A control device and control method for a gas generator set

Abstract

The present invention relates to the field of environmental protection technology, and specifically to a control device and a control method for a gas generator set, wherein the control device of the gas generator set includes: a flue gas pipe, a cooler, a gas compressor, a fuel gas pipe, a self-mixing pulse flow valve and a controller, wherein the flue gas pipe is used to introduce high-temperature flue gas; the cooler is used to cool the flue gas pipe; the fuel gas pipe is used to introduce fuel gas, the fuel gas pipe and the flue gas pipe are connected through a branch, and a differential pressure transmitter is provided on the branch; one end of the self-mixing pulse flow valve is connected to the outlet of the flue gas pipe, and the self-mixing pulse flow valve is used to communicate with the engine cylinder intake branch pipe; the controller controls the power of the gas compressor and the flow of the self-mixing pulse flow valve according to the differential pressure transmitter and an input device for detecting engine parameters. In the present application, the flue gas of the self-mixing pulse flow valve is adjusted to be mixed into the fuel gas pipeline as an inert gas, which is used to adjust the temperature in the engine cylinder, thereby achieving the purpose of reducing the flue gas nitrogen oxide emission concentration.

Description

Technical Field

[0001] The present invention relates to the technical field of environmental protection, and in particular to a control device and a control method for a gas generator set. Background Art

[0002] When a gas engine is working, high temperature is generated inside its combustion chamber. When the gas concentration and pressure fluctuate, the air-fuel ratio of the gas mixture entering the cylinder for combustion cannot be accurately maintained at the optimal ratio due to the time delay of the control system's action. Often when the engine is running at high load, the concentration of the gas mixture will be higher, resulting in uneven combustion and high temperature in the engine cylinder. Under the action of high temperature, the generation rate of nitrogen oxides is accelerated, resulting in an increase in the concentration of nitrogen oxides in the exhaust gas. Summary of the invention

[0003] (I) One of the technical problems to be solved by the present invention is that the existing gas engine has a problem of high temperature in the engine cylinder.

[0004] (II) Technical solution

[0005] In order to solve the above technical problems, the present invention provides a control device for a gas generator set, comprising: a flue gas pipe, the flue gas pipe being used to introduce high-temperature flue gas;

[0006] A cooler, the cooler is used to cool the flue gas pipe;

[0007] A gas compressor, the gas compressor is used to increase the pressure of the flue gas in the flue pipe after being cooled;

[0008] A gas pipe, the gas pipe is used to introduce gas, the gas pipe is connected to the flue gas pipe through a branch, and a differential pressure transmitter is provided on the branch;

[0009] A self-mixing pulse flow valve, one end of which is connected to the outlet of the smoke pipe, and the self-mixing pulse flow valve is used to be connected to the engine cylinder intake branch pipe;

[0010] A controller controls the power of the gas compressor and the flow of the self-mixing pulse flow valve according to the differential pressure transmitter and an input device for detecting engine parameters.

[0011] According to one embodiment of the present invention, a self-mixing pulse flow valve includes a shell and an electromagnetic coil, a movable valve stem, a spring and a conical valve seat arranged in the shell; the shell is provided with an air inlet piece connected to the outlet of the smoke pipe, and the shell is provided with a base air outlet matching the conical valve seat, and the air outlet is connected to the engine cylinder intake branch pipe; the controller controls the electromagnetic coil to be energized to drive the movable valve stem to move, thereby connecting the air inlet piece and the air outlet, and the electromagnetic coil is disconnected from the air inlet piece and the air outlet under the action of the spring after the power is cut off.

[0012] According to an embodiment of the present invention, an iron core matching the electromagnetic coil is disposed on the movable valve stem.

[0013] According to one embodiment of the present invention, the self-mixing pulse flow valve further comprises a mixing impeller disposed in the housing, and the mixing impeller is disposed at the connection point between the air inlet and the air outlet.

[0014] According to one embodiment of the present invention, a first conical surface is provided at one end of the movable valve stem close to the conical valve seat, and a second conical surface matching the first conical surface is provided on the conical valve seat. After the movable valve stem moves, it is in close contact with the second conical surface of the conical valve seat.

