Online controllable high-pressure common rail fuel injection electric control system

Abstract

The utility model discloses an electric control system for high-pressure common rail fuel injection of an aero-engine. The electric control system comprises a PID rail pressure control subsystem, a fuel injection control subsystem and a computer. The PID rail pressure control subsystem comprises a low-pressure oil way, an oil pump, a high-pressure oil way, a proportional electromagnetic valve, a power amplifier and a first single-chip microcomputer. The fuel injection control subsystem comprises a fuel injector, a drive circuit, a trigger module and a second single-chip microcomputer. In the PID rail pressure control subsystem, a low-pressure oil way, a proportional electromagnetic valve, an oil pump and a high-pressure oil way are sequentially connected, and the tail end of the high-pressure oil way is connected with an oil sprayer. In the fuel injection control subsystem, a trigger module transmits a trigger instruction to a second single-chip microcomputer, and a drive circuit is electrically connected with the second single-chip microcomputer and a fuel injector. The computer can control the first single-chip microcomputer and the second single-chip microcomputer respectively, and high-pressure common rail pressure maintenance and oil injection control are achieved in parallel.

Description

Technical Field

[0001] The utility model belongs to the technical field of internal combustion engines, and in particular relates to an electronic control system for high-pressure common rail fuel injection of diesel and aviation kerosene aviation engines. Background Art

[0002] Some existing carburetor aircraft engines have the problem of being unable to accurately control the amount and timing of fuel injection due to the limitations of the working principle of the carburetor. When the external working environment changes, the engine's fuel injection control cannot be adjusted in time. For example, when flying at high altitude, the decrease in intake pressure and temperature will cause the mixture entering the cylinder to be in a rich state. This will cause a series of problems, including incomplete engine combustion, power reduction, increased fuel consumption, and decreased combustion stability. These problems seriously threaten the reliability of small piston aircraft engines. In addition, the characteristics of aviation kerosene make it have a higher kinematic viscosity than gasoline, resulting in greater flow resistance and more difficult atomization. Therefore, solving the fuel supply and atomization problems of aviation kerosene is one of the important technical challenges of aviation kerosene piston engines.

[0003] The high-pressure common rail fuel injection electronic control system achieves highly accurate control of the fuel injection amount, injection timing and spray quality by digitizing and electronicizing the fuel supply process. Compared with the traditional fuel injection system, it introduces a common rail fuel supply pipeline to store the fuel at extremely high pressure in the common rail, and then accurately controls the fuel pressure and injection timing through an advanced electronic control unit to adapt to the engine requirements under different working conditions. For example, when an aircraft engine can fly at high altitudes, the electronic control unit can accurately correct the fuel injection amount according to changes in environmental conditions (including fluctuations in intake pressure and temperature), thereby avoiding problems that may be caused by the carburetor fuel supply method, such as incomplete combustion, reduced power performance, and even flameout in the air. This technology improves the atomization effect of the fuel and provides key support for the efficient, clean and low-noise operation of modern engines.

[0004] For this purpose, it is considered to provide an electronic control system for high-pressure common rail fuel injection of diesel and aviation kerosene aircraft engines. Utility Model Content

[0005] The utility model aims to solve the problem of inaccurate fuel supply of traditional carburetors and provides an electronic control system for high-pressure common rail fuel injection of diesel and aviation kerosene aircraft engines. The electronic control system has two subsystems, which are controlled by two single-chip microcomputers through computers respectively, and can realize high-pressure common rail pressure maintenance and fuel injection control in parallel.

[0006] The purpose of this utility model is achieved through the following technical solutions:

[0007] An electronic control system for high-pressure common rail fuel injection of an aircraft engine, comprising a PID rail pressure control subsystem, a fuel injection control subsystem and a computer; wherein the PID rail pressure control subsystem comprises a low-pressure oil circuit, an oil pump, a high-pressure oil circuit, a proportional solenoid valve, a power amplifier and a first single-chip microcomputer; the fuel injection control subsystem comprises a fuel injector, a drive circuit, a trigger module and a second single-chip microcomputer;

[0008] Among them, in the PID rail pressure control subsystem, the low-pressure oil circuit, the proportional solenoid valve, the oil pump, and the high-pressure oil circuit are connected in sequence, the end of the high-pressure oil circuit is connected to the injector, and the proportional solenoid valve is also electrically connected to the power amplifier;

