Multi-fuel generator set control system, control method thereof and generator set

Abstract

The invention discloses a multi-fuel generator set control system and a control method thereof and a generator set, the control system comprises a fuel change-over switch, an engine starting switch, a carburetor, a fuel gas supply electric control valve, a signal detection module, an ignition device and a control device, the fuel change-over switch and the engine starting switch are respectively connected with the signal detection module; the carburetor, the fuel gas supply electric control valve, the signal detection module and the ignition device are connected with the control device. The signal detection module is used for detecting working state signals of the multi-fuel engine and sending the detected working state signals to the control device. And the control device is used for controlling the on-off state of the fuel gas supply electric control valve and the ignition time of the ignition device according to the received working state signal. According to the invention, the engine starting performance and the working stability of the multi-fuel generator set can be effectively improved when the multi-fuel generator set uses the gas fuel.

Description

Technical Field

[0001] The present invention relates to the technical field of generator sets, and in particular to a multi-fuel generator set control system and a control method thereof, and a generator set. Background Art

[0002] A multi-fuel generator set includes a multi-fuel engine and a generator. It is a power generation device that uses a multi-fuel engine to drive the generator to achieve power output. At present, there are two main types of multi-fuel generator sets according to the fuel type. One is a pure gas multi-fuel generator set, which uses at least two of the gas fuels such as LPG (liquefied petroleum gas), NG (natural gas), hydrogen, coal gas, and biogas as engine fuels. The other is a gas-liquid mixed multi-fuel generator set, which uses one or more gas fuels (such as LPG, NG, etc.) and a liquid fuel (such as gasoline, etc.) as engine fuels.

[0003] Multi-fuel generator sets are usually equipped with a fuel switching switch. Before the engine is started, the fuel switching switch is usually used to switch the type of fuel to be supplied to the engine's carburetor, and only one of the fuels is selected when the engine is working. On existing multi-fuel generators, a diaphragm pressure reducing valve is set between the gas fuel supply pipeline and the gas fuel inlet of the carburetor. When the selected fuel is gas fuel, negative pressure is generated in the engine cylinder during the engine intake stroke. The carburetor relies on the negative pressure to open the diaphragm pressure reducing valve, so that the gas fuel in the fuel supply pipeline enters the carburetor through the diaphragm pressure reducing valve, realizing the gas fuel supply during engine start-up and operation.

[0004] This method of passively opening the diaphragm pressure reducing valve through negative pressure to allow gas fuel to enter the engine requires extremely high precision in the matching of mechanical parts such as the engine and the diaphragm pressure reducing valve. Minor differences between parts (such as differences in the sealing of the engine cylinder block, differences in the spring elasticity of the diaphragm pressure reducing valve, etc.) may lead to inconsistent gas fuel intake at the same speed, thereby affecting the consistency and stability of the carburetor's intake of gas fuel into the engine cylinder block, making it difficult to ensure stable combustion effects and power generation efficiency, resulting in poor working stability of the multi-fuel generator set.

[0005] When the engine is started by gas fuel, this method of passively opening the diaphragm pressure reducing valve by negative pressure to achieve the gas fuel intake of the engine requires passive air supply, that is, when starting, the engine's starting motor rotates, and at the same time, by controlling the switch of the air door (i.e., the throttle), a negative pressure is generated in the carburetor, so that the diaphragm pressure reducing valve is opened, and the gas fuel supply device delivers the gas fuel to the carburetor through the diaphragm pressure reducing valve. However, the degree of opening of the diaphragm pressure reducing valve is related to the negative pressure of the carburetor. Only when the engine reaches a certain speed can the carburetor generate a negative pressure that opens the diaphragm pressure reducing valve, so that the gas fuel supply device delivers the gas fuel to the carburetor through the diaphragm pressure reducing valve. Due to the limitation of the starter motor starting time, the opening time of the diaphragm pressure reducing valve is short and the opening degree is small each time the starter motor works, which results in less gas fuel entering the carburetor each time. Therefore, this passive air supply method usually requires opening and closing the air door and intermittently starting the starter motor 3 to 6 times to successfully start the generator set. Therefore, there are problems of difficult starting and cumbersome operation.

[0006] Therefore, how to improve the engine starting performance of the multi-fuel generator set when using gas fuel and the working stability of the multi-fuel generator set is a problem that needs to be solved urgently. Summary of the invention

[0007] The present invention aims to solve at least one of the technical problems existing in the prior art, and in particular innovatively proposes a multi-fuel generator set control system, a control method and a generator set to improve the engine starting performance of the multi-fuel generator set when using gas fuel and the working stability of the multi-fuel generator set.

