A control method and device for a low-pressure fuel pump

Abstract

One or more embodiments of the present specification provide a control method and device for a low-pressure fuel pump, the control method for the low-pressure fuel pump comprising: obtaining the fuel pump control mode information of the vehicle at the current moment; obtaining the fuel pump solenoid valve feedforward control duty cycle information at the current moment; obtaining the fuel pump solenoid valve PI control duty cycle information at the current moment; generating the fuel pump solenoid valve duty cycle comprehensive control information at the current moment according to the fuel pump control mode information of the vehicle at the current moment, the fuel pump solenoid valve feedforward control duty cycle information and the fuel pump solenoid valve PI control duty cycle information; controlling the low-pressure fuel pump according to the fuel pump solenoid valve duty cycle comprehensive control information. The method uses a variety of information such as the fuel pump solenoid valve feedforward control duty cycle and the fuel pump solenoid valve PI control duty cycle to control the vehicle, reasonably and accurately controls the fuel pump output pressure, thereby reducing energy consumption and improving fuel economy.

Description

Technical Field

[0001] One or more embodiments of the present specification relate to the technical field of fuel pump control, and in particular, to a control method and device for a low-pressure fuel pump. Background Art

[0002] At present, many traditional fuel and hybrid vehicles use relay switches to control the operation of the fuel pump, that is, the fuel pump is switched on and off according to the engine start state. Regardless of the engine load, the fuel pump output pressure must always be maintained at the fuel target pressure determined by the required fuel supply under the current engine speed and maximum load conditions. It cannot output a reasonable fuel pressure according to the actual working conditions, which will have an adverse impact on the vehicle's fuel consumption and emissions. Summary of the invention

[0003] In view of this, an object of one or more embodiments of the present specification is to provide a control method and device for a low-pressure fuel pump to overcome or alleviate at least one of the above-mentioned defects of the prior art.

[0004] Based on the above purpose, one or more embodiments of this specification provide a control method for a low-pressure fuel pump, and the control method for the low-pressure fuel pump includes:

[0005] Obtain the fuel pump control mode information of the vehicle at the current moment;

[0006] Obtain the current fuel pump solenoid valve feedforward control duty cycle information;

[0007] Get the current fuel pump solenoid valve PI control duty cycle information;

[0008] Generate the fuel pump solenoid valve duty cycle comprehensive control information at the current moment according to the fuel pump control mode information of the vehicle at the current moment, the fuel pump solenoid valve feedforward control duty cycle information and the fuel pump solenoid valve PI control duty cycle information;

[0009] The low-pressure fuel pump is controlled based on the comprehensive control information of the fuel pump solenoid valve duty cycle at the current moment.

[0010] Optionally, the obtaining of the fuel pump control mode information of the vehicle at the current moment includes:

[0011] Get fuel pump and vehicle information;

[0012] The working mode of the fuel pump is determined based on the obtained fuel and vehicle information.

[0013] Optionally, the obtaining of fuel pump and vehicle information includes:

[0014] Get battery voltage information;

[0015] Get the working status information of the fuel pump solenoid valve;

[0016] Get engine start information;

[0017] Get fuel pressure information;

[0018] Get fuel pump external request information.

[0019] Optionally, determining the working mode of the fuel pump according to the acquired fuel and vehicle information includes:

[0020] Determine whether any of the following conditions are met. If so, determine that the fuel pump operating mode is the default mode:

[0021] The battery voltage is lower than the lower limit.

[0022] The fuel pump solenoid valve is faulty.

[0023] The engine is in the process of starting.

[0024] Determine whether the following conditions are met at the same time. If so, the fuel pump operating mode is determined to be normal mode:

[0025] The battery voltage is higher than the lower limit.

[0026] The fuel pump solenoid valve is not faulty.

[0027] The engine is not in the process of starting.

[0028] The fuel pump pressure is greater than the limit value.

[0029] The fuel pump driver has no external request information.

[0030] The engine start completion time exceeds the threshold;

[0031] Determine that the following conditions are met at the same time. If so, the fuel pump operating mode is determined to be fixed duty cycle mode:

[0032] The battery voltage is higher than the lower limit.

[0033] The fuel pump solenoid valve is not faulty.

[0034] The engine is not in the process of starting.

[0035] The fuel pump pressure is less than the limit, or the fuel pump driver has an external request message, or the engine start completion time does not exceed the threshold.

[0036] Optionally, the obtaining of the fuel pump solenoid valve feedforward control duty cycle information at the current moment includes:

[0037] Obtain engine speed, fuel target pressure value, and feedforward duty cycle data table;

[0038] The feedforward control duty ratio of the fuel pump solenoid valve is obtained by querying the feedforward duty ratio data table according to the engine speed and the target fuel pressure value.

