil pressure is not greater than the dead zone threshold, the current PWM duty cycle is locked, and small adjustments are stopped to avoid frequent oil pressure fluctuations; Fault-degraded oil supply mode: When the pressure sensor signal is lost or the vehicle ECU communication is interrupted, closed-loop feedback is abandoned, and power supply is limited by a fixed safety duty cycle or a working condition lookup table method, and fault codes are reported simultaneously; Protection shutdown mode: When continuous overcurrent, motor stall, severe overheating of the assembly, or abnormally high oil pressure is detected, the PWM duty cycle is immediately set to 0, the solid-state relay power switch module is disconnected to cut off the oil pump power supply, and the fault lockout requires power-off restart to reset.

[0016] As a preferred embodiment of the present invention, the voltage compensation control mode logic is as follows: the control unit samples the vehicle battery voltage in real time, and when the voltage is lower than the 12V reference value, the PWM duty cycle is increased to compensate for power loss. When the voltage is higher than 12V, the duty cycle is reduced to limit the output power. The duty cycle is constrained by 0% to 100% or a safety limit, and voltage compensation stops when the protection shutdown mode is triggered.

[0017] As a preferred embodiment of the present invention, the control unit automatically switches between modes and states based on the vehicle's power-on status, engine operating conditions, oil pressure fluctuation status, abnormal pressure sensor signals, vehicle ECU communication failures, and current and temperature fault signals.

[0018] The present invention has the following beneficial effects: 1. In this invention, a solid-state relay, a pressure sensor, and a control unit are integrated inside the fuel pump assembly, replacing the traditional external mechanical relay and distributed control unit. The solid-state relay, as the main switching element, has no mechanical contacts, is not easily worn, and is vibration-resistant. Combined with real-time feedback from the internal pressure sensor, the control unit can generate pulse-width modulation signals to perform precise closed-loop control of the fuel pump motor, thereby shortening the control response path and improving adjustment accuracy and response speed.

[0019] 2. In this invention, by integrating overcurrent and overtemperature detection circuits and multiple control modes, the system can automatically switch control strategies according to different vehicle operating conditions, achieving safety protection or degraded operation in abnormal states. This reduces external components and complex wiring, resulting in a compact structure; improves the reliability and lifespan of fuel pump control; achieves precise fuel pressure regulation through closed-loop control, avoiding fuel waste; and enhances the system's adaptability to complex operating conditions and overall safety through multi-mode control. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the main structure of the overall cost body in this invention; Figure 2 This is a top view of the overall structure of the present invention; Figure 3 This is a block diagram showing the control working modes in this invention; Figure 4 This is a flowchart of the control steps in this invention; Figure 5 This is the control logic diagram in this invention.

[0021] In the diagram: 1. Total cost unit; 10. Fuel pump motor; 100. Electronic cavity; 2. Solid-state relay power switch module; 3. Pressure sensor. Detailed Implementation

[0022] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0023] This application can be applied to automotive fuel supply systems, especially for integrated control and drive scenarios of fuel pump assemblies, aiming to solve the problems of delayed oil pressure response, insufficient adjustment accuracy, and untimely fault protection caused by long control links in the prior art.

[0024] It should be noted that the following are explanations of some key terms appearing in this application: "Total cost component 1" refers to the main structural component of the fuel pump assembly, which serves as the physical support and integration basis for various internal components (such as motors, sensors, control modules, etc.).

[0025] "Fuel pump motor 10" refers to the drive motor integrated within the main unit 1, which is used to pump fuel from the fuel tank to the engine.

[0026] "Solid-state relay power switch module 2" refers to a contactless switch module composed of semiconductor power devices, which can respond to control signals to switch on and off at high frequency and is used to regulate the electrical energy supplied to the fuel pump motor 10.

[0027] "Control unit" refers to the electronic control core integrated in the main unit 1, which is responsible for acquiring signals, executing control logic and outputting drive signals. It may include microcontrollers (MCUs), power regulators, etc.

[0028] "Pressure sensor 3" refers to a device that converts fuel pressure into a measurable electrical signal, with its detection end directly or indirectly contacting the fuel medium.

[0029] "PWM pulse width modulation signal" refers to a digital modulation signal that adjusts the average output power by changing the pulse width.

