A high-voltage power-down method and system for new energy hybrid vehicles

Abstract

The present application relates to a kind of high voltage power-down method and system for new energy hybrid vehicle, wherein, the method comprises: the high voltage system of whole vehicle is divided into main motor drive circuit and auxiliary drive circuit, when vehicle judges to need to the high voltage power-down of main motor drive circuit, the actual current of main motor drive circuit is collected, actual output torque, and it is filtered to obtain filtered current and filtered torque, the validity of filtered current and filtered torque is verified, steady state duration verification is carried out, and the unloading state of main motor is determined, and the result meets the requirements to unlock main motor drive circuit power-down authorization, otherwise, main motor drive circuit power-down authorization is not unlocked.The present application can greatly improve the reliability of main motor high voltage power-down, completely eliminate the power-down jamming caused by auxiliary drive circuit current superposition, determination overtime problem, adapt to hybrid commercial vehicle power-down demand under all conditions.

Description

Technical Field

[0001] This invention relates to the field of high-voltage electric drive technology for new energy hybrid vehicles, and in particular to a high-voltage electric drive method and system for new energy hybrid vehicles. Background Technology

[0002] New energy hybrid commercial vehicles generally adopt a high-voltage centralized power supply scheme. The high-voltage system of the whole vehicle is divided into the main motor drive circuit and auxiliary drive circuits such as steering, braking, and air conditioning. The two types of circuits are powered by independent high-voltage contactors, forming a high-voltage topology structure with decoupled main and auxiliary drives. The current industry-standard high-voltage power-down control strategy uses the total output current of the power battery as the core judgment criterion. Only when the total battery current is detected to drop below the safety threshold is the high-voltage main positive relay allowed to be disconnected and the high-voltage power-down action executed.

[0003] The existing solution has significant technical flaws:

[0004] After the main and auxiliary drive circuits are separated, the battery current is the sum of the currents of the two circuits. The actual working state of the main motor circuit cannot be accurately reflected by the battery current alone. If the auxiliary drive circuit still has a small current output, the battery current will not be able to drop to the threshold, thus hindering the normal disconnection of the main positive relay and affecting the power-down efficiency.

[0005] Therefore, existing technologies cannot meet the power-down logic requirements of high-voltage systems with separate main and auxiliary drive circuits, and there is an urgent need for an optimized high-voltage power-down permission judgment scheme. Summary of the Invention

[0006] Therefore, the technical problem to be solved by the present invention is to overcome the problem that in the prior art, the high voltage power-down of new energy hybrid vehicles is based on the total output current of the power battery (the sum of the main motor drive circuit and the auxiliary drive circuit) as the core criterion, which affects the power-down efficiency.

[0007] To solve the above-mentioned technical problems, the present invention provides a high-voltage power-off method for new energy hybrid vehicles, comprising:

[0008] Step S1: Divide the vehicle's high-voltage system into a main motor drive circuit and an auxiliary drive circuit. When the vehicle determines that it needs to cut off the high voltage of the main motor drive circuit, the actual current of the main motor drive circuit is collected. Actual output torque ;

[0009] Step S2: Measure the actual current of the main motor drive circuit. Actual output torque Perform filtering separately and determine the filtered current. With filtered torque If the data is valid, retain the filtered data; otherwise, return to step S1.

[0010] Step S3: Filter the current The current is compared in real time with the preset current safety threshold, and the filtered torque is simultaneously... The results are compared in real time with the preset torque unloading threshold. If both comparison results meet the preset conditions, proceed to the next step; otherwise, return to step S1.

[0011] Step S4: Set the steady-state determination time. During the steady-state determination time Inside, when the filtered current The torque is compared in real time with the preset current safety threshold and then filtered. If the real-time comparison with the preset torque unloading threshold meets the preset conditions, proceed to the next step; otherwise, re-time and re-verify.

[0012] Step S5: Based on the filtered current With filtered torque Constructing steady-state confidence Based on the steady-state confidence level The current unloading state of the main motor is determined, and if the steady-state confidence level is... If the credibility requirement is met, the power-off authorization for the main motor drive circuit will be unlocked; otherwise, the power-off authorization for the main motor drive circuit will not be unlocked.

[0013] In one embodiment of the present invention, step S2 involves adjusting the actual current of the main motor drive circuit. Actual output torque Perform filtering separately and determine the filtered current. With filtered torque Whether the data is truly valid or not, if it is, the filtered data is retained; if it is not truly valid, the method to return to step S1 includes:

[0014] Based on the actual current With the filtered current Constructing current residual According to the actual output torque With filtered torque Constructing torque residuals According to the current residual and torque residual Determine the filtered current Filtered torque If the data is valid, retain the filtered data; otherwise, return to step S1.

