A new energy automobile steering system IGBT protection method, system and device

Abstract

The application provides a new energy automobile steering system IGBT protection method, system and equipment, the method comprises the following steps: when starting the new energy automobile, the DC / DC converter working state and the battery voltage U are obtained; it is judged that U is greater than or equal to the normal voltage U0 of the battery; U is greater than or equal to U0, the steering control is started, U is less than U0, it is judged that U is greater than or equal to U1; U is greater than or equal to U1, it is judged whether the DC / DC converter working state is normal; if yes, the steering control is started; if no, an alarm signal is output, and shutdown processing is carried out; U is less than U1, and the new energy automobile cannot be started; wherein U1 is the minimum voltage meeting the IGBT driving capacity provided.The method obtains corresponding information through the CAN network when starting the new energy automobile and after starting the steering control, interval and condition judgment are carried out on the obtained information; corresponding actions are executed according to the judgment result.The new energy automobile steering control IGBT failure problem under different working conditions is solved, and the parts are protected from failure and the driving safety is protected.

Description

Technical Field

[0001] This invention relates to the field of new energy vehicle safety, specifically to a method, system, and device for protecting the IGBT of a new energy vehicle steering system. Background Technology

[0002] Electric power steering (EPS) systems use the power generated by an electric motor to assist the driver in power steering. They typically consist of a torque (steering) sensor, a motor controller, a motor, a reducer, a mechanical steering gear, and a battery. EPS improves a vehicle's handling performance, making the steering wheel lighter and easier to control. When the car turns, the steering sensor detects the torque of the steering wheel and the direction of steering, sending the signal to the electronic control unit (ECU) via a data bus. The ECU then sends an action command to the motor controller based on the transmitted torque and steering direction, causing the motor to output the corresponding steering torque, thus generating power steering. The controller's energy comes from a high-voltage battery pack. Internally, the motor controller uses a control chip, drive circuit, and IGBTs, employing control algorithms to convert direct current (DC) into alternating current (AC), which is then output to the motor to generate torque. The drive circuit converts the battery power into the driving voltage for the IGBTs, enabling them to operate in a switching state. Existing IGBT protection methods for new energy vehicle steering systems rely on external power sources for high voltage after the vehicle's battery is severely depleted. However, when the external power source is removed, the DC / DC converter operates in constant current mode and cannot provide normal voltage to the vehicle's low-voltage electrical components in a short period. During vehicle operation, if the DC / DC converter fails, the vehicle's low-voltage electrical components rely entirely on the battery, consuming a large amount of energy and causing the battery voltage to drop. Simultaneously, during vehicle operation, a sudden low-voltage load can cause a momentary drop in the power supply voltage to the steering motor controller. When the steering motor controller's power supply voltage falls below a certain threshold U1, this value is insufficient to provide the drive circuit with the necessary voltage to operate the IGBT in its on / off state. This causes the IGBT to operate in the desaturation region, significantly increasing power loss and potentially leading to burnout. This can result in either failure to apply high voltage or, in severe cases, failure of the steering control circuit, leading to serious safety accidents. Summary of the Invention

[0003] In view of the shortcomings of the prior art described above, the present invention provides a method, system and device for protecting IGBTs in the steering system of new energy vehicles to solve the above-mentioned technical problems.

[0004] This invention provides a method for protecting IGBTs in the steering system of new energy vehicles, the method comprising the following steps:

[0005] S110: When starting a new energy vehicle, obtain the operating status of the DC / DC converter and the battery voltage U;

[0006] S120: Determine whether the battery voltage U is greater than or equal to the normal battery voltage U0; if yes, proceed to S150; if no, proceed to S130.

[0007] S130: Determine if the battery voltage U is greater than or equal to U1; if yes, proceed to S140; if no, the new energy vehicle cannot start; where U1 is the minimum voltage required to provide IGBT drive capability.

[0008] S140: Determine if the DC / DC converter is operating normally; if yes, proceed to S150; if no, proceed to S160.

[0009] S150: The steering motor controller initiates steering control;

[0010] S160: The steering motor controller outputs an alarm signal and stops the machine.