[0030] The "PID proportional-integral-derivative algorithm" refers to a classic closed-loop control algorithm that adjusts the output by calculating the proportional, integral, and derivative components of the deviation to eliminate steady-state error.

[0031] like Figures 1 to 3 and Figure 5 As shown in the figure, this application embodiment provides a control integrated fuel pump assembly, which includes: Total cost 1; Fuel pump motor 10 is integrated inside the main body 1; Solid-state relay power switch module 2, pressure sensor 3, and control unit are integrated into the overall unit 1.

[0032] Specifically, pressure sensor 3 is integrated into the fuel outlet of the main unit 1 to collect the fuel pressure signal at the fuel outlet in real time; the control unit is electrically connected to pressure sensor 3 and solid-state relay power switch module 2 respectively, and solid-state relay power switch module 2 is connected in series between the vehicle power supply circuit and fuel pump motor 10; the control unit is configured to collect the real-time fuel pressure signal output by pressure sensor 3, compare the real-time fuel pressure with the preset target fuel pressure to obtain the pressure deviation, generate a PWM pulse width modulation signal based on the pressure deviation and output it to solid-state relay power switch module 2, and change the output power of fuel pump motor 10 by adjusting the duty cycle of solid-state relay, so as to realize local closed-loop precise control of fuel pressure.

[0033] In this embodiment, the aforementioned modules work collaboratively to form a highly integrated closed-loop control system. Pressure sensor 3 directly monitors the physical quantity of oil pressure at the fuel outlet and converts it into an electrical signal. The control unit acquires this signal and compares it with the target oil pressure in real time. Its internal logic operations directly generate a PWM signal to drive the solid-state relay power switch module 2. The solid-state relay power switch module 2 acts as a high-speed actuator, precisely controlling the average electrical energy transmitted to the fuel pump motor 10 based on the PWM duty cycle. Since the entire chain of signal acquisition, logic operation, and drive output is completed within the fuel pump assembly 1, the dependence on waiting for remote ECU commands is reduced, shortening the local closed-loop control path. The control unit adjusts the speed and torque of the fuel pump motor 10 through continuous calculation of pressure deviation and real-time correction of the PWM duty cycle, thereby precisely controlling the pumped fuel flow and pressure until the pressure deviation is eliminated, forming a complete, high-speed local closed-loop control network. This solves the problems of long control paths and lag in oil pressure response in traditional systems, achieving rapid, accurate, and localized oil pressure control.

[0034] Taking a specific application scenario as an example, during vehicle operation, the target oil pressure is set to 350 kPa based on engine operating conditions. When the engine suddenly enters acceleration mode, causing increased fuel consumption and the oil pressure to drop instantaneously to 330 kPa, the pressure sensor 3 integrated at the fuel outlet of the main unit 1 converts this pressure drop into a changing voltage signal within milliseconds. The microcontroller in the control unit acquires this signal in real time and immediately calculates a positive pressure deviation of 20 kPa. The control unit then executes its internal control algorithm, rapidly increasing the duty cycle of the output PWM signal, driving the MOSFET in the solid-state relay power switch module 2 to supply power to the fuel pump motor 10 for a longer conduction time. The motor speed increases accordingly, pumping out more fuel and causing the outlet oil pressure to rise rapidly. During this process, the control unit continuously reads new data from the pressure sensor 3. Once the oil pressure approaches 350 kPa, it gradually decreases the PWM duty cycle, eventually stabilizing it near the target value, thus completing the instantaneous and precise closed-loop compensation for the oil pressure drop.

[0035] In one embodiment, for the aforementioned control unit, to further optimize its performance and power supply stability, the control unit includes a microcontroller (MCU) and a power regulator. The microcontroller has a built-in ADC (Analog-to-Digital Converter) module and a PWM (Pulse Width Modulation) output module, used to acquire the analog voltage signal from the pressure sensor and generate a PWM modulation signal. The power regulator's input is connected to the vehicle's 9-16V on-board power supply, and it outputs a stable 5V / 3.3V rated voltage to provide regulated power to the microcontroller and pressure sensor 3. By integrating the ADC and PWM output modules into the microcontroller (MCU), the peripheral circuitry is greatly simplified. The entire link from signal acquisition to control output is completed within the MCU, physically shortening signal delay and avoiding interference from external circuits, thus helping to improve the accuracy of PWM signal generation. The power regulator converts the wide-ranging on-board power supply into a precise and stable low voltage, providing the microcontroller with a clean, noise-free power supply, ensuring the stability of its internal clock and logic operations. Simultaneously, it provides an independent and stable excitation voltage for the pressure sensor 3, ensuring that the accuracy of its output oil pressure signal is not affected by power supply voltage fluctuations, thereby guaranteeing the overall accuracy and robustness of the closed-loop control. As a specific implementation method, the power regulator can be a low dropout linear regulator with a high power supply rejection ratio (PSRR) to maximize the suppression of ripple and transient interference on the vehicle power supply bus.

