阅读说明：本技术 一种电动车胎压监测方法及系统 (Tire pressure monitoring method and system for electric vehicle ) 是由 邱鹏 于 2020-12-28 设计创作，主要内容包括：本发明公开一种电动车胎压监测方法及系统,该方法包括：通过在电动车前轮安装的轮速传感器获得电动车前轮的轮速信号,通过在电动车后轮安装的轮速传感器获得电动车后轮的轮速信号；将所述电动车前轮的轮速信号和电动车后轮的轮速信号传输给处理单元；所述信号处理单元基于频域法和轮速比较法对收到的轮速信号进行处理,判断电动车前后车轮的胎压是否正常。本发明通过频域法和轮速比较法相结合的方式对轮速信号进行处理与标定,监测电动车胎压是否正常,最大限度的在报警前进行反复校对,有效的提高了准确率,降低了误报率。本发明提升了电动车骑行的安全性,减少事故的发生概率,避免在轮胎失压时造成的轮胎磨损加剧和续航里程减少。(The invention discloses a tire pressure monitoring method and a system for an electric vehicle, wherein the method comprises the following steps: the method comprises the steps that a wheel speed signal of a front wheel of the electric vehicle is obtained through a wheel speed sensor arranged on the front wheel of the electric vehicle, and a wheel speed signal of a rear wheel of the electric vehicle is obtained through a wheel speed sensor arranged on the rear wheel of the electric vehicle; transmitting the wheel speed signal of the front wheel of the electric vehicle and the wheel speed signal of the rear wheel of the electric vehicle to a processing unit; the signal processing unit processes the received wheel speed signal based on a frequency domain method and a wheel speed comparison method, and judges whether the tire pressure of front and rear wheels of the electric vehicle is normal or not. The invention processes and calibrates the wheel speed signal by combining a frequency domain method and a wheel speed comparison method, monitors whether the tire pressure of the electric vehicle is normal or not, and repeatedly calibrates the tire pressure before alarming to the maximum extent, thereby effectively improving the accuracy and reducing the false alarm rate. The invention improves the riding safety of the electric vehicle, reduces the occurrence probability of accidents, and avoids tire wear aggravation and endurance mileage reduction caused by tire pressure loss.)

1. An electric vehicle tire pressure monitoring method is characterized by comprising the following steps:

the method comprises the steps that a wheel speed signal of a front wheel of the electric vehicle is obtained through a wheel speed sensor arranged on the front wheel of the electric vehicle, and a wheel speed signal of a rear wheel of the electric vehicle is obtained through a wheel speed sensor arranged on the rear wheel of the electric vehicle;

transmitting the wheel speed signal of the front wheel of the electric vehicle and the wheel speed signal of the rear wheel of the electric vehicle to a processing unit;

the signal processing unit processes the received wheel speed signal based on a frequency domain method and a wheel speed comparison method, and judges whether the tire pressure of front and rear wheels of the electric vehicle is normal or not.

2. The tire pressure monitoring method for the electric vehicle according to claim 1, wherein the processing of the wheel speed signal based on the frequency method specifically comprises: firstly, the tyre is simplified into a spring-damper system; secondly, establishing a natural frequency identification model; then, estimating the natural frequency of the tire; finally, estimating the tire pressure state of the tire; wherein the identification of the natural frequency of the tire is realized by a frequency method.

3. The tire pressure monitoring method for the electric vehicle according to claim 2, wherein the frequency domain method is an algorithm for converting the wheel speed signal from a time domain signal to a frequency domain signal, and the algorithm includes but is not limited to fast fourier transform, wavelet transform, and auto-regression model.

4. The tire pressure monitoring method for electric vehicles according to claim 3, wherein the frequency domain method further comprises: and performing frequency domain analysis on the wheel speed signal by adopting an MA (mass spectroradiometer) model, an ARMA (autoregressive moving average) model and a PRONY (pro-specific exponential) model.

