A method for fault diagnosis of electric vehicle

Abstract

The present invention provides an electric vehicle fault diagnosis method, comprising the following steps: S1, collecting signals of each electric vehicle node and establishing a node state function; S2, calculating the node state vector and fault conduction time according to the power and signal transmission sequence of the node; S3, comparing the node state vector and state function; if only one node's state vector is the same as the state function, the node is determined to be faulty; if the state vectors of multiple nodes are the same as the state function, then after checking the nodes with long fault conduction time, the node state vector and state function are compared again. Beneficial effects of the present invention: By establishing the node state function and state vector, and calculating the fault conduction time, the method can accurately locate the faulty node and reduce the possibility of misdiagnosis.

Description

Technical Field

[0001] The invention belongs to the technical field of electric vehicle fault diagnosis, and in particular relates to an electric vehicle fault diagnosis method. Background Art

[0002] The trial operation of self-driving electric vehicles has made early fault diagnosis of electric vehicles particularly important. Traditional manually driven vehicle drivers or vehicle maintenance personnel act as vehicle fault diagnosing personnel based on their own experience. Passengers of self-driving vehicles do not necessarily have experience in diagnosing vehicles, nor do they need to be responsible for vehicle diagnosis. Early fault diagnosis of electric vehicles is particularly important for self-driving vehicles, and current electric vehicle fault diagnosis methods are mostly based on experience. Therefore, a fast and accurate method for electric vehicle fault diagnosis is urgently needed. Summary of the invention

[0003] In view of this, the present invention aims to provide an electric vehicle fault diagnosis method, in order to solve at least one of the above-mentioned technical problems.

[0004] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0005] A first aspect of the present invention provides an electric vehicle fault diagnosis method, comprising the following steps:

[0006] S1, collect the signals of each electric vehicle node and establish the node state function;

[0007] S2, calculate the node state vector and fault conduction time according to the power and signal transmission sequence of the node;

[0008] S3, compare the state vector and state function of the node;

[0009] If only one node’s state vector is identical to the state function, the node is considered faulty;

[0010] If the state vectors and state functions of multiple nodes are the same, after troubleshooting the nodes with long fault transmission time, compare the state vectors and state functions of the nodes again.

[0011] Furthermore, in S2, an abnormal signal transfer matrix is ​​established according to the power and signal transmission order of the nodes, and a state vector is calculated according to the abnormal signal transfer matrix and the state function.

[0012] Furthermore, in S3, the auxiliary circuit is firstly diagnosed for faults, and after the faults of the auxiliary circuit are eliminated, the main control circuit is diagnosed for faults.

[0013] Furthermore, the specific process of fault diagnosis of the auxiliary circuit is as follows:

[0014] S31, comparing the state vector and state function of each node in the auxiliary loop;

[0015] If only one node’s state vector is identical to the state function, the node is considered faulty;

[0016] If the state vectors and state functions of multiple nodes are the same, after troubleshooting the nodes with long fault conduction times, compare the state vectors and state functions of the nodes again until the nodes in the auxiliary loop are fault-free.

[0017] Furthermore, the specific process of fault diagnosis of the main control circuit is as follows:

[0018] S32, performing zero-filling processing on the state matrix of each node in the main control loop according to the connection state matrix between the auxiliary loop and the main control loop;

[0019] S33, using the state matrix after zero filling processing, according to the abnormal signal transmission matrix, the state matrix and the connection state matrix to calculate the state vector of the main control loop;

[0020] S34, comparing the state vector and state function of each node in the main control loop;

[0021] If only one node’s state vector is identical to the state function, the node is considered faulty;

[0022] If the state vectors and state functions of multiple nodes are the same, after troubleshooting the nodes with long fault conduction time, compare the state vectors and state functions of the nodes again until no nodes in the main control loop are faulty.

[0023] A second aspect of the present invention provides an electric vehicle fault diagnosis device, comprising:

[0024] A collection module, which is configured to collect signals from each electric vehicle node;

[0025] A calculation module is configured to establish a node state function according to the collected electric vehicle node signal; calculate the node state vector and fault conduction time according to the power and signal transmission sequence of the node;

[0026] The analysis module is configured to compare the state vector of the node with the state function; if the state vector of only one node is the same as the state function, the node is determined to be faulty; if the state vectors of multiple nodes are the same as the state function, the node with a long fault conduction time is determined to be faulty.

