Control method for electric drive system, and vehicle and storage medium
By setting a dedicated shutdown signal interface on the drive logic circuit of the electric drive system, the target mode is determined according to the shutdown operation type and a shutdown signal is sent, which solves the problem that the safety shutdown path in the vehicle electric drive system cannot be independently controlled, realizes independent control of the safety shutdown operation, and improves system safety.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- WUXI INFIMOTION PROPULSION TECH CO LTD
- Filing Date
- 2025-10-27
- Publication Date
- 2026-07-23
AI Technical Summary
In the prior art, the safety shutdown path of the vehicle electric drive system cannot be controlled independently, making it difficult to meet the actual safety shutdown control requirements. In particular, when a fault is detected, the control circuit for motor rotation and shutdown is the same, making it impossible to achieve independent safety shutdown control.
A dedicated shutdown signal interface is set on the drive logic circuit of the electric drive system. The target mode is determined according to the type of shutdown operation request, and the corresponding shutdown signal is sent to control the shutdown of the bridge circuit. This increases the control dimension of the interface mode and realizes independent control of different safety shutdown operations.
By using an independent control shutdown signal interface, the system avoids sharing the same path with the drive signal that controls the motor rotation, thus achieving independent control of the safe shutdown operation, reducing the risk of transient current, and improving the system's safety performance.
Smart Images
Figure CN2025130229_23072026_PF_FP_ABST
Abstract
Description
Control methods for electric drive systems, vehicles and storage media
[0001] Related applications
[0002] This application claims priority to Chinese patent application No. 202510078500.5, filed on January 17, 2025, the entire contents of which are incorporated herein by reference.
[0003] Technical Field
[0004] This application relates to the field of motor control technology, and in particular to a control method for an electric drive system, a vehicle, and a storage medium. Background Technology
[0005] In the field of new energy vehicles, safety shutdown (also known as safety shutdown path) is a crucial component of functional safety and the final link in the functional safety chain. After fault detection and identification of safety risks, it plays a vital role in eliminating those risks. Currently, safety shutdown paths for vehicle electric drive systems (especially the functional monitoring layer shutdown path), i.e., L2 layer shutdown paths, can be mainly divided into three types: High-side Active Short Circuit (HASC), Low-side Active Short Circuit (LASC), and complete shutdown. However, current shutdown schemes implementing these three methods primarily achieve shutdown through the control circuitry that drives the motor in the electric drive system when a fault is detected. This means that controlling motor rotation and controlling shutdown share the same control circuitry, making independent control of safety shutdown impossible and failing to meet the actual control requirements of safety shutdown.
[0006] The above content is only used to help understand the technical solution of this application and does not represent an admission that the above content is prior art. Summary of the Invention
[0007] This application proposes a control method for an electric drive system, the electric drive system including a drive logic circuit and a bridge circuit, the drive logic circuit being provided with a disconnect signal interface, and the control method for the electric drive system including:
[0008] Upon receiving a shutdown operation request, the target mode of the shutdown signal interface is determined based on the type of shutdown operation corresponding to the shutdown operation request.
[0009] Maintain or adjust the interface mode of the shutdown signal interface to the target mode, and send a shutdown signal corresponding to the shutdown operation request to the shutdown signal interface in the target mode, so that the driving logic circuit controls the shutdown of the bridge circuit based on the shutdown signal.
[0010] In one embodiment, when the shutdown operation type is a half-bridge arm active short circuit, the target mode of the shutdown signal interface is a pulse width modulation mode. The step of maintaining or adjusting the interface mode of the shutdown signal interface to the target mode and sending a shutdown signal corresponding to the shutdown operation request to the shutdown signal interface in the target mode includes:
[0011] When the type of shutdown operation corresponding to the shutdown operation request is half-bridge arm active short circuit, the interface mode of the shutdown signal interface is maintained or adjusted to pulse width modulation mode.
[0012] A pulse shutdown signal with a gradually changing duty cycle is sent to the shutdown signal interface in the pulse width modulation mode, so that the driving logic circuit performs soft control of the bridge circuit to actively short-circuit half-bridge arms based on the pulse shutdown signal with the gradually changing duty cycle. The soft control is to gradually increase the duration of the active short circuit of the half-bridge arms of the bridge circuit until the bridge circuit maintains the active short circuit of the half-bridge arms.
[0013] In one embodiment, the shutdown signal interface includes a first signal interface and a second signal interface, and the step of sending a pulse shutdown signal with a gradually changing duty cycle to the shutdown signal interface in the pulse width modulation mode includes:
[0014] When the active short circuit of the half-bridge arm is the active short circuit of the upper bridge arm, a pulse shutdown signal with a gradually increasing duty cycle from the first preset duty cycle to the second preset duty cycle is sent to the first signal interface to gradually increase the duration of the active short circuit of the upper bridge arm of the bridge circuit until the bridge circuit maintains the active short circuit of the upper bridge arm.
[0015] Send a pulse shutdown signal that is continuously in the first preset duty cycle to the second signal interface.
[0016] In one embodiment, the shutdown signal interface includes a first signal interface and a second signal interface, and the step of sending a pulse shutdown signal with a gradually changing duty cycle to the shutdown signal interface in the pulse width modulation mode further includes:
[0017] When the active short circuit of the half-bridge arm is the active short circuit of the lower bridge arm, a pulse shutdown signal with a first preset duty cycle is sent to the first signal interface.
