CN114592968B - Control method, device and system for eliminating surge of supercharger - Google Patents

Abstract

The invention discloses a control method, device and system for eliminating surge of a supercharger. The control method includes: obtaining the current engine working condition parameters, the current gear position of the gearbox and the current gas tank pressure, and determining the current engine working condition parameters based on the current engine working condition parameters. The torque margin of the engine in the current gearbox gear. When receiving the engine power output reduction command, if the torque margin is not greater than the preset torque margin, the gearbox gear at the current adjacent acquisition time is determined based on the gear sampling frequency position difference, and when the current tank pressure is not less than the pressure threshold, determine the corresponding active intervention strategy for the intake boundary of the supercharger based on the relationship between the transmission gear difference and 0, so that when it is determined that the supercharger is about to enter the instantaneous In the state surge working condition, the high-pressure pressure supply system is controlled in advance to input the high-pressure gas into the pipeline system before the pressure of the supercharger and the end time, so as to eliminate the surge of the supercharger and avoid the occurrence of Surge noise.

Description

A control method, device and system for eliminating supercharger surge

technical field

The invention relates to the field of electromechanical technology, and more specifically, relates to a control method, device and system for eliminating surge of a supercharger.

Background technique

The supercharger can pre-compress the air or combustible mixture entering the engine cylinder to increase the density of the air or combustible mixture entering the cylinder, thereby increasing the power and economy of the engine, and improving the emission performance of the engine. Due to the many advantages that superchargers can bring to the engine, the application of tubes in the engine is also becoming more and more widespread.

However, when the power output of the engine changes from the high power zone to the low power zone, the supercharger (especially the turbocharger) will have a surge problem, which will cause a surge noise in the supercharger, which will affect the performance of the vehicle where the engine is located. passenger comfort. And when the surge problem is serious, it will also affect the performance of the engine.

Therefore, how to provide a method for eliminating the surge of the supercharger has become a technical problem that those skilled in the art urgently need to solve.

Contents of the invention

In view of this, the present invention discloses a control method, device and system for eliminating the surge of a supercharger, so as to achieve the purpose of eliminating the surge of the supercharger and avoid the surge noise of the supercharger.

A control method for eliminating supercharger surge, applied to an engine control unit, the control method comprising:

Obtain the current engine operating condition parameters, current gearbox gear and current gas tank pressure;

determining a torque margin of the engine at the current transmission gear based on the current engine operating condition parameters;

When receiving an engine power output reduction command, judging whether the torque margin is not greater than a preset torque margin;

If so, determine the gearbox gear difference at the current adjacent acquisition time based on the gear sampling frequency;

When the current gas tank pressure is not less than the pressure threshold, determine the corresponding supercharger intake boundary active intervention strategy based on the magnitude relationship between the gearbox gear difference and 0;

Wherein, the supercharger intake boundary active intervention strategy is used to control the high-pressure supply system in advance to input high-pressure gas into the pre-pressure pipeline of the supercharger compressor when it is determined that the supercharger is about to enter the transient surge condition The start time and end time of the system.

Optionally, the current engine operating condition parameters include: current engine speed, current speed torque and current speed full load torque;

The torque margin is the difference between the full load torque at the current speed and the torque at the current speed.

Optionally, the preset torque margin is determined based on the full load torque at the current speed and a surge torque coefficient, wherein the surge torque coefficient has different values at different transmission gears and different engine speeds.

Optionally, when the current gas tank pressure is not less than the pressure threshold, determining the corresponding supercharger intake boundary active intervention strategy based on the magnitude relationship between the transmission gear difference and 0 includes:

When the current gas tank pressure is not less than the pressure threshold, judging whether the gearbox gear difference is not equal to 0;

If yes, then control the high-pressure supply system to start working, and the high-pressure supply system will input high-pressure gas into the pre-pressure piping system of the supercharger compressor to increase the pressure of the supercharger compressor. Gas pressure in the front pipeline system;

Determine the engine speed difference at the current adjacent acquisition time based on the speed sampling frequency;

Judging whether the engine speed difference is greater than a preset speed difference, or the current gas tank pressure drops below the pressure threshold, or the opening time of the high-pressure pressure supply system reaches the upper limit of the opening time;

If yes, then control the high pressure supply system to stop working.

Optionally, also include:

When the gear difference of the gearbox is equal to 0, the high pressure supply system is controlled to start working, and the high pressure gas is input from the high pressure supply system to the pre-pressure pipeline system of the supercharger compressor to increase Increase the gas pressure in the pipeline system before the pressure of the supercharger compressor;

judging whether the current gas tank pressure drops below the pressure threshold, and the opening time of the high-pressure pressure supply system reaches the upper limit of the opening time;

If yes, then control the high pressure supply system to stop working.

Optionally, the high-pressure pressure supply system includes: an electromagnetic control valve, a high-pressure gas storage tank and an air compressor;

The control end of the air compressor is connected to the engine, the output end of the air compressor is connected to the high-pressure air storage tank, and the high-pressure air storage tank is connected to the high-pressure air storage tank through the electromagnetic control valve. On the connection path with the pre-pressure pipeline system of the supercharger compressor;

The control terminal of the electromagnetic control valve is connected with the engine control unit, and is used for turning on and off according to the on and off signals output by the engine control unit.