[0009] A pressure sensor is arranged on the high-pressure oil circuit, and is used to transmit the current rail pressure value to the first single-chip microcomputer in real time; the first single-chip microcomputer is electrically connected to the pressure sensor and the power amplifier;

[0010] In the fuel injection control subsystem, the second single-chip microcomputer is electrically connected to the drive circuit, and the drive circuit is electrically connected to the fuel injector; the trigger module communicates with the second single-chip microcomputer through the data communication module, thereby transmitting the trigger instruction to the second single-chip microcomputer;

[0011] The first single-chip microcomputer and the second single-chip microcomputer communicate with the computer via a data communication module;

[0012] The computer transmits the set PID parameters to the first single-chip microcomputer and transmits the set injection parameters to the second single-chip microcomputer;

[0013] The power amplifier controls the opening and closing of the proportional solenoid valve according to the signal from the first single chip microcomputer, thereby realizing the regulation of the oil volume in the high-pressure oil circuit;

[0014] The first single-chip microcomputer performs PID control according to the pressure measured by the pressure sensor and the pressure set by the computer, and the second single-chip microcomputer controls the fuel injector to spray fuel through the drive circuit according to the trigger instruction of the trigger module and the fuel injection parameters provided by the computer;

[0015] Among them, the first single-chip microcomputer controls the duty cycle and fuel supply information according to the current rail pressure value of the pressure sensor, the preset rail pressure value and the PID parameters transmitted by the computer; the injection parameters include injection timing, injection pulse width, number of injections, injection interval time, and waveform parameters.

[0016] Furthermore, the pressure measurement range of the pressure sensor is 0-200Mpa.

[0017] Furthermore, the data communication module is an SCI communication module.

[0018] Furthermore, the maximum power of the power amplifier is 20W. When the power amplifier provides a low potential of 0V, the proportional solenoid valve is in a non-conducting state; when the power amplifier provides a high potential of 5V, the proportional solenoid valve is opened.

[0019] Furthermore, the trigger module is controlled by an operator or a power system of the aircraft engine to generate a fuel injection signal.

[0020] Furthermore, the drive circuit includes a boost circuit and a current segmentation control circuit. The boost circuit is a 12V to 60V boost circuit, which can accelerate the rising speed of the drive current and shorten the opening time of the injector, thereby providing a high voltage for the valve core of the injector at the opening time; the current segmentation control circuit can provide a rising stage current in the injection triggering stage and a maintenance stage current to maintain the injection of the injector. The rising stage current is 20A, and the maintenance stage current is 15A.

[0021] Furthermore, the first single chip computer transmits the pressure value from the pressure sensor to the computer through the data communication module, and displays the pressure value on the display of the computer in real time.

[0022] Compared with the prior art, the beneficial effects brought by the technical solution of the utility model are:

[0023] The high-pressure common rail fuel injection system of the utility model has the functions of pressure collection, pressure regulation, data communication processing and fuel injection control; the electronic control system includes two subsystems, each of which has a single-chip microcomputer and is controlled by dual microprocessors running in parallel, and can respectively realize high-pressure common rail pressure maintenance and fuel injection control. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural schematic diagram of the electronic control system of the high-pressure common rail fuel injection of the utility model;

[0025] Figure 2 It is a schematic diagram of the injector voltage and current waveform.

[0026] In the figure:

[0027] 1: Proportional solenoid valve; 2: Power amplifier; 4: Data communication module;

[0028] 5: low pressure oil circuit; 6: oil pump; 7: high pressure oil circuit; 8: common rail pressure sensor;

[0029] 9: fuel injector; 10: drive circuit; 11: boost circuit;