[0018] A pulse shutdown signal with a gradually increasing duty cycle from a first preset duty cycle to a second preset duty cycle is sent to the second signal interface to gradually increase the duration of the active short circuit of the upper arm of the bridge circuit until the upper arm of the bridge circuit remains actively short-circuited.
[0019] In one embodiment, when the shutdown operation type is a full shutdown, the target mode of the shutdown signal interface is a general input / output mode. The step of maintaining or adjusting the interface mode of the shutdown signal interface to the target mode and sending a shutdown signal corresponding to the shutdown operation request to the shutdown signal interface in the target mode further includes:
[0020] When the shutdown operation type corresponding to the shutdown operation request is full shutdown, the interface mode of the shutdown signal interface is maintained or adjusted to general input / output mode;
[0021] A preset high-level signal is sent to the shutdown signal interface in the general input / output mode so that the driving logic circuit controls the bridge circuit to be fully shut down.
[0022] In one embodiment, the drive logic circuit is further provided with a drive signal interface, and the control method of the electric drive system includes:
[0023] Upon receiving a shutdown operation request, the drive signals received by the drive signal interface for controlling the bridge circuit are blocked.
[0024] In one embodiment, the step of shielding the drive signal received by the drive signal interface includes:
[0025] If the type of shutdown operation corresponding to the shutdown operation request is an active short circuit of the upper bridge arm in the half-bridge arm active short circuit, the signal in the drive signal corresponding to the lower bridge arm of the bridge circuit will be shielded.
[0026] If the type of shutdown operation corresponding to the shutdown operation request is a lower bridge arm active short circuit in a half-bridge arm active short circuit, the signal in the drive signal corresponding to the upper bridge arm of the bridge circuit will be shielded.
[0027] In one embodiment, the control method for the electric drive system further includes:
[0028] If no shutdown operation request is received, the shutdown signal interface is maintained or adjusted to the general input / output mode;
[0029] A preset high-level signal is sent to the shutdown signal interface, and after a preset duration, the signal is switched to a preset low-level signal.
[0030] In addition, to achieve the above objectives, this application also proposes a vehicle, the device comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the control method for the electric drive system as described above.
[0031] In addition, to achieve the above objectives, this application also proposes a storage medium, which is a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the steps of the control method for the electric drive system as described above.
[0032] In addition, to achieve the above objectives, this application also provides a computer program product, which includes a computer program that, when executed by a processor, implements the steps of the control method for the electric drive system as described above.
[0033] One or more technical solutions proposed in this application have at least the following technical effects:
[0034] In this embodiment, the electric drive system includes a drive logic circuit and a bridge circuit. The drive logic circuit has a shutdown signal interface. Upon receiving a shutdown operation request, the target mode of the shutdown signal interface is determined based on the type of shutdown operation corresponding to the shutdown operation request. The interface mode of the shutdown signal interface is maintained or adjusted to the target mode, and a shutdown signal corresponding to the shutdown operation request is sent to the shutdown signal interface in the target mode, so that the drive logic circuit controls the shutdown of the bridge circuit based on the shutdown signal. This embodiment provides a dedicated shutdown signal interface for the shutdown signal controlling the shutdown operation, avoiding sharing the same control path with the drive signal controlling motor rotation. Simultaneously, the interface mode control dimension is added, and combined with different shutdown signals input to the shutdown signal interface, independent control of different safety shutdown operations is achieved to meet the actual needs of safety shutdown control operations. Attached Figure Description
[0035] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.
[0036] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0037] Figure 1 is a flowchart of the first embodiment of the control method of the electric drive system of this application;
[0038] Figure 2 is a flowchart of the second embodiment of the control method for the electric drive system of this application;
[0039] Figure 3 is a schematic diagram of the structure of the electric drive system in the control method of the electric drive system of this application;
[0040] Figure 4 is a flowchart of the third embodiment of the control method of the electric drive system of this application;
[0041] Figure 5 is a schematic diagram of the overall flow of the control method of the electric drive system of this application;
[0042] Figure 6 is a schematic diagram of the hardware operating environment involved in the control method of the electric drive system in the embodiments of this application.
[0043] The purpose, features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Embodiments of the present invention
[0044] It should be understood that the specific embodiments described herein are merely illustrative of the technical solutions of this application and are not intended to limit this application.
[0045] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific implementation methods.
[0046] In the field of new energy vehicles, safety shutdown (also known as safety shutdown path) is a crucial component of functional safety and the final link in the functional safety chain. After fault detection and identification of safety risks, it plays a vital role in eliminating those risks. Currently, safety shutdown paths for vehicle electric drive systems (especially the functional monitoring layer shutdown path), i.e., L2 layer shutdown paths, can be mainly divided into three types: High-side Active Short Circuit (HASC), Low-side Active Short Circuit (LASC), and complete shutdown. However, current shutdown schemes implementing these three methods primarily achieve shutdown through the control circuitry that drives the motor in the electric drive system when a fault is detected. This means that controlling motor rotation and controlling shutdown share the same control circuitry, making independent control of safety shutdown impossible and failing to meet the actual control requirements of safety shutdown.
[0047] The main solution of this application embodiment is: upon receiving a shutdown operation request, determining the target mode of the shutdown signal interface based on the type of shutdown operation corresponding to the shutdown operation request; maintaining or adjusting the interface mode of the shutdown signal interface to the target mode, and sending a shutdown signal corresponding to the shutdown operation request to the shutdown signal interface in the target mode, so that the driving logic circuit controls the shutdown of the bridge circuit based on the shutdown signal.