[0036] In one embodiment, for the aforementioned pressure sensor 3 and solid-state relay power switch module 2, in order to further improve control response and durability, the pressure sensor 3 is an analog oil pressure sensor; the analog oil pressure sensor outputs an analog voltage that changes continuously with the oil pressure, and there is no sampling period or internal filtering delay as with digital sensors, which can transmit small and rapid changes in oil pressure to the control unit in real time.

[0037] The solid-state relay power switch module 2 consists of MOSFET power switches connected in series on the low and high sides, or two MOSFET power switches of the same type connected in reverse series to form a contactless switch. It is equipped with freewheeling, clamping, or overvoltage protection circuits to drive the inductive load of the fuel pump using high-frequency PWM switching. Compared to traditional electromagnetic relays, it eliminates lifespan limitations such as contact bounce, arc erosion, and mechanical fatigue, and can easily withstand high-frequency PWM switching operations of tens of thousands of hertz. This not only enables precise and continuous adjustment of the output power of the fuel pump motor 10, but also provides extremely high switching life and operational reliability due to its solid-state characteristics.

[0038] Furthermore, the solid-state relay power switch module 2 with contactless switching can effectively handle the back electromotive force generated by inductive loads such as fuel pump motors during rapid shutdown. It achieves energy freewheeling and clamping through internal parasitic diodes or matching drive logic, protecting the solid-state relay power switch module 2 itself from being damaged.

[0039] As a more specific implementation, the contactless solid-state relay power switch module 2 can reduce conduction losses and heat generation; the matching gate drive circuit can include a dedicated MOSFET driver chip, which receives low-voltage PWM logic signals from the microcontroller and converts them into gate drive signals with sufficient drive current and appropriate voltage levels to ensure that the MOSFET is turned on and off quickly and saturatedly.

[0040] In one embodiment, for the aforementioned total unit 1, in order to provide proactive hardware-level protection for the system, a detection circuit is also integrated within the total unit 1. This detection circuit includes at least one overcurrent detection circuit and an overtemperature detection circuit. The overcurrent detection circuit collects the real-time current of the power supply circuits of the solid-state relay power switch module 2 and the fuel pump motor 10 through a sampling resistor. The overtemperature detection circuit incorporates a thermistor to collect the operating temperature of the power devices inside the total unit 1. The control unit is electrically connected to the detection circuit. When an overcurrent or overtemperature abnormal signal is detected, the drive signal of the solid-state relay power switch module 2 is directly cut off, achieving hardware fault protection. By deploying overcurrent and overtemperature detection circuits within the total unit 1, a localized, fast-response protection network independent of the vehicle ECU is constructed. The overcurrent detection circuit uses a sampling resistor to linearly convert the power supply circuit current into a small voltage signal. This signal is captured by the ADC module of the control unit, which can monitor in real time whether the fuel pump motor 10 has abnormally high current conditions such as stall or short circuit. The over-temperature detection circuit uses a thermistor to sense the temperature of power devices, such as the solid-state relay power switch module 2, where heat generation is concentrated. When abnormal heat dissipation or excessive load causes a rapid temperature rise, the change in resistance quickly reflects the temperature status. When the control unit determines that the sampled current value exceeds the preset overcurrent threshold, or the detected temperature value exceeds the over-temperature threshold, its internal hardware protection logic will unconditionally set to the highest priority, immediately pulling the duty cycle of the PWM signal down to 0, forcibly cutting off the conduction of the solid-state relay power switch module 2, thereby cutting off the power supply to the fuel pump motor 10. This local protection mechanism does not require waiting for communication and arbitration from the ECU, has an extremely short response delay, and can complete fault isolation within microseconds to milliseconds, effectively preventing the fault from escalating and protecting key components such as the fuel pump motor 10 and the solid-state relay power switch module 2. As a more specific implementation, in the overcurrent detection circuit, the small voltage signal across the sampling resistor can first be amplified and filtered by an operational amplifier with a fixed gain before being sent to the microcontroller's ADC channel to improve the resolution and anti-interference capability of the current sampling.