[0015] In one embodiment of the present invention, the step of basing the actual current on... With the filtered current Constructing current residual The formula is:

[0016] ;

[0017] The actual output torque With filtered torque Constructing torque residuals The formula is:

[0018] ;

[0019] in, To take the absolute value.

[0020] In one embodiment of the present invention, the method based on the current residual... and torque residual Determine the filtered current Filtered torque Whether a method is truly effective includes:

[0021] Setting current residual and torque residual Allowable upper limit , ,when and When that happens, determine the filtered current. Filtered torque It must be authentic and valid to pass the validity check; otherwise, it will fail the validity check.

[0022] In one embodiment of the present invention, step S3 filters the current. The current is compared in real time with the preset current safety threshold, and the filtered torque is simultaneously... The method of comparing the result with a preset torque unloading threshold in real time, and proceeding to the next step if both comparison results meet the preset conditions, and otherwise returning to step S1, includes:

[0023] Set preset current safety threshold and preset torque unloading threshold ,when and If the condition is met, proceed to the next step; otherwise, return to step S1.

[0024] In one embodiment of the present invention, step S5 is based on the filtered current. With filtered torque Constructing steady-state confidence The formula is:

[0025] ;

[0026] in, The first and second weighting coefficients and .

[0027] In one embodiment of the present invention, step S5 is based on the steady-state confidence level. The current unloading state of the main motor is determined, and if the steady-state confidence level is... If the trustworthiness requirement is met, the method to unlock the power-down authorization of the main motor drive circuit, and otherwise not to unlock the power-down authorization of the main motor drive circuit includes:

[0028] When steady-state confidence If the credibility is satisfied, the power-off authorization for the main motor drive circuit is unlocked; otherwise, the power-off authorization for the main motor drive circuit is not unlocked.

[0029] To solve the above-mentioned technical problems, the present invention provides a high-voltage power-off system for new energy hybrid vehicles, comprising:

[0030] The data acquisition module is used to divide the vehicle's high-voltage system into a main motor drive circuit and an auxiliary drive circuit. When the vehicle determines that it needs to cut off the high voltage of the main motor drive circuit, it acquires the actual current of the main motor drive circuit. Actual output torque ;

[0031] First judgment module: used to determine the actual current of the main motor drive circuit. Actual output torque Perform filtering separately and determine the filtered current. With filtered torque If the data is valid, retain the filtered data; otherwise, return to step S1.

[0032] Second judgment module: used to process the filtered current The current is compared in real time with the preset current safety threshold, and the filtered torque is simultaneously... The results are compared in real time with the preset torque unloading threshold. If both comparison results meet the preset conditions, proceed to the next step; otherwise, return to step S1.

[0033] Third judgment module: used to set the steady-state judgment duration During the steady-state determination time Inside, when the filtered current The torque is compared in real time with the preset current safety threshold and then filtered. If the real-time comparison with the preset torque unloading threshold meets the preset conditions, proceed to the next step; otherwise, re-time and re-verify.

[0034] The fourth judgment and power-off module: used to determine the power-off status based on the filtered current. With filtered torque Constructing steady-state confidence Based on the steady-state confidence level The current unloading state of the main motor is determined, and if the steady-state confidence level is... If the credibility requirement is met, the power-off authorization for the main motor drive circuit will be unlocked; otherwise, the power-off authorization for the main motor drive circuit will not be unlocked.

[0035] To solve the above-mentioned technical problems, the present invention provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the high-voltage power-off method for new energy hybrid vehicles as described above.

[0036] To solve the above-mentioned technical problems, the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, it implements the steps of the high-voltage power-off method for new energy hybrid vehicles as described above.

[0037] Compared with the prior art, the above-described technical solution of the present invention has the following advantages:

[0038] The high-voltage power-off method for new energy hybrid vehicles described in this invention divides the high-voltage system of the vehicle into a main motor drive circuit and an auxiliary drive circuit. This breaks the industry's long-standing reliance on the total battery current (i.e., the sum of the current in the main motor drive circuit and the current in the auxiliary drive circuit) for power-off design. It eliminates the high-voltage power-off strategy that uses the total battery current for determination, thus avoiding the systemic defects caused by the superposition of currents in multiple branches from the source.