Optionally, when the current gas tank pressure is less than the pressure threshold, return to determine the transmission gear difference again.

A control device for eliminating supercharger surge is applied to an engine control unit, and the control device includes:

The acquisition unit is used to acquire the current engine operating condition parameters, the current transmission gear and the current gas tank pressure;

a torque margin determining unit, configured to determine the torque margin of the engine at the current transmission gear position based on the current engine operating condition parameters;

A judging unit, configured to judge whether the torque margin is not greater than a preset torque margin when receiving an engine power output reduction command;

A gear difference determination unit, configured to determine the gear difference of the gearbox at the current adjacent acquisition time based on the gear sampling frequency if the judging unit judges yes;

An intervention strategy determination unit, configured to determine a corresponding supercharger intake boundary active intervention strategy based on the magnitude relationship between the gearbox gear difference and 0 when the current gas tank pressure is not less than a pressure threshold;

Wherein, the supercharger intake boundary active intervention strategy is used to control the high-pressure supply system in advance to input high-pressure gas into the pre-pressure pipeline of the supercharger compressor when it is determined that the supercharger is about to enter the transient surge condition The start time and end time of the system.

Optionally, the intervention strategy determination unit includes:

A first judging subunit, configured to judge whether the gearbox gear difference is not equal to 0 when the current gas tank pressure is not less than the pressure threshold;

The first control subunit is used to control the high-pressure supply system to start working when the first determination subunit determines yes, and the high-pressure supply system inputs high-pressure gas to the supercharger The pipeline system before the pressure of the compressor is used to increase the gas pressure in the pipeline system before the pressure of the supercharger compressor;

The speed difference determination subunit is used to determine the engine speed difference at the current adjacent acquisition time based on the speed sampling frequency;

The second judging subunit is used to judge whether the engine speed difference is greater than the preset speed difference, or the current gas tank pressure drops below the pressure threshold, or the opening time of the high pressure supply system reaches open time limit;

The second control subunit is configured to control the high pressure supply system to stop working if the second judgment subunit judges yes.

Optionally, also include:

The third control subunit is used to control the high-pressure supply system to start working when the transmission gear difference is equal to 0, and the high-pressure supply system inputs high-pressure gas to the supercharger compressor A pre-pressure pipeline system to increase the gas pressure in the pre-pressure pipeline system of the supercharger compressor;

A third judging subunit, configured to judge whether the current gas tank pressure drops below the pressure threshold, and the opening time of the high-pressure pressure supply system reaches the upper limit of the opening time;

The fourth control subunit is configured to control the high pressure supply system to stop working if the third judging subunit judges yes.

A control system for eliminating turbocharger surge, including: engine, turbocharger front exhaust pipeline system, turbocharger turbine, turbocharger rear exhaust pipeline system, turbocharger compressor , the pipeline system before the pressure of the turbocharger compressor, the electromagnetic control valve, the high-pressure gas storage tank, the air compression, the pipeline system after the pressure of the turbocharger compressor and the engine control unit, wherein the engine control unit includes the above-mentioned said control device;

The pipeline system before the pressure of the turbocharger compressor is communicated with the pipeline system after the pressure of the turbocharger compressor through the compressor of the turbocharger, and the pipeline system after the pressure of the turbocharger compressor is The system is connected with the inlet of the engine, and the outlet of the engine is connected with the exhaust pipeline system before the turbocharger, and the exhaust pipeline system is connected with the turbocharger turbine through the turbocharger turbine. The exhaust pipeline system after the turbocharger is connected;

The control end of the air compressor is connected to the engine, the output end of the air compressor is connected to the high-pressure air storage tank, and the high-pressure air storage tank is connected to the high-pressure air storage tank through the electromagnetic control valve. On the connection path with the pre-pressure pipeline system of the supercharger compressor;

The control end of the electromagnetic control valve is connected to the engine control unit, and is used to conduct on and off according to the on and off signals output by the engine control unit;

The electromagnetic control valve, the high-pressure air tank and the air compressor constitute a high-pressure supply system.

It can be seen from the above technical solutions that the present invention discloses a control method, device and system for eliminating supercharger surge. The control method includes: obtaining the current engine operating condition parameters, the current gear position of the gearbox and the current gas tank pressure, Determine the torque margin of the engine at the current gearbox gear based on the current engine working condition parameters. When receiving the engine power output reduction command, if the torque margin is not greater than the preset torque margin, determine the current phase based on the gear sampling frequency. The gearbox gear difference at the adjacent collection time, and when the current tank pressure is not less than the pressure threshold, based on the relationship between the gearbox gear difference and 0, determine the corresponding active intervention strategy for the intake boundary of the supercharger, so as to When it is determined that the supercharger is about to enter the transient surge condition, the high-pressure pressure supply system is controlled in advance to input the high-pressure gas into the pre-compressor pipeline system of the supercharger. The purpose is to avoid the surge noise of the supercharger.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only It is an embodiment of the present invention. For those skilled in the art, other drawings can also be obtained according to the disclosed drawings without creative work.