[0041] In one embodiment, for the aforementioned total cost unit 1, to enhance integration and reliability, the total cost unit 1 also includes a PCB mounting structure integrated on the flange. The mounting structure includes an electronic cavity 100 mounted on the flange. The solid-state relay power switch module 2, control unit, and pressure sensor 3 are all fixed within the electronic cavity 100. The electronic cavity 100 is equipped with matching seals and a heat-dissipating structure. The electronic cavity 100 is arranged adjacent to the fuel outlet channel so that the detection end of the pressure sensor 3 can directly contact the fuel medium to collect fuel pressure. By uniformly placing these core electronic components—the solid-state relay power switch module 2, control unit, and pressure sensor 3—within a specially designed electronic cavity 100, a high degree of physical integration is achieved, shielding against external electromagnetic interference and mechanical shock. The seals ensure complete isolation between the inside of the electronic cavity 100 and harsh environments such as external fuel, water vapor, and dust, guaranteeing the working life and stability of the electronic components. Simultaneously, the heat-dissipating structure on the electronic cavity 100 efficiently dissipates the heat generated by the power devices to the surrounding environment, maintaining the internal temperature of the electronic cavity 100 within a safe range. The design of the electronic chamber 100 being adjacent to the fuel outlet channel allows the pressure sensor 3 to directly contact the flowing fuel medium, sensing the most realistic and dynamically responsive changes in fuel pressure. This eliminates the pressure signal transmission delay and distortion that may be caused by long pipelines between the fuel line and the sensor. This structural design physically supports the system's advantages of high precision, high reliability, and maintenance-free operation.

[0042] As a more specific implementation, the flange is a sealing flange on which the fuel pump assembly is mounted on the fuel tank. The electronic cavity 100 can be set on the upper surface of the flange and located on the outside of the fuel tank. The interface of the fuel outlet channel is also located on the flange. The two are integrally injection molded or assembled, with a compact structure, reducing connection points and potential leakage risks.

[0043] It should be noted that in some optional implementations, the specific driving method for the solid-state relay power switch module 2 can employ an isolated drive transformer or a high-speed optocoupler to achieve electrical isolation between the low-voltage side of the control unit and the high-voltage side of the power switch; alternatively, if the system power is relatively small, a non-isolated integrated high-side switch driving scheme can also be used. For the sampling resistor used for current sampling, its resistance value can be selected between 10 milliohms and 100 milliohms, using constantan or manganese bronze alloy materials to achieve low temperature drift and high-precision current detection. Heat dissipation can be achieved by filling the inside of the electronic cavity 100 with a high thermal conductivity insulating potting compound, efficiently conducting the heat from the power device to the metal casing of the electronic cavity 100 and then dissipating it into the environment. Furthermore, the flash memory of the microcontroller MCU can be pre-loaded with a factory-calibrated linearized lookup table for the pressure sensor 3 to compensate for nonlinear errors caused by individual sensor differences, further improving pressure acquisition accuracy.

[0044] like Figures 1 to 5 As shown in the embodiment of this application, a control method for an integrated fuel pump assembly is also provided, applied to the aforementioned fuel pump assembly, comprising the following closed-loop control steps: S1, the control unit acquires the real-time fuel outlet pressure signal output by the pressure sensor 3 in real time; S2, the target fuel pressure issued by the vehicle ECU is obtained, or the dynamic target fuel pressure is calculated based on engine speed, throttle opening, injection pulse width, and battery voltage operating parameters; S3, the pressure deviation between the real-time fuel pressure and the target fuel pressure is calculated; S4, based on the pressure deviation, a corresponding duty cycle PWM signal is output to the solid-state relay power switch module 2; S5, the average output power of the fuel pump motor is adjusted by the on / off duty cycle of the solid-state relay power switch module 2; S6, the real-time fuel pressure is collected and updated cyclically, and the PWM duty cycle is continuously corrected to complete the closed-loop dynamic adjustment of the fuel pressure.

