Multifunctional automobile voltage regulator based on CAN bus

Abstract

The invention discloses a multifunctional automobile voltage regulator based on a CAN bus, and the voltage regulator comprises an MCU which is internally integrated with a Bootloader function module, a CAN communication baud rate adaptive adjustment module, and a load response control module. The DC-DC converter is connected to a rectifier bridge of the generator and is used for processing the voltage of the generator and supplying power to other hardware in the regulator; the B + voltage analog-to-digital converter is connected to a rectifier bridge of the generator and is used for dividing the voltage of the generator and inputting the divided voltage into an ADC channel of the MCU, so that the MCU calculates the current voltage of a B + end; the regulator has an LRC function, and when the load suddenly changes from light load to heavy load, the output voltage of the regulator is slowly raised, so that the voltage fluctuation is minimized. Parameters can be set in real time, and a vehicle machine system can set the parameters in the regulator in real time through a CAN bus, such as target voltage, maximum excitation current limitation and the like.

Description

Technical Field

[0001] This invention relates to the field of automotive regulator technology, specifically a multi-functional automotive voltage regulator based on the CAN bus. Background Technology

[0002] Automotive voltage regulators are used to stabilize the output voltage of the vehicle's alternator in order to protect the battery and vehicle electrical components and ensure the stable operation of the vehicle's electrical system.

[0003] Currently, there are two main types of automotive voltage regulators on the market:

[0004] 1. Electronic Automotive Voltage Regulator. This type of regulator is based on transistors or integrated circuits. It has the following drawbacks: Limited functionality, only regulating voltage; inability to communicate (lacking CAN or LIN communication capabilities, unable to feed back the regulator's current status to the vehicle's infotainment system, and unable to receive control commands from the system); inability to freely set the target voltage (this regulator has only one target voltage; setting a different value requires hardware modifications, which are very costly); and inability to upgrade software (this regulator uses hardware to implement all functions without any software, therefore it cannot add or modify functions according to customer needs).

[0005] 2. LIN Bus-Based Automotive Voltage Regulator. This regulator adds LIN communication functionality to the electronic automotive voltage regulator, thus offering the following advantages: Status feedback function: Through the LIN bus, the regulator can feed back the current status to the vehicle's infotainment system, facilitating fault diagnosis. Target voltage can be set: Through the LIN bus, the regulator can receive and set the target voltage from the vehicle's infotainment system without requiring hardware circuit modifications, significantly reducing costs.

[0006] However, LIN bus-based automotive voltage regulators also have the following problems: Software cannot be upgraded; current LIN bus-based regulators on the market lack a bootloader function, thus preventing software upgrades. Communication is susceptible to interference; LIN bus is a single-bus communication method, easily affected by interference in the complex electromagnetic environment of a car, leading to communication abnormalities.

[0007] To address this, a multi-functional automotive voltage regulator based on the CAN bus is proposed. Summary of the Invention

[0008] The purpose of this invention is to provide a multi-functional automotive voltage regulator based on a CAN bus to solve the problems mentioned in the background art.

[0009] To achieve the above objectives, the present invention provides the following technical solution: a multi-functional automotive voltage regulator based on a CAN bus, comprising:

[0010] The MCU integrates a bootloader module, a CAN communication baud rate adaptive adjustment module, and a load response control module.

[0011] A DC-DC converter, connected to the rectifier bridge of the generator, is used to process the generator's voltage and power other hardware in the regulator.

[0012] The B+ voltage analog-to-digital converter is connected to the rectifier bridge of the generator. It is used to divide the generator voltage and input it into the ADC channel of the MCU, so that the MCU can calculate the current voltage at the B+ terminal.

[0013] A CAN transceiver is used to connect to the CAN bus on a car and to communicate with the vehicle's infotainment system.

[0014] The phase frequency / voltage detection module is connected to the three-phase terminals of the generator. It is used to process the generator voltage and input it into the MCU to calculate the current speed of the generator and determine whether the phase voltage is in a normal state.

[0015] The MOSFET driver is connected to the F terminal of the generator. By switching the MOSFET on and off, the magnitude of the excitation current at the F terminal is controlled, thereby controlling the output voltage of the generator.

