Hybrid power system for undergraduate formula car and racing car thereof

Abstract

According to the hybrid power system for the undergraduate formula racing car and the racing car thereof, traditional belt transmission is abandoned, and the mode that a motor is directly connected with an engine crankshaft through a connector is adopted, so that the transmission efficiency is improved, and belt slipping is avoided; according to the design, the change of the engine is reduced, the design difficulty and cost are reduced, and meanwhile, the dynamic property and economical efficiency of the whole vehicle are improved. Besides, the system can operate in a pure engine driving mode and a motor and engine combined driving mode, and torque output of the engine and the motor is intelligently distributed through an accurate control strategy according to the battery charge state and the actual torque requirement. The light hybrid system not only simplifies the energy transfer link, but also improves the integration level of the hybrid power system, so that the hybrid power system is very suitable for the use requirements of formula racing cars of college students, and shows remarkable advantages in performance and efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of formula student hybrid power racing cars, and in particular to a hybrid power system for formula student racing cars and a racing car thereof. Background Art

[0002] The Formula Student competition is a comprehensive car design and manufacturing competition, mainly for college students majoring in automotive engineering or related majors; these participating cars must comply with strict design specifications, including restrictions on engine displacement, hybrid system voltage and energy storage device weight. Although existing racing cars have made some progress in hybrid technology, there are still some shortcomings in the design and efficiency of the power system.

[0003] Currently, many fleets use a layout where the front wheels are driven by dual-wheel-hub motors and the rear wheels are driven by internal combustion engines. Although this layout can achieve high mechanical efficiency four-wheel drive, the use of wheel-hub motors increases the non-suspension mass, which in turn increases the difficulty of wheel-side design. Specifically, the current passenger car hybrid systems on the market are mainly driven by internal combustion engines and assisted by motors; among them, parallel P0 and P1 hybrid systems are the mainstream.

[0004] At present, the P0 hybrid system uses a BSG motor, which is connected to the engine through a belt, effectively using the characteristics of belt drive to transmit power. When the engine is running, a small amount of energy will be transferred to the motor for power generation; however, this design has problems with low transmission efficiency and belt slippage. The P1 hybrid system uses an ISG motor, which is directly connected to the engine. Although it can recover braking energy, the motor is large in size, requires large changes to the engine, has low space utilization, and is complex to arrange. It can be seen that although the P0 and P1 hybrid systems are very popular in the field of passenger cars, they are not applicable in Formula Student racing.

[0005] In view of this, this application is filed. Summary of the invention

[0006] The present invention provides a hybrid power system for a Formula Student racing car and a racing car thereof, which can at least partially improve the above-mentioned problems.

[0007] To achieve the above object, the present invention adopts the following technical solutions: A hybrid power system for a Formula Student racing car, comprising: an electric energy storage component, an internal combustion engine, a hybrid motor, a control component, and a connector component, wherein an output end of the electric energy storage component is electrically connected to a power supply end of the control component, an output end of the control component is electrically connected to an input end of the hybrid motor, an output end of the control component is communicatively connected to an input end of the internal combustion engine, the internal combustion engine is mechanically connected to the hybrid motor via the connector component, and the internal combustion engine is used to be mechanically connected to a main reducer of the Formula Student racing car; The vehicle controller of the control assembly is configured to implement the following steps by executing a computer program stored therein: Obtain battery charge state SOC, actual torque demand T required , and determine whether the battery state of charge SOC is greater than the preset allowable minimum battery state of charge SOC L ; If so, the hybrid motor is controlled to start, and the actual torque requirement T required outputting torque to the internal combustion engine and the hybrid motor respectively; When the actual torque demand T required When the torque is greater than the maximum torque output by the internal combustion engine, the combined driving mode is entered to control the internal combustion engine and the hybrid motor to jointly drive the Formula Student car; When it is determined that the output of the internal combustion engine is in a preset low efficiency region, the electric energy storage component is controlled to provide electric energy to the hybrid motor, so that the hybrid motor assists in driving the Formula Student car; When it is determined that the battery state of charge SOC is greater than the preset maximum allowable battery state of charge SOC H When the electric energy storage component is controlled to provide electric energy to the hybrid motor, the hybrid motor drives the Formula Student car.

