A method for controlling the start-up of an E-power architecture generator-assisted engine

Abstract

The present invention provides an E-power architecture generator-assisted engine start control method, comprising the following steps: S1. judging whether the engine needs to be started according to the wheel-end power demand of the vehicle and the battery SOC value; S2. determining the control mode of the engine and the generator and the target output speed and target output torque of the generator when the engine needs to be started and the generator fault state level meets the requirements; S3. the HCU controller sends the target output speed, target output torque and preset fluctuation rate limit range of the generator to the generator control module to control the operation of the generator, thereby starting the engine; S4. the HCU controller judges whether the engine is started successfully according to whether the engine is in an idle condition, and continues to start the engine when the engine is not started successfully. This application saves the cost of installing the starter on the vehicle and saves the layout space of the whole vehicle by using the generator as a starter.

Description

Technical Field

[0001] The present invention belongs to the technical field of vehicle engine starting, and in particular relates to an E-power architecture generator-assisted engine starting control method. Background Art

[0002] HCU is the abbreviation of Hybrid Control Unit. HCU controller is the hybrid vehicle controller.

[0003] SOC, which stands for State Of Charge, is an important parameter in the use of power batteries, and is usually expressed as a percentage of the remaining battery power.

[0004] The current energy crisis and environmental pollution issues continue to attract attention and gradually become key factors affecting economic and social development. As people pay more attention to energy conservation and environmental protection and demand low carbon, hybrid vehicles continue to attract the attention of vehicle manufacturers, who have increased their research and development and production efforts for hybrid vehicles. E-power is a common hybrid vehicle architecture, and is used by many OEMs as a research object for the transition from traditional vehicles to new energy vehicles.

[0005] The hybrid vehicle with E-power architecture is composed of an engine, an engine controller, a generator, a generator controller, a battery, an electric motor, etc. The driving force of the whole vehicle is provided by the battery and the engine. The battery drives the electric motor to provide power for the whole vehicle, and the engine provides power to the generator to generate electricity, thereby driving the electric motor to provide power for the whole vehicle. The engine and the generator are rigidly connected. The engine does not directly drive the vehicle to move, but drives the generator to generate electricity to supply the electric motor connected to the wheels to drive the vehicle, thereby controlling the working point of the engine in an area with high combustion efficiency, thereby achieving energy conservation and emission reduction of the vehicle. The starter is required to start the engine. The starter is not only expensive, but also occupies the layout space of the whole vehicle.

[0006] This is a shortcoming of the prior art. Therefore, in view of the above-mentioned defects in the prior art, it is very necessary to provide an E-power architecture generator assisted engine starting control method. Summary of the invention

[0007] In view of the defect of the prior art that a starter needs to be installed when starting the engine of the existing E-power architecture vehicle, and that the starter occupies the layout space of the entire vehicle, the present invention provides an E-power architecture generator-assisted engine starting control method to solve the above technical problems.

[0008] The present invention provides an E-power architecture generator-assisted engine start control method, comprising the following steps:

[0009] S1. Determine whether the engine needs to be started based on the wheel-end power demand and battery SOC value of the E-power architecture vehicle, and set the engine start flag to the position when the engine needs to be started;

[0010] S2. When the engine needs to start the flag position and the generator fault status level meets the requirements, the HCU controller determines the control mode of the engine and the generator, and determines the target output speed and target output torque of the generator;

[0011] S3. The HCU controller sends the target output speed, target output torque and preset fluctuation rate limit range of the generator to the generator control module to control the operation of the generator, thereby starting the engine;

[0012] S4. The HCU controller receives the engine speed sent by the engine control module, and determines whether the engine is started successfully according to whether the engine is in an idle condition, and sets the engine not started flag to the position when the engine is not started successfully.