FIG. 1 is a schematic composition diagram of a control system for eliminating surge of a supercharger disclosed in an embodiment of the present invention;

Fig. 2 is a flowchart of a control method for eliminating supercharger surge disclosed by an embodiment of the present invention;

Fig. 3 is a flow chart of a method for determining the corresponding active intervention strategy for the intake boundary of a supercharger based on the relationship between the difference between the gear position of the gearbox and 0 disclosed by the embodiment of the present invention;

Fig. 4 is a structural schematic diagram of a control device for eliminating surge of a supercharger disclosed in an embodiment of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The embodiment of the present invention discloses a control method, device and system for eliminating surge of a turbocharger. The control method includes: obtaining the current engine operating condition parameters, the current transmission gear position and the current gas tank pressure, and based on the current engine operating condition The parameter determines the torque margin of the engine in the current gearbox gear. When the engine power output reduction command is received, if the torque margin is not greater than the preset torque margin, the gear shift at the current adjacent acquisition time is determined based on the gear sampling frequency Gearbox gear difference, and when the current gas tank pressure is not less than the pressure threshold, determine the corresponding active intervention strategy for the supercharger intake boundary based on the relationship between the gearbox gear difference and 0, so as to determine that the supercharger is about to When entering the transient surge condition, the high-pressure supply system is controlled in advance to input the high-pressure gas into the pipeline system before the pressure of the supercharger and the end time, so as to eliminate the surge of the supercharger and avoid supercharging Surge noise occurs.

Referring to Fig. 1, a schematic diagram of the composition of a control system for eliminating supercharger surge disclosed in an embodiment of the present invention, the control system includes: an engine 1, a supercharger pre-turbo exhaust pipeline system 2, and a turbocharger turbine 3 , turbocharger exhaust pipeline system 4, turbocharger compressor 5, turbocharger compressor pre-pressure pipeline system 6, electromagnetic control valve 7, high-pressure gas storage tank 8, air compression 9, turbine The pipeline system 10 after the pressure of the supercharger compressor and the engine control unit (not shown in FIG. 1 ).

Wherein, the pipeline system 6 before the turbocharger compressor pressure is communicated with the pipeline system 10 after the turbocharger compressor pressure through the turbocharger compressor 5, and the pipeline system 10 after the turbocharger compressor pressure is connected with The inlet of the engine 1 is connected, and the outlet of the engine 1 is connected with the exhaust pipeline system 2 before the turbocharger. The pipeline system 4 communicates.

The control end of the air compressor 9 is connected to the engine 1, the output end of the air compressor 9 is connected to the high-pressure gas storage tank 8, and the high-pressure gas storage tank 8 is connected between the high-pressure gas storage tank 8 and the supercharger compressor through the electromagnetic control valve 7. On the connecting path of the front pipeline system 6.

The control terminal 7 of the electromagnetic control valve is connected with the engine control unit (not shown in FIG. 1 ), and is used to conduct on and off according to the on and off signals output by the engine control unit.

It should be noted that in this embodiment, the electromagnetic control valve 7, the high-pressure gas storage tank 8 and the air compressor 9 constitute a high-pressure supply system, the full name of which can be: Pressure supply system, abbreviated as PSS.

It should also be noted that the supercharger involved in the present invention may specifically be a turbocharger.

Referring to FIG. 2 , a flow chart of a control method for eliminating supercharger surge disclosed in an embodiment of the present invention, the control method is applied to the engine control unit in the embodiment shown in FIG. 1 , and the control method includes:

Step S101, obtaining the current engine operating condition parameters, the current gear position of the gearbox and the current pressure of the gas tank;

Wherein, the current engine operating condition parameters may include: current engine speed n ₁ , current speed torque T ₁ and current speed full load torque T _1full .

The current gearbox gear is represented by G, and the current gas tank pressure is represented by P.

Step S102, determining the torque margin of the engine at the current transmission gear based on the current engine operating condition parameters;

Among them, the torque margin △T is the difference between the current speed full load torque T _1full and the current speed torque T ₁ , the expression is as follows:

ΔT = T _1full - T ₁ .

Step S103. When the engine power output reduction command is received, it is judged whether the torque margin is not greater than the preset torque margin, and if yes, step S104 is executed;

Wherein, the value of the preset torque margin is determined according to actual needs, which is not limited in the present invention.

In this embodiment, when the engine power output reduction command is received, due to inertia, there is still high-energy exhaust gas in the exhaust pipe system 2 before the turbocharger turbocharger, and the turbocharger turbine 3 is still driven by the exhaust gas. Input power to the turbocharger compressor 5. With the reduction of the fuel supply of the engine 1, the demand for fresh air of the engine 1 decreases, and the accumulation in the pipeline system 6 before the turbocharger compressor pressure cannot be achieved in a short time. As the turbocharger speed decreases, the amount of gas in the piping system 6 before the turbocharger compressor decreases, resulting in the high pressure ratio and low flow rate of the turbocharger compressor. trend of the situation.

