[0034] In order to enable those skilled in the art to better understand the solutions of the embodiments of the present invention, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.
[0035] In view of the current acquisition of the power-off time of new energy vehicles, only the TBOX is used for monitoring, and it is prone to the problem that the power-off time may be inaccurately obtained when the TBOX fails or fails. The invention provides a method and system for calculating the power-off time of a new energy vehicle. By setting the TBOX time valid flag bit, the accumulated TBOX power-on time is obtained when the time valid flag bit is 1, and the total power-on time is obtained when the time valid flag bit is 0. The vehicle controller counts the accumulated failure time, and then calculates the power-off time of the entire vehicle. It solves the problem that the power-off time of new energy vehicles is mainly monitored and obtained through the on-board terminal TBOX, which is prone to inaccurate acquisition of the power-off time when the TBOX fails, which can improve the safety of the battery management system and the accuracy of battery state estimation.
[0036] like figure 1 As shown, a method for calculating the power-off time of a new energy vehicle includes:
[0037] S1: Set the time valid flag bit of the TBOX. When the TBOX is in a normal working state, the time valid flag bit is 1, and when the TBOX is in an invalid state, the time valid flag bit is 0.
[0038] S2: Obtain the initial power-on time of the TBOX, and obtain the accumulated power-on time before the TBOX becomes invalid when the time valid flag bit changes from 1 to 0.
[0039] S3: When the time valid flag bit is 0, turn on the vehicle controller to count the accumulated invalid time.
[0040] S4: Calculate and obtain the absolute time according to the cumulative power-on time before the failure and the cumulative time of failure.
[0041] S5: Acquire the battery working state of the power battery, and calculate and obtain the power-off time of the battery according to the battery working state and the absolute time.
[0042] Specifically, by setting the time valid flag bit on the TBOX, when the time valid flag bit is 1, the accumulated power-on time is obtained through the TBOX, and when the time valid flag bit is 0, the MCU in the vehicle controller performs timing to obtain the cumulative failure accumulation time. The power-on time, and then the power-off time of the whole vehicle can be obtained, so that the accurate power-off time of the vehicle can still be calculated in the TBOX failure stage, and the influence of the functional stability of the TBOX electronic components on the accurate calculation of the power-off time can be reduced. At the same time, this strategy method can realize the calibration of the power-off time data obtained by the TBOX, further improve the accuracy of the vehicle power-off time, and ensure the effective realization of the battery management function of new energy vehicles.
[0043] Further, the method also includes:
[0044] S6: When the time valid flag bit is 1, obtain the valid cumulative time of power-on of the TBOX.
[0045] S7: Use the difference between the effective power-on accumulation time and the power-on initial time as the absolute time.
[0046] In practical applications, after the vehicle is powered on, set the corresponding time valid flag bit as xxxflag (such as invalid_flag, server_flag, GPS_flag, estimated_flag) according to the TBOX time source, and obtain the initial time of TBOX power-on. Use xxxflag and Tbox time validity (validity of year, month, day, etc.) as the test parameters to check whether the TBOX is invalid, and output the TBOX validity flag bit tbox_vaild_flag, the flag bit is 0 means that the TBOX is in the invalid state, the vehicle controller VCU After receiving the TBOX failure status flag bit 0, set the mcu_vaild_flag flag bit to 1 to enable the MCU timing function, so that the cumulative power-on time from the TBOX failure to the current power-on time is recorded as the failure cumulative power-on time; if the output TBOX validity The flag bit tbox_vaild_flag is 1, that is, it is determined that the TBOX is working normally. After the VCU receives the TBOX failure status flag bit 1, it sends the mcu_vaild_flag flag bit of 0 to stop the MCU timing function.
[0047]The absolute time calculated according to the cumulative power-on time before the failure and the cumulative failure time includes: if the TBOX fails and recovers during this power-on process, the absolute time is equal to the cumulative power-on time before the failure. The sum of time and the cumulative time to failure.
[0048] The calculating and obtaining the absolute time according to the cumulative power-on time before the failure and the cumulative failure time, further comprising: if the TBOX fails during this power-on process and does not recover, obtaining the power-off time of the entire vehicle, and calculating The difference between the cumulative failure time and the power-off time of the entire vehicle, and the absolute time is equal to the sum of the cumulative power-on time before failure and the difference.
[0049] In practical applications, if the TBOX fails and recovers during the power-on process: record the initial power-on time T0 of the TBOX, the cumulative power-on time t1 before the TBOX fails, and enable the MCU timing function to record the cumulative MCU time △t after the TBOX fails. When the current time T2 is recorded after the TBOX resumes work, T0+t1+△t and T2 can be calibrated with each other. If the deviation is large, t1+△t is used as the cumulative power-on time before the Tbox resumes, and t2 is recorded as the time after the TBOX returns to normal. To the power-on time of this power-off, T=(t1+△t)+t2.