[0008] The present invention also provides a Formula Student racing car, comprising: a vehicle body and a hybrid power system for a Formula Student racing car as described in any one of the above items, wherein the hybrid power system for a Formula Student racing car is configured on the vehicle body.

[0009] In summary, the hybrid power system for the Formula Student car is a 48V mild hybrid system, which is a layout scheme suitable for the Formula Student hybrid power system provided for the Formula Student hybrid power car. Compared with the traditional P0 configuration hybrid system, the hybrid power system for the Formula Student car also has the motor installed at the front end of the engine, but the belt drive is cancelled, and the motor is connected to the engine crankshaft, replacing the engine's magnetic cylinder. This not only effectively solves the factors such as low belt drive efficiency and easy slippage, but also effectively controls the size of the motor, with less modification to the engine, reducing the design difficulty and cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 is a schematic diagram of the architecture of a hybrid power system for a Formula Student car provided by an embodiment of the present invention; Figure 2 is a simplified structural arrangement diagram of a hybrid power system for a Formula Student car provided by an embodiment of the present invention; Figure 3 is a schematic diagram of an engine driving mode of a hybrid power system for a Formula Student racing car provided by an embodiment of the present invention; Figure 4 is a schematic diagram of a hybrid driving mode of a hybrid power system for a Formula Student racing car provided by an embodiment of the present invention; Figure 5 is a schematic diagram of a hybrid control form provided by an embodiment of the present invention; Figure 6 is a schematic diagram of working modes under different SOCs provided by an embodiment of the present invention; Figure 7 is a schematic diagram of the overall structure of a hybrid power system for a Formula Student car provided by an embodiment of the present invention; Figure 8 It is a structural explosion diagram of a hybrid power system for a Formula Student racing car provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0011] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0012] refer to Figure 1 , Figure 2As shown, the first embodiment of the present invention discloses a hybrid power system for a Formula Student racing car, which includes: an energy storage component, an internal combustion engine, a hybrid motor, a control component, and a connector component, the output end of the energy storage component is electrically connected to the power supply end of the control component, the output end of the control component is electrically connected to the input end of the hybrid motor, the output end of the control component is communicatively connected to the input end of the internal combustion engine, the internal combustion engine is mechanically connected to the hybrid motor through the connector component, and the internal combustion engine is used to mechanically connect to the main reducer of the Formula Student racing car.

[0013] In this embodiment, the hybrid power system for the Formula Student racing car includes an energy storage component, an internal combustion engine ICE, a hybrid motor, a control component, and a connector component, wherein the motor is used to generate electricity, assist engine driving, and adjust the engine operating point; the engine is used to drive the wheels and drive the motor to generate electricity.

[0014] Preferably, the electric energy storage component includes a power battery and a battery management system, the output end of the power battery is electrically connected to the input end of the battery management system, and the output end of the battery management system is electrically connected to the power supply end of the control component.

[0015] In this embodiment, the power battery is used to store and release electrical energy, and the battery management system is integrated to achieve reasonable management of the power battery, ensure the accuracy of the collected data, the reliability and stability of the system communication, and the anti-interference. Among them, when the power battery provides energy to the motor, the battery charge state needs to be considered. The battery state is related to whether the motor is used for driving or for power generation, and it is necessary to ensure that the engine runs in the high-efficiency area as much as possible, while ensuring that the battery is at the upper limit SOC. H and lower limit SOC L It should be noted that SOC L Indicates the lowest allowed battery state of charge, but the power battery still has a small amount of power.

