Hybrid variable composition gaseous fuel engine supply system and method of supplying same

Abstract

The application relates to a mixed variable component gas fuel engine supply system and a supply method thereof. The application relates to a gas fuel engine supply system. The application is used for solving the problem that the existing gas fuel engine supply system cannot adapt to fuel variable components. The supply system comprises a total pipe air intake adjusting valve, an air intake total pipe, a gas supply total pipe, a gas premixing chamber, a natural gas premixing chamber common rail injector, a coal bed gas injector, a natural gas rail, a natural gas storage tank, a coal bed gas storage tank, a natural gas manifold common rail injector, an exhaust total pipe, an exhaust oxygen sensor and a control unit. The natural gas manifold common rail injector is arranged on the air intake manifold. The exhaust oxygen sensor is arranged on the exhaust end of the exhaust total pipe. The natural gas premixing chamber common rail injector and the coal bed gas injector are arranged on the gas premixing chamber. The application is used for mixed variable component gas fuel engine fuel supply.

Description

TECHNICAL FIELD

[0001] The present application relates to a gaseous fuel engine supply system, in particular to a hybrid variable component gaseous fuel engine supply system and a supply method thereof. BACKGROUND

[0002] Coalbed gas, also known as coalbed methane, is stored in coal seams and surrounding rock layers, and is a kind of unconventional natural gas associated with coal that has not been commercially used on a large scale. It is very suitable for use as an alternative fuel for internal combustion engines. The high-grade heat energy generated by burning coalbed gas in coal mining areas can be used as electric energy, and the low-grade heat energy can be recovered and utilized to convert into heat and cold load required energy. This not only realizes the development and utilization of coalbed gas and the development of coalbed gas industry, but also reduces the risk of coal mine accidents, develops clean energy, reduces the consumption of traditional fossil energy, reduces greenhouse gas emissions, and brings huge economic benefits.

[0003] However, coalbed gas has a complex composition, containing not only hydrocarbons such as methane and ethane, but also a small amount of non-combustible substances such as nitrogen and carbon dioxide. The composition of coalbed gas also changes with conditions such as region and coal seam depth, which is not conducive to the stable operation of gaseous fuel engines and cannot guarantee the continuous operation of the engine in the high efficiency range. Therefore, a special supply system is needed to keep the composition of the fuel gas relatively stable.

[0004] Publication No. CN108691693A relates to a natural gas engine fuel supply system with a reflux pipe and a control method, which can quickly respond to changes in the load of the natural gas engine, restore the speed faster, improve the dynamic response, and shorten the response time. However, it only considers the case where the fuel component is fixed and cannot adapt to the case where the fuel component changes. SUMMARY

[0005] The present application is to solve the problem that the existing gaseous fuel engine supply system cannot adapt to the case where the fuel component changes, and further proposes a hybrid variable component gaseous fuel engine supply system and a supply method thereof.

[0006] The technical solution adopted by the present application to solve the above technical problems is:

[0007] The mixed variable component gas fuel engine supply system comprises a manifold intake regulating valve, an intake manifold, a gas supply manifold, a gas premixing chamber, a natural gas premixing chamber common rail injector, a coal bed gas injector, a natural gas rail, a natural gas tank, a coal bed gas tank, a natural gas manifold common rail injector, an exhaust manifold, an exhaust oxygen sensor and a control unit, the intake manifold is connected with the manifold intake regulating valve, the exhaust end of the intake manifold is connected with the intake end of an intake manifold, the intake manifold is provided with the natural gas manifold common rail injector, the intake end of the natural gas manifold common rail injector is connected with the exhaust end of the natural gas rail, the exhaust end of the intake manifold is connected with the intake end of the gas fuel engine, the exhaust end of the gas fuel engine is connected with the intake end of the exhaust manifold, the exhaust end of the exhaust manifold is provided with the exhaust oxygen sensor, the exhaust end of the gas premixing chamber is connected with the intake manifold through the gas supply manifold, the gas premixing chamber is provided with the natural gas premixing chamber common rail injector and the coal bed gas injector, the intake end of the natural gas premixing chamber common rail injector is connected with the exhaust end of the natural gas rail, the intake end of the natural gas rail is connected with the exhaust end of the natural gas tank through a natural gas pipeline, the intake end of the coal bed gas injector is connected with the exhaust end of the coal bed gas tank through a coal bed gas pipeline, and the exhaust oxygen sensor, the manifold intake regulating valve, the coal bed gas injector, the natural gas premixing chamber common rail injector and the natural gas manifold common rail injector are electrically connected with the control unit.

