Control method and control system for preventing surge of supercharger and electronic control unit

Abstract

The invention provides a control method and system for preventing surge of a supercharger and an electronic control unit, and relates to the technical field of electromechanical control. According to the control method for preventing surge of the supercharger, the supercharger comprises a gas compressor and a turbine, and the control method comprises the steps that operation parameters of the supercharger are obtained; according to the operation parameters, whether the operation point of the engine is located in a surge margin area or not is judged; wherein the operation point is the position, on the performance MAP curve graph, of an engine working condition point determined according to the air mass flow at an air inlet of the air compressor and the pressure ratio of the air compressor; and when the operation point is located in the surge margin area, the oil injection quantity of the engine and / or the opening degree of a guide vane in the supercharger are / is adjusted, and the operation point is controlled to be located outside the surge margin area. According to the control method and system for preventing surge of the supercharger and the electronic control unit, the surge phenomenon of the supercharger is avoided, and the operation stability of the supercharger is improved.

Description

Technical Field

[0001] The present invention relates to the field of electromechanical control technology, and in particular to a control method and control system and an electronic control unit for preventing surge of a supercharger. Background Art

[0002] Surge is a phenomenon in which the turbocharger airflow fluctuates violently and is accompanied by huge noise when the turbocharger flow rate decreases to a certain level.

[0003] Surge phenomenon can cause the turbocharger impeller to vibrate due to loss of control, often accompanied by obvious whistling or hissing sounds. Turbocharger surge can have a certain impact on the use and life of the turbocharger. In addition, surge can also cause mismatch between the turbocharger and the diesel engine, affecting the normal operation of the diesel engine and may even cause greater mechanical damage. Summary of the invention

[0004] The embodiments of the present invention provide a control method and a control system for preventing surge of a supercharger, and an electronic control unit, so as to avoid surge of the supercharger, improve the operation stability of the supercharger, and extend the service life of the supercharger.

[0005] In a first aspect, an embodiment of the present invention provides a control method for preventing surge of a supercharger, wherein the supercharger includes a compressor and a turbine, and the control method includes:

[0006] Obtaining the operating parameters of the supercharger;

[0007] According to the operating parameters, determining whether the operating point of the engine is within the surge margin region; wherein the operating point is the position of the engine operating point on the performance MAP curve diagram determined according to the air mass flow at the compressor inlet and the compressor pressure ratio;

[0008] When the operating point is within the surge margin region, the fuel injection amount of the engine and / or the opening of the guide vanes inside the supercharger are adjusted to control the operating point to be outside the surge margin region.

[0009] Optionally, before obtaining the operating parameters of the supercharger, the method further includes:

[0010] Obtain the performance MAP curve of the compressor;

[0011] Obtain the surge margin area based on the performance MAP curve.

[0012] Optionally, the surge margin area is obtained according to the performance MAP curve diagram, including:

[0013] Obtain the surge line based on the performance MAP curve chart;

[0014] A 10% area close to the surge line is set as a surge margin area.

[0015] Optionally, the operating parameters include at least one of the following parameters:

[0016] The speed of the compressor, the temperature and pressure at the compressor inlet and outlet, and the temperature and pressure at the turbine inlet and outlet.

[0017] Optionally, the step of adjusting the engine fuel injection amount includes:

[0018] Increase the amount of fuel injected into the engine;

[0019] The steps for adjusting the opening of the guide vanes inside the supercharger include:

[0020] Increase the opening of the guide vanes inside the supercharger.

[0021] Optionally, after determining whether the operating point of the engine is within the surge margin region according to the operating parameters, the method further includes:

[0022] When the operating point is within the surge margin region, the anti-surge valve is controlled to operate and the gas is returned to the inlet of the compressor.

[0023] In a second aspect, an embodiment of the present invention provides an electronic control unit, the electronic control unit comprising:

[0024] one or more controllers;

[0025] A storage device for storing one or more programs;

[0026] When one or more programs are executed by one or more controllers, the one or more controllers implement the control method provided by any embodiment of the present invention.

[0027] In a third aspect, an embodiment of the present invention provides a control system for preventing surge of a supercharger, wherein the supercharger includes a compressor and a turbine, and includes an injection quantity control unit and / or an electronically controlled valve, and an electronic control unit provided in the second aspect;

[0028] The fuel injection quantity control unit is used to adjust the fuel injection quantity of the engine;

[0029] The electronically controlled valve is used to adjust the opening of the guide vanes inside the supercharger.