[0013] Furthermore, the specific steps of step S1 are as follows:

[0014] S11. Determine whether the current battery SOC value of the E-power architecture vehicle meets the current vehicle wheel-end power demand;

[0015] If yes, go to step S12;

[0016] If not, proceed to step S13;

[0017] S12. It is determined that the current operating condition does not require the engine to be started, and the battery provides energy for the motor to drive the vehicle, and the vehicle ends;

[0018] S13. Determine that the current working condition requires starting the engine, and set the flag position for starting the engine. Hybrid vehicles have multiple working modes. When the battery SOC value is low or the vehicle wheel-end power demand is large, and the current battery output power is insufficient to meet the vehicle wheel-end power demand, the engine needs to be started for power generation. Therefore, first determine whether the engine needs to be started under the current working condition based on the current vehicle wheel-end power demand value and battery SOC value, and send a flag position indicating that the engine needs to be started when the engine needs to be started.

[0019] Furthermore, the specific steps of step S2 are as follows:

[0020] S21.HCU controller determines whether the engine start flag is set;

[0021] If yes, go to step S22;

[0022] If not, do not start the engine and end;

[0023] S22. The HCU controller determines whether the engine not started flag is set;

[0024] If yes, go to step S23;

[0025] If not, the engine has been started, and there is no need to restart the engine, and the process ends;

[0026] S23.HCU controller determines that the fault status level of the generator meets the requirements;

[0027] If yes, go to step S24;

[0028] If not, do not start the engine and end;

[0029] S24. The HCU controller determines the engine control mode and the generator control mode and sends them to the corresponding control modules;

[0030] S25. The HCU controller determines the target output speed and target output torque of the generator according to the engine and generator control mode and the coolant temperature value. After determining that the engine needs to be started, the HCU controller also determines whether the current generator has a fault based on the fault information sent by the generator control module. For example, it can be assumed that if the current generator has a level 3 or higher fault, the generator cannot be controlled to start the engine.

[0031] Furthermore, the specific steps of step S23 are as follows:

[0032] S231. The HCU controller receives the fault information sent by the generator control module and determines whether the generator is faulty;

[0033] If not, proceed to step S234;

[0034] If yes, go to step S232;

[0035] S232. The HCU controller determines whether the generator fault level is greater than or equal to the fault level threshold;

[0036] If yes, go to step S233;

[0037] If not, proceed to step S234;

[0038] S233. The HCU controller determines that the generator fault status level does not meet the requirements, the engine does not start, and the process ends;

[0039] S234. The HCU controller determines that the generator fault state level meets the requirements and enters step S24. When there is no generator fault and the generator fault level is not high enough, the engine can be started.

[0040] Furthermore, the generator fault level threshold is set to level three.

[0041] Furthermore, the specific steps of step S24 are as follows:

[0042] S241. The HCU controller determines that the engine adopts the torque control mode, and sends the engine torque control mode to the engine control module via a CAN message;

[0043] S242. The HCU controller determines that the motor adopts the speed control mode, and sends the motor speed control mode to the generator control module via a CAN message;

[0044] S243. The HCU controller determines the first output speed value and the first output torque value of the generator when starting the engine. When the generator is fault-free and the engine speed is 0, the HCU controller controls the control mode of the generator and the engine, and sends it to the generator control module and the engine control module respectively in the form of CAN messages. When the generator starts the engine, the speed control mode is used for the generator, and the torque control mode is used for the engine.

[0045] Furthermore, the specific steps of step S25 are as follows:

[0046] S251. The HCU controller obtains the corresponding relationship between the coolant temperature and the generator speed value and torque value, and finds out the second output speed value and the second output torque value of the generator corresponding to the current coolant temperature;

[0047] S252. The HCU controller uses the smaller of the first output speed value and the second output speed value of the generator as the target output speed;

[0048] S253. The HCU controller uses the smaller of the first output torque value and the second output torque value of the generator as the target output torque. In order to prevent the engine coolant temperature from being too low when starting, it is necessary to give the generator speed value and torque value at different coolant temperatures, and take the smaller of the speed value and torque value given after determining the control mode to obtain the output speed value and torque value of the generator when starting the engine.

