A vehicle start-stop battery connection state detection method and system

Abstract

The application discloses a vehicle start-stop battery connection state detection method and system, and belongs to the technical field of battery connection state detection. The method comprises the following steps: collecting voltage and current data before and after starting, and time sequence data of voltage, current and temperature within a preset starting duration; calculating four start-stop battery connection state detection features according to the collected data; the first feature represents the conduction performance of the start-stop battery connection in the current maximum value within the starting duration; the second feature represents the overall situation of the external connection resistance within the starting duration; the third feature represents the basic conduction performance of the start-stop battery connection after starting; and the fourth feature represents the polarization characteristic of the start-stop battery itself. According to the start-stop battery connection state detection features, the vehicle start-stop battery connection state is judged, including: judging whether a mechanical looseness fault occurs or not; and judging whether a corrosion aging fault occurs or not. The application can solve the problem that there is no reliable vehicle start-stop battery connection state detection method.

Description

Technical Field

[0001] This invention belongs to the field of battery connection status detection technology, specifically relating to a method and system for detecting the connection status of a vehicle start-stop battery. Background Technology

[0002] In commercial heavy trucks, 24V or 12V start-stop batteries power the engine, motor, steering pump, body controller, and various sensors. The positive and negative terminals, grounding points, and main fuse terminals form the main power supply circuit. The reliability of the main power supply circuit connection directly determines the vehicle's safety and uptime.

[0003] Common faults in the main power supply circuit include sudden mechanical loosening and long-term corrosion aging. Sudden mechanical loosening or long-term corrosion aging can lead to increased external connection resistance, causing problems such as excessive starting voltage drop, weak starting failure, continuous overheating and fire, and increased transmission losses. Long-term corrosion aging can also affect the polarization characteristics of the start-stop battery. Common methods for detecting the connection status of vehicle start-stop batteries include: voltage drop empirical method, temperature monitoring method, and battery management system testing.

[0004] The voltage drop empirical method relies on manual periodic checks of voltage drop and on experience to judge whether the wiring is loose. However, the remaining battery charge and the internal resistance of the cell itself will also change the circuit voltage. It is difficult to distinguish whether the voltage drop comes from the cell itself or poor contact caused by mechanical loosening. The voltage drop empirical method cannot diagnose the connection status in real time, nor can it detect micro-corrosion inside the battery.

[0005] Temperature monitoring requires the installation of temperature sensors and leads at the connection terminals of the start-stop battery. However, since the external connection resistance increases first, the continuous heat accumulation only triggers an alarm when the temperature reaches a certain level. By this time, the fault is already quite serious, lacking early warning. In addition, the added temperature sensor only collects temperature values ​​and cannot determine whether the terminal itself is mechanically loose and overheating, or whether external heat sources such as the motor, radiator, or high ambient temperature are baking the terminal, which can easily lead to a large number of false alarms.

[0006] Traditional battery management systems can only calculate the total internal resistance of the main power supply circuit and cannot isolate the external connection resistance. The total internal resistance of the main power supply circuit includes the internal resistance of the start-stop battery itself and the external connection resistance. The battery management system can detect an increase in the total internal resistance of the main power supply circuit, but it cannot determine whether the increase is due to cell aging or poor contact of the external terminals. Therefore, traditional battery management systems cannot fully diagnose the connection status and health of the start-stop battery and cannot identify mechanical loosening faults in the connection terminals.

[0007] Each of the above three methods has its drawbacks, and there is currently a lack of reliable methods for detecting the connection status of vehicle start-stop batteries. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method and system for detecting the connection status of a vehicle start-stop battery, thereby solving the problem of the lack of a reliable method for detecting the connection status of a vehicle start-stop battery.

[0009] To solve the above-mentioned technical problems, the present invention is implemented using the following technical solution:

[0010] In a first aspect, the present invention provides a method for detecting the connection status of a vehicle start-stop battery, comprising:

[0011] Collect voltage and current data before and after startup, as well as time-series data of voltage, current and temperature within a preset startup duration;

[0012] Based on the collected data, four start-stop battery connection status detection features are calculated; the first feature characterizes the conductivity of the start-stop battery connection at the maximum current during the start-up period; the second feature characterizes the overall situation of the external connection resistance during the start-up period; the third feature characterizes the basic conductivity of the start-stop battery connection after start-up; and the fourth feature characterizes the polarization characteristics of the start-stop battery itself.

[0013] The connection status of the vehicle's start-stop battery is determined based on the detection characteristics of the start-stop battery connection status; the determination of the connection status of the vehicle's start-stop battery includes: determining whether a mechanical loosening fault has occurred; determining whether a corrosion aging fault has occurred.

[0014] The aforementioned method for detecting the connection status of a vehicle start-stop battery includes the voltage and current data before and after startup, which include: the static stable open-circuit voltage of the start-stop battery and the initial static current of the main power supply circuit measured before startup, and the steady-state voltage across the start-stop battery and the steady-state current of the main power supply circuit measured after startup.

[0015] The timing data of voltage, current, and temperature include: the voltage across the start-up and stop batteries, the current in the main power supply circuit, and the corresponding start-up and stop battery temperature at various times during the current startup process.

