A gas rail heating control method, system, and range-extended vehicle

Abstract

This application provides a gas rail heating control method, system, and range-extended vehicle in the field of cold start technology. During initial power-on or driving cycle, the gas rail temperature is acquired. When the gas rail temperature is below a first temperature threshold, a start-prohibited state bit is set, and gas rail heating is initiated, while a heating status flag is set. The start-prohibited state bit indicates that the VCU (Vehicle Control Unit) is prohibited from sending start requests to the EMS (Electrical Management System). When the gas rail temperature reaches a second temperature threshold, gas rail heating is stopped, and the start-prohibited state bit is cleared to restore the EMS's start response. The solution provided in this application has the advantage of effectively solving the ice blockage problem.

Description

Technical Field

[0001] This application relates to the field of cold start technology, and more specifically, to a gas rail heating control method, system, and range-extended vehicle. Background Technology

[0002] In range-extended electric vehicles, the engine, acting as a range extender, typically uses natural gas (CNG / LNG) or liquefied petroleum gas (LPG) as fuel. The fuel gas needs to be depressurized and vaporized before entering the engine cylinders for combustion. A key component in its supply path, the fuel rail, is responsible for stabilizing pressure, equalizing flow, and distributing fuel gas to the injectors in each cylinder. However, the fuel gas exhibits a significant Joule-Thomson cooling effect during depressurization and expansion, especially in low-temperature environments (such as below -15°C in winter) or during the initial cold start. The temperature of the fuel rail body can easily drop sharply below -15°C, leading to poor fuel atomization and abnormal phase change. Specifically, the low temperature causes insufficient vaporization of the fuel gas (especially natural gas components), easily forming liquid residue or ice blockage within the fuel rail, resulting in inaccurate injection pulse width and uncontrolled air-fuel ratio.

[0003] Currently, the conventional solution to this problem is to use fuel-assisted starting, and then switch to natural gas combustion for power after the engine has warmed up. However, this solution requires two sets of systems on the engine (natural gas rail / injector and fuel rail / injector), which significantly increases engine cost and layout complexity. Furthermore, range extenders using only gaseous fuels cannot effectively solve the "ice blockage" problem. Summary of the Invention

[0004] The purpose of this application is to provide a gas rail heating control method, system, and range-extended vehicle to solve the ice blockage problem existing in the single gas fuel range extender in the prior art.

[0005] To achieve the above objectives, the technical solutions adopted in the embodiments of this application are as follows: In a first aspect, embodiments of this application provide a gas rail heating control method applied to an EMS, the method comprising: During the first power-on or driving cycle, the gas rail temperature is acquired. When the gas rail temperature is lower than the first temperature threshold, the start-prohibited state bit is set, and gas rail heating is started, and the heating status flag bit is set. The start-prohibited state bit indicates that the VCU is prohibited from sending a start request to the EMS. When the gas rail temperature is heated to the second temperature threshold, heating of the gas rail is stopped, and the start-prohibited state bit is cleared to restore the EMS start-up response.

[0006] Optionally, after clearing the disabled startup status bit, the method further includes: The decision to restart the gas rail heating depends on the status of the range extender and the temperature of the gas rail.

[0007] Optionally, the step of determining whether to restart the gas rail heating based on the range extender's status and the gas rail temperature includes: When the range extender is in operation, the gas rail heating is not activated; When the range extender is in a stopped state and the gas rail temperature is lower than the first temperature threshold, the start-prohibited state position is set again, and the gas rail heating is started until the gas rail temperature is heated to the second temperature threshold.

[0008] Optionally, the steps to initiate the heating of the gas rail include: Control the relay to close, thereby initiating the heating of the gas rail; The steps to stop heating the gas rail include: The control relay is disconnected to stop heating the gas rail.

[0009] Optionally, the VCU's prohibition of sending startup requests to the EMS includes: The EMS sends a boot-prohibited status bit to the VCU, so that the VCU is prohibited from sending boot requests.

[0010] Optionally, the first temperature threshold ranges from -30℃ to -10℃; the second temperature threshold ranges from -5℃ to 0℃.

[0011] Optionally, the first temperature threshold is set to -15℃; the second temperature threshold is set to 0℃.

[0012] Optionally, the criteria for determining the first power-on are as follows: The entire vehicle's KL15 is powered on and the high voltage is on, and the engine status flag is in the off state.