[0030] 12: trigger module 13: computer 31: first single chip microcomputer; 32: second single chip microcomputer. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical scheme, beneficial effects and significant progress of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model is clearly and completely described below in combination with the drawings provided in the examples of the utility model. Obviously, all the described embodiments are only partial embodiments of the utility model, rather than all embodiments; based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0032] In the description of this application, unless otherwise clearly specified and limited, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance; the term "plurality" refers to two or more; unless otherwise specified or explained, the terms "connected", "fixed", etc. should be understood in a broad sense, for example, "connected" can be a fixed connection, a detachable connection, an integral connection, or an electrical connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0033] like Figure 1 As shown, an electronic control system for high-pressure common rail fuel injection of an aircraft engine includes a PID rail pressure control subsystem, an injection control subsystem and a computer 13, wherein the PID rail pressure control subsystem includes a low-pressure oil circuit 5, an oil pump 6, a high-pressure oil circuit 7, a common rail pressure sensor 8, a proportional solenoid valve 1, a power amplifier 2 and a first single-chip microcomputer 31; the injection control subsystem includes an injector 9, a drive circuit 10, a boost circuit 11, a trigger module 12 and a second single-chip microcomputer 32.

[0034] Among them, in the PID rail pressure control subsystem, the low-pressure oil circuit 5, the proportional solenoid valve 1, the oil pump 6, and the high-pressure oil circuit 7 are connected in sequence, that is, the outlet of an oil tank is connected to the inlet of the low-pressure oil circuit 5, the outlet of the low-pressure oil circuit 5 is connected to the proportional solenoid valve 1, the other end of the proportional solenoid valve 1 is connected to the oil pump 6, and then pumped into the high-pressure oil circuit 7; the outlet of the high-pressure oil circuit 7 is connected to the injector 9 through a pipeline. The common rail pressure sensor 8 located on the high-pressure oil circuit 7 detects the current oil pressure and transmits it to the first single-chip microcomputer 31. The first single-chip microcomputer 31 is used to output PWM waves to the power amplifier 2 according to the data transmitted by the common rail pressure sensor 8 and the target rail pressure value from the computer 13, and then control the proportional solenoid valve 1 to adjust the amount of oil pressed into the high-pressure oil circuit 7 in real time, thereby controlling the pressure in the high-pressure oil circuit 7 and realizing the dynamic stability of the rail pressure. The pressure sensor 8 and the power amplifier 2 are electrically connected to the first single-chip microcomputer 31 respectively. The first single-chip microcomputer 31 receives the current pressure value of the pressure sensor 8, transmits the pressure value to the computer 13 through the data communication module 4, and displays it on the computer display in real time, and receives the preset rail pressure value transmitted from the computer 13 and the PID parameters transmitted by the computer through the data communication module 4.

[0035] Among them, in the fuel injection control subsystem, the trigger module 12 is electrically connected to the data communication module 4, and transmits the trigger instruction to the second single-chip microcomputer 32 through the data communication module 4. The second single-chip microcomputer 32 receives the trigger instruction through the data communication module 4, and receives the fuel injection parameters transmitted from the computer 13 through the data communication module 4 and sends them to the drive circuit 10. The drive circuit uses the 60V voltage of the boost circuit to output the rising stage current, thereby controlling the injection of the injector 9. The fuel injection parameters include the injection time, the injection pulse width, the number of injections, the injection interval time, and the waveform parameters.

[0036] The computer 13 transmits the set PID parameters to the first single-chip microcomputer 31, and transmits the set injection parameters to the second single-chip microcomputer 32. The first single-chip microcomputer 31 performs PID control according to the pressure measured by the pressure sensor and the pressure set by the computer. The second single-chip microcomputer starts to inject fuel after the trigger module 12 issues a trigger instruction based on the injection parameters proposed by the computer.

[0037] The first single chip microcomputer controls the duty cycle and fuel supply information according to the current rail pressure value of the pressure sensor, the preset rail pressure value and the PID parameters transmitted by the computer; the injection parameters include injection time, injection pulse width, injection number, injection interval time and waveform parameters.

[0038] The oil pump 6 is a CP1H3 type 0445010159 series oil pump from Bosch, and the oil pressure adjustment range is 0-145MPa; the oil pump is equipped with a three-phase asynchronous motor, the motor power is 3.0kW, and the speed is 1400r / min. The common rail pressure sensor 8 is a Bosch 0281006364 type pressure sensor, which is installed at one end of the common rail, and the signal collected by the common rail pressure sensor is processed by the first single chip microcomputer. The pressure measurement range of the common rail pressure sensor 8 is 0-200MPa.

