A control method for intelligent power replenishment in hybrid electric vehicles

Abstract

This invention discloses a control method for intelligent battery replenishment in hybrid electric vehicles, comprising the following steps: when the passenger powers off and locks the vehicle; sensors transmit the battery's State of Charge (SOC) signal; it is determined whether the battery's SOC is at the lower limit threshold for replenishment; if so, the IBS wakes up the CEM (Center for Activated Battery Management), the CEM identifies and determines whether the master node is woken up due to the SOC lower limit threshold, and wakes up the CAN network; the CAN network monitors the battery's SOC value and the battery level, and controls the start and stop of replenishment. During the power-off process, this invention, based on the detected battery status, transmits the battery status signal to the main control unit (VCU) via LIN (Linear Induction Unit), thereby enabling the VCU to confirm the replenishment status and resolving the potential for vehicle battery depletion caused by frequent wake-up replenishment.

Description

Technical Field

[0001] This invention relates to the field of automotive battery charging technology, specifically a control method for intelligent charging of hybrid electric vehicles. Background Technology

[0002] Currently, the intelligent charging function used in a certain hybrid electric vehicle involves the following steps: During the power-off process after locking the vehicle, any frame message on the new energy vehicle's CAN bus will wake up the VCU. The VCU periodically wakes up to detect the voltage of the 12V battery to determine if charging is needed. The setting of the charging duration and the current loss from frequent waking for charging both contribute to battery drain. By calculating the battery's status based on the detected charging / discharging current, voltage, and terminal temperature, and transmitting the battery status signal to the main control unit via LIN, the VCU can confirm the charging status, thus mitigating the potential battery depletion caused by frequent waking for charging. Summary of the Invention

[0003] Technical problems to be solved

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a control method for intelligent power replenishment in hybrid electric vehicles.

[0005] Technical Solution

[0006] To achieve the above objectives, the present invention provides the following technical solution: a control method for intelligent power replenishment of a hybrid electric vehicle, comprising the following steps: after the passenger turns off the power and locks the vehicle;

[0007] The sensor transmits the battery's state of charge (SOC) signal;

[0008] Determine whether the battery's state of charge (SOC) is at the lower limit threshold for charging when additional charging is needed.

[0009] If so, IBS wakes up CEM, CEM identifies and determines whether the master node is woken up due to the SOC power limit threshold, and then wakes up the CAN network;

[0010] The CAN network monitors the battery's SOC value and the small battery's charge level, and controls the start and stop of recharging.

[0011] The battery status is calculated by monitoring the battery charging and discharging current, voltage, and terminal temperature using sensors.

[0012] As mentioned above, the battery SOC signal is sent from IBS to VCU via LIN, and VCU determines whether to start the high-voltage DC-DC converter to charge the battery.

[0013] The aforementioned system also includes a monitoring unit. A 0x37 frame is added to the wake-up message signal from the slave node. The corresponding signal thresholds can be configured offline. When the IBS sends a low-level signal to wake up the master controller, master-slave LIN communication begins. This is to prevent the VCU from being frequently woken up due to arbitrary frame error messages, which could damage the vehicle.

[0014] The specific method by which CEM identifies and determines whether the master node is woken up due to the lower limit threshold of SOC power is as follows: CEM identifies and determines whether the value of SOCWU is 0x1. When wake-up is required, IBS sends SOCWU as 0x1 for 10 minutes, and then changes it to 0x0 after 10 minutes.

[0015] As mentioned above, when the CAN network performs intelligent power replenishment, it does not consider the SOCWU value, but only monitors the SOC value. Power replenishment stops when the battery's charge level exceeds a certain value or the charging current falls below a certain value. When the BMS's SOC is less than 20%, the vehicle stops power replenishment to avoid battery depletion; when SOC is greater than or equal to 20%, SOCWU is set to 0x1, indicating that power replenishment can continue. At this time, the CDU starts, and the high voltage on the DC-DC converter replenishes the battery.

