Control method for an electronically controlled supercharger waste gate valve

Abstract

The application discloses a control method of an electrically-controlled supercharger exhaust bypass valve, which comprises the following steps: S1, presetting a control value of an open-loop value of the bypass valve according to each working condition of an engine in an ECU; S2, issuing an opening degree instruction of the control valve of the supercharger by the ECU according to the working condition of the engine, and pressurizing one side of the control valve through an external air source; S3, when the supercharging value reaches a limited preset value, the intake pressure drives a valve rod of the bypass valve on the other side of the control valve to act, so that the bypass valve is at a preset opening degree, which is used for adjusting the bypass amount of the exhaust gas of the supercharger and further adjusting the exhaust temperature after the turbine; and S4, calculating a closed-loop value of the bypass valve according to the deviation of the exhaust temperature after the turbine, and using the closed-loop value of the bypass valve to correct the control value of the open-loop value of the bypass valve under each working condition of the engine in real time, and finally confirming the actual opening degree of the bypass valve. Therefore, the control strategy based on different running intervals and different running environments makes the engine in an ideal running state.

Description

Technical Field

[0001] This invention relates to the field of automotive engine turbocharging technology, and in particular to a control method for an electronically controlled turbocharger exhaust bypass valve. Background Technology

[0002] The bypass valve protects the turbocharger from excessive pressure. A turbocharger consists of two parts: an exhaust turbine and a compression turbine. The exhaust turbine is connected to the exhaust manifold. When the engine reaches a certain speed, the exhaust gas has enough energy to drive the exhaust turbine to rotate. Once the exhaust turbine starts rotating, the compression turbine also rotates, compressing air and forcing it into the cylinders, thus increasing engine power. If the engine speed is too high, the pressure in the exhaust turbine will increase, and without a device, the turbine could explode. Therefore, the bypass valve exists. When the exhaust turbine pressure becomes too high, the bypass valve opens, allowing the exhaust gases to bypass the turbine and escape directly, thus preventing excessive turbine pressure.

[0003] Typical turbocharged engines are equipped with mechanical bypass valves. In traditional boost pressure control, these mechanical bypass valves open when the boost pressure exceeds a certain value under high-speed, high-load conditions. Some exhaust gas then directly enters the exhaust manifold through the bypass valve, reducing turbine speed and thus controlling boost pressure. However, this method limits the bypass valve's opening to specific conditions, resulting in inflexible control, slow response time, and the inability to continuously adjust the valve opening. It also hinders remote operation, real-time position feedback, and the inability to guarantee that the exhaust temperature after the turbocharger meets the catalytic efficiency requirements of the aftertreatment components.

[0004] Some turbocharged engines are now equipped with electronically controlled bypass valves. Their control method is based on the opening degree of the wastegate and the target boost pressure, primarily focusing on the engine's inherent performance and failing to correlate with engine emissions, thus causing the engine to operate in an undesirable state.

[0005] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to provide a control method for the exhaust gas bypass valve of an electronically controlled turbocharger, which, based on control strategies for different operating ranges and operating environments, enables the engine to operate in an ideal state.

[0007] To achieve the above objectives, the present invention provides a control method for an electronically controlled turbocharger exhaust bypass valve, comprising: Step S1, setting a control value for the bypass valve open-loop value in the ECU according to various engine operating conditions; Step S2, according to the engine operating conditions, the ECU sends an opening command to the turbocharger control valve, pressurizing one side of the control valve through an external air source; Step S3, when the boost pressure reaches a predetermined preset value, the intake pressure drives the valve stem of the bypass valve on the other side of the control valve to actuate, thereby placing the bypass valve at a preset opening degree to adjust the bypass volume of turbocharger exhaust gas and thus regulate the exhaust temperature after the turbocharger; Step S4, the control valve calculates the bypass valve closed-loop value based on the exhaust temperature deviation after the turbocharger. The bypass valve closed-loop value is used to correct the control value of the bypass valve open-loop value under various engine operating conditions in real time, and finally confirms the actual opening degree of the bypass valve.