[0008] In order to achieve the above-mentioned object of the present invention, according to a first aspect of the present invention, the present invention provides a multi-fuel generator set control system, the multi-fuel generator set comprising a multi-fuel engine and a generator drivingly connected to the multi-fuel engine,

[0009] The control system includes a fuel switching switch, an engine start switch, a carburetor, a gas supply electric control valve, a signal detection module, an ignition device and a control device. The gas fuel supply pipeline of the multi-fuel engine is connected to the air inlet of the gas supply electric control valve, and the air outlet of the gas supply electric control valve is connected to the gas fuel inlet of the carburetor. The fuel switching switch and the engine start switch are respectively connected to the signal detection module, and the carburetor, the gas supply electric control valve, the signal detection module and the ignition device are respectively connected to the control device, wherein:

[0010] The signal detection module is used to detect the working state signal of the multi-fuel engine and send the detected working state signal to the control device;

[0011] The control device is used to control the switch state of the gas supply electric control valve and the ignition timing of the ignition device according to the received working state signal.

[0012] Preferably, the signal detection module comprises an engine start signal detection circuit, a fuel type detection circuit, a speed sensor and a power detection circuit, the signal output ends of the engine start signal detection circuit, the fuel type detection circuit, the speed sensor and the power detection circuit are respectively connected to the signal input ends of the control device, the signal input end of the engine start signal detection circuit is connected to the engine start switch, and the signal input end of the fuel type detection circuit is connected to the fuel switching switch, wherein,

[0013] The engine start signal detection circuit is used to detect the state of the engine start switch and output an engine start signal when the engine start switch is in the on state;

[0014] The fuel type detection circuit is used to detect the state of the fuel switching switch and output a corresponding fuel type signal;

[0015] The rotation speed sensor is used to detect the rotation speed signal of the fuel engine;

[0016] The power detection circuit is used to detect the current signal of the main winding of the generator and convert the current signal into a power generation signal.

[0017] Preferably, the signal detection module further comprises a temperature sensor, a signal output end of the temperature sensor is connected to a signal input end of the control device, and the temperature sensor is used to detect a cylinder temperature signal of the fuel engine.

[0018] Preferably, the signal detection module further comprises an oxygen sensor, a signal output terminal of the oxygen sensor is connected to a signal input terminal of the control device, and the oxygen sensor is used to detect an oxygen content signal in the exhaust gas of the fuel engine.

[0019] Preferably, the gas supply electrically controlled valve is a high-speed solenoid valve.

[0020] Preferably, the ignition device comprises an igniter and an ignition coil, the signal input end of the igniter is connected to the signal output end of the control device, and the signal output end of the igniter is connected to the signal input end of the ignition coil.

[0021] Preferably, the control device is integrated into an inverter controller of the multi-fuel generator set.

[0022] According to a second aspect of the present invention, the present invention provides a generator set, the generator set comprising any one of the above-mentioned multi-fuel generator set control systems.

[0023] According to a third aspect of the present invention, the present invention provides a control method for any of the above-mentioned multi-fuel generator set control systems, the control method comprising the following steps:

[0024] S1, detecting the working state signal of the multi-fuel engine through the signal detection module and sending it to the control device, wherein the working state signal at least includes an engine start signal, a fuel type signal, an engine speed signal and a power generation signal;

[0025] S2, controlling the switch state of the gas supply electric control valve and the ignition timing of the ignition device according to the received working state signal by the control device.

[0026] Preferably, in step S2, controlling the switch state of the gas supply electric control valve and the ignition timing of the ignition device according to the received working state signal by the control device includes:

[0027] S21, when the fuel type signal indicates that the currently selected engine fuel is gas fuel, searching for an injection pulse width calibration table and an ignition advance angle calibration table corresponding to the fuel type signal in a preset engine control parameter database according to the fuel type signal, wherein the engine control parameter database stores a plurality of injection pulse width calibration tables and ignition advance angle calibration tables of different fuel types, each of the injection pulse width calibration tables is provided with an injection pulse width corresponding to different engine speeds and power generation, and each of the ignition advance angle calibration tables is provided with an ignition advance angle corresponding to different engine speeds and power generation;

[0028] S22, searching for an injection pulse width matching the engine speed signal and the power generation signal in the injection pulse width calibration table based on the engine speed signal and the power generation signal, and searching for an ignition advance angle matching the engine speed signal and the power generation signal in the ignition advance angle calibration table based on the engine speed signal and the power generation signal;

[0029] S23, generating a corresponding PWM control signal based on the jet pulse width obtained by searching, and generating a corresponding ignition control signal based on the ignition advance angle obtained by searching;

[0030] S24, controlling the switch state of the gas supply electric control valve based on the PWM control signal, and controlling the ignition timing of the ignition device based on the ignition control signal.

