Discharge amount estimation system for a battery

Abstract

Provided is a battery discharge amount estimation system capable of suppressing estimation of a battery discharge amount that is significantly different from an actual battery discharge amount. A battery discharge amount estimation system mounted on a vehicle includes: an acquisition unit that acquires a vehicle parked time of the vehicle and an average dark current value that is an average value of a current flowing from a battery during the vehicle parked time; a determination unit that determines whether the average dark current value exceeds a warning value set in accordance with the vehicle parked time; and an estimation unit that estimates a battery discharge amount using the warning value instead of the average dark current value in a case where the average dark current value exceeds the warning value.

Description

Technical Field

[0001] This invention relates to a system for estimating the discharge capacity of a battery installed in a vehicle. Background Technology

[0002] Patent Document 1 discloses a system for estimating the amount of battery discharge during vehicle parking based on the vehicle parking time and the average value of the current flowing from the battery to the vehicle load (dark current) during the vehicle parking period.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2018-146416 Summary of the Invention For example, when the battery discharge is estimated via a central server connected wirelessly to the vehicle, a synchronization deviation may occur between the average dark current value and the vehicle's parking time due to delays in transmitting data (vehicle parking time, average dark current value) from the vehicle to the central server or delays in server processing within the central server. This synchronization deviation between the average dark current value and the vehicle's parking time can occur even when the discharge is estimated inside the vehicle.

[0004] Therefore, when estimating the battery discharge using the average dark current value (which has synchronization deviation) and the vehicle's parking time, the estimated result may differ significantly from the actual battery discharge. Thus, further research is needed on methods for estimating battery discharge.

[0005] The present invention was made in view of the above-mentioned problems, and its object is to provide a battery discharge estimation system that can suppress the estimation of battery discharge amount that is significantly different from the actual battery discharge amount.

[0006] To address the aforementioned issues, one aspect of the present invention is a battery discharge estimation system mounted on a vehicle. The battery discharge estimation system comprises: an acquisition unit that acquires the vehicle's parking time and the average value of the current flowing from the battery during the parking period, i.e., an average dark current value; a determination unit that determines whether the average dark current value exceeds a warning value set based on the vehicle parking time; and an estimation unit that, if the average dark current value exceeds the warning value, uses the warning value instead of the average dark current value to estimate the battery discharge.

[0007] Invention Effects The battery discharge estimation system according to the present invention can suppress the estimation of battery discharge that is significantly different from the actual battery discharge. Attached Figure Description

[0008] Figure 1 This is a schematic structural diagram of a discharge quantity estimation system according to an embodiment of the present invention.

[0009] Figure 2 This is a flowchart of the battery discharge estimation control process executed by the discharge estimation system.

[0010] Figure 3 This is a diagram illustrating an example of a mapping that derives the average dark current warning value.

[0011] Figure 4 This is a schematic diagram of the region where the average dark current value is protected. Detailed Implementation

[0012] In the case of estimating the discharge amount of the vehicle battery in the battery discharge amount estimation system of the present invention, in order to prevent the average dark current value of the vehicle from deviating from the synchronization of the vehicle's parking time, a warning process is set for the average dark current value.

[0013] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0014] <Implementation Method> [structure] Figure 1 This is a block diagram illustrating the schematic structure of a vehicle communication system 100 including a discharge quantity estimation system 121 according to an embodiment of the present invention. Figure 1 The vehicle communication system 100 illustrated in the diagram includes a vehicle 110 and a central server 120 in its structure.

[0015] (1) Vehicle Vehicle 110 is communicatively connected to central server 120. This vehicle 110, such as a car, includes at least a battery 111, a data acquisition unit 112, and a data transmission unit 113. Furthermore, in Figure 1 The example shown is a single vehicle 110 that can be communicatively connected to the central server 120, but it is also possible for multiple vehicles 110 to be communicatively connected to the central server 120 respectively.

[0016] In order to reduce power consumption while the vehicle is parked, the vehicle 110 can switch between a wake-up state where all functions are activated and a sleep state where some functions are deactivated at a specified time.

[0017] Battery 111 is a rechargeable battery, such as a lithium-ion battery or a lead-acid battery. An auxiliary battery can be exemplified as battery 111. This battery 111 can be charged by a generator (not shown) such as an alternator, and can supply (discharge) the electricity it stores to accessories or equipment (not shown) mounted on vehicle 110.

