Intelligent braking method, device and equipment supporting vehicle-mounted Ethernet

Abstract

The invention relates to an intelligent braking method supporting a vehicle-mounted Ethernet, and the method comprises the steps: carrying out the development according to an MCAL, configuring an Ethernet hardware initialization environment, transplanting an LWIP protocol on an Ethernet data link layer, adding TCP and UDP application layer protocols, achieving an Ethernet communication function, building a hardware facility according to an MCU chip, installing a PHY chip on a peripheral circuit, and connecting the PHY chip with the MCU, according to the method, Ethernet physical layer processing capability is obtained, motor algorithm control is carried out according to a self-developed SPWM algorithm, the PWM duty ratio of a control end is changed by the SPWM algorithm through the table amplitude of a sine table, and a speed closed loop is added to control the rotating speed of a motor. According to the system, the pedal displacement can be collected through the sensor to drive the motor to conduct braking, the braking force is improved, high-speed Ethernet communication is introduced, multi-path CAN communication is reserved, stability and real-time performance of data transmission are achieved, and powerful support is provided for research and development of related fields.

Description

Technical Field

[0001] The present application relates to the field of vehicle-mounted communication technology, and in particular to an intelligent braking method, device and equipment supporting vehicle-mounted Ethernet. Background Art

[0002] In modern automotive control, the braking system is a crucial component for ensuring safe and stable vehicle operation. With the advancement of modern technology, brake control systems have evolved from traditional mechanical braking to electronic control. Electronic control units precisely control brake pressure, improving braking response speed and stability. Furthermore, traditional automotive braking systems are gradually evolving towards intelligent and networked systems. Automotive Ethernet, as a high-speed, reliable in-vehicle communication protocol, is becoming a core component of next-generation automotive electronic architectures due to its high bandwidth, low latency, and excellent interoperability.

[0003] Traditional braking systems often suffer from the following issues: Insufficient braking force. In early automobiles, braking systems primarily relied on mechanical connections and hydraulics, which often resulted in insufficient braking force. Rapid wear. Common braking systems primarily rely on the friction changes caused by the driver's pedal pressure to control the braking system. Braking control often requires combining driver force with pedal force. This overreliance on friction can lead to accelerated wear of the brake pedal. Slow response. Traditional braking systems often rely solely on CAN communication for data transmission. Standard CAN communication typically has a transmission rate of 10Kbps to 1Mbps, which is a disadvantage for slow response in modern automotive control systems. Complex braking systems, in particular, require stable and high-speed data transmission. Furthermore, detecting node faults in CAN communication is difficult, requiring specialized software and equipment for diagnosis, which significantly inconveniences subsequent maintenance. Summary of the Invention

[0004] The present application provides an intelligent braking method supporting vehicle-mounted Ethernet, characterized by comprising:

[0005] Develop according to MCAL, configure the Ethernet hardware initialization environment, transplant the LWIP protocol on the Ethernet data link layer, add TCP and UDP application layer protocols, and realize Ethernet communication functions;

[0006] Build hardware facilities based on the MCU chip, install the PHY chip in the peripheral circuit and connect it to the MCU to obtain Ethernet physical layer processing capabilities;

[0007] The SPWM algorithm is used for motor algorithm control. The PWM duty cycle of the control end is changed by the amplitude of the sine table. The motor speed is controlled by the duty cycle. A speed closed loop is added and the scheduling coefficient is used for control.

[0008] Optionally, the development is performed based on MCAL, configuring the Ethernet hardware initialization environment, porting the LWIP protocol to the Ethernet data link layer, adding TCP and UDP application layer protocols, and implementing Ethernet communication functions, including:

[0009] The configuration of the Ethernet hardware initialization environment is to achieve 100M communication rate, MII communication mode, standard MAC layer subtype, MAC address and ring queue buffer settings based on MCAL;

[0010] The LWIP protocol is transplanted on the Ethernet data link layer to initialize the Ethernet with software after the hardware environment is ready, and the LWIP protocol is transplanted to encapsulate the data frames transmitted by the Ethernet, and associate the local IP address, mask and gateway;

[0011] The addition of TCP and UDP application layer protocols is to realize the data transmission function of Ethernet based on TCP and UDP.