5. The tire pressure monitoring method for the electric vehicle according to claim 1, wherein the step of processing the received wheel speed signal based on a wheel speed comparison method specifically comprises: firstly, calibrating the wheel speeds of front wheels and rear wheels under the condition of normal tire pressure of the front wheels and the rear wheels of the electric vehicle by collecting the wheel speed signals of the front wheels of the electric vehicle and the wheel speed signals of the rear wheels of the electric vehicle within set time; secondly, comparing the collected Hall signal value of the wheel with a calibration value, and judging that the tire of the wheel is under-pressure after the collected Hall signal value of the wheel exceeds a set threshold value.

6. The tire pressure monitoring method for the electric vehicle as claimed in claim 1, wherein the wheel speed sensor is an active or passive speed sensor, including but not limited to hall wheel speed sensor, magneto-electric wheel speed sensor, photo-electric wheel speed sensor, magneto-resistive element wheel speed sensor.

7. The tire pressure monitoring method for the electric vehicle as claimed in claim 1, wherein the transmission modes of the signals for transmitting the wheel speed signals of the front wheel of the electric vehicle and the wheel speed signals of the rear wheel of the electric vehicle to the processing unit include, but are not limited to, RS-485 bus communication, CAN bus communication, Lin bus communication, RS-232 bus communication, Flexray communication, bluetooth communication, Wi-Fi communication and USB communication.

8. The electric vehicle tire pressure monitoring method according to claim 1, wherein the signal processing unit includes, but is not limited to, a single chip microcomputer, a controller, a central control unit, an MCU, and an ECU inside an electric vehicle meter.

9. The electric vehicle tire pressure monitoring method according to one of claims 1 to 8, further comprising: the tire pressure monitoring function is started and closed through a switch or an electric vehicle instrument.

10. An electric tire pressure monitoring system using the electric tire pressure monitoring method according to any one of claims 1 to 9, comprising: the device comprises a wheel speed sensor arranged on the front wheel of the electric vehicle, a wheel speed sensor arranged on the rear wheel and a processing unit; the wheel speed sensor arranged on the front wheel of the electric vehicle is used for acquiring a wheel speed signal of the front wheel of the electric vehicle; the wheel speed sensor arranged on the rear wheel of the electric vehicle is used for acquiring a wheel speed signal of the rear wheel of the electric vehicle; the processing unit is used for processing the received wheel speed signals based on a frequency domain method and a wheel speed comparison method and judging whether the tire pressures of the front wheel and the rear wheel of the electric vehicle are normal or not.

Technical Field

The invention relates to the technical field of tire pressure monitoring, in particular to a method and a system for monitoring tire pressure of an electric vehicle.

Background

The electric vehicle is a vehicle which takes a battery as an energy source, converts electric energy into mechanical energy through a controller, a motor and other components to move so as to control the current and change the speed. When the air pressure of the tyre is under pressure, the braking distance of the vehicle is lengthened, the stability is deteriorated, the abrasion of the tyre is aggravated, and the endurance mileage is reduced. The existing tire pressure monitoring scheme has two types of direct tire pressure monitoring and indirect tire pressure monitoring: firstly, direct tire pressure monitoring is carried out by utilizing a built-in or external sensor based on an English flying SP37 or similar chips, but the scheme is high in cost and difficult to popularize in electric vehicles. Two, indirect formula tire pressure monitoring utilizes the fast sensor of hall formula wheel or the fast sensor of magneto-electric wheel to obtain the tire rotational speed, carries out the comparison of front and back wheel rotational speed, judges whether tire pressure is normal, but this scheme precision is low, and easy wrong report, user experience is poor.

The above problems are urgently needed to be solved.

Disclosure of Invention

The invention aims to solve the problems mentioned in the background technology part by using a tire pressure monitoring method and a tire pressure monitoring system of an electric vehicle.

In order to achieve the purpose, the invention adopts the following technical scheme:

an electric vehicle tire pressure monitoring method, the method comprising:

the method comprises the steps that a wheel speed signal of a front wheel of the electric vehicle is obtained through a wheel speed sensor arranged on the front wheel of the electric vehicle, and a wheel speed signal of a rear wheel of the electric vehicle is obtained through a wheel speed sensor arranged on the rear wheel of the electric vehicle;

transmitting the wheel speed signal of the front wheel of the electric vehicle and the wheel speed signal of the rear wheel of the electric vehicle to a processing unit;

the signal processing unit processes the received wheel speed signal based on a frequency domain method and a wheel speed comparison method, and judges whether the tire pressure of front and rear wheels of the electric vehicle is normal or not.