[0015] According to one embodiment of the present invention, a first external thread is provided on the air intake piece, and a first internal thread matching the first external thread is provided on the smoke pipe; a second external thread is provided on the shell near the air outlet, and the second external thread is used to match the second internal thread of the engine cylinder intake branch pipe.

[0016] According to an embodiment of the present invention, the input device for detecting engine parameters is an engine control system, and the controller controls the flow of the self-mixing pulse flow valve according to a signal from the engine control system.

[0017] According to one embodiment of the present invention, there are multiple self-mixing pulse flow valves, and the number of the multiple self-mixing pulse flow valves matches the number of cylinders of the engine.

[0018] According to one embodiment of the present invention, the cooler comprises a water pipe, cooling water is passed into the water pipe, and is discharged after heat exchange with the flue gas pipe.

[0019] The present invention also provides a control method for a gas generator set, using the control device for the gas generator set as described above, wherein the specific steps are:

[0020] Obtaining operating parameters of the engine and parameters of the differential pressure transmitter 1;

[0021] Controlling the gas compressor according to the parameters of the differential pressure transmitter 1 so that the differential pressure between the gas pipe and the flue gas pipe reaches a preset differential pressure;

[0022] The flow of a self-mixing pulse flow valve connected to the gas pipe and the engine cylinder intake branch pipe is controlled according to the operating parameters of the engine, so that the temperature in the cylinder of the engine reaches a preset temperature.

[0023] Beneficial effects of the present invention: In the control device of the gas generator set provided in the present application, a self-mixing pulse flow valve is installed at the inlet position of the intake branch pipe of each cylinder of the machine body, and the cooler and the gas compressor are connected in sequence with a flue gas pipe. The controller adjusts the outlet pressure of the compressor by receiving the operating status data of the engine and the signal of the differential pressure transmitter 1, keeps the pressure at the outlet of the flue gas pipe and the pressure difference of the gas intake pipeline stable, and at the same time adjusts the flue gas of the self-mixing pulse flow valve to be mixed into the gas pipeline as an inert gas to adjust the temperature in the engine cylinder, thereby achieving the purpose of reducing the emission concentration of nitrogen oxides in the flue gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The advantages of the above and / or additional aspects of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0025] Figure 1 This is a schematic diagram of a normal structure of a control device for a gas generator set according to an embodiment of the present invention;

[0026] Figure 2 A schematic structural diagram of a self-mixing pulse flow valve provided in one embodiment of the present invention.

[0027] Reference numerals are as follows:

[0028] 1. differential pressure transmitter, 2. cooler, 3. gas compressor, 4. controller, 5. self-mixing pulse flow valve, 501. upper shell, 502. iron core, 503. electromagnetic coil, 504. upper shell connecting flange blind plate, 505. fixed baffle, 506. movable valve stem, 507. lower shell, 508. spring, 509. air inlet, 5010. conical valve seat, 5011. mixing impeller, 5012. mixing impeller fixed shaft, 5013. air outlet. DETAILED DESCRIPTION

[0029] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0030] like Figure 1 and Figure 2As shown, the present invention provides a control device for a gas generator set, comprising: a flue gas pipe, a cooler 2, a gas compressor 3, a fuel gas pipe, a self-mixing pulse flow valve 5 and a controller 4, wherein the flue gas pipe is used to introduce high-temperature flue gas; the cooler 2 is used to cool the flue gas pipe; the gas compressor 3 is used to pressurize the cooled flue gas in the flue gas pipe; the gas pipe is used to introduce fuel gas (the fuel gas in this embodiment is a gas-air mixture), the fuel gas pipe and the flue gas pipe are connected through a branch, and a pressure differential transmitter 1 is provided on the branch; one end of the self-mixing pulse flow valve 5 is connected to the outlet of the flue gas pipe, and the self-mixing pulse flow valve 5 is used to be connected to the engine cylinder intake branch pipe; the controller 4 controls the power of the gas compressor 3 and the flow of the self-mixing pulse flow valve 5 according to the pressure differential transmitter 1 and an input device for detecting engine parameters.