[0008] In one embodiment of the present invention, the preset control value of the bypass valve open-loop value under various engine operating conditions is based on the current engine speed and fuel injection quantity. The original bypass valve opening control value is obtained by querying the pre-calibrated bypass valve opening basic pulse spectrum. Then, the original bypass valve opening control value is corrected for atmospheric pressure, intake air temperature and diesel engine coolant temperature to obtain the bypass valve opening open-loop control value.

[0009] In one embodiment of the present invention, the correction of the original bypass valve opening control value for atmospheric pressure, intake air temperature, and engine coolant temperature includes: correcting the atmospheric pressure according to an atmospheric pressure correction curve; correcting the intake air temperature according to an intake air temperature correction curve; and correcting the diesel engine coolant temperature according to a diesel engine coolant temperature correction curve.

[0010] In one embodiment of the present invention, the exhaust temperature deviation after the turbine is equal to the target exhaust temperature value after the turbine minus the actual exhaust temperature value after the turbine. The target exhaust temperature value after the turbine can be determined by querying the exhaust pulse spectrum of the turbine based on the current engine speed and fuel injection quantity, and the results of the test bench. Under the premise of meeting the target catalytic efficiency, the target exhaust temperature under different operating conditions is determined.

[0011] In one embodiment of the present invention, the control method of the exhaust bypass valve of the electronically controlled turbocharger further includes adjusting the opening degree of the turbocharger bypass valve by using closed-loop control of the exhaust temperature deviation after the vortex using a bypass valve PID controller. The closed-loop control value of the exhaust temperature after the vortex is added to the open-loop control value to finally obtain the target opening value of the bypass valve. The open-loop and closed-loop control functions can select the control mode of using open-loop control or open-loop control plus closed-loop control in real time according to the operating conditions.

[0012] In one embodiment of the present invention, the control valve is also used to monitor the operation of the bypass valve and finally obtain the target opening value of the bypass valve. The target opening value of the bypass valve is protected by the bypass valve opening value limit range and is converted into the bypass valve drive duty cycle through the conversion curve.

[0013] In one embodiment of the present invention, when the exhaust temperature deviation after the vortex is greater than or equal to 0, the exhaust temperature after the vortex meets the requirements of the aftertreatment component for exhaust temperature, and open-loop control continues to be performed.

[0014] In one embodiment of the present invention, when the exhaust temperature deviation after the turbine is less than 0, the exhaust temperature cannot meet the high efficiency conversion of the catalyst, which can easily cause the engine emissions to fail to meet the standards. At this time, the PID controller calculates the closed-loop value of the bypass valve opening according to the magnitude of the control deviation, and executes the control mode of open-loop control plus closed-loop control. The bypass valve closed-loop control value is added to the open-loop control value, and after being protected by the bypass valve opening value limit range, the target opening value of the bypass valve is finally obtained.

[0015] In one embodiment of the present invention, the control method of open-loop control plus closed-loop control also includes a throttle valve position control strategy. When the target opening degree of the bypass valve has exceeded the protection limit of the bypass valve opening degree limit range, the opening degree change of the bypass valve can no longer fully meet the numerical requirements of the target exhaust temperature after the turbine. In this case, the bypass valve continues to work at the limit opening degree.

[0016] Compared with the prior art, the control method of the electronically controlled turbocharger exhaust bypass valve according to the present invention, based on control strategies for different operating ranges and different operating environments, enables the engine to be in an ideal operating state. Attached Figure Description

[0017] Figure 1 This is a flowchart illustrating the control method of the exhaust gas bypass valve of an electronically controlled turbocharger according to an embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of the actual application of the control method for the exhaust gas bypass valve of the electronically controlled turbocharger according to an embodiment of the present invention.

[0019] Figure 3 This is a schematic diagram illustrating the correction of the open-loop control value of the bypass valve opening in the control method of the bypass valve of the electronically controlled turbocharger according to an embodiment of the present invention.