[0048] In this embodiment, a dedicated shutdown signal interface is provided for the shutdown signal controlling the shutdown operation, to avoid sharing the same control path with the drive signal controlling the motor rotation. Simultaneously, an interface mode control dimension is added, and by combining different shutdown signals input to the shutdown signal interface, independent control of different safety shutdown operations can be achieved, thereby meeting the actual needs of safety shutdown control operations.
[0049] The execution subject of this embodiment can be a computing service device with data processing, network communication and program execution functions, such as a controller, computer, mobile phone, etc., or a vehicle capable of performing the above functions.
[0050] Based on this, the present application provides a control method for an electric drive system. Referring to FIG1, it is a flowchart of the first embodiment of the control method for the electric drive system of the present application.
[0051] In this embodiment, the electric drive system includes a drive logic circuit and a bridge circuit. The drive logic circuit is provided with a cutoff signal interface. The control method of the electric drive system includes steps S10 to S20:
[0052] Step S10: Upon receiving a shutdown operation request, determine the target mode of the shutdown signal interface based on the type of shutdown operation corresponding to the shutdown operation request.
[0053] The aforementioned electric drive system may include a drive logic circuit and a bridge circuit. The drive logic circuit can control the closing and opening of the switches in the bridge circuit through a drive chip, thereby controlling the motor connected to the bridge circuit. Meanwhile, the main body implementing the control method of the aforementioned electric drive system may be the controller in the electric drive system. Therefore, the electric drive system may also include a controller and a drive chip.
[0054] Under normal circumstances, the controller, such as a microcontroller or DSP (Digital Signal Processor), generates control signals based on the required motor performance (such as speed, position, and torque). These signals are typically PWM (Pulse Width Modulation) signals, which determine the motor's speed and direction. The controller sends these signals to the drive logic circuit through the drive signal interface on the drive logic circuit. The drive logic circuit receives the PWM signals and other control signals from the controller. The logic circuit may include decoders, logic gates, comparators, etc., to process and convert these signals to suit the drive chip. The drive chip is the core of the drive system; it receives signals from the logic circuit and provides sufficient current and voltage to drive the power devices. The bridge circuit consists of power switching devices, such as MOSFETs or IGBTs (two different types of transistors), which switch according to the instructions of the drive chip, thereby controlling the direction and magnitude of the motor current. For DC motors, an H-bridge circuit is typically used; for AC motors, a three-phase bridge circuit is used.
[0055] For shutdown operations, embodiments of this application provide a dedicated shutdown signal interface on the driving logic circuit for receiving shutdown information signals, so as to facilitate independent shutdown control and meet the control requirements of shutdown control.
[0056] For example, the operation type corresponding to the above-mentioned shutdown operation request can be multiple, namely, active short circuit of the upper bridge, active short circuit of the lower bridge, and full shutdown. Among them, active short circuit of the upper bridge and active short circuit of the lower bridge can be referred to as active short circuit of the half-bridge arm. Accordingly, after the controller receives the shutdown operation request, it can determine the target mode of the shutdown signal interface based on the type of shutdown operation corresponding to the shutdown operation request. For example, when the shutdown operation type is active short circuit of the half-bridge arm, the target mode of the shutdown signal interface can be pulse width modulation mode, that is, PWM (Pulse Width Modulation) mode. When the shutdown operation type is full shutdown, the target mode of the shutdown signal interface can be general purpose input / output mode, that is, GPIO (General Purpose Input / Output) mode. Controlling the interface mode of the shutdown signal interface is equivalent to adding a control dimension to facilitate the differentiation of different types of shutdown operations.
[0057] Step S20: Maintain or adjust the interface mode of the shutdown signal interface to the target mode, and send a shutdown signal corresponding to the shutdown operation request to the shutdown signal interface in the target mode, so that the driving logic circuit controls the shutdown of the bridge circuit based on the shutdown signal.
[0058] For example, after determining the target mode of the shutdown signal interface, if the original interface mode of the shutdown signal interface is the target mode, then the mode of the shutdown signal interface can be maintained. Conversely, if the original interface mode of the shutdown signal interface is not the target mode, then the interface mode of the shutdown signal interface can be adjusted to the target mode. Then, a shutdown signal corresponding to the shutdown operation request can be sent to the shutdown signal interface in the target mode. If the shutdown operation request corresponds to a half-arm active short circuit, the shutdown signal sent to the shutdown signal interface can be a pulse signal. The driving logic circuit can then use the duty cycle in the pulse signal to further control the upper or lower arm of the bridge circuit to turn off. If the shutdown operation request corresponds to a full shutdown, the shutdown signal sent to the shutdown signal interface can be a high-level signal or a low-level signal, thereby causing the driving logic circuit to control the full shutdown of the bridge circuit according to the high or low level.
[0059] In this embodiment, the electric drive system includes a drive logic circuit and a bridge circuit. The drive logic circuit has a shutdown signal interface. Upon receiving a shutdown operation request, the target mode of the shutdown signal interface is determined based on the type of shutdown operation corresponding to the shutdown operation request. The interface mode of the shutdown signal interface is maintained or adjusted to the target mode, and a shutdown signal corresponding to the shutdown operation request is sent to the shutdown signal interface in the target mode, so that the drive logic circuit controls the shutdown of the bridge circuit based on the shutdown signal. This embodiment provides a dedicated shutdown signal interface for the shutdown signal controlling the shutdown operation, avoiding sharing the same control path with the drive signal controlling motor rotation. Simultaneously, the interface mode control dimension is added, and combined with different shutdown signals input to the shutdown signal interface, independent control of different safety shutdown operations is achieved to meet the actual needs of safety shutdown control operations.