[0030] Optionally, the control system further includes:

[0031] A speed sensor, used to obtain the speed of the compressor;

[0032] A first temperature and pressure sensor is disposed at the inlet of the compressor and is used to obtain the temperature and pressure of the inlet of the compressor;

[0033] A second temperature and pressure sensor is disposed at the outlet of the compressor and is used to obtain the temperature and pressure of the outlet of the compressor;

[0034] A third temperature and pressure sensor is disposed at the inlet of the turbine and is used to obtain the temperature and pressure at the inlet of the turbine;

[0035] The fourth temperature and pressure sensor is disposed at the outlet of the turbine and is used to obtain the temperature and pressure of the outlet of the turbine.

[0036] Optionally, the control system further includes a MAF flow meter, which is disposed at the front end of the compressor and is used to measure the air flow entering the compressor.

[0037] A control method for preventing a supercharger from surging is provided in an embodiment of the present invention. The method calculates an operating point of an engine according to operating parameters of the supercharger. When the operating point is in a surge margin region, an electronic control unit changes the working state of the supercharger by adjusting the fuel injection amount of the engine and the opening of guide vanes inside the supercharger, so that the operating point leaves the surge margin region, thereby avoiding surging of the supercharger, improving the operating stability of the supercharger, and extending the service life of the supercharger. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 is a flow chart of a control method for preventing supercharger surge provided by an embodiment of the present invention;

[0039] Figure 2 It is the relationship diagram between the performance MAP curve and the 10% surge margin curve;

[0040] Figure 3 is a flow chart of another control method for preventing supercharger surge provided by an embodiment of the present invention;

[0041] Figure 4 It is a structural schematic diagram of a control system for preventing supercharger surge provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0042] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0043] When the flow rate and pressure ratio of the supercharger are within a certain range, the supercharger will surge. In order to avoid the surge of the supercharger, it is necessary to divide the surge margin.

[0044] An embodiment of the present invention provides a control method for preventing surge of a supercharger, wherein the supercharger includes a compressor and a turbine. Figure 1 is a flow chart of a control method for preventing surge of a supercharger provided by an embodiment of the present invention, with reference to Figure 1 , control methods include:

[0045] S101. Obtain operating parameters of a supercharger.

[0046] The electronic control unit detects the operating parameters of the supercharger through sensors.

[0047] S102. Determine whether the operating point of the engine is within the surge margin region based on the operating parameters; wherein the operating point is the position of the engine operating point on the performance MAP curve diagram determined based on the air mass flow at the compressor inlet and the compressor pressure ratio.

[0048] Specifically, the electronic control unit calculates the air mass flow at the compressor inlet and the compressor pressure ratio according to the operating parameters, thereby determining the operating point of the engine. Figure 2 This is the relationship between the performance MAP curve and the 10% surge margin curve. Figure 2 , Figure 2 The horizontal axis is the air mass flow rate at the compressor inlet of the supercharger, the vertical axis is the pressure ratio of the compressor, the black curve is the performance MAP curve, and the performance MAP curves 201, 202, 203 and 204 form a closed area. The red dotted line is the 10% surge margin curve. The closed area between the 10% surge margin curve and the performance MAP curve 204 is the surge margin area of ​​the supercharger. When the operating point of the engine is in this area, the supercharger is at risk of surge. The closed area formed by the 10% surge margin curve and the performance MAP curves 201, 202 and 203 is the normal working area of ​​the supercharger. When the operating point is in this normal working area, the supercharger will not experience surge.

[0049] S103: When the operating point is within the surge margin region, adjust the fuel injection amount of the engine and / or the opening of the guide vanes inside the supercharger to control the operating point to be outside the surge margin region.

[0050] Specifically, combined Figure 1 and Figure 2 As shown, when the operating point is within the surge margin region, the electronic control unit dynamically adjusts the engine fuel injection amount and / or the guide vane opening inside the supercharger to move the operating point outside the surge margin region. For example, the operating point can be moved to the right by increasing the fuel injection amount and the guide vane opening, so that the operating point leaves the surge margin region and enters the normal working region.

