Smoking control system and method for explosion-proof diesel engine

Abstract

The invention relates to an explosion-proof diesel engine smoking control system and method, and the system comprises a data collection unit which is used for collecting the rotating speed data, the air inlet supercharging pressure data, the cooling water temperature data, the air inlet temperature data and the atmospheric pressure data of an explosion-proof diesel engine; the data processing unit is used for calculating air inlet flow data, stroke air inlet quantity and an air-fuel ratio limit value of the explosion-proof diesel engine according to the rotating speed data, the air inlet supercharging pressure data and the air inlet temperature data; according to the rotating speed data, the stroke air inflow and the air-fuel ratio limit value, the smoke limiting oil amount is calculated; the fuel injection pulse width of the explosion-proof diesel engine is calculated according to the smoke limiting fuel quantity; the oil injection control unit is used for outputting a valve control signal according to the oil injection pulse width; the oil injection control valve is used for changing the on-off state of the oil injection control valve under the control of the valve control signal so as to control the oil injection quantity of the explosion-proof diesel engine; the anti-explosion diesel engine can effectively prevent the anti-explosion diesel engine from smoking.

Description

Technical Field

[0001] The invention relates to the technical field of explosion-proof diesel engines, and in particular to a smoke control system and method for an explosion-proof diesel engine. Background Art

[0002] Explosion-proof diesel engines have become the core power source of auxiliary transportation equipment in coal mines due to their excellent power performance and excellent mobility. With the continuous expansion of coal mine construction, the application scope of explosion-proof diesel engines is becoming increasingly wide. However, the ventilation conditions in coal mines are often poor. Once the emission of explosion-proof diesel engines is abnormal, it will seriously threaten the physical and mental health of underground workers.

[0003] Under certain operating conditions, such as rapid acceleration of the diesel engine, low atmospheric pressure, blockage of the intake system, etc., the diesel engine may experience insufficient air intake. At this time, due to excessive fuel injection, the combustion efficiency will decrease, the emission condition will deteriorate, and smoke will occur. Summary of the invention

[0004] In order to solve the technical problems in the prior art that excessive fuel injection of an explosion-proof diesel engine leads to decreased combustion efficiency, worsened emission conditions, and the occurrence of smoke, the present invention provides an explosion-proof diesel engine smoke control system and method.

[0005] The technical solution of the present invention to solve the above technical problems is as follows:

[0006] A smoke control system for explosion-proof diesel engines, used to prevent abnormal smoke from occurring in explosion-proof diesel engines, comprising:

[0007] A data acquisition unit is used to collect speed data, intake boost pressure data, cooling water temperature data, intake air temperature data and atmospheric pressure data of the explosion-proof diesel engine;

[0008] A data processing unit, used for calculating the intake flow data of the explosion-proof diesel engine according to the speed data, the intake boost pressure data and the intake temperature data; calculating the stroke intake volume according to the intake flow data, the speed data, the number of cylinders of the explosion-proof diesel engine and the number of strokes of the explosion-proof diesel engine; wherein the stroke intake volume is the intake flow of the cylinder of the explosion-proof diesel engine in one stroke; calculating the air-fuel ratio limit according to the intake boost pressure data, the intake temperature data, the speed data, the cooling water temperature data and the atmospheric pressure data; calculating the smoke limit oil quantity according to the speed data, the stroke intake volume and the air-fuel ratio limit; calculating the injection pulse width of the explosion-proof diesel engine according to the smoke limit oil quantity;

[0009] An injection control unit, used for outputting a valve control signal according to the injection pulse width;

[0010] The fuel injection control valve is used to change its on / off state under the control of the valve control signal, thereby controlling the fuel injection amount of the explosion-proof diesel engine.

[0011] The beneficial effects of the present invention are as follows: by collecting the speed data, intake boost pressure data, cooling water temperature data, intake temperature data and atmospheric pressure data of the explosion-proof diesel engine to calculate the smoke limit oil quantity, and by controlling the injection control valve through the smoke limit oil quantity, the injection limit quantity is precisely controlled when the explosion-proof diesel engine has excessive injection amount, thereby effectively preventing the explosion-proof diesel engine from smoking.

[0012] Based on the above technical solution, the present invention can also be improved as follows.

[0013] Further, the data processing unit is specifically used to construct an air flow table and an intake air temperature correction table; wherein the air flow table is a two-dimensional table, the rows of the air flow table represent the speed data, the columns of the air flow table represent the intake air boost pressure data, and the fields of the air flow table represent the intake air flow basic data; the intake air temperature correction table is a one-dimensional table, the rows of the intake air temperature correction table represent the intake air temperature data, and the fields of the intake air temperature correction table represent the temperature correction coefficient;

[0014] The data processing unit is also specifically used to query the air flow table according to the speed data and the intake boost pressure data to obtain the basic intake flow data corresponding to the speed data and the intake boost pressure data; query the intake temperature correction table according to the intake temperature data to obtain the temperature correction coefficient corresponding to the intake temperature data; calculate the intake flow data according to the intake flow basic data and the temperature correction coefficient.

[0015] Furthermore, the data processing unit is also specifically used to preset a plurality of different speed data and a plurality of different intake boost pressure data;

[0016] The data acquisition unit is specifically used to respectively acquire the theoretical air intake volume of the explosion-proof diesel engine under a plurality of different speed data, and obtain a plurality of corresponding theoretical air intake volumes;

[0017] The data processing unit is further specifically used to calculate the charging efficiency corresponding to each speed data by using each speed data and the corresponding theoretical intake volume, and obtain a plurality of corresponding charging efficiencies;

[0018] The data acquisition unit is also specifically used to collect the intake air temperature of the explosion-proof diesel engine under any of the speed data and any of the intake air boost pressure data, and correspondingly obtain a plurality of intake air temperature data;

[0019] The data processing unit is also specifically used to calculate the intake air density using any of the speed data, any of the intake boost pressure data and the corresponding intake temperature data, and obtain a plurality of corresponding air density data; calculate the intake flow of the explosion-proof diesel engine under any combination of the speed data and any of the intake boost pressure data according to any of the speed data, the corresponding charging efficiency, the corresponding air density data and the displacement of the explosion-proof diesel engine, and obtain a plurality of the intake flow basic data.