[0031] Specifically, the self-mixing pulse flow valve 5 is installed at the inlet position of the intake branch pipe of each cylinder of the engine body, and the cooler 2 and the gas compressor 3 are connected in sequence with the flue gas pipe. The controller 4 adjusts the outlet pressure of the compressor by receiving the operating status data of the engine and the signal of the pressure difference transmitter 1, so as to keep the pressure at the outlet of the flue gas pipe and the pressure difference of the gas intake pipeline stable. At the same time, the flue gas of the self-mixing pulse flow valve 5 is adjusted to be mixed into the gas pipeline as an inert gas to adjust the temperature in the engine cylinder, so as to achieve the purpose of reducing the emission concentration of nitrogen oxides in the flue gas.

[0032] According to one embodiment of the present invention, the self-mixing pulse flow valve 5 includes a shell and an electromagnetic coil 503, a movable valve stem 506, a spring 508 and a conical valve seat 5010 arranged in the shell; the shell is provided with an air inlet 509 connected to the outlet of the smoke pipe, and the shell is provided with a base air outlet 5013 matching the conical valve seat 5010, and the air outlet 5013 is connected to the engine cylinder intake branch pipe; the controller 4 controls the electromagnetic coil 503 to be energized to drive the movable valve stem 506 to move, thereby connecting the air inlet 509 and the air outlet 5013, and after the electromagnetic coil 503 is powered off, the air inlet 509 and the air outlet 5013 are disconnected under the action of the spring 508.

[0033] Specifically, the spring 508 is sleeved outside the movable valve stem 506, one end of the spring 508 is connected to the movable valve stem 506, and the other end of the spring 508 is connected to the housing, specifically, the spring 508 is connected to the housing through the fixed baffle 505. The housing may include an upper housing 501 and a lower housing 507 connected to the upper housing 501, and the upper housing 501 and the lower housing 507 are separated by an upper housing connecting flange blind plate 504.

[0034] According to an embodiment of the present invention, an iron core 502 matching the electromagnetic coil 503 is disposed on the movable valve stem 506 .

[0035] According to an embodiment of the present invention, the self-mixing pulse flow valve 5 further includes a mixing impeller 5011 disposed in the housing, and the mixing impeller 5011 is disposed at the connection point between the air inlet 509 and the air outlet 5013 .

[0036] Specifically, the mixing impeller 5011 is fixed below the conical valve seat 5010 through the mixing impeller fixed shaft 5012. The gas enters the engine cylinder intake branch pipe after passing through the mixing impeller 5011 through the bottom outlet 5013, and can fully mix the fuel gas and the smoke. The top is fixed in the upper shell 501 by the iron core 502 and the electromagnetic coil 503. The fixed baffle 505, the movable valve stem 506, and the spring 508 are installed in the closed space formed by the lower shell 507 and the conical valve seat 5010. When the electromagnetic coil 503 is energized, the movable valve stem 506 is lifted up under the action of magnetic force, and the gas enters the fuel gas pipe after passing through the air inlet 509 and the conical valve seat 5010 through the mixing impeller 5011 and the outlet 5013. When the electromagnetic coil 503 is de-energized, the movable valve stem 506 is sealed and contacted with the conical valve seat 5010 under the action of the spring 508 to cut off the gas passage.

[0037] According to one embodiment of the present invention, a first conical surface is provided at one end of the movable valve stem 506 close to the conical valve seat 5010, and a second conical surface matching the first conical surface is provided on the conical valve seat 5010. After the movable valve stem 506 moves, it is in close contact with the second conical surface of the conical valve seat 5010.

[0038] According to one embodiment of the present invention, a first external thread is provided on the air inlet piece 509, and a first internal thread matching the first external thread is provided on the smoke pipe; a second external thread is provided on the shell near the air outlet 5013, and the second external thread is used to match the second internal thread of the engine cylinder intake branch pipe.

[0039] According to an embodiment of the present invention, the input device for detecting engine parameters is an engine control system, and the controller 4 controls the flow of the self-mixing pulse flow valve 5 according to a signal from the engine control system.

