Intelligent instrument of electric vehicle

Abstract

The invention discloses an intelligent instrument of an electric vehicle. The intelligent instrument comprises a high-speed change-over switch, the acquisition module is electrically connected with the high-speed change-over switch, and the high-speed change-over switch is electrically connected with the motor temperature sensor and the controller temperature measurement circuit; wherein the motor temperature sensor is disconnected with the controller temperature measurement circuit, the acquisition module transmits an analog voltage signal to the controller temperature measurement circuit, acquires a voltage signal of the motor temperature sensor and analyzes the voltage signal into temperature, the high-speed change-over switch rapidly returns to a connection state, and the motor temperature sensor is disconnected with the controller temperature measurement circuit. The motor temperature sensor is reconnected with the controller temperature measuring circuit, and data measured by the motor temperature sensor are transmitted to the controller in real time. According to the invention, the model limit of the original controller of the electric vehicle can be ignored, and the temperature signal can be dynamically, reliably, quickly and losslessly acquired.

Description

Technical Field

[0001] The invention relates to an intelligent instrument for an electric vehicle. Background Art

[0002] Two-wheeled electric vehicles include electric bicycles and electric motorcycles. Electric bicycles and electric motorcycles use batteries as auxiliary energy and motors as power sources. The batteries supply power to the motors, which drive the wheels to rotate, allowing the electric bicycles and electric motorcycles to move.

[0003] Usually, a temperature sensor is integrated inside the motor, which can monitor the temperature of the motor in real time. The temperature transmission depends on the temperature line, and the controller parses the temperature sensor signal through the corresponding logic to achieve temperature detection. In the traditional temperature acquisition process, assuming that the model and internal logic of the controller are known (such as internal power supply voltage, pull-up resistor value, etc.), the sampling logic is fixed: if the motor end of the temperature line is T1 and the controller end is T2; the controller samples the voltage signal of T1, combines the characteristic table of the temperature sensor, converts its resistance value into voltage, and further converts it into the corresponding temperature value through specific logic. However, in actual applications, the temperature acquisition logic of controllers of different models varies greatly, the controller protocol may be unknown, and the power supply characteristics and pull-up resistors cannot be directly obtained, which makes the traditional sampling method have bottlenecks in cross-controller compatibility.

[0004] In addition, the power supply (voltage) range of the controller to the motor Hall sensor in the current market is 4V to 18V. After measurement and analysis, it is found that the current that can be provided is 20mA to 100mA. However, the operating voltage range of the Bluetooth chip in the submodule is 3.0V to 3.6V, and the instantaneous maximum current is 30mA. The power supply voltage of 4V to 18V is higher than the operating voltage of the Bluetooth chip of 3.0V to 3.6V, and the power supply current of 20mA to 30mA is lower than the instantaneous maximum current of the submodule Bluetooth chip of 30mA. Obviously, the Bluetooth chip cannot operate normally. Therefore, in view of the defects of the prior art, an electric vehicle intelligent meter is developed. Summary of the invention

[0005] The purpose of the present invention is to provide an electric vehicle intelligent meter to address the defects of the prior art.

[0006] In order to achieve the above-mentioned purpose of the present invention, the following technical scheme is adopted: An electric vehicle intelligent instrument comprises a high-speed switching switch; and an acquisition module, wherein the acquisition module is electrically connected to the high-speed switching switch, and the high-speed switching switch is electrically connected to a motor temperature sensor and a controller temperature measurement circuit; wherein the motor temperature sensor is disconnected from the controller temperature measurement circuit, and the acquisition module sends an analog voltage signal to the controller temperature measurement circuit while acquiring the voltage signal of the motor temperature sensor and analyzing it as temperature, the high-speed switching switch quickly returns to a connected state, the motor temperature sensor is reconnected to the controller temperature measurement circuit, and the data measured by the motor temperature sensor is transmitted to the controller in real time.