[0039] Optionally, obtaining the target fuel pressure value includes:

[0040] Obtain engine water temperature information, required fuel quantity information, fuel temperature information, engine speed information, and target pressure data table;

[0041] The target pressure data table is queried to obtain the target original value of the fuel pressure through the engine water temperature information, the required fuel quantity information, the fuel temperature information, and the engine speed information;

[0042] The original fuel pressure target value is processed by maximum and minimum limit values ​​to obtain the final fuel pressure target value.

[0043] Optionally, the obtaining of the fuel pump solenoid valve PI control duty cycle information at the current moment includes:

[0044] Obtain the fuel pressure target value and the actual fuel pump pressure value;

[0045] The PI control duty cycle of the fuel pump solenoid valve at the current moment is calculated based on the difference between the fuel pressure target value and the actual pressure value of the fuel pump.

[0046] Optionally, the step of obtaining the fuel pump solenoid valve PI control duty cycle information at the current moment further includes:

[0047] Obtain engine operating conditions, fuel pump pressure sensor information, and fuel pump solenoid valve operating status information:

[0048] Determine whether any of the following (1) or (2) is satisfied. If so, enter the I-term integral anti-saturation:

[0049] (1) The fuel pressure target value is greater than the actual fuel pressure value and the difference exceeds the limit value, and at the same time, the fuel pump control output duty cycle is less than the lower limit value and exceeds the time limit value;

[0050] (2) The actual fuel pressure value is greater than the target fuel pressure value and the difference exceeds the limit value, and at the same time, the fuel pump control output duty cycle is greater than the high limit value and exceeds the time limit value;

[0051] Determine whether the following conditions are met at the same time. If so, enter item I integration enable:

[0052] The engine is not in a fuel cut-off condition;

[0053] There is no fuel pump pressure sensor or fuel pump solenoid valve failure;

[0054] The I-term integral anti-saturation condition is not met.

[0055] Optionally, generating the fuel pump solenoid valve duty cycle comprehensive control information at the current moment according to the fuel pump control mode information of the vehicle at the current moment, the fuel pump solenoid valve feedforward control duty cycle information and the fuel pump solenoid valve PI control duty cycle information comprises:

[0056] Determine whether the working mode is the default mode. If so, the output duty cycle is zero;

[0057] Determine whether the working mode is the normal mode, if so, output the sum of the fuel pump solenoid valve feedforward control duty cycle and the fuel pump solenoid valve PI control duty cycle;

[0058] Determine whether the working mode is the fixed duty cycle mode. If so, output the fixed duty cycle of the fuel pump solenoid valve.

[0059] Another embodiment of the present specification provides a control device for a low-pressure fuel pump, comprising:

[0060] A control mode acquisition device, which acquires the fuel pump control mode information of the vehicle at the current moment;

[0061] A feedforward control duty ratio acquisition device, which acquires the feedforward control duty ratio information of the fuel pump solenoid valve at the current moment;

[0062] PI control duty cycle acquisition device, which acquires the PI control duty cycle information of the fuel pump solenoid valve at the current moment;

[0063] A duty cycle comprehensive control device, which generates the current fuel pump solenoid valve duty cycle comprehensive control information according to the current vehicle fuel pump control mode information, fuel pump solenoid valve feedforward control duty cycle information and fuel pump solenoid valve PI control duty cycle information;

[0064] The low-pressure fuel pump control device controls the low-pressure fuel pump according to the comprehensive control information of the fuel pump solenoid valve duty ratio at the current moment.

[0065] From the above description, it can be seen that a control method for a low-pressure fuel pump provided in one or more embodiments of the present specification provides a variety of control modes, which respectively use a variety of information such as feedforward control duty cycle, PI control duty cycle, etc. to control the vehicle, and reasonably and accurately control the fuel pump output pressure, thereby reducing energy consumption, thereby improving fuel economy, and making it easier for vehicles to meet the increasingly stringent passenger car fuel consumption and emission regulations. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] In order to more clearly illustrate one or more embodiments of the present specification or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only one or more embodiments of the present specification. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0067] Figure 1 A flowchart of a method for controlling a low-pressure fuel pump provided in one or more embodiments of this specification;

[0068] Figure 2 A flowchart of a method for determining a control mode according to one or more embodiments of this specification;

[0069] Figure 3 A schematic diagram of a flow chart of determining an enabling condition of an integral anti-saturation item provided in one or more embodiments of this specification;

[0070] Figure 4 A schematic diagram of a flow chart of a conditional judgment for enabling entry of an I-item integral provided in one or more embodiments of this specification;

[0071] Figure 5 A more specific schematic diagram of an electronic device is provided for one or more embodiments of this specification. DETAILED DESCRIPTION