[0027] Furthermore, if the state vectors and state functions of multiple nodes are the same, the node with a long fault conduction time is determined to be faulty, and the fault is eliminated by continuing to compare the state vectors and state functions of the nodes until the fault is eliminated.

[0028] A third aspect of the present invention provides an electronic device, comprising a processor and a memory that is communicatively connected to the processor and is used to store instructions executable by the processor, wherein the processor is used to execute the method described in the first aspect above.

[0029] The fourth aspect of the present invention provides a server, comprising at least one processor, and a memory communicatively connected to the processor, the memory storing instructions executable by the at least one processor, the instructions being executed by the processor so that the at least one processor executes the method described in the first aspect.

[0030] A fifth aspect of the present invention provides a computer-readable storage medium storing a computer program, which implements the method described in the first aspect when executed by a processor.

[0031] Compared with the prior art, the electric vehicle fault diagnosis method described in the present invention has the following beneficial effects:

[0032] (1) The electric vehicle fault diagnosis method described in the present invention can accurately locate the fault node by establishing a node state function and a state vector and calculating the fault conduction time, thereby reducing the possibility of misdiagnosis.

[0033] (2) The electric vehicle fault diagnosis method described in the present invention can quickly eliminate faults in non-critical areas by diagnosing the auxiliary circuit first and then the main control circuit, focusing on the part that is most likely to have problems, thereby improving diagnostic efficiency.

[0034] (3) In the electric vehicle fault diagnosis method described in the present invention, the zero-filling process is to ensure that when the data of the auxiliary loop is insufficient to fully describe the state of the main control loop, the state matrix of the main control loop can remain complete so as to perform accurate state vector calculation. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0036] Figure 1 A schematic diagram of a fault diagnosis method according to an embodiment of the present invention;

[0037] Figure 2 This is a schematic diagram of power and signal flow according to an embodiment of the present invention. DETAILED DESCRIPTION

[0038] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0039] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0040] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0041] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments. Embodiment 1

[0042] like Figure 1 As shown, a method for diagnosing faults in an electric vehicle comprises the following steps:

[0043] According to the electrical circuit diagram, power and signal transmission diagram, the power and signal transmission sequence of the node and the power and signal fault transmission matrix are obtained. The main control circuit is the circuit that plays a major role in realizing the system function, and the auxiliary circuit is the circuit that plays an auxiliary role in order to realize the function of the main circuit.

[0044] S1, collect the signals of each electric vehicle node and establish the node state function;

[0045] S2, calculate the node state vector and fault conduction time according to the power and signal transmission sequence of the node;

[0046] S3, compare the state vector and state function of the node;

[0047] If only one node’s state vector is identical to the state function, the node is considered faulty;

[0048] If the state vectors and state functions of multiple nodes are the same, after troubleshooting the nodes with long fault transmission time, compare the state vectors and state functions of the nodes again.

[0049] In the S2, an abnormal signal transmission matrix is ​​established according to the power and signal transmission order of the node, and a state vector is calculated according to the abnormal signal transmission matrix and the state function.

[0050] In S3, the auxiliary circuit is firstly diagnosed for faults, and after the faults of the auxiliary circuit are eliminated, the main control circuit is diagnosed for faults.

[0051] The specific process of fault diagnosis of auxiliary circuit is as follows:

[0052] S31, comparing the state vector and state function of each node in the auxiliary loop;

[0053] If only one node’s state vector is identical to the state function, the node is considered faulty;

[0054] If the state vectors and state functions of multiple nodes are the same, after troubleshooting the nodes with long fault conduction times, compare the state vectors and state functions of the nodes again until the nodes in the auxiliary loop are fault-free.

[0055] The specific process of fault diagnosis of the main control circuit is as follows:

[0056] S32, performing zero-filling processing on the state matrix of each node in the main control loop according to the connection state matrix between the auxiliary loop and the main control loop;

[0057] According to the connection state matrix between the auxiliary loop and the main control loop, the state matrix of each node in the main control loop is filled with zeros. If a node has no directly corresponding node or data in the auxiliary loop, the corresponding position in the state matrix will be filled with zeros.

[0058] Before performing fault diagnosis on the main control loop, it is necessary to consider the connection relationship between the auxiliary loop and the main control loop. Zero padding is to ensure that when the data of the auxiliary loop is insufficient to fully describe the state of the main control loop, the state matrix of the main control loop can remain complete for accurate state vector calculation.