[0007] Furthermore, the high-speed switching switch includes two single-pole double-throw switches, the two single-pole double-throw switches are electrically connected to the controller temperature measurement circuit and the acquisition module, and one of the two single-pole double-throw switches is electrically connected to the motor temperature sensor and the acquisition module. Furthermore, the acquisition module includes an analog switch; a single-chip microcomputer, the single-chip microcomputer is electrically connected to the analog switch, and the analog switch is used to control the switching of the high-speed switching switch; and a signal transmission circuit, the single-chip microcomputer is electrically connected to the high-speed switching switch through the signal transmission circuit.

[0008] The signal transmission circuit includes an operational amplifier follower circuit and a low-pass filter circuit, and the operational amplifier follower circuit and the low-pass filter circuit are electrically connected in series.

[0009] Furthermore, one end of the low-pass filter circuit is electrically connected to the single-chip microcomputer, and the other end is electrically connected to the analog switch through an operational amplifier follower circuit; the low-pass filter circuit includes R16, R17, C24 and C25, one end of R16 is electrically connected to the single-chip microcomputer, and the other end is connected to R17 and one end of C24, the other end of R17 is electrically connected to one end of C25 and the operational amplifier follower circuit, and the other ends of C24 and C25 are both connected to a common ground wire.

[0010] Furthermore, one end of the low-pass filter circuit is electrically connected to the analog switch, and the other end is connected to the op amp follower circuit, and the op amp follower circuit is electrically connected to the single-chip computer; the low-pass filter circuit includes C23, one end of C23 and a pin of the analog switch are connected to a common ground line, and the other end is electrically connected to the op amp follower circuit.

[0011] Furthermore, an electric vehicle smart meter of the present invention also includes a 3.3V power supply circuit, which is electrically connected to the analog switch; the 3.3V power supply circuit includes a DC-DC circuit and an LDO circuit, which are connected in parallel with each other.

[0012] Furthermore, an electric vehicle smart meter of the present invention also includes a first Bluetooth, a second Bluetooth and a Bluetooth repeater; the Bluetooth repeater is placed between the first Bluetooth and the second Bluetooth; the first Bluetooth is close to the electric vehicle battery, paired with the Bluetooth built into the electric vehicle battery, and transmits signals with the Bluetooth repeater to complete short-range stable communication; the Bluetooth repeater transmits signals with the second Bluetooth, and the second Bluetooth is paired with the on-board meter located at the front of the electric vehicle to complete the relay transmission of battery information.

[0013] Furthermore, the electric vehicle smart meter of the present invention also includes a Lora communication module. The on-board meter is provided with a Lora communication module, and data can be transmitted between two Lora communication modules.

[0014] Furthermore, the electric vehicle intelligent meter of the present invention further includes a speed calibration module, which collects the motor Hall signal frequency (f) and GPS speed data (v), combines the timestamp synchronization algorithm to intelligently identify the valid data interval, and completes the accurate automatic calibration of the frequency and speed proportional factor (a); The working steps of the speed calibration module are as follows: (1) Data collection; The speed calibration module obtains the frequency signal (f) from the motor Hall sensor and records the data; Get real-time speed data through the GPS module (v); Accurately time-stamp each set of collected data to ensure synchronization in subsequent analysis; each set of data includes frequency f and speed v; (2) GPS data screening and validity judgment; Verify GPS signal integrity, remove high jump or delayed data, and exclude unreliable data; (3) Dynamic timestamp matching: accurately align the timestamp of GPS velocity v with the acquisition timestamp of Hall frequency f; (4) Automatic calibration and scale factor calculation; After the timestamps are aligned, the mean value of a is calculated, and the speed calibration is completed; (5) GPS-independent adaptive speed measurement; repeating steps (1) to (4) to achieve dynamic calibration of speed.

[0015] 1. The high-speed switch of the present invention adopts a high-precision fast switching chip. The total time of switching the switch off and on is only 50ns, which can effectively avoid signal interruption caused by long-term disconnection. During the entire switching period, the analog voltage keeps the controller signal consistent, ensuring that the output temperature does not show obvious jumps or abnormalities, so that the controller continues to work in a stable state without misjudging temperature changes.