[0020] Furthermore, the data acquisition unit is also specifically used to use the gas flow meter to collect the intake flow of the explosion-proof diesel engine under the speed data condition corresponding to each intake temperature data, and obtain a plurality of actual intake flow data accordingly;

[0021] The data processing unit is further specifically used to calculate the temperature correction coefficient corresponding to each intake air temperature data according to the intake air flow basic data corresponding to each intake air temperature data and the actual intake air flow data.

[0022] Furthermore, the data processing unit is also specifically used to obtain the product of the intake air flow rate basic data and the temperature correction coefficient to obtain the intake air flow rate data.

[0023] Furthermore, the data processing unit is also specifically used to calculate the product of the intake flow data and the number of strokes of the explosion-proof diesel engine to obtain a first product value; calculate the product of the speed data and the number of cylinders of the explosion-proof diesel engine to obtain a second product value; multiply the second product value by 2 to obtain a third product value; and calculate the quotient of the first product value divided by the third product value to obtain the stroke intake volume.

[0024] The data processing unit is also specifically used to construct an air-fuel ratio limit basic mapping table, a water temperature correction offset table, a water temperature correction coefficient mapping table, an atmospheric pressure correction offset mapping table and an atmospheric pressure correction coefficient mapping table; wherein the air-fuel ratio limit basic mapping table, the water temperature correction offset table, the atmospheric pressure correction offset mapping table and the atmospheric pressure correction coefficient mapping table are all two-dimensional tables, and the water temperature correction coefficient mapping table is a one-dimensional table; the rows of the air-fuel ratio limit basic mapping table represent the speed data, the columns of the air-fuel ratio limit basic mapping table represent the intake boost pressure data, and the fields of the air-fuel ratio limit basic mapping table represent the air-fuel ratio limit basic value; the rows of the water temperature correction offset table represent the speed data, the water temperature correction offset table represents the intake boost pressure data, and the fields of the air-fuel ratio limit basic mapping table represent the air-fuel ratio limit basic value. The columns of the offset table represent the intake boost pressure data, and the domain of the water temperature correction offset table represents the water temperature correction offset value; the rows of the water temperature correction coefficient mapping table represent the cooling water temperature data, and the domain of the water temperature correction coefficient mapping table represents the water temperature correction coefficient; the rows of the atmospheric pressure correction offset mapping table represent the speed data, the columns of the atmospheric pressure correction offset mapping table represent the intake boost pressure data, and the domain of the atmospheric pressure correction offset mapping table represents the atmospheric pressure correction offset value; the rows of the atmospheric pressure correction coefficient mapping table represent the cooling water temperature data, the columns of the atmospheric pressure correction coefficient mapping table represent the intake boost pressure data, and the domain of the atmospheric pressure correction coefficient mapping table represents the atmospheric pressure correction coefficient;

[0025] The data processing unit is further specifically used to query the air-fuel ratio limit base value under the combination of the speed data and the intake boost pressure data in the air-fuel ratio limit base mapping table; query the water temperature correction offset value under the combination of the speed data and the intake boost pressure data in the water temperature correction offset table; query the water temperature correction coefficient corresponding to the cooling water temperature data in the water temperature correction coefficient mapping table; query the atmospheric pressure correction offset value under the combination of the speed data and the intake boost pressure data in the atmospheric pressure correction offset mapping table; query the atmospheric pressure correction coefficient under the combination of the cooling water temperature data and the intake boost pressure data in the atmospheric pressure correction coefficient mapping table;

[0026] The data processing unit is further specifically configured to calculate the air-fuel ratio limit value by using the air-fuel ratio limit value base value, the water temperature correction offset value, the water temperature correction coefficient, the atmospheric pressure correction offset value, and the atmospheric pressure correction coefficient.

[0027] Furthermore, the data processing unit is also specifically used to calculate the quotient of the stroke intake volume and the air-fuel ratio limit value to obtain the smoke limit oil volume.

[0028] Further, the data processing unit is also specifically used to construct an oil quantity to pulse width mapping table; wherein the oil quantity to pulse width mapping table is a two-dimensional table, the rows of the oil quantity to pulse width mapping table represent the speed data, the columns of the oil quantity to pulse width mapping table represent the smoke limit oil quantity, and the domain of the oil quantity to pulse width mapping table represents the injection pulse width;

[0029] The data processing unit is also specifically used to query the injection pulse width under the combination of the smoke limit oil quantity and the speed data in the oil quantity to pulse width mapping table.

[0030] In order to solve the above technical solution, the present invention also provides a method for controlling smoke emission of an explosion-proof diesel engine, and its specific technical solution is as follows:

[0031] A method for controlling smoke from an explosion-proof diesel engine, applied to the above-mentioned smoke control system for an explosion-proof diesel engine, comprises the following steps:

[0032] The data acquisition unit is used to collect the speed data, intake boost pressure data, cooling water temperature data, gear position data, intake temperature data and atmospheric pressure data of the explosion-proof diesel engine;

[0033] Calculating the intake flow data of the explosion-proof diesel engine according to the rotation speed data, the intake boost pressure data and the intake temperature data using a data processing unit;

[0034] Calculating the stroke intake volume by using a data processing unit according to the intake flow data, the speed data, the number of cylinders of the explosion-proof diesel engine and the number of strokes of the explosion-proof diesel engine; wherein the stroke intake volume is the intake flow of the cylinder of the explosion-proof diesel engine in one stroke;

[0035] Calculating an air-fuel ratio limit value using a data processing unit according to the intake boost pressure data, the intake temperature data, the speed data, the cooling water temperature data, and the atmospheric pressure data;

[0036] Calculating the smoke limit oil quantity according to the speed data, the stroke air intake volume and the air-fuel ratio limit value by using a data processing unit; calculating the injection pulse width of the explosion-proof diesel engine according to the smoke limit oil quantity;

[0037] outputting a valve control signal according to the injection pulse width using an injection control unit;