[0031] It can be seen from the above scheme that the present invention provides a multi-fuel generator set control system, a control method thereof and a generator set, which controls the on and off connection between the gas fuel supply pipeline and the carburetor by replacing the pressure reducing valve with a gas supply electric control valve, and sets a signal detection module to detect the working status signal of the multi-fuel engine, and sets a control device to control the switching state of the gas supply electric control valve and the ignition time of the ignition device according to the received working status signal, thereby realizing active control of the gas fuel supply and the ignition of the engine according to the real-time state of the engine, which can effectively improve the engine starting performance of the multi-fuel generator set when using gas fuel and the working stability of the multi-fuel generator set.

[0032] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0034] Figure 1 It is a circuit principle block diagram of a multi-fuel generator set control system in a preferred embodiment of the present invention;

[0035] Figure 2 It is a flow chart of a control method of a multi-fuel generator set control system in a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0036] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0037] Those skilled in the art will appreciate that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those generally understood by those skilled in the art in the art to which the present invention belongs. It should also be understood that terms such as those defined in general dictionaries should be understood to have meanings consistent with the meanings in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless specifically defined.

[0038] like Figure 1 As shown, an embodiment of the present invention provides a multi-fuel generator set control system.

[0039] Specifically, in this embodiment, the multi-fuel generator set includes a multi-fuel engine and a generator driven and connected to the multi-fuel engine, the control system includes a fuel switching switch 1, an engine start switch 2, a carburetor 3, a gas supply electric control valve 4, a signal detection module 5, an ignition device 6 and a control device 7, the gas fuel supply pipeline of the multi-fuel engine is connected to the air inlet of the gas supply electric control valve 4, the air outlet of the gas supply electric control valve 4 is connected to the gas fuel inlet of the carburetor 3, the fuel switching switch 1 and the engine start switch 2 are respectively connected to the signal detection module 5, the carburetor 3, the gas supply electric control valve 4, the signal detection module 5 and the ignition device 6 are respectively connected to the control device 7, wherein,

[0040] The signal detection module 5 is used to detect the working state signal of the multi-fuel engine and send the detected working state signal to the control device 7;

[0041] The control device 7 is used to control the switch state of the gas supply electric control valve 4 and the ignition time of the ignition device 6 according to the received working state signal.

[0042] The working principle of the multi-fuel generator set control system in this embodiment is as follows:

[0043] When the multi-fuel generator set is started or operates normally, the signal detection module 5 is used to detect the status signals of the fuel switching switch 1 and the engine start switch 2, so as to detect the engine working status signals such as the fuel type signal and the engine start signal of the multi-fuel engine, and send the detected working status signal to the control device 7. The control device 7 controls the switching state of the gas supply electric control valve 4 and the ignition time of the ignition device 6 according to the received working status signal, so as to realize the active control of the engine gas supply and the precise control of the engine ignition time.

[0044] The multi-fuel generator set control system of this embodiment can actively control the supply of gas fuel and accurately control the ignition timing of the engine according to the real-time status of the engine. When the engine starts, the intake amount of gas fuel is no longer determined by the engine negative pressure, which effectively avoids the problem of inconsistent gas fuel intake amount at the same speed. It can effectively improve the engine starting performance of the multi-fuel generator set when using gas fuel and the working stability of the multi-fuel generator set, and achieve the effect of energy saving and emission reduction.

[0045] In one embodiment, the signal detection module 5 includes an engine start signal detection circuit 51, a fuel type detection circuit 52, a speed sensor 53 and a power detection circuit 54. The signal output ends of the engine start signal detection circuit 51, the fuel type detection circuit 52, the speed sensor 53 and the power detection circuit 54 are respectively connected to the signal input ends of the control device 7, the signal input end of the engine start signal detection circuit 51 is connected to the engine start switch 2, and the signal input end of the fuel type detection circuit 52 is connected to the fuel switching switch 1, wherein:

[0046] The engine start signal detection circuit 51 is used to detect the state of the engine start switch 2 and output the engine start signal when the engine start switch 2 is in the on state;

[0047] The fuel type detection circuit 52 is used to detect the state of the fuel switching switch 1 and output a corresponding fuel type signal;

[0048] The speed sensor 53 is used to detect the speed signal of the fuel engine;

[0049] The power detection circuit 54 is used to detect the current signal of the main winding of the generator and convert the current signal into a power generation signal.

[0050] The existing multi-fuel generator set control system only detects the engine speed and controls the ignition timing of the ignition device 6 according to the engine speed. The signal detection module 5 of this embodiment respectively detects the engine start signal, fuel type signal, speed signal and power generation power signal by setting the engine start signal detection circuit 51, the fuel type detection circuit 52, the speed sensor 53 and the power detection circuit 54, so that the control device 7 can output the corresponding solenoid valve control signal and the ignition control signal according to the engine start signal, the fuel type signal, the speed signal and the power generation power signal to respectively control the switch state of the gas supply electric control valve 4 and the ignition timing of the ignition device 6. On the basis of detecting the engine speed, the load is identified by detecting the power generation, thereby realizing the ignition angle control of different speeds and different loads, so that the engine can work in the best working condition at each load point, effectively improving the working efficiency of the multi-fuel generator and realizing energy saving and emission reduction.

