Supercharger overspeed protection method, device, equipment and readable storage medium

Abstract

A supercharger overspeed protection method, device, equipment and readable storage medium, the supercharger overspeed protection method includes: when detecting that the supercharger pressurizes, according to the gas engine rotating speed, atmospheric pressure and first calibration relation table, the maximum duty cycle of the supercharger exhaust gas bypass electromagnetic valve is determined;The maximum duty cycle is corrected using the rotating speed change rate correction parameter and the intake temperature correction parameter of the maximum duty cycle, and the corrected value of the maximum duty cycle is obtained;If the duty cycle of the supercharger exhaust gas bypass electromagnetic valve is greater than the corrected value of the maximum duty cycle, then the duty cycle of the supercharger exhaust gas bypass electromagnetic valve is controlled to be the corrected value of the maximum duty cycle, to limit the rotating speed of the supercharger.The application is limited to different gas engine rotating speed, rotating speed change rate, atmospheric pressure and intake temperature, and the maximum rotating speed of the supercharger is limited by limiting the maximum duty cycle of the exhaust gas bypass electromagnetic valve, to protect the rotating speed of the supercharger from overspeed and avoid the damage of the supercharger.

Description

Technical Field

[0001] This application relates to the field of turbocharger safety technology, and in particular to a turbocharger overspeed protection method, device, equipment and readable storage medium. Background Technology

[0002] A gas engine is an engine that uses various gaseous fuels to operate. The gas engine turbocharger compresses the air entering the gas engine cylinder to increase its density, allowing more air to enter the cylinder and thus increasing the engine's power. The turbocharger controls the turbocharger's boost capacity by controlling the duty cycle of the exhaust bypass solenoid valve to adjust the valve opening.

[0003] When there is air leakage in the gas engine's intake system or deviations in the measurement of the boost pressure sensor, the actual boost pressure of the booster may not reach the target boost pressure. The booster will increase its speed by increasing the duty cycle of the exhaust bypass solenoid valve in order to increase the boost pressure. However, this may lead to the risk of the booster speed exceeding the limit, which could easily damage the booster. Summary of the Invention

[0004] This application provides a method, apparatus, device, and readable storage medium for overspeed protection of a turbocharger, aiming to solve the technical problem that the turbocharger may be at risk of overspeeding under certain circumstances, and the turbocharger may be easily damaged.

[0005] In a first aspect, embodiments of this application provide a turbocharger overspeed protection method, the turbocharger overspeed protection method comprising:

[0006] When turbocharger boost is detected, the maximum duty cycle of the turbocharger exhaust bypass solenoid valve is determined based on the gas engine speed, atmospheric pressure, and the first calibration relationship table.

[0007] Based on the gas engine speed change rate and the second calibration relationship table, determine the speed change rate correction parameter for the maximum duty cycle;

[0008] Based on the gas engine speed, intake air temperature, and the third calibration relationship table, determine the intake air temperature correction parameter for the maximum duty cycle;

[0009] The maximum duty cycle is corrected using the speed change rate correction parameter and the intake air temperature correction parameter to obtain the corrected value of the maximum duty cycle.

[0010] If the duty cycle of the turbocharger exhaust bypass solenoid valve is greater than the correction value of the maximum duty cycle, then the duty cycle of the turbocharger exhaust bypass solenoid valve is controlled to the correction value of the maximum duty cycle in order to limit the speed of the turbocharger.

[0011] Optionally, the turbocharger overspeed protection method further includes:

[0012] When turbocharger boost is detected, the correction parameters of the turbocharger PID controller are determined based on the gas engine speed change rate and the fourth calibration relationship table.

[0013] The current output parameters of the turbocharger PID controller are corrected using the correction parameters of the turbocharger PID controller to obtain the basic duty cycle of the turbocharger exhaust bypass solenoid valve. The current output parameters of the turbocharger PID controller are determined based on the gas engine speed, pressure difference, and the fifth calibration relationship table. The fifth calibration relationship table includes the correspondence between different gas engine speeds, pressure differences, and the current output parameters of the turbocharger PID controller. The pressure difference is the difference between the actual boost pressure and the target boost pressure.

[0014] The duty cycle of the turbocharger exhaust bypass solenoid valve is controlled by the smaller of the base duty cycle and the maximum duty cycle correction value, in order to limit the turbocharger speed.

[0015] Optionally, the first calibration relationship table includes the correspondence between different gas engine speeds, atmospheric pressures, and the maximum duty cycle of the turbocharger exhaust bypass solenoid valve. The steps for determining the first calibration relationship table include:

[0016] For each combination of gas engine speed and atmospheric pressure, the load on the gas engine is increased to full load;

[0017] The duty cycle of the exhaust bypass solenoid valve when the turbocharger speed reaches the preset overspeed threshold is taken as the maximum duty cycle of the turbocharger exhaust bypass solenoid valve corresponding to each combination of gas engine speed and atmospheric pressure.

[0018] Optionally, the second calibration relationship table includes the correspondence between different gas engine speed change rates and the speed change rate correction parameter for maximum duty cycle. The steps for determining the second calibration relationship table include:

[0019] Under standard atmospheric pressure, for each gas engine speed change rate, the gas engine is pulled up from idle condition to full load at multiple preset gas engine speeds according to the gas engine speed change rate. The duty cycle of the exhaust bypass solenoid valve when the turbocharger speed reaches the preset overspeed threshold is taken as the maximum duty cycle of the exhaust bypass solenoid valve at each preset gas engine speed.

[0020] The minimum value of the maximum duty cycle of the exhaust bypass solenoid valve at each preset gas engine speed is taken as the maximum duty cycle of the exhaust bypass solenoid valve at each gas engine speed change rate.