[0045] In the method provided in this application embodiment, the above sequence of steps forms a complete and self-consistent autonomous control closed loop. Step S1 ensures that the control unit can constantly perceive the current oil pressure status; step S2 provides a flexible method for obtaining the target oil pressure, which can both obey vehicle control commands and estimate the demand based on local strategies when communication fails, using a preset safe target oil pressure lookup strategy to ensure the system's autonomous decision-making capability; step S3 quantifies the pressure regulation demand; steps S4 and S5 convert the results of digital calculations into physical execution actions; and step S6, through iterative iteration, makes the process a dynamic convergence process. This method requires no external controller intervention and is completed independently by the fuel pump assembly, greatly improving the response speed to dynamic operating conditions and the accuracy of oil pressure maintenance.

[0046] Taking a specific application scenario as an example, the vehicle ECU sends a command for a target oil pressure of 400 kPa to the control unit via the CAN bus, while the control unit collects a real-time oil pressure of 395 kPa from pressure sensor 3. The system enters S3, calculating a small negative deviation of -5 kPa; in S4, the proportional component of the PID algorithm within the control unit responds by slightly increasing the PWM duty cycle; in S5, the fuel pump motor 10 receives higher average power, its speed increases slightly, and the oil pressure begins to rise. In the next S6 cycle, the control unit detects that the oil pressure has risen to 400 kPa, the deviation returns to zero, and the PWM duty cycle remains at the current level, completing one closed-loop regulation for steady-state maintenance.

[0047] In one embodiment, in order to adapt to the fuel supply needs of the vehicle under all operating conditions, the control unit can switch between multiple control operating modes for the above method; the control operating modes include a basic mode and a superimposed correction mode. The basic modes include: pre-charge oil filling mode, steady-state closed-loop control mode, rapid acceleration response mode, pressure holding and dead zone control mode, fault degraded oil supply mode, and protection shutdown mode. The basic modes cover core states such as start-up, steady state, rapid acceleration, and fault, and the most suitable control strategy is adopted in each mode.

[0048] The superimposed correction mode includes a voltage compensation control mode, which can be superimposed on the basic mode except for the protection shutdown mode. The superimposed correction mode can be superimposed on the basic mode and actively compensate for the control deviation caused by battery voltage fluctuations without changing the main strategy. This reflects the high modularity and flexibility of the control architecture.

[0049] Among these, the protection shutdown mode has a higher priority than all other modes, and once triggered, it disables all other control logic. By decomposing a single control logic into multiple independent and targeted operating modes, the control strategy can be finely adapted to different operating scenarios. The protection shutdown mode has the highest priority; regardless of the current mode or the operation being performed, once triggered, it will unconditionally enforce power-off protection, reducing fault response latency and improving protection reliability from a software logic perspective.

[0050] In one embodiment, the control logic for the above basic mode is as follows: Pre-charge oil mode activation: After the vehicle is powered on and woken up, the control unit outputs a 70%–90% fixed duty cycle to drive the solid-state relay power switch module 2 for 0.5s–2s to quickly build up the pipeline oil pressure; after reaching the target oil pressure, it automatically switches to steady-state closed-loop mode; if the pre-charge timeout fails to build up pressure, it enters fault degradation mode. This mode simulates the "powerful" action of initial pressure building, with a brief high duty cycle open-loop drive that can quickly purge air from the pipeline, build up initial pressure, and shorten the start-up waiting time. An overdue exit mechanism and degradation path are set to prevent damage to the motor due to prolonged stalling when pressure is not built up for a long time.

[0051] Steady-state closed-loop control mode: A PID proportional-integral-derivative algorithm is used to dynamically fine-tune the PWM duty cycle, eliminating steady-state oil pressure deviations in real time and maintaining stable oil pressure. This is the most commonly used operating mode of the system. The proportional term in the PID algorithm quickly responds to deviations, the integral term eliminates long-term steady-state errors, and the derivative term suppresses oscillations. These three components work together to precisely lock the oil pressure at the target value.