[0016] The aforementioned vehicle start-stop battery connection status detection method calculates a first feature and a second feature based on the collected data, including:

[0017] Based on the timing data of voltage, current and temperature within the preset startup time, calculate the total internal resistance of the main power supply circuit at each moment during the current startup process;

[0018] Calculate the external connection resistance at each time step based on the total internal resistance of the main power supply circuit at each time step.

[0019] Based on the external connection resistance within the preset startup time, calculate the corresponding first feature and second feature; the first feature is the peak connection resistance, and the second feature is the average external connection resistance.

[0020] Peak connection resistance R at each startup peak_connection The calculation formula is:

[0021] R peak_connection =R peak -R cell (I peak ,T peak ),

[0022] In the formula, R peak R is the maximum total internal resistance of the main power supply circuit for each startup. cell (I peak ,T peak The maximum current I in the main power supply circuit during each startup is... peak The corresponding internal resistance of the start-stop battery, T peak The maximum current I in the main power supply circuit during each startup. peak The recorded start-stop battery temperature, R cell (I peak ,T peak ) through I peak and T peak The mapping table of the internal resistance of the start-stop battery body is obtained by querying the pre-acquired mapping table;

[0023] Average external connection resistance R during each startup aver_connection This is the average value of the external connection resistance at all times within the preset startup duration.

[0024] The aforementioned method for detecting the connection status of a vehicle start-stop battery, at time t, the external connection resistor R connection The formula for calculating (t) is:

[0025] R connection (t)=R total (t)-R cell (t),

[0026] In the formula, R total (t) represents the total internal resistance of the main power supply circuit at time t; R cell R(t) is the internal resistance of the start-stop battery at time t. Based on the current in the main power supply circuit at time t and the temperature of the start-stop battery, R is obtained by consulting a pre-obtained mapping table of the internal resistance of the start-stop battery. cell (t); t is the time sequence number within the preset startup duration;

[0027] The total internal resistance R of the main power supply circuit at time t total The formula for calculating (t) is as follows:

[0028] R total (t)=ΔU(t) / ΔI(t),

[0029] In the formula, ΔU(t) represents the voltage change of the battery at time t when it is turned on and off; ΔU(t) = U ocv -U(t), U ocv Let U(t) be the static stable open-circuit voltage of the start-stop battery, and let U(t) be the voltage across the start-stop battery at time t; let ΔI(t) be the change in current in the main power supply circuit at time t, and let ΔI(t) = I(t) - I ocv The initial static current I of the main power supply circuit ocv I(t) is 0, and I(t) is the current in the main power supply circuit at time t.

[0030] The aforementioned vehicle start-stop battery connection status detection method calculates a third feature and a fourth feature based on the collected data, including:

[0031] Based on the voltage and current data before and after startup, the third and fourth characteristics are calculated; the third characteristic is the steady-state connection resistance, and the fourth characteristic is the voltage recovery time.

[0032] Steady-state connection resistor R at each startup con_static The calculation formula is:

[0033] R con_static =(U ocv -U load ) / I load ,

[0034] In the formula, U ocv The static stable open-circuit voltage of the start-stop battery; U load This refers to the steady-state voltage across the battery terminals for starting and stopping; I load This refers to the steady-state current of the main power supply circuit.

[0035] The voltage recovery time for each startup is the time required for the voltage across the start-stop battery to recover to the steady-state voltage of the start-stop battery at the end of the preset startup duration.

[0036] The aforementioned method for detecting the connection status of a vehicle start-stop battery, wherein determining the connection status of the vehicle start-stop battery based on the detection characteristics of the start-stop battery connection status includes:

[0037] If the number of times the increase in the average value of peak connection resistance, steady-state connection resistance and external connection resistance exceeds the preset short-term increase threshold reaches the preset number threshold, and the voltage recovery time is less than the preset voltage recovery time threshold, then a mechanical loosening fault is determined to have occurred.

[0038] If, within the preset total cycle, the average value of the peak connection resistance, steady-state connection resistance, and external connection resistance measured in each sub-cycle is greater than the increase in the average value of the peak connection resistance, steady-state connection resistance, and external connection resistance measured in the previous sub-cycle, compared to the increase in the average value of the peak connection resistance, steady-state connection resistance, and external connection resistance measured in the previous sub-cycle, exceeds the preset long-term increase threshold, and the voltage recovery time of the last startup within the preset total cycle is greater than or equal to the preset voltage recovery time threshold, then a corrosion aging fault is determined to have occurred.

[0039] In the aforementioned vehicle start-stop battery connection status detection method, the increase in the average values ​​of peak connection resistance, steady-state connection resistance, and external connection resistance exceeding a preset short-term increase threshold means that:

[0040] The peak connection resistance is compared with the reference peak connection resistance, the steady-state connection resistance is compared with the reference steady-state connection resistance, and the average external connection resistance is compared with the average external connection resistance. The reference peak connection resistance, reference steady-state connection resistance, and average external connection resistance are measured according to the vehicle's factory calibration or after the most recent standardized maintenance.