[0040] Specifically, the engine control system is capable of transmitting cylinder temperature, exhaust temperature and / or power signals. The controller 4 has a built-in engine operation parameter table. By detecting the real-time temperature and power signals of the engine operation and comparing them with the built-in parameter table, the controller 4 controls and adjusts the deviation and calculates it. According to the calculation result, an adjustment signal is sent in real time to control the self-mixing pulse flow valve 5 to mix a certain proportion of flue gas into the engine cylinder intake branch pipe at different flow rates. Since the mixed flue gas is at the cylinder inlet, the combustion condition in the cylinder can be improved in time, which plays a role in adjusting the cylinder temperature and exhaust temperature, thereby controlling the nitrogen oxide emission content of the flue gas.

[0041] According to one embodiment of the present invention, there are multiple self-mixing pulse flow valves 5, and the number of the multiple self-mixing pulse flow valves 5 matches the number of cylinders of the engine.

[0042] According to one embodiment of the present invention, the cooler 2 includes a water pipe, cooling water is introduced into the water pipe, and is discharged after heat exchange with the flue gas pipe. One end of the water pipe is a cooling water inlet, and the other end of the water pipe is a cooling water outlet. The middle is a heat exchange part. After the heat exchange part exchanges heat with the flue gas pipe, the cooling water is heated and discharged, and the flue gas pipe is cooled.

[0043] The present invention also provides a method for controlling a gas generator set, using the control device for the gas generator set as described above:

[0044] Obtaining operating parameters of the engine and parameters of the differential pressure transmitter 1;

[0045] Controlling the gas compressor 3 according to the parameters of the differential pressure transmitter 1 so that the differential pressure between the gas pipe and the flue gas pipe reaches a preset differential pressure;

[0046] The flow rate of the self-mixing pulse flow valve 5 connected to the gas pipe and the engine cylinder intake branch pipe is controlled according to the operating parameters of the engine, so that the temperature in the cylinder of the engine reaches a preset temperature.

[0047] The control method mainly includes the following steps: a. When the engine is working, the self-mixing pulse flow valve 5 is inserted and fixed on the engine cylinder intake branch pipe through a threaded seal. b. The exhaust pipe is connected to the cooler 2, the gas compressor 3, and the self-mixing pulse flow valve 5 in sequence through the pipeline; in addition, a branch is drawn from the outlet of the gas compressor 3 and connected to the gas intake pipe, and the pressure differential transmitter 1 is connected to the branch. c. The communication cable of the controller 4 is connected to the engine control system and the pressure differential transmitter 1 respectively; the control cable of the controller 4 is connected to the gas compressor 3 and the self-mixing pulse flow valve 5 respectively. d. The communication unit of the controller 4 collects the cylinder temperature, exhaust temperature, current power and other signals of the engine through data communication with the engine control system, and receives the signal of the pressure differential transmitter 1 at the same time. e. The high-temperature flue gas is cooled to below 30°C by the cooler 2, and the pressure is increased by the gas compressor 3. The pressure is controlled by the controller 4 to perform frequency conversion regulation on the gas compressor 3, and the feedback signal comes from the pressure differential transmitter 1. The pressure difference is maintained at 30±2KPa to keep the flow of the pulse flow valve within the precise control range. f. The controller 4 has a built-in engine operation parameter table. By detecting the real-time temperature and power signal of the engine, and comparing them with the built-in parameter table, the controller 4 controls and adjusts the deviation, and sends out an adjustment signal in real time according to the calculation result to control the self-mixing pulse flow valve 5 to mix a certain proportion of flue gas into the gas intake pipe at different flow rates. Since the mixed flue gas is at the cylinder inlet, the combustion condition in the cylinder can be improved in time, and the cylinder temperature and exhaust temperature can be adjusted, thereby controlling the emission content of nitrogen oxides in the flue gas.

[0048] The control device of the gas generator set provided in the present application is used for reducing the original emission content of flue gas oxides in low-concentration gas engines, so that the operation of the engine is more in line with environmental protection requirements. The method is simple to control, easy to use, and low in cost. The entire device is easy to modify and install, and is suitable for different gas-fired reciprocating internal combustion engines.