[0011] In one embodiment of the present invention, after the steering motor controller initiates steering control, the method further includes:

[0012] S210: Obtain the operating status of the DC / DC converter, the battery voltage U, and the driving speed V of the new energy vehicle;

[0013] S220: Determine whether the battery voltage U is greater than or equal to the normal battery voltage U0; if yes, proceed to S270; if no, proceed to S230.

[0014] S230: Determine if the battery voltage U is greater than or equal to U1; if yes, proceed to S240; if no, proceed to S250.

[0015] S240: Determine if the DC / DC converter is operating normally; if yes, proceed to S270; if no, proceed to S280.

[0016] S250: Determine if the current driving speed V is less than or equal to V0; if yes, proceed to S260; if no, proceed to S280; where V0 is the safe speed at which the steering controller can be directly turned off;

[0017] S260: The steering motor controller outputs a reminder message and disables steering control;

[0018] S270: The steering motor controller maintains the steering control initiation;

[0019] S280: The steering motor controller outputs a reminder message and limits the vehicle's power.

[0020] In one embodiment of the present invention, the DC / DC converter operating status, battery voltage U, and current driving speed V are obtained from the CAN network.

[0021] In one embodiment of the present invention, the alarm signal and the reminder information are displayed via a vehicle infotainment system.

[0022] The present invention also provides an IGBT protection system for a new energy vehicle steering system, the system comprising:

[0023] Information acquisition module: Acquires the operating status of the DC / DC converter, battery voltage U, and vehicle speed V of the new energy vehicle;

[0024] Judgment module: Performs range and condition judgments on the operating status of DC / DC converter, battery voltage U, and vehicle speed V of new energy vehicle;

[0025] Execution module: Executes the corresponding action based on the judgment result.

[0026] The present invention also provides an electronic device, the electronic device comprising:

[0027] One or more processors;

[0028] A storage device is provided for storing one or more programs, which, when executed by one or more processors, enable the electronic device to implement an IGBT protection method for a new energy vehicle steering system as described in any of the above embodiments.

[0029] The beneficial effects of this invention are as follows: This invention obtains the operating status of the DC / DC converter, battery voltage U, and current driving speed V via the CAN network when starting a new energy vehicle and after the steering motor controller initiates steering control. It then performs range and conditional judgments on the DC / DC converter operating status, battery voltage U, and new energy vehicle speed V; and executes corresponding actions based on the judgment results. This solves the problem that when the power supply voltage of the steering motor controller is lower than a certain threshold U1, this value is insufficient to support the drive circuit to provide the IGBT with the driving voltage to operate in the on / off state, causing the IGBT to operate in the desaturation region, resulting in a significant increase in power loss and potential burn-out. This invention balances protecting components from failure and ensuring driving safety.

[0030] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings:

[0032] Figure 1 A flowchart illustrating an exemplary embodiment of the present invention is provided, showing a method for protecting the IGBT of a new energy vehicle steering system when starting a new energy vehicle;

[0033] Figure 2 A flowchart illustrating an exemplary embodiment of the present invention is shown below, illustrating an IGBT protection method for a new energy vehicle steering system after the steering motor controller initiates steering control;

[0034] Figure 3 This is a schematic diagram of the IGBT protection system structure of a new energy vehicle steering system, as shown in an exemplary embodiment of the present invention. Detailed Implementation

[0035] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0036] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0037] In the following description, numerous details are explored to provide a more thorough explanation of embodiments of the invention. However, it will be apparent to those skilled in the art that embodiments of the invention may be practiced without these specific details. In other embodiments, well-known structures and devices are shown in block diagram form rather than in detail to avoid obscuring embodiments of the invention.

[0038] First, it's important to understand that Electric Power Steering (EPS) uses power generated by an electric motor to assist the driver in steering. It typically consists of a torque (steering) sensor, a motor controller, a motor, a reducer, a mechanical steering gear, and a battery. EPS improves a car's handling performance, making the steering wheel lighter and easier to control. When the car turns, the steering sensor detects the torque of the steering wheel and the direction of steering, sending the signal to the electronic control unit (ECU) via a data bus. The ECU then sends a command to the motor controller based on the torque and steering direction, causing the motor to output the appropriate steering torque, thus generating power steering. The controller's energy comes from a high-voltage battery pack. Internally, the motor controller uses a control chip, drive circuit, and IGBTs to convert direct current (DC) into alternating current (AC) using a control algorithm, which is then output to the motor to generate torque. The drive circuit converts the battery power into the driving voltage for the IGBTs, enabling them to operate in a switching state.