[0012] Optionally, building hardware facilities based on the MCU chip, installing a PHY chip in the peripheral circuit and connecting it to the MCU to obtain Ethernet physical layer processing capabilities, includes:

[0013] The PHY chip obtains a reference clock through an external crystal oscillator and obtains power through an external circuit;

[0014] The connection with the MCU is that the MCU is connected to the corresponding pins of the PHY chip by configuring the corresponding pin mode.

[0015] Optionally, the motor algorithm control is performed using an SPWM algorithm, the PWM duty cycle of the control end is changed by the table amplitude of the sine table, the motor speed is controlled by the duty cycle, and a speed closed loop is added, and the control is performed using a scheduling coefficient, including:

[0016] The PWM duty cycle of the control end is changed by the table amplitude of the sine table, a sampling point is set for the modulated sine wave to select the SPWM asymmetric rule, and the sine table is listed for the PWM wave duty cycle using the expected voltage at the sampling point, so as to update the PWM wave duty cycle using the sine table in each call cycle;

[0017] The added speed closed loop uses a scheduling coefficient for control, and a proportional coefficient is set for the error between the actual speed and the expected speed to adjust the speed. The speed is adjusted by changing the whole wave period.

[0018] Optionally, the connecting with the MCU is connecting the MCU with corresponding pins of the PHY chip by configuring a corresponding pin mode, including:

[0019] The corresponding pins of the PHY chip are the MDC pin for synchronous data transmission, the MDIO pin for configuring the chip, four pairs of Tx and Rx pins for sending and receiving, the TXC and RXC pins for providing data transmission clock, and the RXER pin for outputting error status.

[0020] Optionally, the intelligent braking method supporting vehicle Ethernet is characterized by:

[0021] The asymmetric regular sampling formula is:

[0022] Ton1=(1+M*sin(pi*k / N))*Tc / 4[k=0,2,4,6...2N-2]

[0023] Ton2=(1+M*sin(pi*k / N))*Tc / 4[k=1,3,5,7...2N-1]

[0024] Ton=Ton1+Ton2

[0025] Ton1 and Ton2 are the comparison positions of each sampling point of the modulated sine wave and the carrier, Ton is the PWM period to be set, Tc is a complete period of the carrier, M is the set modulation coefficient, and N is the number of set sampling points;

[0026] The sinusoidal relationship between the motor speed and modulation in the speed closed loop is:

[0027] Speed = Ts / k [k = 4.494]

[0028] Optionally, the intelligent braking method supporting vehicle Ethernet is characterized by:

[0029] While introducing Ethernet communication, multi-channel CAN communication is retained;

[0030] The Ethernet function uses MII mode and can use four data lines for data transmission.

[0031] The present application also provides a device for intelligent braking supporting in-vehicle Ethernet, characterized in that the device includes: a CAN transceiver, a brushless DC motor, a sensor, an MCU chip and a PHY chip.

[0032] Optionally, the device for intelligent braking supporting in-vehicle Ethernet is characterized in that: the CAN transceiver is used to send and receive data on the CAN bus, the brushless DC motor is used to convert electrical energy into mechanical energy, the sensor is used to detect physical quantities of the environment or objects and convert them into electrical signals, the MCU chip is used to support Ethernet communication, and the PHY chip is used to implement Ethernet communication at the physical layer.

[0033] The present application also provides an electronic device, characterized by comprising:

[0034] An MCU chip and a PHY chip, wherein the MCU chip is used to support Ethernet communication, and the PHY chip is used to process the Ethernet physical layer, wherein the Ethernet communication and processing implement any of the steps of the intelligent braking method supporting vehicle-mounted Ethernet.

[0035] The beneficial effects of this application are: using sensors to collect pedal displacement to drive the motor for braking not only improves the braking force, but also introduces high-speed Ethernet communication and retains multi-channel CAN communication, achieving stability and real-time data transmission. This invention provides strong support for research and development in related fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required in the embodiments or the description of the prior art. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0037] Figure 1 A flow chart showing an intelligent braking method supporting vehicle Ethernet disclosed in this application is shown;

[0038] Figure 2 A specific functional block diagram of an intelligent braking method supporting vehicle Ethernet disclosed in this application is shown;

[0039] Figure 3 A system mind map showing an intelligent braking method supporting vehicle Ethernet disclosed in this application;

[0040] Figure 4 A circuit diagram of a braking system supporting an intelligent braking method for vehicle-mounted Ethernet disclosed in this application is shown. DETAILED DESCRIPTION

[0041] Various exemplary embodiments, features, and aspects of the present application will be described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise indicated.