[0049] In summary, in the control device of the gas generator set provided in the present application, the self-mixing pulse flow valve 5 is installed at the inlet position of the intake branch pipe of each cylinder of the body, and the cooler 2 and the gas compressor 3 are connected in sequence with the flue gas pipe. The controller 4 adjusts the outlet pressure of the compressor by receiving the operating status data of the engine and the signal of the pressure difference transmitter 1, so as to keep the pressure at the outlet of the flue gas pipe and the pressure difference of the gas intake pipeline stable. At the same time, the flue gas of the self-mixing pulse flow valve 5 is adjusted to be mixed into the gas pipeline as an inert gas to adjust the temperature in the engine cylinder, so as to achieve the purpose of reducing the emission concentration of nitrogen oxides in the flue gas.

[0050] In the description of the present invention, it should be noted that the terms "upper", "lower", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0051] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the inside of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, in the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0052] 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 spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A control device for a gas generator set, characterized in that: include: A flue gas pipe, the flue gas pipe being used to introduce high-temperature flue gas; A cooler, the cooler is used to cool the flue gas pipe; A gas compressor, the gas compressor is used to increase the pressure of the flue gas in the flue pipe after being cooled; A gas pipe, the gas pipe is used to introduce gas, the gas pipe is connected to the flue gas pipe through a branch, and a differential pressure transmitter is provided on the branch; A self-mixing pulse flow valve, one end of which is connected to the outlet of the smoke pipe, and the self-mixing pulse flow valve is used to be connected to the engine cylinder intake branch pipe; A controller, wherein the controller is capable of obtaining operating parameters of the engine and parameters of the differential pressure transmitter, and controlling the gas compressor according to the parameters of the differential pressure transmitter so that the differential pressure between the gas pipe and the flue gas pipe reaches a preset differential pressure; and controlling the flow of a self-mixing pulse flow valve connected to the gas pipe and the engine cylinder intake branch pipe according to the operating parameters of the engine so that the cylinder temperature of the engine reaches a preset temperature; The self-mixing pulse flow valve includes a shell and an electromagnetic coil, a movable valve stem, a spring and a conical valve seat arranged in the shell; the shell is provided with an air inlet connected to the outlet of the smoke pipe, and the shell is provided with a base air outlet matching the conical valve seat, and the air outlet is connected to the engine cylinder intake branch pipe; the controller controls the electromagnetic coil to be energized to drive the movable valve stem to move, thereby connecting the air inlet and the air outlet, and the electromagnetic coil is disconnected from the air inlet and the air outlet under the action of the spring after the power is cut off.

2. The control device of the gas generator set according to claim 1, characterized in that: The movable valve stem is provided with an iron core matching the electromagnetic coil.

3. The control device of the gas generator set according to claim 1, characterized in that: The self-mixing pulse flow valve further comprises a mixing impeller arranged in the housing, and the mixing impeller is arranged at the connection point between the air inlet and the air outlet.

4. The control device of the gas generator set according to claim 1, characterized in that: A first conical surface is arranged at one end of the movable valve stem close to the conical valve seat, and a second conical surface matching the first conical surface is arranged on the conical valve seat. After the movable valve stem moves, it is in close contact with the second conical surface of the conical valve seat.

5. The control device of the gas generator set according to claim 1, characterized in that: The air inlet is provided with a first external thread, and the smoke pipe is provided with a first internal thread matching the first external thread; the shell is provided with a second external thread near the air outlet, and the second external thread is used to match the second internal thread of the engine cylinder intake branch pipe.

6. The control device of the gas generator set according to claim 1, characterized in that: The input device for detecting engine parameters is an engine control system, and the controller controls the flow of the self-mixing pulse flow valve according to a signal from the engine control system.

7. The control device of the gas generator set according to claim 1, characterized in that: The number of the self-mixing pulse flow valves is multiple, and the number of the multiple self-mixing pulse flow valves matches the number of cylinders of the engine.

8. The control device of the gas generator set according to claim 1, characterized in that: The cooler comprises a water pipe, cooling water is introduced into the water pipe, and is discharged after heat exchange with the flue gas pipe.

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