[0038] The fuel injection control valve is used to change its on / off state under the control of the valve control signal, thereby controlling the fuel injection amount of the explosion-proof diesel engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a structural block diagram of an explosion-proof diesel engine smoke control system in an embodiment of the present invention;

[0040] Figure 2 A flowchart of calculating the intake flow data of the explosion-proof diesel engine in an embodiment of the present invention;

[0041] Figure 3 The figure is a flowchart of calculating the air-fuel ratio limit value in an embodiment of the present invention. DETAILED DESCRIPTION

[0042] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0043] like Figure 1 As shown, this embodiment provides an explosion-proof diesel engine smoke control system, which is used to prevent the explosion-proof diesel engine from abnormally emitting smoke, including:

[0044] The data acquisition unit is used to collect the speed data, intake boost pressure data, cooling water temperature data, intake temperature data and atmospheric pressure data of the explosion-proof diesel engine; wherein, the data acquisition unit includes a speed sensor, a boost pressure sensor, an atmospheric pressure sensor, a water temperature sensor and an intake temperature sensor; both the boost pressure sensor and the atmospheric pressure sensor are intrinsically safe pressure sensors; the boost pressure sensor adopts the model GPD1.0, and the atmospheric pressure sensor adopts the model GPD0.35; the water temperature sensor and the intake temperature sensor are both intrinsically safe temperature sensors. The intake temperature sensor is a WD150 temperature sensor, and the water temperature sensor is a GWD200 temperature sensor. The speed sensor is a mining intrinsically safe crankshaft (model GSH5000) or a cam speed sensor (model GSH2500).

[0045] The speed sensor is used to collect speed data; the boost pressure sensor is used to collect intake boost pressure data; the intake temperature sensor is used to collect intake temperature data; the atmospheric pressure sensor is used to collect atmospheric pressure data; and the water temperature sensor is used to collect cooling water temperature data.

[0046] A data processing unit is used to calculate the intake flow data of the explosion-proof diesel engine according to the speed data, the intake boost pressure data and the intake temperature data; calculate the stroke intake volume according to the intake flow data, the speed data, the number of cylinders of the explosion-proof diesel engine and the number of strokes of the explosion-proof diesel engine; wherein the stroke intake volume is the intake flow of the cylinder of the explosion-proof diesel engine in one stroke; calculate the air-fuel ratio limit according to the intake boost pressure data, the intake temperature data, the speed data, the cooling water temperature data and the atmospheric pressure data; calculate the smoke limit oil quantity according to the speed data, the stroke intake volume and the air-fuel ratio limit; calculate the injection pulse width of the explosion-proof diesel engine according to the smoke limit oil quantity; wherein the data processing unit also includes a memory and a calculator; wherein the memory is used to store the speed data, the intake boost pressure data, the cooling water temperature data, the intake temperature data and the atmospheric pressure data; the calculator is preferably an MCU or a vehicle ECU, etc.

[0047] An injection control unit, used for outputting a valve control signal according to the injection pulse width;

[0048] The fuel injection control valve is used to change its on / off state under the control of the valve control signal, thereby controlling the fuel injection amount of the explosion-proof diesel engine.

[0049] In some embodiments, the data processing unit is specifically used to construct an air flow table and an intake temperature correction table; wherein, the air flow table is a two-dimensional table, the rows of the air flow table represent the speed data, the columns of the air flow table represent the intake boost pressure data, and the field of the air flow table represents the intake flow basic data; the intake temperature correction table is a one-dimensional table, the rows of the intake temperature correction table represent the intake temperature data, and the field of the intake temperature correction table represents the temperature correction coefficient; wherein, the air flow table is shown in Table 1, and the intake temperature correction table is shown in Table 2.

[0050] Table 1 Air flow table

[0051]

[0052]

[0053] Table 2 Intake air temperature correction table

[0054] -20 -10 0 10 20 30 40 50 60 70 80 90 100 k 1.24 1.19 1.15 1.11 1.07 1.03 1 0.97 0.94 0.91 0.89 0.86 0.84

[0055] By collecting the speed and intake boost pressure, the initial value of the intake flow is obtained by querying Table 1. For example, if the current speed is 1000rpm and the boost pressure is 120kpa, the initial value of the intake flow is 120; if the current speed is 1150rpm, the boost pressure is 125kpa.

[0056] When the speed and intake boost pressure are not in Table 1, that is, when the corresponding speed data and intake boost pressure data are not found in Table 1, the basic intake flow data corresponding to the combination of speed data and intake boost pressure data is calculated by interpolation algorithm. The linear interpolation algorithm is as follows:

[0057] Step 1: According to the coordinates (Y1, M11), (Y2, M12), calculate the interpolation value MX1 based on the known intake boost pressure Y. Y1 and Y2 represent two values ​​adjacent to the intake boost pressure data in Table 1; M11 and M12 represent two values ​​adjacent to the speed data in Table 1.

[0058] MX1=(M12-M11)*(Y-Y1) / (Y2-Y1)+M11.

[0059] Step 2: Based on the coordinates (Y1, M21), (Y2, M22), calculate the interpolation MX1 based on the known boost pressure Y.

[0060] MX2=(M22-M21)*(Y-Y1) / (Y2-Y1)+M21.

[0061] Step 2: Based on the coordinates (X1, MX1), (X2, MX2), calculate the interpolation MY based on the known speed X.

[0062] MY=(MX2-MX1)*(X-X1) / (X2-X1)+MX1.

[0063] If we look up Table 1, we get: X1 is 1000, X2 is 1200, Y1 is 110, Y2 is 120; M11 is 120, M12 is 155, M21 is 150, M22 is 185;

[0064] MX1=(M12-M11)*(Y-Y1) / (Y2-Y1)+M11.

[0065] =(155-120)*(125-120) / (130-120)+120

[0066] =137.5;

[0067] MX2=(M22-M21)*(Y-Y1) / (Y2-Y1)+M21.

[0068] =(185-150)*(125-120) / (130-120)+150

[0069] =167.5;

[0070] MY=(MX2-MX1)*(X-X1) / (X2-X1)+MX1.