[0072] In order to make the objectives, technical solutions and advantages of the present disclosure more clearly understood, the present disclosure is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0073] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in one or more embodiments of this specification should be understood by people with ordinary skills in the field to which this disclosure belongs. The "first", "second" and similar words used in one or more embodiments of this specification do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0074] Figure 1A flow chart of a method for controlling a low-pressure fuel pump provided in one embodiment of the present application;

[0075] like Figure 1 The control method of the low pressure fuel pump shown includes:

[0076] Obtain the fuel pump control mode information of the vehicle at the current moment;

[0077] Obtain the current fuel pump solenoid valve feedforward control duty cycle information;

[0078] Get the current fuel pump solenoid valve PI control duty cycle information;

[0079] Generate the fuel pump solenoid valve duty cycle comprehensive control information at the current moment according to the fuel pump control mode information of the vehicle at the current moment, the fuel pump solenoid valve feedforward control duty cycle information and the fuel pump solenoid valve PI control duty cycle information;

[0080] The low-pressure fuel pump is controlled based on the comprehensive control information of the fuel pump solenoid valve duty cycle at the current moment.

[0081] The control method of the low-pressure fuel pump provided in the present application provides a variety of control modes, which respectively use a variety of information such as feedforward control duty cycle, PI control duty cycle, etc. to control the vehicle, reasonably and accurately control the output pressure of the fuel pump, thereby reducing energy consumption, and then improving fuel economy, making it easier for the vehicle to meet the increasingly stringent passenger car fuel consumption and emission regulations.

[0082] In one embodiment, obtaining the fuel pump control mode information of the vehicle at the current moment includes:

[0083] Get fuel pump and vehicle information;

[0084] The working mode of the fuel pump is determined based on the obtained fuel and vehicle information.

[0085] This embodiment obtains fuel and vehicle information to comprehensively determine the vehicle's operating conditions, thereby determining the most suitable operating mode and further precisely controlling the vehicle.

[0086] In one embodiment, obtaining fuel pump and vehicle information includes:

[0087] Get battery voltage information;

[0088] Get the working status information of the fuel pump solenoid valve;

[0089] Get engine start information;

[0090] Get fuel pressure information;

[0091] Get fuel pump external request information.

[0092] Specifically, fuel pressure information can be obtained through the fuel pressure sensor voltage signal, CAN line fuel pressure signal, and LIN line fuel pressure signal. When the voltage signal is received directly, the voltage signal can be converted into a pressure signal according to the sensor characteristic slope and offset.

[0093] In one embodiment, determining the working mode of the fuel pump according to the acquired fuel and vehicle information includes:

[0094] Determine whether any of the following conditions are met. If so, determine that the fuel pump operating mode is the default mode:

[0095] The battery voltage is lower than the lower limit.

[0096] The fuel pump solenoid valve is faulty.

[0097] The engine is in the process of starting.

[0098] Determine whether the following conditions are met at the same time. If so, the fuel pump operating mode is determined to be normal mode:

[0099] The battery voltage is higher than the lower limit.

[0100] The fuel pump solenoid valve is not faulty.

[0101] The engine is not starting.

[0102] The fuel pump pressure is greater than the limit value.

[0103] The fuel pump driver has no external request information.

[0104] The engine start completion time exceeds the threshold;

[0105] Determine that the following conditions are met at the same time. If so, the fuel pump operating mode is determined to be fixed duty cycle mode:

[0106] The battery voltage is higher than the lower limit.

[0107] The fuel pump solenoid valve is not faulty.

[0108] The engine is not starting.

[0109] The fuel pump pressure is less than the limit, or the fuel pump driver has an external request message, or the engine start completion time does not exceed the threshold.

[0110] The step of "determining the working mode of the fuel pump based on the acquired fuel and vehicle information" in the present application is further elaborated in the following by way of example. It can be understood that this example does not constitute any limitation to the present application. Figure 2 A flowchart of a method for determining a control mode provided in one or more embodiments of this specification.

[0111] Reference Figure 2 , after the ECU is powered on or awakened, one or more of the following steps are performed in sequence:

[0112] Determine whether the battery voltage is higher than the lower limit, if not, determine that the fuel pump is in default mode; if yes, determine whether the fuel pump solenoid valve has no faults, if not, determine that the fuel pump is in default mode; if yes, determine whether the engine is not in the starting process, if not, determine that the fuel pump is in default mode; if yes, determine whether the fuel pump pressure is greater than the limit, if not, determine that the fuel pump is in fixed duty cycle mode; if yes, determine whether there is no external request for the fuel pump drive, if not, determine that the fuel pump is in fixed duty cycle mode; if yes, determine whether the engine starting completion time exceeds the threshold, if not, determine that the fuel pump is in fixed duty cycle mode; if yes, determine that the fuel pump is in normal mode.

[0113] In another embodiment, determining the working mode of the fuel pump according to the acquired fuel and vehicle information further includes:

[0114] It is determined whether the fuel pump is in the pre-pressure building stage. If so, it is determined that the fuel pump is in the fixed duty cycle mode.