[0021] Divide the maximum duty cycle of the exhaust bypass solenoid valve under each gas engine speed change rate by the maximum duty cycle during steady-state operation of the gas engine to obtain the speed change rate correction parameter corresponding to the maximum duty cycle of each gas engine speed change rate.

[0022] Optionally, the third calibration relationship table includes the correspondence between different gas engine speeds, intake air temperatures, and intake air temperature correction parameters for maximum duty cycles. The steps for determining the third calibration relationship table include:

[0023] Under standard atmospheric pressure, for each combination of gas engine speed and intake air temperature, the load of the gas engine is increased to full load;

[0024] The duty cycle of the exhaust bypass solenoid valve when the turbocharger speed reaches the preset overspeed threshold is taken as the maximum duty cycle of the turbocharger exhaust bypass solenoid valve for each combination of gas engine speed and intake air temperature.

[0025] Divide the maximum duty cycle of the turbocharger exhaust bypass solenoid valve for each combination of gas engine speed and intake air temperature by the maximum duty cycle of the turbocharger exhaust bypass solenoid valve for the same combination of gas engine speed and preset reference intake air temperature to obtain the intake air temperature correction parameter corresponding to the maximum duty cycle of each combination of gas engine speed and intake air temperature.

[0026] Optionally, the fourth calibration relationship table includes the correspondence between different gas engine speed change rates and the correction parameters of the turbocharger PID controller. The steps for determining the fourth calibration relationship table include:

[0027] For each gas engine speed change rate, the gas engine is increased from idle to full load at multiple preset gas engine speeds according to the gas engine speed change rate. The output parameters of the turbocharger PID controller when the turbocharger speed reaches the preset overspeed threshold are used as the output parameters of the turbocharger PID controller at each preset gas engine speed.

[0028] The minimum value among the output parameters of the turbocharger PID controller at each preset gas engine speed is used as the output parameter of the turbocharger PID controller at each gas engine speed change rate.

[0029] Divide the output parameter of the turbocharger PID controller at each gas engine speed change rate by the output parameter of the turbocharger PID controller during steady-state operation of the gas engine to obtain the correction parameter of the turbocharger PID controller corresponding to each gas engine speed change rate.

[0030] Secondly, embodiments of this application provide a turbocharger overspeed protection device, the turbocharger overspeed protection device comprising:

[0031] The first determining module is used to determine the maximum duty cycle of the turbocharger exhaust bypass solenoid valve based on the gas engine speed, atmospheric pressure and the first calibration relationship table when turbocharger boost is detected.

[0032] The second determining module is used to determine the speed change rate correction parameter for the maximum duty cycle based on the gas engine speed change rate and the second calibration relationship table.

[0033] The third determination module is used to determine the intake temperature correction parameter for the maximum duty cycle based on the gas engine speed, intake temperature and the third calibration relationship table;

[0034] The correction module is used to correct the maximum duty cycle using the speed change rate correction parameter and the intake air temperature correction parameter to obtain the corrected value of the maximum duty cycle.

[0035] The first control module is used to control the duty cycle of the turbocharger exhaust bypass solenoid valve to the correction value of the maximum duty cycle if the duty cycle of the turbocharger exhaust bypass solenoid valve is greater than the correction value of the maximum duty cycle, so as to limit the speed of the turbocharger.

[0036] Optionally, the turbocharger overspeed protection device further includes a second control module for:

[0037] When turbocharger boost is detected, the correction parameters of the turbocharger PID controller are determined based on the gas engine speed change rate and the fourth calibration relationship table.

[0038] The current output parameters of the turbocharger PID controller are corrected using the correction parameters of the turbocharger PID controller to obtain the basic duty cycle of the turbocharger exhaust bypass solenoid valve. The current output parameters of the turbocharger PID controller are determined based on the gas engine speed, pressure difference, and the fifth calibration relationship table. The fifth calibration relationship table includes the correspondence between different gas engine speeds, pressure differences, and the current output parameters of the turbocharger PID controller. The pressure difference is the difference between the actual boost pressure and the target boost pressure.

[0039] The duty cycle of the turbocharger exhaust bypass solenoid valve is controlled by the smaller of the base duty cycle and the maximum duty cycle correction value, in order to limit the turbocharger speed.

[0040] Thirdly, this application provides a turbocharger overspeed protection device, which includes a processor, a memory, and a turbocharger overspeed protection program stored in the memory and executable by the processor. When the turbocharger overspeed protection program is executed by the processor, it implements the steps of the turbocharger overspeed protection method as described above.

[0041] Fourthly, embodiments of this application provide a readable storage medium storing a turbocharger overspeed protection program, wherein when the turbocharger overspeed protection program is executed by a processor, it implements the steps of the turbocharger overspeed protection method as described above.

[0042] The beneficial effects of the technical solutions provided in this application include:

[0043] In this embodiment, when turbocharger boost is detected, the maximum duty cycle of the turbocharger exhaust bypass solenoid valve is determined based on the gas engine speed, atmospheric pressure, and a first calibration relationship table; the speed change rate correction parameter for the maximum duty cycle is determined based on the gas engine speed change rate and a second calibration relationship table; the intake temperature correction parameter for the maximum duty cycle is determined based on the gas engine speed, intake air temperature, and a third calibration relationship table; the maximum duty cycle is corrected using the speed change rate correction parameter and the intake air temperature correction parameter to obtain a corrected value for the maximum duty cycle; if the duty cycle of the turbocharger exhaust bypass solenoid valve is greater than the corrected value for the maximum duty cycle, the duty cycle of the turbocharger exhaust bypass solenoid valve is controlled to be the corrected value for the maximum duty cycle to limit the turbocharger speed. This application embodiment uses the maximum duty cycle of the turbocharger's exhaust bypass solenoid valve at the current gas engine speed and atmospheric pressure as a basis. The maximum duty cycle is then corrected based on the gas engine's speed change rate and intake air temperature to obtain a corrected value, which serves as the output of the turbocharger's PID controller. This allows for the limitation of the turbocharger's maximum speed by restricting the maximum duty cycle of the exhaust bypass solenoid valve for different gas engine speeds, speed change rates, atmospheric pressures, and intake air temperatures. Even in situations such as air leakage in the intake system or deviations in the boost pressure sensor measurement, the turbocharger's speed can be kept within a safe range, preventing overspeeding and damage. Attached Figure Description