[0008] Further, the connection between the gas supply manifold and the intake manifold is arranged at the front side of the manifold intake regulating valve.

[0009] Further, the signal output end of the exhaust oxygen sensor is connected with the signal input end of the control unit, and the signal output end of the control unit is connected with the signal input end of the manifold intake regulating valve, the coal bed gas injector, the natural gas premixing chamber common rail injector and the natural gas manifold common rail injector respectively.

[0010] Further, the natural gas pipeline is connected with a natural gas pressure regulating valve.

[0011] Further, the coal bed gas pipeline is connected with a coal bed gas pressure regulating valve.

[0012] Further, the exhaust oxygen sensor is a wide-range oxygen sensor.

[0013] Further, the control unit is an ECU electronic control unit.

[0014] The supply method of the mixed variable component gas fuel engine supply system comprises a mixed supply mode, and the mixed supply mode comprises the following steps.

[0015] The control unit receives the signal of the exhaust oxygen sensor, analyzes the combustion condition of the gas fuel engine according to the signal, obtains the air-fuel ratio and the supply ratio of the coalbed gas and the natural gas matched with the combustion condition, and transmits the control signal to the total pipe intake adjusting valve through the control unit to adjust the total supply amount of the mixed gas at the exhaust end of the intake total pipe, and at the same time, the control unit transmits the control signal to the coalbed gas injector and the natural gas manifold common rail injector to control the injection ratio of the coalbed gas and the natural gas, at this time, the natural gas premixing chamber common rail injector does not work, the coalbed gas injector injects the coalbed gas into the gas premixing chamber, and the coalbed gas is transported to the intake total pipe and then to the intake manifold through the gas supply total pipe, and the natural gas manifold common rail injector injects the natural gas into the intake manifold at the same time, and the mixed gas in the intake manifold enters the gas fuel engine.

[0016] The supply method of the hybrid variable component gas fuel engine supply system comprises a total pipe supply mode, and the total pipe supply mode comprises the following steps:

[0017] The control unit receives the signal of the exhaust oxygen sensor, analyzes the combustion condition of the gas fuel engine according to the signal, obtains the air-fuel ratio and the supply ratio of the coalbed gas and the natural gas matched with the combustion condition, and transmits the control signal to the total pipe intake adjusting valve through the control unit to adjust the total supply amount of the mixed gas at the exhaust end of the intake total pipe, and at the same time, the control unit transmits the control signal to the coalbed gas injector and the natural gas premixing chamber common rail injector to control the injection ratio of the coalbed gas and the natural gas in the gas premixing chamber, and the mixing is completed in the gas premixing chamber, and the mixed gas is transported to the intake total pipe and then to the intake manifold through the gas supply total pipe, at this time, the natural gas manifold common rail injector does not work, and the mixed gas in the intake manifold enters the gas fuel engine.

[0018] Further, the injection pressure of the coalbed gas injector and the natural gas premixing chamber common rail injector is the same or different.

[0019] Compared with the prior art, the present application has the following beneficial effects:

[0020] 1. The supply ratio of the coalbed gas and the natural gas is adjusted by adopting the hybrid supply mode, wherein the coalbed gas is supplied through the total pipe, and the natural gas is supplied through the manifold, which can ensure the simple structure of the coalbed gas supply and guarantee the accuracy and rapid response of the gas component regulation.