[0016] The specific logic for IBS to wake up CEM is as follows: IBS detects the following three signals: SOC < SOCWkUpThrd; abs (Discharge current) >

[0017] DischargeCurrentWkUpThrd for 64 seconds; abs(Charge current) > ChargingCurrentWkUpThrd for 64 seconds. If one of these conditions is met and Lin is off, IBS will send a standard wake-up signal to the Lin bus.

[0018] As mentioned above, IBS sends a standard wake-up signal to the Lin bus, with a low-level duration of 250µs to 5ms. The first wake-up signal is sent 30 minutes after Lin turns off. It sends three low-level signals at a time, with an interval of 150ms to 250ms. If it fails to wake up on the first attempt, the next low-level signal will be sent at an interval of 240 minutes, and the next one will also be sent at an interval of 240 minutes.

[0019] A computer-readable storage medium having a computer program stored thereon, which is executed by a processor to implement the above-described intelligent power replenishment control method for a hybrid electric vehicle.

[0020] Beneficial effects:

[0021] Compared with existing technologies, this intelligent power replenishment control method for hybrid electric vehicles has the following advantages:

[0022] This invention, during the intelligent battery replenishment function's operation while the vehicle is locked and powered off, transmits the battery status signal to the main control unit (VCU) via LIN based on the detected battery status. This allows the VCU to confirm the replenishment status, resolving the potential for vehicle battery depletion caused by frequent wake-up replenishment. It effectively sets a threshold range for battery replenishment, stopping replenishment once the target threshold is reached, avoiding continued replenishment even after the target value is achieved. This intelligent battery replenishment strategy (IBS) for hybrid electric vehicles, controlled by the VCU, can address similar issues in other new energy projects.

[0023] Other advantages, objectives and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination or study, or may be learned from the practice of the invention. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the VCU control strategy of the present invention;

[0025] Figure 2 This is a schematic diagram of the wake-up function signal interval of the present invention. Figure 1 ;

[0026] Figure 3 This is a schematic diagram of the wake-up function signal interval of the present invention. Figure 2 . Detailed Implementation

[0027] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0028] like Figure 1-3 As shown, the present invention provides a technical solution: Referring to Figure 1 As shown, the steps include: after the passenger turns off the power to lock the car;

[0029] The sensors transmit the battery's State of Charge (SOC) signal; the battery status is calculated by monitoring the battery's charging and discharging current, voltage, and terminal temperature. The SOC signal is sent from the IBS to the VCU via LIN, and the VCU determines whether to apply a high-voltage DC-DC converter to recharge the battery. A monitoring unit is also included to prevent the VCU from frequently waking up due to arbitrary frame error messages, which could damage the vehicle.

[0030] Determine whether the battery's state of charge (SOC) is at the lower limit threshold for charging when additional charging is needed.

[0031] If so, IBS wakes up CEM. CEM identifies and determines whether the master node is being woken up due to the SOC power threshold, and then wakes up the CAN network. The specific logic for IBS waking up CEM is as follows: IBS detects the following three signals: SOC < SOCWkUpThrd; abs (Discharge current) > DischargeCurrentWkUpThrd for 64 seconds; abs (Chargecurrent) > ChargingCurrentWkUpThrd for 64 seconds. If any one of these conditions is met and Lin is off, IBS will send a standard wake-up signal to the Lin bus. IBS sends a standard wake-up signal to the Lin bus with a low-level duration of 250µs to 5ms. The first wake-up signal is sent 30 minutes after Lin is off, and three low-level signals are sent at a time, with intervals of 150ms to 250ms. If the first wake-up fails, the next low-level signal interval is 240 minutes, and the interval after that is also 240 minutes.

[0032] The specific method by which CEM identifies and determines whether the master node is woken up due to the SOC power threshold is as follows:

[0033] CEM identifies and determines whether the value of SOCWU is 0x1. When wake-up is required, IBS sends SOCWU as 0x1 for 10 minutes, after which it changes to 0x0.