In practical applications, there are many ways to determine that the engine power output reduction command is received, for example, a 0% throttle opening requirement is received.

Wherein, the preset torque margin ΔT _threshold is determined based on the current rotational speed full-load torque T _1full and the surge torque coefficient K1, and the expression of the preset torque margin ΔT _threshold is as follows:

ΔT _threshold = K1*T _1full .

It should be noted that the numerical value of the surge torque coefficient K1 can reflect the severity of the surge, and the surge torque coefficient K1 is calculated in the actual application scenario of the vehicle. The value of the surge torque coefficient K1 is different under different transmission gears and different engine speeds. In the electronic control calibration program, the value of the surge torque coefficient K1 is a curve CURVE.

Examples of surge torque coefficients under different transmission gears can be seen in Table 1:

Table 1

Wherein, in Table 1, 0≤k _1i ≤1.

Refer to Table 1, for example, when the transmission gear G is the fifth gear, the engine speed n ₁ is 1800r/min, the current speed torque T ₁ at this speed is 1000N.m, and the full load torque T _1full at the engine speed n ₁ is 1800N. m, the calculated torque margin △T at 1800r/min is 800N.m.

The preset torque margin is 0.5×1800N.m=900N.m.

In this embodiment, ΔT=800N.m<900N.m, therefore, continue to execute step S104.

It should be noted that, when the torque margin is greater than the preset torque margin, return to step S101 to obtain the latest engine operating condition parameters, transmission gear and gas tank pressure again.

Step S104, determining the gear difference value of the gearbox at the current adjacent acquisition time based on the gear sampling frequency;

According to the gear sampling frequency f1, two groups of gearbox gears are continuously collected, namely: G _i and G _i+1 , then the gear difference ΔG=G _i -G _i+1 .

Step S105, when the current gas tank pressure is not less than the pressure threshold, determine the corresponding active intervention strategy for the intake boundary of the supercharger based on the magnitude relationship between the transmission gear difference and 0;

Wherein, the supercharger intake boundary active intervention strategy is used to control the high-pressure supply system in advance to input high-pressure gas into the pre-pressure pipeline of the supercharger compressor when it is determined that the supercharger is about to enter the transient surge condition The start time and end time of the system.

The value of the pressure threshold is determined according to needs, and the present invention does not make a limitation here.

As shown in Figure 1, the medium and high-pressure pressure supply system of the present invention includes: an electromagnetic control valve 7, a high-pressure gas storage tank 8, and an air compressor 9. The specific implementation process of the active intervention strategy for the supercharger intake boundary is as follows: When entering the transient surge working condition, the high-pressure gas in the high-pressure gas storage tank 8 is compressed by the air compressor 9 in advance, and the high-pressure gas in the high-pressure gas storage tank 8 flows into the supercharger compressor by controlling the conduction of the electromagnetic control valve 7 In the pre-pressure pipeline system 2, and by controlling the solenoid control valve 7 to shut off to block the high-pressure gas in the high-pressure gas storage tank 8 from flowing into the supercharger compressor pre-pressure pipeline system 2, it can adjust the turbocharger The role of the compressor 5 away from the surge area, thereby achieving the purpose of eliminating the surge of the supercharger and avoiding the surge noise of the supercharger.

In summary, the present invention discloses a control method for eliminating turbocharger surge, which obtains the current engine operating condition parameters, the current transmission gear position and the current gas tank pressure, and determines the current engine operating condition parameters based on the current engine operating condition parameters. For the torque margin under the gear position, when the engine power output reduction command is received, if the torque margin is not greater than the preset torque margin, the gearbox gear difference at the current adjacent acquisition time is determined based on the gear position sampling frequency, and When the current tank pressure is not less than the pressure threshold, determine the corresponding supercharger intake boundary active intervention strategy based on the relationship between the gearbox gear difference and 0, so that when it is determined that the supercharger is about to enter the transient surge condition When the high-pressure pressure supply system is used to control the start time and end time of the high-pressure gas supply system inputting the high-pressure gas into the pipeline system before the pressure of the supercharger compressor, the purpose of eliminating the surge of the supercharger is achieved and the surge noise of the supercharger is avoided.

In order to further optimize the above embodiment, see FIG. 3 , which is a flow chart of a method for determining the corresponding active intervention strategy for the intake boundary of a supercharger based on the relationship between the gear position difference of the gearbox and 0 disclosed by the embodiment of the present invention. include:

Step S201, when the current gas tank pressure is not less than the pressure threshold, it is judged whether the transmission gear difference is not equal to 0, if yes, then execute step S202;

Assuming that the current gas tank pressure is P and the pressure threshold is M, then when P≥M, it is judged that the gearbox gear difference ΔG=0 or ΔG≠0.

When △G≠0, it means that the gearbox has executed a shifting action; otherwise, when △G=0, it means that the gearbox has not executed a shifting action.

The value of the pressure threshold M is determined by the engine product type, other pressure requirements that can maintain the normal air storage tank, and the speed at which the air compressor 9 fills the air storage tank 8 .