[0021] 2. The exhaust oxygen sensor is arranged on the exhaust total pipe to monitor the engine combustion condition, and the ECU control unit converts the signal collected by the exhaust oxygen sensor into a control signal for regulating and controlling the supply of the coalbed gas and the natural gas, so that the closed-loop control is realized, and when the working condition of the engine changes or the composition of the coalbed gas changes, the system can be automatically adjusted quickly, thereby improving the stability of the system.

[0022] 3. The system has two supply modes, namely mixed supply mode and manifold supply mode, and can ensure that the system can still operate in the manifold supply mode when the mixed supply mode cannot operate normally, so that the system has certain risk resistance. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 is a schematic diagram of the overall structure of the present application; DETAILED DESCRIPTION

[0024] Specific implementation one: combined Figure 1 In this embodiment, a mixed variable component gaseous fuel engine supply system includes a manifold intake regulating valve 1, an intake manifold 2, a gas supply manifold 3, a gas premixing chamber 4, a natural gas premixing chamber common rail injector 5, a coal bed gas injector 6, a natural gas rail 7, a natural gas storage tank 10, a coal bed gas storage tank 11, a natural gas manifold common rail injector 12, an exhaust manifold 13, an exhaust oxygen sensor 14 and a control unit 15. The intake manifold 2 is connected with the manifold intake regulating valve 1. The gas outlet end of the intake manifold 2 is connected with the gas inlet end of the intake manifold. The intake manifold is provided with the natural gas manifold common rail injector 12. The gas inlet end of the natural gas manifold common rail injector 12 is connected with the gas outlet end of the natural gas rail 7. The gas outlet end of the intake manifold is connected with the gas inlet end of the gaseous fuel engine. The gas outlet end of the gaseous fuel engine is connected with the gas inlet end of the exhaust manifold 13. The gas outlet end of the exhaust manifold 13 is provided with the exhaust oxygen sensor 14. The gas outlet end of the gas premixing chamber 4 is connected with the intake manifold 2 through the gas supply manifold 3. The gas premixing chamber 4 is provided with the natural gas premixing chamber common rail injector 5 and the coal bed gas injector 6. The gas inlet end of the natural gas premixing chamber common rail injector 5 is connected with the gas outlet end of the natural gas rail 7. The gas inlet end of the natural gas rail 7 is connected with the gas outlet end of the natural gas storage tank 10 through a natural gas pipeline. The gas inlet end of the coal bed gas injector 6 is connected with the gas outlet end of the coal bed gas storage tank 11 through a coal bed gas pipeline. The exhaust oxygen sensor 14, the manifold intake regulating valve 1, the coal bed gas injector 6, the natural gas premixing chamber common rail injector 5 and the natural gas manifold common rail injector 12 are electrically connected with the control unit 15.

[0025] The manifold intake regulating valve 1 is arranged in the intake manifold 2 and can adjust the total amount of gas supplied to the gaseous fuel engine. The exhaust oxygen sensor 14 is arranged in the exhaust manifold 13 and can sense the combustion condition of the gaseous fuel engine by detecting the composition of the exhaust gas and feed back the signal to the control unit 15.

[0026] The supply system comprises two supply modes: a mixed supply mode, in which the control unit 15 controls the coalbed gas injector 6 and the natural gas manifold common rail injector 12 to work, so as to realize accurate and rapid response of the gas component regulation; and a manifold supply mode, in which the control unit 15 controls the coalbed gas injector 6 and the natural gas premixing chamber common rail injector 5 to work, so as to ensure that the system can work in the manifold supply mode when the mixed supply mode cannot work normally, and the system has a certain risk resistance.