[0041] Alternatively, compare the current peak connection resistance with the previous peak connection resistance, compare the current steady-state connection resistance with the previous steady-state connection resistance, and compare the average external connection resistance of the current external connection resistance with the average external connection resistance of the previous external connection resistance.

[0042] The aforementioned method for detecting the connection status of a vehicle start-stop battery also includes: outputting corresponding warning information based on the first feature and a pre-set warning mechanism;

[0043] The pre-set early warning mechanism includes:

[0044] The warning levels are divided into three levels based on the increase of the first feature relative to the first feature benchmark value; the first feature benchmark value is obtained based on the vehicle's factory calibration or after the most recent standardized maintenance.

[0045] The first-level warning is: when the increase of the first feature relative to the first feature baseline value is within the first range, a fault prompt is output;

[0046] The level 2 warning is as follows: when the increase of the first feature relative to the first feature benchmark value falls within the second range, an appropriate maintenance reminder will be output.

[0047] The Level 3 warning is as follows: when the increase of the first feature relative to the first feature benchmark value falls within the third range, an immediate repair prompt is output.

[0048] Secondly, the present invention provides a vehicle start-stop battery connection status detection system, including a voltage sensor, a current sensor, a temperature sensor, an on-board computing unit, and a vehicle controller.

[0049] The voltage sensor and the current sensor are used to collect voltage and current data before and after startup, as well as timing data of voltage and current within a preset startup duration, respectively.

[0050] The temperature sensor is used to collect time-series temperature data within a preset start-up time.

[0051] The on-board computing unit is used to calculate four start-stop battery connection status detection features based on the collected data; the first feature represents the conductivity of the start-stop battery connection at the maximum current during the start-up period; the second feature represents the overall situation of the external connection resistance during the start-up period; the third feature represents the basic conductivity of the start-stop battery connection after start-up; and the fourth feature represents the polarization characteristics of the start-stop battery itself.

[0052] The vehicle controller is used to determine the connection status of the vehicle start-stop battery based on the detection characteristics of the start-stop battery connection status; the determination of the connection status of the vehicle start-stop battery includes: determining whether a mechanical loosening fault has occurred; determining whether a corrosion aging fault has occurred.

[0053] The aforementioned vehicle start-stop battery connection status detection system, wherein the vehicle controller is further configured to output corresponding warning information based on the first feature and a pre-set warning mechanism; the pre-set warning mechanism includes:

[0054] The warning levels are divided into three levels based on the increase of the first feature relative to the first feature benchmark value; the first feature benchmark value is obtained based on the vehicle's factory calibration or after the most recent standardized maintenance.

[0055] The first-level warning is: when the increase of the first feature relative to the first feature baseline value is within the first range, a fault prompt is output;

[0056] The level 2 warning is as follows: when the increase of the first feature relative to the first feature benchmark value falls within the second range, an appropriate maintenance reminder will be output.

[0057] The Level 3 warning is as follows: when the increase of the first feature relative to the first feature benchmark value falls within the third range, an immediate repair prompt is output.

[0058] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0059] The vehicle start-stop battery connection status detection method of the present invention reuses the vehicle's original hardware equipment to collect voltage, current and temperature, calculate the start-stop battery connection status detection characteristics for each start, and determine whether the vehicle start-stop battery connection status is in a mechanical loosening fault or a corrosion aging fault through four start-stop battery connection status detection characteristics, thus solving the problem of lacking a reliable vehicle start-stop battery connection status detection method.

[0060] The vehicle start-stop battery connection status detection method of the present invention uses four start-stop battery connection status detection features calculated for each start-up to judge mechanical loosening faults and corrosion aging faults from multiple dimensions. This solves the problem that existing methods cannot distinguish between mechanical loosening faults and corrosion aging faults, making it easier for staff to locate the cause of the fault and carry out repairs. At the same time, the vehicle start-stop battery connection status detection method of the present invention adopts different judgment criteria for sudden mechanical loosening faults and long-term corrosion aging faults, thereby improving the accuracy of vehicle start-stop battery connection status detection.

[0061] The vehicle start-stop battery connection status detection method of the present invention measures and detects the data of each start-up, and can detect and distinguish mechanical loosening faults and corrosion aging faults of the vehicle start-stop battery connection status based on the real-time data of each vehicle start-up, thereby improving the timeliness of vehicle start-stop battery connection status detection.

[0062] The vehicle start-stop battery connection status detection method of the present invention requires no additional hardware equipment or modification of the vehicle wiring harness. The overall solution is based on a pure software algorithm, which avoids the impact of adding hardware on the feasibility of the detection method and improves the adaptability of the vehicle start-stop battery connection status detection method of the present invention.

[0063] The vehicle start-stop battery connection status detection method of the present invention also includes an early warning mechanism. By measuring the increase of a first feature relative to a first feature benchmark value, a graded early warning is given for mechanical loosening faults. This method of giving early warnings by characterizing the indicative features of sudden mechanical loosening allows sudden mechanical loosening to be noticed by staff as early as possible, providing early warnings within a controllable range, and prompting immediate repairs when necessary. This approach can balance the continuity and safety of daily vehicle operation, further improving the reliability of the vehicle start-stop battery connection status detection method. Attached Figure Description

[0064] Figure 1 This is a schematic flowchart of a vehicle start-stop battery connection status detection method according to Embodiment 1 of the present invention. Detailed Implementation

[0065] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments and specific features in the embodiments are detailed descriptions of the technical solution of the present application, rather than limitations thereof. In the absence of conflict, the embodiments and technical features in the embodiments can be combined with each other.