[0013] Secondly, embodiments of this application also provide a gas rail heating control system for executing the above-described gas rail heating control method, the system comprising: Temperature monitoring module, used to monitor the gas rail temperature in real time; A heating execution module is used to heat the gas rail during startup; EMS is connected to the temperature monitoring module and the heating execution module, and is used to generate and manage the prohibited start status bit and the heating status flag bit.

[0014] Thirdly, embodiments of this application also provide a range-extended vehicle, the range-extended vehicle including an EMS, a VCU, a GCU, and a gas rail, wherein the EMS is configured to perform the above-described method to achieve active heating control of the gas rail.

[0015] The range-extended vehicle is a single-fuel vehicle, and the single fuel includes natural gas and methanol.

[0016] Compared with the prior art, the embodiments of this application have the following beneficial effects: This application provides a gas rail heating control method, system, and range-extended vehicle. During the initial power-on or driving cycle, the gas rail temperature is acquired. When the gas rail temperature is lower than a first temperature threshold, a start-prohibited state bit is set, and gas rail heating is initiated, while a heating status flag bit is set. The start-prohibited state bit indicates that the VCU is prohibited from sending a start request to the EMS. When the gas rail temperature is heated to a second temperature threshold, gas rail heating is stopped, and the start-prohibited state bit is cleared to restore the EMS's start response.

[0017] The control method provided in this application defines a start-prohibition state bit and a heating state flag bit, which serve as the basis for communication and decision-making between the EMS and VCU (vehicle control unit). This ensures a strict logical sequence between the heating process and the vehicle start command, preventing damage caused by forced start-up before ice blockage is resolved. Therefore, even for range extenders using a single gas fuel, the ice blockage problem can be solved.

[0018] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is an exemplary flowchart of a gas rail heating control method provided in an embodiment of this application. Figure 2 This is a circuit diagram of the heating execution module provided in an embodiment of this application.

[0021] Figure 3 A timing diagram of the heating control signal provided in an embodiment of this application.

[0022] Figure 4 This is a schematic diagram of the -15℃ air rail temperature start-up data provided in the embodiments of this application.

[0023] Figure 5A schematic diagram of the gas rail heating control system provided in an embodiment of this application.

[0024] In the picture: 110 - EMS; 120 - Temperature monitoring module; 130 - Heating execution module. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0027] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this application, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0028] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Some embodiments of this application are described in detail below with reference to the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0029] As described in the background section, in gas-powered range extender systems, the lack of gasoline-assisted starting and the tendency of moisture in natural gas and oil contamination introduced from gas stations to condense at low temperatures can lead to ice blockage in the injection rail and nozzles. When the gas rail temperature drops to -15°C or below, fuel cannot be injected normally, resulting in starting failure, unstable combustion, and worsened emissions, severely impacting the user experience and reliability in cold regions.

[0030] The existing technology uses a coolant-heated gas rail solution, which uses the engine coolant circulation to exchange heat through the gas rail structure that wraps the gas duct, thereby passively heating the gas. This solution aims to utilize the engine's waste heat and has a low cost. However, this solution is not suitable for the first power-on.

[0031] For example, in dual-fuel systems (i.e., both gasoline and gas fuel), heating primarily serves to facilitate smooth switching between fuel modes and is an auxiliary function. It relies entirely on the residual heat from the coolant generated after the engine has started. When the range extender is not activated, there is no heat source, and pre-heating or independent heating is impossible. However, this method only applies to situations where the engine is already running (gasoline mode) and cannot solve the fundamental problem of cold engine start-up. Furthermore, this method is not suitable for applications based on a single gas fuel range extender.

[0032] In view of this, in order to solve the above problems, this application provides a gas rail heating control method, please refer to... Figure 1 The method includes: S102, during the first power-on or driving cycle, obtain the gas rail temperature. When the gas rail temperature is lower than the first temperature threshold, set the start-prohibited state bit and start heating the gas rail, and set the heating state flag bit. The start-prohibited state bit indicates that the VCU is prohibited from sending a start request to the EMS.

[0033] S104, when the gas rail temperature is heated to the second temperature threshold, stop heating the gas rail and clear the start-prohibited status bit to restore the EMS start response.