[0016] Preferably, the control component includes a vehicle controller, a motor controller, and an engine controller. The output end of the energy storage component is electrically connected to the power supply end of the motor controller, the motor controller is electrically connected to the hybrid motor, the vehicle controller is communicatively connected to the motor controller, the engine controller is communicatively connected to the internal combustion engine, and the vehicle controller is CAN communicatively connected to the energy storage component and the engine controller.

[0017] In this embodiment, the motor controller is used to receive signals from the vehicle controller to control the motor. At the same time, the controller integrates a rectifier, which can convert the AC power generated by the motor into DC power and provide it to the power battery and other power-consuming devices. It has multiple protection mechanisms, such as battery input protection and overload protection, to ensure the safety and stable operation of the system. The vehicle controller controls the entire hybrid system, coordinates the motor controller with the engine controller, and ensures the stable operation of the hybrid system.

[0018] See also Figure 5 Preferably, the vehicle controller can collect the racing information of the current Formula Student racing car, wherein the racing information includes the battery charge state SOC, the actual torque demand T required , pedal position, brake pressure, vehicle speed.

[0019] In this embodiment, the vehicle controller collects parameters such as pedal position, brake pressure, vehicle speed, battery status, etc., and controls the torque output of the hybrid motor through a predetermined strategy.

[0020] See also Figure 7 , Figure 8 Preferably, the connector assembly includes a crankshaft connector and a motor connector, one end of the crankshaft connector is connected to the crankshaft of the internal combustion engine, the other end of the crankshaft connector is connected to the motor connector through a flange, and the motor connector is connected to the hybrid motor through screws.

[0021] In this embodiment, the keyway at the crankshaft connector cooperates with the key at the end of the engine crankshaft, and is connected to the flange at the motor connector through a flange to achieve power transmission. Specifically, the connection between the motor and the engine is a mechanical connection. The motor is connected to the engine crankshaft through a connector. During this process, the engine needs to be modified to a certain extent. The engine hood through hole is connected. To ensure assembly, the crankshaft connector is first connected to the crankshaft, and then connected to the motor connector through a flange. The motor has both starting and power generation functions. When it needs to be started, the motor drives the crankshaft to start. When charging is required, the crankshaft rotates to drive the motor to generate electricity. The main body of the engine is retained, the space of the whole vehicle is effectively utilized, the difficulty of layout is reduced, the structure of the whole vehicle is simple and compact, and the cost is effectively reduced, which meets the layout requirements of the Formula Series racing car.

[0022] Specifically, in this embodiment, the motor is installed on the engine crankshaft, so the engine speed is the same as the motor, the power of the engine and the motor is coupled on the crankshaft, and then the vehicle is driven by the transmission system composed of a clutch, a transmission, a main reducer and a half shaft. The motor and the engine are torque coupled. When the car is in an acceleration condition, when the driver steps on the accelerator pedal, the vehicle controller collects the pedal position signal and the power battery status, and distributes the torque according to the established strategy. The vehicle controller exchanges information with the engine controller, the motor controller and the battery management system through the CAN network. The vehicle controller controls the hybrid power system and the engine controller controls the engine independently. The motor controller controls the motor to work, and the engine and the motor jointly output power. When the car is decelerating, the vehicle controller collects the brake pressure signal. According to the established strategy, the motor does not intervene in the work, and the engine works alone.

[0023] See also Figure 6 The vehicle controller of the control component is configured to implement the following steps by executing a computer program stored therein: Obtain battery charge state SOC, actual torque demand T required , and determine whether the battery state of charge SOC is greater than the preset allowable minimum battery state of charge SOC L ; If so, the hybrid motor is controlled to start, and the actual torque requirement T required outputting torque to the internal combustion engine and the hybrid motor respectively; When the actual torque demand T required When the torque is greater than the maximum torque output by the internal combustion engine, the combined driving mode is entered to control the internal combustion engine and the hybrid motor to jointly drive the Formula Student car; When it is determined that the output of the internal combustion engine is in a preset low efficiency region, the electric energy storage component is controlled to provide electric energy to the hybrid motor, so that the hybrid motor assists in driving the Formula Student car; When it is determined that the battery state of charge SOC is greater than the preset maximum allowable battery state of charge SOC H When the electric energy storage component is controlled to provide electric energy to the hybrid motor, the hybrid motor drives the Formula Student car.