[0039] The first and second single-chip microcomputers are both Freescale series single-chip microcomputers MC9S12XEP100, which are 16-bit single-chip microcomputers with 112-pin packages and coprocessors XGATE. The bus frequency can reach up to 120MHz, with 8-way digital-to-analog conversion and PWM independent output channels. At the same time, there are 8-way ECT modules and 8-way SCI modules. Based on the position PID control rail pressure, the first single-chip microcomputer 31 filters the current rail pressure value, receives the target rail pressure value and the PID proportional coefficient, differential coefficient, integral coefficient, control frequency and other parameters from the computer 17, and then performs PID processing on the filtered current rail pressure value and the target rail pressure value, and adds the integral separation term, and then outputs a PWM wave with a fixed frequency and a variable duty cycle to the power amplifier 2, thereby controlling the opening of the proportional solenoid valve 1 to achieve dynamic stability of the rail pressure. At the same time, the single-chip microcomputer returns the pressure read by the pressure sensor 8 to the computer 13 through the data communication module 4 and displays it on its display.

[0040] The power amplifier 2 is a PWM wave power amplifier, which is used to control the opening of the proportional solenoid valve 1, thereby controlling the amount of fuel from the low-pressure oil circuit 5 to the high-pressure oil circuit 7 to maintain the balance of the rail pressure. The power amplifier 2 is powered by a 5V regulated power supply with a maximum power of 20W, which can ensure the normal operation of the proportional solenoid valve.

[0041] The proportional solenoid valve 1 uses the Bosch 0928400728 proportional solenoid valve matched with the oil pump 6. When the power amplifier 2 provides a low potential of 0V, the proportional solenoid valve 1 is in a non-conducting state; when the power amplifier 2 provides a high potential of 5V, the proportional solenoid valve 1 is turned on. By controlling the opening frequency of the proportional solenoid valve 1, the amount of fuel pressed into the high-pressure oil circuit from the low-pressure oil circuit is controlled. The rail pressure is maintained basically unchanged by achieving a dynamic balance between the oil inlet and the oil return.

[0042] The data communication module 4 is an SCI communication module, which is a communication module provided by the first and second single-chip microcomputers, and communicates with the computer 13 via a serial port.

[0043] The trigger module 12 is controlled by an operator or the power system of the aircraft engine to generate an injection signal. A ZK-PP1K pulse generator is selected, which can generate pulse square waves in PWM mode and PULSE mode. The PWM mode realizes continuous pulses according to the frequency and duty cycle, while the PULSE pulse mode can realize different pulse width times, different delays, and different numbers of pulses. The trigger module 12 supports a frequency range of 1Hz-150kHz.

[0044] The driving circuit 10 includes a boost circuit and a current segmentation control circuit; the boost circuit 11 is a 12V to 60V boost circuit, which can speed up the rising speed of the driving current and shorten the opening time of the injector, thereby providing a high voltage for the valve core of the injector 9 at the opening time; the current segmentation control circuit can provide two driving currents, namely, the rising stage current of the injection triggering stage and the maintaining stage current of the injector to maintain the injection of the injector. The rising stage current is in the process of opening the valve core of the injector 9, using high voltage power supply to increase the leading edge rising rate of the current to speed up the opening speed of the valve core; the maintaining stage current is in the process of opening the valve core of the injector 9, using low voltage power supply to form a small current to maintain the valve core in the fully open position, and the injector voltage and current waveforms finally realized are as follows: Figure 2 shown.

[0045] The working principle of the electronic control system of the aircraft engine high pressure common rail injection is as follows:

[0046] The fuel from the oil tank flows into the low-pressure oil circuit 5 through the pipeline, and then passes through the proportional solenoid valve 1 and the oil pump 6 to increase the oil pressure, and then enters the high-pressure oil circuit 7; the pressure sensor 8 located in the high-pressure oil circuit 7 detects the current oil pressure and transmits it to the first single-chip microcomputer 31, and then uploads the PID information in the PID rail pressure control subsystem to the computer 13;

[0047] When the trigger module 12 generates an injection signal, the injection signal is transmitted to the second single chip computer 3;