[0044] Figure 1 This is a flowchart illustrating an embodiment of the turbocharger overspeed protection method of this application;

[0045] Figure 2 This is another flowchart illustrating an embodiment of the turbocharger overspeed protection method of this application;

[0046] Figure 3 This is a schematic diagram of the overall control logic of an embodiment of the turbocharger overspeed protection method of this application;

[0047] Figure 4 This is a functional module diagram of an embodiment of the turbocharger overspeed protection device of this application;

[0048] Figure 5 This is a schematic diagram of the hardware structure of the turbocharger overspeed protection device involved in the embodiments of this application. Detailed Implementation

[0049] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0050] The terms "comprising" and "having," and any variations thereof, in the specification, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus. The terms "first," "second," and "third," etc., are used to distinguish different objects, etc., and do not indicate a sequence, nor do they limit "first," "second," and "third" to different types.

[0051] In the description of the embodiments of this application, terms such as "exemplary," "for example," or "for instance" are used to indicate examples, illustrations, or explanations. Any embodiment or design described as "exemplary," "for example," or "for instance" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary," "for example," or "for instance" is intended to present the relevant concepts in a concrete manner.

[0052] In the description of the embodiments of this application, unless otherwise stated, " / " means "or". For example, A / B can mean A or B. The "and / or" in the text is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of this application, "multiple" means two or more.

[0053] In some processes described in the embodiments of this application, multiple operations or steps are included in a specific order. However, it should be understood that these operations or steps may not be executed in the order they appear in the embodiments of this application, or they may be executed in parallel. The sequence number of the operation is only used to distinguish different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed sequentially or in parallel, and these operations or steps may be combined.

[0054] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0055] In a first aspect, embodiments of this application provide a method for overspeed protection of a turbocharger.

[0056] In one embodiment, reference is made to Figure 1 , Figure 1 This is a flowchart illustrating an embodiment of the turbocharger overspeed protection method of this application, as shown below. Figure 1 As shown, the overspeed protection method for the turbocharger includes:

[0057] Step S10: When the turbocharger is detected to be pressurized, the maximum duty cycle of the turbocharger exhaust bypass solenoid valve is determined according to the gas engine speed, atmospheric pressure and the first calibration relationship table.

[0058] In this embodiment, the gas engine speed and atmospheric pressure are the current gas engine speed and atmospheric pressure of the vehicle. The atmospheric pressure varies depending on the altitude of the vehicle's location. When turbocharger boost is detected, to prevent the turbocharger speed from overspeeding, the first calibration relationship table is consulted based on the current gas engine speed and atmospheric pressure to obtain the maximum duty cycle of the turbocharger exhaust bypass solenoid valve corresponding to the current gas engine speed and atmospheric pressure. The first calibration relationship table is shown in Table 1. In Table 1, x represents the gas engine speed in r / min and y represents the atmospheric pressure in kPa. The value corresponding to the gas engine speed x and atmospheric pressure y in Table 1 is the maximum duty cycle of the turbocharger exhaust bypass solenoid valve.

[0059] Table 1.

[0060]

[0061]

[0062] Step S20: Determine the speed change rate correction parameter for the maximum duty cycle based on the gas engine speed change rate and the second calibration relationship table.

[0063] In this embodiment, the second calibration relationship table is consulted based on the current gas engine speed change rate to obtain the speed change rate correction parameter for the maximum duty cycle corresponding to the current gas engine speed change rate. The second calibration relationship table is shown in Table 2. In Table 2, x represents the gas engine speed change rate in r / s, and z represents the speed change rate correction parameter for the maximum duty cycle.

[0064] Table 2.

[0065] x 0 50 100 150 200 300 z 1 1 0.98 0.97 0.96 0.95

[0066] Step S30: Determine the intake temperature correction parameter for the maximum duty cycle based on the gas engine speed, intake temperature, and the third calibration relationship table.

[0067] In this embodiment, the third calibration relationship table is consulted based on the current gas engine speed and intake air temperature to obtain the intake air temperature correction parameter for the maximum duty cycle corresponding to the current gas engine speed and intake air temperature. The third calibration relationship table is shown in Table 3. In Table 3, x represents the gas engine speed in r / min and y represents the intake air temperature in °C. The values ​​corresponding to the gas engine speed x and intake air temperature y in Table 3 are the intake air temperature correction parameters for the maximum duty cycle.

[0068] Table 3.

[0069]

[0070] Step S40: Correct the maximum duty cycle using the speed change rate correction parameter and the intake air temperature correction parameter to obtain the corrected value of the maximum duty cycle.

[0071] In this embodiment, the maximum duty cycle is corrected using the speed change rate correction parameter and the intake air temperature correction parameter. The corrected value of the maximum duty cycle is calculated using the formula: Ldtv maxcor =Ldtv max ×Co ldtvr ×Co Tintk Among them, Ldtv maxcor Ldtv is the correction value for the maximum duty cycle. max For maximum duty cycle, Co ldtvr Co is the parameter for correcting the rate of change of rotational speed. Tintk This is the parameter for correcting the intake air temperature.

[0072] Step S50: If the duty cycle of the turbocharger exhaust bypass solenoid valve is greater than the correction value of the maximum duty cycle, then control the duty cycle of the turbocharger exhaust bypass solenoid valve to the correction value of the maximum duty cycle in order to limit the speed of the turbocharger.