In this embodiment, when P<M, return to step S101, and determine the transmission gear difference at the current adjacent acquisition time again.

Step S202, controlling the high-pressure supply system to start working, and the high-pressure supply system inputs high-pressure gas into the pre-pressure pipeline system of the supercharger compressor, so as to increase the gas pressure in the pre-pressure pipeline system of the supercharger compressor;

In this embodiment, when P≥M&△G≠0, it is determined that the supercharger is about to enter the transient surge working condition regardless of whether the gearbox is upshifting or downshifting. At this time, the present invention controls the high pressure supply system PSS to start working , the high-pressure gas is input from the PSS to the pipeline system 6 before the pressure of the supercharger compressor, so as to increase the gas pressure in the pipeline system 6 before the pressure of the supercharger compressor.

Specifically, when P≥M&△G≠0, in order to eliminate the surge of the supercharger, the PSS is controlled to start working. At this time, the electromagnetic control valve 7 is opened, and the high-pressure gas in the gas storage tank 8 enters the compressed air of the turbocharger. The pipeline system 6 before the pressure of the machine is used to increase the gas pressure in the pipeline system 6 before the pressure of the supercharger compressor.

Step S203, determine the engine speed difference at the current adjacent acquisition time based on the speed sampling frequency;

Two groups of engine speeds are continuously collected according to the speed sampling frequency f2, namely: n _i and n _i+1 , and the engine speed difference Δn=n _i+1 −n _i .

Step S204, judging whether the engine speed difference is greater than the preset speed difference, or the current gas tank pressure drops below the pressure threshold, or the opening time of the high pressure supply system reaches the upper limit of the opening time, if yes, Then execute step S205;

Wherein, the value of the preset rotational speed difference N is determined according to actual needs, such as 50 r/min, which is not limited in the present invention.

In this embodiment, when the engine speed difference Δn>N, the engine speed has a certain speed up from deceleration, or the current gas tank pressure P (that is, the air pressure of the gas storage tank 8) drops to the pressure threshold M Below, or when the opening time △t of the PSS reaches the upper limit of the opening time _tc , the PSS can be triggered to stop working, so that the active intervention of the supercharger intake boundary ends.

Step S205, controlling the high pressure supply system to stop working.

It should be noted that steps S201 to S205 show that when P≧M&△G≠0, a kind of supercharger intake boundary active intervention disclosed in the present invention.

In order to further optimize the above-mentioned embodiment, when P≥M&ΔG=0, the present invention shows another active intervention of the intake boundary of the supercharger.

Therefore, when step S201 judges no, it also includes:

Step S206, control the high-pressure supply system to start working, and the high-pressure supply system inputs high-pressure gas into the supercharger compressor pre-pressure pipeline system to increase the supercharger compressor pre-pressure Gas pressure in the piping system;

In this embodiment, when P≥M&△G=0, it indicates that the gearbox does not shift gears, and only the vehicle has a power reduction demand in a fixed gear. At this time, the present invention also determines that the supercharger is about to into transient surge conditions. The PSS is controlled to start working, and the PSS inputs high-pressure gas to the pipeline system 6 before the pressure of the supercharger compressor to increase the gas pressure in the pipeline system 6 before the pressure of the supercharger compressor.

Specifically, when P≥M&△G=0, in order to eliminate the surge of the supercharger, the control PSS starts to work. At this time, the electromagnetic control valve 7 is opened, and the high-pressure gas in the gas storage tank 8 enters the compressed air of the turbocharger. The pipeline system 6 before the pressure of the machine is used to increase the gas pressure in the pipeline system 6 before the pressure of the supercharger compressor.

Step S207, judging whether the current pressure of the gas tank drops below the pressure threshold, and the opening time of the high-pressure pressure supply system reaches the upper limit of the opening time, if yes, execute step S208;

In the case of P≥M&△G=0, when determining the stop time of the PSS, the engine speed is not considered, only the opening time △t of the PSS reaches the upper limit of the opening time t _c , or the current gas tank pressure (that is, the gas storage tank 8 air pressure) drops below the pressure threshold M, at this time, the PSS is triggered to stop.

Step S208, controlling the high pressure supply system to stop working.

In summary, the present invention controls in advance the start time and end time of the high-pressure supply system inputting high-pressure gas into the pipeline system before the pressure of the supercharger compressor when it is determined that the supercharger is about to enter the transient surge working condition, The purpose of eliminating the surge of the supercharger is achieved, and the surge noise of the supercharger is avoided.

In addition, compared with the traditional solution, the high-pressure gas in the pipeline after the pressure of the supercharger compressor is released to the pipeline before the pressure of the supercharger compressor, resulting in a decrease in the efficiency of the supercharger. While improving efficiency, supercharger surge (mainly transient surge) is eliminated.

Further, after the supercharger surge is eliminated in the present invention, the high-pressure gas in the pipeline after the supercharger compressor pressure continues to accumulate in the intake pipeline system after the supercharger compressor pressure, thereby improving the subsequent transient acceleration dynamics.