[0034] Understandably, this application treats the gas rail itself as the direct heating object, i.e., it adopts active heating. Furthermore, it utilizes a closed-loop temperature control range formed by a first temperature threshold and a second temperature threshold, and relies on a start-prohibited state bit and a heating state flag bit to achieve a safety interlock between the EMS (Engine Management System) and the VCU (Vehicle Control Unit). This ensures that the VCU can only send a start request to the EMS after the gas rail temperature returns to a safe range. During heating, the VCU is prohibited from sending start requests to the EMS, thus fundamentally avoiding the risk of start-up failure or abnormal engine operation caused by low-temperature ice blockage, and realizing the start-up of a single fuel range extender at low temperatures.

[0035] It should be noted that traditional engine low-temperature start-up assistance technologies, such as intake air preheating or coolant heating, mainly act on the macroscopic combustion environment inside the engine cylinder. Their heat transfer paths are long, their response is slow, and their targeting is weak. They are almost ineffective in addressing the blockage caused by trace amounts of moisture or heavy hydrocarbon impurities in the fuel gas freezing within the precision channels of the nozzles. This situation means that in extremely cold environments, even if all other engine conditions meet the starting requirements, the fuel gas may still not be injected stably due to partial or complete blockage of the nozzles by ice crystals, leading to fluctuations in engine speed, insufficient torque, or even start-up failure.

[0036] Based on this, the technical solution adopted in this application, with the EMS as the implementing entity, can acquire the gas rail temperature during the initial power-on or driving cycle. When this temperature is lower than a first temperature threshold, it sets a start-prohibited state bit (EMS_Banstart_Vaild=1), simultaneously initiating gas rail heating and setting a heating status flag bit (Heating status=1). When the gas rail temperature is heated to a second temperature threshold, the EMS can stop heating the gas rail and clear the start-prohibited state bit (EMS_Banstart_Vaild=0) to restore the EMS's start-up response.

[0037] The control mechanism focuses primarily on the gas rail and nozzle components, achieving control objectives through two temperature parameters. The first temperature threshold is set based on the freezing temperature curves of common impurities in the gas (especially water vapor) and ambient temperature changes. For example, it's based on the freezing characteristics of water vapor and heavy hydrocarbon impurities in the gas. When the temperature falls below this threshold, the risk of trace amounts of water in the gas freezing and adhering to the precision channels of the nozzle increases dramatically. Simultaneously, trace amounts of heavy hydrocarbons that may precipitate from natural gas at low temperatures can exacerbate blockage. The second temperature threshold is set to the freezing point of water, ensuring that the temperature inside the gas rail and the nozzle area remains stable above this value, fundamentally eliminating the physical conditions for ice blockage. Furthermore, this threshold provides a favorable temperature environment for gas vaporization and stable flow. Therefore, ensuring that the temperature inside the gas rail and the nozzle area remains consistently above freezing conditions completely eliminates the possibility of ice blockage. This design ensures safe startup while also considering energy efficiency, avoiding unnecessary heating in risk-free temperature ranges.

[0038] As one implementation method, the first temperature threshold can be calibrated and optimized based on the gas source quality (such as moisture content), the gas rail material, and low-temperature cold immersion test data of a specific vehicle model. Its adjustable range is typically -30℃ to -10℃. The second temperature threshold can be fine-tuned in conjunction with the waste heat recovery capability after engine startup. For example, if the system can quickly utilize engine waste heat to maintain the gas rail temperature, the electric heating stop threshold can be appropriately lowered to the range of -5℃ to 0℃ to shorten the electric heating time. For example, the first temperature threshold is set to -30℃, -15℃, or -100℃, and the second temperature threshold is set to 0℃ or -5℃.

[0039] Furthermore, the EMS not only performs temperature judgment and heating start / stop actions, but also uses the prohibition-start status bit and heating status flag bit as the core communication basis for cooperating with the VCU. For example, during heating, the EMS continuously maintains the prohibition-start status bit as valid, preventing the VCU from sending start requests to the EMS; only when the EMS confirms that the gas rail temperature has reached the second temperature threshold, heating is complete, and the prohibition-start status bit is cleared, is the VCU allowed to send a drag command to the GCU (Generator Controller) to start the engine. This status flag-based collaborative management mechanism embeds the heating process into the front end of the vehicle's starting logic chain, forming strict timing constraints and safety interlocks, effectively preventing the risk of starting with ice caused by user misoperation or system mis-triggering.