[0066] In this article, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0067] Example 1:

[0068] This embodiment describes a method for detecting the connection status of a vehicle start-stop battery, such as... Figure 1 As shown, it includes:

[0069] S1: Collect voltage and current data before and after startup, as well as timing data of voltage, current and temperature within the preset startup duration;

[0070] S2: Based on the collected data, calculate four start-stop battery connection status detection features; the first feature represents the conduction performance of the start-stop battery connection at the maximum current during the start-up period; the second feature represents the overall situation of the external connection resistance during the start-up period; the third feature represents the basic conduction performance of the start-stop battery connection after start-up; the fourth feature represents the polarization characteristics of the start-stop battery itself.

[0071] S3: Determine the vehicle start-stop battery connection status based on the start-stop battery connection status detection characteristics; the determination of the vehicle start-stop battery connection status includes: determining whether a mechanical loosening fault has occurred; determining whether a corrosion aging fault has occurred.

[0072] In step S1, the voltage and current data before and after startup include: the static stable open-circuit voltage of the start-stop battery and the initial static current of the main power supply circuit measured before startup, and the steady-state voltage across the start-stop battery and the steady-state current of the main power supply circuit measured after startup.

[0073] The timing data of voltage, current, and temperature include: the voltage across the start-up and stop batteries, the current in the main power supply circuit, and the corresponding start-up and stop battery temperature at various times during the current startup process.

[0074] Step S2 includes:

[0075] Based on the timing data of voltage, current and temperature within the preset startup time, calculate the total internal resistance of the main power supply circuit at each moment during the current startup process;

[0076] Calculate the external connection resistance at each time step based on the total internal resistance of the main power supply circuit at each time step.

[0077] Based on the external connection resistance within the preset startup time, calculate the corresponding first feature and second feature; the first feature is the peak connection resistance, and the second feature is the average external connection resistance.

[0078] The specific calculation process for the first and second features is as follows:

[0079] Calculation of the total internal resistance of the main power supply circuit at various times:

[0080] During each vehicle start-up process, the real-time total internal resistance of the main power supply circuit is calculated based on the real-time voltage changes of the start-stop battery and the real-time current changes of the main power supply circuit. The total internal resistance R of the main power supply circuit at time t is then calculated. total The formula for calculating (t) is as follows:

[0081] R total (t)=ΔU(t) / ΔI(t),

[0082] In the formula, ΔU(t) represents the voltage change of the battery at time t when it is turned on and off; ΔU(t) = U ocv -U(t), U ocv To stabilize the open-circuit voltage of the start-stop battery during rest, U ocv Specifically, before each startup, when the main power supply circuit is disconnected, there is no load current, and the battery has been fully rested to reach electrochemical steady state, the open-circuit voltage across the start-up and shutdown battery is U(t), where U(t) is the voltage across the start-up and shutdown battery at time t; ΔI(t) is the change in current in the main power supply circuit at time t, ΔI(t) = I(t) - I ocv The initial static current I of the main power supply circuit ocv I(t) is 0, where I(t) is the current in the main power supply circuit at time t; t is the time sequence number within the preset start-up duration.

[0083] The vehicle start-up time is preset, specifically referring to the time from when the main power supply circuit is turned on (as measured at the factory) and the vehicle begins to start, until the voltage across the start-stop battery recovers to 95% of its pre-start stable open-circuit voltage. The start-up time varies for different vehicle models, ranging from 3 to 15 seconds. For the same vehicle model, the start-up time is the same fixed value. In this embodiment, the start-up time for heavy-duty trucks is 15 seconds. With a step size of 100ms, the current in the main power supply circuit and the voltage across the start-stop battery are collected at various moments within the 15-second start-up time.

[0084] Calculation of the maximum total internal resistance of the main power supply circuit during each startup:

[0085] The maximum total internal resistance R of the main power supply circuit during each startup peak This represents the maximum total internal resistance of the main power supply circuit at all times within the corresponding startup duration.

[0086] The internal resistance of the start / stop battery is separated from the total internal resistance of the main power supply circuit, and the external connection resistance is obtained in real time:

[0087] The corresponding external connection resistance is obtained by subtracting the corresponding internal resistance of the start / stop battery from the total internal resistance of the main power supply circuit; the external connection resistance R at time t is... connection The formula for calculating (t) is:

[0088] R connection (t)=R total (t)-R cell (t),

[0089] In the formula, R total (t) represents the total internal resistance of the main power supply circuit at time t; R cell R(t) is the internal resistance of the start-stop battery at time t. Based on the current in the main power supply circuit at time t and the temperature of the start-stop battery, R is obtained by consulting a pre-obtained mapping table of the internal resistance of the start-stop battery. cell (t); R cell (t) The specific acquisition process is as follows: The real-time battery internal resistance is obtained by retrieving the start-stop battery internal resistance MAP table stored on-board and calibrated based on temperature and current conditions, matching the real-time temperature and current conditions. The start-stop battery internal resistance MAP table is a mapping table of the start-stop battery internal resistance;

[0090] In this embodiment, the mapping table of the internal resistance of the 30Ah start-stop battery stored on-board is as follows:

[0091] Table 1. Mapping table of internal resistance of 30Ah start-stop battery for vehicle storage

[0092]

[0093] The start-stop battery resistance not shown in the table is obtained directly using linear interpolation. In this embodiment, R cell (t) is obtained by looking up the mapping table of the internal resistance of the start-stop battery shown in Table 1 based on the current of the main power supply circuit and the temperature of the start-stop battery at time t.

