Electricity meter of light electric vehicle

Abstract

The utility model discloses a voltameter of a light electric vehicle, which comprises a B + input end, a B-output end and a P-end, a voltage sampling circuit is arranged between the B + input end and the B-output end, a voltameter IC is connected in series with one side of the voltage sampling circuit, a current sampling resistor is connected in series between the B-output end and the P-end, and the current sampling resistor is connected in series with the voltage sampling circuit. And the B + input end is connected in series with a Bluetooth MCU. According to the utility model, an electric quantity calculation and battery health degree scheme combining coulomb calculation and dynamic internal resistance measurement is adopted, the accuracy of electric quantity calculation is improved, an LIN bus interface standard is adopted, and a Bluetooth BLE wireless connection function is added, so that a whole vehicle system can be conveniently docked with data, and information can be obtained even if wired connection is not provided.

Description

Technical Field

[0001] The utility model relates to the technical field of electric vehicle electricity meters, in particular to an electricity meter for a light electric vehicle. Background Art

[0002] Light electric vehicles utilize a large number of lead-acid batteries and lithium batteries without data interfaces. For these scenarios, the meters on two-wheeled vehicles display and calculate the battery level and remaining mileage using voltage measurements, but this method is very inaccurate. As the number of battery cycles increases, the internal resistance gradually increases. Therefore, when the vehicle accelerates or requires high power output when riding uphill, the battery voltage drops due to internal resistance. At this time, the battery level measured using the voltage method will also drop sharply. However, once the output power decreases, the voltage may rise again, resulting in inaccurate mileage calculations.

[0003] Of course, there are similar fuel meter products in the existing technology, which measure the current and voltage of the battery at the same time and calculate the remaining power according to the coulomb method. Compared with the above-mentioned voltage method, the measurement is slightly more accurate, but the interface of these products is not user-friendly, resulting in the instrument used for display requiring a separate one-line data cable for docking. At the same time, considering that different users will use different types of batteries, such as lead-acid, lithium iron phosphate, ternary lithium batteries, etc., these fuel meters are often unable to make accurate judgments and precise calculations. Utility Model Content

[0004] Therefore, the purpose of the present invention is to provide a fuel meter for light electric vehicles, which adopts a fuel calculation and battery health solution that combines Coulomb calculation and dynamic internal resistance measurement to improve the accuracy of fuel calculation, and adopts the LIN bus interface standard and adds Bluetooth BLE wireless connection function to facilitate data docking of the entire vehicle system, and can obtain information even without a wired connection.

[0005] To solve the above technical problems, according to one aspect of the present invention, the present invention provides the following technical solution: a fuel meter for a light electric vehicle, comprising a B+ input terminal, a B- output terminal and a P- terminal, a voltage sampling circuit being provided between the B+ input terminal and the B- output terminal, and a fuel meter IC being connected in series on one side of the voltage sampling circuit, a current sampling resistor being connected in series between the B- output terminal and the P- terminal, and a Bluetooth MCU being connected in series on the B+ input terminal.

[0006] As a preferred solution of the power meter of a light electric vehicle described in the utility model, it also includes a DC conversion module, which is connected in series with the Bluetooth MCU, and the DC conversion module is used to convert the DC voltage into a voltage that meets the requirements of the electronic device.

[0007] As a preferred solution of the power meter of a light electric vehicle described in the utility model, it also includes a LIN bus interface. The LIN bus interface is a bidirectional transmission interface, and the power meter parameters are set and the power meter statistical information is read through the LIN bus.

[0008] As a preferred solution of the fuel meter for a light electric vehicle described in the present invention, the B+ input terminal and the B- output terminal are respectively connected to the two ends of the battery pack.

[0009] As a preferred solution of the fuel meter for a light electric vehicle described in the utility model, the current sampling resistor is used to collect the input and output currents of the battery pack.

[0010] As a preferred solution of the power meter for a light electric vehicle described in the utility model, the P-terminal is connected to a load.

[0011] As a preferred solution for the fuel meter of a light electric vehicle described in the utility model, the fuel meter IC is used for Coulomb method calculation to count the discharge and charge power of the battery pack, and then sends it to the Bluetooth MCU for statistical calculation to obtain the remaining power of the battery pack.

[0012] Compared with the prior art, the advantages of the present invention are:

[0013] 1. Through the voltage acquisition circuit, fuel meter IC, and current sampling resistor, coulomb calculation plus dynamic resistance measurement are used. In addition to counting the remaining power of the battery pack after charging and discharging, the dynamic internal resistance of the battery can also be calculated based on the load current and the change in output voltage. If the dynamic internal resistance reaches a certain level, an alarm message will be output to facilitate user replacement / repair.

[0014] 2. The interface adopts the industrial standard LIN bus interface, which is convenient for the whole vehicle system to connect data. The LIN bus is also bidirectional. The fuel gauge parameters can be set through the LIN bus, and the fuel gauge statistical information can also be read.

[0015] 3. Added Bluetooth BLE communication, you can use the mobile phone APP to connect to the fuel meter to obtain the dynamic internal resistance of the power, and can set battery parameters, or provide firmware OTA upgrades. BLE communication can also connect to other smart devices in the vehicle, so that information can be obtained even without a wired connection.

[0016] 4. Introduction and use of large-capacity battery parameter tables. These parameters include voltage and internal resistance parameters at different temperatures, different remaining capacity (SOC), and different discharge rates. The temperature sensor, current sensor, and voltage sensor built into the fuel gauge IC can be used to calculate the current battery pack parameters and compare them with this large-capacity parameter table to correct the SOC and battery health (SOH) data. These parameters can be downloaded to the fuel gauge via the LIN bus and Bluetooth BLE wireless communication. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the present invention will be described in detail below in conjunction with the accompanying drawings and detailed embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without inventive labor. Among them:

[0018] Figure 1 This is a system schematic diagram of the present utility model.