[0042] The terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0043] The word “exemplary” is used exclusively herein to mean “serving as an example, example, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

[0044] In addition, numerous specific details are provided in the following detailed description to better illustrate the present application. Those skilled in the art will appreciate that the present application can be practiced without certain specific details. In some instances, methods, means, components, and circuits well known to those skilled in the art are not described in detail in order to highlight the main purpose of the present application.

[0045] This application is an intelligent braking method that supports in-vehicle Ethernet. In this method, in addition to retaining the original CAN communication, 100M Ethernet communication is introduced to ensure the stability and efficiency of the braking system data transmission. Based on the fault detection mechanism of the in-vehicle Ethernet itself, it also provides great convenience for fault detection and maintenance. The system can collect external switch quantities to achieve electronic parking. After collecting data through sensors, it can drive the motor to establish hydraulic pressure to generate braking force and reduce pedal wear. At the same time, with efficient motor control algorithms and the collection of multiple sensors, it achieves precise control of the motor speed. By setting the speed, the speed can be accurately changed at any time, so that the motor can achieve a speed of more than 20 revolutions per second. In addition, the braking force of this braking system is completely provided by the motor, avoiding the disadvantage of insufficient braking force.

[0046] like Figure 1 FIG. 1 is a flow chart of an intelligent braking method supporting vehicle Ethernet according to an embodiment of the present application, which specifically includes the following contents:

[0047] S100 is developed based on MCAL, configures the Ethernet hardware initialization environment, transplants the LWIP protocol on the Ethernet data link layer, adds TCP and UDP application layer protocols, and realizes Ethernet communication functions.

[0048] Specifically, first configure MCAL with clocks, pin multiplexing, and interrupt settings to ensure the hardware supports Ethernet communication. Secondly, after MCAL configuration is complete, initialize the Ethernet controller by setting the communication rate, communication mode, MAC address, and buffer. Then, after hardware initialization is complete, Ethernet frame sending and receiving functions can be implemented directly at the data link layer. The LWIP protocol is then ported to the data link layer to obtain complete network protocol support and associate network configurations, including IP addresses. Finally, based on the LWIP protocol stack, TCP and UDP protocols are added. TCP is used for scenarios requiring reliable transmission, such as remote control, and UDP is used for scenarios with high real-time requirements, such as sensor data acquisition.

[0049] S200 builds hardware facilities based on the MCU chip, installs the PHY chip in the peripheral circuit and connects it to the MCU to obtain the Ethernet physical layer processing capabilities.

[0050] Specifically, since there is no PHY chip integrated inside the MCU chip, the PHY chip is placed in the peripheral circuit and connected to the MCU through a standard Ethernet interface in MII mode. The main function of the PHY chip is to perform Ethernet physical layer processing such as signal decoding and encoding.

[0051] S300 uses the SPWM algorithm for motor algorithm control, changes the PWM duty cycle of the control end through the amplitude of the sine table, controls the motor speed through the duty cycle, adds a speed closed loop, and uses the scheduling coefficient for control.

[0052] Specifically, the expected voltage value at each sampling point is calculated based on the frequency and amplitude of the sine wave. This is then mapped to the PWM duty cycle to generate a sine table. The current duty cycle value in the sine table is read during each SPWM call cycle, and the PWM duty cycle is updated via the MCAL interface. Finally, an SPWM waveform is generated based on the updated duty cycle and converted to a smooth sine wave using a low-pass filter to drive the motor. A speed closed-loop control is also added to achieve smoother motor speed control by setting the modulation coefficient.

[0053] In summary, this method has lower latency and higher data bandwidth in data transmission based on Ethernet communication, and can seamlessly connect this braking system with other advanced functions of the car (such as the body control system). In addition, Ethernet supports flexible network topology, which allows the present invention to freely adjust and expand the network layout as needed. The self-developed SPWM algorithm is used for control on the motor control algorithm to directly call the MCAL library function to update the duty cycle without the need for additional calculations, thereby improving the execution efficiency of the algorithm. At the same time, the use of a sine table to update the duty cycle also improves the robustness of the program. The software characteristics of MCAL make the algorithm easier to transplant. The speed closed loop added to the self-developed SPWM algorithm dynamically adjusts the motor speed to the expected speed, so that the motor has good dynamic performance when driven, as well as strong anti-interference ability, and can reduce speed fluctuations and improve control accuracy.