[0016] 2. The time (within 0.1 seconds) for the acquisition module of the present invention to collect temperature and analyze data is much shorter than the actual temperature change time, ensuring data accuracy. The acquisition module is designed to collect data once per second, which greatly reduces the interference with the working logic of the traditional controller, ensures that the controller outputs a stable temperature signal during the acquisition cycle, and eliminates the risk of data jumps and distortion.

[0017] 3. The present invention keeps the original circuit stable through analog voltage, and the entire acquisition process does not damage the controller logic and the original system function. The independent analysis logic of the acquisition module makes it adaptable to different models of controllers in the market without analyzing their internal characteristics. The modular design is suitable for a variety of application scenarios, and can be plug-and-play without complex debugging. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for the specific embodiments or the description of the prior art. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn according to the actual scale.

[0019] Figure 1 A circuit diagram of an electric vehicle intelligent instrument according to the present invention; Figure 2 It is a schematic diagram of the principle structure of the present invention; Names and serial numbers of components in the figure: In the circuit diagram: R represents resistance and C represents capacitance. DETAILED DESCRIPTION

[0020] In order to enable those skilled in the art to better understand the technical solutions in the present application, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and embodiments. Obviously, the described embodiments are only part of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work should fall within the scope of protection of the present application. Example

[0021] like Figure 1 , 2As shown, an electric vehicle intelligent instrument also includes a high-speed switching switch and a collection module. The collection module is electrically connected to the high-speed switching switch, and the high-speed switching switch is electrically connected to the motor temperature sensor and the controller temperature measurement circuit; wherein, the motor temperature sensor is disconnected from the controller temperature measurement circuit, and the collection module sends an analog voltage signal to the controller temperature measurement circuit while collecting the voltage signal of the motor temperature sensor and analyzing it as temperature, the high-speed switching switch quickly returns to the connection state, the motor temperature sensor is reconnected to the controller temperature measurement circuit, and the data measured by the motor temperature sensor is transmitted to the controller in real time.

[0022] It is understandable that the temperature collected by the collection module is displayed through the intelligent instrument.

[0023] It should be noted that the electric vehicle intelligent instrument of the present invention is an improvement on the original on-board instrument of the electric vehicle.

[0024] The motor end of the temperature line is T1, and the controller end is T2; the controller samples the voltage signal of T1, combines the characteristic table of the temperature sensor, converts its resistance value into voltage, and further converts it into the corresponding temperature value through specific logic.

[0025] How collection works: The first step is the initial state.

[0026] Under normal working conditions, T1 (motor temperature sensor end) is directly connected to T2 (controller end), and the controller reads the temperature signal through the set logic to complete the conventional temperature analysis. During this period, the acquisition module passively simulates the voltage signal of T1 and records the voltage value currently transmitted by the original line.

[0027] The second step is to switch the acquisition mode.

[0028] A high-speed switch is introduced to switch the temperature line to two states: Connection status: T1 is directly connected to T2, and the controller works normally; Acquisition status: Disconnect T1 and T2, connect T1 to the acquisition module, and connect T2 to an analog voltage generator.

[0029] Third, the analog voltage keeps the controller stable. During the switch to the acquisition state, the controller receives an analog voltage signal from T2. The analog voltage signal is accurately generated by the acquisition module based on the previously simulated original T1 voltage, and is completely consistent with the original voltage. Therefore, the controller cannot sense that the circuit has been switched, and continues to receive stable "false signals". The temperature display and control do not need to be corrected, and the original control logic is completely unaffected.

[0030] Fourth, the acquisition module completes temperature analysis.

[0031] At the moment T1 is switched to the acquisition module, the acquisition module analyzes the motor temperature signal into the actual temperature based on the actual voltage signal of T1 collected and combined with the module's own conversion logic. The acquisition module only takes 5 to 10 ms to complete the entire analysis process, and the time required for each ℃ temperature change is at least 1 second, which is much shorter than the time for the controller temperature display to update.

[0032] Fifth, restore to the original state.

[0033] After the acquisition is completed, the switch quickly returns to the connected state, T1 and T2 are reconnected, and the original line returns to the initial state. The controller continues to complete its original analysis logic based on the signal of the temperature sensor.