[0073] In this embodiment, if the duty cycle of the turbocharger exhaust bypass solenoid valve is greater than the correction value of the maximum duty cycle, it indicates that there is a risk of overspeeding of the turbocharger. In this case, the duty cycle of the turbocharger exhaust bypass solenoid valve is controlled to be the correction value of the maximum duty cycle. Conversely, if the duty cycle of the turbocharger exhaust bypass solenoid valve is less than or equal to the correction value of the maximum duty cycle, it indicates that there is no risk of overspeeding of the turbocharger. Therefore, there is no need to limit the duty cycle of the turbocharger exhaust bypass solenoid valve. Thus, by limiting the duty cycle of the turbocharger exhaust bypass solenoid valve, the purpose of limiting the turbocharger speed is achieved, protecting the turbocharger from overspeeding and avoiding damage to the turbocharger.

[0074] In this embodiment, based on the maximum duty cycle of the turbocharger exhaust bypass solenoid valve under the current gas engine speed and atmospheric pressure, the maximum duty cycle is corrected according to the gas engine speed change rate and intake air temperature to obtain a corrected value for the maximum duty cycle. If the duty cycle of the turbocharger exhaust bypass solenoid valve is greater than the corrected value for the maximum duty cycle, it indicates that there is a risk of overspeeding of the turbocharger. Therefore, the duty cycle of the turbocharger exhaust bypass solenoid valve is controlled to be the corrected value for the maximum duty cycle. Thus, for different gas engine speeds, speed change rates, atmospheric pressures, and intake air temperatures, the maximum speed of the turbocharger is limited by restricting the maximum duty cycle of the exhaust bypass solenoid valve. This ensures that even in situations such as air leakage in the intake system or deviations in the boost pressure sensor measurement, the turbocharger speed can operate within a safe range, protecting the turbocharger from overspeeding and preventing damage to the turbocharger.

[0075] Furthermore, in one embodiment, reference is made to Figure 2 , Figure 2 This is another schematic flowchart of an embodiment of the turbocharger overspeed protection method of this application, as shown below. Figure 2 As shown, the turbocharger overspeed protection method further includes:

[0076] Step S01: When turbocharger boost is detected, determine the correction parameters of the turbocharger PID controller according to the gas engine speed change rate and the fourth calibration relationship table;

[0077] Step S02: Correct the current output parameters of the turbocharger PID controller using the correction parameters of the turbocharger PID controller to obtain the basic duty cycle of the turbocharger exhaust bypass solenoid valve. The current output parameters of the turbocharger PID controller are determined based on the gas engine speed, pressure difference, and the fifth calibration relationship table. The fifth calibration relationship table includes the correspondence between different gas engine speeds, pressure differences, and the current output parameters of the turbocharger PID controller. The pressure difference is the difference between the actual boost pressure and the target boost pressure.

[0078] Step S03: Control the duty cycle of the turbocharger exhaust bypass solenoid valve to the smaller of the base duty cycle and the maximum duty cycle correction value, so as to limit the speed of the turbocharger.

[0079] In this embodiment, when turbocharger boost is detected, the fourth calibration relationship table is consulted based on the current gas engine speed change rate to obtain the correction parameters of the turbocharger PID controller corresponding to the current gas engine speed change rate. The fourth calibration relationship table is shown in Table 4. In Table 4, x represents the gas engine speed change rate in r / s, and z represents the correction parameters of the turbocharger PID controller. Because the response of turbocharger pressure is generally lagging behind that of throttle response, a larger output parameter of the PID controller is usually used to ensure its responsiveness during turbocharger control calibration (i.e., calibration of the fifth calibration table). When the actual boost pressure of the gas engine during acceleration is less than the target boost pressure, the integral KI is accumulated. When the actual boost pressure is greater than the target boost pressure, the integral KI is gradually reduced to reduce control error. The lag in the adjustment of the integral KI leads to boost pressure overshoot during transient acceleration and deceleration of the gas engine, which can easily lead to the risk of turbocharger speed overspeed. Therefore, considering the problem of transient turbocharger response lag, a transient correction pre-control is applied to the turbocharger in advance according to the actual operating conditions of the gas engine. This can better prevent turbocharger speed overspeed. Specifically, the correction parameters of the turbocharger PID controller are determined according to the gas engine speed change rate and the fourth calibration table, and the current output parameters of the turbocharger PID controller are corrected using the correction parameters of the turbocharger PID controller. Furthermore, the actual boost pressure can be measured by placing a pressure sensor on a pipe close to the engine intake manifold (after the intercooler) to measure the boost pressure after intercooling. Further, considering the correction value for the maximum duty cycle, the smaller of the base duty cycle and the correction value for the maximum duty cycle can be selected as the duty cycle of the turbocharger exhaust bypass solenoid valve to better limit the turbocharger speed, ensuring that the turbocharger speed does not exceed the limit and preventing turbocharger damage. In summary, the overall control logic for the duty cycle of the turbocharger exhaust bypass solenoid valve in this invention can be referred to... Figure 3 , Figure 3 This is a schematic diagram of the overall control logic of an embodiment of the turbocharger overspeed protection method of this application.

[0080] Table 4.

[0081] x 0 50 100 150 200 300 z 1 1 0.98 0.95 0.93 0.9

[0082] Further, in one embodiment, the first calibration relationship table includes the correspondence between different gas engine speeds, atmospheric pressures, and the maximum duty cycle of the turbocharger exhaust bypass solenoid valve. The steps for determining the first calibration relationship table include:

[0083] For each combination of gas engine speed and atmospheric pressure, the load on the gas engine is increased to full load;

[0084] The duty cycle of the exhaust bypass solenoid valve when the turbocharger speed reaches the preset overspeed threshold is taken as the maximum duty cycle of the turbocharger exhaust bypass solenoid valve corresponding to each combination of gas engine speed and atmospheric pressure.