[0060] Referring to Figure 2, which is a flowchart illustrating the second embodiment of the control method for the electric drive system based on the first embodiment of this application, the content that is the same as or similar to the above embodiments in this embodiment can be referred to the above description and will not be repeated hereafter. When the shutdown operation type is a half-bridge arm active short circuit, the target mode of the shutdown signal interface is a pulse width modulation mode. The step of maintaining or adjusting the interface mode of the shutdown signal interface to the target mode and sending a shutdown signal corresponding to the shutdown operation request to the shutdown signal interface in the target mode includes steps S21 to S22:
[0061] Step S21: If the type of shutdown operation corresponding to the shutdown operation request is half-bridge arm active short circuit, maintain or adjust the interface mode of the shutdown signal interface to pulse width modulation mode.
[0062] Step S22: Send a pulse shutdown signal with gradually changing duty cycle to the shutdown signal interface in the pulse width modulation mode, so that the driving logic circuit can perform soft control of the bridge circuit to actively short-circuit half-bridge arm based on the pulse shutdown signal with gradually changing duty cycle. The soft control is to gradually increase the duration of the active short circuit of the half-bridge arm of the bridge circuit until the bridge circuit maintains the active short circuit of the half-bridge arm.
[0063] Current traditional shutdown schemes directly enter a safe state upon detecting a fault. However, this leads to a problem: entering the safe state results in a large transient current due to the inherent characteristics of the circuit, especially when entering ASC (Active Short Circuit). This transient current may cause other faults, such as overcurrent faults, and in severe cases, may damage devices, thereby affecting system and personal safety. Therefore, to address the above problems, this application embodiment will implement soft control during shutdown control.
[0064] For example, when the controller in the electric drive system receives a shutdown operation request, and the shutdown operation type corresponding to the request is a half-bridge arm active short circuit, the shutdown signal interface mode is maintained or adjusted to pulse width modulation mode so that the shutdown signal interface can receive pulse signals. The half-bridge arm active short circuit type can include upper bridge arm active short circuit and lower bridge arm active short circuit. Besides half-bridge arm active short circuit, the shutdown operation type also includes full shutdown, i.e., both upper and lower bridge arms are actively short-circuited. Furthermore, if the shutdown signal interface mode is already in pulse width modulation mode, it is maintained; otherwise, it is adjusted to this mode.
[0065] After adjusting the mode of the shutdown signal interface to pulse width modulation mode, a pulse signal with a gradually changing duty cycle is sent to the shutdown signal interface. This allows the drive logic circuit to perform soft control of the bridge circuit's half-arm active short circuit based on the pulse signal with the gradually changing duty cycle. Soft control refers to gradually increasing the duration of the active short circuit of the bridge circuit's half-arm until the bridge circuit maintains the active short circuit of the half-arm. It should be noted that in practical applications, the aforementioned pulse signal with a gradually changing duty cycle can be a pulse signal with a duty cycle that increases at a certain frequency, such as gradually increasing the duty cycle from 0% to 100%, and the duration of the active short circuit of the half-arm in each control cycle is proportional to the duty cycle. Alternatively, it can be a pulse signal with a duty cycle that decreases at a certain frequency, such as gradually decreasing the duty cycle from 100% to 0%, and the duration of the active short circuit of the half-arm in each control cycle is inversely proportional to the duty cycle. In this way, the aforementioned soft control of the active short circuit of the half-arm can be achieved. It should be noted that in current conventional implementations, a safe state is directly entered upon fault detection, i.e., the bridge arm is actively short-circuited. When braking the motor is required, energy in the motor windings can be released through active short-circuiting of the bridge arm, thus achieving braking. However, since the conventional implementation directly maintains the active short circuit of the bridge arm, it is equivalent to releasing the energy in the motor windings all at once, which may lead to a large transient current, thereby damaging the device. Unlike the conventional solution, the soft control strategy in this application gradually increases the duration of the active short circuit of the half-bridge arm of the bridge circuit through pulse signals with varying duty cycles. This allows for a gradual release of energy in the motor windings, thereby avoiding the problem of excessive transient current.
[0066] In this embodiment, by using a pulse signal with varying duty cycle, the duration of the active short circuit in the half-bridge arm of the bridge circuit is gradually increased. This allows for the gradual release of energy from the motor windings, thereby preventing excessive transient current. Therefore, this embodiment can control the shutdown by sending a specific pulse signal to a designated shutdown signal interface, thus avoiding large transient currents during safe shutdown (entering a safe state) and further improving system safety performance.
[0067] In one embodiment, the shutdown signal interface includes a first signal interface and a second signal interface, and the step of sending a pulse shutdown signal with a gradually changing duty cycle to the shutdown signal interface in the pulse width modulation mode includes steps S221 to S222:
[0068] Step S221: When the active short circuit of the half-bridge arm is the active short circuit of the upper bridge arm, a pulse shutdown signal with a gradually increasing duty cycle from the first preset duty cycle to the second preset duty cycle is sent to the first signal interface to gradually increase the duration of the active short circuit of the upper bridge arm of the bridge circuit until the bridge circuit maintains the active short circuit of the upper bridge arm.
[0069] Step S222: Send a pulse shutdown signal that is continuously in the first preset duty cycle to the second signal interface.