[0039] This invention can significantly improve the reliability of the main motor drive circuit under high voltage, completely eliminate the problems of power-down jamming and judgment timeout caused by the superposition of auxiliary drive current, and adapt to the power-down requirements of hybrid commercial vehicles under all working conditions.

[0040] This invention accurately matches the actual load state of the main motor, and the power-off judgment logic is more in line with the actual working conditions of the high-voltage main circuit, thereby improving the high-voltage safety management level of the whole vehicle. Attached Figure Description

[0041] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0042] Figure 1 This is a flowchart of the method of the present invention. Detailed Implementation

[0043] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0044] Reference Figure 1 As shown, this invention relates to a high-voltage power-off method for new energy hybrid vehicles, comprising:

[0045] Step S1: Divide the vehicle's high-voltage system into a main motor drive circuit and an auxiliary drive circuit. When the vehicle determines that it needs to cut off the high voltage of the main motor drive circuit, the actual current of the main motor drive circuit is collected. Actual output torque ;

[0046] Step S2: Measure the actual current of the main motor drive circuit. Actual output torque Perform filtering separately and determine the filtered current. With filtered torque If the data is valid, retain the filtered data; otherwise, return to step S1.

[0047] Step S3: Filter the current The current is compared in real time with the preset current safety threshold, and the filtered torque is simultaneously... The results are compared in real time with the preset torque unloading threshold. If both comparison results meet the preset conditions, proceed to the next step; otherwise, return to step S1.

[0048] Step S4: Set the steady-state determination time. During the steady-state determination time Inside, when the filtered current The torque is compared in real time with the preset current safety threshold and then filtered. If the real-time comparison with the preset torque unloading threshold meets the preset conditions, proceed to the next step; otherwise, re-time and re-verify.

[0049] Step S5: Based on the filtered current With filtered torque Constructing steady-state confidence Based on the steady-state confidence level The unloading state of the current main motor is determined (unloading state refers to whether the motor is still working; if the motor is completely stopped, unloading is complete). If the steady-state confidence level... If the credibility requirement is met, the power-down authorization for the main motor drive circuit is unlocked; otherwise, it is not unlocked. The function of high-voltage power-down is to safely disconnect the vehicle's high-voltage power supply when the vehicle is stopped, powered down, or malfunctions.

[0050] The following is a detailed description of this embodiment:

[0051] In step S1, this embodiment divides the vehicle's high-voltage system into a main motor drive circuit and an auxiliary drive circuit. The main motor drive circuit is: power battery. Main drive high voltage contactor Motor controller (MCU) The main motor's purpose is to convert the high-voltage DC power from the power battery into AC power to drive the main motor. The auxiliary drive circuit consists of the power battery... Auxiliary high voltage contactor Various auxiliary motor controllers (MCUs) Auxiliary motor. In this embodiment, the high-voltage contactor is a high-voltage relay, which controls the on / off state of high-voltage electricity. The traditional power-down strategy only detects the total battery current. For example, if the main motor drive circuit has stopped (i.e., the main motor drive circuit current is 0), but the auxiliary drive circuit still has a small current, then the total battery current is the sum of the main motor drive circuit current and the auxiliary drive circuit current (not 0). At this time, the system judges that "there is still a load" and refuses to disconnect the main drive high-voltage contactor. This will cause the main motor drive circuit to fail to disconnect in time, resulting in low power-down efficiency and even safety hazards.

[0052] Furthermore, step S2 involves checking the actual current of the main motor drive circuit. Actual output torque First-order low-pass filtering is applied to each part of the vehicle to effectively filter out electromagnetic interference and instantaneous signal jumps caused by motor vibration, thus avoiding misjudgments caused by high-frequency interference.

[0053] Furthermore, step S2 involves checking the actual current of the main motor drive circuit. Actual output torque Perform filtering separately and determine the filtered current. With filtered torque Whether the data is truly valid or not, if it is, the filtered data is retained; if it is not truly valid, the method to return to step S1 includes:

[0054] Based on the actual current With the filtered current Constructing current residual According to the actual output torque With filtered torque Constructing torque residuals According to the current residual and torque residual Determine the filtered current Filtered torque If the data is valid, retain the filtered data; otherwise, return to step S1.

[0055] Furthermore, based on the actual current With the filtered current Constructing current residual The formula is:

[0056] ;

[0057] Furthermore, based on the actual output torque With filtered torque Constructing torque residuals The formula is:

[0058] ;

[0059] in, To take the absolute value.