[0034] The switch uses a high-precision fast switching chip. The total time for the switch to be disconnected and connected is only 50ns, which can effectively avoid signal interruption caused by long-term disconnection. During the entire switching period, the analog voltage keeps the controller signal consistent, ensuring that the output temperature does not show obvious jumps or abnormalities, so that the controller continues to work in a stable state and does not misjudge temperature changes.

[0035] Temperature is not a physical quantity that changes rapidly. The temperature of the motor is affected by heat dissipation, and its change is usually in the order of seconds. Therefore, the time (within 0.1 seconds) for the acquisition module to collect temperature and analyze data is much shorter than the actual temperature change time, ensuring data accuracy. The acquisition module is designed to collect data once per second, which greatly reduces the interference with the working logic of the traditional controller, ensures that the controller outputs a stable temperature signal during the acquisition cycle, and eliminates the risk of data jumps and distortion.

[0036] The original circuit is kept stable by simulating voltage, and the entire acquisition process does not damage the controller logic and the original system function. The independent analysis logic of the acquisition module makes it adaptable to different models of controllers in the market without analyzing their internal characteristics. The modular design is suitable for a variety of application scenarios, and can be plug-and-play without complex debugging.

[0037] In some optional embodiments, a structure of an acquisition module is provided. The acquisition module includes an analog switch, a single-chip microcomputer, and a signal transmission circuit. The single-chip microcomputer is electrically connected to the analog switch, and the analog switch is used to control the switching of the high-speed switching switch; the single-chip microcomputer and the high-speed switching switch are electrically connected through the signal transmission circuit.

[0038] It should be noted that one structure of the high-speed switch includes two single-pole double-throw switches, the two single-pole double-throw switches are electrically connected to the controller temperature measurement circuit and the acquisition module, and one of the two single-pole double-throw switches is electrically connected to the motor temperature sensor and the acquisition module. Figure 1 As shown, the two single-pole double-throw switches are SW1 and SW2 respectively.

[0039] like Figure 2 As shown, one structure of the analog switch may be GS3005-MR.

[0040] The signal transmission circuit comprises an operational amplifier follower circuit and a low-pass filter circuit, and the operational amplifier follower circuit and the low-pass filter circuit are electrically connected in series.

[0041] The op amp follower circuit includes an operational amplifier. Figure 2 As shown, one structure of the operational amplifier may be GS358-MR.

[0042] like Figure 1 , 2 As shown, pin 3 of GS3005-MR is connected to pin 1 and pin 2 of GS358-MR. Pin 4 of GS3005-MR is connected to pin 4 of the microcontroller to control the switch of SW2. Pin 8 of GS3005-MR is connected to pin 3 of the microcontroller to control the switch of SW1. Pin 9 of GS3005-MR is connected to the motor temperature sensor. Pin 10 of GS3005-MR is connected to the temperature measurement circuit of the electric vehicle controller, and pin 10 is also connected to pin 2. Pin 7 of GS3005-MR is connected to one end of R12, and the other end of R12 is connected to the 3.3V power supply circuit. Pin 1 of GS3005-MR is connected to the 3.3V power supply circuit and one end of C20, and the other end of C20 is connected to the common ground line.

[0043] Pin 8 of GS358-MR is connected to the common ground of GS3005-MR through C23. Pin 5 of GS358-MR is connected to one end of R18, the other end of R18 and one end of C26 are connected to pin 9 of GS3005-MR, and the other end of C26 is connected to the common ground. Pins 6 and 7 of GS358-MR are connected to MCU_ADC and pin 1 of the microcontroller. MCU_ADC can be an onboard instrument of an electric vehicle. Pin 4 of GS358-MR is connected to the common ground.

[0044] In some optional embodiments, a low-pass filter circuit structure of a single-chip microcomputer and an analog switch is provided. One end of the low-pass filter circuit is electrically connected to the single-chip microcomputer, and the other end is electrically connected to the analog switch through an operational amplifier follower circuit; the low-pass filter circuit includes R16, R17, C24 and C25, one end of R16 is electrically connected to the single-chip microcomputer, and the other end is connected to R17 and one end of C24, the other end of R17 is electrically connected to one end of C25 and the operational amplifier follower circuit, and the other ends of C24 and C25 are both connected to a common ground line.