[0020] Figure 4 This is a schematic flowchart illustrating the control method of the exhaust gas bypass valve of an electronically controlled turbocharger according to an embodiment of the present invention. Detailed Implementation

[0021] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0022] Unless otherwise expressly stated, throughout the specification and claims, the term "comprising" or its variations such as "including" or "comprises" shall be understood to include the stated elements or components without excluding other elements or other components.

[0023] Figure 1 This is a schematic flowchart of a control method for an electronically controlled turbocharger exhaust bypass valve according to an embodiment of the present invention. Figure 2 This is a schematic diagram of the actual application of the control method for the exhaust gas bypass valve of the electronically controlled turbocharger according to an embodiment of the present invention. Figure 3 This is a schematic diagram illustrating the correction of the open-loop control value of the bypass valve opening in the control method of the bypass valve of the electronically controlled turbocharger according to an embodiment of the present invention. Figure 4 This is a schematic flowchart illustrating the control method of the exhaust gas bypass valve of an electronically controlled turbocharger according to an embodiment of the present invention.

[0024] like Figures 1 to 4 As shown, a control method for an electronically controlled turbocharger exhaust bypass valve according to a preferred embodiment of the present invention includes: Step S1, setting a control value for the bypass valve open-loop value in the ECU based on various engine operating conditions. Step S2, according to the engine operating conditions, the ECU sends an opening command to the turbocharger control valve, pressurizing one side of the control valve through an external air source. Step S3, when the boost pressure reaches a predetermined preset value, the intake pressure drives the valve stem of the bypass valve on the other side of the control valve to actuate, thereby placing the bypass valve at a preset opening degree to adjust the bypass volume of turbocharger exhaust gas and thus regulate the exhaust temperature after the turbocharger. Step S4, the control valve calculates the bypass valve closed-loop value based on the exhaust temperature deviation after the turbocharger. The bypass valve closed-loop value is used to correct the control value of the bypass valve open-loop value under various engine operating conditions in real time, and finally confirms the actual opening degree of the bypass valve.

[0025] In one embodiment of the present invention, the preset control value of the bypass valve open-loop value under various engine operating conditions is based on the current engine speed and fuel injection quantity. The original bypass valve opening control value is obtained by querying the pre-calibrated bypass valve opening basic pulse spectrum. Then, the original bypass valve opening control value is corrected for atmospheric pressure, intake air temperature and diesel engine coolant temperature to obtain the bypass valve opening open-loop control value.

[0026] In one embodiment of the present invention, the correction of the original bypass valve opening control value for atmospheric pressure, intake air temperature, and engine coolant temperature includes: correcting the atmospheric pressure according to an atmospheric pressure correction curve; correcting the intake air temperature according to an intake air temperature correction curve; and correcting the diesel engine coolant temperature according to a diesel engine coolant temperature correction curve.

[0027] In one embodiment of the present invention, the exhaust temperature deviation after the turbine is equal to the target exhaust temperature value after the turbine minus the actual exhaust temperature value after the turbine. The target exhaust temperature value after the turbine can be determined by querying the exhaust pulse spectrum of the turbine based on the current engine speed and fuel injection quantity, and the results of the test bench. Under the premise of meeting the target catalytic efficiency, the target exhaust temperature under different operating conditions is determined.

[0028] In one embodiment of the present invention, the control method of the exhaust bypass valve of the electronically controlled turbocharger further includes adjusting the opening degree of the turbocharger bypass valve by using closed-loop control of the exhaust temperature deviation after the vortex using a bypass valve PID controller. The closed-loop control value of the exhaust temperature after the vortex is added to the open-loop control value to finally obtain the target opening value of the bypass valve. The open-loop and closed-loop control functions can select the control mode of using open-loop control or open-loop control plus closed-loop control in real time according to the operating conditions.

[0029] In one embodiment of the present invention, the control valve is also used to monitor the operation of the bypass valve and finally obtain the target opening value of the bypass valve. The target opening value of the bypass valve is protected by the bypass valve opening value limit range and is converted into the bypass valve drive duty cycle through the conversion curve.