[0040] In addition, EMS can accurately identify the initial power-on time of the vehicle in a cold state based on the combination of the vehicle's KL15 being powered on and the high voltage being powered on, while the engine status flag is in a stopped state. Thus, it can proactively start the preheating process before the user issues any operation commands, significantly improving the start-up reliability of the vehicle for the first time in extremely cold regions.

[0041] It should be noted that the power-on mentioned in this application refers to the situation where the vehicle power is switched from off to starting. The driving cycle mentioned in this application may refer to a certain time period after the vehicle is started, or each start and stop during vehicle operation constitutes a driving cycle, and is not limited here.

[0042] As can be seen, this application achieves the prevention and control of the specific failure mode of gas nozzle ice blockage by real-time monitoring of gas rail temperature through EMS, precise application of two temperature thresholds, coordinated management of start-prohibited status and heating status flags, and identification and response to the critical state of first power-on, thus enabling the vehicle to have stable, safe and reliable gas start-up capability under severe cold conditions.

[0043] As one implementation, after step S104, the method further includes: S106 determines whether to restart the gas rail heating based on the status of the range extender and the gas rail temperature.

[0044] Understandably, after the EMS completes its initial power-on, clears the start-prohibited status bit, and resumes its ability to respond to the start request from the VCU (Vehicle Control Unit), the EMS does not terminate its thermal management responsibilities. Instead, it continuously monitors the operating status of the range extender (i.e., the generator control unit, GCU) and the gas rail temperature, and autonomously decides whether to restart the gas rail heating based on the combination of these two conditions.

[0045] When the range extender is running, the EMS can choose not to start heating the gas rail; when the range extender is stopped and the gas rail temperature is lower than the first temperature threshold, the EMS can set the start-prohibited state again and start heating the gas rail until the gas rail temperature is heated to the second temperature threshold.

[0046] When the vehicle is running, the EMS will check the status of the range extender and obtain the gas rail temperature in each driving cycle. If the range extender is running, it means that the vehicle is still in use and does not need to be heated. If the range extender is stopped and the gas rail temperature is below the first temperature threshold, the vehicle may be parked. In this case, when a valid start command is received from the VCU, heating will be restarted.

[0047] Furthermore, the gas rail heating control system includes a heating execution module and a temperature monitoring module, with the EMS connected to both. The heating execution module includes a relay and a heating element, connected to both. The relay's control terminal is connected to the EMS. The EMS can initiate gas rail heating by closing the relay and stop heating by opening the relay. In one implementation, please refer to [link to implementation details]. Figure 2 The heating execution module may also include a main relay and a heating control relay, with the main relay and the heating control relay connected together, and the EMS connected to both the main relay and the heating control relay.

[0048] Furthermore, the VCU described in this application prohibits sending startup requests to the EMS. Specifically, the EMS can send a startup-prohibited status bit to the VCU, so that the VCU is prohibited from sending startup requests. This method enables the VCU to prevent the sending of startup requests from the source after receiving the signal, thus forming upstream interception.

[0049] It should be noted that in existing technologies, natural gas vehicles typically only perform gas rail heating once when the vehicle is first powered on. Once heating is complete and the engine starts successfully, the system does not intervene further, regardless of whether the range extender stops or how much the gas rail temperature drops. This static control mode ignores the dynamic nature of actual driving scenarios. In a driving cycle, when the range extender shuts down due to sufficient power or operational adjustments, the engine stops running, the gas rail loses its residual heat supply, and its temperature continues to drop with the environment. If the air temperature is extremely low at this time, the gas rail temperature may drop below freezing again, causing the nozzles to freeze and become clogged again. Because the system lacks a secondary heating trigger mechanism, when the driver attempts to start the vehicle again, the EMS will still respond to the VCU's start request, but the result will be start failure, engine speed fluctuations, or abnormal torque due to nozzle icing.

[0050] In this application, the gas rail heating is upgraded from a one-time cold preheating to an on-demand adaptive heat maintenance throughout the entire vehicle use process, thereby ensuring the vehicle's continuous starting reliability after multiple start-stop operations and long-term parking in extremely cold regions.