[0049] Furthermore, step S25 further includes:

[0050] S254. The HCU controller verifies whether the target output torque of the generator is positive;

[0051] If yes, go to step S3;

[0052] If not, determine that the generator output torque is wrong and end.

[0053] Furthermore, the specific steps of step S3 are as follows:

[0054] S31. The HCU controller obtains the target output speed of the generator and the preset speed fluctuation rate limit range, and sends it to the generator control module via a CAN message;

[0055] S32. The HCU controller obtains the target output torque of the generator and the preset torque fluctuation rate limit range, and sends them to the generator control module via a CAN message;

[0056] S33. The HCU controller controls the generator to operate according to the target output speed within the preset speed fluctuation rate limit range, and according to the target output torque within the preset torque fluctuation rate limit range to start the engine. In order to prevent the requested engine speed and torque values ​​from fluctuating too much and affecting the engine components, the rate of change of the speed and torque values ​​output by the generator is limited to protect the engine. The HCU sends the requested generator speed and torque values ​​to the generator control module in the form of CAN messages to control the operation of the generator to start the engine.

[0057] Furthermore, the specific steps of step S4 are as follows:

[0058] S41. The HCU controller receives the real-time engine speed sent by the engine control module to determine whether the engine is idling;

[0059] If yes, go to step S43;

[0060] If not, proceed to step S42

[0061] S42. The HCU controller determines that the engine is started successfully, controls the switching of the engine and generator control modes, exits the start process, and ends;

[0062] S43. The HCU controller determines that the engine has not started successfully, sets the engine not started flag, and returns to step S1. The engine control module sends the engine speed value to the HCU controller in the form of a CAN message. When the engine is idling, the HCU controller determines that the engine has started successfully, switches the control mode of the generator and the engine, and exits the starting process. If the engine has not started successfully, continue to start the engine.

[0063] The beneficial effects of the present invention are:

[0064] The E-power architecture generator-assisted engine start control method provided by the present invention fully considers the characteristics of the E-power architecture vehicle, solves the engine start problem of the vehicle under this architecture, and provides an engine start control method. In addition, there is no need to install a starter when the engine is started. Instead, by using the generator as a starter, the cost of installing the starter on the vehicle is saved and the layout space of the whole vehicle is saved; the generator failure may exist when the engine is started, and the judgment of the generator fault level is added; the limitation of the output speed and output torque of the generator during the temperature increase is also considered to avoid excessive speed and torque values ​​when starting the engine when the coolant temperature is relatively low, reducing the wear of the engine and increasing the service life of the engine; the influence of the fluctuation of the output speed and torque value of the generator on the engine during the engine start process is clearly considered, and the change rate of the output torque and output speed of the generator during the start process is limited, thereby optimizing the engine start process and strengthening the protection of the engine during the start process.

[0065] In addition, the invention has a reliable design principle, a simple structure and a very broad application prospect.

[0066] It can be seen that compared with the prior art, the present invention has outstanding substantive features and significant progress, and the beneficial effects of its implementation are also obvious. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0068] Figure 1 It is a flow chart of Example 1 of the E-power architecture generator assisted engine starting control method of the present invention.

[0069] Figure 2 It is a flow chart of Example 2 of the E-power architecture generator assisted engine starting control method of the present invention.