[0030] In one embodiment of the present invention, when the exhaust temperature deviation after the vortex is greater than or equal to 0, the exhaust temperature after the vortex meets the requirements of the aftertreatment component for exhaust temperature, and open-loop control continues to be performed.

[0031] In one embodiment of the present invention, when the exhaust temperature deviation after the turbine is less than 0, the exhaust temperature cannot meet the high efficiency conversion of the catalyst, which can easily cause the engine emissions to fail to meet the standards. At this time, the PID controller calculates the closed-loop value of the bypass valve opening according to the magnitude of the control deviation, and executes the control mode of open-loop control plus closed-loop control. The bypass valve closed-loop control value is added to the open-loop control value, and after being protected by the bypass valve opening value limit range, the target opening value of the bypass valve is finally obtained.

[0032] In one embodiment of the present invention, the control method of open-loop control plus closed-loop control also includes a throttle valve position control strategy. When the target opening degree of the bypass valve has exceeded the protection limit of the bypass valve opening degree limit range, the opening degree change of the bypass valve can no longer fully meet the numerical requirements of the target exhaust temperature after the turbine. In this case, the bypass valve continues to work at the limit opening degree.

[0033] In practical applications, the control method of the electronically controlled turbocharger exhaust bypass valve of this invention utilizes the flexible control characteristics of the electronically controlled exhaust valve and innovatively proposes a control strategy based on different operating ranges and operating environments, so that the engine is in an ideal operating state. Specifically, the method includes: based on development experience, the ECU sends an opening command to the turbocharger electronically controlled bypass valve device (control valve) according to the control value of the bypass valve preset for each engine operating condition. An external air source pressurizes one side of the control valve. When the pressurization value reaches a certain level, the intake pressure drives the valve stem of the bypass valve on the other side of the control valve to move, so that the bypass valve is at a preset opening degree, which is used to adjust the bypass volume of the turbocharger exhaust gas and thus regulate the exhaust temperature after the turbocharger. The bypass valve controller then calculates the closed-loop value of the bypass valve based on the exhaust temperature deviation after the turbocharger. The closed-loop value of the bypass valve is used to correct the control preset value of the bypass valve open-loop value under each engine operating condition in real time, and finally determines the actual opening degree of the bypass valve to ensure instantaneous response to the exhaust temperature after the turbocharger.

[0034] The preset control value of the bypass valve open-loop value under various engine operating conditions is based on the current engine speed and fuel injection quantity. The original bypass valve opening control value is obtained by querying the pre-calibrated bypass valve opening basic pulse spectrum. Then, the original bypass valve opening control value is corrected for atmospheric pressure, intake air temperature and diesel engine coolant temperature to obtain the bypass valve opening open-loop control value, which is the bypass valve open-loop value.

[0035] Correcting the original bypass valve opening control value for atmospheric pressure, intake air temperature, and engine coolant temperature includes: correcting for atmospheric pressure based on the atmospheric pressure correction curve; correcting for intake air temperature based on the intake air temperature correction curve; and correcting for engine coolant temperature based on the engine coolant temperature correction curve. The original bypass valve opening control value has a certain range, and the control value of the bypass valve open-loop value is within the limit range of the bypass valve opening value.

[0036] The exhaust temperature deviation after the turbine is equal to the target exhaust temperature value minus the actual exhaust temperature value. The target exhaust temperature value can be determined by looking up the exhaust pulse spectrum of the turbine exhaust based on the engine's current speed and fuel injection quantity, using bench test results. This allows for the determination of the engine's operating region while meeting the target catalytic efficiency. For a specific catalyst, there exists an optimal temperature range within which the catalyst's conversion efficiency is high and less affected by space velocity. Therefore, it is necessary to set the target temperature for different modes based on the engine's normal and heating modes. The actual exhaust temperature value T4 after the turbine is obtained by monitoring the exhaust temperature sensor.