[0071] =(167.5-137.5)*(1150-1000) / (1200-1000)+137.5

[0072] =160;

[0073] That is: when the intake boost pressure data is 125, when the speed data is 1000, the basic data of the intake flow rate is 137.5; when the speed data is 1150, the basic data of the intake flow rate is 160; when the speed data is 1200, the basic data of the intake flow rate is 167.5.

[0074] Similarly, when the temperature correction coefficient corresponding to the intake air temperature data cannot be directly queried in Table 2, the interpolation algorithm is also used to calculate the corresponding temperature correction coefficient.

[0075] In some embodiments, Figure 2 As shown, the method for calculating the stroke intake volume according to the intake flow data, the speed data, the number of cylinders of the explosion-proof diesel engine and the number of strokes of the explosion-proof diesel engine is as follows:

[0076] The data processing unit queries the air flow table according to the speed data and the intake boost pressure data to obtain the basic intake flow data corresponding to the speed data and the intake boost pressure data; queries the intake temperature correction table according to the intake temperature data to obtain the temperature correction coefficient corresponding to the intake temperature data; and calculates the intake flow data according to the intake flow basic data and the temperature correction coefficient.

[0077] The data processing unit presets a plurality of different speed data and a plurality of different intake boost pressure data; the data acquisition unit is specifically used to respectively acquire the theoretical intake volume of the explosion-proof diesel engine under a plurality of different speed data, and obtain a plurality of corresponding theoretical intake volumes;

[0078] The data processing unit calculates the charging efficiency corresponding to each speed data by using each speed data and the corresponding theoretical intake air volume, and obtains a plurality of corresponding charging efficiencies;

[0079] The data acquisition unit acquires the intake air temperature of the explosion-proof diesel engine under any of the speed data and any of the intake air boost pressure data, and correspondingly obtains a plurality of intake air temperature data;

[0080] The data processing unit calculates the intake air density using any of the speed data, any of the intake boost pressure data and the corresponding intake temperature data, and obtains a plurality of corresponding air density data; calculates the intake flow of the explosion-proof diesel engine under any combination of the speed data and any of the intake boost pressure data according to any of the speed data, the corresponding charging efficiency, the corresponding air density data and the displacement of the explosion-proof diesel engine, and obtains a plurality of basic intake flow data.

[0081] The data acquisition unit also specifically uses the gas flow meter to collect the intake flow of the explosion-proof diesel engine under the speed data condition corresponding to each intake temperature data, and obtains a plurality of actual intake flow data accordingly;

[0082] The data processing unit calculates the temperature correction coefficient corresponding to each of the intake air temperature data according to the intake air flow basic data corresponding to each of the intake air temperature data and the actual intake air flow data.

[0083] The data processing unit calculates the product of the intake air flow basic data and the temperature correction coefficient to obtain the intake air flow data.

[0084] The steps to construct the air flow table and intake air temperature correction table are as follows:

[0085] The data of the intake flow meter is obtained through bench tests of diesel engines and formula calculations.

[0086] Step 1: Bench test. Use a gas flow meter to test the actual air flow (Ma) at each speed point.

[0087] Step 2: Calculate parameters.

[0088] Given the engine parameters (theoretical air intake volume Ms of the engine), the charging efficiency η = Ma / Ms at each speed point of the engine is calculated.

[0089] The air density ρ (kg / m3) and air flow W (kg / h) under the current conditions are calculated through the collected data: EngineSpeed ​​(rpm), boost pressure BoostPress (kpa), and intake air temperature InletAirTemp (℃).

[0090] ρ=(BoostPress*1000) / (287.1*(273+InletAirTemp)).

[0091] Combined with the engine's own parameters and engine displacement V (L), calculate the intake flow rate:

[0092] W=η*ρ*EngineSpeed*V*30 / 1000;

[0093] Improve the intake flow meter.

[0094] The calculated intake air flow rate and the actual air flow rate are used to calculate the intake air temperature correction table.

[0095] In some embodiments, the data processing unit is also specifically used to calculate the product of the intake flow data and the number of strokes of the explosion-proof diesel engine to obtain a first product value; calculate the product of the speed data and the number of cylinders of the explosion-proof diesel engine to obtain a second product value; multiply the second product value by 2 to obtain a third product value; calculate the quotient of the first product value divided by the third product value to obtain the stroke intake volume.

[0096] The data processing unit is also specifically used to construct an air-fuel ratio limit basic mapping table, a water temperature correction offset table, a water temperature correction coefficient mapping table, an atmospheric pressure correction offset mapping table and an atmospheric pressure correction coefficient mapping table; wherein the air-fuel ratio limit basic mapping table, the water temperature correction offset table, the atmospheric pressure correction offset mapping table and the atmospheric pressure correction coefficient mapping table are all two-dimensional tables, and the water temperature correction coefficient mapping table is a one-dimensional table; the rows of the air-fuel ratio limit basic mapping table represent the speed data, the columns of the air-fuel ratio limit basic mapping table represent the intake boost pressure data, and the fields of the air-fuel ratio limit basic mapping table represent the air-fuel ratio limit basic value; the rows of the water temperature correction offset table represent the speed data, the water temperature correction offset table represents the intake boost pressure data, and the fields of the air-fuel ratio limit basic mapping table represent the air-fuel ratio limit basic value. The columns of the offset table represent the intake boost pressure data, and the fields of the water temperature correction offset table represent the water temperature correction offset values; the rows of the water temperature correction coefficient mapping table represent the cooling water temperature data, and the fields of the water temperature correction coefficient mapping table represent the water temperature correction coefficients; the rows of the atmospheric pressure correction offset mapping table represent the speed data, the columns of the atmospheric pressure correction offset mapping table represent the intake boost pressure data, and the fields of the atmospheric pressure correction offset mapping table represent the atmospheric pressure correction offset values; the rows of the atmospheric pressure correction coefficient mapping table represent the cooling water temperature data, the columns of the atmospheric pressure correction coefficient mapping table represent the intake boost pressure data, and the fields of the atmospheric pressure correction coefficient mapping table represent the atmospheric pressure correction coefficients.