[0115] Specifically, the pre-pressure building stage means: the ECU fuel pump control function is awakened (such as opening the driver's door) or the engine is not started when the ECU is powered on, and the fuel pressure is less than a certain limit.

[0116] In one embodiment, obtaining the fuel pump solenoid valve feedforward control duty cycle information at the current moment includes:

[0117] Obtain engine speed, fuel target pressure value, and feedforward duty cycle data table;

[0118] The feedforward control duty cycle of the fuel pump solenoid valve is obtained by querying the feedforward duty cycle data table through the engine speed and the fuel target pressure value.

[0119] The feedforward duty cycle data table presets the duty cycle information corresponding to the target pressure of the vehicle under different working conditions, and the fuel pump is controlled to output according to the target pressure through the duty cycle information.

[0120] In one embodiment, obtaining the target fuel pressure value includes:

[0121] Obtain engine water temperature information, required fuel quantity information, fuel temperature information, engine speed information, and target pressure data table;

[0122] The target pressure data table is queried through the engine water temperature information, the required fuel quantity information, the fuel temperature information, and the engine speed information to obtain the target original value of the fuel pressure;

[0123] The original fuel pressure target value is processed by maximum and minimum limit values ​​to obtain the final fuel pressure target value.

[0124] Specifically, the fuel temperature information can be obtained through the sensor fuel temperature voltage signal, CAN line fuel temperature signal, and LIN line fuel temperature signal. When the voltage signal is directly received, the voltage signal is converted into a temperature signal through the sensor characteristic chart. The collected original fuel temperature signal is low-pass filtered and the filtered fuel temperature signal is output. The low-pass filter formula is as follows:

[0125] Tfuel=Tfuel -1 +(Tfuel_raw-Tfuel -1 )*dt / T

[0126] Wherein, Tfuel is the fuel temperature after low-pass filtering, Tfuel-1 is the fuel temperature after the last low-pass filtering, Tfuel_raw is the fuel temperature before low-pass filtering, i.e. the original value of the fuel temperature (the above temperature units are all in °C), dt is the module calculation task cycle, and T is the low-pass filtering time constant (the above time units are all in s).

[0127] In one embodiment, querying the target pressure data table to obtain the target original value of the fuel pressure through the engine water temperature information, the required fuel quantity information, the fuel temperature information, and the engine speed information includes:

[0128] The target pressure data table includes a first target pressure data table (MAP1) and a second target pressure data table (MAP2);

[0129] By querying the first target pressure data table through the engine water temperature information and the required fuel quantity information;

[0130] querying a second target pressure data table through fuel temperature information and engine speed information;

[0131] The larger value of the above two query results is taken as the original target value of the fuel pressure.

[0132] In one embodiment, performing maximum and minimum value limiting processing on the original fuel pressure target value to obtain the final fuel pressure target value includes:

[0133] Determine whether the target original value of the fuel pressure is within the range from the maximum limit to the minimum limit, and if so, output the target original value of the fuel pressure as the target fuel pressure value;

[0134] If the original value of the pressure target is greater than the maximum limit, the output maximum limit is the fuel pressure target value;

[0135] If the pressure target original value is less than the minimum limit value, the output minimum limit value is the fuel pressure target value.

[0136] In one embodiment, the minimum limit can be set as a parameter, and the maximum limit is determined as follows:

[0137] Obtain required fuel quantity information and maximum limit data table;

[0138] According to the required fuel quantity information, query the maximum limit data table to obtain the corresponding pressure value;

[0139] Obtain the maximum pressure value that the low-pressure pipeline pressure limit valve can withstand;

[0140] The smaller of the two pressure values ​​mentioned above is the maximum limit.

[0141] In one embodiment, obtaining the target fuel pressure value further includes:

[0142] Get the fuel target pressure value at the last moment;

[0143] Determine whether the difference between the fuel target pressure value at this moment and the fuel target pressure value at the previous moment exceeds a threshold;

[0144] If yes, low-pass filtering is performed to obtain the final target fuel pressure value.

[0145] In one embodiment, the low-pass filtering calculation formula is as follows:

[0146] Pfueldes=Pfueldes -1 +(Pfueldes_raw-Pfueldes -1 )*dt / T

[0147] Among them, Pfueldes is the target fuel pressure after low-pass filtering, Pfueldes-1 is the target fuel pressure after the last low-pass filtering, Pfueldes_raw is the target fuel pressure before low-pass filtering, that is, the original value of the target fuel pressure (the above temperature units are all kpa), dt is the module calculation task cycle, and T is the low-pass filtering time constant. (The above time units are all s).