[0085] In this embodiment, the operation of the gas engine under different atmospheric pressures can be simulated by controlling the engine intake manifold pressure. Referring to Table 1, for each combination of gas engine speed and atmospheric pressure, the load of the gas engine is increased to full load. The duty cycle of the exhaust bypass solenoid valve when the turbocharger speed reaches the preset overspeed threshold is the maximum duty cycle of the turbocharger exhaust bypass solenoid valve corresponding to each combination of gas engine speed and atmospheric pressure. The preset overspeed threshold is the highest speed at which the turbocharger can operate safely under the corresponding conditions. This value can be obtained from the turbocharger manufacturer.

[0086] Further, in one embodiment, the second calibration relationship table includes the correspondence between different gas engine speed change rates and the speed change rate correction parameter for maximum duty cycle, and the steps for determining the second calibration relationship table include:

[0087] Under standard atmospheric pressure, for each gas engine speed change rate, the gas engine is pulled up from idle condition to full load at multiple preset gas engine speeds according to the gas engine speed change rate. The duty cycle of the exhaust bypass solenoid valve when the turbocharger speed reaches the preset overspeed threshold is taken as the maximum duty cycle of the exhaust bypass solenoid valve at each preset gas engine speed.

[0088] The minimum value of the maximum duty cycle of the exhaust bypass solenoid valve at each preset gas engine speed is taken as the maximum duty cycle of the exhaust bypass solenoid valve at each gas engine speed change rate.

[0089] Divide the maximum duty cycle of the exhaust bypass solenoid valve under each gas engine speed change rate by the maximum duty cycle during steady-state operation of the gas engine to obtain the speed change rate correction parameter corresponding to the maximum duty cycle of each gas engine speed change rate.

[0090] In this embodiment, under standard atmospheric pressure, the rate of change of each gas engine speed is tested and calibrated according to the following steps: Based on the rate of change of gas engine speed, such as 80 r / s, the gas engine is increased from idle speed (e.g., 600 rpm, 0 load) to full load at several preset gas engine speeds, such as 1000 rpm, 1200 rpm, 1400 rpm, 1600 rpm, and 1800 rpm, until the turbocharger speed reaches a preset overspeed threshold. The speeds at 1000 rpm, 1200 rpm, and 1400 rpm are recorded. The duty cycle of the exhaust bypass solenoid valve at full load of 1000 rpm, 1200 rpm, 1400 rpm, 1600 rpm, and 1800 rpm is taken as the minimum duty cycle of the exhaust bypass solenoid valve at full load of 1000 rpm, 1200 rpm, 1400 rpm, 1600 rpm, and 1800 rpm. This minimum value is then taken as the maximum duty cycle of the exhaust bypass solenoid valve at a speed change rate of 80 rpm. This minimum value is then divided by the maximum duty cycle during steady-state operation (e.g., a speed change rate within 50 rpm). This gives the speed change rate correction parameter for the maximum duty cycle at a speed change rate of 80 rpm.

[0091] Further, in one embodiment, the third calibration relationship table includes the correspondence between different gas engine speeds, intake air temperatures, and intake air temperature correction parameters for maximum duty cycles. The steps for determining the third calibration relationship table include:

[0092] Under standard atmospheric pressure, for each combination of gas engine speed and intake air temperature, the load of the gas engine is increased to full load;

[0093] The duty cycle of the exhaust bypass solenoid valve when the turbocharger speed reaches the preset overspeed threshold is taken as the maximum duty cycle of the turbocharger exhaust bypass solenoid valve for each combination of gas engine speed and intake air temperature.

[0094] Divide the maximum duty cycle of the turbocharger exhaust bypass solenoid valve for each combination of gas engine speed and intake air temperature by the maximum duty cycle of the turbocharger exhaust bypass solenoid valve for the same combination of gas engine speed and preset reference intake air temperature to obtain the intake air temperature correction parameter corresponding to the maximum duty cycle of each combination of gas engine speed and intake air temperature.

[0095] In this embodiment, since different temperatures affect air density, the actual intake air volume required for a certain engine operating condition is constant. Because intake air temperature affects intake air density, the actual operating state of the turbocharger varies with the intake air temperature for the same intake air volume requirement. Therefore, it is essential to correct the maximum duty cycle of the turbocharger's exhaust gas bypass solenoid valve based on the real-time intake air temperature. Referring to Table 3, under standard atmospheric pressure, for each combination of gas engine speed and intake air temperature, the gas engine load is increased to full load. The duty cycle of the exhaust gas bypass solenoid valve when the turbocharger speed reaches the preset overspeed threshold is the maximum duty cycle of the turbocharger's exhaust gas bypass solenoid valve for each combination of gas engine speed and intake air temperature. The preset reference intake temperature is, for example, 25°C. The maximum duty cycle of the turbocharger exhaust bypass solenoid valve for each combination of gas engine speed and intake temperature is divided by the maximum duty cycle of the turbocharger exhaust bypass solenoid valve under the combination of gas engine speed and 25°C. This yields the intake temperature correction parameter corresponding to the maximum duty cycle of each combination of gas engine speed and intake temperature.

[0096] Furthermore, in one embodiment, the fourth calibration relationship table includes the correspondence between different gas engine speed change rates and the correction parameters of the turbocharger PID controller, and the steps for determining the fourth calibration relationship table include:

[0097] For each gas engine speed change rate, the gas engine is increased from idle to full load at multiple preset gas engine speeds according to the gas engine speed change rate. The output parameters of the turbocharger PID controller when the turbocharger speed reaches the preset overspeed threshold are used as the output parameters of the turbocharger PID controller at each preset gas engine speed.

[0098] The minimum value among the output parameters of the turbocharger PID controller at each preset gas engine speed is used as the output parameter of the turbocharger PID controller at each gas engine speed change rate.