[0039] Figure 1 A flowchart illustrating an exemplary embodiment of the present invention is provided, showing a method for protecting the IGBT of a new energy vehicle steering system when starting a new energy vehicle;

[0040] like Figure 1 As shown, the present invention provides an IGBT protection method for a new energy vehicle steering system, applied to a steering motor controller. The method includes the following steps:

[0041] Step S110: When starting the new energy vehicle, obtain the operating status of the DC / DC converter and the battery voltage U;

[0042] Step S120: Determine whether the battery voltage U is greater than or equal to the normal battery voltage U0; if yes, proceed to S150; if no, proceed to S130.

[0043] Step S130: Determine whether the battery voltage U is greater than or equal to U1; if yes, proceed to S140; if no, the new energy vehicle cannot start; where U1 is the minimum voltage required to provide IGBT drive capability.

[0044] Step S140: Determine if the DC / DC converter is operating normally; if yes, proceed to S150; if no, proceed to S160.

[0045] Step S150: The steering motor controller initiates steering control;

[0046] Step S160: The steering motor controller outputs an alarm signal and performs a shutdown procedure.

[0047] Specifically, the input voltage collected by the steering motor controller is divided into three intervals. The battery voltage is denoted as U, the normal battery voltage is denoted as U0, and the lowest voltage that can meet the IGBT driving ability is denoted as U1. Obviously, U1 < U0. Here, U0 and U1 can be defined as one sampling value or the average value of several consecutive sampling values. The DCDC state is divided into a normal working state and an abnormal working state. In the normal working state, the battery can be charged after the high voltage is applied. On the contrary, in the abnormal working state, the battery cannot be charged. The alarm signal is displayed through the vehicle computer.

[0048] When starting a new energy vehicle, the logic of an IGBT protection method for the steering system of a new energy vehicle is as follows: When starting a new energy vehicle, when the steering motor controller first obtains the start signal, it obtains the battery voltage U and the working state of the DC / DC converter (DC / DC) from the CAN network to determine whether to start the steering control. The judgment logic is as follows:

[0049] 1. When receiving the start signal and detecting that U ≥ U0, start the steering control.

[0050] 2. When receiving the start signal and detecting that U1 ≤ U < U0, if the DCDC working state is normal, the steering motor controller starts the steering control. If the DCDC working state is abnormal, the steering motor controller outputs an alarm signal and performs a shutdown process.

[0051] 3. When receiving the start signal and detecting that U < U1, the vehicle cannot start.

[0052] Figure 2 The flowchart of an IGBT protection method for the steering system of a new energy vehicle shown in an exemplary embodiment of the present invention after the steering motor controller starts the steering control;

[0053] As Figure 2 shown, for an IGBT protection method for the steering system of a new energy vehicle provided by the present invention, after the steering motor controller starts the steering control, the method further includes:

[0054] Step S210: Obtain the working state of the DC / DC converter, the battery voltage U, and the driving speed V of the new energy vehicle;

[0055] Step S220: Determine whether the battery voltage U is greater than or equal to the normal battery voltage U0; if so, enter S270; if not, enter S230;

[0056] Step S230: Determine whether the battery voltage U is greater than or equal to U1; if so, enter S240; if not, enter S250;

[0057] Step S240: Determine whether the working state of the DC / DC converter is normal; if yes, proceed to S270; if no, proceed to S280;

[0058] Step S250: Determine whether the current driving speed V is less than or equal to V0; if yes, proceed to S260; if no, proceed to S280; where V0 is the safe vehicle speed at which the steering controller can be directly turned off;

[0059] Step S260: The steering motor controller outputs a reminder message and turns off the steering control;

[0060] Step S270: The steering motor controller keeps the steering control started;

[0061] Step S280: The steering motor controller outputs a reminder message and limits the vehicle power.

[0062] Specifically, during the vehicle driving process, in case of abnormal low-voltage power-off, define the vehicle speed at which the steering controller can be directly turned off as the safe vehicle speed, denoted as V0; where V0 can be defined as one sampling value or the average value of several consecutive sampling values.