[0070] The aforementioned shutdown signal interface may include a first signal interface and a second signal interface. Similarly, the types of active short circuits in the half-bridge arms can be divided into active short circuits in the upper bridge arm and active short circuits in the lower bridge arm. The first signal interface and the second signal interface distinguish between these two different short circuit types. The first signal interface can correspond to the upper bridge arm in the bridge circuit and is used for controlling the active short circuit of the upper bridge arm; the second signal interface can correspond to the lower bridge arm in the bridge circuit and is used for controlling the active short circuit of the lower bridge arm.
[0071] For example, when the active short circuit of the half-bridge arm is the active short circuit of the upper bridge arm, a pulse shutdown signal with a gradually increasing duty cycle from a first preset duty cycle to a second preset duty cycle is sent to the first signal interface. The duration of the active short circuit of the upper bridge arm is proportional to the duty cycle of the pulse shutdown signal received by the first signal interface. Therefore, as the duty cycle of the pulse shutdown signal received by the first signal interface gradually increases, the duration of the active short circuit of the upper bridge arm in each control cycle also gradually increases until the bridge circuit maintains the active short circuit of the upper bridge arm. Thus, the first preset duty cycle can be 0%, and the second preset duty cycle can be 100%. The lower bridge arm does not need to be actively short-circuited, so a pulse signal with a continuous first preset duty cycle is sent to the second signal interface.
[0072] In one embodiment, the shutdown signal interface includes a first signal interface and a second signal interface, and the step of sending a pulse shutdown signal with a gradually changing duty cycle to the shutdown signal interface in the pulse width modulation mode further includes steps S223 to S224:
[0073] Step S223: In the case that the active short circuit of the half-bridge arm is the active short circuit of the lower bridge arm, a pulse shutdown signal that is continuously in the first preset duty cycle is sent to the first signal interface.
[0074] Step S224: Send a pulse shutdown signal to the second signal interface, which gradually increases from a first preset duty cycle to a second preset duty cycle, so as to gradually increase the duration of the active short circuit of the upper arm of the bridge circuit until the bridge circuit maintains the active short circuit of the upper arm.
[0075] For example, when the active short circuit of the half-bridge arm is the active short circuit of the lower bridge arm, a pulse shutdown signal with a gradually increasing duty cycle from a first preset duty cycle to a second preset duty cycle is sent to the second signal interface. The duration of the active short circuit of the lower bridge arm is proportional to the duty cycle of the pulse shutdown signal received by the second signal interface. Therefore, as the duty cycle of the pulse shutdown signal received by the second signal interface gradually increases, the duration of the active short circuit of the lower bridge arm in each control cycle also gradually increases until the bridge circuit maintains the active short circuit of the lower bridge arm. Correspondingly, the first preset duty cycle can be 0%, and the second preset duty cycle can be 100%. The upper bridge arm does not need to be actively short-circuited, so a pulse signal with a continuous first preset duty cycle is sent to the first signal interface.
[0076] In this embodiment of the application, the upper arm or lower arm of the bridge circuit can be actively short-circuited by sending pulse turn-off signals with different duty cycles to the first signal interface and the second signal interface.
[0077] In one embodiment, the drive logic circuit is further provided with a drive signal interface, and the control method of the electric drive system includes:
[0078] Step S30: Upon receiving a shutdown operation request, the drive signal received by the drive signal interface for controlling the bridge circuit is blocked.
[0079] The drive logic circuit is also equipped with a drive signal interface, which is used to receive drive signals (usually PWM signals) for normal motor control when no safety shutdown operation is performed. For example, the drive signal can control the magnitude and direction of the current in the motor through the switch in the control bridge circuit, thereby controlling the speed and direction of the motor.
[0080] For example, in the case of receiving a shutdown operation request, in order to avoid the drive signal received by the drive signal interface for controlling the bridge circuit conflicting with the shutdown signal received by the shutdown signal interface, or affecting the execution of the shutdown operation request, the drive signal received by the drive signal interface will be blocked in this embodiment. That is, the shutdown operation request will be executed by the drive logic circuit with priority over the drive signal.
[0081] In one embodiment, the step of shielding the drive signal received by the drive signal interface includes steps S31 to S32:
[0082] Step S31: If the type of shutdown operation corresponding to the shutdown operation request is active short circuit of the upper bridge arm in the half-bridge arm active short circuit, the signal in the drive signal corresponding to the lower bridge arm of the bridge circuit is shielded.
[0083] Step S32: If the type of shutdown operation corresponding to the shutdown operation request is a lower bridge arm active short circuit in a half-bridge arm active short circuit, the signal in the drive signal corresponding to the upper bridge arm of the bridge circuit is shielded.
[0084] For example, when the shutdown operation request corresponds to a shutdown operation of type 1, which is an active short circuit of the upper bridge arm in a half-bridge arm active short circuit, the signal in the drive signal corresponding to the lower bridge arm of the bridge circuit is masked. If the drive logic circuit controls the bridge circuit through the drive chip, the enable signal corresponding to the lower bridge drive chip in the drive chip can be set to disabled, thus masking the lower bridge drive chip (while the upper bridge arm mainly responds to the signal received by the first signal interface). Conversely, when the shutdown operation request corresponds to a shutdown operation of type 2, which is an active short circuit of the lower bridge arm in a half-bridge arm active short circuit, the signal in the drive signal corresponding to the upper bridge arm of the bridge circuit is masked. If the drive logic circuit controls the bridge circuit through the drive chip, the enable signal corresponding to the upper bridge drive chip in the drive chip can be set to disabled, thus masking the upper bridge drive chip.