[0099] Divide the output parameter of the turbocharger PID controller at each gas engine speed change rate by the output parameter of the turbocharger PID controller during steady-state operation of the gas engine to obtain the correction parameter of the turbocharger PID controller corresponding to each gas engine speed change rate.

[0100] In this embodiment, the test calibration for each gas engine speed change rate is performed according to the following steps: Based on the gas engine speed change rate, such as 80 r / s, the gas engine is started from idle speed (e.g., 600 rpm at 0 load) and gradually increased to full load at several preset gas engine speeds, such as 1000 rpm, 1200 rpm, 1400 rpm, 1600 rpm, and 1800 rpm, until the turbocharger speed reaches a preset overspeed threshold. The speeds at 1000 rpm, 1200 rpm, 1400 rpm, and 1600 rpm are recorded. The output parameters of the turbocharger PID controller at full load (1000 rpm, 1200 rpm, 1400 rpm, 1600 rpm, and 1800 rpm) are taken as the minimum value. This minimum value is then used as the output parameter of the turbocharger PID controller at a speed change rate of 80 rpm. This value is then divided by the output parameter of the turbocharger PID controller during steady-state operation (e.g., a speed change rate of less than 50 rpm). This gives the corrected parameters of the turbocharger PID controller at a speed change rate of 80 rpm.

[0101] Secondly, embodiments of this application also provide a turbocharger overspeed protection device.

[0102] In one embodiment, reference is made to Figure 4 , Figure 4 This is a functional module diagram of an embodiment of the turbocharger overspeed protection device of this application, as shown below. Figure 4 As shown, the turbocharger overspeed protection device includes:

[0103] The first determining module 10 is used to determine the maximum duty cycle of the turbocharger exhaust bypass solenoid valve based on the gas engine speed, atmospheric pressure and the first calibration relationship table when turbocharger boost is detected.

[0104] The second determining module 20 is used to determine the speed change rate correction parameter for the maximum duty cycle based on the gas engine speed change rate and the second calibration relationship table.

[0105] The third determining module 30 is used to determine the intake temperature correction parameter for the maximum duty cycle based on the gas engine speed, intake temperature and the third calibration relationship table;

[0106] The correction module 40 is used to correct the maximum duty cycle using the speed change rate correction parameter and the intake air temperature correction parameter to obtain the correction value of the maximum duty cycle.

[0107] The first control module 50 is used to control the duty cycle of the turbocharger exhaust bypass solenoid valve to the correction value of the maximum duty cycle if the duty cycle of the turbocharger exhaust bypass solenoid valve is greater than the correction value of the maximum duty cycle, so as to limit the speed of the turbocharger.

[0108] Furthermore, in one embodiment, the turbocharger overspeed protection device further includes a second control module, used for:

[0109] When turbocharger boost is detected, the correction parameters of the turbocharger PID controller are determined based on the gas engine speed change rate and the fourth calibration relationship table.

[0110] The current output parameters of the turbocharger PID controller are corrected using the correction parameters of the turbocharger PID controller to obtain the basic duty cycle of the turbocharger exhaust bypass solenoid valve. The current output parameters of the turbocharger PID controller are determined based on the gas engine speed, pressure difference, and the fifth calibration relationship table. The fifth calibration relationship table includes the correspondence between different gas engine speeds, pressure differences, and the current output parameters of the turbocharger PID controller. The pressure difference is the difference between the actual boost pressure and the target boost pressure.

[0111] The duty cycle of the turbocharger exhaust bypass solenoid valve is controlled by the smaller of the base duty cycle and the maximum duty cycle correction value, in order to limit the turbocharger speed.

[0112] Further, in one embodiment, the first calibration relationship table includes the correspondence between different gas engine speeds, atmospheric pressures, and the maximum duty cycle of the turbocharger exhaust bypass solenoid valve. The steps for determining the first calibration relationship table include:

[0113] For each combination of gas engine speed and atmospheric pressure, the load on the gas engine is increased to full load;

[0114] The duty cycle of the exhaust bypass solenoid valve when the turbocharger speed reaches the preset overspeed threshold is taken as the maximum duty cycle of the turbocharger exhaust bypass solenoid valve corresponding to each combination of gas engine speed and atmospheric pressure.

[0115] Further, in one embodiment, the second calibration relationship table includes the correspondence between different gas engine speed change rates and the speed change rate correction parameter for maximum duty cycle, and the steps for determining the second calibration relationship table include:

[0116] Under standard atmospheric pressure, for each gas engine speed change rate, the gas engine is pulled up from idle condition to full load at multiple preset gas engine speeds according to the gas engine speed change rate. The duty cycle of the exhaust bypass solenoid valve when the turbocharger speed reaches the preset overspeed threshold is taken as the maximum duty cycle of the exhaust bypass solenoid valve at each preset gas engine speed.

[0117] The minimum value of the maximum duty cycle of the exhaust bypass solenoid valve at each preset gas engine speed is taken as the maximum duty cycle of the exhaust bypass solenoid valve at each gas engine speed change rate.

[0118] Divide the maximum duty cycle of the exhaust bypass solenoid valve under each gas engine speed change rate by the maximum duty cycle during steady-state operation of the gas engine to obtain the speed change rate correction parameter corresponding to the maximum duty cycle of each gas engine speed change rate.

[0119] Further, in one embodiment, the third calibration relationship table includes the correspondence between different gas engine speeds, intake air temperatures, and intake air temperature correction parameters for maximum duty cycles. The steps for determining the third calibration relationship table include:

[0120] Under standard atmospheric pressure, for each combination of gas engine speed and intake air temperature, the load of the gas engine is increased to full load;

[0121] The duty cycle of the exhaust bypass solenoid valve when the turbocharger speed reaches the preset overspeed threshold is taken as the maximum duty cycle of the turbocharger exhaust bypass solenoid valve for each combination of gas engine speed and intake air temperature.