[0018] The data acquisition unit 112 is a structure for acquiring vehicle data at predetermined intervals or irregularly. This vehicle data includes information related to the parking of the vehicle 110 and information related to the battery 111. As information related to the parking of the vehicle 110, the vehicle parking time (the ignition-off time of the vehicle 110) can be displayed. As information related to the battery 111, the average value of the dark current flowing from the battery 111 to a load (not shown) mounted on the vehicle 110 (hereinafter referred to as the "average dark current value") can be displayed. This dark current is, for example, the current consumed by functions related to electronic key authentication or by a dashcam recording video while the vehicle is parked. The dark current is acquired using a current sensor (not shown) installed on the battery 111.

[0019] The average dark current value can be calculated using multiple dark current values ​​measured at each moment when a specific device or equipment in the vehicle 110 is in a wake-up state, according to the following formula 1.

[0020] Average dark current value = total measured dark current values ​​ / number of measurements ... (Equation 1) The data transmission unit 113 is a structure that controls the communication between the vehicle 110 and the central server 120. The data transmission unit 113 transmits the vehicle data acquired by the data acquisition unit 112 to the central server 120. This data transmission unit 113 is implemented, for example, through a data communication module (DCM).

[0021] (2) Central server The central server 120 is communicatively connected to the vehicle 110. The central server 120 may be, for example, a server in the cloud, and at least includes a discharge estimation system 121 and a notification unit 125.

[0022] The discharge estimation system 121 is a system for estimating the discharge amount of the battery 111 mounted on the vehicle 110. The discharge estimation system 121 includes a data receiving unit 122, a warning processing and determination unit 123, and a discharge estimation unit 124.

[0023] The data receiving unit 122 is a structure that enables communication between the control center server 120 and the vehicle 110. This data receiving unit 122 is capable of receiving vehicle data sent from the vehicle 110 and obtaining the vehicle parking time and average dark current value contained in the vehicle data.

[0024] The warning processing determination unit 123 is a structure used to determine whether the average dark current value acquired by the data receiving unit 122 exceeds a warning value (hereinafter referred to as the "average dark current warning value") set according to the vehicle parking time. This average dark current warning value is, for example, as shown in the example... Figure 3 As shown, it is pre-assigned in the form of a mapping.

[0025] exist Figure 3 In the example, the average dark current warning value is set as "-1.0A (Amperes)" when the vehicle 110 is parked for less than 1 hour (1H), "-0.5A" when the vehicle is parked for more than 1 hour but less than 2 hours (2H), "-0.3A" when the vehicle is parked for more than 2 hours but less than 4 hours (4H), "-0.2A" when the vehicle is parked for more than 4 hours but less than 10 hours (10H), and "-0.1A" when the vehicle is parked for more than 10 hours (10H). Furthermore, in this... Figure 3 In the example, the inflow and outflow currents of battery 111 are expressed as follows: the current flowing into battery 111 for charging is positive (positive), and the current flowing out of battery 111 for discharging is negative (negative).

[0026] The discharge estimation unit 124 is a structure used to estimate the discharge amount of the battery 111. Specifically, the discharge estimation unit 124 appropriately controls the dark current value used for estimating the discharge amount of the battery 111 based on the result determined by the warning processing determination unit 123. The processing performed by the discharge estimation unit 124 will be described later.

[0027] The notification unit 125 performs an appropriate notification based on the discharge amount of the battery 111 estimated by the discharge amount estimation unit 124. This notification is preferably made when the battery 111 is in a state of temporary over-discharge (voltage drop) or when the battery 111 is in a state of degradation. Examples of notification destinations include the vehicle 110, the user of the vehicle 110, or a mobile terminal of the driver.

[0028] [control] Next, refer to Figure 2 The control performed by the discharge quantity estimation system 121 according to this embodiment will be explained. Figure 2 This is a flowchart illustrating the processing sequence of the discharge quantity estimation control of battery 111 performed by each structure of the discharge quantity estimation system 121. Figure 2 The discharge estimation control of the battery 111 shown can be initiated, for example, by sending vehicle data from the vehicle 110 to the central server 120 at the moment when the ignition is turned on.

[0029] (Step S201) The data receiving unit 122 of the discharge estimation system 121 obtains the vehicle parking time and average dark current value from the vehicle data received from the vehicle 110. If the vehicle parking time and average dark current value are obtained by the data receiving unit 122, the process proceeds to step S202.