[0094] Calculation of the first feature:

[0095] Peak connection resistance R at each startup peak_connection The calculation formula is:

[0096] R peak_connection =R peak -R cell (I peak ,T peak ),

[0097] In the formula, R peak R is the peak total internal resistance of the main power supply circuit for each startup. cell (I peak ,T peak The maximum current I in the main power supply circuit during each startup is...peak The corresponding internal resistance of the start-stop battery, T peak The maximum current I in the main power supply circuit during each startup. peak The recorded start-stop battery temperature, R cell (I peak ,T peak ) through I peak and T peak According to the table, peak connection resistance characterizes the conductivity at the start-stop battery connection point during the startup period when the current is at its maximum. Peak connection resistance is a key characteristic indicating sudden mechanical loosening.

[0098] Calculation of the second feature:

[0099] The average value R of the external connection resistance is obtained by averaging the values ​​of the external connection resistance at all times within the preset startup duration. aver_connection The average value of the external connection resistance is used to characterize the overall situation of the external connection resistance during the startup period.

[0100] Step S2 also includes:

[0101] Based on the voltage and current data before and after startup, the third and fourth characteristics are calculated; the third characteristic is the steady-state connection resistance, and the fourth characteristic is the voltage recovery time.

[0102] Calculation of the third feature:

[0103] Steady-state connection resistor R at each startup con_static The calculation formula is:

[0104] R con_static =(U ocv -U load ) / I load ,

[0105] In the formula, U ocv The static stable open-circuit voltage of the start-stop battery; U load To start and stop the steady-state voltage across the battery, U load Specifically, this refers to the voltage across the start / stop battery when the main power supply circuit is in a stable conduction phase after the vehicle starts; I load I is the steady-state current of the main power supply circuit. load Specifically, it refers to the current in the main power supply circuit when the main power supply circuit is in a stable conduction phase after the vehicle starts;

[0106] The third characteristic characterizes the basic conductivity at the start-stop battery connection after startup.

[0107] Calculation of the fourth feature:

[0108] The voltage recovery time for each startup is: the time T required for the voltage across the start-stop battery to recover to the steady-state voltage of the start-stop battery at the end of the preset startup duration. recovery The fourth characteristic characterizes the polarization properties of the start-stop battery itself.

[0109] Step S3 includes:

[0110] If the number of times the increase in the average value of peak connection resistance, steady-state connection resistance and external connection resistance exceeds the preset short-term increase threshold reaches the preset number threshold, and the voltage recovery time is less than the preset voltage recovery time threshold, then a mechanical loosening fault is determined to have occurred.

[0111] The increase in the average values ​​of peak connection resistance, steady-state connection resistance, and external connection resistance being greater than a preset short-term increase threshold means that:

[0112] The peak connection resistance is compared with the reference peak connection resistance, the steady-state connection resistance is compared with the reference steady-state connection resistance, and the average external connection resistance is compared with the average external connection resistance. The reference peak connection resistance, reference steady-state connection resistance, and average external connection resistance are measured according to the vehicle's factory calibration or after the most recent standardized maintenance.

[0113] Alternatively, compare the current peak connection resistance with the previous peak connection resistance, compare the current steady-state connection resistance with the previous steady-state connection resistance, and compare the average external connection resistance of the current external connection resistance with the average external connection resistance of the previous external connection resistance.

[0114] If, within the preset total cycle, the average value of the peak connection resistance, steady-state connection resistance, and external connection resistance measured in each sub-cycle is greater than the increase in the average value of the peak connection resistance, steady-state connection resistance, and external connection resistance measured in the previous sub-cycle, compared to the increase in the average value of the peak connection resistance, steady-state connection resistance, and external connection resistance measured in the previous sub-cycle, exceeds the preset long-term increase threshold, and the voltage recovery time of the last startup within the preset total cycle is greater than or equal to the preset voltage recovery time threshold, then a corrosion aging fault is determined to have occurred.

[0115] 1) Identification of sudden mechanical loosening faults:

[0116] When the battery terminals and wiring nuts become mechanically loose due to vehicle bumps and vibrations, it only causes the overall external connection resistance to rise synchronously during the start-up period. The trend of external connection resistance change during the same start-up does not change significantly and does not affect the polarization characteristics of the start-stop battery itself. Therefore, compared with before the mechanical loosening, the peak connection resistance and steady-state connection resistance will suddenly increase after the mechanical loosening, and the average value of the external connection resistance will also suddenly increase, but the voltage recovery time will not change significantly.