[0059] S33, using the state matrix after zero filling processing, according to the abnormal signal transmission matrix, the state matrix and the connection state matrix to calculate the state vector of the main control loop;

[0060] S34, comparing the state vector and state function of each node in the main control loop;

[0061] If only one node’s state vector is identical to the state function, the node is considered faulty;

[0062] If the state vectors and state functions of multiple nodes are the same, after troubleshooting the nodes with long fault conduction time, compare the state vectors and state functions of the nodes again until no nodes in the main control loop are faulty.

[0063] An electric vehicle fault diagnosis device, comprising:

[0064] A collection module, which is configured to collect signals from each electric vehicle node;

[0065] A calculation module is configured to establish a node state function according to the collected electric vehicle node signal; calculate the node state vector and fault conduction time according to the power and signal transmission sequence of the node;

[0066] The analysis module is configured to compare the state vector of the node with the state function; if the state vector of only one node is the same as the state function, the node is determined to be faulty; if the state vectors of multiple nodes are the same as the state function, the node with a long fault conduction time is determined to be faulty.

[0067] If the state vectors and state functions of multiple nodes are the same, the node with the longest fault conduction time is determined to be faulty. The fault is eliminated and the state vectors and state functions of the nodes are continuously compared until the fault is eliminated.

[0068] Take the steering system of an electric vehicle as an example:

[0069] The matrix model S that defines abnormal states and node (part) failures i :

[0070] ;

[0071] Among them, Si is the actual measured value, Normal value: (1,0,0) T ,Lower value: (0,1,0) T , High value: (0,0,1) T

[0072] Define the abnormal signal transmission matrix J from node i to node i+1;

[0073] Si+1=JSi;

[0074] Upstream status is passed down

[0075] The formulas for transfer characteristics Si:Normal=>Si+1:Normal, Si:Lower=>Si+1:Lower, Si:High=>Si+1:High, and J are as follows:

[0076] ;

[0077] Calculate the column vector P of all nodes on the line, P=[S1,...,Si,...,Sn] is the actual state of each node at the current moment, and n is the number of summary points.

[0078] The state vector of each node when node i is faulty is calculated by the following equation:

[0079] Qi=[S1,...,Si-1,Si,JSi,...,Jn-iSi];

[0080] 1≦i≦n;

[0081] Collect and obtain the node state matrix P2 of the auxiliary loop;

[0082] High-level alarm;

[0083] ;

[0084] Calculate Q 21 , Q 22 , Q 23 The process is as follows:

[0085] ;

[0086] ;

[0087] ;

[0088] Q 21 , Q 22 , Q 23 Same as P2,

[0089] Calculate the fault transmission time of each node, the transmission time W 21 (>W 22 、>W 23 ) is larger, then F 21 Fault, staff confirmed F 21 After the fault is corrected, repeat the above steps until all abnormalities are eliminated.

[0090] like Figure 2 As shown, the abnormal information of Main-loop is that the status of nodes F1 and F2 is high, and the status of F3, F4, and F5 is low.

[0091] After eliminating the fault in the auxiliary circuit, the connection status between the auxiliary circuit and the main control circuit is as follows:

[0092] ;

[0093] ;

[0094] ;

[0095] Refer to the method of image recognition by convolutional neural network, and perform zero padding on the matrix before calculation.

[0096] The calculation process of zero padding is as follows:

[0097] ;

[0098] Calculate Q1, Q2, Q3, Q4, Q5 in sequence;

[0099] Taking Q2 as an example, the calculation process is as follows:

[0100]

[0101] ;

[0102] The abnormal transmission time W3 (>W4,>W5) of S3 is the longest, and F3 is abnormal.

[0103] By establishing node state functions and state vectors, and calculating fault conduction time, this method can accurately locate the faulty node and reduce the possibility of misdiagnosis.

[0104] By diagnosing the auxiliary circuit first and then the main control circuit, faults in non-critical areas can be quickly eliminated, and attention can be focused on the parts that are most likely to have problems, thereby improving diagnostic efficiency.

[0105] It can be adjusted according to different electric vehicle models and system designs, and is suitable for a variety of electric vehicle systems with strong adaptability.

[0106] By using mathematical models and algorithms to analyze node status, this method realizes the automation and intelligence of fault diagnosis to a certain extent, reducing the need for human intervention.