[0051] In one embodiment, the signal detection module 5 further includes a temperature sensor 55, a signal output end of the temperature sensor 55 is connected to a signal input end of the control device 7, and the temperature sensor 55 is used to detect a cylinder temperature signal of the fuel engine.

[0052] In this embodiment, the signal detection module 5 detects the cylinder temperature signal of the engine by setting up a temperature sensor 55, so that the control device 7 can further adjust the gas fuel injection amount and throttle opening according to the cylinder temperature of the engine, thereby improving the starting performance of the engine when it is cold.

[0053] In one embodiment, the signal detection module 5 further includes an oxygen sensor 56, a signal output end of the oxygen sensor 56 is connected to a signal input end of the control device 7, and the oxygen sensor 56 is used to detect an oxygen content signal in the exhaust gas of the fuel engine.

[0054] In this embodiment, the signal detection module 5 detects the oxygen content in the exhaust gas of the engine by setting up an oxygen sensor 56. The control device 7 can calculate the carbon monoxide content in the exhaust gas based on this, so as to determine the combustion condition of the fuel in the engine. The control device 7 can control the opening of the throttle valve to adjust the air-fuel ratio according to the oxygen content signal in the exhaust gas of the fuel engine detected, thereby improving the working efficiency of the engine and further achieving energy conservation and emission reduction.

[0055] In one embodiment, the gas supply electric control valve 4 is a high-speed solenoid valve.

[0056] The high-speed solenoid valve has a very fast response time and can complete the valve opening and closing operation within milliseconds. This fast response characteristic enables the high-speed solenoid valve to achieve high-frequency switching and precise flow control. The control device 7 can control the opening and closing time of the high-speed solenoid valve through a PWM signal, thereby more accurately realizing the injection time and amount of gas fuel, and improving the combustion efficiency and power output of the engine.

[0057] In one embodiment, the ignition device 6 includes an igniter 61 and an ignition coil 62 . The signal input end of the igniter 61 is connected to the signal output end of the control device 7 , and the signal output end of the igniter 61 is connected to the signal input end of the ignition coil 62 .

[0058] In this embodiment, the igniter 61 is responsible for controlling the working state of the ignition coil 62. It determines when to generate high voltage electricity by controlling the on and off of the current, thereby controlling the ignition timing of the spark plug. The main function of the ignition coil 62 is to convert the low voltage provided by the power supply into a high voltage. This high voltage electricity will be guided to the spark plug to generate sparks to ignite the air and fuel mixture of the engine.

[0059] In one embodiment, the control device 7 is integrated into an inverter controller of a multi-fuel generator set.

[0060] In a multi-fuel generator set, the inverter controller is the main control component of the generator set, controlling the working status of the engine and the generator. In this embodiment, by integrating the control device 7 into the inverter controller of the multi-fuel generator set, centralized control is achieved while effectively reducing the wiring of the control system.

[0061] In some other embodiments, the control device 7 may also be an engine ECU or an independent control device.

[0062] An embodiment of the present invention further provides a generator set, which includes the multi-fuel generator set control system in any of the above embodiments.

[0063] The working principle of the generator set in this embodiment is the same as the working principle of the multi-fuel generator set control system in the above embodiment, and will not be repeated here. Since the generator set in this embodiment adopts the multi-fuel generator set control system in the above embodiment, the generator set has the same beneficial effects as the multi-fuel generator set control system, and can also actively control the supply of gas fuel and the ignition of the engine according to the real-time state of the engine, thereby effectively improving the engine starting performance of the multi-fuel generator set when using gas fuel and the working stability of the multi-fuel generator set.

[0064] Specifically, the generator set in this embodiment is a gas-liquid mixed three-fuel generator set using LPG, NG and gasoline as fuel.

[0065] like Figure 2 As shown, an embodiment of the present invention further provides a control method for any of the above-mentioned multi-fuel generator set control systems, and the control method may include the following steps:

[0066] S1, detecting a working state signal of a multi-fuel engine through a signal detection module and sending the signal to a control device, wherein the working state signal at least includes an engine start signal, a fuel type signal, an engine speed signal and a power generation signal;

[0067] S2, controlling the switch state of the gas supply electric control valve and the ignition time of the ignition device according to the received working state signal through the control device.