[0016] The current analog-to-digital converter is connected to the F terminal of the generator and obtains the magnitude of the current excitation current at the F terminal through a current sampling circuit.

[0017] Preferably, the Bootloader module transmits the new firmware version in chunks to the regulator via the CAN bus using the Ymodem protocol to replace the old firmware. Specifically:

[0018] The host computer splits the 128-byte firmware data into 5-byte sub-data blocks and transmits them to the regulator via the CAN bus. The regulator receives the data and reassembles it into a complete 128-byte data frame to replace the old firmware.

[0019] Preferably, the CAN communication baud rate adaptive adjustment module is used by the regulator to automatically adjust its own CAN communication baud rate according to the currently connected CAN bus, so that it can communicate with other ECUs on the CAN bus. The specific working method includes the following steps:

[0020] S1. The regulator is powered on and reads the historical baud rate configuration stored in the EEPROM;

[0021] S2. If a historical baud rate configuration exists, set the CAN communication baud rate to that value; otherwise, set it to 250Kbps by default.

[0022] S3. Send a test data packet to the CAN bus;

[0023] S4. Read the CAN status register and determine whether the communication status is STATUS_SUCCESS;

[0024] S5. If the result is successful, increment success_counter by 1 and clear failure_counter. If the result is unsuccessful, increment failure_counter by 1 and clear success_counter.

[0025] S6. When success_counter≥10, confirm that the current baud rate matches and jump to the APP program. When fail_counter≥10, switch to another baud rate and write the baud rate configuration to EEPROM.

[0026] Preferably, the load response control module is used to gradually increase the output voltage when the generator voltage suddenly drops due to a transition from light load to heavy load, thereby minimizing voltage fluctuations. The specific operating method includes the following steps:

[0027] S1. When the voltage at terminal B+ suddenly drops, enter LRC state and record the voltage at terminal B+ at this time. ;

[0028] S2. Assume the time of LRC is... If the time interval is 5 seconds, then the voltage increase every 5 ms can be calculated. ,Right now ;

[0029] S3, Set the target voltage to... Then, using a PI control algorithm, the current voltage is adjusted to... ;

[0030] S4, when reached When, set the target voltage to Continue using the control algorithm to adjust the current voltage to ;

[0031] S5, until the current voltage reaches If so, then exit LRC control.

[0032] Preferably, the vehicle system can set regulator parameters in real time via a CAN transceiver, the parameters including target voltage and maximum excitation current limit.

[0033] Compared with the prior art, the beneficial effects of the present invention are:

[0034] 1. It has an LRC function, which gradually increases the output voltage of the regulator when the load changes abruptly from light load to heavy load, so as to minimize voltage fluctuations.

[0035] 2. Parameters can be set in real time. The vehicle system can set the parameters in the regulator in real time via the CAN bus, such as target voltage and maximum excitation current limit.

[0036] 3. Adaptive adjustment of CAN communication baud rate: When powered on, the regulator will automatically adjust its own CAN communication baud rate according to the baud rate of the currently connected CAN bus. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the regulator of the present invention;

[0038] Figure 2 This is a schematic diagram illustrating the software upgrade of the Bootloader functional module of the present invention;

[0039] Figure 3 This is a schematic diagram illustrating the baud rate adjustment of the CAN communication baud rate adaptive adjustment module of the present invention.

[0040] Figure 4 This is a schematic diagram of the load response control module of the present invention adjusting the target voltage. Detailed Implementation

[0041] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0042] Please see Figure 1-4 This invention provides a technical solution: a multi-functional automotive voltage regulator based on a CAN bus, comprising:

[0043] The MCU integrates a bootloader module, a CAN communication baud rate adaptive adjustment module, and a load response control module.

[0044] A DC-DC converter, connected to the rectifier bridge of the generator, is used to process the generator's voltage and power other hardware in the regulator.

[0045] The B+ voltage analog-to-digital converter is connected to the rectifier bridge of the generator. It is used to divide the generator voltage and input it into the ADC channel of the MCU, so that the MCU can calculate the current voltage at the B+ terminal.

[0046] A CAN transceiver is used to connect to the CAN bus on a car and to communicate with the vehicle's infotainment system.