[0070] Figure 3 It is a flow chart of Example 2 of the E-power architecture generator assisted engine starting control method of the present invention. DETAILED DESCRIPTION

[0071] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0072] Embodiment 1:

[0073] like Figure 1 As shown, the present invention provides an E-power architecture generator assisted engine start control method, comprising the following steps:

[0074] S1. Determine whether the engine needs to be started based on the wheel-end power demand and battery SOC value of the E-power architecture vehicle, and set the engine start flag to the position when the engine needs to be started;

[0075] S2. When the engine needs to start the flag position and the generator fault status level meets the requirements, the HCU controller determines the control mode of the engine and the generator, and determines the target output speed and target output torque of the generator;

[0076] S3. The HCU controller sends the target output speed, target output torque and preset fluctuation rate limit range of the generator to the generator control module to control the operation of the generator, thereby starting the engine;

[0077] S4. The HCU controller receives the engine speed sent by the engine control module, and determines whether the engine is started successfully according to whether the engine is in an idle condition, and sets the engine not started flag to the position when the engine is not started successfully.

[0078] Embodiment 2:

[0079] like Figure 2 and Figure 3 As shown, the present invention provides an E-power architecture generator assisted engine start control method, comprising the following steps:

[0080] S1. Determine whether the engine needs to be started according to the wheel-end power demand and battery SOC value of the E-power architecture vehicle, and when the engine needs to be started, set the engine start flag to the position; the specific steps of step S1 are as follows:

[0081] S11. Determine whether the current battery SOC value of the E-power architecture vehicle meets the current vehicle wheel-end power demand;

[0082] If yes, go to step S12;

[0083] If not, proceed to step S13;

[0084] S12. Determine that the current operating condition does not require the engine to be started, and the battery provides energy for the motor to drive the vehicle, and the end; the specific steps of step S2 are as follows:

[0085] S21.HCU controller determines whether the engine start flag is set;

[0086] If yes, go to step S22;

[0087] If not, do not start the engine and end;

[0088] S22. The HCU controller determines whether the engine not started flag is set;

[0089] If yes, go to step S23;

[0090] If not, the engine has been started, and there is no need to restart the engine, and the process ends;

[0091] S23.HCU controller determines that the fault status level of the generator meets the requirements;

[0092] If yes, go to step S24;

[0093] If not, do not start the engine and end;

[0094] S24. The HCU controller determines the engine control mode and the generator control mode and sends them to the corresponding control modules;

[0095] S25. The HCU controller determines the target output speed and target output torque of the generator according to the engine and generator control modes and the coolant temperature value;

[0096] S13. Determine that the current operating condition requires the engine to be started, and set the engine start flag to position;

[0097] S2. When the engine needs to start the flag position and the generator fault status level meets the requirements, the HCU controller determines the control mode of the engine and the generator, and determines the target output speed and target output torque of the generator; the specific steps of step S2 are as follows:

[0098] S21.HCU controller determines whether the engine start flag is set;

[0099] If yes, go to step S22;

[0100] If not, do not start the engine and end;

[0101] S22. The HCU controller determines whether the engine not started flag is set;

[0102] If yes, go to step S23;

[0103] If not, the engine has been started, and there is no need to restart the engine, and the process ends;

[0104] S23.HCU controller determines that the fault status level of the generator meets the requirements;

[0105] If yes, go to step S24;

[0106] If not, end;

[0107] S24. The HCU controller determines the engine control mode and the generator control mode and sends them to the corresponding control modules;

[0108] S25. The HCU controller determines the target output speed and target output torque of the generator according to the engine and generator control modes and the coolant temperature value;

[0109] S3. The HCU controller sends the target output speed, target output torque and preset fluctuation rate limit range of the generator to the generator control module to control the operation of the generator, thereby starting the engine; the specific steps of step S3 are as follows:

[0110] S31. The HCU controller obtains the target output speed of the generator and the preset speed fluctuation rate limit range, and sends it to the generator control module via a CAN message;

[0111] S32. The HCU controller obtains the target output torque of the generator and the preset torque fluctuation rate limit range, and sends them to the generator control module via a CAN message;

[0112] S33. The HCU controller controls the generator to operate according to the target output speed within the preset speed fluctuation rate limit range and according to the target output torque within the preset torque fluctuation rate limit range to start the engine;