[0052] Rapid Acceleration Response Mode: When a sudden acceleration condition is detected due to a change in throttle or injection pulse width, a 10%–20% compensation duty cycle is added to the steady-state duty cycle to improve fuel supply response speed and suppress fuel pressure drop during rapid acceleration. The compensation lasts for 100ms–1000ms before returning to steady state. This is a composite control combining feedforward and feedback. Before the steady-state closed-loop feedback regulation detects the fuel pressure drop caused by acceleration, this mode has already predicted the upcoming large fuel demand by detecting sudden changes in throttle or pulse width signals, and actively and instantaneously adds a compensation duty cycle to achieve proactive suppression of fuel pressure drop.

[0053] Pressure Holding and Dead Zone Control Mode: The dead zone threshold is 3kPa to 8kPa. When the difference between the real-time oil pressure and the target oil pressure is not greater than the dead zone threshold, the current PWM duty cycle is locked, and small adjustments are stopped to avoid frequent oil pressure fluctuations. This mode cleverly introduces a control insensitivity zone. When the oil pressure error is extremely small and has no impact on engine operation, the PWM output is forcibly frozen to avoid frequent motor speed adjustments caused by noise and minor disturbances. This not only reduces the power consumption and wear of the fuel pump but also eliminates micro-fluctuations in oil pressure, improving the stability of oil pressure control.

[0054] Fault-Degradation Fuel Supply Mode: When the pressure sensor 3 signal is lost or the vehicle ECU communication is interrupted, closed-loop feedback is abandoned, and power-limited fuel supply is adopted using a fixed safety duty cycle or a lookup table based on operating conditions, while simultaneously reporting fault codes. This mode is a fault-degradation operation strategy for the system under non-fatal faults. When core sensors or control command sources are lost, basic fuel supply can be maintained based on preset open-loop safety values, ensuring that the vehicle can still be driven to a repair shop in a limited state, rather than immediately stalling and breaking down.

[0055] Protection Shutdown Mode: Upon detecting continuous overcurrent, motor stall, severe assembly overheating, or abnormally high oil pressure, the PWM duty cycle is immediately set to 0, the solid-state relay power switch module 2 is disconnected to cut off the oil pump power supply, and the fault lockout requires a power-off restart to reset. This mode targets fatal faults that could cause permanent hardware damage, and its action is the last and most decisive. Setting the duty cycle to 0 is the fundamental means of cutting off energy, while the "fault lockout requires a power-off restart to reset" strategy prevents the system from repeatedly attempting to power on before the cause of the dangerous fault is identified, thus avoiding the escalation of the fault.

[0056] In one embodiment, the logic for the aforementioned superimposed correction mode, i.e., the voltage compensation control mode, is as follows: The control unit samples the on-board battery voltage in real time. When the voltage is lower than the 12V reference value, the PWM duty cycle is increased to compensate for power loss. When the voltage is higher than 12V, the duty cycle is decreased to limit the output power. The duty cycle is constrained by 0% to 100% or a safety limit, and voltage compensation stops when the protection shutdown mode is triggered. In closed-loop control, the goal is to control the oil pressure, and the control method is to output the PWM duty cycle. However, even if the duty cycle remains unchanged, the actual input voltage of the fuel pump motor 10 will still change with the fluctuation of the battery voltage, causing the output power and oil pressure to fluctuate accordingly. This mode directly samples the battery voltage and uses it as a feedforward quantity to perform reverse compensation on the PWM duty cycle. When the voltage is low, the duty cycle is increased to maintain the equivalent power supply energy; when the voltage is high, the duty cycle is decreased to stabilize the output and avoid overpower. This process is independent of the oil pressure closed loop, operates at extremely high speed, and can pre-correct the drive signal before the oil pressure is disturbed, greatly enhancing the output consistency and robustness of the system under different power conditions.

[0057] In summary, this application provides a control-integrated fuel pump assembly, including a main body 1, a fuel pump motor 10 integrated within the main body 1, a solid-state relay power switch module 2 integrated on the top of the main body 1, a pressure sensor 3, and a control unit, etc. Each module unit, through internal circuit connections and mechanical structure coupling, jointly realizes the various functions of the control method provided in this application. This highly integrated hardware structure corresponds to and supports the signal acquisition, local calculation, PWM power drive, and fault diagnosis and protection functions required in the method of this application, enabling all the above control steps and mode switching to be autonomously completed within a compact physical entity.