[0037] The control method also includes adjusting the turbocharger bypass valve opening by using closed-loop control of the afterburner exhaust temperature deviation with a bypass valve PID controller. The closed-loop control value of the afterburner exhaust temperature is added to the open-loop control value to obtain the target opening value of the bypass valve. The open-loop and closed-loop control functions can select the control mode of open-loop control or open-loop control plus closed-loop control in real time according to the operating conditions. The bypass valve controller also includes a monitoring function, which monitors the operation of the bypass valve and finally obtains the target opening value of the bypass valve. The target opening value of the bypass valve is limited by the protection range of the bypass valve opening value and converted into the bypass valve drive duty cycle through a conversion curve.

[0038] When the exhaust temperature deviation after the turbine is greater than or equal to 0, the exhaust temperature after the turbine meets the requirements of the aftertreatment components for exhaust temperature, and open-loop control continues. At this time, the preset opening value is calibrated to explore the optimal fuel consumption under the explosion pressure and smoke density boundaries, and to improve the basic pulse spectrum of the bypass valve opening. When the exhaust temperature deviation after the turbine is less than 0, the exhaust temperature cannot meet the high efficiency of the catalytic converter, which can easily cause the engine emissions to fail to meet the standards. At this time, the PID controller calculates the closed-loop value of the bypass valve opening based on the magnitude of the control deviation, and executes a control mode of open-loop control plus closed-loop control. The closed-loop control value of the bypass valve is added to the open-loop control value, and after being protected by the limit range of the bypass valve opening value, the target opening value of the bypass valve is finally obtained.

[0039] The control method also includes a throttle valve position control strategy. When the target opening of the bypass valve has exceeded the protection limit of the bypass valve opening value limit range, the opening change of the bypass valve can no longer fully meet the numerical requirements of the target exhaust temperature after the turbine. In this case, the bypass valve continues to work at the limit opening, and the engine can use the throttle valve position control strategy to make up for this exhaust temperature gap and meet the catalytic efficiency of the emission aftertreatment components.

[0040] The basic principle of the control method for the exhaust gas bypass valve of the electronically controlled turbocharger of the present invention is as follows: Figure 2 As shown, the engine control unit processes the throttle signal, vehicle speed signal, and after-turbo exhaust temperature sensor signal, and transmits the bypass valve open-loop value signal under various engine operating conditions to the control unit. The electronically controlled bypass valve device, according to instructions, pressurizes one side of the control valve through an external air source. When the boost pressure reaches a predetermined level, the intake pressure drives the valve stem of the bypass valve on the other side of the control valve, causing the exhaust gas bypass valve stem to rise a certain distance to reach the required opening degree, thus adjusting the after-turbo exhaust temperature required by the engine aftertreatment components. Because the opening degree of the exhaust gas bypass valve is adjusted in real time according to the actual operating conditions of the engine, the after-turbo exhaust temperature can be regulated, and transient response is improved. The control of the turbocharger bypass valve adopts a combined feedforward and feedback control strategy based on the target after-turbo exhaust temperature T0 under various operating conditions, such as... Figure 4 As shown.

[0041] The open-loop value setting ensures that the bypass valve opening has a certain open-loop control value under various operating conditions, avoiding excessive changes in the closed-loop control quantity. The operating conditions of the diesel engine can be determined by the current engine speed and fuel injection quantity. First, based on the current engine speed and fuel quantity, the original bypass valve opening control value calculated by open-loop control is obtained by interpolation using a pre-calibrated bypass valve opening baseline pulse spectrum (MAP). Then, the original bypass valve opening control value is corrected for atmospheric pressure, intake air temperature, and diesel engine coolant temperature. The calculation process is as follows: Figure 3 As shown.

[0042] The open-loop control value of the bypass valve opening is limited between its maximum and minimum values. Closed-loop control uses a bypass valve PID controller model, calculating the control deviation between the target exhaust temperature T0 setpoint and the actual exhaust temperature, and adjusting the turbocharger bypass valve opening via PID closed-loop control. The actual exhaust temperature T4 is measured by a temperature sensor downstream of the turbocharger.