[0030] (Step S202) The warning processing and determination unit 123 of the discharge estimation system 121 derives an average dark current warning value corresponding to the vehicle parking time obtained in step S201 above. As an example, this average dark current warning value can be obtained from a mapping (not shown) pre-stored in a storage unit or the like. Figure 3 The average dark current warning value corresponding to the vehicle parking time is extracted and exported. If the warning processing determination unit 123 exports the average dark current warning value, the processing proceeds to step S203.

[0031] (Step S203) The warning processing determination unit 123 of the discharge estimation system 121 determines whether the average dark current value obtained in step S201 exceeds the average dark current warning value derived in step S202. This determination is performed to confirm whether there is a synchronization deviation between the average dark current value and the vehicle parking time. If the warning processing determination unit 123 determines that the average dark current value exceeds the average dark current warning value (step S203, Yes), the process proceeds to step S204. On the other hand, if the warning processing determination unit 123 determines that the average dark current value does not exceed the average dark current warning value (step S203, No), the process proceeds to step S205.

[0032] (Step S204) The discharge estimation unit 124 of the discharge estimation system 121 uses the average dark current value obtained in step S201 above to estimate the discharge amount of the battery 111. Known methods can be used in estimating the discharge amount of the battery 111. Once the discharge amount of the battery 111 is estimated by the discharge estimation unit 124, the control process ends.

[0033] (Step S205) The discharge estimation unit 124 of the discharge estimation system 121 uses the average dark current warning value derived in step S203 above to estimate the discharge amount of the battery 111. That is, the discharge estimation system 121 uses the average dark current value obtained from the vehicle 110 instead of the average dark current warning value derived by the discharge estimation system 121 to estimate the discharge amount of the battery 111.

[0034] By switching to this average dark current warning value, the average dark current value used to estimate the discharge amount of battery 111 is suppressed to [a certain value]. Figure 4 The shaded area is shown. Therefore, even when the central server 120 performs estimation processing using an average dark current value that deviates from the synchronization of the vehicle's parking time, the average dark current value is limited (or increased) by the warning processing, thus preventing the discharge estimation unit 124 from estimating a discharge amount that is significantly different from the actual discharge amount of the battery 111. If the discharge amount of the battery 111 is estimated by the discharge estimation unit 124, this control ends.

[0035] In addition, after the processing of step S204 or step S205, an appropriate notification may be made based on the notification unit 125.

[0036] <Function / Effect> As described above, the discharge estimation system 121 according to an embodiment of the present invention acquires the average value of the vehicle parking time of the vehicle 110 and the average value of the current flowing from the battery 111 during the vehicle parking period, i.e., the average dark current value. If the average dark current value does not exceed the average dark current warning value set according to the vehicle parking time, the discharge amount of the battery 111 is estimated using the average dark current value. If the average dark current value exceeds the average dark current warning value, the discharge amount of the battery 111 is estimated using the average dark current warning value.

[0037] By using the warning processing of the average dark current value, the average dark current value used for discharge estimation is limited (or increased), thus preventing the discharge estimation system 121 from estimating a discharge amount that is significantly different from the actual discharge amount of the battery 111.

[0038] The discharge estimation system of the present invention can be used to estimate the discharge amount of a battery installed in a vehicle, etc.

[0039] Symbol Explanation 100 - Vehicle communication system, 110 - Vehicle, 111 - Battery, 112 - Data acquisition unit, 113 - Data transmission unit, 120 - Central server, 121 - Discharge estimation system, 122 - Data receiving unit, 123 - Warning processing and judgment unit, 124 - Discharge estimation unit, 125 - Notification unit.

Claims

1. A battery discharge estimation system, mounted on a vehicle, characterized in that it comprises: The acquisition unit acquires the vehicle's parking time and the average value of the current flowing from the battery during the vehicle's parking period, i.e., the average dark current value. The determination unit determines whether the average dark current value exceeds a warning value set based on the vehicle parking time. and The estimation unit estimates the discharge amount of the battery by using the warning value instead of the average dark current value when the average dark current value exceeds the warning value.

2. The battery discharge estimation system according to claim 1, characterized in that, The acquisition unit, the determination unit, and the estimation unit are located on a central server that is wirelessly connected to the vehicle.

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