[0027] The gas premixing chamber 4 is a small chamber, which is provided with a coalbed gas injector 6 and a natural gas premixing chamber common rail injector 5, and the injection pressures of the two injectors can be different. In the mixed supply mode, the coalbed gas injector 6 sprays into the gas premixing chamber 4, and the gas is transported to the intake manifold 2 through the gas supply manifold 3; in the manifold supply mode, the coalbed gas injector 6 and the natural gas premixing chamber common rail injector 5 spray into the gas premixing chamber 4 at the same time, the sprayed gas is mixed in the gas premixing chamber 4, and the gas is transported to the intake manifold 2 through the gas supply manifold 3.

[0028] The number of the gas outlet ends of the intake manifold is consistent with the number of the cylinders of the gas fuel engine, and the number of the natural gas manifold common rail injectors 12 is consistent with the number of the cylinders, which are arranged at the gas outlet ends of the intake manifold, respectively.

[0029] The gas outlet ends of the gas fuel engine are connected with the gas inlet ends of the exhaust manifold 13 through the exhaust manifold.

[0030] The purpose of the present application is to provide a mixed variable component gas fuel engine supply system capable of realizing multiple supply modes, which can quickly respond when the component ratio of coalbed gas changes, and the system also has a certain risk resistance.

[0031] Specific implementation mode two: combined with Figure 1 In this implementation mode, the connection between the gas supply manifold 3 and the intake manifold 2 is arranged at the front side of the manifold intake adjusting valve 1. The technical features not disclosed in this implementation mode are the same as those in the specific implementation mode one.

[0032] Specific implementation mode three: combined with Figure 1 In this implementation mode, the signal output end of the tail gas oxygen sensor 14 is connected with the signal input end of the control unit 15, and the signal output end of the control unit 15 is connected with the signal input ends of the manifold intake adjusting valve 1, the coalbed gas injector 6, the natural gas premixing chamber common rail injector 5 and the natural gas manifold common rail injector 12, respectively. The technical features not disclosed in this implementation mode are the same as those in the specific implementation mode two.

[0033] The control unit 15 receives signals from the exhaust oxygen sensor 14 and outputs control signals to the manifold intake adjusting valve 1, the coalbed methane injector 6, the natural gas premixing chamber common rail injector 5 and the natural gas manifold common rail injector 12.

[0034] Specific embodiment four: combination Figure 1 This embodiment is described, and the natural gas pipeline of this embodiment is connected with a natural gas pressure regulating valve 8. The technical features not disclosed in this embodiment are the same as those of specific embodiment one.

[0035] Specific embodiment five: combination Figure 1 This embodiment is described, and the coalbed methane pipeline of this embodiment is connected with a coalbed methane pressure regulating valve 9. The technical features not disclosed in this embodiment are the same as those of specific embodiment one.

[0036] Specific embodiment six: combination Figure 1 This embodiment is described, and the exhaust oxygen sensor 14 of this embodiment is a wide-range oxygen sensor. The technical features not disclosed in this embodiment are the same as those of specific embodiment one.

[0037] The exhaust oxygen sensor 14 is a wide-range oxygen sensor, which can quickly and accurately obtain the oxygen concentration of the exhaust gas of the exhaust manifold and transmit the signal to the control unit 15.

[0038] Specific embodiment seven: combination Figure 1 This embodiment is described, and the control unit 15 of this embodiment is an ECU electronic control unit. The technical features not disclosed in this embodiment are the same as those of specific embodiment one.

[0039] Specific embodiment eight: combination Figure 1 This embodiment is described, and the supply method of the mixed type variable component gas fuel engine supply system of this embodiment includes a mixed type supply mode, which includes the following steps:

[0040] The control unit 15 receives signals from the exhaust oxygen sensor 14, analyzes the combustion condition of the gas fuel engine according to the signals, obtains the air-fuel ratio and the supply ratio of coalbed methane and natural gas matched with the combustion condition, and transmits control signals to the manifold intake adjusting valve 1 through the control unit 15 to adjust the total supply amount of the mixed gas at the exhaust end of the intake manifold 2. At the same time, the control unit 15 transmits control signals to the coalbed methane injector 6 and the natural gas manifold common rail injector 12 to control the injection ratio of coalbed methane and natural gas. At this time, the natural gas premixing chamber common rail injector 5 does not work, the coalbed methane injector 6 injects coalbed methane into the gas premixing chamber 4, and the coalbed methane is transported to the intake manifold 2 through the gas supply manifold 3 and then enters the intake manifold, the natural gas manifold common rail injector 12 simultaneously injects natural gas into the intake manifold, and the mixed gas in the intake manifold enters the gas fuel engine.