[0045] In some optional embodiments, another low-pass filter circuit structure of the single-chip microcomputer and the analog switch is provided. One end of the low-pass filter circuit is electrically connected to the analog switch, and the other end is connected to the operational amplifier follower circuit, and the operational amplifier follower circuit is electrically connected to the single-chip microcomputer; the low-pass filter circuit includes C23, one end of C23 and a pin of the analog switch are connected to a common ground line, and the other end is electrically connected to the operational amplifier follower circuit.

[0046] In some optional embodiments, a power supply circuit structure is provided, wherein a 3.3V power supply circuit is additionally installed, and the 3.3V power supply circuit is electrically connected to an analog switch.

[0047] The 3.3V power supply circuit includes a DC-DC circuit and an LDO circuit, and the DC-DC circuit and the LDO circuit are connected in parallel.

[0048] Specifically, the DC-DC and LDO are connected in parallel, the input voltage range is 4V~18V, and the output voltage range is 3.3V~3.4V; when the input voltage is greater than or equal to 4V and less than 5V, the output voltage of the DC-DC circuit is less than 3.3V at this time because the minimum input voltage of the DC-DC circuit is not reached, while the LDO circuit works normally and the output voltage is 3.3V, so it automatically switches to LDO; when the input voltage is greater than or equal to 5V, the DC-DC works normally and the output voltage is 3.4V, which is greater than the output voltage of 3.3V of the LDO. According to the physical principle that "if two power supplies provide current at the same time, the current will automatically flow out from the power supply with a higher voltage", the current will flow out of the DC-DC circuit first, that is, it will automatically switch to the DC-DC circuit; thereby realizing the use of a weak power supply to power the Bluetooth chip.

[0049] In some optional embodiments, in order to overcome the problems of weak signal and unstable connection often existing when the on-board instrument directly communicates with the battery through Bluetooth, the on-board instrument is provided with a first Bluetooth, a second Bluetooth and a Bluetooth repeater; the Bluetooth repeater is placed between the first Bluetooth and the second Bluetooth; the first Bluetooth is close to the battery of the electric vehicle, paired with the Bluetooth built into the battery of the electric vehicle, and transmits signals with the Bluetooth repeater to complete stable communication over short distances; the Bluetooth repeater transmits signals with the second Bluetooth, and the second Bluetooth is paired with the on-board instrument located at the front of the vehicle to complete the relay transmission of battery information.

[0050] Bluetooth repeater is a device that enhances the coverage and stability of Bluetooth signals. Its main function is to receive Bluetooth signals and retransmit them, thereby expanding the communication range of Bluetooth devices and ensuring a stable Bluetooth connection even in larger spaces or complex environments.

[0051] It is understandable that the first Bluetooth is set close to the electric vehicle battery, forming a near-field Bluetooth connection. The second Bluetooth is close to the vehicle instrument, forming a far-field Bluetooth. The first Bluetooth and the second Bluetooth realize battery signal transmission and transfer through the Bluetooth repeater to achieve a stable Bluetooth connection.

[0052] The present invention adds a Bluetooth repeater between the first Bluetooth and the second Bluetooth, and utilizes the signal transmission characteristics between Bluetooth to overcome the limitations of battery physical shielding and transmission distance, thereby achieving a stable Bluetooth connection between the instrument and the battery.

[0053] It should be noted that the acquisition module uses a non-metallic shell to reduce its own signal shielding and improve the stability of the Bluetooth connection.

[0054] In some optional embodiments, in order to improve the single functionality of the existing vehicle-mounted instrument, a Lora communication module is added. The vehicle-mounted instrument is provided with a Lora communication module, and data can be transmitted between two Lora communication modules.

[0055] It should be noted that the functions of traditional vehicle-mounted instruments are relatively simple, usually only displaying basic information such as speed and power, which is difficult to meet the growing social needs of users. The present invention introduces Lora wireless communication technology to realize social functions such as location sharing, friend search, and distance display on vehicle-mounted instruments, which significantly improves the user experience.