In particular, the processing of the wheel speed signal based on the frequency method specifically includes: firstly, the tyre is simplified into a spring-damper system; secondly, establishing a natural frequency identification model; then, estimating the natural frequency of the tire; finally, estimating the tire pressure state of the tire; wherein the identification of the natural frequency of the tire is realized by a frequency method.

In particular, the frequency domain method refers to an algorithm for converting a wheel speed signal from a time domain signal to a frequency domain signal, and the algorithm includes, but is not limited to, fast fourier transform, wavelet transform, auto-regression model.

In particular, the frequency domain method further comprises: and performing frequency domain analysis on the wheel speed signal by adopting an MA (mass spectroradiometer) model, an ARMA (autoregressive moving average) model and a PRONY (pro-specific exponential) model.

In particular, the received wheel speed signal is processed based on a wheel speed comparison method, which specifically includes: firstly, calibrating the wheel speeds of front wheels and rear wheels under the condition of normal tire pressure of the front wheels and the rear wheels of the electric vehicle by collecting the wheel speed signals of the front wheels of the electric vehicle and the wheel speed signals of the rear wheels of the electric vehicle within set time; secondly, comparing the collected Hall signal value of the wheel with a calibration value, and judging that the tire of the wheel is under-pressure after the collected Hall signal value of the wheel exceeds a set threshold value.

In particular, the wheel speed sensor may be an active or passive speed sensor, including but not limited to a hall wheel speed sensor, a magneto-electric wheel speed sensor, a photo-electric wheel speed sensor, a magneto-resistive element wheel speed sensor.

Particularly, the transmission modes of the signals for transmitting the wheel speed signals of the front wheels of the electric vehicle and the wheel speed signals of the rear wheels of the electric vehicle to the processing unit include, but are not limited to, RS-485 bus communication, CAN bus communication, Lin bus communication, RS-232 bus communication, Flexray communication, Bluetooth communication, Wi-Fi communication and USB communication.

Particularly, the signal processing unit comprises but is not limited to a single chip microcomputer, a controller, a central control unit, an MCU and an ECU inside the electric vehicle instrument.

In particular, the electric vehicle tire pressure monitoring method further comprises the following steps: the tire pressure monitoring function is started and closed through a switch or an electric vehicle instrument.

Based on the electric vehicle tire pressure monitoring method, the invention also discloses an electric vehicle tire pressure monitoring system, which comprises the following steps: the device comprises a wheel speed sensor arranged on the front wheel of the electric vehicle, a wheel speed sensor arranged on the rear wheel and a processing unit; the wheel speed sensor arranged on the front wheel of the electric vehicle is used for acquiring a wheel speed signal of the front wheel of the electric vehicle; the wheel speed sensor arranged on the rear wheel of the electric vehicle is used for acquiring a wheel speed signal of the rear wheel of the electric vehicle; the processing unit is used for processing the received wheel speed signals based on a frequency domain method and a wheel speed comparison method and judging whether the tire pressures of the front wheel and the rear wheel of the electric vehicle are normal or not.

The electric vehicle tire pressure monitoring method and the electric vehicle tire pressure monitoring system process and calibrate the wheel speed signals in a mode of combining a frequency domain method and a wheel speed comparison method, monitor whether the electric vehicle tire pressure is normal or not, carry out repeated correction before alarming to the maximum extent, effectively improve the accuracy rate and reduce the false alarm rate. According to the invention, when the tire pressure of the electric vehicle is lower than the set threshold value, a rider is warned, the riding safety of the electric vehicle is improved, the occurrence probability of accidents is reduced, and the tire wear aggravation and the mileage reduction caused by the pressure loss of the tire are avoided. Compared with a direct tire pressure monitoring scheme for measuring the tire pressure by adopting a tire pressure monitoring chip, the invention reduces the dependence on the tire pressure monitoring chip of foreign manufacturers, greatly reduces the cost, enhances the commercial value of the application of the tire pressure monitoring function in the electric vehicle industry, and promotes the progress of the safety of the electric vehicle industry.