[0058] The integrated fuel pump assembly also integrates electronic control equipment. This electronic equipment includes at least a processor and a memory. The memory stores computer programs, and the processor calls and runs the computer programs stored in the memory to execute the control methods for the integrated fuel pump assembly as described above. The processor here can correspond to the microcontroller (MCU) in the above embodiments, which, through calculation and processing of stored instructions and data, realizes all functions such as oil pressure signal acquisition and processing, closed-loop control algorithms, operating mode scheduling, and fault protection logic.

[0059] The control unit for the integrated fuel pump assembly is also connected to a computer-readable storage medium storing a computer program. When executed by a processor, this program implements the steps of the control method for the integrated fuel pump assembly as described above. This storage medium can be the flash memory built into a microcontroller (MCU) or a separate EEPROM, Flash chip, etc., containing the firmware code that implements the entire control logic. The processor reads and executes this code to complete the entire control process from signal acquisition and analysis to drive output.

[0060] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A control integrated fuel pump assembly, characterized in that, The system includes a total cost unit (1), which integrates a fuel pump motor (10) and also integrates a solid-state relay power switch module (2), a pressure sensor (3) and a control unit. The pressure sensor (3) is integrated into the fuel outlet end of the main body (1) and is used to collect the oil pressure signal of the fuel outlet in real time. The control unit is electrically connected to the pressure sensor (3) and the solid-state relay power switch module (2), respectively. The solid-state relay power switch module (2) is connected in series between the vehicle power supply circuit and the fuel pump motor (10). The control unit is configured to collect the real-time oil pressure signal output by the pressure sensor (3), compare the real-time oil pressure with the preset target oil pressure to obtain the pressure deviation, generate a PWM pulse width modulation signal based on the pressure deviation and output it to the solid-state relay power switch module (2), and change the output power of the fuel pump motor (10) by adjusting the duty cycle of the solid-state relay to achieve local closed-loop precise control of fuel pressure.

2. The integrated fuel pump assembly according to claim 1, characterized in that, The control unit includes a microcontroller (MCU) and a power regulator; The microcontroller has a built-in ADC analog-to-digital converter module and a PWM drive output module, which are used to acquire the analog voltage signal from the pressure sensor and generate the PWM modulation signal. The input terminal of the power regulator is connected to the vehicle's 9-16V on-board power supply and outputs a stable 5V / 3.3V rated voltage to provide regulated power supply for the microcontroller and pressure sensor (3).

3. The integrated fuel pump assembly according to claim 1, characterized in that, The pressure sensor is an analog oil pressure sensor; The solid-state relay power switch module (2) consists of a series of low-side and high-side MOSFET power switches, or two MOSFET power switches of the same type connected in reverse series to form a contactless switch, and is equipped with freewheeling, clamping or overvoltage protection circuits to drive the fuel pump inductive load with high-frequency PWM switching.

4. The integrated fuel pump assembly according to claim 1, characterized in that, The total cost body (1) also integrates a detection circuit, which includes at least one overcurrent detection circuit and an overtemperature detection circuit; The overcurrent detection circuit collects the real-time current of the power supply circuit of the solid-state relay power switch module (2) and the fuel pump motor (10) through a sampling resistor; The over-temperature detection circuit has a built-in thermistor to collect the operating temperature of the power devices inside the main body (1); The control unit is electrically connected to the detection circuit. When an overcurrent or overtemperature abnormal signal is detected, the drive signal of the solid-state relay power switch module (2) is directly cut off to achieve hardware fault protection.

5. The integrated fuel pump assembly according to claim 1, characterized in that, The total cost unit (1) also includes a PCB mounting structure integrated on the flange. The mounting structure includes an electronic cavity (100) set on the flange. The solid-state relay power switch module (2), control unit, and pressure sensor (3) are all fixed in the electronic cavity (100). The electronic cavity (100) is provided with matching seals and heat dissipation structures. The electronic cavity (100) is arranged adjacent to the fuel outlet channel so that the detection end of the pressure sensor (3) can directly contact the fuel medium to collect oil pressure.