[0068] By adopting the control method of the multi-fuel generator set control system of this embodiment, when the multi-fuel generator set is started or operates normally, the status signals of the fuel switching switch and the engine start switch, i.e., the fuel type signal and the engine start signal, are detected by the signal detection module, and the engine working status signals such as the engine speed signal and the power generation signal are detected, and the detected working status signals are sent to the control device. The control device controls the switching state of the gas supply electric control valve and the ignition timing of the ignition device according to the received working status signal, thereby realizing active control of the engine gas supply and precise control of the engine ignition timing.

[0069] The control method of the multi-fuel generator set control system of this embodiment can actively control the supply of gas fuel and accurately control the ignition timing of the engine according to the real-time status of the engine. When the engine starts, the intake amount of gas fuel is no longer determined by the engine negative pressure, which effectively avoids the problem of inconsistent gas fuel intake amount at the same speed. It can effectively improve the engine starting performance of the multi-fuel generator set when using gas fuel and the working stability of the multi-fuel generator set, and achieve the effect of energy saving and emission reduction.

[0070] In one embodiment, in step S2, controlling the switch state of the gas supply electric control valve and the ignition time of the ignition device according to the received working state signal by the control device includes:

[0071] S21, when the fuel type signal indicates that the currently selected engine fuel is gas fuel, searching for an injection pulse width calibration table and an ignition advance angle calibration table corresponding to the fuel type signal in a preset engine control parameter database according to the fuel type signal, wherein the engine control parameter database stores a plurality of injection pulse width calibration tables and ignition advance angle calibration tables of different fuel types, each injection pulse width calibration table is provided with an injection pulse width corresponding to different engine speeds and power generation, and each ignition advance angle calibration table is provided with an ignition advance angle corresponding to different engine speeds and power generation;

[0072] Specifically, the jet pulse width calibration table and the ignition advance angle calibration table can be calibrated according to experiments before the generator set leaves the factory and stored in the engine control parameter database in the engine control unit.

[0073] Specifically, in the engine control parameter database, for the gas fuel used by the generator set, each gas fuel has an injection pulse width calibration table and an ignition advance angle calibration table stored, wherein:

[0074] As shown in Table 1, it is the jet pulse width calibration table of NG. The data in the first row of the jet pulse width calibration table represents the engine speed (in r / min), the data in the first column represents the power generated by the generator set (in W), and the data in the remaining grids represent the jet pulse width (in ms) corresponding to each speed and power (i.e., the pulse width of the PWM signal output by the control device to control the gas supply electric control valve);

[0075] As shown in Table 2, this is the ignition advance angle calibration table for NG. The data in the first row of the ignition advance angle calibration table represents the engine speed, the data in the first column represents the power generation of the generator set, and the data in the remaining grids represent the ignition advance angle (in degrees) of the ignition device corresponding to each speed and power.

[0076] For example, when the fuel type signal indicates that the currently selected engine fuel is NG, the jet pulse width calibration table and ignition advance angle calibration table corresponding to the fuel type signal are searched in the preset engine control parameter database according to the fuel type signal, which are Table 1 and Table 2 respectively.

[0077] Table 1: NG jet pulse width calibration table

[0078]

[0079]

[0080] Table 2: NG ignition advance angle calibration table

[0081]

[0082] S22, searching for an injection pulse width that matches the engine speed signal and the power generation signal in the injection pulse width calibration table based on the engine speed signal and the power generation signal, and searching for an ignition advance angle that matches the engine speed signal and the power generation signal in the ignition advance angle calibration table based on the engine speed signal and the power generation signal;

[0083] For example, in Table 1, when the engine speed is 2000r / min and the power generation is 4500W, the corresponding jet pulse width is 20.125ms; in Table 2, when the engine speed is 2000r / min and the power generation is 4500W, the corresponding ignition advance angle is 15.00°.

[0084] S23, generating a corresponding PWM control signal based on the found jet pulse width, and generating a corresponding ignition control signal based on the found ignition advance angle;

[0085] The duty cycle of the PWM signal can be calculated through the jet pulse width, and the ignition timing of the ignition device can be calculated through the ignition advance angle. Therefore, after finding the jet pulse width and ignition advance angle corresponding to the current fuel, current speed and current power generation power, the corresponding PWM control signal can be generated based on the jet pulse width found, and the corresponding ignition control signal can be generated based on the ignition advance angle found.

[0086] S24, controlling the switch state of the gas supply electric control valve based on the PWM control signal, and controlling the ignition timing of the ignition device based on the ignition control signal.

[0087] Finally, the switching state of the gas supply electronic control valve can be controlled according to the generated PWM control signal, thereby controlling the intake amount of gas fuel, and the ignition timing of the ignition device can be controlled according to the generated ignition control signal, thereby accurately controlling the ignition timing. The combination of the two can effectively ensure that the engine operates in the best working conditions.