[0085] Referring to Figure 3, which is a schematic diagram of the electric drive system in an embodiment of this application, the drive logic circuit controls the bridge circuit through the drive chip. For example, if six switches are provided in the bridge circuit, the original six PWM drive signals (i.e., the signals received by the drive signals) in the figure each control the closing and opening of one switch. IO-H and IO-L in the figure are the first and second signal interfaces mentioned above, respectively. When IO-H and IO-L receive a shutdown signal (such as a pulse signal with a gradually changing duty cycle in pulse width modulation mode, or a preset high-level signal in general purpose input / output mode), the drive logic circuit can control the drive logic circuit to shield all or part of the original six PWM drive signals. The drive logic circuit then generates new PWM drive signals based on the shutdown signals received by IO-H and IO-L, i.e., the processed six PWM drive signals, and sends them to the drive chip to control the bridge circuit.
[0086] Referring to Figure 4, which is a flowchart illustrating the first and second embodiments of the control method for the electric drive system based on this application, and the proposed third embodiment, the same or similar content as the above embodiments can be referred to the above description and will not be repeated hereafter. When the shutdown operation type is full shutdown, the target mode of the shutdown signal interface is a general input / output mode. The step of maintaining or adjusting the interface mode of the shutdown signal interface to the target mode, and sending a shutdown signal corresponding to the shutdown operation request to the shutdown signal interface in the target mode, further includes steps A21 to A22:
[0087] Step A21: If the type of shutdown operation corresponding to the shutdown operation request is full shutdown, maintain or adjust the interface mode of the shutdown signal interface to general input / output mode.
[0088] Step A22: Send a preset high-level signal to the shutdown signal interface in the general input / output mode so that the driving logic circuit controls the bridge circuit to be fully shut down.
[0089] For example, when a shutdown operation request is received, and the type of shutdown operation corresponding to the request is full shutdown, the mode of the shutdown signal interface is maintained or adjusted to general input / output mode. Full shutdown means turning off all switching devices (such as IGBTs or MOSFETs) in the bridge circuit. If the shutdown signal interface is already in general input / output mode, then that mode is maintained; otherwise, if it is not in general input / output mode, it needs to be adjusted to that mode. By setting the mode of the shutdown signal interface, different types of shutdown operations corresponding to the shutdown operation request can be distinguished. When the type of shutdown operation corresponding to the shutdown operation request is full shutdown, a preset high-level signal can be sent to the shutdown signal interface in general input / output mode. The drive logic circuit receiving the preset high-level signal can then perform a full shutdown operation on the bridge circuit.
[0090] In one embodiment, the control method of the electric drive system further includes steps B10 to B20:
[0091] Step B10: If no shutdown operation request is received, maintain or adjust the mode of the shutdown signal interface to general input / output mode;
[0092] Step B20: Send a preset high-level signal to the shutdown signal interface, and after a preset duration, switch to sending a preset low-level signal to the shutdown signal interface.
[0093] For example, when no shutdown operation request is received under normal circumstances, the shutdown signal interface is maintained or adjusted to the general input / output mode. That is, under normal conditions, the shutdown signal interface is in general input / output mode. A preset low-level signal is sent to the shutdown signal interface to indicate that no shutdown operation request exists and no shutdown operation is required; the interface is normally controlled based on the signal received from the drive signal interface. It is worth noting that, when no shutdown operation request is received, a preset high-level signal can be sent to the shutdown signal interface first and maintained for a preset duration. This involves performing a full shutdown operation to initialize the state of each switch in the bridge circuit, reducing safety risks to the electric drive system. After maintaining the preset duration, the system switches back to sending a preset low-level signal to the shutdown signal interface to indicate that no shutdown operation request exists. The voltage of the preset low-level signal is lower than that of the preset high-level signal. The specific voltage values of the high and low level signals can be set by those skilled in the art and will not be elaborated here.
[0094] Referring to Figure 5, which is a schematic diagram of the overall process of an embodiment of this application, as shown in the figure, three safety states are set in this embodiment: active short circuit of the upper bridge, active short circuit of the lower bridge, and full shutdown (i.e., full shutdown); two hardware I / O ports are set up, namely IO-H and IO-L (i.e., the first signal interface and the second signal interface mentioned above, respectively), and are initialized to GPIO (General Purpose Input / Output) mode, with all levels set to low, such as 0; different safety states are controlled by controlling different combinations of signals received by IO-H and IO-L, wherein:
[0095] ① When both IO-H and IO-L are low, no safety shutdown is performed; ② When IO-H is high and IO-L is low, the upper bridge is actively short-circuited; ③ When IO-H is low and IO-L is high, the lower bridge is actively short-circuited; ④ When both IO-H and IO-L are high, a full shutdown is achieved; When a full shutdown is requested, the attributes of IO-H and IO-L are set to GPIO mode, and both IO-H and IO-L are set to high-level output.