[0122] Divide the maximum duty cycle of the turbocharger exhaust bypass solenoid valve for each combination of gas engine speed and intake air temperature by the maximum duty cycle of the turbocharger exhaust bypass solenoid valve for the same combination of gas engine speed and preset reference intake air temperature to obtain the intake air temperature correction parameter corresponding to the maximum duty cycle of each combination of gas engine speed and intake air temperature.

[0123] Furthermore, in one embodiment, the fourth calibration relationship table includes the correspondence between different gas engine speed change rates and the correction parameters of the turbocharger PID controller, and the steps for determining the fourth calibration relationship table include:

[0124] For each gas engine speed change rate, the gas engine is increased from idle to full load at multiple preset gas engine speeds according to the gas engine speed change rate. The output parameters of the turbocharger PID controller when the turbocharger speed reaches the preset overspeed threshold are used as the output parameters of the turbocharger PID controller at each preset gas engine speed.

[0125] The minimum value among the output parameters of the turbocharger PID controller at each preset gas engine speed is used as the output parameter of the turbocharger PID controller at each gas engine speed change rate.

[0126] Divide the output parameter of the turbocharger PID controller at each gas engine speed change rate by the output parameter of the turbocharger PID controller during steady-state operation of the gas engine to obtain the correction parameter of the turbocharger PID controller corresponding to each gas engine speed change rate.

[0127] The functions of each module in the above-mentioned turbocharger overspeed protection device correspond to the steps in the above-mentioned turbocharger overspeed protection method embodiment, and their functions and implementation processes will not be described in detail here.

[0128] Thirdly, embodiments of this application provide a turbocharger overspeed protection device.

[0129] Reference Figure 5 , Figure 5 This is a schematic diagram of the hardware structure of the turbocharger overspeed protection device involved in the embodiments of this application. In this embodiment, the turbocharger overspeed protection device may include a processor, a memory, a communication interface, and a communication bus.

[0130] The communication bus can be of any type and is used to interconnect the processor, memory, and communication interface.

[0131] The communication interface includes input / output (I / O) interfaces, physical interfaces, and logical interfaces used for interconnecting components within the turbocharger overspeed protection device, as well as interfaces used for interconnecting the turbocharger overspeed protection device with other devices (such as other computing devices or user equipment). Physical interfaces can be Ethernet interfaces, fiber optic interfaces, ATM interfaces, etc.; user equipment can be displays, keyboards, etc.

[0132] Memory can be various types of storage media, such as random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), flash memory, optical storage, hard disk, programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), etc.

[0133] The processor can be a general-purpose processor, which can call the turbocharger overspeed protection program stored in memory and execute the turbocharger overspeed protection method provided in the embodiments of this application. For example, the general-purpose processor can be a central processing unit (CPU). The method executed when the turbocharger overspeed protection program is called can be referred to in the various embodiments of the turbocharger overspeed protection method of this application, and will not be repeated here.

[0134] Those skilled in the art will understand that Figure 5The hardware structure shown does not constitute a limitation of this application and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0135] Fourthly, embodiments of this application also provide a readable storage medium.

[0136] The present application has a readable storage medium storing a turbocharger overspeed protection program, wherein when the turbocharger overspeed protection program is executed by a processor, it implements the steps of the turbocharger overspeed protection method as described above.

[0137] The method implemented when the turbocharger overspeed protection procedure is executed can be referred to in various embodiments of the turbocharger overspeed protection method of this application, and will not be repeated here.

[0138] It should be noted that the sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0139] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes several instructions to cause a terminal device to execute the methods described in the various embodiments of this application.

[0140] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A method for overspeed protection of a turbocharger, characterized in that, The overspeed protection method for the turbocharger includes: When turbocharger boost is detected, the maximum duty cycle of the turbocharger exhaust bypass solenoid valve is determined based on the gas engine speed, atmospheric pressure, and the first calibration relationship table. Based on the gas engine speed change rate and the second calibration relationship table, determine the speed change rate correction parameter for the maximum duty cycle; Based on the gas engine speed, intake air temperature, and the third calibration relationship table, determine the intake air temperature correction parameter for the maximum duty cycle; The maximum duty cycle is corrected using the speed change rate correction parameter and the intake air temperature correction parameter to obtain the corrected value of the maximum duty cycle. If the duty cycle of the turbocharger exhaust bypass solenoid valve is greater than the correction value of the maximum duty cycle, then the duty cycle of the turbocharger exhaust bypass solenoid valve is controlled to the correction value of the maximum duty cycle in order to limit the speed of the turbocharger.

2. The turbocharger overspeed protection method as described in claim 1, characterized in that, The overspeed protection method for the turbocharger also includes: When turbocharger boost is detected, the correction parameters of the turbocharger PID controller are determined based on the gas engine speed change rate and the fourth calibration relationship table. The current output parameters of the turbocharger PID controller are corrected using the correction parameters of the turbocharger PID controller to obtain the basic duty cycle of the turbocharger exhaust bypass solenoid valve. The current output parameters of the turbocharger PID controller are determined based on the gas engine speed, pressure difference, and the fifth calibration relationship table. The fifth calibration relationship table includes the correspondence between different gas engine speeds, pressure differences, and the current output parameters of the turbocharger PID controller. The pressure difference is the difference between the actual boost pressure and the target boost pressure. The duty cycle of the turbocharger exhaust bypass solenoid valve is controlled by the smaller of the base duty cycle and the maximum duty cycle correction value, in order to limit the turbocharger speed.

3. The turbocharger overspeed protection method as described in claim 1, characterized in that, The first calibration relationship table includes the correspondence between different gas engine speeds, atmospheric pressures, and the maximum duty cycle of the turbocharger exhaust bypass solenoid valve. The steps for determining the first calibration relationship table include: For each combination of gas engine speed and atmospheric pressure, the load on the gas engine is increased to full load; The duty cycle of the exhaust bypass solenoid valve when the turbocharger speed reaches the preset overspeed threshold is taken as the maximum duty cycle of the turbocharger exhaust bypass solenoid valve corresponding to each combination of gas engine speed and atmospheric pressure.