Drawings

Fig. 1 is a schematic flow chart of an electric vehicle tire pressure monitoring method provided by an embodiment of the invention;

fig. 2 is a schematic frequency-amplitude diagram of an electric vehicle with normal and abnormal tire pressure according to an embodiment of the present invention.

Detailed Description

The invention is further illustrated by the following figures and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It is also to be noted that, for the convenience of description, only a part of the contents, not all of the contents, which are related to the present invention, are shown in the drawings, and unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

Example one

The tire pressure monitoring method of the electric vehicle in the embodiment specifically comprises the following steps:

the wheel speed signal of the front wheel of the electric vehicle is obtained through a wheel speed sensor arranged on the front wheel of the electric vehicle, and the wheel speed signal of the rear wheel of the electric vehicle is obtained through a wheel speed sensor arranged on the rear wheel of the electric vehicle.

And transmitting the wheel speed signal of the front wheel of the electric vehicle and the wheel speed signal of the rear wheel of the electric vehicle to a processing unit.

The signal processing unit processes the received wheel speed signal based on a frequency domain method and a wheel speed comparison method, and judges whether the tire pressure of front and rear wheels of the electric vehicle is normal or not.

Specifically, the wheel speed sensor mounted on the rear wheel of the electric vehicle is mounted inside the rear wheel motor of the electric vehicle in the present embodiment, but is not limited thereto.

Specifically, in this embodiment, the processing the wheel speed signal based on the frequency method specifically includes: firstly, the tyre is simplified into a spring-damper system; secondly, establishing a natural frequency identification model; then, estimating the natural frequency of the tire; finally, estimating the tire pressure state of the tire; wherein the identification of the natural frequency of the tire is realized by a frequency method. It should be noted that the frequency domain method in this embodiment refers to an algorithm for converting a wheel speed signal from a time domain signal to a frequency domain signal, and the algorithm includes, but is not limited to, fast fourier transform, wavelet transform, and auto-regression model, and in this embodiment, a frequency domain analysis may also be performed on the wheel speed signal by using a parametric model spectrum estimation model such as an MA model, an ARMA model, a PRONY index model, and the like.

Specifically, in this embodiment, the wheel speed signal received is processed based on a wheel speed comparison method, which specifically includes: firstly, calibrating the wheel speeds of front wheels and rear wheels under the condition of normal tire pressure of the front wheels and the rear wheels of the electric vehicle by collecting the wheel speed signals of the front wheels of the electric vehicle and the wheel speed signals of the rear wheels of the electric vehicle within set time; secondly, when the tire is under-pressure, the wheel rotational speed can become fast principle, and when the tire was under-pressure promptly, the wheel hall signal value that the instrument in a certain period of time collected can increase, so, the wheel hall signal value that will collect compares with the calibration value, surpasss behind the threshold value of settlement, can judge this wheel tire under-pressure.

Specifically, the wheel speed sensor in the present embodiment may be an active or passive speed sensor, including but not limited to a hall wheel speed sensor, a magneto-electric wheel speed sensor, a photo-electric wheel speed sensor, and a magneto-resistive element wheel speed sensor. In a specific application, the wheel speed sensor is preferably a Hall wheel speed sensor.

Specifically, in this embodiment, the transmission modes of the signals for transmitting the wheel speed signals of the front wheel of the electric vehicle and the wheel speed signals of the rear wheel of the electric vehicle to the processing unit include, but are not limited to, RS-485 bus communication, CAN bus communication, Lin bus communication, RS-232 bus communication, Flexray communication, bluetooth communication, Wi-Fi communication, and USB communication.

Specifically, in this embodiment, the signal processing unit includes, but is not limited to, a single chip, a controller, a central control unit, an MCU, and an ECU inside the electric vehicle instrument, which can process wheel speed signals. In specific application, the signal processing unit preferably adopts a single chip microcomputer in an electric vehicle instrument.