[0047] The phase frequency / voltage detection module is connected to the three-phase terminals of the generator. It is used to process the generator voltage and input it into the MCU to calculate the current speed of the generator and determine whether the phase voltage is in a normal state.

[0048] The MOSFET driver is connected to the F terminal of the generator. By switching the MOSFET on and off, the magnitude of the excitation current at the F terminal is controlled, thereby controlling the output voltage of the generator.

[0049] The current analog-to-digital converter is connected to the F terminal of the generator and obtains the magnitude of the current excitation current at the F terminal through a current sampling circuit.

[0050] like Figure 1 As shown, it also has the following ports:

[0051] 1. B+ terminal: The B+ terminal connects to the rectifier bridge after the generator. Its specific functions are as follows: The voltage at the B+ terminal is processed by a DC-DC converter and then supplies power to other hardware in the regulator. Alternatively, the voltage at the B+ terminal is processed by a B+ voltage analog-to-digital converter and input to the MCU's ADC channel, allowing the MCU to calculate the current voltage at the B+ terminal.

[0052] 2. P terminal: The P terminal connects to the three-phase terminals of the AC generator and has the following specific functions: The voltage at the P terminal is processed by the phase frequency circuit in the phase frequency / voltage detection module and input to the MCU to calculate the current speed of the generator. The voltage at the P terminal is also processed by the phase voltage circuit in the phase frequency / voltage detection module and input to the MCU to determine whether the phase voltage is in a normal state.

[0053] 3. Terminal F: Terminal F is connected to the F terminal of the AC generator and has the following functions: It controls the magnitude of the excitation current at terminal F by switching the MOSFET on and off, thereby controlling the generator's output voltage. The current sampling circuit in the current-to-digital converter obtains the current magnitude of the excitation current at terminal F.

[0054] 4. CAN_H and CAN_L terminals: The CAN_H and CAN_L terminals are connected to the CAN bus on the vehicle via a CAN transceiver for communication with the vehicle's infotainment system.

[0055] 5. E terminal: The E terminal is connected to the E terminal of the generator and is used together with the B+ terminal to complete the circuit loop.

[0056] like Figure 2As shown, the Bootloader module is used to upgrade the regulator's software. The Bootloader transmits the new firmware in chunks to the regulator via the CAN bus using the Ymodem protocol to replace the old firmware. The specific process is as follows: the minimum length of a data frame in the traditional Ymodem protocol is 128 bytes, while the maximum length of a data frame in the CAN bus is 8 bytes. The host computer splits the 128-byte data into 5-byte chunks and transmits them to the regulator. The regulator then reassembles the received data into a complete 128-byte data frame. Thus, it enables the transmission of large files to the regulator via the CAN bus using the Ymodem protocol, ensuring a stable download of the new firmware.

[0057] like Figure 3 As shown, adaptive CAN communication baud rate adjustment is used by the regulator to automatically adjust its own CAN communication baud rate according to the currently connected CAN bus, enabling it to communicate with other ECUs on the CAN bus. Currently, adaptive switching between 250Kbps and 500Kbps has been implemented, as follows:

[0058] S1. The regulator is powered on and reads the historical baud rate configuration stored in the EEPROM;

[0059] S2. If a historical baud rate configuration exists, set the CAN communication baud rate to that value; otherwise, set it to 250Kbps by default.

[0060] S3. Send a test data packet to the CAN bus;

[0061] S4. Read the CAN status register and determine whether the communication status is STATUS-SUCCESS.

[0062] S5. If the result is successful, increment success_counter by 1 and clear failure_counter. If the result is unsuccessful, increment failure_counter by 1 and clear success_counter.

[0063] S6. When success_counter≥10, confirm that the current baud rate matches and jump to the APP program. When fail_counter≥10, switch to another baud rate and write the baud rate configuration to EEPROM.

[0064] like Figure 4 As shown, the Load Response Control (LRC) module is used to gradually raise the output voltage when the generator voltage suddenly drops due to a transition from light load to heavy load, minimizing voltage fluctuations. The LRC control is implemented using a step-by-step adjustment of the target voltage, as follows:

[0065] S1. When the voltage at terminal B+ suddenly drops, enter LRC state and record the voltage at terminal B+ at this time. .