[0060] Furthermore, based on the current residual and torque residual Determine the filtered current Filtered torque Whether a method is truly effective includes:

[0061] Setting current residual and torque residual Allowable upper limit , ,when and When that happens, determine the filtered current. Filtered torque It must be authentic and valid to pass the validity check; otherwise, it will fail the validity check.

[0062] Further, step S3 will filter the current. The current is compared in real time with the preset current safety threshold, and the filtered torque is simultaneously... The method of comparing the result with a preset torque unloading threshold in real time, and proceeding to the next step if both comparison results meet the preset conditions, and otherwise returning to step S1, includes:

[0063] Set preset current safety threshold and preset torque unloading threshold ,when and If the condition is met, proceed to the next step; otherwise, return to step S1.

[0064] Further, step S5 is based on the filtered current. With filtered torque Constructing steady-state confidence The formula is:

[0065] ;

[0066] in, The first and second weighting coefficients and .

[0067] Further, step S5 is based on the steady-state confidence level. The current unloading state of the main motor is determined, and if the steady-state confidence level is... If the trustworthiness requirement is met, the method to unlock the power-down authorization of the main motor drive circuit, and otherwise not to unlock the power-down authorization of the main motor drive circuit includes:

[0068] When steady-state confidence If the credibility is satisfied, the power-off authorization for the main motor drive circuit is unlocked; otherwise, the power-off authorization for the main motor drive circuit is not unlocked.

[0069] Example 2

[0070] This embodiment provides a high-voltage power-off system for new energy hybrid vehicles, including:

[0071] The data acquisition module is used to divide the vehicle's high-voltage system into a main motor drive circuit and an auxiliary drive circuit. When the vehicle determines that it needs to cut off the high voltage of the main motor drive circuit, it acquires the actual current of the main motor drive circuit. Actual output torque ;

[0072] First judgment module: used to determine the actual current of the main motor drive circuit. Actual output torque Perform filtering separately and determine the filtered current. With filtered torque If the data is valid, retain the filtered data; otherwise, return to step S1.

[0073] Second judgment module: used to process the filtered current The current is compared in real time with the preset current safety threshold, and the filtered torque is simultaneously... The results are compared in real time with the preset torque unloading threshold. If both comparison results meet the preset conditions, proceed to the next step; otherwise, return to step S1.

[0074] Third judgment module: used to set the steady-state judgment duration During the steady-state determination time Inside, when the filtered current The torque is compared in real time with the preset current safety threshold and then filtered. If the real-time comparison with the preset torque unloading threshold meets the preset conditions, proceed to the next step; otherwise, re-time and re-verify.

[0075] The fourth judgment and power-off module: used to determine the power-off status based on the filtered current. With filtered torque Constructing steady-state confidence Based on the steady-state confidence level The current unloading state of the main motor is determined, and if the steady-state confidence level is... If the credibility requirement is met, the power-off authorization for the main motor drive circuit will be unlocked; otherwise, the power-off authorization for the main motor drive circuit will not be unlocked.

[0076] Example 3

[0077] This embodiment provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the high-voltage power-off method for new energy hybrid vehicles described in Embodiment 1.

[0078] Example 4

[0079] This embodiment provides a computer-readable storage medium storing a computer program thereon. When the computer program is executed by a processor, it implements the steps of the high-voltage power-off method for new energy hybrid vehicles described in Embodiment 1.

[0080] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of this application can be implemented in various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0081] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0082] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0083] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0084] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A high-voltage power-off method for new energy hybrid vehicles, characterized in that, include: Step S1: Divide the vehicle's high-voltage system into a main motor drive circuit and an auxiliary drive circuit. When the vehicle determines that it needs to cut off the high voltage of the main motor drive circuit, the actual current of the main motor drive circuit is collected. Actual output torque ; Step S2: Measure the actual current of the main motor drive circuit. Actual output torque Perform filtering separately and determine the filtered current. With filtered torque If the data is valid, retain the filtered data; otherwise, return to step S1. Step S3: Filter the current The current is compared in real time with the preset current safety threshold, and the filtered torque is simultaneously... The results are compared in real time with the preset torque unloading threshold. If both comparison results meet the preset conditions, proceed to the next step; otherwise, return to step S1. Step S4: Set the steady-state determination time. During the steady-state determination time Inside, when the filtered current The torque is compared in real time with the preset current safety threshold and then filtered. If the real-time comparison with the preset torque unloading threshold meets the preset conditions, proceed to the next step; otherwise, re-time and re-verify. Step S5: Based on the filtered current With filtered torque Constructing steady-state confidence Based on the steady-state confidence level The current unloading state of the main motor is determined, and if the steady-state confidence level is... If the credibility requirement is met, the power-off authorization for the main motor drive circuit will be unlocked; otherwise, the power-off authorization for the main motor drive circuit will not be unlocked.