[0051] In practical applications, the EMS can accurately identify the initial power-on moment based on the vehicle's KL15 switch being turned on, the high-voltage system being powered on, and the engine status flag being in the off state. When the gas rail temperature is below the first temperature threshold (e.g., set to -15℃), it sets the start-prohibited state position, controls the gas rail relay to engage (i.e., activates the electronic switch of the heating circuit), and begins heating the gas rail. Simultaneously, it sets the heating status flag and illuminates the gas rail heating indicator on the vehicle's instrument panel, providing the user with intuitive feedback on the current status. During this process, the EMS continuously maintains the start-prohibited state position as valid, preventing the VCU from sending start requests to the EMS, thus preventing ice-based starts. When the gas rail temperature (i.e., the EMS Gastemperature) heats to the second temperature threshold (e.g., set to 0℃), the EMS can control the gas rail relay to disconnect, stopping heating, and simultaneously clear the start-prohibited state position, restoring the EMS's ability to respond to VCU start requests.

[0052] Furthermore, in the current driving cycle, after the initial heating of the gas rail, the gas rail temperature gradually increases as the engine runs. However, when the range extender enters the shutdown state, the engine stops working, the gas rail loses its heat source, and the temperature begins to drop. During this stage, the EMS continuously monitors the status of the range extender (i.e., whether the GCU is in generator operation) and the gas rail temperature: if the range extender is running, it indicates that the engine is working, the gas injectors are in normal injection conditions, and the gas rail temperature can be maintained by the engine's residual heat, so there is no need to restart the gas rail heating. If the range extender is shut down and the gas rail temperature drops to the first temperature threshold (e.g., -15°C), the EMS can re-set the start-prohibited state and, upon receiving a start request from the VCU, start the gas rail heating; otherwise, it will not start. This method ensures that heating is only activated when the range extender is shut down and the temperature has dropped to the high-risk icing range, avoiding both accidental heating that wastes electrical energy and missed heating that could lead to start-up failure.

[0053] As can be seen, this application achieves a paradigm shift in gas rail heating from single-cycle preheating to cyclic adaptive heating by jointly interpreting the range extender status and gas rail temperature through EMS, dynamically maintaining the start-prohibited status and heating status flags, precisely controlling the relay on / off states, and preventing the VCU from sending start requests to the EMS. This not only solves the risk of secondary ice blockage caused by range extender shutdown during driving cycles, but also deeply embeds thermal management into the vehicle's main control chain through status coordination and communication interlocking, significantly improving the vehicle's all-weather, high-frequency start-up safety and functional robustness in extremely cold environments.

[0054] In summary, combining Figure 3 and Figure 4 The gas rail heating control method provided in this application mainly includes the following steps: 1. Upon first power-on (KL15, HV=ON), with the engine status flag EMS_Engine Status=Stop and the gas rail temperature identified as being below -15℃, the EMS will send a start-prohibited status EMS_Banstart_Vaild=1 on the bus, and simultaneously control the gas rail relay to engage, starting the gas rail heating, and the gas rail heating light on the instrument panel will illuminate.

[0055] 2. During air rail heating, the heating status flag is set to 1, and the start-up status is disabled (EMS_Banstart_Vaild=1). The VCU is prohibited from sending start requests to the EMS.

[0056] 3. When the gas rail temperature is heated to 0℃ by the EMS, the EMS controls the gas rail relay to disconnect, stopping the gas rail heating and prohibiting the start status bit EMS_Banstart_Vaild=0.

[0057] 4. After the initial heating of the current driving cycle air rail is completed, the air rail temperature will gradually decrease as the engine runs. During this period, the range extender may be in one of two operating states: running or stopped. If the range extender is running and the gas injectors are working normally, heating is not required. If the range extender is stopped and the air rail temperature drops to -15℃, the start-prohibited flag EMS_Banstart_Vaild=1. The EMS will start air rail heating after receiving a VCU request Start=1; otherwise, heating will not begin.

[0058] 5. After the air rail heating is completed, the VCU receives the EMS status EMS_BanStart Valid=False and controls the GCU to start driving the engine and enter the start-up process. The EMS sends the start-up success flag EMS_StartSuccess=Success to the CAN according to its own status. After receiving the EMS start-up success flag, the VCU resets the start-up request VCU_Engine StartRequest=No Request. Thus, the CNG start-up under extreme cold conditions is completed.

[0059] Based on the above implementation method, please refer to Figure 5 This application also provides a gas rail heating control system for executing the above-described gas rail heating control method, the system comprising: Temperature monitoring module 120 is used to monitor the gas rail temperature in real time; Heating execution module 130 is used to heat the gas rail during startup; The EMS110 connects to the temperature monitoring module and the heating execution module, and is used to generate and manage the start-prohibited status bit and the heating status flag bit.