[0088] In this embodiment, the optimal operating parameters of the engine are matched by the above-mentioned table lookup method, so that the internal operation process of the program when the engine is started and during the operation of the engine is simpler, and the matching efficiency and matching accuracy between the current operating state parameters of the engine and the control parameters of the engine are higher.

[0089] In addition, a corresponding jet pulse width calibration table and ignition advance angle calibration table are set for each gas fuel, so that the engine control parameters between various gas fuels have obvious independence. In the subsequent use process or for different engine products, when it is necessary to increase the engine control parameters of different fuels, the incremental cost involved in adding the jet pulse width calibration table and the ignition advance angle calibration table separately is relatively small. In addition, when the control program during engine startup and operation is upgraded by modifying the control parameters in the corresponding jet pulse width calibration table and the ignition advance angle calibration table, each jet pulse width calibration table and the ignition advance angle calibration table can be optimized separately without affecting the normal use of other jet pulse width calibration tables and the ignition advance angle calibration tables.

[0090] It should be noted that, due to limited space, the jet pulse width calibration table shown in Table 1 and the ignition advance angle calibration table shown in Table 2 only show some of the jet pulse width and ignition advance angle data corresponding to the engine speed and power generation. In actual application, the data points of the engine speed and power generation can be more dense. For example, a data point can be set for every 100 r / min of engine speed, and a data point can be set for every 100 W of power generation. When the actual data of the detected engine speed and power generation deviate from the data points in the table, the data corresponding to the data point closest to the calibrated data point in the table is used. For example, when the detected engine speed is 2465 r / min and the power generation is 2123 W, the jet pulse width corresponding to the engine speed of 2500 r / min and the power generation of 2100 W is selected in the jet pulse width calibration table.

[0091] It can be understood that the denser the data points in Table 1 and Table 2, the more accurate the injection pulse width and ignition advance angle data obtained by looking up the table.

[0092] In one embodiment, since the operating efficiency of the generator set is optimized at different temperatures, the optimal supply amount of gas fuel required for engine startup and normal operation at the same power and speed is also different. When the power and speed are constant, the efficiency of the engine is low when the engine is cold. In order to keep the operating efficiency of the multi-fuel engine optimal at different temperatures, based on the previous embodiment, the injection amount of the gas fuel can be further compensated according to the cylinder temperature of the engine. Therefore, the control method provided by this embodiment can include the following steps:

[0093] S1', detecting the working state signal of the multi-fuel engine through the signal detection module and sending it to the control device, wherein the working state signal at least includes an engine start signal, a fuel type signal, an engine speed signal, a power generation signal and a cylinder temperature signal;

[0094] S2', the control device controls the switch state of the gas supply electric control valve and the ignition time of the ignition device according to the received working state signal. The specific process is as follows

[0095] S21', when the fuel type signal indicates that the currently selected engine fuel is gas fuel, the jet pulse width calibration table, the ignition advance angle calibration table and the jet compensation amount calibration table corresponding to the fuel type signal are searched in the preset engine control parameter database according to the fuel type signal, wherein the engine control parameter database stores a plurality of jet pulse width calibration tables, ignition advance angle calibration tables and jet compensation amount calibration tables of different fuel types, each jet pulse width calibration table is provided with jet pulse widths corresponding to different engine speeds and power generation, each ignition advance angle calibration table is provided with ignition advance angles corresponding to different engine speeds and power generation, and each jet compensation amount calibration table is provided with jet pulse width compensation coefficients corresponding to different power generation and cylinder body temperature;

[0096] S22', searching the jet pulse width calibration table for the jet pulse width that matches the engine speed signal and the power generation signal based on the engine speed signal and the power generation signal, and searching the ignition advance angle calibration table for the ignition advance angle that matches the engine speed signal and the power generation signal based on the engine speed signal and the power generation signal;

[0097] For example, in Table 1, when the engine speed is 2000r / min and the power generation is 4500W, the corresponding jet pulse width is 20.125ms; in Table 2, when the engine speed is 2000r / min and the power generation is 4500W, the corresponding ignition advance angle is 15.00°.

[0098] S23', searching the jet pulse width compensation coefficient that matches the power generation signal and the cylinder temperature signal in the jet compensation calibration table obtained based on the power generation signal and the cylinder temperature signal;

[0099] As shown in Table 3, it is the jet compensation calibration table of NG. The data in the first row of the jet compensation calibration table represents the cylinder temperature of the engine (in °C), the data in the first column represents the power generation of the generator set, and the data in the remaining grids represent the jet pulse width compensation coefficient corresponding to each temperature and power. For example, in Table 3, when the cylinder temperature of the engine is -20 °C and the power generation is 4500W, the corresponding jet pulse width compensation coefficient is 11.00.

[0100] When the fuel type signal indicates that the currently selected engine fuel is NG, the jet pulse width calibration table, ignition advance angle calibration table and jet compensation amount calibration table corresponding to the fuel type signal are searched in the preset engine control parameter database according to the fuel type signal, which are Table 1, Table 2 and Table 3 respectively.