[0050] If the TBOX fails during the current power-on process, it will be restored in the next power-on process: record the initial time T0 of the current power-on, the accumulated power-on time t1 before the TBOX fails, and enable the MCU timely function after the Tbox fails to record the accumulated time of the MCU △ t, then the cumulative power-on time in this power-on process is t1+△t. Continue to turn on the MCU accumulated time △t2 after the next power-on. When the TBOX recovers after the next power-on, record the current time T2, and record the accumulated power-on time after the TBOX is restored as t2, then the accumulated power-on time of the next power-on is △ t2+t2. The total power-on time of two power-ups is T=(t1+△t)+(△t2+t2).
[0051] If the TBOX fails during the current power-on process and does not recover in the next power-on process: record the initial time T0 of this power-on, the accumulated power-on time t1 before the TBOX fails, and enable the MCU timely function after the TBOX fails to record the cumulative power-on time of the MCU Time △t1, the cumulative power-on time during this power-on process is t1+△t. After the next power-on, the MCU will continue to turn on the accumulated time △t2 until the power is turned off. By analogy, the accumulated time of the third power-on is △t3, and the accumulated time of the nth power-on is △tn. Then the cumulative power-on time before TBOX is restored is T=t1+△t1+△t2+△t3+…+△tn.
[0052] It can be seen that the present invention provides a method for calculating the power-off time of a new energy vehicle. By setting the TBOX time valid flag bit, the accumulated power-on time of the TBOX is obtained when the time valid flag bit is 1, and the total power-on time is obtained when the time valid flag bit is 0. The vehicle controller counts the accumulated failure time, and then calculates the power-off time of the entire vehicle. It solves the problem that the power-off time of new energy vehicles is mainly monitored and obtained through the on-board terminal TBOX, which is prone to inaccurate acquisition of the power-off time when the TBOX fails, which can improve the safety of the battery management system and the accuracy of battery state estimation.
[0053] The present invention also provides a system for calculating the power-off time of a new energy vehicle, comprising:
[0054] The setting unit is used to set the time valid flag bit of the TBOX. When the TBOX is in a normal working state, the time valid flag bit is 1, and when the TBOX is in an invalid state, the time valid flag bit is 0;
[0055] The TBOX time obtaining unit is used to obtain the initial power-on time of the TBOX, and when the time valid flag changes from 1 to 0, obtain the accumulated power-on time before the failure of the TBOX;
[0056] The failure time acquisition unit is used to start the vehicle controller to count the failure accumulation time when the time valid flag is 0;
[0057] an absolute time calculation unit, configured to calculate the absolute time according to the cumulative power-on time before the failure and the cumulative failure time;
[0058] The power-off time calculation unit is used for acquiring the battery working state of the power battery, and calculating the power-off time of the battery according to the battery working state and the absolute time.
[0059] Preferably, the TBOX time acquisition unit is further configured to acquire the effective power-on accumulated time of the TBOX when the time valid flag is 1;
[0060] The absolute time calculation unit is further configured to use the difference between the effective power-on accumulation time and the power-on initial time as the absolute time.
[0061] Preferably, the absolute time calculation unit includes:
[0062] The first calculation unit is configured to use the sum of the cumulative power-on time before the failure and the cumulative failure time as the absolute time when the TBOX fails and recovers during the current power-on process.
[0063] Preferably, the absolute time calculation unit further includes:
[0064] The second calculation unit is used to obtain the difference between the accumulated failure time and the power-off time of the entire vehicle by obtaining the power-off time of the entire vehicle when the TBOX fails during the current power-on process and does not recover. And the sum of the cumulative power-on time before failure and the difference is used as the absolute time.
[0065] It can be seen that the present invention provides a system for calculating the power-off time of a new energy vehicle. The TBOX time valid flag is set by the setting unit, and the TBOX time acquisition unit acquires the accumulated power-on time of the TBOX when the time valid flag is 1, and the invalid time is acquired. When the time valid flag is 0, the unit obtains the cumulative failure time obtained by the vehicle controller, and then calculates the power-off time of the vehicle. It solves the problem that the power-off time of new energy vehicles is mainly monitored and obtained through the on-board terminal TBOX, which is prone to inaccurate acquisition of the power-off time when the TBOX fails, which can improve the safety of the battery management system and the accuracy of battery state estimation.
[0066] The structure, features and effects of the present invention have been described in detail above according to the embodiments shown in the drawings. The above descriptions are only the preferred embodiments of the present invention, but the scope of the present invention is not limited by the drawings. Changes made to the concept of the present invention, or modifications to equivalent embodiments with equivalent changes, shall fall within the protection scope of the present invention as long as they do not exceed the spirit covered by the description and drawings.