[0056] Specifically, the working method: Lora module integration: Integrate the Lora communication module in the vehicle instrument to realize data transmission function.

[0057] Friend search and pairing: Use the instrument to search for nearby Lora devices and select friends for pairing.

[0058] Location data sharing: After pairing is complete, location information can be shared between devices to display the distance to friends.

[0059] Data transmission: Users can transmit short messages such as text or status through Lora to increase interactivity.

[0060] The present invention utilizes the long-distance and low-power characteristics of Lora technology to enhance the communication capability of the instrument and realize social functions. Through the Lora positioning function, the location sharing between users is realized, and the interactivity of the instrument is enhanced. The Lora technology can also be combined with the vehicle-mounted instrument to add social functions to the vehicle-mounted instrument and enhance the user experience.

[0061] In some optional embodiments, in order to dynamically calibrate the speed of the electric vehicle, a speed calibration module is added. The speed calibration module collects the motor Hall signal frequency (f) and GPS speed data (v), and combines the timestamp synchronization algorithm to intelligently identify the valid data interval, and completes the accurate automatic calibration of the frequency and speed proportional factor (a).

[0062] It should be noted that in traditional speed measurement, the motor Hall signal is used as an important source of speed acquisition. The frequency (f) of the Hall signal reflects the motor speed. For each motor model, there must be a proportional relationship between the frequency and the vehicle speed (v) (v=a*f, a is the proportional coefficient). However, the conversion ratio between the motor speed and the vehicle speed of different models may be different; tire size, tire pressure changes, etc. will also affect the conversion relationship between frequency and vehicle speed.

[0063] When GPS is currently combined with GPS for speed calibration, GPS has the following limitations: Unstable signal: tall buildings, basements, tunnels, and even weather conditions can interfere with GPS signals; High latency and low refresh rate: GPS lacks real-time performance and cannot meet the needs of rapidly changing vehicle speeds; Poor experience: GPS speed data depends on the environment, and multiple signal interruptions may cause calibration failure.

[0064] The present invention can effectively overcome the limitations of existing electric vehicle GPS. The working steps of the speed calibration module of the present invention are as follows: (1) Data collection; The speed calibration module obtains the frequency signal (f) from the motor Hall sensor and records the data; Get real-time speed data through the GPS module (v); Each set of collected data is accurately time-stamped to ensure synchronization in subsequent analysis; each set of data includes frequency f and speed v.

[0065] (2) GPS data screening and validity judgment; Verify GPS signal integrity, remove high-transition or delayed data, and exclude unreliable data.

[0066] (3) Dynamic timestamp matching: accurately align the timestamp of GPS velocity v with the acquisition timestamp of Hall frequency f.

[0067] It should be noted that due to the different time intervals and rates of GPS speed data and Hall frequency data collection, the raw data are usually not synchronized. For example: GPS collects three data V1, V2, and V3 at the 1st, 2nd, and 3rd seconds respectively, and the acquisition module collects five data f1, f1.5, f2, f2.5, and f3 at the 1st, 1.5, 2nd, 2.5, and 3rd seconds respectively, and then accurately aligns the timestamp of GPS speed v with the acquisition timestamp of Hall frequency f, that is, V1 is aligned with f1, V2 is aligned with f2, and V3 is aligned with f3.

[0068] (4) Automatic calibration and proportional factor calculation: After the timestamps are aligned, the mean value of a is calculated to complete the speed calibration.

[0069] (5) GPS-independent adaptive speed measurement; the speed calibration module will repeat the above process and loop steps (1) to (4) when the above conditions are met to achieve dynamic speed calibration.

[0070] It should be noted that GPS signals may be lost or have large errors due to environmental influences. The present invention introduces a signal screening algorithm to ensure that calibration is based only on high-reliability data by verifying data continuity, fit and stability interval.

[0071] GPS has a low refresh rate and high latency, and is not synchronized with the data collected by the module. For this reason, the present invention adopts a timestamp synchronization mechanism to accurately match the time of the two signal sources, thereby completing the calibration of reliable data.

[0072] The present invention adapts to various motor models and tire sizes by automatically calibrating the proportional factor a, and completes automatic speed calibration without manual intervention.