[0117] 2) Identification of long-term corrosion and aging faults:

[0118] When electrochemical oxidation or long-term creep aging of the metal material occurs at the connection surface between the start-stop battery and the main power supply circuit, affecting the polarity characteristics of the start-stop battery, the peak connection resistance and steady-state connection resistance show a continuous and slow increasing trend, the average value of the external connection resistance also shows a corresponding slow increasing trend, and the voltage recovery time is prolonged.

[0119] In one specific embodiment, the process of determining a mechanical loosening fault based on the start-stop battery connection status detection characteristics is as follows:

[0120] If the peak value of the connection resistor R is more than 2 out of the last 5 start-stop cycles, peak_connection Steady-state connection resistor R con_static and the average value of external connection resistance R aver_connection If the voltage increase is greater than 30% and the voltage recovery time is less than the preset voltage recovery time threshold, then a mechanical loosening fault is determined to have occurred.

[0121] Peak connection resistance R peak_connection Steady-state connection resistor R con_static and the average value of external connection resistance R aver_connection An increase of more than 30% means:

[0122] The peak connection resistance is greater than 1.3 times the reference peak connection resistance, the steady-state connection resistance is greater than 1.3 times the reference steady-state connection resistance, and the average external connection resistance is greater than 1.3 times the average external connection resistance.

[0123] Alternatively, the peak connection resistance of the current startup is greater than 1.3 times the peak connection resistance of the previous startup, the steady-state connection resistance of the current startup is greater than 1.3 times the steady-state connection resistance of the previous startup, and the average external connection resistance of the current startup is greater than 1.3 times the average external connection resistance of the previous startup.

[0124] In one specific embodiment, the preset voltage recovery time threshold is 0.5s.

[0125] In one specific embodiment, the process of determining corrosion aging faults based on the start-stop battery connection status detection characteristics is as follows:

[0126] If the peak connection resistance R is measured weekly over a consecutive month... peak_connection Steady-state connection resistor R con_static and the average value of external connection resistance R aver_connection The weekly average value compared to the peak connection resistance R measured last week peak_connection Steady-state connection resistor R con_static and the average value of external connection resistance R aver_connection If the weekly average increase is greater than 1% and the voltage recovery time is greater than or equal to the preset voltage recovery time threshold, then a progressive terminal aging fault is determined to have occurred.

[0127] Peak connection resistance R measured weekly peak_connection Steady-state connection resistor R con_static and the average value of external connection resistance R aver_connection The weekly average values ​​refer to the peak connection resistance R measured each week. peak_connection Steady-state connection resistor R con_static and the average value of external connection resistance R aver_connection Divide by the number of times it was launched within the corresponding week.

[0128] The vehicle start-stop battery connection status detection method of this embodiment further includes:

[0129] Step S4: Based on the first feature and the pre-set early warning mechanism, output the corresponding early warning information; the pre-set early warning mechanism includes:

[0130] The warning levels are divided into three levels based on the increase of the first feature relative to the first feature benchmark value; the first feature benchmark value is obtained based on the vehicle's factory calibration or after the most recent standardized maintenance.

[0131] The first-level warning is: when the increase of the first feature relative to the first feature baseline value is within the first range, a fault prompt is output;

[0132] The level 2 warning is as follows: when the increase of the first feature relative to the first feature benchmark value falls within the second range, an appropriate maintenance reminder will be output.

[0133] The Level 3 warning is as follows: when the increase of the first feature relative to the first feature benchmark value falls within the third range, an immediate repair prompt is output.

[0134] In one specific embodiment, the pre-set early warning mechanism is as follows:

[0135] The first-level warning is as follows: when the increase in peak connection resistance compared to the reference peak connection resistance is greater than or equal to 15% and less than 30%, it is considered a minor abnormality and a fault message will be output; the reference peak connection resistance is the peak connection resistance measured according to the vehicle's factory calibration or the most recent standardized maintenance.

[0136] The level 2 warning is as follows: when the increase in peak connection resistance compared to the reference peak connection resistance is greater than or equal to 30% and less than 50%, it is considered a moderate anomaly, and a maintenance reminder will be output as appropriate.

[0137] The Level 3 warning is as follows: when the increase in peak connection resistance compared to the reference peak connection resistance is greater than or equal to 50%, it is considered a severe abnormality, and an immediate repair prompt will be output.

[0138] Example 2:

[0139] Based on the same inventive concept as Embodiment 1, this embodiment introduces a vehicle start-stop battery connection status detection system, which reuses the vehicle's original hardware equipment, including voltage sensors, current sensors, temperature sensors, on-board computing units, and vehicle controllers.

[0140] The vehicle start-stop battery connection status detection system includes:

[0141] The voltage sensor and the current sensor are used to collect voltage and current data before and after startup, as well as timing data of voltage and current within a preset startup duration, respectively.

[0142] The temperature sensor is used to collect time-series temperature data within a preset start-up time.

[0143] The on-board computing unit is used to calculate four start-stop battery connection status detection features based on the collected data; the first feature represents the conductivity of the start-stop battery connection at the maximum current during the start-up period; the second feature represents the overall situation of the external connection resistance during the start-up period; the third feature represents the basic conductivity of the start-stop battery connection after start-up; and the fourth feature represents the polarization characteristics of the start-stop battery itself.