[0148] In one embodiment, obtaining the fuel pump solenoid valve PI control duty cycle information at the current moment specifically refers to:

[0149] Obtain the fuel pressure target value and the actual fuel pump pressure value;

[0150] The PI control duty cycle of the fuel pump solenoid valve at the current moment is calculated based on the difference between the fuel pressure target value and the actual pressure value of the fuel pump.

[0151] In one embodiment, calculating the PI control duty ratio of the fuel pump solenoid valve at the current moment according to the difference between the fuel pressure target value and the actual pressure value of the fuel pump includes:

[0152] Calculate the P term duty cycle P_out:

[0153] P_out=Dif*kp*Fac_Tfuel_P*Fac_Ubat_P

[0154] Calculate the I term duty cycle I_out:

[0155] I_in=Dif*ki*Fac_Tfuel_I*Fac_Ubat_I

[0156] I_out=I_ out -1 +I_in*dt / T

[0157] The symbols in the above formula represent the following meanings:

[0158] Dif: The difference between the fuel pressure target value and the actual fuel pump pressure value

[0159] kp: proportional term coefficient

[0160] ki: integral term coefficient

[0161] I _out -1 :Last value of duty cycle of item I

[0162] Fac_Tfuel_P: Fuel temperature proportional term correction factor

[0163] Fac_Tfuel_I: Fuel temperature integral correction factor

[0164] Fac_Ubat_P: Battery voltage proportional correction factor

[0165] Fac_Ubat_I: Battery voltage integral correction factor

[0166] dt: module calculation task cycle

[0167] T: low-pass filter time constant.

[0168] Figure 3 A schematic diagram of a flow chart for determining an enabling condition for integral anti-saturation of one or more embodiments of this specification.

[0169] Figure 4 A flowchart of one or more embodiments of the present specification providing I-item integration enabling entry into conditional judgment.

[0170] Reference Figure 3 and Figure 4 In one embodiment, calculating the PI control duty ratio of the fuel pump solenoid valve at the current moment according to the difference between the fuel pressure target value and the actual pressure value of the fuel pump also includes:

[0171] Determine whether any of the following (1) or (2) is satisfied. If so, enter the I-term integral anti-saturation:

[0172] (1) The fuel pressure target value is greater than the actual fuel pressure value and the difference exceeds the limit value, and at the same time, the fuel pump control output duty cycle is less than the lower limit value and exceeds the time limit value;

[0173] (2) The actual fuel pressure value is greater than the target fuel pressure value and the difference exceeds the limit value. At the same time, the fuel pump control output duty cycle is greater than the high limit value and exceeds the time limit value.

[0174] In this embodiment, the time limit can be set according to the situation, preferably 10 seconds to 1 minute;

[0175] The lower limit and upper limit refer to the ratio of the duty cycle, the unit is percentage, and can be set according to actual conditions.

[0176] Determine whether the following conditions are met at the same time. If so, enter item I integration enable:

[0177] The engine is not in a fuel cut-off condition;

[0178] There is no fuel pump pressure sensor or fuel pump solenoid valve failure;

[0179] The I-term integral anti-saturation condition is not met.

[0180] In one embodiment, generating the fuel pump solenoid valve duty cycle comprehensive control information at the current moment according to the fuel pump control mode information of the vehicle at the current moment, the fuel pump solenoid valve feedforward control duty cycle information and the fuel pump solenoid valve PI control duty cycle information includes:

[0181] Determine whether the working mode is the default mode. If so, the output duty cycle is zero;

[0182] Determine whether the working mode is the normal mode, if so, output the sum of the fuel pump solenoid valve feedforward control duty cycle and the fuel pump solenoid valve PI control duty cycle;

[0183] Determine whether the working mode is the fixed duty cycle mode. If so, output the fixed duty cycle of the fuel pump solenoid valve.

[0184] Specifically, the output duty cycle of zero described in this embodiment represents that the fuel pump is not controlled. At this time, the fuel pump always runs at the maximum pressure value like an ordinary fuel pump; the fixed duty cycle refers to a preset duty cycle value, which can be preset according to different vehicle operating conditions.

[0185] In one embodiment, controlling the low-pressure fuel pump according to the comprehensive control information of the duty cycle of the fuel pump solenoid valve at the current moment includes:

[0186] Determine whether it is in normal mode. If so, process the sum of the output feedforward control duty cycle and the PI control duty cycle as follows:

[0187] In order to make it clear, the sum of the feedforward control duty cycle and the PI control duty cycle is referred to as the normal mode duty cycle control information.

[0188] Determine whether the normal mode duty cycle control information is within a preset range, and if so, output the original value;

[0189] If the normal mode duty cycle control information is greater than the preset maximum value, the preset maximum value is output;

[0190] If the normal mode duty cycle control information is lower than the preset minimum value, the preset minimum value is output.