[0097] The air-fuel ratio limit basic mapping table is shown in Table 3, the water temperature correction offset mapping table is shown in Table 4, the water temperature correction coefficient mapping table is shown in Table 5, the atmospheric pressure correction offset mapping table when the engine gear is in neutral is shown in Table 6, and the atmospheric pressure correction coefficient mapping table when the engine gear is in neutral is shown in Table 7.

[0098] The basic mapping table of air-fuel ratio limit is constructed as follows, which is obtained through bench testing. The process is as follows:

[0099] In the first step, the initial values ​​of the basic table of air-fuel ratio limits are all set to 23.

[0100] The second step is to remove the supercharger, put the diesel engine in a naturally aspirated condition, and connect a gas flow meter to test the intake flow. Connect the exhaust pipe to a smoke meter to test the smoke value FSN.

[0101] Step 3. Set the idle speed to 800rpm, gradually increase the throttle, and when the smoke value FSN is about 1.5, record the intake air flow AirFlow and fuel consumption Fuel, calculate the air-fuel ratio AirFuelRatio = AirFlow / Fuel, and fill in the mapping table. The current boost pressure is the atmospheric pressure.

[0102] Step 4: Set the speed to 1000 rpm and repeat step 3.

[0103] Step 5: Continue to increase the speed by 200 rpm until the maximum speed is reached and repeat step 3. From then on, the lower limit of the air-fuel ratio is obtained.

[0104] Step 6: Install the supercharger and conduct external characteristic test. Set the idle speed to 800rpm and the throttle to 100%, obtain the boost pressure and speed at this time, calculate the air-fuel ratio through the intake air flow and fuel consumption, and fill the value into the boost pressure and speed mapping position at this time.

[0105] Step 7: Continue to increase the speed by 200 rpm until the maximum speed is reached, and repeat step 6. From now on, the upper limit of the air-fuel ratio is obtained.

[0106] Step 8. After obtaining the upper and lower boundaries, perform linear interpolation in the middle to complete the entire table.

[0107] The ninth step is to verify the results through experiments again and fine-tune the data.

[0108] Table 3 Basic mapping table of air-fuel ratio limit

[0109]

[0110]

[0111] In Table 3, the rows are speed data, the columns are intake boost pressure data, and the values ​​in the table are air-fuel ratios.

[0112] Table 4 Water temperature correction offset mapping table

[0113] 800 900 1000 1200 1400 1600 1800 2000 2200 2400 10 0 0 0 0.1 0.2 0.3 0.42 0.45 0.56 0.56 20 0 0 0 0.1 0.3 0.3 0.42 0.45 0.56 0.56 30 0 0 0 0.1 0.3 0.3 0.42 0.45 0.56 0.56 40 0 0 0 0.1 0.3 0.3 0.45 0.45 0.56 0.56 50 0 0 0 0.1 0.3 0.3 0.45 0.45 0.56 0.56 60 0 0 0 0.1 0.3 0.3 0.45 0.45 0.56 0.56 70 0 0 0 0.1 0.3 0.3 0.45 0.45 0.56 0.56 80 0 0 0 0.1 0.3 0.3 0.46 0.46 0.56 0.56 90 0 0 0 0.2 0.3 0.3 0.47 0.47 0.56 0.56 100 0 0 0 0.2 0.3 0.3 0.48 0.48 0.56 0.56 110 0 0 0 0.2 0.3 0.3 0.48 0.48 0.56 0.56 120 0 0.1 0.2 0.2 0.3 0.3 0.48 0.48 0.56 0.56 130 0.1 0.2 0.2 0.2 0.3 0.3 0.48 0.48 0.56 0.56 140 0.2 0.2 0.2 0.2 0.3 0.3 0.48 0.48 0.56 0.56 150 0.2 0.2 0.2 0.2 0.3 0.3 0.48 0.48 0.56 0.56

[0114] In Table 4, the rows represent speed data, the columns represent intake boost pressure data, and the values ​​in the table are corrected offset values.

[0115] Table 5 Water temperature correction coefficient mapping table

[0116] -30 -20 -10 0 10 20 30 40 50 60 … K 1.5 1.4 1.3 1.2 1.4 1 1 1 1 0.9

[0117] In Table 5, the rows represent cooling water temperature data, and the values ​​in the table represent the water temperature correction coefficient K.

[0118] Table 6 Atmospheric pressure correction offset mapping table (neutral)

[0119]

[0120]

[0121] Table 7 Atmospheric pressure correction factor mapping table (neutral)

[0122] \ -20 -10 0 10 20 30 40 60 70 80 90 98 40 1.3 1.25 1.2 1.13 1.1 1.08 1.05 1.0 0.94 0.9 0.86 0.8 50 1.3 1.25 1.21 1.13 1.13 1.08 1.05 1.02 0.94 0.91 0.86 0.82 62 1.32 1.28 1.21 1.13 1.13 1.1 1.08 1.03 0.95 0.92 0.86 0.82 72 1.35 1.28 1.21 1.15 1.13 1.1 1.08 1.03 0.96 0.92 0.86 0.82 80 1.38 1.28 1.21 1.15 1.13 1.1 1.08 1.03 0.97 0.92 0.86 0.83 90 1.4 1.28 1.21 1.15 1.13 1.22 1.08 1.05 0.98 0.92 0.86 0.83 100 1.41 1.29 1.25 1.16 1.13 1.12 1.08 1.05 0.98 0.93 0.86 0.83 110 1.41 1.32 1.26 1.18 1.13 1.12 1.08 1.05 0.99 0.93 0.87 0.83 120 1.41 1.32 1.26 1.20 1.13 1.12 1.08 1.05 0.99 0.93 0.88 0.85 130 1.41 1.32 1.26 1.20 1.13 1.12 1.08 1.05 1.0 0.93 0.88 0.85 …

[0123] There are 7 atmospheric pressure correction offset mapping tables, namely the neutral atmospheric pressure correction coefficient table and the 1-6 gear neutral atmospheric pressure correction coefficient table; similarly, there are 7 tables of atmospheric pressure correction offset tables, namely the neutral atmospheric pressure correction offset table and the 1-6 gear neutral atmospheric pressure correction offset table.