[0041] Specific implementation nine: combination Figure 1 The embodiment is described, and the supply method of the hybrid variable component gas fuel engine supply system of the embodiment includes a manifold supply mode, which includes the following steps:

[0042] After the control unit 15 receives the signal of the exhaust gas oxygen sensor 14, the combustion condition of the gas fuel engine is analyzed according to the signal, the air-fuel ratio matched with the combustion condition, and the supply ratio of coal bed gas and natural gas are obtained, and the control signal is transmitted to the manifold intake air regulating valve 1 through the control unit 15 to adjust the total supply amount of the mixed gas at the outlet of the intake manifold 2, and at the same time, the control unit 15 transmits the control signal to the coal bed gas injector 6 and the natural gas premixing chamber common rail injector 5 to control the injection ratio of the coal bed gas and the natural gas in the gas premixing chamber 4, and the mixing is completed in the gas premixing chamber 4, and then the mixed gas is delivered to the intake manifold 2 through the gas supply manifold 3 and enters the intake manifold. At this time, the natural gas manifold common rail injector 12 does not work, and the mixed gas in the intake manifold enters the gas fuel engine.

[0043] The manifold supply mode is a backup supply mode when the natural gas manifold common rail injector 12 fails.

[0044] Specific implementation ten: combination Figure 1 The embodiment is described, and the coal bed gas injector 6 and the natural gas premixing chamber common rail injector 5 in the embodiment have the same or different injection pressures when injecting. The technical features not disclosed in the embodiment are the same as those in specific implementation nine.

[0045] The above is only a preferred embodiment of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A hybrid variable composition gaseous fuel engine supply system characterized by: It includes the total pipe intake regulating valve (1), the intake manifold (2), the gas supply manifold (3), the gas premixing chamber (4), the natural gas premixing chamber common rail injector (5), the coal bed gas injector (6), the natural gas rail (7), the natural gas storage tank (10), the coal bed gas storage tank (11), the natural gas manifold common rail injector (12), the exhaust manifold (13), the tail gas oxygen sensor (14) and the control unit (15), the intake manifold (2) is connected with the total pipe intake regulating valve (1), the exhaust end of the intake manifold (2) is connected with the intake end of the intake manifold, the intake manifold is provided with the natural gas manifold common rail injector (12), the intake end of the natural gas manifold common rail injector (12) is connected with the exhaust end of the natural gas rail (7), the exhaust end of the intake manifold is connected with the intake end of the gas fuel engine, the exhaust end of the gas fuel engine is connected with the intake end of the exhaust manifold (13), the exhaust end of the exhaust manifold (13) is provided with the tail gas oxygen sensor (14), the exhaust end of the gas premixing chamber (4) is connected with the intake manifold (2) through the gas supply manifold (3), the gas premixing chamber (4) is provided with the natural gas premixing chamber common rail injector (5) and the coal bed gas injector (6), the intake end of the natural gas premixing chamber common rail injector (5) is connected with the exhaust end of the natural gas rail (7), the intake end of the natural gas rail (7) is connected with the exhaust end of the natural gas storage tank (10) through the natural gas pipeline, the intake end of the coal bed gas injector (6) is connected with the exhaust end of the coal bed gas storage tank (11) through the coal bed gas pipeline, the tail gas oxygen sensor (14), the total pipe intake regulating valve (1), the coal bed gas injector (6), the natural gas premixing chamber common rail injector (5) and the natural gas manifold common rail injector (12) are electrically connected with the control unit (15) respectively.