[0191] determining whether the change rate of the normal mode duty cycle control information is within a preset range, and if so, controlling the fuel pump according to the normal mode duty cycle control information;

[0192] If not, the fuel pump is controlled according to the duty cycle control information corresponding to the maximum change rate.

[0193] For example, the preset maximum rate of change is 0.7, and the duty cycle at the previous moment is 60%;

[0194] If the duty cycle at this moment is 90%, then the duty cycle change rate at this moment is (90%-60%) / 1=0.3, which is less than the preset maximum change rate at this moment, and the duty cycle information is output at 90%.

[0195] In one embodiment, calculating the normal mode duty cycle control information change rate includes:

[0196] Get the normal mode duty cycle control information at the previous moment;

[0197] The change is obtained by subtracting the normal mode duty cycle control information at the previous moment from the normal mode duty cycle control information at the current moment and dividing it by time.

[0198] In one embodiment, it is determined whether the working mode is the normal mode. If so, the sum of the fuel pump solenoid valve feedforward control duty cycle and the fuel pump solenoid valve PI control duty cycle is outputted, including:

[0199] Whether any of the following conditions are met, if so, only the fuel pump solenoid valve feedforward control duty cycle is output:

[0200] Determine whether the fuel pressure sensor is faulty;

[0201] Determine whether the fuel cut-off condition exists;

[0202] If not, the sum of the fuel pump solenoid valve feedforward control duty cycle and the fuel pump solenoid valve PI control duty cycle is output.

[0203] The control method of the low-pressure fuel pump provided in the present application comprehensively controls the working pressure of the fuel pump according to a variety of fuel information and vehicle information, and the control is more precise, which can effectively improve the fuel economy and power of the vehicle.

[0204] It should be noted that the method of one or more embodiments of this specification can be performed by a single device, such as a computer or server. The method of this embodiment can also be applied in a distributed scenario and completed by multiple devices cooperating with each other. In the case of such a distributed scenario, one of the multiple devices can only perform one or more steps in the method of one or more embodiments of this specification, and the multiple devices will interact with each other to complete the described method.

[0205] The above is a description of a specific embodiment of the specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0206] Another embodiment of the present specification provides a control device for a low-pressure fuel pump, comprising:

[0207] A control mode acquisition device, which acquires the fuel pump control mode information of the vehicle at the current moment;

[0208] A feedforward control duty ratio acquisition device, which acquires the feedforward control duty ratio information of the fuel pump solenoid valve at the current moment;

[0209] PI control duty cycle acquisition device, which acquires the PI control duty cycle information of the fuel pump solenoid valve at the current moment;

[0210] A duty cycle comprehensive control device generates the current fuel pump solenoid valve duty cycle comprehensive control information according to the current vehicle fuel pump control mode information, fuel pump solenoid valve feedforward control duty cycle information and fuel pump solenoid valve PI control duty cycle information;

[0211] The low-pressure fuel pump control device controls the low-pressure fuel pump according to the comprehensive control information of the fuel pump solenoid valve duty ratio at the current moment.

[0212] Figure 5A more specific schematic diagram of the hardware structure of an electronic device provided in this embodiment is shown, and the device may include: a processor 1010, a memory 1020, an input / output interface 1030, a communication interface 1040, and a bus 1050. The processor 1010, the memory 1020, the input / output interface 1030, and the communication interface 1040 are connected to each other through the bus 1050 in the device.

[0213] The processor 1010 can be implemented by a general-purpose CPU (Central Processing Unit), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of this specification.

[0214] The memory 1020 may be implemented in the form of ROM (Read Only Memory), RAM (Random Access Memory), static storage device, dynamic storage device, etc. The memory 1020 may store an operating system and other application programs. When the technical solutions provided in the embodiments of this specification are implemented by software or firmware, the relevant program codes are stored in the memory 1020 and are called and executed by the processor 1010.

[0215] The input / output interface 1030 is used to connect the input / output module to realize information input and output. The input / output module can be configured in the device as a component (not shown in the figure), or it can be externally connected to the device to provide corresponding functions. The input device may include a keyboard, a mouse, a touch screen, a microphone, various sensors, etc., and the output device may include a display, a speaker, a vibrator, an indicator light, etc.

[0216] The communication interface 1040 is used to connect a communication module (not shown) to realize communication interaction between the device and other devices. The communication module can realize communication through a wired mode (such as USB, network cable, etc.) or a wireless mode (such as mobile network, WIFI, Bluetooth, etc.).

[0217] The bus 1050 includes a path that transmits information between the various components of the device (eg, the processor 1010, the memory 1020, the input / output interface 1030, and the communication interface 1040).

[0218] It should be noted that, although the above device only shows the processor 1010, the memory 1020, the input / output interface 1030, the communication interface 1040 and the bus 1050, in the specific implementation process, the device may also include other components necessary for normal operation. In addition, it can be understood by those skilled in the art that the above device may also only include the components necessary for implementing the embodiments of the present specification, and does not necessarily include all the components shown in the figure.