Corresponding to the method embodiments above, the present invention also discloses a control device for eliminating surge of a supercharger.

Referring to FIG. 4 , a schematic structural diagram of a control device for eliminating surge of a supercharger disclosed in an embodiment of the present invention, the control device is applied to the engine control unit in the embodiment shown in FIG. 1 , and the control device includes:

An acquisition unit 301, configured to acquire the current engine operating condition parameters, the current gear position of the gearbox and the current gas tank pressure;

Wherein, the current engine operating condition parameters may include: current engine speed n ₁ , current speed torque T ₁ and current speed full load torque T _1full .

The current gearbox gear is represented by G, and the current gas tank pressure is represented by P.

A torque margin determining unit 302, configured to determine the torque margin of the engine at the current transmission gear position based on the current engine operating condition parameters;

Among them, the torque margin △T is the difference between the current speed full load torque T _1full and the current speed torque T ₁ , the expression is as follows:

ΔT = T _1full - T ₁ .

A judging unit 303, configured to judge whether the torque margin is not greater than a preset torque margin when an engine power output reduction command is received;

Wherein, the value of the preset torque margin is determined according to actual needs, which is not limited in the present invention.

In this embodiment, when the engine power output reduction command is received, due to inertia, there is still high-energy exhaust gas in the exhaust pipe system 2 before the turbocharger turbocharger, and the turbocharger turbine 3 is still driven by the exhaust gas. Input power to the turbocharger compressor 5. With the reduction of the fuel supply of the engine 1, the demand for fresh air of the engine 1 decreases, and the accumulation in the pipeline system 6 before the turbocharger compressor pressure cannot be achieved in a short time. As the turbocharger speed decreases, the amount of gas in the piping system 6 before the turbocharger compressor decreases, resulting in the high pressure ratio and low flow rate of the turbocharger compressor. trend of the situation.

In practical applications, there are many ways to determine that the engine power output reduction command is received, for example, a 0% throttle opening requirement is received.

Wherein, the preset torque margin ΔT _threshold is determined based on the current rotational speed full-load torque T _1full and the surge torque coefficient K1, and the expression of the preset torque margin ΔT _threshold is as follows:

ΔT _threshold = K1*T _1full .

It should be noted that the numerical value of the surge torque coefficient K1 can reflect the severity of the surge, and the surge torque coefficient K1 is calculated in the actual application scenario of the vehicle. The value of the surge torque coefficient K1 is different under different transmission gears and different engine speeds. In the electronic control calibration program, the value of the surge torque coefficient K1 is a curve CURVE.

Examples of surge torque coefficients at different transmission gears can be found in Table 1.

A gear difference determination unit 304, configured to determine the gearbox gear difference at the current adjacent acquisition time based on the gear sampling frequency if the judging unit 303 judges yes;

According to the gear sampling frequency f1, two groups of gearbox gears are continuously collected, namely: G _i and G _i+1 , then the gear difference ΔG=G _i -G _i+1 .

An intervention strategy determination unit 305, configured to determine a corresponding supercharger intake boundary active intervention strategy based on the magnitude relationship between the gearbox gear difference and 0 when the current gas tank pressure is not less than the pressure threshold;

Wherein, the supercharger intake boundary active intervention strategy is used to control the high-pressure supply system in advance to input high-pressure gas into the pre-pressure pipeline of the supercharger compressor when it is determined that the supercharger is about to enter the transient surge condition The start time and end time of the system.

The value of the pressure threshold is determined according to needs, and the present invention does not make a limitation here.

In summary, the present invention discloses a control device for eliminating surge of a supercharger, which obtains the current engine operating condition parameters, the current gear position of the gearbox and the current gas tank pressure, and determines the engine operating condition in the current gearbox based on the current engine operating condition parameters. For the torque margin under the gear position, when the engine power output reduction command is received, if the torque margin is not greater than the preset torque margin, the gearbox gear difference at the current adjacent acquisition time is determined based on the gear position sampling frequency, and When the current tank pressure is not less than the pressure threshold, determine the corresponding supercharger intake boundary active intervention strategy based on the relationship between the gearbox gear difference and 0, so that when it is determined that the supercharger is about to enter the transient surge condition When the high-pressure pressure supply system is used to control the start time and end time of the high-pressure gas supply system inputting the high-pressure gas into the pipeline system before the pressure of the supercharger compressor, the purpose of eliminating the surge of the supercharger is achieved and the surge noise of the supercharger is avoided.

In order to further optimize the above embodiment, the intervention strategy determination unit 305 specifically includes:

A first judging subunit, configured to judge whether the gearbox gear difference is not equal to 0 when the current gas tank pressure is not less than the pressure threshold;

The first control subunit is used to control the high-pressure supply system to start working when the first determination subunit determines yes, and the high-pressure supply system inputs high-pressure gas to the supercharger The pipeline system before the pressure of the compressor is used to increase the gas pressure in the pipeline system before the pressure of the supercharger compressor;

The speed difference determination subunit is used to determine the engine speed difference at the current adjacent acquisition time based on the speed sampling frequency;

The second judging subunit is used to judge whether the engine speed difference is greater than the preset speed difference, or the current gas tank pressure drops below the pressure threshold, or the opening time of the high pressure supply system reaches open time limit;

The second control subunit is configured to control the high pressure supply system to stop working if the second judgment subunit judges yes.