[0073] According to the above embodiment, the present invention is used to intercept the motor temperature data of electric bicycles and electric motorcycles. The motor temperature is obtained by using the original motor temperature sensor circuit of the electric vehicle without affecting the normal operation of the electric vehicle controller. The motor temperature intercepted by the circuit can be provided to the expansion device (which can be a vehicle-mounted instrument) for use.

[0074] Working principle of the present invention: ① When the circuit of the present invention is powered on and started, the IO pin No. 3 of the single-chip microcomputer outputs a level signal to the control pin of SW1, so that the pin No. 1 and the pin No. 2 of SW1 are connected (the pin No. 1 and the pin No. 3 of SW1 are disconnected). At this time, the electric vehicle controller can normally collect the motor temperature; at the same time, the single-chip microcomputer collects the intermediate node 1 and the node 2 (i.e., the voltage divider circuit formed by the motor temperature sensor and the internal pull-up resistor of the electric vehicle controller) through the ADC function. Figure 1The microcontroller then outputs a PWM signal through PWM pin 2, which is filtered by a low-pass filter circuit to obtain a voltage V2 close to V1, so that the voltage at node 3 is V2.

[0075] ②The MCU IO pin 4 outputs a level signal to the control pin of SW2, making the SW2 pins 1 and 2 connected, and the voltages of nodes 1, 2 and 3 are the same, all V2; at this time, the MCU collects the voltage V2 of node 1 again through the ADC function, and after calculation, the MCU outputs a PWM signal through the PWM pin 2 again, and after filtering by the low-pass filter circuit, a voltage is obtained so that the voltage at node 2 is V1, that is, through closed-loop control, V2 is approximately equal to V1. After completing the above process, the voltage on node 2 (temperature measurement line at the electric vehicle controller end) can be maintained at V1.

[0076] ③After completing the above processes ① and ②, the MCU IO pin 3 outputs a level signal to the SW1 control pin, making the SW1 pins 1 and 3 connected (SW1 pins 1 and 2 disconnected). The external 3.3V-10K pull-up resistor and the electric vehicle motor temperature sensor form the intermediate node 1 of the voltage divider measurement circuit. The MCU reads the voltage value of node 1 through the ADC pin and calculates the current temperature of the motor. The MCU can transmit the temperature data to the on-board instrument for use. At this time, the voltage on the temperature measurement line of the electric vehicle controller is maintained at V1. Although the temperature data obtained by the electric vehicle controller is not the real-time temperature of the current motor, the temperature data obtained by the electric vehicle controller will not jump or be abnormal.

[0077] ④ After completing the above processes ①, ② and ③, the MCU IO pin 3 outputs a level signal to the control pin of SW1, making SW1's pin 1 and pin 2 connected (SW1's pin 1 and pin 3 disconnected), and then the MCU IO pin 4 outputs a level signal to the control pin of SW 2, making SW2's pin 1 and pin 2 disconnected; at this time, the electric vehicle controller can normally measure the real-time data of the motor temperature sensor.

[0078] ⑤ Execute steps ①, ②, ③, and ④ in a reciprocating cycle to perfectly capture the temperature data of the electric vehicle motor temperature sensor circuit without affecting the normal operation of the electric vehicle controller.

[0079] Obviously, the above embodiments are merely examples for clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the protection scope of the invention.

Claims

1. An electric vehicle intelligent meter, characterized in that: Also includes High-speed switching; as well as A collection module, wherein the collection module is electrically connected to the high-speed switch, and the high-speed switch is electrically connected to the motor temperature sensor and the controller temperature measurement circuit; Among them, the motor temperature sensor is disconnected from the controller temperature measurement circuit, and the acquisition module sends an analog voltage signal to the controller temperature measurement circuit while acquiring the voltage signal of the motor temperature sensor and analyzing it as temperature. The high-speed switching switch quickly returns to the connection state, and the motor temperature sensor is reconnected to the controller temperature measurement circuit, and the data measured by the motor temperature sensor is transmitted to the controller in real time.