[0051] A control method for preventing a supercharger from surging is provided in an embodiment of the present invention. The method calculates an operating point of an engine according to operating parameters of the supercharger. When the operating point is in a surge margin region, an electronic control unit changes the working state of the supercharger by adjusting the fuel injection amount of the engine and the opening of guide vanes inside the supercharger, so that the operating point leaves the surge margin region, thereby avoiding surging of the supercharger, improving the operating stability of the supercharger, and extending the service life of the supercharger.

[0052] Figure 3 is a flow chart of another control method for preventing surge of a supercharger provided by an embodiment of the present invention, with reference to Figure 3 , control methods include:

[0053] S201. Obtain a performance MAP curve diagram of a compressor.

[0054] Specifically, the electronic control unit internally stores a supercharger performance MAP curve.

[0055] S202: Obtain a surge line according to a performance MAP curve diagram.

[0056] Specifically, in the performance MAP curve diagram, a curve formed by operating points where the supercharger may experience surge is a surge line.

[0057] S203 , setting a 10% area close to the surge line as a surge margin area.

[0058] Specifically, in order to avoid the surge phenomenon of the supercharger, the operating point needs to be far away from the surge line, so the 10% area close to the surge line is set as the surge margin area.

[0059] S204: Obtain operating parameters of the supercharger.

[0060] S205. Determine whether the operating point of the engine is within the surge margin region based on the operating parameters; wherein the operating point is the position of the engine operating point on the performance MAP curve diagram determined based on the air mass flow at the compressor inlet and the compressor pressure ratio.

[0061] S206. When the operating point is within the surge margin region, the anti-surge valve is controlled to operate so as to return the gas to the inlet of the compressor.

[0062] Specifically, the anti-surge valve is used to return gas to the inlet of the compressor, increase the flow of the supercharger, and make the operating point leave the surge margin area.

[0063] S207: When the operating point is within the surge margin region, increase the fuel injection amount of the engine and / or increase the opening of the guide vanes inside the supercharger to control the operating point to be outside the surge margin region.

[0064] Specifically, increasing the amount of fuel injected into the engine can provide more energy to the engine, while the exhaust gas discharged by the engine will also increase. The supercharger needs to use the inertial impact of the exhaust gas discharged by the engine to drive the turbine in the turbine chamber of the supercharger, and the turbine drives the coaxial impeller, which presses the air sent from the air filter pipe. Therefore, increasing the amount of fuel injected into the engine can increase the air mass flow at the compressor inlet of the supercharger, so that the operating point leaves the surge margin area. Similarly, increasing the opening of the guide vanes inside the supercharger can also increase the air mass flow at the compressor inlet of the supercharger, so that the operating point leaves the surge margin area.

[0065] It should be noted that the above steps S206 and S207 can be performed simultaneously, that is, while increasing the engine fuel injection amount and / or increasing the opening of the guide vanes inside the supercharger, the anti-surge valve is also controlled to operate to return the gas to the inlet of the compressor.

[0066] Optionally, the operating parameters include at least one of the following parameters: the speed of the compressor, the temperature and pressure of the compressor inlet and outlet, and the temperature and pressure of the turbine inlet and outlet. The air mass flow rate at the compressor inlet of the supercharger and the pressure ratio of the supercharger can be calculated based on the above operating parameters. The pressure ratio of the compressor is the pressure at the compressor outlet of the supercharger divided by the pressure at the compressor inlet of the supercharger.

[0067] Based on the same inventive concept, an embodiment of the present invention provides an electronic control unit, which includes: one or more controllers; a storage device for storing one or more programs; when the one or more programs are executed by one or more controllers, the one or more controllers implement the control method provided by any embodiment of the present invention.

[0068] The electronic control unit is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic control unit may also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the invention described and / or claimed herein.

[0069] The electronic control unit includes at least one processor, and a memory such as a read-only memory or a random access memory that is communicatively connected to the at least one processor, wherein the memory stores a computer program that can be executed by at least one processor, and the processor can perform various appropriate actions and processes according to the computer program stored in the read-only memory or the computer program loaded from the storage unit into the random access memory. In the random access memory, various programs and data required for the operation of the electronic control unit can also be stored. The processor, the read-only memory, and the random access memory are connected to each other through a bus. An input / output (I / O) interface is also connected to the bus.

[0070] Many components in the electronic control unit are connected to the I / O interface, including: input units, such as keyboards, mice, etc.; output units, such as various types of displays, speakers, etc.; storage units, such as disks, optical disks, etc.; and communication units, such as network cards, modems, wireless communication transceivers, etc. The communication unit allows the electronic control unit to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunication networks.