[0219] Another embodiment of the present specification provides a computer-readable medium storing a computer program executable by an electronic device. When the computer program runs on the electronic device, the electronic device executes the steps of the low-pressure fuel pump control method provided in the embodiment of the present specification.

[0220] The computer-readable medium of this embodiment includes permanent and non-permanent, removable and non-removable media, and information storage can be implemented by any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, read-only compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device.

[0221] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present disclosure (including the claims) is limited to these examples. In line with the present disclosure, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of different aspects of one or more embodiments of the present specification as described above, which are not provided in detail for the sake of simplicity.

[0222] In addition, to simplify the description and discussion, and in order not to obscure one or more embodiments of the present specification, known power / ground connections to integrated circuit (IC) chips and other components may or may not be shown in the provided figures. In addition, the device may be shown in the form of a block diagram so as to avoid obscuring one or more embodiments of the present specification, and this also takes into account the fact that the details of the implementation of these block diagram devices are highly dependent on the platform on which one or more embodiments of the present specification will be implemented (i.e., these details should be fully within the scope of understanding of those skilled in the art). Where specific details (e.g., circuits) are set forth to describe exemplary embodiments of the present disclosure, it is apparent to those skilled in the art that one or more embodiments of the present specification may be implemented without these specific details or with variations in these specific details. Therefore, these descriptions should be considered illustrative rather than restrictive.

[0223] Although the present disclosure has been described in conjunction with specific embodiments of the present disclosure, many replacements, modifications and variations of these embodiments will be apparent to those skilled in the art from the foregoing description. For example, other memory architectures (e.g., dynamic RAM (DRAM)) may use the embodiments discussed.

[0224] One or more embodiments of this specification are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of one or more embodiments of this specification should be included in the scope of protection of this disclosure.

Claims

1. A method for controlling a low-pressure fuel pump, characterized in that: The control method of the low-pressure fuel pump comprises: Obtain the fuel pump control mode information of the vehicle at the current moment; Obtain the current fuel pump solenoid valve feedforward control duty cycle information; Get the current fuel pump solenoid valve PI control duty cycle information; Generate the fuel pump solenoid valve duty cycle comprehensive control information at the current moment according to the fuel pump control mode information of the vehicle at the current moment, the fuel pump solenoid valve feedforward control duty cycle information and the fuel pump solenoid valve PI control duty cycle information; Controlling the low-pressure fuel pump according to the comprehensive control information of the fuel pump solenoid valve duty cycle at the current moment; The step of obtaining the fuel pump control mode information of the vehicle at the current moment includes: Get fuel pump and vehicle information; Determine the working mode of the fuel pump based on the acquired fuel and vehicle information; Wherein, obtaining fuel and vehicle information includes: Get battery voltage information; Get the working status information of the fuel pump solenoid valve; Get engine start information; Get fuel pressure information; Get the external request information of the fuel pump; Wherein, judging the working mode of the fuel pump according to the acquired fuel and vehicle information includes: Determine whether any of the following conditions are met. If so, determine that the fuel pump operating mode is the default mode: The battery voltage is lower than the lower limit. The fuel pump solenoid valve is faulty. The engine is in the process of starting. Determine whether the following conditions are met at the same time. If so, the fuel pump operating mode is determined to be normal mode: The battery voltage is higher than the lower limit. The fuel pump solenoid valve is not faulty. The engine is not starting. The fuel pump pressure is greater than the limit value. The fuel pump driver has no external request information. The engine start completion time exceeds the threshold; Determine that the following conditions are met at the same time. If so, the fuel pump operating mode is determined to be fixed duty cycle mode: The battery voltage is higher than the lower limit. The fuel pump solenoid valve is not faulty. The engine is not starting. The fuel pump pressure is lower than the limit, or the fuel pump driver has an external request message, or the engine start completion time does not exceed the threshold; The generating of the fuel pump solenoid valve duty cycle comprehensive control information at the current moment according to the fuel pump control mode information of the vehicle at the current moment, the fuel pump solenoid valve feedforward control duty cycle information and the fuel pump solenoid valve PI control duty cycle information comprises: Determine whether the working mode is the default mode. If so, the output duty cycle is zero; Determine whether the working mode is the normal mode, if so, output the sum of the fuel pump solenoid valve feedforward control duty cycle and the fuel pump solenoid valve PI control duty cycle; Determine whether the working mode is a fixed duty cycle mode, and if so, output the fixed duty cycle of the fuel pump solenoid valve; The output duty cycle of zero represents that the fuel pump is not controlled and the fuel pump is always operated at the maximum pressure value.