[0113] S4. The HCU controller receives the engine speed sent by the engine control module, and determines whether the engine is started successfully according to whether the engine is in an idle state, and sets the engine not started flag to a position when the engine is not started successfully; the specific steps of step S4 are as follows:

[0114] S41. The HCU controller receives the real-time engine speed sent by the engine control module to determine whether the engine is idling;

[0115] If yes, go to step S43;

[0116] If not, proceed to step S42

[0117] S42. The HCU controller determines that the engine is started successfully, controls the switching of the engine and generator control modes, exits the start process, and ends;

[0118] S43. The HCU controller determines that the engine has not started successfully, sets the engine not started flag to the position, and returns to step S1.

[0119] In some embodiments, step S23 includes the following steps:

[0120] S231. The HCU controller receives the fault information sent by the generator control module and determines whether the generator is faulty;

[0121] If not, proceed to step S234;

[0122] If yes, go to step S232;

[0123] S232. The HCU controller determines whether the generator fault level is greater than or equal to the fault level threshold;

[0124] If yes, go to step S233;

[0125] If not, proceed to step S234;

[0126] S233. The HCU controller determines that the generator fault status level does not meet the requirements, the engine does not start, and the process ends;

[0127] S234. The HCU controller determines that the generator fault status level meets the requirements and proceeds to step S24;

[0128] The specific steps of step S24 are as follows:

[0129] S241. The HCU controller determines that the engine adopts the torque control mode, and sends the engine torque control mode to the engine control module via a CAN message;

[0130] S242. The HCU controller determines that the motor adopts the speed control mode, and sends the motor speed control mode to the generator control module via a CAN message;

[0131] S243. The HCU controller determines a first output speed value and a first output torque value of the generator when starting the engine;

[0132] The specific steps of step S25 are as follows:

[0133] S251. The HCU controller obtains the corresponding relationship between the coolant temperature and the generator speed value and torque value, and finds out the second output speed value and the second output torque value of the generator corresponding to the current coolant temperature;

[0134] S252. The HCU controller uses the smaller of the first output speed value and the second output speed value of the generator as the target output speed;

[0135] S253. The HCU controller uses the smaller of the first output torque value and the second output torque value of the generator as the target output torque;

[0136] S254. The HCU controller verifies whether the target output torque of the generator is positive;

[0137] If yes, go to step S3;

[0138] If not, determine that the generator output torque is wrong and end.

[0139] Although the present invention has been described in detail by referring to the accompanying drawings and in combination with the preferred embodiments, the present invention is not limited thereto. Without departing from the spirit and essence of the present invention, a person of ordinary skill in the art may make various equivalent modifications or substitutions to the embodiments of the present invention, and these modifications or substitutions shall be within the scope of the present invention. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, and all of these shall be within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. An E-power architecture generator assisted engine start control method, characterized in that: The steps include: S1. Determine whether the engine needs to be started based on the wheel-end power demand and battery SOC value of the E-power architecture vehicle, and set the engine start flag to the position when the engine needs to be started; S2. When the engine needs to start the flag position and the generator fault status level meets the requirements, the HCU controller determines the control mode of the engine and the generator, and determines the target output speed and target output torque of the generator; S3. The HCU controller sends the target output speed, target output torque and preset fluctuation rate limit range of the generator to the generator control module to control the operation of the generator, thereby starting the engine; S4. The HCU controller receives the engine speed sent by the engine control module, and determines whether the engine is started successfully according to whether the engine is in an idle condition, and sets the engine not started flag to the position when the engine is not started successfully.

2. The E-power architecture generator assisted engine start control method according to claim 1, characterized in that: The specific steps of step S1 are as follows: S11. Determine whether the current battery SOC value of the E-power architecture vehicle meets the current vehicle wheel-end power demand; If yes, go to step S12; If not, proceed to step S13; S12. It is determined that the current operating condition does not require the engine to be started, and the battery provides energy for the motor to drive the vehicle, and the vehicle ends; S13. Determine that the current operating condition requires starting the engine, and set the engine start-need flag to the position.