[0071] The processor can be a variety of general and / or special processing components with processing and computing capabilities. Some examples of processors include, but are not limited to, central processing units (CPUs), graphics processing units (GPUs), various dedicated artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, digital signal processors (DSPs), and any appropriate processors, controllers, microcontrollers, etc.

[0072] Based on the same inventive concept, an embodiment of the present invention provides a control system for preventing surge of a supercharger. Figure 4 Schematic diagram of a control system for preventing surge of a supercharger provided by an embodiment of the present invention, with reference to Figure 4 The supercharger includes a compressor 100 and a turbine 200, and the control system includes a fuel injection quantity control unit 300 and / or an electronic control valve 400, and an electronic control unit 500 provided in an embodiment of the present invention; the fuel injection quantity control unit 300 is used to adjust the fuel injection quantity of the engine 600; the electronic control valve 400 is used to adjust the opening of the guide vane inside the supercharger.

[0073] By adjusting the angle and position of the guide vane inside the supercharger, the cross-sectional area of ​​the supercharger air inlet can be changed, thereby controlling the speed of the turbine 200 and the boost pressure of the compressor 100. When the engine 600 is in a low speed and low exhaust volume working state, the guide vane will be closed or partially closed to reduce the cross-sectional area of ​​the exhaust inlet. In this way, the speed of the exhaust gas entering the turbine 200 will increase, thereby increasing the speed of the turbine 200, and then increasing the intake volume, which helps to improve the response speed and acceleration performance of the engine 600 at low speed. When the engine 600 rotates at high speed, the exhaust volume increases, the guide vane will gradually open, and the cross-sectional area of ​​the exhaust inlet will be increased, which can reduce the exhaust back pressure, the speed of the exhaust gas entering the turbine 200 will slow down, the speed of the turbine 200 will be reduced accordingly, and the intake volume will be maintained within a suitable range, which helps to prevent excessive boosting when the engine 600 rotates at high speed, maintain the stable operation of the engine 600, and achieve the best boosting effect.

[0074] Combination Figure 1 , Figure 2 and Figure 4 As shown, when the operating point is within the surge margin area, the electronic control unit 500 can adjust the engine injection amount through the injection amount control unit 300 and adjust the guide vane opening inside the supercharger through the electronic control valve 400 to move the operating point outside the surge margin area.

[0075] Optionally, refer to Figure 4 The control system further includes: a speed sensor 700 for obtaining the speed of the compressor; a first temperature and pressure sensor 801, arranged at the inlet of the compressor 100, for obtaining the temperature and pressure of the inlet of the compressor 100; a second temperature and pressure sensor 802, arranged at the outlet of the compressor 100, for obtaining the temperature and pressure of the outlet of the compressor 100; a third temperature and pressure sensor 803, arranged at the inlet of the turbine 200, for obtaining the temperature and pressure of the inlet of the turbine 200; a fourth temperature and pressure sensor 804, arranged at the outlet of the turbine 200, for obtaining the temperature and pressure of the outlet of the turbine 200. The electronic control unit 500 is respectively connected to the speed sensor 700, the first temperature and pressure sensor 801, the second temperature and pressure sensor 802, the third temperature and pressure sensor 803 and the fourth temperature and pressure sensor 804, to detect the operating parameters of the supercharger in real time, and to determine whether the operating point is in the surge margin area according to the operating parameters.