[0054] like Figure 2 As shown in the figure, the specific functional block diagram of the intelligent braking method supporting automotive Ethernet includes the following:

[0055] Using NXP's S32K344 chip as the main controller, the system accurately collects data from pressure sensors, angle sensors, and pedal sensors, providing feedback to the controller to drive the three-phase brushless DC motor. A solenoid valve controls the flow of brake fluid, generating hydraulic pressure for braking. The system retains three CAN transceivers and adds a 100M Ethernet communication port to ensure high-performance data transmission. It also supports signal input for electronic parking, wheel speed detection, and fluid level detection.

[0056] The system communicates with upper-layer applications in the braking system (such as the transmission control unit, chassis control unit, and vehicle diagnostic system) via Ethernet. Data is obtained and transmitted to the braking system's MCU. After processing the data, the MCU drives relevant sensors, such as controlling the output PWM wave to activate and deactivate the bottom-side drive solenoid valve, which then discharges brake fluid. This in turn invokes the motor drive algorithm to change the motor's motion state, pushing brake fluid into the vacuum line to generate braking force. Alternatively, the MCU processes the data to control the output of the SENT sensor, calculate motor speed using the angle sensor, and obtain input signals from the pressure sensor and pedal sensor. After operating these sensors, the MCU transmits the sensor's return data back to the upper-layer application interface via Ethernet communication. This data can be used, in particular, for vehicle diagnostics.

[0057] like Figure 3 As shown in the figure, the system mind map of the intelligent braking method supporting in-vehicle Ethernet includes the following:

[0058] CAN communication: The present invention uses three CAN transceivers, and each CAN communication supports the communication formats of standard frames and extended frames, that is, each CAN has the function of CANFD, thereby realizing high-speed data transmission of CAN communication.

[0059] In-vehicle Ethernet: The Ethernet function uses the MII mode and transmits data via four data lines. It has a flexible interface design and can achieve 100M data communication. It also integrates UDP communication and TCP client / server communication protocols at the application layer, which can meet the transmission of a variety of basic Ethernet data frames.

[0060] Brushless DC motor: The motor pre-driver chip of the present invention adopts Infineon's TLE9180 chip, which has multiple safety protection mechanisms, including over-temperature, over-current, short-circuit and other detection mechanisms. The motor adopts an efficient SPWM control algorithm, which can achieve precise control of the motor speed. The speed can be customized to make the motor rotate stably at this speed, and the speed can reach more than 20 revolutions per second.

[0061] Sensors: Multiple sensors are used in the present invention, including pressure sensors, pedal sensors, and angle sensors. The use of these sensors is mainly for more precise control or participation in the control of the motor. The pressure sensor collects and analyzes the SENT signal, which can greatly improve the sensor's collection accuracy; and the angle sensor uses differential analog signals to avoid interference from other signals to ensure that the collected angle is accurate enough.

[0062] Solenoid valve control: The present invention uses a self-adjustable PWM wave to control the solenoid valve. By controlling the duty cycle and period of the PWM wave, the solenoid valve current is controlled to ensure that solenoid valves with different currents can work normally at the same time. Then, by controlling the operation of the solenoid valve and combining with the rotation of the motor, the brake fluid flows into the wheel cylinder to ultimately generate braking force.

[0063] Specifically, the configuration of the Ethernet hardware initialization environment is to achieve 100M communication rate, MII communication mode, standard MAC layer subtype, MAC address and ring queue buffer setting on the basis of MCAL. The LWIP protocol is transplanted on the Ethernet data link layer to initialize Ethernet with software after the hardware environment is ready, and the LWIP protocol is transplanted to encapsulate the data frames transmitted by Ethernet, and associate the local IP address, mask and gateway. The addition of TCP and UDP application layer protocols is to realize the data transmission function of Ethernet based on TCP and UDP.