[0024] Preferably, the actual torque requirement T required = Distributed engine torque T E + Distributed motor torque T M .

[0025] In this embodiment, the system includes two working modes: pure engine drive and engine and motor combined drive. According to the actual torque demand, the motor and the engine are jointly provided. required =T E +T M , the required torque is the sum of the engine torque and the motor torque. At the same time, the timing of motor intervention gives priority to the power battery charge state, followed by the engine working state, as follows: When the motor and the engine are driven together, the power battery provides electrical energy to the motor, and the motor and the engine work together to adjust the engine operating point to the area with the best fuel efficiency, that is, the hybrid drive mode. This structure is not only compact, but also enables the racing car to have good fuel economy and power performance, and has high stability. The battery capacity is small, and the hybrid motor only serves as an auxiliary power. Figure 4 shown.

[0026] Specifically, when battery SOC>SOC L At this time, the motor is responsible for starting. At the same time, the motor and engine output torque are distributed according to the actual torque demand. If the required torque is greater than the maximum torque output of the engine, the motor and engine are driven together. At the same time, if the engine is in a low efficiency area at this time, the motor intervenes to assist the drive and put the engine in a high efficiency area. At the same time, if the SOC value is greater than SOC H , the motor intervenes in the drive, consuming the power battery to store electrical energy.

[0027] Preferably, it also includes: When it is determined that the battery state of charge SOC is less than the preset minimum allowable battery state of charge SOC L When the hybrid motor is controlled to start; Controlling the internal combustion engine to drive the Formula Student racing car: Wherein, the internal combustion engine drives the hybrid motor to rotate through the connector assembly, and supplies power to the energy storage assembly in reverse.

[0028] like Figure 3 As shown, in this embodiment, when the engine is working, the motor is in a closed state, and the rotation of the crankshaft drives the motor to generate electricity, converting kinetic energy into electrical energy to supply the power battery, that is, the driving charging mode. In this process, the engine not only drives the racing car to run, but also needs to provide energy to the power battery.

[0029] Specifically, when the battery SOC <SOC L When the motor is in operation, the motor is responsible for starting. After the start is completed, click "Do not participate in the work". At this time, the output power is provided by the engine, and the engine drives the motor to supply power to the power battery through the rotation of the crankshaft. When the start is completed and it is in the idle state, the motor does not intervene in the work.

[0030] Specifically, in this embodiment, the hybrid power system for the Formula Student car integrates the hybrid motor for starting and generating electricity. The starter motor on the original engine is discarded, and the hybrid motor is used to start the engine. The hybrid motor's regulation of the engine speed can bring better economy and power. The motor regulates the engine speed so that the engine is in the high-efficiency speed range and enters the high-efficiency zone, thereby improving economy. In the driving charging mode, in addition to providing the driving force required for the vehicle to travel, the engine also charges the power battery. At this time, the drive motor is turned off.

[0031] In summary, the hybrid power system for the student formula car provides a 48v mild hybrid system that is mainly driven by the engine and supplemented by a single motor drive; it is modified based on the parallel P0 configuration, and does not need to use the traditional belt to transmit the motor power, which reduces the transmission power loss and avoids belt slippage. Although the motor of the hybrid power system for the student formula car is connected to the crankshaft, it is different from the parallel P1 configuration; this system abandons the original magnetic cylinder and starter motor of the engine, effectively controls the size of the motor, and also reduces the changes to the engine, reduces the design difficulty and cost, and improves the power and economy of the whole vehicle. At the same time, this solution improves the integration of the hybrid power system, reduces the complexity of the transmission system, and simplifies the energy transfer link. In short, the hybrid power system for the student formula car uses a smaller power motor to meet the use requirements of the hybrid power. It can be effectively applied to the student formula hybrid car.