2. The electric vehicle smart meter according to claim 1, characterized in that: The high-speed switching switch includes two single-pole double-throw switches, the two single-pole double-throw switches are electrically connected to the controller temperature measurement circuit and the acquisition module, and one of the two single-pole double-throw switches is electrically connected to the motor temperature sensor and the acquisition module.

3. The electric vehicle smart meter according to claim 1 or 2, characterized in that: The acquisition module includes Analog switches; A single-chip microcomputer, the single-chip microcomputer is electrically connected to an analog switch, the analog switch is used to control the switching of the high-speed switching switch; and A signal transmission circuit, wherein the single chip microcomputer is electrically connected to the high-speed switching switch through the signal transmission circuit.

4. The electric vehicle smart meter according to claim 3, characterized in that: The signal transmission circuit includes an operational amplifier follower circuit and a low-pass filter circuit, and the operational amplifier follower circuit and the low-pass filter circuit are electrically connected in series.

5. The electric vehicle smart meter according to claim 4, characterized in that: One end of the low-pass filter circuit is electrically connected to the single-chip microcomputer, and the other end is electrically connected to the analog switch through an operational amplifier follower circuit; The low-pass filter circuit includes R16, R17, C24 and C25, one end of R16 is electrically connected to the single-chip microcomputer, and the other end is connected to one end of R17 and C24, the other end of R17 is electrically connected to one end of C25 and the operational amplifier follower circuit, and the other ends of C24 and C25 are both connected to a common ground line.

6. The electric vehicle smart meter according to claim 4, characterized in that: One end of the low-pass filter circuit is electrically connected to the analog switch, and the other end is connected to the operational amplifier follower circuit, and the operational amplifier follower circuit is electrically connected to the single-chip microcomputer; The low-pass filter circuit includes C23, one end of which is connected to a common ground line together with a pin of an analog switch, and the other end of which is electrically connected to an operational amplifier follower circuit.

7. The electric vehicle smart meter according to claim 3, characterized in that: Also includes a 3.3V power supply circuit, the 3.3V power supply circuit is electrically connected to the analog switch; The 3.3V power supply circuit includes a DC-DC circuit and an LDO circuit, and the DC-DC circuit and the LDO circuit are connected in parallel.

8. The electric vehicle smart meter according to claim 1, characterized in that: It also includes a first Bluetooth, a second Bluetooth and a Bluetooth repeater; the Bluetooth repeater is placed between the first Bluetooth and the second Bluetooth; The first Bluetooth is placed close to the battery of the electric vehicle, paired with the Bluetooth built into the battery of the electric vehicle, and transmits signals with the Bluetooth repeater to complete stable communication at a short distance; The Bluetooth repeater transmits signals to the second Bluetooth, and the second Bluetooth is paired with the on-board instrument located at the front of the electric vehicle to complete the relay transmission of battery information.

9. The electric vehicle smart meter according to claim 1, characterized in that: It also includes a Lora communication module. The vehicle-mounted instrument is provided with a Lora communication module, and data can be transmitted between two Lora communication modules.

10. The electric vehicle smart meter according to claim 1, characterized in that: It also includes a speed calibration module, which collects the motor Hall signal frequency (f) and GPS speed data (v), combines the timestamp synchronization algorithm to intelligently identify the valid data interval, and completes the accurate automatic calibration of the frequency and speed proportional factor (a); The working steps of the speed calibration module are as follows: (1) Data collection; The speed calibration module obtains the frequency signal (f) from the motor Hall sensor and records the data; Get real-time speed data through the GPS module (v); Accurately time-stamp each set of collected data to ensure synchronization in subsequent analysis; each set of data includes frequency f and speed v; (2) GPS data screening and validity judgment; Verify GPS signal integrity, remove high jump or delayed data, and exclude unreliable data; (3) Dynamic timestamp matching: accurately align the timestamp of GPS velocity v with the acquisition timestamp of Hall frequency f; (4) Automatic calibration and scale factor calculation; After the timestamps are aligned, the mean value of a is calculated, and the speed calibration is completed; (5) GPS-independent adaptive speed measurement; Repeat steps (1) to (4) to achieve dynamic calibration of speed.

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