[0019] In the figure: 1. B+ input terminal; 2. B- output terminal; 3. Voltage sampling circuit; 4. Fuel meter IC; 5. Current sampling resistor; 6. DC conversion module; 7. Bluetooth MCU; 8. LIN bus interface; 9. P- terminal. DETAILED DESCRIPTION

[0020] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0021] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. People skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific implementation methods disclosed below.

[0022] Next, the present invention is described in detail with reference to schematic diagrams. For ease of illustration, cross-sectional views of device structures may be partially enlarged and not to scale when describing the embodiments of the present invention. Furthermore, the schematic diagrams are merely illustrative and should not limit the scope of protection of the present invention. Furthermore, in actual production, three-dimensional dimensions, including length, width, and depth, should be included.

[0023] In order to make the purpose, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0024] The utility model provides a fuel meter for light electric vehicles, which adopts a fuel calculation and battery health solution that combines coulomb calculation and dynamic internal resistance measurement to improve the accuracy of fuel calculation. It also adopts the LIN bus interface standard and adds Bluetooth BLE wireless connection function to facilitate data docking of the entire vehicle system and can obtain information even without a wired connection.

[0025] Figure 1 The figure shows the overall structure of an embodiment of a fuel meter for a light electric vehicle of the present invention. Figure 1 The main structure of this embodiment includes a B+ input terminal 1, a B- output terminal 2 and a P- terminal 9. A voltage sampling circuit 3 is provided between the B+ input terminal 1 and the B- output terminal 2, and a power meter IC 4 is connected in series to one side of the voltage sampling circuit 3. A current sampling resistor 5 is connected in series between the B- output terminal 2 and the P- terminal 9, and a Bluetooth MCU 7 is connected in series to the B+ input terminal 1.

[0026] It also includes a DC conversion module 6, which is connected in series with the Bluetooth MCU 7, and is used to convert a DC voltage into a voltage that meets the requirements of the electronic device;

[0027] The LIN bus interface 8 is a bidirectional transmission interface, and the parameters of the electricity meter are set and the statistical information of the electricity meter is read through the LIN bus.

[0028] During specific use, the voltage sampling circuit 3 is used to collect the circuit voltage, and the current sampling resistor 5 collects the input and output current of the battery pack. At this time, the collected voltage and current data are input into the fuel gauge IC4 to implement the Coulomb method calculation, count the discharge and charge power of the battery pack, and then send it to the Bluetooth MCU7 for statistical calculation to obtain the remaining power of the battery pack. The Bluetooth MCU7 communicates with external devices through the LIN bus interface 8 and Bluetooth BLE;

[0029] The fuel gauge IC4 chip detects the voltage on the current sampling resistor 5, converts it into current, and multiplies it with the voltage value to calculate the amount of electricity flowing. During discharge, the total current P- flows to B-, and the SOC gradually decreases. During charging, the electricity flows from B- to P-, and the SOC gradually increases.

[0030] During discharge, the dynamic internal resistance of the battery pack can be calculated by detecting changes in voltage and current. The dynamic internal resistance is directly correlated with SOC and temperature. By measuring the dynamic internal resistance, the SOC of the battery pack can be obtained more accurately. At the same time, the SOH status of the battery pack can also be determined by comparing it with historical records.

[0031] While the present invention has been described above with reference to specific embodiments, various modifications may be made and equivalent components may be substituted without departing from the scope of the present invention. In particular, as long as no structural conflicts exist, the various features of the embodiments disclosed herein may be combined with one another in any manner, and the omission of an exhaustive description of these combinations in this specification is solely for the sake of space and resource conservation. Therefore, the present invention is not limited to the specific embodiments disclosed herein, but encompasses all technical solutions within the scope of the claims.

Claims

1. A fuel meter for a light electric vehicle, comprising a B+ input terminal (1), a B- output terminal (2) and a P- terminal (9), characterized in that: A voltage sampling circuit (3) is provided between the B+ input terminal (1) and the B- output terminal (2), and a power meter IC (4) is connected in series to one side of the voltage sampling circuit (3); a current sampling resistor (5) is connected in series between the B- output terminal (2) and the P- terminal (9); and a Bluetooth MCU (7) is connected in series to the B+ input terminal (1).

2. The fuel meter for a light electric vehicle according to claim 1, characterized in that: It also includes a DC conversion module (6), which is connected in series with the Bluetooth MCU (7), and is used to convert a direct current voltage into a voltage that meets the requirements of the electronic device.

3. The fuel meter for a light electric vehicle according to claim 2, characterized in that: It also includes a LIN bus interface (8), which is bidirectional, and is used to set the electricity meter parameters and read the electricity meter statistical information via the LIN bus.

4. The fuel meter for a light electric vehicle according to claim 3, characterized in that: The B+ input terminal (1) and the B- output terminal (2) are respectively connected to the two ends of the battery pack.

5. The fuel meter for a light electric vehicle according to claim 4, characterized in that: The current sampling resistor (5) is used to collect the input and output currents of the battery pack.

6. The fuel meter for a light electric vehicle according to claim 5, characterized in that: The P-terminal (9) is connected to a load.

7. The fuel meter for a light electric vehicle according to claim 6, characterized in that: The electricity meter IC (4) is used for Coulomb method calculation to count the discharge and charge electricity of the battery pack, and then sends the statistics to the Bluetooth MCU (7) for statistical calculation to obtain the remaining electricity of the battery pack.

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