4. The turbocharger overspeed protection method as described in claim 1, characterized in that, The second calibration relationship table includes the correspondence between different gas engine speed change rates and the speed change rate correction parameters for maximum duty cycle. The steps for determining the second calibration relationship table include: Under standard atmospheric pressure, for each gas engine speed change rate, the gas engine is pulled up from idle condition to full load at multiple preset gas engine speeds according to the gas engine speed change rate. The duty cycle of the exhaust bypass solenoid valve when the turbocharger speed reaches the preset overspeed threshold is taken as the maximum duty cycle of the exhaust bypass solenoid valve at each preset gas engine speed. The minimum value of the maximum duty cycle of the exhaust bypass solenoid valve at each preset gas engine speed is taken as the maximum duty cycle of the exhaust bypass solenoid valve at each gas engine speed change rate. Divide the maximum duty cycle of the exhaust bypass solenoid valve under each gas engine speed change rate by the maximum duty cycle during steady-state operation of the gas engine to obtain the speed change rate correction parameter corresponding to the maximum duty cycle of each gas engine speed change rate.

5. The turbocharger overspeed protection method as described in claim 1, characterized in that, The third calibration relationship table includes the correspondence between different gas engine speeds, intake air temperatures, and intake air temperature correction parameters for maximum duty cycles. The steps for determining the third calibration relationship table include: Under standard atmospheric pressure, for each combination of gas engine speed and intake air temperature, the load of the gas engine is increased to full load; The duty cycle of the exhaust bypass solenoid valve when the turbocharger speed reaches the preset overspeed threshold is taken as the maximum duty cycle of the turbocharger exhaust bypass solenoid valve for each combination of gas engine speed and intake air temperature. Divide the maximum duty cycle of the turbocharger exhaust bypass solenoid valve for each combination of gas engine speed and intake air temperature by the maximum duty cycle of the turbocharger exhaust bypass solenoid valve for the same combination of gas engine speed and preset reference intake air temperature to obtain the intake air temperature correction parameter corresponding to the maximum duty cycle of each combination of gas engine speed and intake air temperature.

6. The turbocharger overspeed protection method as described in claim 2, characterized in that, The fourth calibration relationship table includes the correspondence between different gas engine speed change rates and the correction parameters of the turbocharger PID controller. The steps for determining the fourth calibration relationship table include: For each gas engine speed change rate, the gas engine is increased from idle to full load at multiple preset gas engine speeds according to the gas engine speed change rate. The output parameters of the turbocharger PID controller when the turbocharger speed reaches the preset overspeed threshold are used as the output parameters of the turbocharger PID controller at each preset gas engine speed. The minimum value among the output parameters of the turbocharger PID controller at each preset gas engine speed is used as the output parameter of the turbocharger PID controller at each gas engine speed change rate. Divide the output parameter of the turbocharger PID controller at each gas engine speed change rate by the output parameter of the turbocharger PID controller during steady-state operation of the gas engine to obtain the correction parameter of the turbocharger PID controller corresponding to each gas engine speed change rate.

7. A turbocharger overspeed protection device, characterized in that, The turbocharger overspeed protection device includes: The first determining module is used to determine the maximum duty cycle of the turbocharger exhaust bypass solenoid valve based on the gas engine speed, atmospheric pressure and the first calibration relationship table when turbocharger boost is detected. The second determining module is used to determine the speed change rate correction parameter for the maximum duty cycle based on the gas engine speed change rate and the second calibration relationship table. The third determination module is used to determine the intake temperature correction parameter for the maximum duty cycle based on the gas engine speed, intake temperature and the third calibration relationship table; The correction module is used to correct the maximum duty cycle using the speed change rate correction parameter and the intake air temperature correction parameter to obtain the corrected value of the maximum duty cycle. The first control module is used to control the duty cycle of the turbocharger exhaust bypass solenoid valve to the correction value of the maximum duty cycle if the duty cycle of the turbocharger exhaust bypass solenoid valve is greater than the correction value of the maximum duty cycle, so as to limit the speed of the turbocharger.

8. The turbocharger overspeed protection device as described in claim 7, characterized in that, The turbocharger overspeed protection device also includes a second control module for: When turbocharger boost is detected, the correction parameters of the turbocharger PID controller are determined based on the gas engine speed change rate and the fourth calibration relationship table. The current output parameters of the turbocharger PID controller are corrected using the correction parameters of the turbocharger PID controller to obtain the basic duty cycle of the turbocharger exhaust bypass solenoid valve. The current output parameters of the turbocharger PID controller are determined based on the gas engine speed, pressure difference, and the fifth calibration relationship table. The fifth calibration relationship table includes the correspondence between different gas engine speeds, pressure differences, and the current output parameters of the turbocharger PID controller. The pressure difference is the difference between the actual boost pressure and the target boost pressure. The duty cycle of the turbocharger exhaust bypass solenoid valve is controlled by the smaller of the base duty cycle and the maximum duty cycle correction value, in order to limit the turbocharger speed.

9. A turbocharger overspeed protection device, characterized in that, The turbocharger overspeed protection device includes a processor, a memory, and a turbocharger overspeed protection program stored in the memory and executable by the processor, wherein when the turbocharger overspeed protection program is executed by the processor, it implements the steps of the turbocharger overspeed protection method as described in any one of claims 1 to 6.

10. A readable storage medium, characterized in that, The readable storage medium stores a turbocharger overspeed protection program, wherein when the turbocharger overspeed protection program is executed by a processor, it implements the steps of the turbocharger overspeed protection method as described in any one of claims 1 to 6.

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