[0043] Closed-loop control enables more precise control. The target opening value of the bypass valve is obtained by adding the closed-loop value to the open-loop value. The open / closed-loop control function can select between open-loop control and a combination of open and closed-loop control based on operating conditions in real time.

[0044] The monitoring function monitors the open-loop and closed-loop control modes of the bypass valve, confirms the open-loop and closed-loop values ​​of the bypass valve, and finally obtains the target opening degree of the bypass valve. After protection and limitation, it is converted into the bypass valve drive duty cycle through the conversion curve. By pressurizing through an external air source, the valve stem of the waste gas bypass valve is driven to rise a certain distance to achieve the required opening degree. The bypass valve is adjusted to achieve the target opening degree.

[0045] The valve position signal sensor on the turbocharger's electrically controlled bypass valve monitors the actual opening position of the bypass valve and returns the actual opening value of the bypass valve to the bypass valve controller for comparison with the target opening value output of the bypass valve.

[0046] When the diesel engine is in operation, the bypass valve operates at a preset open-loop value. The open-loop control function is selected for open-loop control. The command is obtained through the duty cycle conversion curve. The bypass valve rotates a certain angle according to the command. The temperature sensor feeds back the result to obtain the exhaust temperature deviation ΔT = T4 - T0.

[0047] When ΔT≥0, the exhaust temperature after the turbine meets the requirements of the aftertreatment components for exhaust temperature, and open-loop control continues. At this time, the preset opening value can be calibrated to explore the optimal fuel consumption under the boundary conditions of explosion pressure, smoke, etc., and improve the basic pulse spectrum (MAP) of the bypass valve opening.

[0048] When ΔT < 0, the exhaust temperature cannot meet the catalytic efficiency requirements, which can easily lead to engine emissions failing to meet standards. At this time, the PID controller calculates the closed-loop value of the bypass valve opening based on the magnitude of the control deviation, and executes an open-loop + closed-loop control mode. The bypass valve closed-loop value is added to the bypass valve open-loop value, and after protection limiting, the target opening value of the bypass valve is finally obtained.

[0049] The open-loop + closed-loop control method also includes: when the target opening of the bypass valve has exceeded the protection limit, the opening change of the bypass valve can no longer fully meet the numerical requirement of the target exhaust temperature T0. In this case, the bypass valve continues to work at the limit opening, and the engine should use other strategies, such as the "throttle valve position control strategy", to make up for this exhaust temperature gap and meet the catalytic efficiency of the emission aftertreatment components.

[0050] When the engine accelerates, to ensure the engine's rapid demand for intake air, the bypass valve should be fully closed under this condition to improve the turbocharger's transient response. Conversely, when decelerating or braking, the bypass valve should be fully open to bypass most of the exhaust gas and reduce the turbocharger's work.

[0051] In summary, the control method for the exhaust gas bypass valve of the electronically controlled turbocharger of the present invention has the following beneficial effects:

[0052] The engine control unit processes the throttle signal, vehicle speed signal, and exhaust temperature sensor signal from the after-turbocharger. It then combines the preset control opening value of the bypass valve under various engine operating conditions with the closed-loop value of the bypass valve opening calculated by the bypass valve PID controller based on the control deviation. This is achieved through an open-loop + closed-loop control method. After protection and limiting, the target opening value of the bypass valve is transmitted to the control unit. The electronically controlled bypass valve device, according to the command, drives the exhaust bypass valve stem to rise a certain distance to achieve the required opening, adjusting the exhaust temperature required by the engine aftertreatment components. Based on control strategies for different operating ranges and environments, the engine can operate in an ideal state.

[0053] The foregoing description of specific exemplary embodiments of the invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. The scope of the invention is intended to be defined by the claims and their equivalents.