[0064] Specifically, the PHY chip obtains a reference clock through an external crystal oscillator and obtains power through an external circuit. The connection with the MCU is that the MCU is connected to corresponding pins of the PHY chip by configuring corresponding pin modes.

[0065] Regarding Ethernet hardware implementation, the braking system uses the S32K344 chip, which supports Ethernet communication. However, the chip lacks a physical physical layer (PHY) chip. This is a common integration method used by many MCU chips: to reduce the burden on the MCU, the PHY chip is placed in a peripheral circuit connected to the MCU. The PHY chip primarily processes the Ethernet physical layer, such as signal decoding and encoding, which is essential for Ethernet communication. Therefore, integrating a PHY chip into a peripheral circuit is a challenge in Ethernet communication. The PHY chip selected for this invention is the TJA1101B, which offers high performance, low power consumption, and a comprehensive safety detection mechanism.

[0066] Specifically, the corresponding pins of the PHY chip are the MDC pin for synchronous data transmission, the MDIO pin for configuring the chip, four pairs of Tx and Rx pins for sending and receiving, the TXC and RXC pins for providing data transmission clock, and the RXER pin for outputting error status.

[0067] like Figure 4 The circuit diagram of a braking system supporting in-vehicle Ethernet-based intelligent braking includes the following: The PHY chip uses an external crystal oscillator to provide a 24MHz reference clock, and an external circuit provides a 3.3V power supply. The MCU connects to the corresponding pins on the PHY chip by configuring the corresponding pin mode. The PHY chip is enabled via the EN pin. The MCU provides a reference clock to the MDC pin for synchronized data transmission, and the PHY chip is configured using the MDIO pin. Because this braking system uses 100M Ethernet in MII mode, the PHY provides four pairs of transmit and receive pins (Tx and Rx). The MCU provides the data transmission clock via TXC and RXC. Under 100M Ethernet, data is transmitted simultaneously on four data lines, each at a rate of 25MHz. The PHY chip connects to external devices via TxR_P and TxR_M, as shown in the lower right circuit diagram above. The PHY chip also outputs error status to the MCU via the RXER pin, and the cause of communication errors can be determined by monitoring the PHY's internal registers. This greatly improves the maintainability of Ethernet communication in this system.

[0068] Specifically, the PWM duty cycle of the control end is changed through the table amplitude of the sine table, the sampling point is set for the modulated sine wave to select the SPWM asymmetric rule, and the sine table is listed for the PWM wave duty cycle using the expected voltage of the sampling point, so that the PWM wave duty cycle is updated using the sine table in each calling cycle; the speed closed loop is added to use the scheduling coefficient for control, and a proportional coefficient is set according to the error between the actual speed and the expected speed to adjust the speed, and the speed is adjusted by changing the whole wave period.

[0069] In traditional automobile braking systems, the electronic control unit is mainly used to adjust the current and voltage of the motor to drive the rotation of the motor and generate braking force. Its implementation principle is mainly to directly control the PWM wave output by the MCU to act on the motor, and directly affect the current and voltage of the motor through the change of the duty cycle. However, this method is not efficient enough to drive the motor, and the controlled motor will be unstable at low speed or even lose step. Therefore, the present invention specifically uses the self-developed SPWM algorithm for control in the motor control algorithm.

[0070] The asymmetric regular sampling formula in the SPWM algorithm is:

[0071] Ton1=(1+M*sin(pi*k / N))*Tc / 4[k=0,2,4,6...2N-2]

[0072] Ton2=(1+M*sin(pi*k / N))*Tc / 4[k=1,3,5,7...2N-1]

[0073] Ton=Ton1+Ton2

[0074] Wherein, Ton1 and Ton2 are the comparison positions of each sampling point of the modulated sine wave and the carrier, Ton is the PWM period to be set, Tc is a complete period of the carrier, M is the set modulation coefficient, and N is the number of set sampling points;

[0075] Among them, in the present invention, in order to adapt to the library function of MCAL, the modulation coefficient M is set to 1, Tc is set to the value corresponding to the full duty cycle, and the sampling point N is set to 4500. When the sampling point N is set to be large enough, the modulated sine wave will be smooth enough.