[0096] When requesting ASC for the upper bridge, set the attributes of IO-H and IO-L to PWM (Pulse Width Modulation) mode, and set the output duty cycle and frequency of IO-H and IO-L respectively. Specifically, set the IO-H duty cycle to start at 0% and gradually increase in steps of Step-ASC (i.e., the control cycle, which can be set by the technician according to requirements), with a maximum value of 100%, and set the frequency to Frq-ASC; simultaneously, set the IO-H duty cycle to 0%, the frequency to Frq-ASC, and disable the corresponding enable signal for the lower bridge driver chip, thus disabling the lower bridge driver chip. When requesting ASC for the lower bridge, set the attributes of IO-H and IO-L to PWM mode, and set the output duty cycle and frequency of IO-H and IO-L respectively. The IO-L duty cycle is set to start from 0% and gradually increase in steps Step-ASC, with a maximum value of 100%, and the frequency is set to Frq-ASC. Simultaneously, the IO-L duty cycle is set to 0%, the frequency is set to Frq-ASC, and the enable signal for the upper bridge driver chip is disabled, thus disabling the upper bridge driver chip. When the functional monitoring layer does not request any safety shutdown, to ensure reliable and safe execution of the full shutdown state under safe state switching conditions, the attributes of IO-H and IO-L are first set to normal GPIO mode. Then, the output levels of IO-H and IO-L are both set to high level (for initialization), and a delay time T-Delay is set. Finally, the output levels of IO-H and IO-L are both set to low level.
[0097] This application provides a vehicle, the vehicle including: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform the control method of the electric drive system in the above embodiment 1.
[0098] Referring to Figure 6 below, a structural schematic diagram suitable for implementing the vehicle embodiments of this application is shown. The vehicle in the embodiments of this application may be configured with mobile terminals such as computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Description), PMPs (Portable Media Players), in-vehicle terminals (e.g., in-vehicle navigation terminals), and fixed terminals such as computers. The vehicle shown in Figure 6 is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of this application.
[0099] As shown in Figure 6, the vehicle may include a processing unit 1001 (e.g., a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 1002 or a program loaded from a storage device 1003 into a random access memory (RAM) 1004. The RAM 1004 also stores various programs and data required for vehicle operation. The processing unit 1001, ROM 1002, and RAM 1004 are interconnected via a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Typically, the following systems can be connected to the I / O interface 1006: input devices 1007 including, for example, a touchscreen, touchpad, keyboard, mouse, image sensor, microphone, accelerometer, gyroscope, etc.; output devices 1008 including, for example, a liquid crystal display (LCD), speaker, vibrator, etc.; storage devices 1003 including, for example, magnetic tape, hard disk, etc.; and communication devices 1009. The communication device 1009 allows the vehicle to communicate wirelessly or wiredly with other devices to exchange data. Although vehicles with various systems are shown in the figures, it should be understood that implementation or possession of all the systems shown is not required. More or fewer systems may be implemented alternatively.
[0100] According to the embodiments disclosed in this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments disclosed in this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code 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 device, or installed from storage device 1003, or installed from ROM 1002. When the computer program is executed by processing device 1001, it performs the functions defined in the methods of the embodiments disclosed in this application.
[0101] The vehicle provided in this application, employing the control method of the electric drive system in the above embodiments, can solve the technical problem of the inability to independently control the safety shutdown. Compared with the prior art, the beneficial effects of the vehicle provided in this application are the same as those of the control method of the electric drive system provided in the above embodiments, and other technical features of the vehicle are the same as those disclosed in the method of the previous embodiment, and will not be repeated here.
[0102] It should be understood that the various parts disclosed in this application can be implemented using hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples.
[0103] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.
[0104] This application provides a computer-readable storage medium having computer-readable program instructions (i.e., a computer program) stored thereon, the computer-readable program instructions being used to execute the control method of the electric drive system in the above embodiments.
[0105] The computer-readable storage medium provided in this application may be, for example, a USB flash drive, but is not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to: electrical connections having one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, system, or device. The program code contained on the computer-readable storage medium may be transmitted using any suitable medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination thereof.
[0106] The aforementioned computer-readable storage medium may be included in the vehicle or may exist independently and not installed in the vehicle.
[0107] The aforementioned computer-readable storage medium carries one or more programs that, when executed by a vehicle, cause the vehicle to:
[0108] Upon receiving a shutdown operation request, the target mode of the shutdown signal interface is determined based on the type of shutdown operation corresponding to the shutdown operation request.
[0109] Maintain or adjust the interface mode of the shutdown signal interface to the target mode, and send a shutdown signal corresponding to the shutdown operation request to the shutdown signal interface in the target mode, so that the driving logic circuit controls the shutdown of the bridge circuit based on the shutdown signal.
[0110] Computer program code for performing the operations of this application can be written in one or more programming languages or a combination thereof, including object-oriented programming languages such as Java, Smalltalk, and C++, and conventional procedural programming languages such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a Local Area Network (LAN) or a Wide Area Network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).
[0111] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a 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 the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, 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.
[0112] The modules described in the embodiments of this application can be implemented in software or hardware. The names of the modules do not necessarily limit the functionality of the unit itself.
[0113] The readable storage medium provided in this application is a computer-readable storage medium that stores computer-readable program instructions (i.e., a computer program) for executing the control method of the above-described electric drive system, thereby solving the technical problem of the inability to independently control the safety shutdown. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided in this application are the same as the beneficial effects of the control method of the electric drive system provided in the above embodiments, and will not be repeated here.
[0114] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the control method for the electric drive system as described above.
[0115] The computer program product provided in this application can solve the technical problem of controlling electric drive systems. Compared with the prior art, the beneficial effects of the computer program product provided in this application are the same as the beneficial effects of the electric drive system control method provided in the above embodiments, and will not be repeated here.