Claims

1. A control method of an electrically controlled supercharger waste gate valve, characterized by, The method comprises the following steps: Step S1, presetting the control value of the open-loop value of the bypass valve according to the working condition of the engine in the ECU; Step S2, issuing the opening degree instruction of the control valve of the supercharger by the ECU according to the working condition of the engine, and pressurizing one side of the control valve through an external air source; Step S3, when the supercharging value reaches the predefined preset value, the intake pressure drives the valve rod of the bypass valve on the other side of the control valve to act, so that the bypass valve is at a preset opening degree, so as to adjust the bypass amount of the exhaust gas of the supercharger and further adjust the exhaust temperature after the turbine; Step S4, the control valve calculates the closed-loop value of the bypass valve according to the deviation of the exhaust temperature after the turbine, and the closed-loop value of the bypass valve is used to correct the control value of the open-loop value of the bypass valve under each working condition of the engine in real time, and finally confirm the actual opening degree of the bypass valve; Wherein, the control value of the open-loop value of the bypass valve under each working condition of the engine is based on the current speed and fuel injection amount of the engine, and the original bypass valve opening degree control value is obtained by querying the pre-marked bypass valve opening degree basic map, and then the original bypass valve opening degree control value is corrected by atmospheric pressure, intake temperature and diesel engine coolant temperature to obtain the bypass valve opening degree open-loop control value; Wherein, the correction of the original bypass valve opening degree control value by atmospheric pressure, intake temperature and engine coolant temperature comprises: correcting the atmospheric pressure according to the atmospheric pressure correction curve; correcting the intake temperature according to the intake temperature correction curve; and correcting the diesel engine coolant temperature according to the diesel engine coolant temperature correction curve.

2. The control method of an electrically controlled supercharger waste gate valve according to claim 1, characterized by, The deviation of the exhaust temperature after the turbine is equal to the target exhaust temperature after the turbine minus the actual exhaust temperature after the turbine, and the target exhaust temperature after the turbine can be obtained by querying the exhaust temperature after the turbine map based on the bench test results according to the current speed and fuel injection amount of the engine, and the target exhaust temperature after the turbine is determined in the region of engine operation under the premise of meeting the target catalytic efficiency.

3. The control method of an electrically controlled supercharger waste gate valve according to claim 2, characterized by, Further comprising that the deviation of the exhaust temperature after the turbine is adjusted by the open degree of the bypass valve of the supercharger through the closed-loop control of the bypass valve PID controller, the closed-loop control value of the exhaust temperature after the turbine is added to the open-loop control value, and finally the target opening degree value of the bypass valve is obtained, and the open-loop control or open-loop control plus closed-loop control control mode can be selected according to the working condition.

4. The control method of an electrically controlled supercharger waste gate valve according to claim 1, characterized by, The control valve is also used to monitor the working condition of the bypass valve, and finally the target opening degree value of the bypass valve is obtained, which is protected and limited by the bypass valve opening degree value limit range, and is converted into the bypass valve driving duty cycle through the conversion curve.

5. The control method of an electrically controlled supercharger waste gate valve according to claim 1, characterized by, When the deviation of the exhaust temperature after the turbine is greater than or equal to 0, the exhaust temperature after the turbine meets the requirement of the catalytic effect of the aftertreatment component on the exhaust temperature, and the open-loop control is continued to be executed.

6. The control method of an electrically controlled supercharger waste gate valve according to claim 5, characterized in that, When the deviation of the exhaust temperature after the turbine is less than 0, the exhaust temperature cannot meet the high conversion efficiency of the catalyst, which is easy to cause the engine emission to be unqualified, at this time, the PID controller calculates the closed-loop value of the opening degree of the bypass valve according to the control deviation, executes the control mode of open-loop control plus closed-loop control, adds the closed-loop control value of the bypass valve to the open-loop control value, and finally obtains the target opening degree value of the bypass valve through the protection and limitation of the bypass valve opening degree value limit range.

7. The control method of an electrically controlled supercharger waste gate valve according to claim 3, characterized by, The control mode of the open-loop control plus the closed-loop control further comprises a throttle valve position control strategy, when the bypass valve target opening has exceeded the protection limit of the bypass valve opening value limit range, at this time the opening change of the bypass valve cannot completely meet the value requirement of the target exhaust gas temperature after the turbine, the bypass valve continues to work at the limit opening.

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