[0066] S2. Assume the time of LRC is... If the time interval is 5 seconds, then the voltage increase every 5 ms can be calculated. ,Right now .

[0067] S3, Set the target voltage to... Then, using a PI control algorithm, the current voltage is adjusted to... .

[0068] S4, when reached When, set the target voltage to Continue using the control algorithm to adjust the current voltage to .

[0069] S5, until the current voltage reaches If so, then exit LRC control.

[0070] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A multi-functional automotive voltage regulator based on a CAN bus, characterized in that, include: The MCU integrates a bootloader module, a CAN communication baud rate adaptive adjustment module, and a load response control module. A DC-DC converter, connected to the rectifier bridge of the generator, is used to process the generator's voltage and power other hardware in the regulator. The B+ voltage analog-to-digital converter is connected to the rectifier bridge of the generator. It is used to divide the generator voltage and input it into the ADC channel of the MCU, so that the MCU can calculate the current voltage at the B+ terminal. A CAN transceiver is used to connect to the CAN bus on a car and to communicate with the vehicle's infotainment system. The phase frequency / voltage detection module is connected to the three-phase terminals of the generator. It is used to process the generator voltage and input it into the MCU to calculate the current speed of the generator and determine whether the phase voltage is in a normal state. The MOSFET driver is connected to the F terminal of the generator. By switching the MOSFET on and off, the magnitude of the excitation current at the F terminal is controlled, thereby controlling the output voltage of the generator. The current analog-to-digital converter is connected to the F terminal of the generator and obtains the magnitude of the current excitation current at the F terminal through a current sampling circuit.

2. The multi-functional automotive voltage regulator based on CAN bus according to claim 1, characterized in that: The Bootloader module transmits the new firmware in chunks to the regulator via the CAN bus using the Ymodem protocol to replace the old firmware. Specifically: The host computer splits the 128-byte firmware data into 5-byte sub-data blocks and transmits them to the regulator via the CAN bus. The regulator receives the data and reassembles it into a complete 128-byte data frame to replace the old firmware.

3. A multi-functional automotive voltage regulator based on a CAN bus according to claim 1, characterized in that: The CAN communication baud rate adaptive adjustment module is used by the regulator to automatically adjust its own CAN communication baud rate according to the currently connected CAN bus, so that it can communicate with other ECUs on the CAN bus. The specific working method includes the following steps: S1. The regulator is powered on and reads the historical baud rate configuration stored in the EEPROM; S2. If a historical baud rate configuration exists, set the CAN communication baud rate to that value; otherwise, set it to 250Kbps by default. S3. Send a test data packet to the CAN bus; S4. Read the CAN status register and determine whether the communication status is STATUS_SUCCESS; S5. If the result is successful, increment success_counter by 1 and clear failure_counter. If the result is unsuccessful, increment failure_counter by 1 and clear success_counter. S6. When success_counter≥10, confirm that the current baud rate matches and jump to the APP program. When fail_counter≥10, switch to another baud rate and write the baud rate configuration to EEPROM.

4. A multi-functional automotive voltage regulator based on a CAN bus according to claim 1, characterized in that: The load response control module is used to gradually increase the output voltage when the generator voltage suddenly drops due to a transition from light load to heavy load, thereby minimizing voltage fluctuations. The specific operating method includes the following steps: S1. When the voltage at terminal B+ suddenly drops, enter LRC state and record the voltage at terminal B+ at this time. ; S2. Assume the time of LRC is... If the time interval is 5 seconds, then the voltage increase every 5 ms can be calculated. ,Right now ; S3, Set the target voltage to... Then, using a PI control algorithm, the current voltage is adjusted to... ; S4, when reached When, set the target voltage to Continue using the control algorithm to adjust the current voltage to ; S5, until the current voltage reaches If so, then exit LRC control.

5. A multi-functional automotive voltage regulator based on a CAN bus according to claim 1, characterized in that: The vehicle system can set regulator parameters in real time via a CAN transceiver. These parameters include the target voltage and the maximum excitation current limit.

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