[0124] In some embodiments, the data processing unit is further specifically used to query the air-fuel ratio limit base value under the combination of the speed data and the intake boost pressure data in the air-fuel ratio limit base mapping table; query the water temperature correction offset value under the combination of the speed data and the intake boost pressure data in the water temperature correction offset table; query the water temperature correction coefficient corresponding to the cooling water temperature data in the water temperature correction coefficient mapping table; query the atmospheric pressure correction offset value under the combination of the speed data and the intake boost pressure data in the atmospheric pressure correction offset mapping table; query the atmospheric pressure correction coefficient under the combination of the cooling water temperature data and the intake boost pressure data in the atmospheric pressure correction coefficient mapping table;

[0125] The data processing unit is further specifically configured to calculate the air-fuel ratio limit value by using the air-fuel ratio limit value base value, the water temperature correction offset value, the water temperature correction coefficient, the atmospheric pressure correction offset value, and the atmospheric pressure correction coefficient.

[0126] Specifically, the air-fuel ratio limit calculation formula is as follows:

[0127]

[0128] Among them, AFRO represents the air-fuel ratio limit basic value, KCW represents the water temperature correction coefficient, BCW represents the water temperature correction offset value, AFR1 represents the air-fuel ratio limit basic correction value, KIA represents the atmospheric pressure correction coefficient, BIA represents the atmospheric pressure correction offset value, and AFR represents the air-fuel ratio limit.

[0129] The data processing unit is also specifically used to calculate the quotient of the stroke intake volume and the air-fuel ratio limit value to obtain the smoke limit oil volume.

[0130] The data processing unit is also specifically used to construct an oil quantity to pulse width mapping table; wherein the oil quantity to pulse width mapping table is a two-dimensional table, the rows of the oil quantity to pulse width mapping table represent the speed data, the columns of the oil quantity to pulse width mapping table represent the smoke-limited oil quantity, and the domain of the oil quantity to pulse width mapping table represents the injection pulse width; specifically, the oil quantity to pulse width mapping table is as shown in Table 8.

[0131] The data processing unit is also specifically used to query the injection pulse width under the combination of the smoke limit oil quantity and the speed data in the oil quantity to pulse width mapping table.

[0132] Table 8 Oil volume to pulse width mapping table

[0133] 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200 2400 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5 25.63 25.63 20.63 15.63 12.09 5 0 0 0 0 0 0 0 0 0 0 8 30.96 30.96 28.96 23.96 17.96 12.88 6.5 0 0 0 0 0 0 0 0 0 10 35.2 35.2 33.2 31.2 26.2 19.95 14.91 7 0 0 0 0 0 0 0 0 15 40 40 40 40 37 32 24.67 17.34 7.5 0 0 0 0 0 0 0 20 45 45 45 45 45 42 37 25.93 16.86 8 0 0 0 0 0 0 25 50 50 50 50 50 49 43 35 25.25 15.5 8.5 0 0 0 0 0 30 55 55 55 55 55 55 50 45 35 25.75 17.5 9 0 0 0 0 35 60 60 60 60 60 60 57 54 46 36 26.59 20.19 9.5 0 0 0 40 65 65 65 65 65 65 65 62 55 47 37 27.86 20.72 10.29 0 0 45 70 70 70 70 70 70 70 70 64 56 48 38 29.63 21.52 12.24 0 50 75 75 75 75 75 75 75 75 75 70 60 51 42.63 33.73 25.3 14.65 55 80 80 80 80 80 80 80 80 80 79 75 67 59 48.2 39.67 27.01 60 85 85 85 85 85 85 85 85 85 85 84 79 72 64 56.23 47.47 65 90 90 90 90 90 90 90 90 90 90 90 87 81.5 76 69.5 62 …

[0134] The embodiment of the present invention calculates the smoke limit oil quantity by collecting the speed data, intake boost pressure data, cooling water temperature data, intake temperature data and atmospheric pressure data of the explosion-proof diesel engine, and controls the injection control valve by the smoke limit oil quantity to prevent the explosion-proof diesel engine from having excessive fuel injection by accurately controlling the injection limit quantity, thereby effectively preventing the explosion-proof diesel engine from smoking.

[0135] In some other embodiments, a method for controlling smoke emission from an explosion-proof diesel engine is also provided, and its specific technical solution is as follows:

[0136] A method for controlling smoke emission of an explosion-proof diesel engine, applied to the above-mentioned smoke emission control device of an explosion-proof diesel engine, comprises the following steps:

[0137] The data acquisition unit is used to collect the speed data, intake boost pressure data, cooling water temperature data, gear position data, intake temperature data and atmospheric pressure data of the explosion-proof diesel engine;

[0138] Calculating the intake flow data of the explosion-proof diesel engine according to the rotation speed data, the intake boost pressure data and the intake temperature data using a data processing unit;

[0139] Calculating the stroke intake volume by using a data processing unit according to the intake flow data, the speed data, the number of cylinders of the explosion-proof diesel engine and the number of strokes of the explosion-proof diesel engine; wherein the stroke intake volume is the intake flow of the cylinder of the explosion-proof diesel engine in one stroke;

[0140] Calculating an air-fuel ratio limit value using a data processing unit according to the intake boost pressure data, the intake temperature data, the speed data, the cooling water temperature data, and the atmospheric pressure data;

[0141] Calculating the smoke limit oil quantity according to the speed data, the stroke air intake volume and the air-fuel ratio limit value by using a data processing unit; calculating the injection pulse width of the explosion-proof diesel engine according to the smoke limit oil quantity;

[0142] outputting a valve control signal according to the injection pulse width using an injection control unit;

[0143] The fuel injection control valve is used to change its on / off state under the control of the valve control signal, thereby controlling the fuel injection amount of the explosion-proof diesel engine.