[0048] The first single-chip microcomputer controls the duty cycle and the oil supply according to the pressure measured by the pressure sensor, the rail pressure value preset by the computer, and the PID parameters transmitted by the computer, thereby performing PID control, maintaining the oil pressure in the high-pressure oil circuit 7, and achieving dynamic stability of the rail pressure; at the same time, the first single-chip microcomputer transmits the pressure value from the pressure sensor 8 to the computer 13 through the data communication module 4, and displays the pressure value on the computer display; the second single-chip microcomputer 32 performs fuel injection control according to the trigger instruction and the fuel injection parameters provided by the computer;

[0049] The power amplifier 2 controls the opening and closing of the proportional solenoid valve 1 according to the signal from the first single chip microcomputer, and the fuel passes through the low-pressure oil circuit 5, the proportional solenoid valve 1, the oil pump 6, and the high-pressure oil circuit 7 in sequence, and then the high-pressure fuel flows into the injector;

[0050] According to the instruction of the computer 13 , the boost circuit 11 is turned on, and the second single chip microcomputer 32 controls the operation of the injector through the driving circuit 10 .

[0051] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode includes only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in the embodiments may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. An electronic control system for high pressure common rail fuel injection of an aircraft engine, characterized in that: It includes a PID rail pressure control subsystem, a fuel injection control subsystem and a computer (13); The PID rail pressure control subsystem comprises a low-pressure oil circuit (5), an oil pump (6), a high-pressure oil circuit (7), a proportional solenoid valve (1), a power amplifier (2) and a first single-chip computer (31); the fuel injection control subsystem comprises a fuel injector (9), a drive circuit (10), a trigger module (12) and a second single-chip computer (32); In the PID rail pressure control subsystem, a low-pressure oil circuit (5), a proportional solenoid valve (1), an oil pump (6), and a high-pressure oil circuit (7) are connected in sequence, and the end of the high-pressure oil circuit (7) is connected to an injector (9); the proportional solenoid valve (1) is also electrically connected to a power amplifier (2); A pressure sensor (8) is arranged on the high-pressure oil circuit (7) and is used to transmit the current rail pressure value to the first single-chip computer (31) in real time; the first single-chip computer (31) is electrically connected to the pressure sensor (8) and the power amplifier (2); In the fuel injection control subsystem, the second single-chip microcomputer (32) is electrically connected to the drive circuit (10), and the drive circuit (10) is electrically connected to the fuel injector (9); the trigger module (12) communicates with the second single-chip microcomputer (32) via the data communication module (4); The first single-chip microcomputer and the second single-chip microcomputer communicate with a computer (13) via a data communication module (4); The computer (13) transmits the set PID parameters to the first single-chip computer (31), and transmits the set fuel injection parameters to the second single-chip computer (32); the first single-chip computer (31) transmits the pressure value from the pressure sensor (8) to the computer (13), and displays the pressure value on a display of the computer; The power amplifier (2) controls the opening and closing of the proportional solenoid valve (1) according to the signal from the first single chip computer, thereby realizing the regulation of the oil volume in the high-pressure oil circuit (7); The second single chip computer (32) controls the fuel injector to spray fuel through the driving circuit according to the trigger instruction of the trigger module and the fuel spray parameters provided by the computer; The injection parameters include injection time, injection pulse width, injection times, injection interval time, and waveform parameters.

2. The electronic control system for high pressure common rail fuel injection of an aircraft engine according to claim 1, characterized in that: The data communication module (4) is an SCI communication module.

3. The electronic control system for high pressure common rail fuel injection of an aircraft engine according to claim 1, characterized in that: The power amplifier (2) has a maximum power of 20W. When the power amplifier (2) provides a low potential of 0V, the proportional solenoid valve (1) is in a non-conducting state; when the power amplifier (2) provides a high potential of 5V, the proportional solenoid valve (1) is opened.

4. The electronic control system for high pressure common rail fuel injection of an aircraft engine according to claim 1, characterized in that: The trigger module (12) is controlled by an operator or a power system of the aircraft engine to generate a fuel injection signal.

5. The electronic control system for high pressure common rail fuel injection of an aircraft engine according to claim 1, characterized in that: The driving circuit (10) comprises a boost circuit (11) and a current segmentation control circuit, wherein the boost circuit (11) is a 12V to 60V boost circuit; the current segmentation control circuit can provide a rising phase current in the injection triggering phase and a maintaining phase current for maintaining the injection of the injector, wherein the rising phase current is 20A and the maintaining phase current is 15A.

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