3. The E-power architecture generator assisted engine start control method according to claim 1, characterized in that: The specific steps of step S2 are as follows: S21.HCU controller determines whether the engine start flag is set; If yes, go to step S22; If not, do not start the engine and end; S22. The HCU controller determines whether the engine not started flag is set; If yes, go to step S23; If not, the engine has been started, and there is no need to restart the engine, and the process ends; S23.HCU controller determines that the fault status level of the generator meets the requirements; If yes, go to step S24; If not, do not start the engine and end; S24. The HCU controller determines the engine control mode and the generator control mode and sends them to the corresponding control modules; S25. The HCU controller determines the target output speed and target output torque of the generator according to the engine and generator control modes and the coolant temperature value.

4. The E-power architecture generator assisted engine start control method as claimed in claim 3, characterized in that: The specific steps of step S23 are as follows: S231. The HCU controller receives the fault information sent by the generator control module and determines whether the generator is faulty; If not, proceed to step S234; If yes, go to step S232; S232. The HCU controller determines whether the generator fault level is greater than or equal to the fault level threshold; If yes, go to step S233; If not, proceed to step S234; S233. The HCU controller determines that the generator fault status level does not meet the requirements, the engine does not start, and the process ends; S234. The HCU controller determines that the generator fault status level meets the requirements and enters step S24.

5. The E-power architecture generator assisted engine start control method as claimed in claim 4, characterized in that: The generator fault level threshold is level three.

6. The E-power architecture generator assisted engine start control method as claimed in claim 3, characterized in that: The specific steps of step S24 are as follows: S241. The HCU controller determines that the engine adopts the torque control mode, and sends the engine torque control mode to the engine control module via a CAN message; S242. The HCU controller determines that the motor adopts the speed control mode, and sends the motor speed control mode to the generator control module via a CAN message; S243. The HCU controller determines a first output speed value and a first output torque value of the generator when starting the engine.

7. The E-power architecture generator assisted engine start control method as claimed in claim 6, characterized in that: The specific steps of step S25 are as follows: S251. The HCU controller obtains the corresponding relationship between the coolant temperature and the generator speed value and torque value, and finds out the second output speed value and the second output torque value of the generator corresponding to the current coolant temperature; S252. The HCU controller uses the smaller of the first output speed value and the second output speed value of the generator as the target output speed; S253. The HCU controller uses the smaller of the first output torque value and the second output torque value of the generator as the target output torque.

8. The E-power architecture generator assisted engine start control method as claimed in claim 6, characterized in that: Step S25 also includes: S254. The HCU controller verifies whether the target output torque of the generator is positive; If yes, go to step S3; If not, determine that the generator output torque is wrong and end.

9. The E-power architecture generator assisted engine start control method as claimed in claim 1, characterized in that: The specific steps of step S3 are as follows: S31. The HCU controller obtains the target output speed of the generator and the preset speed fluctuation rate limit range, and sends it to the generator control module via a CAN message; S32. The HCU controller obtains the target output torque of the generator and the preset torque fluctuation rate limit range, and sends them to the generator control module via a CAN message; S33. The HCU controller controls the generator to operate according to the target output speed within the preset speed fluctuation rate limit range, and according to the target output torque within the preset torque fluctuation rate limit range, to start the engine.

10. The E-power architecture generator assisted engine start control method as claimed in claim 1, characterized in that: The specific steps of step S4 are as follows: S41. The HCU controller receives the real-time engine speed sent by the engine control module to determine whether the engine is idling; If yes, go to step S43; If not, proceed to step S42 S42. The HCU controller determines that the engine is started successfully, controls the switching of the engine and generator control modes, exits the start process, and ends; S43. The HCU controller determines that the engine has not started successfully, sets the engine not started flag to the position, and returns to step S1.

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