[0063] The logic of an IGBT protection method for a new energy vehicle steering system after starting the steering control is as follows: After the new energy vehicle starts the steering motor controller, obtain the battery voltage U, the working state of the DC / DC converter (DC / DC), and the driving speed V of the new energy vehicle from the CAN network for monitoring. The monitoring logic is as follows:

[0064] 1. When it is detected that U≥U0, keep the steering control started.

[0065] 2. When it is detected that U1≤U<U0 and the DCDC working state is normal, keep the steering control started; when the DC / DC working state is abnormal, the steering motor controller outputs a reminder message and limits the vehicle power;

[0066] 3. When U<U1, if the driving speed V of the new energy vehicle is ≤V0, the steering motor controller outputs a reminder message and turns off the steering control. If the driving speed V of the new energy vehicle is >V0, the steering motor controller outputs a reminder message and limits the vehicle power.

[0067] Preferably, by limiting the vehicle power, the driving speed V of the new energy vehicle slowly decreases. When the driving speed V drops to V0, the steering motor controller outputs a reminder message and turns off the steering control.

[0068] In one exemplary embodiment, the DC / DC converter operating status, battery voltage U, and current driving speed V are obtained from the CAN network. Controller Area Network (CAN) is a serial communication protocol commonly used in vehicle and industrial automation control systems, characterized by high reliability, high real-time performance, and high bandwidth. The CAN network is primarily used for communication between different components, such as the engine control unit, braking system, transmission system, and instrument panel in a vehicle. These components communicate with each other through the CAN network, enabling coordinated operation. The CAN network allows for real-time acquisition of the DC / DC converter operating status, battery voltage, and current driving speed information, enabling timely detection of electronic system anomalies and preventing situations where the vehicle cannot start or drive due to electronic system failures.

[0069] In one exemplary embodiment, the alarm signal and the reminder information are displayed via the vehicle's infotainment system. Displaying the alarm signal and reminder information via the vehicle's infotainment system helps the driver understand the vehicle's status and driving conditions more promptly, improving driving safety. When the steering motor controller malfunctions or experiences an abnormality, the vehicle's infotainment system will promptly display the alarm signal and reminder information, alerting the driver to the status of the steering motor controller. Simultaneously, the vehicle's display interface is clear and easy to understand, facilitating driver operation and settings, improving driver efficiency, enhancing driver awareness and vigilance, and reducing the occurrence of traffic accidents.

[0070] Figure 3 A schematic diagram of an IGBT protection system for a new energy vehicle steering system is shown as an exemplary embodiment of the present invention.

[0071] like Figure 3 As shown, this exemplary IGBT protection system for a new energy vehicle steering system includes:

[0072] Information acquisition module 301: Acquires the operating status of the DC / DC converter, the battery voltage U, and the vehicle speed V of the new energy vehicle;

[0073] Judgment module 302: performs interval and condition judgments on the operating status of the DC / DC converter, the battery voltage U, and the driving speed V of the new energy vehicle;

[0074] Execution module 303: Executes the corresponding action based on the judgment result.

[0075] It should be noted that the IGBT protection system for a new energy vehicle steering system provided in the above embodiments and the IGBT protection method for a new energy vehicle steering system provided in the above embodiments belong to the same concept. The specific operation methods of each module and unit have been described in detail in the method embodiments and will not be repeated here. In practical applications, the IGBT protection system for a new energy vehicle steering system provided in the above embodiments can be assigned to different functional modules as needed, that is, the internal structure of the system can be divided into different functional modules to complete all or part of the functions described above. This is not a limitation here.

[0076] Embodiments of this application also provide an electronic device, including: one or more processors; and a storage device for storing one or more programs, which, when executed by the one or more processors, cause the electronic device to implement the IGBT protection method for a new energy vehicle steering system provided in the above embodiments.

[0077] Specifically, according to embodiments of this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program including a computer program for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication component, and / or installed from a removable medium. When the computer program is executed by a central processing unit (CPU), it performs various functions defined in the system of this application.

[0078] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functions, and operations that may be implemented in systems and methods according to various embodiments of this application. Each block in a flowchart or block diagram may represent a module, segment, or portion of code, which contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram or flowchart, and combinations of blocks in a block diagram or flowchart, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0079] The units described in the embodiments of this application can be implemented in software or hardware, and the described units can also be located in a processor. The names of these units do not necessarily limit the specific unit itself.