[0144] like Figure 2 As shown, the steps for calculating the intake flow data of the explosion-proof diesel engine are as follows:

[0145] Collect speed and boost pressure;

[0146] According to the speed and the boost pressure, the corresponding air flow basic value WO is obtained by querying the air flow table;

[0147] Collect intake air temperature;

[0148] According to the intake air temperature, the corresponding intake air temperature correction value K is obtained by querying the intake air temperature correction table;

[0149] Calculate the air flow rate under the current working condition: AirFlow = WO*K;

[0150] The stroke number CylinderStroke, the cylinder number CylinderNum and the air flow AirFlow are used to calculate the cylinder single stroke intake flow AirFlowCyl, i.e. the intake flow of the cylinder of the explosion-proof diesel engine in one stroke, under the current working condition:

[0151] AirFlowCyl=(AirFlow*CylinderStroke) / (EngineSpeed*CylinderNum*2).

[0152] like Figure 3 As shown, the steps of calculating the air-fuel ratio limit are as follows:

[0153] Collect speed, boost pressure, and cooling water temperature;

[0154] According to the speed and boost pressure, query the air-fuel ratio limit basic table to obtain the air-fuel ratio basic limit AFRO;

[0155] According to the cooling water temperature, query the water temperature correction coefficient table to obtain the water temperature correction coefficient KCW;

[0156] According to the speed and boost pressure, query the water temperature correction offset table to obtain the water temperature correction offset value BCW;

[0157] The air-fuel ratio basic limit correction value AFR1 is calculated using the air-fuel ratio basic limit value AFRO, the water temperature correction coefficient KCW and the water temperature correction offset value BCW: the calculation formula is: AFR1 = AFRO * KCW + BCW;

[0158] Gear information is collected, and the atmospheric pressure correction coefficient table is queried according to the gear information, cooling water temperature and atmospheric pressure to obtain the atmospheric pressure correction coefficient KIA; wherein different gears correspond to different gear information, and different gear information corresponds to different atmospheric pressure correction coefficient tables;

[0159] According to the gear information, speed and boost pressure, query the atmospheric pressure correction offset table to obtain the water temperature correction offset BIA;

[0160] The air-fuel ratio limit value AFR is calculated using the air-fuel ratio basic limit correction value AFR1, the atmospheric pressure correction coefficient KIA and the water temperature correction offset BIA; the calculation formula is: AFR=AFR1*KIA+BIA.

[0161] Among them, the speed represents the above-mentioned speed data, the boost pressure represents the above-mentioned intake boost pressure data, the air flow basic value WO represents the above-mentioned intake flow basic data; the intake temperature represents the above-mentioned intake temperature data, the atmospheric pressure represents the above-mentioned atmospheric pressure data, and the cooling water temperature represents the above-mentioned cooling water temperature data.

[0162] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the concept and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An explosion-proof diesel engine smoke control system, characterized in that: Used to prevent abnormal smoking in explosion-proof diesel engines, including: A data acquisition unit is used to collect speed data, intake boost pressure data, cooling water temperature data, intake air temperature data and atmospheric pressure data of the explosion-proof diesel engine; A data processing unit, used for calculating the intake flow data of the explosion-proof diesel engine according to the speed data, the intake boost pressure data and the intake temperature data; calculating the stroke intake volume according to the intake flow data, the speed data, the number of cylinders of the explosion-proof diesel engine and the number of strokes of the explosion-proof diesel engine; wherein the stroke intake volume is the intake flow of the cylinder of the explosion-proof diesel engine in one stroke; calculating the air-fuel ratio limit according to the intake boost pressure data, the intake temperature data, the speed data, the cooling water temperature data and the atmospheric pressure data; calculating the smoke limit oil quantity according to the speed data, the stroke intake volume and the air-fuel ratio limit; calculating the injection pulse width of the explosion-proof diesel engine according to the smoke limit oil quantity; An injection control unit, used for outputting a valve control signal according to the injection pulse width; The fuel injection control valve is used to change its on / off state under the control of the valve control signal, thereby controlling the fuel injection amount of the explosion-proof diesel engine.

2. The explosion-proof diesel engine smoke control system according to claim 1, characterized in that: The data processing unit is specifically used to construct an air flow table and an intake air temperature correction table; wherein the air flow table is a two-dimensional table, the rows of the air flow table represent the speed data, the columns of the air flow table represent the intake air boost pressure data, and the fields of the air flow table represent the intake air flow basic data; the intake air temperature correction table is a one-dimensional table, the rows of the intake air temperature correction table represent the intake air temperature data, and the fields of the intake air temperature correction table represent the temperature correction coefficient; The data processing unit is also specifically used to query the air flow table according to the speed data and the intake boost pressure data to obtain the basic intake flow data corresponding to the speed data and the intake boost pressure data; query the intake temperature correction table according to the intake temperature data to obtain the temperature correction coefficient corresponding to the intake temperature data; calculate the intake flow data according to the intake flow basic data and the temperature correction coefficient.

3. The explosion-proof diesel engine smoke control system according to claim 2 is characterized in that: The data processing unit is also specifically used to preset a plurality of different speed data and a plurality of different intake boost pressure data; The data acquisition unit is specifically used to respectively acquire the theoretical air intake volume of the explosion-proof diesel engine under a plurality of different speed data, and obtain a plurality of corresponding theoretical air intake volumes; The data processing unit is further specifically used to calculate the charging efficiency corresponding to each speed data by using each speed data and the corresponding theoretical intake volume, and obtain a plurality of corresponding charging efficiencies; The data acquisition unit is also specifically used to collect the intake air temperature of the explosion-proof diesel engine under any of the speed data and any of the intake air boost pressure data, and correspondingly obtain a plurality of intake air temperature data; The data processing unit is also specifically used to calculate the intake air density using any of the speed data, any of the intake boost pressure data and the corresponding intake temperature data, and obtain a plurality of corresponding air density data; calculate the intake flow of the explosion-proof diesel engine under any combination of the speed data and any of the intake boost pressure data according to any of the speed data, the corresponding charging efficiency, the corresponding air density data and the displacement of the explosion-proof diesel engine, and obtain a plurality of the intake flow basic data.