[0144] The vehicle controller is used to determine the connection status of the vehicle start-stop battery based on the detection characteristics of the start-stop battery connection status; the determination of the connection status of the vehicle start-stop battery includes: determining whether a mechanical loosening fault has occurred; determining whether a corrosion aging fault has occurred.

[0145] The vehicle controller is further configured to output corresponding warning information based on the first feature and a pre-set warning mechanism; the pre-set warning mechanism includes:

[0146] The warning levels are divided into three levels based on the increase of the first feature relative to the first feature benchmark value; the first feature benchmark value is obtained based on the vehicle's factory calibration or after the most recent standardized maintenance.

[0147] The first-level warning is: when the increase of the first feature relative to the first feature baseline value is within the first range, a fault prompt is output;

[0148] The level 2 warning is as follows: when the increase of the first feature relative to the first feature benchmark value falls within the second range, an appropriate maintenance reminder will be output.

[0149] The Level 3 warning is as follows: when the increase of the first feature relative to the first feature benchmark value falls within the third range, an immediate repair prompt is output.

[0150] 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 embodied 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.

[0151] 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.

[0152] 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.

[0153] 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.

[0154] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for detecting the connection status of a vehicle start-stop battery, characterized in that, include: Collect voltage and current data before and after startup, as well as time-series data of voltage, current and temperature within a preset startup duration; Based on the collected data, calculate four start-stop battery connection status detection features; The first characteristic characterizes the conductivity at the start-stop battery connection during the startup duration when the current is at its maximum. The second feature characterizes the overall situation of the external connection resistance during the startup period; The third characteristic characterizes the basic conductivity of the start-stop battery connection after startup; The fourth characteristic characterizes the polarization properties of the start-stop battery itself; The start-stop battery connection status of the vehicle is determined based on the start-stop battery connection status detection characteristics. The determination of the vehicle start-stop battery connection status includes: determining whether a mechanical loosening fault has occurred; Determine whether corrosion or aging has occurred.

2. The vehicle start-stop battery connection status detection method according to claim 1, characterized in that, The voltage and current data before and after startup include: the static stable open-circuit voltage of the start-stop battery and the initial static current of the main power supply circuit measured before startup, and the steady-state voltage across the start-stop battery and the steady-state current of the main power supply circuit measured after startup. The timing data of voltage, current, and temperature include: the voltage across the start-up and stop batteries, the current in the main power supply circuit, and the corresponding start-up and stop battery temperature at various times during the current startup process.

3. The vehicle start-stop battery connection status detection method according to claim 2, characterized in that, Based on the collected data, calculate the first feature and the second feature, including: Based on the timing data of voltage, current and temperature within the preset startup time, calculate the total internal resistance of the main power supply circuit at each moment during the current startup process; Calculate the external connection resistance at each time step based on the total internal resistance of the main power supply circuit at each time step. Based on the external connection resistance within the preset startup time, calculate the corresponding first feature and second feature; the first feature is the peak connection resistance, and the second feature is the average external connection resistance. Peak connection resistance R at each startup peak_connection The calculation formula is: R peak_connection =R peak -R cell (I peak ,T peak ), In the formula, R peak R is the maximum total internal resistance of the main power supply circuit for each startup. cell (I peak ,T peak The maximum current I in the main power supply circuit during each startup is... peak The corresponding internal resistance of the start-stop battery, T peak The maximum current I in the main power supply circuit during each startup. peak The recorded start-stop battery temperature, R cell (I peak ,T peak ) through I peak and T peak The mapping table of the internal resistance of the start-stop battery body is obtained by querying the pre-acquired mapping table; Average external connection resistance R during each startup aver_connection This is the average value of the external connection resistance at all times within the preset startup duration.

4. The vehicle start-stop battery connection status detection method according to claim 3, characterized in that, The external connection resistor R at time t connection The formula for calculating (t) is: R connection (t)=R total (t)-R cell (t), In the formula, R total (t) represents the total internal resistance of the main power supply circuit at time t; R cell R(t) is the internal resistance of the start-stop battery at time t. Based on the current in the main power supply circuit at time t and the temperature of the start-stop battery, R is obtained by consulting a pre-obtained mapping table of the internal resistance of the start-stop battery. cell (t); t is the time sequence number within the preset startup duration; The total internal resistance R of the main power supply circuit at time t total The formula for calculating (t) is as follows: R total (t)=ΔU(t) / ΔI(t), In the formula, ΔU(t) represents the voltage change of the battery at time t when it is turned on and off; ΔU(t) = U ocv -U(t), U ocv Let U(t) be the static stable open-circuit voltage of the start-stop battery, and let U(t) be the voltage across the start-stop battery at time t; let ΔI(t) be the change in current in the main power supply circuit at time t, and let ΔI(t) = I(t) - I ocv The initial static current I of the main power supply circuit ocv I(t) is 0, and I(t) is the current in the main power supply circuit at time t.