[0101] Table 3: NG jet compensation calibration table

[0102]

[0103] S24', obtain the jet pulse width after temperature compensation by looking up the table to obtain the jet pulse width that matches the engine speed signal and the power generation signal, and the jet pulse width compensation coefficient that matches the power generation signal and the cylinder temperature signal; that is, the jet pulse width that matches the engine speed signal and the power generation signal obtained by looking up the table and the jet pulse width compensation coefficient that matches the power generation signal and the cylinder temperature signal obtained by looking up the table are calculated according to a preset rule (in this embodiment, the product of the jet pulse width and the jet pulse width compensation coefficient is divided by 10), so as to obtain the jet pulse width after temperature compensation.

[0104] S25', generating a corresponding PWM control signal based on the temperature-compensated jet pulse width obtained by calculation, and generating a corresponding ignition control signal based on the ignition advance angle obtained by searching;

[0105] The duty cycle of the PWM signal can be calculated through the temperature-compensated injection pulse width, and the ignition timing of the ignition device can be calculated through the ignition advance angle.

[0106] S26', controlling the switch state of the gas supply electric control valve based on the generated PWM control signal, and controlling the ignition timing of the ignition device based on the generated ignition control signal.

[0107] Since different temperatures and different fuel types require different amounts of air to optimize the combustion efficiency of gaseous fuel, in order to optimize the combustion efficiency of the multi-fuel engine at different temperatures, in one embodiment, the control method of the present invention may further include the following steps:

[0108] The cylinder temperature signal of the multi-fuel engine is detected by the signal detection module and sent to the control device;

[0109] The throttle opening of the carburetor is controlled by the control device according to the cylinder temperature signal and the fuel type signal received. The specific process is as follows:

[0110] According to the received cylinder temperature signal and fuel type signal, searching the throttle opening calibration table in the preset engine control parameter database for throttle opening information matching the received cylinder temperature signal and fuel type signal;

[0111] Generate a corresponding throttle control signal based on the throttle opening information found;

[0112] The opening degree of the throttle valve of the carburetor is controlled based on the generated throttle valve control signal.

[0113] Specifically, the throttle opening calibration table is shown in Table 4:

[0114] Table 4: Throttle opening calibration table

[0115]

[0116] The data in the first row of the throttle opening calibration table represents the engine cylinder temperature (in degrees Celsius), the data in the first column represents the fuel type, and the data in the remaining grids represent the throttle opening data of the carburetor corresponding to each temperature and fuel type. It should be noted that the throttle opening data in the table is not the actual throttle opening, but the opening coefficient that is positively correlated with the throttle opening.

[0117] In order to improve the success rate of the first start of the engine, the gas supply electronic control valve can be opened in advance to pre-spray part of the gas fuel into the engine cylinder when the engine is started, so as to achieve the enrichment of the gas fuel in the engine cylinder. Since the amount of gas fuel required to optimize the success rate of the first start of the engine under different temperatures and different fuel types is also different, therefore, in order to maintain the best success rate of the first start of the multi-fuel engine under different temperatures, in one embodiment, the control method of the present invention can also include the following steps:

[0118] The cylinder temperature signal of the multi-fuel engine is detected by the signal detection module and sent to the control device;

[0119] The control device controls the pre-injection opening time of the gas supply electric control valve according to the received cylinder temperature signal and fuel type signal. The specific process is as follows:

[0120] Searching for pilot injection time information matching the received cylinder temperature signal and fuel type signal in a pilot injection time calibration table in a preset engine control parameter database according to the received cylinder temperature signal and fuel type signal;

[0121] Generate a corresponding pre-spray control signal based on the pre-spray time information found;

[0122] The pilot injection opening time of the gas supply electric control valve is controlled based on the generated pilot injection control signal.

[0123] Specifically, the pre-spray time calibration table is shown in Table 5:

[0124] Table 5: Pre-spray time calibration table

[0125]

[0126] The data in the first row of the pilot injection time calibration table represents the engine cylinder temperature (in °C), the data in the first column represents the fuel type, and the data in the remaining grids represents the pilot injection opening time (in ms) of the gas supply electronic control valve corresponding to each temperature and fuel type.

[0127] The present invention implements all or part of the processes in the control method of the multi-fuel generator control system of the above embodiment, which can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, the steps of each of the above method embodiments can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device that can carry the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electric carrier signal, telecommunication signal and software distribution medium. It should be noted that the content contained in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electric carrier signals and telecommunication signals.

[0128] Those skilled in the art will appreciate that, although some embodiments herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present invention and form different embodiments. For example, in the claims below, any one of the claimed embodiments may be used in any combination.