[0107] Embodiment 2:

[0108] An electronic device comprises a processor and a memory which is communicatively connected to the processor and is used to store instructions executable by the processor, wherein the processor is used to execute the method described in the first embodiment above.

[0109] Embodiment three:

[0110] A server includes at least one processor and a memory communicatively connected to the processor, wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the processor so that the at least one processor executes the method described in Example 1.

[0111] Embodiment 4:

[0112] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method described in embodiment 1 is implemented.

[0113] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

[0114] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for diagnosing electric vehicle faults, characterized in that: The following steps are involved: S1, collect the signals of each electric vehicle node and establish the node state function; S2, calculate the node state vector and fault conduction time according to the power and signal transmission sequence of the node; S3, compare the state vector and state function of the node; If only one node’s state vector is identical to the state function, the node is considered faulty; If the state vectors and state functions of multiple nodes are the same, then after troubleshooting the nodes with the longest fault transmission time, compare the state vectors and state functions of the nodes again; In S3, the auxiliary circuit is firstly diagnosed for faults, and after the faults of the auxiliary circuit are eliminated, the main control circuit is diagnosed for faults; The specific process of fault diagnosis of the main control circuit is as follows: S32, performing zero-filling processing on the state matrix of each node in the main control loop according to the connection state matrix between the auxiliary loop and the main control loop; S33, using the state matrix after zero filling processing, according to the abnormal signal transmission matrix, the state matrix and the connection state matrix to calculate the state vector of the main control loop; S34, comparing the state vector and state function of each node in the main control loop; If only one node’s state vector is identical to the state function, the node is considered faulty; If the state vectors and state functions of multiple nodes are the same, after troubleshooting the nodes with long fault conduction time, compare the state vectors and state functions of the nodes again until no nodes in the main control loop are faulty.

2. The electric vehicle fault diagnosis method according to claim 1, characterized in that: In the S2, an abnormal signal transmission matrix is ​​established according to the power and signal transmission order of the node, and a state vector is calculated according to the abnormal signal transmission matrix and the state function.

3. The electric vehicle fault diagnosis method according to claim 1, characterized in that: The specific process of fault diagnosis of auxiliary circuit is as follows: S31, comparing the state vector and state function of each node in the auxiliary loop; If only one node’s state vector is identical to the state function, the node is considered faulty; If the state vectors and state functions of multiple nodes are the same, after troubleshooting the nodes with long fault conduction times, compare the state vectors and state functions of the nodes again until the nodes in the auxiliary loop are fault-free.

4. An electric vehicle fault diagnosis device, characterized in that: include: A collection module, which is configured to collect signals from each electric vehicle node; A calculation module is configured to establish a node state function according to the collected electric vehicle node signal; calculate the node state vector and fault conduction time according to the power and signal transmission sequence of the node; An analysis module is configured to compare a state vector of a node with a state function; if the state vector of only one node is the same as the state function, the node is determined to be faulty; if the state vectors of multiple nodes are the same as the state function, the node with a long fault conduction time is determined to be faulty; First, perform fault diagnosis on the auxiliary circuit. After eliminating the fault of the auxiliary circuit, perform fault diagnosis on the main control circuit. The specific process of fault diagnosis of the main control circuit is as follows: According to the connection state matrix between the auxiliary loop and the main control loop, the state matrix of each node in the main control loop is zero-filled; Using the state matrix after zero filling, the state vector of the main control loop is calculated according to the abnormal signal transmission matrix, the state matrix and the connection state matrix; Compare the state vector and state function of each node in the main control loop; If only one node’s state vector is identical to the state function, the node is considered faulty; If the state vectors and state functions of multiple nodes are the same, after troubleshooting the nodes with long fault conduction time, compare the state vectors and state functions of the nodes again until no nodes in the main control loop are faulty.

5. The electric vehicle fault diagnosis device according to claim 4, characterized in that: If the state vectors and state functions of multiple nodes are the same, the node with the longest fault conduction time is determined to be faulty. The fault is eliminated and the state vectors and state functions of the nodes are continuously compared until the fault is eliminated.

6. An electronic device, comprising a processor and a memory connected to the processor for storing instructions executable by the processor, characterized in that: The processor is used to execute the method described in any one of claims 1 to 3.

7. A server, characterized in that: It includes at least one processor and a memory communicatively connected to the processor, wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the processor so that the at least one processor executes the method according to any one of claims 1-3.

8. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 3 is implemented.

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