[0116] The above description is only a part of the embodiments of this application and does not limit the patent scope of this application. All equivalent structural transformations made under the technical concept of this application and using the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included in the patent protection scope of this application.
Claims
1. A control method for an electric drive system, wherein, The electric drive system includes a drive logic circuit and a bridge circuit. The drive logic circuit is provided with a disconnect signal interface. The control method of the electric drive system includes: Upon receiving a shutdown operation request, the target mode of the shutdown signal interface is determined based on the type of shutdown operation corresponding to the shutdown operation request. Maintain or adjust the interface mode of the shutdown signal interface to the target mode, and send a shutdown signal corresponding to the shutdown operation request to the shutdown signal interface in the target mode, so that the driving logic circuit controls the shutdown of the bridge circuit based on the shutdown signal.
2. The control method for the electric drive system as described in claim 1, wherein, When the shutdown operation type is a half-bridge arm active short circuit, the target mode of the shutdown signal interface is a pulse width modulation mode. The step of maintaining or adjusting the interface mode of the shutdown signal interface to the target mode and sending a shutdown signal corresponding to the shutdown operation request to the shutdown signal interface in the target mode includes: When the type of shutdown operation corresponding to the shutdown operation request is half-bridge arm active short circuit, the interface mode of the shutdown signal interface is maintained or adjusted to pulse width modulation mode. A pulse shutdown signal with a gradually changing duty cycle is sent to the shutdown signal interface in the pulse width modulation mode, so that the driving logic circuit performs soft control of the bridge circuit to actively short-circuit half-bridge arms based on the pulse shutdown signal with the gradually changing duty cycle. The soft control is to gradually increase the duration of the active short circuit of the half-bridge arms of the bridge circuit until the bridge circuit maintains the active short circuit of the half-bridge arms.
3. The control method for the electric drive system as described in claim 2, wherein, The shutdown signal interface includes a first signal interface and a second signal interface. The step of sending a pulse shutdown signal with a gradually changing duty cycle to the shutdown signal interface in the pulse width modulation mode includes: When the active short circuit of the half-bridge arm is the active short circuit of the upper bridge arm, a pulse shutdown signal with a gradually increasing duty cycle from the first preset duty cycle to the second preset duty cycle is sent to the first signal interface to gradually increase the duration of the active short circuit of the upper bridge arm of the bridge circuit until the bridge circuit maintains the active short circuit of the upper bridge arm. Send a pulse shutdown signal that is continuously in the first preset duty cycle to the second signal interface.
4. The control method for the electric drive system as described in claim 2 or 3, wherein, The shutdown signal interface includes a first signal interface and a second signal interface. The step of sending a pulse shutdown signal with a gradually changing duty cycle to the shutdown signal interface in the pulse width modulation mode further includes: When the active short circuit of the half-bridge arm is the active short circuit of the lower bridge arm, a pulse shutdown signal with a first preset duty cycle is sent to the first signal interface. A pulse shutdown signal with a gradually increasing duty cycle from a first preset duty cycle to a second preset duty cycle is sent to the second signal interface to gradually increase the duration of the active short circuit of the upper arm of the bridge circuit until the upper arm of the bridge circuit remains actively short-circuited.
5. The control method for the electric drive system as described in any one of claims 1 to 4, wherein, When the shutdown operation type is full shutdown, the target mode of the shutdown signal interface is general input / output mode. The step of maintaining or adjusting the interface mode of the shutdown signal interface to the target mode and sending a shutdown signal corresponding to the shutdown operation request to the shutdown signal interface in the target mode further includes: When the shutdown operation type corresponding to the shutdown operation request is full shutdown, the interface mode of the shutdown signal interface is maintained or adjusted to general input / output mode; A preset high-level signal is sent to the shutdown signal interface in the general input / output mode so that the driving logic circuit controls the bridge circuit to be fully shut down.
6. The control method for the electric drive system as described in any one of claims 1 to 5, wherein, The drive logic circuit is also provided with a drive signal interface, and the control method of the electric drive system includes: Upon receiving a shutdown operation request, the drive signals received by the drive signal interface that are configured to control the bridge circuit are blocked.
7. The control method for the electric drive system as described in claim 6, wherein, The step of shielding the drive signal received by the drive signal interface includes: If the type of shutdown operation corresponding to the shutdown operation request is an active short circuit of the upper bridge arm in the half-bridge arm active short circuit, the signal in the drive signal corresponding to the lower bridge arm of the bridge circuit will be shielded. If the type of shutdown operation corresponding to the shutdown operation request is a lower bridge arm active short circuit in a half-bridge arm active short circuit, the signal in the drive signal corresponding to the upper bridge arm of the bridge circuit will be shielded.
8. The control method for the electric drive system as described in any one of claims 1 to 7, wherein, The control method for the electric drive system further includes: If no shutdown operation request is received, the shutdown signal interface is maintained or adjusted to the general input / output mode; A preset high-level signal is sent to the shutdown signal interface, and after a preset duration, the signal is switched to a preset low-level signal.
9. A vehicle, wherein, The vehicle includes: a processor, a memory, and a control program for an electric drive system stored in the memory and executable on the processor, wherein the control program for the electric drive system, when executed, implements the steps of the control method for the electric drive system as described in any one of claims 1 to 8.
10. A computer-readable storage medium, wherein, The computer-readable storage medium stores a control program for an electric drive system, which, when executed, implements the steps of the control method for the electric drive system as described in any one of claims 1 to 8.