[0080] Another aspect of this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the IGBT protection method for a new energy vehicle steering system as described above. This computer-readable storage medium may be included in the electronic device described in the above embodiments, or it may exist independently and not be assembled into the electronic device.

[0081] Another aspect of this application provides a computer program product or computer program including computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the IGBT protection method for a new energy vehicle steering system provided in the above embodiments.

[0082] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A method for protecting IGBTs in a new energy vehicle steering system, applied to a steering motor controller, characterized in that... , The method includes the following steps: S110: When starting a new energy vehicle, obtain the working state of the DC / DC converter and the battery voltage U; S120: Determine whether the battery voltage U is greater than or equal to the normal battery voltage U0; if so, proceed to S150; if not, proceed to S130; S130: Determine whether the battery voltage U is greater than or equal to U1; if so, proceed to S140; if not, the new energy vehicle cannot be started; where U1 is the minimum voltage that satisfies the IGBT driving ability; S140: Determine whether the working state of the DC / DC converter is normal; if so, proceed to S150; if not, proceed to S160; S150: The steering motor controller starts the steering control; S160: The steering motor controller outputs an alarm signal and performs a shutdown process; Where, after the steering motor controller starts the steering control, the method further includes: S210: Obtain the working state of the DC / DC converter, the battery voltage U, and the driving speed V of the new energy vehicle; S220: Determine whether the battery voltage U is greater than or equal to the normal battery voltage U0; if so, proceed to S270; if not, proceed to S230; S230: Determine whether the battery voltage U is greater than or equal to U1; if so, proceed to S240; if not, proceed to S250; S240: Determine whether the working state of the DC / DC converter is normal; if so, proceed to S270; if not, proceed to S280; S250: Determine whether the current driving speed V is less than or equal to V0; if so, proceed to S260; if not, proceed to S280; where V0 is the safe driving speed at which the steering controller can be directly turned off; S260: The steering motor controller outputs a reminder message and turns off the steering control; S270: The steering motor controller maintains the start of the steering control; S280: The steering motor controller outputs a reminder message and limits the vehicle power; Where, the working state of the DC / DC converter, the battery voltage U, and the current driving speed V are obtained from the CAN network; Where, the alarm signal and the reminder message are displayed on the vehicle console; Where, when the new energy vehicle starts, the steering motor controller first obtains the start signal, obtains the battery voltage U and the working state of the DC / DC converter from the CAN network, determines whether to start the steering control, and the judgment logic is as follows: When receiving the start signal and detecting that U≥U0, start the steering control; When receiving the start signal and detecting that U1≤U<U0, if the working state of the DC / DC converter is normal, the steering motor controller starts the steering control; if the working state of the DC / DC converter is abnormal, the steering motor controller outputs an alarm signal and performs a shutdown process; When receiving the start signal and detecting that U<U1, the vehicle cannot be started; Or, after the new energy vehicle starts the steering motor controller, obtain the battery voltage U, the working state of the DC / DC converter, and the driving speed V of the new energy vehicle from the CAN network for monitoring, and the monitoring logic is as follows: When detecting that U≥U0, maintain the start of the steering control; When it is detected that U1 ≤ U < U0, the DC / DC converter is in normal working state, and the steering control startup is maintained; when the DC / DC converter is in abnormal working state, the steering motor controller outputs a reminder message and limits the vehicle power. When U < U1, if the driving speed V of the new energy vehicle is V ≤ V0, the steering motor controller outputs a reminder message and turns off the steering control; if the driving speed V of the new energy vehicle is V > V0, the steering motor controller outputs a reminder message and limits the vehicle power.

2. An IGBT protection system for a new energy vehicle steering system, characterized in that, Applied to the method described in claim 1, the system includes: An information acquisition module: acquires the working state of the DC / DC converter, the battery voltage U, and the driving speed V of the new energy vehicle. A judgment module: makes interval and condition judgments on the working state of the DC / DC converter, the battery voltage U, and the driving speed V of the new energy vehicle. An execution module: executes corresponding actions according to the judgment result.

3. An electronic device, characterized in that, The electronic device includes: One or more processors; A storage device for storing one or more programs, which when executed by the one or more processors, cause the electronic device to implement a method for protecting IGBT of a steering system of a new energy vehicle as described in claim 1.

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