[0076] Optionally, refer to Figure 4The control system also includes a MAF flowmeter 900, which is arranged at the front end of the compressor 100 and is used to measure the air flow entering the compressor 100. The impeller presses the air sent by the air filter 901 pipeline. The intercooler 902 is connected between the second temperature and pressure sensor 802 and the anti-surge valve 903. The function of the intercooler 902 is to reduce the temperature of the high-temperature air after supercharging, so as to reduce the heat load of the engine, increase the intake volume, and thus increase the power of the engine. The anti-surge valve 903 is also connected to the electronic control unit 500, and the electronic control unit 500 controls the working state of the anti-surge valve 903. The throttle 904 is connected between the anti-surge valve 903 and the engine 600. The throttle 904 is a controllable valve that controls the air entering the engine. After the gas enters the intake pipe, it will mix with gasoline to become a combustible mixture, thereby burning to form work. The VGT control module 905 is connected between the electric control valve 400 and the turbine 200. By adjusting the angle and position of the guide vane inside the turbocharger, the cross-sectional area of ​​the exhaust inlet is changed, thereby controlling the speed of the turbine and the boost pressure of the compressor. When the engine is in a low speed and low exhaust volume operating condition, the guide vane will be closed or partially closed to reduce the cross-sectional area of ​​the exhaust inlet. In this way, the speed at which the exhaust gas enters the turbine will increase, thereby increasing the speed of the turbine, and then increasing the intake volume, which helps to improve the response speed and acceleration performance of the engine at low speed. When the engine rotates at high speed and the exhaust volume increases, the guide vane will gradually open to increase the cross-sectional area of ​​the exhaust inlet. In this way, the exhaust back pressure is reduced, the speed at which the exhaust gas enters the turbine will slow down, the speed of the turbine will decrease accordingly, and the intake volume will be maintained within a suitable range, which helps to prevent excessive boost at high speed, maintain the stable operation of the engine, and achieve the best boost effect. The output end of the turbine 200 is also connected to the after-treatment system 906, which is used to post-treat the exhaust gas of the engine.

[0077] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, combinations and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A control method for preventing surge of a supercharger, wherein the supercharger comprises a compressor and a turbine, characterized in that: The control method comprises: Obtaining operating parameters of the supercharger; According to the operating parameters, determining whether the operating point of the engine is within the surge margin region; wherein the operating point is the position of the engine operating point on the performance MAP curve diagram determined according to the air mass flow at the compressor inlet and the compressor pressure ratio; When the operating point is within the surge margin region, the fuel injection amount of the engine and / or the opening of the guide vanes inside the supercharger are adjusted to control the operating point to be outside the surge margin region.

2. The control method according to claim 1, characterized in that: Before obtaining the operating parameters of the supercharger, the method further includes: Obtain the performance MAP curve of the compressor; The surge margin region is acquired according to the performance MAP curve diagram.

3. The control method according to claim 2, characterized in that: Acquiring the surge margin region according to the performance MAP curve diagram includes: Acquire a surge line according to the performance MAP curve diagram; A 10% region close to the surge line is set as the surge margin region.

4. The control method according to claim 1, characterized in that: The operating parameters include at least one of the following parameters: The rotation speed of the compressor, the temperature and pressure at the inlet and outlet of the compressor, and the temperature and pressure at the inlet and outlet of the turbine.

5. The control method according to claim 1, characterized in that: The steps to adjust the engine fuel injection amount include: Increase the amount of fuel injected into the engine; The step of adjusting the opening of the guide vanes inside the supercharger comprises: The opening of the guide vanes inside the supercharger is increased.

6. The control method according to claim 1, characterized in that: After determining whether the operating point of the engine is within the surge margin region according to the operating parameters, the method further includes: When the operating point is within the surge margin region, the anti-surge valve is controlled to operate so as to return gas to the inlet of the compressor.

7. An electronic control unit, characterized in that: The electronic control unit comprises: one or more controllers; A storage device for storing one or more programs; When the one or more programs are executed by the one or more controllers, the one or more controllers implement the control method as described in any one of claims 1 to 6.

8. A control system for preventing surge of a supercharger, the supercharger comprising a compressor and a turbine, characterized in that: It includes a fuel injection quantity control unit and / or an electric control valve, and an electronic control unit as claimed in claim 7; The fuel injection quantity control unit is used to adjust the fuel injection quantity of the engine; The electric control valve is used to adjust the opening of the guide vanes inside the supercharger.

9. The control system according to claim 8, characterized in that: Also includes: A rotation speed sensor, used to obtain the rotation speed of the compressor; A first temperature and pressure sensor, disposed at the inlet of the compressor, for obtaining the temperature and pressure of the inlet of the compressor; a second temperature and pressure sensor, disposed at the outlet of the compressor, for obtaining the temperature and pressure of the outlet of the compressor; a third temperature and pressure sensor, disposed at the inlet of the turbine, for obtaining the temperature and pressure at the inlet of the turbine; The fourth temperature and pressure sensor is arranged at the outlet of the turbine and is used to obtain the temperature and pressure of the outlet of the turbine.

10. The control system according to claim 8, characterized in that: It also includes a MAF flowmeter, which is arranged at the front end of the compressor and is used to measure the air flow entering the compressor.

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