[0076] The sinusoidal relationship between the motor speed and modulation in the speed closed loop is:

[0077] Speed = Ts / k [k = 4.494]

[0078] Among them, the upper and lower limits of the speed are limited by this proportional relationship in the speed closed loop, further reducing the calculation error in the speed closed loop.

[0079] The above steps use a device for intelligent braking supporting in-vehicle Ethernet, characterized in that the device includes: a CAN transceiver, a brushless DC motor, a sensor, an MCU chip, and a PHY chip. The CAN transceiver is used to send and receive data on the CAN bus, the brushless DC motor is used to convert electrical energy into mechanical energy, the sensor is used to detect physical quantities of the environment or objects and convert them into electrical signals, the MCU chip is used to support Ethernet communication, and the PHY chip is used to implement Ethernet communication at the physical layer.

[0080] An electronic device used in the above steps is characterized in that it includes: an MCU chip and a PHY chip, the MCU chip is used to support Ethernet communication, and the PHY chip is used to process the Ethernet physical layer, wherein the Ethernet communication and processing implement any step of the intelligent braking method supporting vehicle-mounted Ethernet.

[0081] In summary, the present invention retains the traditional CAN communication and adds a 100M vehicle-mounted Ethernet, which greatly improves the data transmission rate of the braking system with the upper layer, so that it can fully meet the data transmission rate requirements of modern braking systems. The addition of Ethernet to the braking system can enable the control unit to transmit data in real time, respond to the driver's operation more quickly, and improve the safety of the vehicle. Since Ethernet provides a higher data bandwidth, the present braking system can transmit a large amount of data in a short time, and the use of Ethernet can improve the overall integration of the braking system. When the Ethernet software was written, the LWIP communication protocol was transplanted and the application layer protocols of UDP and TCP were integrated to flexibly respond to various network environments. The use of Ethernet also makes the upgrade and maintenance of the present braking system more convenient, and the performance of the system can be improved only through software without replacing the hardware. The Ethernet used in the present braking system is a widely standardized technology, which enables the present invention to have the ability to interoperate with equipment from different manufacturers.

[0082] The braking force provided by the present invention is entirely derived from the motor, without adding the driver's braking force on the pedal. This effectively addresses the problem of insufficient braking force and reduces frictional losses between the brake pedal and the brake assembly. The motor control utilizes an SPWM algorithm, which enables the braking system to directly drive the motor without relying on a position sensor. The algorithm is implemented using a sine table, allowing the PWM duty cycle of the control terminal to be varied by looking up the amplitude in the table. This method improves algorithm execution efficiency, shortens execution time, and increases system resource utilization. The algorithm also implements a closed-loop speed control mechanism, ensuring smoother and more stable motor rotation. The speed can be customized, gradually varying and stabilizing the motor speed according to the algorithm's closed-loop control. The algorithm features an adjustable control proportional coefficient, which in turn modifies the duty cycle of the PWM wave in the motor's half-bridge circuit gate, thereby adjusting the motor's control force. A larger proportional coefficient increases the motor's driving force, enhancing the motor's load capacity. This algorithm eliminates the need to rely on specific hardware support, greatly reducing hardware design costs, improving system maintainability and scalability, and allowing the motor's rotation to be affected directly by adjusting the algorithm's software design.

[0083] The embodiments of the present application have been described above. The above description is illustrative and not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is selected to best explain the principles of the embodiments, their practical applications, or improvements to the technology in the market, or to enable other persons skilled in the art to understand the embodiments disclosed herein.

Claims

1. An intelligent braking method supporting vehicle Ethernet, characterized in that: include: Develop according to MCAL, configure the Ethernet hardware initialization environment, transplant the LWIP protocol on the Ethernet data link layer, add TCP and UDP application layer protocols, and realize Ethernet communication functions; Build hardware facilities based on the MCU chip, install the PHY chip in the peripheral circuit and connect it to the MCU to obtain Ethernet physical layer processing capabilities; The SPWM algorithm is used for motor algorithm control. The PWM duty cycle of the control end is changed by the amplitude of the sine table. The motor speed is controlled by the duty cycle. A speed closed loop is added and the scheduling coefficient is used for control.