[0129] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A control system for a multi-fuel generator set, the multi-fuel generator set comprising a multi-fuel engine and a generator drivingly connected to the multi-fuel engine, characterized in that: The control system includes a fuel switching switch, an engine start switch, a carburetor, a gas supply electric control valve, a signal detection module, an ignition device and a control device. The gas fuel supply pipeline of the multi-fuel engine is connected to the air inlet of the gas supply electric control valve, and the air outlet of the gas supply electric control valve is connected to the gas fuel inlet of the carburetor. The fuel switching switch and the engine start switch are respectively connected to the signal detection module, and the carburetor, the gas supply electric control valve, the signal detection module and the ignition device are respectively connected to the control device, wherein: The signal detection module is used to detect the working state signal of the multi-fuel engine and send the detected working state signal to the control device; The control device is used to control the switch state of the gas supply electric control valve and the ignition timing of the ignition device according to the received working state signal.

2. The multi-fuel generator set control system according to claim 1, characterized in that: The signal detection module includes an engine start signal detection circuit, a fuel type detection circuit, a speed sensor and a power detection circuit. The signal output ends of the engine start signal detection circuit, the fuel type detection circuit, the speed sensor and the power detection circuit are respectively connected to the signal input ends of the control device. The signal input end of the engine start signal detection circuit is connected to the engine start switch. The signal input end of the fuel type detection circuit is connected to the fuel switching switch. The engine start signal detection circuit is used to detect the state of the engine start switch and output an engine start signal when the engine start switch is in the on state; The fuel type detection circuit is used to detect the state of the fuel switching switch and output a corresponding fuel type signal; The rotation speed sensor is used to detect the rotation speed signal of the fuel engine; The power detection circuit is used to detect the current signal of the main winding of the generator and convert the current signal into a power generation signal.

3. The multi-fuel generator set control system according to claim 2, characterized in that: The signal detection module further includes a temperature sensor, a signal output end of the temperature sensor is connected to a signal input end of the control device, and the temperature sensor is used to detect a cylinder temperature signal of the fuel engine.

4. The multi-fuel generator set control system according to claim 2, characterized in that: The signal detection module further comprises an oxygen sensor, a signal output end of the oxygen sensor is connected to a signal input end of the control device, and the oxygen sensor is used to detect an oxygen content signal in the exhaust gas of the fuel engine.

5. The multi-fuel generator set control system according to claim 1, characterized in that: The gas supply electric control valve is a high-speed solenoid valve.

6. The multi-fuel generator set control system according to claim 1, characterized in that: The ignition device comprises an igniter and an ignition coil. The signal input end of the igniter is connected to the signal output end of the control device, and the signal output end of the igniter is connected to the signal input end of the ignition coil.

7. The multi-fuel generator set control system according to any one of claims 1 to 6, characterized in that: The control device is integrated in the inverter controller of the multi-fuel generator set.

8. A generator set, characterized in that: The generator set comprises a multi-fuel generator set control system as described in any one of claims 1-7.

9. A control method for a multi-fuel generator set control system according to any one of claims 1 to 7, characterized in that: The control method comprises the following steps: S1, detecting the working state signal of the multi-fuel engine through the signal detection module and sending it to the control device, wherein the working state signal at least includes an engine start signal, a fuel type signal, an engine speed signal and a power generation signal; S2, controlling the switch state of the gas supply electric control valve and the ignition timing of the ignition device according to the received working state signal by the control device.

10. The control method of the fuel generator set control system according to claim 9, characterized in that: In step S2, the control device controls the switch state of the gas supply electric control valve and the ignition time of the ignition device according to the received working state signal, including: S21, when the fuel type signal indicates that the currently selected engine fuel is gas fuel, searching for an injection pulse width calibration table and an ignition advance angle calibration table corresponding to the fuel type signal in a preset engine control parameter database according to the fuel type signal, wherein the engine control parameter database stores a plurality of injection pulse width calibration tables and ignition advance angle calibration tables of different fuel types, each of the injection pulse width calibration tables is provided with an injection pulse width corresponding to different engine speeds and power generation, and each of the ignition advance angle calibration tables is provided with an ignition advance angle corresponding to different engine speeds and power generation; S22, searching for an injection pulse width matching the engine speed signal and the power generation signal in the injection pulse width calibration table based on the engine speed signal and the power generation signal, and searching for an ignition advance angle matching the engine speed signal and the power generation signal in the ignition advance angle calibration table based on the engine speed signal and the power generation signal; S23, generating a corresponding PWM control signal based on the jet pulse width obtained by searching, and generating a corresponding ignition control signal based on the ignition advance angle obtained by searching; S24, controlling the switch state of the gas supply electric control valve based on the PWM control signal, and controlling the ignition timing of the ignition device based on the ignition control signal.

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