5. The vehicle start-stop battery connection status detection method according to claim 3, characterized in that, Based on the collected data, the third and fourth features are calculated, including: Based on the voltage and current data before and after startup, the third and fourth characteristics are calculated; the third characteristic is the steady-state connection resistance, and the fourth characteristic is the voltage recovery time. Steady-state connection resistor R at each startup con_static The calculation formula is: R con_static =(U ocv -U load ) / I load , In the formula, U ocv The static stable open-circuit voltage of the start-stop battery; U load This refers to the steady-state voltage across the battery terminals for starting and stopping; I load This refers to the steady-state current of the main power supply circuit. The voltage recovery time for each startup is the time required for the voltage across the start-stop battery to recover to the steady-state voltage of the start-stop battery at the end of the preset startup duration.

6. The vehicle start-stop battery connection status detection method according to claim 5, characterized in that, The step of determining the vehicle start-stop battery connection status based on the start-stop battery connection status detection characteristics includes: If the number of times the increase in the average value of peak connection resistance, steady-state connection resistance and external connection resistance exceeds the preset short-term increase threshold reaches the preset number threshold, and the voltage recovery time is less than the preset voltage recovery time threshold, then a mechanical loosening fault is determined to have occurred. If, within the preset total cycle, the average value of the peak connection resistance, steady-state connection resistance, and external connection resistance measured in each sub-cycle is greater than the increase in the average value of the peak connection resistance, steady-state connection resistance, and external connection resistance measured in the previous sub-cycle, compared to the increase in the average value of the peak connection resistance, steady-state connection resistance, and external connection resistance measured in the previous sub-cycle, exceeds the preset long-term increase threshold, and the voltage recovery time of the last startup within the preset total cycle is greater than or equal to the preset voltage recovery time threshold, then a corrosion aging fault is determined to have occurred.

7. The vehicle start-stop battery connection status detection method according to claim 6, characterized in that, The increase in the average values ​​of peak connection resistance, steady-state connection resistance, and external connection resistance being greater than a preset short-term increase threshold means that: Compare the peak connection resistance with the reference peak connection resistance, compare the steady-state connection resistance with the reference steady-state connection resistance, and compare the average external connection resistance with the average external connection resistance. The average values ​​of the reference peak connection resistance, the reference steady-state connection resistance, and the reference external connection resistance are obtained based on the vehicle's factory calibration or after the most recent standardized maintenance. Alternatively, compare the current peak connection resistance with the previous peak connection resistance, compare the current steady-state connection resistance with the previous steady-state connection resistance, and compare the average external connection resistance of the current external connection resistance with the average external connection resistance of the previous external connection resistance.

8. The vehicle start-stop battery connection status detection method according to claim 1, characterized in that, Also includes: Based on the first feature and the pre-set early warning mechanism, output the corresponding early warning information; The pre-set early warning mechanism includes: The warning levels are divided into three levels based on the increase of the first feature relative to the first feature benchmark value; the first feature benchmark value is obtained based on the vehicle's factory calibration or after the most recent standardized maintenance. The first-level warning is: when the increase of the first feature relative to the first feature baseline value is within the first range, a fault prompt is output; The level 2 warning is as follows: when the increase of the first feature relative to the first feature benchmark value falls within the second range, an appropriate maintenance reminder will be output. The Level 3 warning is as follows: when the increase of the first feature relative to the first feature benchmark value falls within the third range, an immediate repair prompt is output.

9. A vehicle start-stop battery connection status detection system, comprising a voltage sensor, a current sensor, a temperature sensor, an on-board computing unit, and a vehicle controller, characterized in that, The voltage sensor and the current sensor are used to collect voltage and current data before and after startup, as well as timing data of voltage and current within a preset startup duration, respectively. The temperature sensor is used to collect time-series temperature data within a preset start-up time. The on-board computing unit is used to calculate four start-stop battery connection status detection features based on the collected data. The first characteristic characterizes the conductivity at the start-stop battery connection during the startup duration when the current is at its maximum. The second feature characterizes the overall situation of the external connection resistance during the startup period; The third characteristic characterizes the basic conductivity of the start-stop battery connection after startup; The fourth characteristic characterizes the polarization properties of the start-stop battery itself; The vehicle controller is used to determine the connection status of the vehicle's start-stop battery based on the start-stop battery connection status detection characteristics. The determination of the vehicle start-stop battery connection status includes: determining whether a mechanical loosening fault has occurred; Determine whether corrosion or aging has occurred.

10. The vehicle start-stop battery connection status detection system according to claim 9, characterized in that, The vehicle controller is further configured to output corresponding warning information based on the first feature and a pre-set warning mechanism; the pre-set warning mechanism includes: The warning levels are divided into three levels based on the increase of the first feature relative to the first feature benchmark value; the first feature benchmark value is obtained based on the vehicle's factory calibration or after the most recent standardized maintenance. The first-level warning is: when the increase of the first feature relative to the first feature baseline value is within the first range, a fault prompt is output; The level 2 warning is as follows: when the increase of the first feature relative to the first feature benchmark value falls within the second range, an appropriate maintenance reminder will be output. The Level 3 warning is as follows: when the increase of the first feature relative to the first feature benchmark value falls within the third range, an immediate repair prompt is output.

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