4. The explosion-proof diesel engine smoke control system according to claim 3 is characterized in that: The data acquisition unit is also specifically used to use the gas flow meter to collect the intake flow of the explosion-proof diesel engine under the speed data condition corresponding to each intake temperature data, and obtain a plurality of actual intake flow data accordingly; The data processing unit is further specifically used to calculate the temperature correction coefficient corresponding to each intake air temperature data according to the intake air flow basic data corresponding to each intake air temperature data and the actual intake air flow data.

5. The explosion-proof diesel engine smoke control system according to claim 2, characterized in that: The data processing unit is also specifically used to calculate the product of the intake air flow basic data and the temperature correction coefficient to obtain the intake air flow data.

6. The explosion-proof diesel engine smoke control system according to claim 5, characterized in that: The data processing unit is further specifically used to obtain the product of the intake flow data and the number of strokes of the explosion-proof diesel engine to obtain a first product value; and obtain the product of the speed data and the number of cylinders of the explosion-proof diesel engine to obtain a second product value; The second product value is multiplied by 2 to obtain a third product value; and the quotient of the first product value divided by the third product value is calculated to obtain the stroke intake volume.

7. The explosion-proof diesel engine smoke control system according to claim 1, characterized in that: The data processing unit is also specifically used to construct an air-fuel ratio limit basic mapping table, a water temperature correction offset table, a water temperature correction coefficient mapping table, an atmospheric pressure correction offset mapping table and an atmospheric pressure correction coefficient mapping table; wherein the air-fuel ratio limit basic mapping table, the water temperature correction offset table, the atmospheric pressure correction offset mapping table and the atmospheric pressure correction coefficient mapping table are all two-dimensional tables, and the water temperature correction coefficient mapping table is a one-dimensional table; the rows of the air-fuel ratio limit basic mapping table represent the speed data, the columns of the air-fuel ratio limit basic mapping table represent the intake boost pressure data, and the fields of the air-fuel ratio limit basic mapping table represent the air-fuel ratio limit basic value; the rows of the water temperature correction offset table represent the speed data, the water temperature correction offset table represents the intake boost pressure data, and the fields of the air-fuel ratio limit basic mapping table represent the air-fuel ratio limit basic value. The columns of the offset table represent the intake boost pressure data, and the domain of the water temperature correction offset table represents the water temperature correction offset value; the rows of the water temperature correction coefficient mapping table represent the cooling water temperature data, and the domain of the water temperature correction coefficient mapping table represents the water temperature correction coefficient; the rows of the atmospheric pressure correction offset mapping table represent the speed data, the columns of the atmospheric pressure correction offset mapping table represent the intake boost pressure data, and the domain of the atmospheric pressure correction offset mapping table represents the atmospheric pressure correction offset value; the rows of the atmospheric pressure correction coefficient mapping table represent the cooling water temperature data, the columns of the atmospheric pressure correction coefficient mapping table represent the intake boost pressure data, and the domain of the atmospheric pressure correction coefficient mapping table represents the atmospheric pressure correction coefficient; The data processing unit is further specifically used to query the air-fuel ratio limit base value under the combination of the speed data and the intake boost pressure data in the air-fuel ratio limit base mapping table; query the water temperature correction offset value under the combination of the speed data and the intake boost pressure data in the water temperature correction offset table; query the water temperature correction coefficient corresponding to the cooling water temperature data in the water temperature correction coefficient mapping table; query the atmospheric pressure correction offset value under the combination of the speed data and the intake boost pressure data in the atmospheric pressure correction offset mapping table; query the atmospheric pressure correction coefficient under the combination of the cooling water temperature data and the intake boost pressure data in the atmospheric pressure correction coefficient mapping table; The data processing unit is further specifically configured to calculate the air-fuel ratio limit value by using the air-fuel ratio limit value base value, the water temperature correction offset value, the water temperature correction coefficient, the atmospheric pressure correction offset value, and the atmospheric pressure correction coefficient.

8. The explosion-proof diesel engine smoke control system according to claim 7, characterized in that: The data processing unit is also specifically used to calculate the quotient of the stroke intake volume and the air-fuel ratio limit value to obtain the smoke limit oil volume.

9. The explosion-proof diesel engine smoke control system according to claim 8, characterized in that: The data processing unit is further specifically used to construct an oil quantity to pulse width mapping table; wherein the oil quantity to pulse width mapping table is a two-dimensional table, wherein the rows of the oil quantity to pulse width mapping table represent the speed data, the columns of the oil quantity to pulse width mapping table represent the smoke limit oil quantity, and the domain of the oil quantity to pulse width mapping table represents the injection pulse width; The data processing unit is also specifically used to query the injection pulse width under the combination of the smoke limit oil quantity and the speed data in the oil quantity to pulse width mapping table.

10. A method for controlling smoke emission of an explosion-proof diesel engine, characterized in that: The explosion-proof diesel engine smoke control system applied to any one of claims 1 to 9 comprises the following steps: The data acquisition unit is used to collect the speed data, intake boost pressure data, cooling water temperature data, intake temperature data and atmospheric pressure data of the explosion-proof diesel engine; Calculating the intake flow data of the explosion-proof diesel engine according to the speed data, the intake boost pressure data and the intake temperature data using a data processing unit; Calculating the stroke intake volume by using a data processing unit according to the intake flow data, the speed data, the number of cylinders of the explosion-proof diesel engine and the number of strokes of the explosion-proof diesel engine; wherein the stroke intake volume is the intake flow of the cylinder of the explosion-proof diesel engine in one stroke; Calculating an air-fuel ratio limit value using a data processing unit according to the intake boost pressure data, the intake temperature data, the speed data, the cooling water temperature data, and the atmospheric pressure data; Calculating the smoke limit oil quantity according to the speed data, the stroke air intake volume and the air-fuel ratio limit value by using a data processing unit; calculating the injection pulse width of the explosion-proof diesel engine according to the smoke limit oil quantity; outputting a valve control signal according to the injection pulse width using an injection control unit; The fuel injection control valve is used to change its on / off state under the control of the valve control signal, thereby controlling the fuel injection amount of the explosion-proof diesel engine.

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