6. A control method for an integrated fuel pump assembly, applied to the fuel pump assembly according to any one of claims 1 to 5, characterized in that, The following closed-loop control steps are included: S1. The control unit collects the real-time oil pressure signal of the fuel outlet output by the pressure sensor (3) in real time. S2. Obtain the target oil pressure issued by the vehicle ECU, or calculate the dynamic target oil pressure based on engine speed, throttle opening, injection pulse width, battery voltage and operating parameters. S3. Calculate the pressure deviation between the real-time oil pressure and the target oil pressure; S4. Based on the pressure deviation calculation, output the corresponding duty cycle PWM signal to the solid-state relay power switch module (2). S5. Adjust the average output power of the fuel pump motor (10) by the on / off duty cycle of the solid-state relay power switch module (2); S6. Circularly collect and update real-time oil pressure, continuously correct the PWM duty cycle, and complete the closed-loop dynamic adjustment of oil pressure.

7. The control method for an integrated fuel pump assembly according to claim 6, characterized in that, The control unit can switch between multiple control operating modes; The control operating modes include a basic mode and a superimposed correction mode; The basic modes include: pre-charge oil charging mode, steady-state closed-loop control mode, rapid acceleration response mode, pressure holding and dead zone control mode, fault degradation oil supply mode, and protection shutdown mode; The superimposed correction mode includes a voltage compensation control mode, which can be superimposed on a basic mode other than the protection shutdown mode; when the protection shutdown mode is triggered, the voltage compensation output is stopped. Among them, the protection shutdown mode has a higher priority than all other modes, and when triggered, it disables all other control logic.

8. The control method for an integrated fuel pump assembly according to claim 7, characterized in that, The control logic for each of the basic modes is as follows: Start the pre-charge oil mode: After the vehicle is powered on and woken up, the control unit outputs a fixed duty cycle of 70% to 90% to drive the solid-state relay power switch module (2) for 0.5s to 2s to quickly build up the pipeline oil pressure; after the target oil pressure is reached, it automatically switches to the steady-state closed-loop mode; if the pressure is not built up after the pre-charge timeout, it enters the fault degradation mode; Steady-state closed-loop control mode: The PID proportional-integral-derivative algorithm is used to dynamically fine-tune the PWM duty cycle, eliminate the steady-state deviation of oil pressure in real time, and maintain stable oil pressure; Rapid acceleration response mode: When a sudden acceleration condition is detected due to a change in throttle or injection pulse width, a 10% to 20% compensation duty cycle is added to the steady-state duty cycle to improve the fuel supply response speed and suppress the drop in fuel pressure during rapid acceleration; the compensation lasts for 100ms to 1000ms before returning to steady state. Pressure holding and dead zone control mode: The dead zone threshold is 3kPa to 8kPa. When the difference between the real-time oil pressure and the target oil pressure is not greater than the dead zone threshold, the current PWM duty cycle is locked and small adjustments are stopped to avoid frequent fluctuations in oil pressure. Fault-degraded fuel supply mode: When the pressure sensor (3) signal is lost and the vehicle ECU communication is interrupted, the closed-loop feedback is abandoned, and the power supply is limited by a fixed safety duty cycle or working condition lookup table method, and the fault code is reported simultaneously. Protection shutdown mode: When a fault is detected such as continuous overcurrent, motor stall, severe overheating of the assembly, or abnormally high oil pressure, the PWM duty cycle is immediately set to 0, the solid-state relay power switch module (2) is disconnected, the oil pump power supply is cut off, and the fault lockout requires power off and restart to reset.

9. The control method for an integrated fuel pump assembly according to claim 7, characterized in that, The logic of the voltage compensation control mode is as follows: The control unit samples the vehicle battery voltage in real time. When the voltage is lower than the 12V reference value, it increases the PWM duty cycle to compensate for power loss. When the voltage is higher than 12V, it decreases the duty cycle to limit the output power. The duty cycle is constrained by 0% to 100% or a safety limit. When the protection shutdown mode is triggered, voltage compensation stops working.

10. The control method for an integrated fuel pump assembly according to claim 7, characterized in that, The control unit automatically switches between modes and state machines based on the vehicle's power-on status, engine operating conditions, oil pressure fluctuations, abnormal pressure sensor signals, vehicle ECU communication failures, and current / temperature fault signals.

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