[0060] In addition, this application also provides a range-extended vehicle, which includes an EMS, a VCU, a GCU, and a gas rail, wherein the EMS is configured to perform the above-described method to achieve active heating control of the gas rail.

[0061] For example, the range-extended vehicle is a single-fuel vehicle, and the single fuel includes natural gas and methanol.

[0062] In summary, this application provides a gas rail heating control method, system, and range-extended vehicle. During initial power-on or a driving cycle, the gas rail temperature is acquired. When the gas rail temperature is below a first temperature threshold, a "prohibit start" state bit is set, and gas rail heating is initiated, while a heating status flag bit is set. The "prohibit start" state bit indicates that the VCU (Vehicle Control Unit) is prohibited from sending start requests to the EMS (Electronic Management System). When the gas rail temperature reaches a second temperature threshold, gas rail heating stops, and the "prohibit start" state bit is cleared to restore the EMS's start response. The control method provided in this application defines the "prohibit start" state bit and the heating status flag bit, using them as the basis for communication and decision-making between the EMS and the VCU (Vehicle Control Unit). This ensures a strict logical sequence between the heating process and the vehicle start command, preventing damage caused by forced start-up before ice blockage is resolved. Therefore, even for range extenders using a single gas fuel, the ice blockage problem can be gradually resolved.

[0063] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

[0064] It will be apparent to those skilled in the art that this application is not limited to the details of the exemplary embodiments described above, and that this application can be implemented in other specific forms without departing from the spirit or essential characteristics of this application. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this application is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this application. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A method for controlling gas rail heating, characterized in that, The method includes: During the first power-on or driving cycle, the gas rail temperature is acquired. When the gas rail temperature is lower than the first temperature threshold, the start-prohibited state bit is set, and gas rail heating is started, and the heating status flag bit is set. The start-prohibited state bit indicates that the VCU is prohibited from sending a start request to the EMS. When the gas rail temperature is heated to the second temperature threshold, heating of the gas rail is stopped, and the start-prohibited state bit is cleared to restore the EMS start-up response.

2. The gas rail heating control method as described in claim 1, characterized in that, After clearing the startup disable status bit, the method further includes: The decision to restart the gas rail heating depends on the status of the range extender and the temperature of the gas rail.

3. The gas rail heating control method as described in claim 2, characterized in that, The steps for determining whether to restart the gas rail heating based on the range extender's status and the gas rail temperature include: When the range extender is in operation, the gas rail heating is not activated; When the range extender is in a stopped state and the gas rail temperature is lower than the first temperature threshold, the start-prohibited state position is set again, and the gas rail heating is started until the gas rail temperature is heated to the second temperature threshold.

4. The gas rail heating control method as described in claim 1, characterized in that, The steps to start heating the gas rail include: Control the relay to close, thereby initiating the heating of the gas rail; The steps to stop heating the gas rail include: The control relay is disconnected to stop heating the gas rail.

5. The gas rail heating control method as described in claim 1, characterized in that, The VCU is prohibited from sending startup requests to the EMS, including: The EMS sends a boot-prohibited status bit to the VCU, so that the VCU is prohibited from sending boot requests.

6. The gas rail heating control method as described in claim 1, characterized in that, The first temperature threshold ranges from -30℃ to -10℃; the second temperature threshold ranges from -5℃ to 0℃.

7. The gas rail heating control method as described in claim 1, characterized in that, The criteria for determining the first power-on are: The entire vehicle's KL15 is powered on and the high voltage is on, and the engine status flag is in the off state.

8. A gas rail heating control system, characterized in that, For performing the gas rail heating control method as described in any one of claims 1 to 7, the system comprises: Temperature monitoring module, used to monitor the gas rail temperature in real time; A heating execution module is used to heat the gas rail during startup; EMS is connected to the temperature monitoring module and the heating execution module, and is used to generate and manage the prohibited start status bit and the heating status flag bit.

9. A range-extended vehicle, characterized in that, The range-extended vehicle includes an EMS, a VCU, a GCU, and a gas rail, wherein the EMS is configured to perform the method as described in any one of claims 1 to 8 to achieve active heating control of the gas rail.

10. The gas rail heating control method as described in claim 9, characterized in that, The range-extended vehicle is a single-fuel vehicle, and the single fuel includes natural gas and methanol.

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