In order to further optimize the above embodiment, the intervention strategy determining unit 305 may specifically include:

The third control subunit is used to control the high-pressure supply system to start working when the transmission gear difference is equal to 0, and the high-pressure supply system inputs high-pressure gas to the supercharger compressor A pre-pressure pipeline system to increase the gas pressure in the pre-pressure pipeline system of the supercharger compressor;

A third judging subunit, configured to judge whether the current gas tank pressure drops below the pressure threshold, and the opening time of the high-pressure pressure supply system reaches the upper limit of the opening time;

The fourth control subunit is configured to control the high pressure supply system to stop working if the third judging subunit judges yes.

In summary, the present invention controls in advance the start time and end time of the high-pressure supply system inputting high-pressure gas into the pipeline system before the pressure of the supercharger compressor when it is determined that the supercharger is about to enter the transient surge working condition, The purpose of eliminating the surge of the supercharger is achieved, and the surge noise of the supercharger is avoided.

In addition, compared with the traditional solution, the high-pressure gas in the pipeline after the pressure of the supercharger compressor is released to the pipeline before the pressure of the supercharger compressor, resulting in a decrease in the efficiency of the supercharger. While improving efficiency, supercharger surge (mainly transient surge) is eliminated.

Further, after the supercharger surge is eliminated in the present invention, the high-pressure gas in the pipeline after the supercharger compressor pressure continues to accumulate in the intake pipeline system after the supercharger compressor pressure, thereby improving the subsequent transient acceleration dynamics.

It should be noted that, for the specific working principle of each component in the device embodiment, please refer to the corresponding part of the method embodiment, which will not be repeated here.

Finally, it should also be noted that in this text, relational terms such as first and second etc. are only used to distinguish one entity or operation from another, and do not necessarily require or imply that these entities or operations, any such actual relationship or order exists. Furthermore, the term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus comprising a set of elements includes not only those elements, but also includes elements not expressly listed. other elements of or also include elements inherent in such a process, method, article, or device. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article or apparatus comprising said element.

Each embodiment in this specification is described in a progressive manner, each embodiment focuses on the difference from other embodiments, and the same and similar parts of each embodiment can be referred to each other.

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (11)

1. A control method for eliminating supercharger surge, characterized by being applied to an engine control unit, the control method comprising:

acquiring current engine working condition parameters, current gearbox gear and current gas tank pressure;

determining the torque allowance of the engine under the current gearbox gear based on the current engine working condition parameters;

when an engine power output reducing instruction is received, judging whether the torque margin is not larger than a preset torque margin or not;

if yes, determining a gearbox gear difference value at the current adjacent acquisition time based on the gear sampling frequency;

when the current gas tank pressure is not smaller than a pressure threshold value, determining a corresponding active intervention strategy of the air inlet boundary of the supercharger based on the magnitude relation between the gear difference value of the gearbox and 0;

the active intervention strategy of the air inlet boundary of the supercharger is used for controlling the starting time and the ending time of the high-pressure gas input to the pipeline system before the compressor of the supercharger by the high-pressure supply system in advance when the supercharger is determined to be about to enter the transient surge working condition.

2. The control method of claim 1, wherein the current engine operating condition parameters include: current engine speed, current speed torque, and current speed full torque;

the torque margin is the difference between the current rotational speed full torque and the current rotational speed torque.

3. The control method of claim 2, wherein the preset torque margin is determined based on the current rotational speed full torque and a surge torque coefficient, wherein the surge torque coefficient is different in value for different transmission gear and different engine speeds.

4. The control method of claim 1, wherein the determining a corresponding supercharger intake boundary active intervention strategy based on a magnitude relationship of the transmission gear difference value to 0 when the current tank pressure is not less than a pressure threshold value comprises:

when the current gas tank pressure is not smaller than the pressure threshold value, judging whether the gear difference value of the gearbox is not equal to 0;

if so, controlling the high-pressure supply system to start working, and inputting high-pressure gas into the pipeline system before the pressure of the supercharger compressor by the high-pressure supply system so as to increase the gas pressure in the pipeline system before the pressure of the supercharger compressor;

determining an engine speed difference value at a current adjacent acquisition time based on the speed sampling frequency;

judging whether the engine speed difference is larger than a preset speed difference, or whether the current gas tank pressure is reduced to be lower than the pressure threshold, or whether the opening time of the high-pressure supply system reaches the upper limit of the opening time;

and if so, controlling the high-pressure supply system to stop working.