2. The intelligent braking method supporting vehicle Ethernet according to claim 1, characterized in that: The development is based on MCAL, configuring the Ethernet hardware initialization environment, transplanting the LWIP protocol on the Ethernet data link layer, adding TCP and UDP application layer protocols, and realizing Ethernet communication functions, including: The configuration of the Ethernet hardware initialization environment is to achieve 100M communication rate, MII communication mode, standard MAC layer subtype, MAC address and ring queue buffer settings based on MCAL; The LWIP protocol is transplanted on the Ethernet data link layer to initialize the Ethernet with software after the hardware environment is ready, and the LWIP protocol is transplanted to encapsulate the data frames transmitted by the Ethernet, and associate the local IP address, mask and gateway; The addition of TCP and UDP application layer protocols is to realize the data transmission function of Ethernet based on TCP and UDP.

3. The intelligent braking method supporting vehicle Ethernet according to claim 1, characterized in that: The hardware facilities are built based on the MCU chip, and the PHY chip is installed in the peripheral circuit and connected to the MCU to obtain the Ethernet physical layer processing capabilities, including: The PHY chip obtains a reference clock through an external crystal oscillator and obtains power through an external circuit; The connection with the MCU is that the MCU is connected to the corresponding pins of the PHY chip by configuring the corresponding pin mode.

4. The intelligent braking method supporting vehicle Ethernet according to claim 1, characterized in that: The SPWM algorithm is used to control the motor algorithm, and the PWM duty cycle of the control end is changed by the table amplitude of the sine table. The motor speed is controlled by the duty cycle, and a speed closed loop is added, and the scheduling coefficient is used for control, including: The PWM duty cycle of the control end is changed by the table amplitude of the sine table, a sampling point is set for the modulated sine wave to select the SPWM asymmetric rule, and the sine table is listed for the PWM wave duty cycle using the expected voltage at the sampling point, so as to update the PWM wave duty cycle using the sine table in each call cycle; The added speed closed loop uses a scheduling coefficient for control, and a proportional coefficient is set for the error between the actual speed and the expected speed to adjust the speed. The speed is adjusted by changing the whole wave period.

5. The intelligent braking method supporting vehicle Ethernet according to claim 3, characterized in that: The connecting with the MCU is to connect the MCU to the corresponding pins of the PHY chip by configuring the corresponding pin mode, including: The corresponding pins of the PHY chip are the MDC pin for synchronous data transmission, the MDIO pin for configuring the chip, four pairs of Tx and Rx pins for sending and receiving, the TXC and RXC pins for providing data transmission clock, and the RXER pin for outputting error status.

6. The intelligent braking method supporting vehicle Ethernet according to claim 4, characterized in that: The asymmetric regular sampling formula is: Ton1=(1+M*sin(pi*k / N))*Tc / 4[k=0,2,4,6...2N-2] Ton2=(1+M*sin(pi*k / N))*Tc / 4[k=1,3,5,7...2N-1] Ton=Ton1+Ton2 Ton1 and Ton2 are the comparison positions of each sampling point of the modulated sine wave and the carrier, Ton is the PWM period to be set, Tc is a complete period of the carrier, M is the set modulation coefficient, and N is the number of set sampling points; The sinusoidal relationship between the motor speed and modulation in the speed closed loop is: Speed = Ts / k [k = 4.494].

7. The intelligent braking method supporting vehicle Ethernet according to claim 1, wherein: While introducing Ethernet communication, multi-channel CAN communication is retained; The Ethernet function uses MII mode and can use four data lines for data transmission.

8. A device for intelligent braking supporting vehicle Ethernet, characterized in that: The device comprises: a CAN transceiver, a brushless DC motor, a sensor, an MCU chip and a PHY chip.

9. The intelligent braking device supporting in-vehicle Ethernet according to claim 8, characterized in that: The CAN transceiver is used to send and receive data on the CAN bus, the brushless DC motor is used to convert electrical energy into mechanical energy, the sensor is used to detect the physical quantity of the environment or objects and convert it into electrical signals, the MCU chip is used to support Ethernet communication, and the PHY chip is used to implement Ethernet communication at the physical layer.

10. An electronic device, characterized in that: include: An MCU chip and a PHY chip, wherein the MCU chip is used to support Ethernet communication, and the PHY chip is used to process the Ethernet physical layer, wherein the Ethernet communication and processing implement the steps of the intelligent braking method supporting vehicle Ethernet as described in any one of claims 1 to 7.

Images