2. The control method of the low-pressure fuel pump according to claim 1, characterized in that: The obtaining of the fuel pump solenoid valve feedforward control duty cycle information at the current moment includes: Obtain engine speed, fuel target pressure value, and feedforward duty cycle data table; The feedforward control duty ratio of the fuel pump solenoid valve is obtained by querying the feedforward duty ratio data table according to the engine speed and the target fuel pressure value.

3. The control method of the low-pressure fuel pump according to claim 2, characterized in that: The obtaining of the target fuel pressure value comprises: Obtain engine water temperature information, required fuel quantity information, fuel temperature information, engine speed information, and target pressure data table; The target pressure data table is queried to obtain the target original value of the fuel pressure through the engine water temperature information, the required fuel quantity information, the fuel temperature information, and the engine speed information; The original fuel pressure target value is processed by maximum and minimum limit values ​​to obtain the final fuel pressure target value.

4. The control method of the low-pressure fuel pump according to claim 3, characterized in that: The obtaining of the fuel pump solenoid valve PI control duty cycle information at the current moment includes: Obtain the fuel pressure target value and the actual fuel pump pressure value; The PI control duty cycle of the fuel pump solenoid valve at the current moment is calculated based on the difference between the fuel pressure target value and the actual pressure value of the fuel pump.

5. The control method of the low-pressure fuel pump according to claim 4, characterized in that: The step of obtaining the fuel pump solenoid valve PI control duty cycle information at the current moment also includes: Obtain engine operating conditions, fuel pump pressure sensor information, and fuel pump solenoid valve operating status information: Determine whether any of the following (1) or (2) is satisfied. If so, enter the I-term integral anti-saturation: (1) The fuel pressure target value is greater than the actual fuel pressure value and the difference exceeds the limit value, and at the same time, the fuel pump control output duty cycle is less than the lower limit value and exceeds the time limit value; (2) The actual fuel pressure value is greater than the target fuel pressure value and the difference exceeds the limit value, and at the same time, the fuel pump control output duty cycle is greater than the high limit value and exceeds the time limit value; Determine whether the following conditions are met at the same time. If so, enter item I integration enable: The engine is not in a fuel cut-off condition; There is no fuel pump pressure sensor or fuel pump solenoid valve failure; The I-term integral anti-saturation condition is not met.

6. A control device for a low-pressure fuel pump, characterized in that: include: A control mode acquisition device, which acquires the fuel pump control mode information of the vehicle at the current moment; A feedforward control duty ratio acquisition device, which acquires the feedforward control duty ratio information of the fuel pump solenoid valve at the current moment; PI control duty cycle acquisition device, which acquires the PI control duty cycle information of the fuel pump solenoid valve at the current moment; A duty cycle comprehensive control device, which generates the current fuel pump solenoid valve duty cycle comprehensive control information according to the current vehicle fuel pump control mode information, fuel pump solenoid valve feedforward control duty cycle information and fuel pump solenoid valve PI control duty cycle information; A low-pressure fuel pump control device controls the low-pressure fuel pump according to comprehensive control information of the fuel pump solenoid valve duty cycle at the current moment; Wherein, the control mode acquisition device is specifically used for: Get fuel pump and vehicle information; Determine the working mode of the fuel pump based on the acquired fuel and vehicle information; Wherein, the control mode acquisition device is specifically used for: Get battery voltage information; Get the working status information of the fuel pump solenoid valve; Get engine start information; Get fuel pressure information; Get the external request information of the fuel pump; Wherein, the control mode acquisition device is specifically used for: Determine whether any of the following conditions are met. If so, determine that the fuel pump operating mode is the default mode: The battery voltage is lower than the lower limit. The fuel pump solenoid valve is faulty. The engine is in the process of starting. Determine whether the following conditions are met at the same time. If so, the fuel pump operating mode is determined to be normal mode: The battery voltage is higher than the lower limit. The fuel pump solenoid valve is not faulty. The engine is not starting. The fuel pump pressure is greater than the limit value. The fuel pump driver has no external request information. The engine start completion time exceeds the threshold; Determine that the following conditions are met at the same time. If so, the fuel pump operating mode is determined to be fixed duty cycle mode: The battery voltage is higher than the lower limit. The fuel pump solenoid valve is not faulty. The engine is not in the process of starting. The fuel pump pressure is lower than the limit, or the fuel pump driver has an external request message, or the engine start completion time does not exceed the threshold; Wherein, the duty cycle comprehensive control device is specifically used for: Determine whether the working mode is the default mode. If so, the output duty cycle is zero; Determine whether the working mode is the normal mode, if so, output the sum of the fuel pump solenoid valve feedforward control duty cycle and the fuel pump solenoid valve PI control duty cycle; Determine whether the working mode is a fixed duty cycle mode, and if so, output the fixed duty cycle of the fuel pump solenoid valve; The output duty cycle of zero represents that the fuel pump is not controlled and the fuel pump is always operated at the maximum pressure value.

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