5. The control method according to claim 4, characterized by further comprising:

when the gear difference value of the gearbox is equal to 0, controlling the high-pressure supply system to start working, and inputting high-pressure gas into the pipeline system before the pressure of the supercharger compressor by the high-pressure supply system so as to increase the gas pressure in the pipeline system before the pressure of the supercharger compressor;

judging whether the current gas tank pressure is reduced to be lower than the pressure threshold value, and judging whether the opening time of the high-pressure supply system reaches the upper limit of the opening time;

and if so, controlling the high-pressure supply system to stop working.

6. The control method according to claim 1, characterized in that the high-pressure supply system includes: an electromagnetic control valve, a high-pressure air storage tank and an air compressor;

the control end of the air compressor is connected with the engine, the output end of the air compressor is connected with the high-pressure air storage tank, and the high-pressure air storage tank is connected to a connecting passage of the high-pressure air storage tank and the booster compressor pre-pressure pipeline system through the electromagnetic control valve;

the control end of the electromagnetic control valve is connected with the engine control unit and used for conducting and switching on and off according to the on and off signals output by the engine control unit.

7. The control method according to claim 1, characterized in that when the current tank pressure is smaller than the pressure threshold value, the transmission gear difference value is determined again.

8. A control device for eliminating supercharger surge, characterized by being applied to an engine control unit, comprising:

the acquisition unit is used for acquiring current engine working condition parameters, current gearbox gear and current gas tank pressure;

a torque margin determining unit, configured to determine a torque margin of an engine in the current gearbox gear based on the current engine operating condition parameter;

a judging unit configured to judge whether the torque margin is not greater than a preset torque margin when an engine power output reduction instruction is received;

the gear difference value determining unit is used for determining the gear difference value of the gearbox at the current adjacent acquisition time based on the gear sampling frequency under the condition that the judging unit judges yes;

an intervention strategy determining unit, configured to determine a corresponding supercharger intake boundary active intervention strategy based on a magnitude relation between the transmission gear difference value and 0 when the current gas tank pressure is not less than a pressure threshold value;

the active intervention strategy of the air inlet boundary of the supercharger is used for controlling the starting time and the ending time of the high-pressure gas input to the pipeline system before the compressor of the supercharger by the high-pressure supply system in advance when the supercharger is determined to be about to enter the transient surge working condition.

9. The control apparatus according to claim 8, wherein the intervention policy determination unit includes:

a first judging subunit, configured to judge whether the gear difference value of the transmission is not equal to 0 when the current gas tank pressure is not less than the pressure threshold;

the first control subunit is used for controlling the high-pressure supply system to start working under the condition that the first judging subunit judges yes, and the high-pressure supply system inputs high-pressure gas into the pipeline system before the pressure of the supercharger compressor so as to increase the gas pressure in the pipeline system before the pressure of the supercharger compressor;

the rotating speed difference value determining subunit is used for determining the rotating speed difference value of the engine at the current adjacent acquisition time based on the rotating speed sampling frequency;

a second judging subunit, configured to judge whether the engine speed difference is greater than a preset speed difference, or the current gas tank pressure drops below the pressure threshold, or the opening time of the high pressure supply system reaches an upper opening time limit;

and the second control subunit is used for controlling the high-pressure supply system to stop working when the second judging subunit judges that the high-pressure supply system is in the positive state.

10. The control device according to claim 9, characterized by further comprising:

the third control subunit is used for controlling the high-pressure supply system to start working when the gear difference value of the gearbox is equal to 0, and the high-pressure supply system inputs high-pressure gas into the pipeline system before the pressure of the supercharger compressor so as to increase the gas pressure in the pipeline system before the pressure of the supercharger compressor;

a third judging subunit, configured to judge whether the current gas tank pressure falls below the pressure threshold, and the opening time of the high pressure supply system reaches the upper opening time limit;

and the fourth control subunit is used for controlling the high-pressure supply system to stop working when the third judging subunit judges yes.

11. A control system for eliminating supercharger surge, comprising: an engine, a turbocharger pre-turbo exhaust pipe system, a turbocharger turbine, a turbocharger post-turbo exhaust pipe system, a turbocharger compressor pre-compressor pipe system, an electromagnetic control valve, a high-pressure air storage tank, an air compressor, a turbocharger compressor post-compressor pipe system, and an engine control unit, wherein the engine control unit comprises the control device according to any one of claims 8 to 10;

the turbocharger compressor pre-compression pipeline system is communicated with the turbocharger compressor post-compression pipeline system through the turbocharger compressor, the turbocharger compressor post-compression pipeline system is connected with an inlet of the engine, an outlet of the engine is connected with the turbocharger pre-vortex exhaust pipeline system, and the turbocharger pre-vortex exhaust pipeline system is communicated with the turbocharger post-vortex exhaust pipeline system through the turbocharger turbine;

the control end of the air compressor is connected with the engine, the output end of the air compressor is connected with the high-pressure air storage tank, and the high-pressure air storage tank is connected to a connecting passage of the high-pressure air storage tank and the booster compressor pre-pressure pipeline system through the electromagnetic control valve;

the control end of the electromagnetic control valve is connected with the engine control unit and used for conducting and switching off according to the on-off signals output by the engine control unit;

the electromagnetic control valve, the high-pressure air storage tank and the air compressor form a high-pressure supply system.

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