[0034] The CAN network monitors the battery's State of Charge (SOC) and the small battery's charge level, controlling the start and stop of charging. During subsequent intelligent charging, the CAN network disregards the SOCWU value, only monitoring the SOC. Charging stops when the small battery's charge level exceeds a certain value or the charging current falls below a certain value. When the BMS's SOC is less than 20%, charging stops to prevent battery depletion; when SOC is ≥ 20%, SOCWU is set to 0x1, indicating that charging can continue. At this point, the CDU activates, and the high voltage on the DC-DC converter charges the battery.

[0035] It should be noted that in this document, the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used solely for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. The terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, unless otherwise explicitly specified and limited, the terms "fixed," "installed," "connected," and "linked" should be interpreted broadly. For example, "installed" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a mechanical connection or an electrical connection; "linked" can be a direct connection, an indirect connection through an intermediate medium, or a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0036] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A control method for intelligent power replenishment in a hybrid electric vehicle, characterized in that: This includes the following steps: after the passenger turns off the electric lock; The sensor transmits the battery's state of charge (SOC) signal; Determine whether the battery's state of charge (SOC) is at the lower limit threshold for charging when additional charging is needed. If so, IBS wakes up CEM, CEM identifies and determines whether the master node is woken up due to the SOC power limit threshold, and then wakes up the CAN network; The CAN network monitors the battery's SOC value and the small battery's power, and controls the start and stop of charging. A monitoring unit is also set up. The wake-up message signal from the slave node is increased by a 0x37 frame. The corresponding signal threshold can also be set through offline configuration. When the IBS sends a low-level signal to wake up the master controller, the master and slave start LIN communication. This is to prevent the VCU from being woken up frequently due to arbitrary frame error messages, which could cause vehicle damage. The specific method by which CEM identifies and determines whether the master node is woken up due to the lower limit threshold of SOC power is as follows: CEM identifies and determines whether the value of SOCWU is 0x1. When wake-up is required, IBS sends SOCWU as 0x1 for 10 minutes, and then changes it to 0x0 after 10 minutes. When the CAN network performs intelligent power replenishment, it does not consider the SOCWU value, but only monitors the SOC value. Power replenishment is stopped when the small battery's charge level exceeds a certain value or the charging current falls below a certain value. When the SOC of the BMS is less than 20%, the vehicle stops charging to avoid power depletion; when the SOC is greater than or equal to 20%, the SOCWU is set to 0x1, indicating that charging can continue. At this time, the CDU starts and the high voltage on the DC-DC converter charges the battery. The specific logic for IBS to wake up CEM is as follows: IBS detects the following three signals: SOC < SOCWkUpThrd; abs (Discharge current) > DischargeCurrentWkUpThrd for 64 seconds; abs (Charge current) > ChargingCurrentWkUpThrd for 64 seconds. If any one of these conditions is met and Lin is off, IBS will send a standard wake-up signal to the Lin bus.

2. The intelligent power replenishment control method for a hybrid electric vehicle according to claim 1, characterized in that: The battery status is determined by monitoring the battery's charging and discharging current, voltage, and terminal temperature using sensors.

3. The control method for intelligent power replenishment of a hybrid electric vehicle according to claim 2, characterized in that: The battery SOC signal is sent from IBS to VCU via LIN. VCU then determines whether to apply a high-voltage DC-DC converter to the starting high-voltage DC-DC converter to charge the battery.

4. The intelligent power replenishment control method for a hybrid electric vehicle according to claim 1, characterized in that: IBS sends a standard wake-up signal to the Lin bus. The low-level duration is 250µs to 5ms. The first wake-up signal is sent 30 minutes after Lin is off. It sends three low-level signals at a time, with an interval of 150ms to 250ms. If it fails to wake up on the first attempt, the next low-level signal will be sent at an interval of 240 minutes, and the next one will also be sent at an interval of 240 minutes.

5. A computer-readable storage medium having a computer program stored thereon, characterized in that, The program is executed by the processor to implement a control method for intelligent power replenishment of a hybrid electric vehicle as described in any one of claims 1-4.

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