2. The hybrid variable composition gaseous fuel engine supply system of claim 1, wherein: The connection between the gas supply manifold (3) and the intake manifold (2) is arranged at the front side of the total pipe intake regulating valve (1).

3. The hybrid variable composition gaseous fuel engine supply system of claim 2, wherein: The signal output end of the tail gas oxygen sensor (14) is connected with the signal input end of the control unit (15), and the signal output end of the control unit (15) is connected with the signal input end of the total pipe intake regulating valve (1), the coal bed gas injector (6), the natural gas premixing chamber common rail injector (5) and the natural gas manifold common rail injector (12) respectively.

4. The hybrid variable composition gaseous fuel engine supply system of claim 1, wherein: The natural gas pipeline is connected with the natural gas pressure regulating valve (8).

5. The hybrid variable composition gaseous fuel engine supply system of claim 1, wherein: The coal bed gas pipeline is connected with the coal bed gas pressure regulating valve (9).

6. The hybrid variable composition gaseous fuel engine supply system of claim 1, wherein: The tail gas oxygen sensor (14) is a wide-range oxygen sensor.

7. The hybrid variable composition gaseous fuel engine supply system of claim 1, wherein: The control unit (15) is an ECU electronic control unit.

8. A method of supplying a mixed variable composition gas fuel engine system according to any one of claims 1 to 7, characterized by: The method comprises a mixed supply mode, and the mixed supply mode comprises the following steps: The control unit (15) receives the signal of the exhaust oxygen sensor (14), analyzes the combustion condition of the gas fuel engine according to the signal, obtains the air-fuel ratio and the supply ratio of the coalbed gas and the natural gas matched with the combustion condition, and transmits the control signal to the total pipe intake adjusting valve (1) through the control unit (15) to adjust the total supply amount of the mixed gas at the outlet end of the intake total pipe (2), and at the same time, the control unit (15) transmits the control signal to the coalbed gas injector (6) and the natural gas manifold common rail injector (12) to control the injection ratio of the coalbed gas and the natural gas, at this time, the natural gas premixing chamber common rail injector (5) does not work, the coalbed gas injector (6) injects the coalbed gas into the gas premixing chamber (4), and the mixed gas is transported to the intake total pipe (2) through the gas supply total pipe (3) and then enters the intake manifold, the natural gas manifold common rail injector (12) injects the natural gas into the intake manifold at the same time, and the mixed gas in the intake manifold enters the gas fuel engine.

9. A method of supplying a mixed variable composition gas fuel engine system according to any one of claims 1 to 7, characterized by: The method comprises a total pipe supply mode, and the total pipe supply mode comprises the following steps: After the control unit (15) receives the signal of the exhaust oxygen sensor (14), the combustion condition of the gas fuel engine is analyzed according to the signal, the air-fuel ratio and the supply ratio of the coalbed gas and the natural gas matched with the combustion condition are obtained, the control signal is transmitted to the total pipe intake adjusting valve (1) through the control unit (15) to adjust the total supply amount of the mixed gas at the outlet end of the intake total pipe (2), and at the same time, the control signal is transmitted to the coalbed gas injector (6) and the natural gas premixing chamber common rail injector (5) to control the injection ratio of the coalbed gas and the natural gas in the gas premixing chamber (4), and the mixing is completed in the gas premixing chamber (4), the mixed gas is transported to the intake total pipe (2) through the gas supply total pipe (3) and then enters the intake manifold, at this time, the natural gas manifold common rail injector (12) does not work, and the mixed gas in the intake manifold enters the gas fuel engine.

10. The method of claim 9, wherein the method further comprises: determining a fueling amount of the gaseous fuel to be supplied to the engine based on the engine operating condition; and determining a fueling amount of the liquid fuel to be supplied to the engine based on the engine operating condition. The injection pressures of the coalbed gas injector (6) and the natural gas premixing chamber common rail injector (5) are the same or different.

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