[0032] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A hybrid power system for a Formula Student car, characterized in that: include: An electric energy storage component, an internal combustion engine, a hybrid motor, a control component, and a connector component, wherein the output end of the electric energy storage component is electrically connected to the power supply end of the control component, the output end of the control component is electrically connected to the input end of the hybrid motor, the output end of the control component is communicatively connected to the input end of the internal combustion engine, the internal combustion engine is mechanically connected to the hybrid motor via the connector component, and the internal combustion engine is used to be mechanically connected to the main reducer of the Formula Student racing car; The vehicle controller of the control assembly is configured to implement the following steps by executing a computer program stored therein: Obtain battery charge state SOC, actual torque demand T required , and determine whether the battery state of charge SOC is greater than the preset allowable minimum battery state of charge SOC L ; If so, the hybrid motor is controlled to start, and the actual torque requirement T required outputting torque to the internal combustion engine and the hybrid motor respectively; When the actual torque demand T required When the torque is greater than the maximum torque output by the internal combustion engine, the combined driving mode is entered to control the internal combustion engine and the hybrid motor to jointly drive the Formula Student car; When it is determined that the output of the internal combustion engine is in a preset low efficiency region, the electric energy storage component is controlled to provide electric energy to the hybrid motor, so that the hybrid motor assists in driving the Formula Student car; When it is determined that the battery state of charge SOC is greater than the preset maximum allowable battery state of charge SOC H When the electric energy storage component is controlled to provide electric energy to the hybrid motor, the hybrid motor drives the Formula Student car.

2. The hybrid power system for a Formula Student car according to claim 1, characterized in that: Also includes: When it is determined that the battery state of charge SOC is less than the preset minimum allowable battery state of charge SOC L When the hybrid motor is controlled to start; Controlling the internal combustion engine to drive the Formula Student racing car; Wherein, the internal combustion engine drives the hybrid motor to rotate through the connector assembly, and supplies power to the energy storage assembly in reverse.

3. The hybrid power system for a Formula Student car according to claim 1, characterized in that: Actual torque requirement T required = Distributed engine torque T E + Distributed motor torque T M .

4. The hybrid power system for a Formula Student car according to claim 1, characterized in that: The electric energy storage component includes a power battery and a battery management system. The output end of the power battery is electrically connected to the input end of the battery management system, and the output end of the battery management system is electrically connected to the power supply end of the control component.

5. The hybrid power system for a Formula Student car according to claim 1, characterized in that: The control component includes a vehicle controller, a motor controller, and an engine controller. The output end of the energy storage component is electrically connected to the power supply end of the motor controller, the motor controller is electrically connected to the hybrid motor, the vehicle controller is communicatively connected to the motor controller, the engine controller is communicatively connected to the internal combustion engine, and the vehicle controller is CAN-communicatively connected to the energy storage component and the engine controller.

6. The hybrid power system for a Formula Student car according to claim 5, characterized in that: The vehicle controller can collect racing information of the current Formula Student racing car, wherein the racing information includes battery state of charge SOC, actual torque demand Trequired, pedal position, brake pressure, and vehicle speed.

7. The hybrid power system for a Formula Student car according to claim 1, characterized in that: The connector assembly comprises a crankshaft connector and a motor connector, wherein one end of the crankshaft connector is connected to the crankshaft of the internal combustion engine, the other end of the crankshaft connector is connected to the motor connector via a flange, and the motor connector is connected to the hybrid motor via screws.

8. A student formula car, characterized in that: It comprises a vehicle body and a hybrid power system for a Formula Student racing car as claimed in any one of claims 1 to 7, wherein the hybrid power system for a Formula Student racing car is arranged on the vehicle body.

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