2. The high-voltage power-off method for new energy hybrid vehicles according to claim 1, characterized in that: Step S2 involves checking the actual current of the main motor drive circuit. Actual output torque Perform filtering separately and determine the filtered current. With filtered torque If the data is true and valid, then retain the filtered data. If the result is not valid, the methods to return to step S1 include: Based on the actual current With the filtered current Constructing current residual According to the actual output torque With filtered torque Constructing torque residuals According to the current residual and torque residual Determine the filtered current Filtered torque If the data is true and valid, then retain the filtered data. If it is not true and valid, return to step S1.

3. The high-voltage power-off method for new energy hybrid vehicles according to claim 2, characterized in that: The statement based on actual current With the filtered current Constructing current residual The formula is: ； The actual output torque With filtered torque Constructing torque residuals The formula is: ； in, To take the absolute value.

4. The high-voltage power-off method for new energy hybrid vehicles according to claim 2, characterized in that: The current residual and torque residual Determine the filtered current Filtered torque Methods that are truly effective include: Setting current residual and torque residual Allowable upper limit , ,when and When that happens, determine the filtered current. Filtered torque It must be authentic and valid to pass the validity check; otherwise, it will fail the validity check.

5. The high-voltage power-off method for new energy hybrid vehicles according to claim 1, characterized in that: Step S3 filters the current. The current is compared in real time with the preset current safety threshold, and the filtered torque is simultaneously... The method of comparing the result with a preset torque unloading threshold in real time, and proceeding to the next step if both comparison results meet the preset conditions, and otherwise returning to step S1, includes: Set preset current safety threshold and preset torque unloading threshold ,when and If the condition is met, proceed to the next step; otherwise, return to step S1.

6. The high-voltage power-off method for new energy hybrid vehicles according to claim 1, characterized in that: Step S5 is based on the filtered current. With filtered torque Constructing steady-state confidence The formula is: ； in, The first and second weighting coefficients and .

7. The high-voltage power-off method for new energy hybrid vehicles according to claim 1, characterized in that: Step S5 is based on the steady-state confidence level. The current unloading state of the main motor is determined, and if the steady-state confidence level is... If the trustworthiness requirement is met, the method to unlock the power-down authorization of the main motor drive circuit, and otherwise not to unlock the power-down authorization of the main motor drive circuit includes: When steady-state confidence If the credibility is satisfied, the power-off authorization for the main motor drive circuit is unlocked; otherwise, the power-off authorization for the main motor drive circuit is not unlocked.

8. A high-voltage power-off system for new energy hybrid vehicles, characterized in that, include: The data acquisition module is used to divide the vehicle's high-voltage system into a main motor drive circuit and an auxiliary drive circuit. When the vehicle determines that it needs to cut off the high voltage of the main motor drive circuit, it acquires the actual current of the main motor drive circuit. Actual output torque ; First judgment module: used to determine the actual current of the main motor drive circuit. Actual output torque Perform filtering separately and determine the filtered current. With filtered torque If the data is valid, retain the filtered data; otherwise, return to step S1. Second judgment module: used to process the filtered current The current is compared in real time with the preset current safety threshold, and the filtered torque is simultaneously... The results are compared in real time with the preset torque unloading threshold. If both comparison results meet the preset conditions, proceed to the next step; otherwise, return to step S1. Third judgment module: used to set the steady-state judgment duration During the steady-state determination time Inside, when the filtered current The torque is compared in real time with the preset current safety threshold and then filtered. If the real-time comparison with the preset torque unloading threshold meets the preset conditions, proceed to the next step; otherwise, re-time and re-verify. The fourth judgment and power-off module: used to determine the power-off status based on the filtered current. With filtered torque Constructing steady-state confidence Based on the steady-state confidence level The current unloading state of the main motor is determined, and if the steady-state confidence level is... If the credibility requirement is met, the power-off authorization for the main motor drive circuit will be unlocked; otherwise, the power-off authorization for the main motor drive circuit will not be unlocked.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, it implements the steps of the high-voltage power-off method for new energy hybrid vehicles as described in any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by the processor, it implements the steps of the high-voltage power-off method for new energy hybrid vehicles as described in any one of claims 1 to 7.

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