Specifically, in this embodiment, the method for monitoring tire pressure of an electric vehicle further includes: the tire pressure monitoring function is started and closed through a switch or an electric vehicle instrument. Specifically, when the electric motor car tire pressure is unusual in this embodiment when the suggestion of electric motor car instrument, the accessible speaker is reported to the police and is indicateed the rider, lets the rider in time handle.

In specific application, as shown in fig. 1, fig. 1 is a schematic flow chart of an electric vehicle tire pressure monitoring method provided by an embodiment of the present invention, in the diagram, an algorithm i refers to a method for processing a wheel speed signal based on a frequency method, and an algorithm ii refers to a method for processing a received wheel speed signal based on a wheel speed comparison method. As shown in fig. 2, fig. 2 is a schematic diagram of frequency-amplitude values of an electric vehicle when the tire pressure is normal or abnormal according to an embodiment of the present invention.

Example two

The embodiment discloses an electric vehicle tire pressure monitoring system applying the electric vehicle tire pressure monitoring method provided by the first embodiment, and the system comprises: the device comprises a wheel speed sensor arranged on the front wheel of the electric vehicle, a wheel speed sensor arranged on the rear wheel and a processing unit; the wheel speed sensor arranged on the front wheel of the electric vehicle is used for acquiring a wheel speed signal of the front wheel of the electric vehicle; the wheel speed sensor arranged on the rear wheel of the electric vehicle is used for acquiring a wheel speed signal of the rear wheel of the electric vehicle; the processing unit is used for processing the received wheel speed signals based on a frequency domain method and a wheel speed comparison method and judging whether the tire pressures of the front wheel and the rear wheel of the electric vehicle are normal or not.

Specifically, the wheel speed sensor mounted on the rear wheel of the electric vehicle is mounted inside the rear wheel motor of the electric vehicle in the present embodiment, but is not limited thereto. Specifically, in this embodiment, the processing unit processes the wheel speed signal based on a frequency method, and specifically includes: firstly, the tyre is simplified into a spring-damper system; secondly, establishing a natural frequency identification model; then, estimating the natural frequency of the tire; finally, estimating the tire pressure state of the tire; wherein the identification of the natural frequency of the tire is realized by a frequency method. It should be noted that the frequency domain method in this embodiment refers to an algorithm for converting a wheel speed signal from a time domain signal to a frequency domain signal, and the algorithm includes, but is not limited to, fast fourier transform, wavelet transform, and auto-regression model, and in this embodiment, a frequency domain analysis may also be performed on the wheel speed signal by using a parametric model spectrum estimation model such as an MA model, an ARMA model, a PRONY index model, and the like.

Specifically, in this embodiment, the processing unit processes the received wheel speed signal based on a wheel speed comparison method, which specifically includes: firstly, calibrating the wheel speeds of front wheels and rear wheels under the condition of normal tire pressure of the front wheels and the rear wheels of the electric vehicle by collecting the wheel speed signals of the front wheels of the electric vehicle and the wheel speed signals of the rear wheels of the electric vehicle within set time; secondly, when the tire is under-pressure, the wheel rotational speed can become fast principle, and when the tire was under-pressure promptly, the wheel hall signal value that the instrument in a certain period of time collected can increase, so, the wheel hall signal value that will collect compares with the calibration value, surpasss behind the threshold value of settlement, can judge this wheel tire under-pressure.

Specifically, the wheel speed sensor in the present embodiment may be an active or passive speed sensor, including but not limited to a hall wheel speed sensor, a magneto-electric wheel speed sensor, a photo-electric wheel speed sensor, and a magneto-resistive element wheel speed sensor. In a specific application, the wheel speed sensor is preferably a Hall wheel speed sensor.

Specifically, in this embodiment, the transmission modes of the signals transmitted to the processing unit by the wheel speed signals of the front wheel of the electric vehicle and the wheel speed signals of the rear wheel of the electric vehicle include, but are not limited to, RS-485 bus communication, CAN bus communication, Lin bus communication, RS-232 bus communication, Flexray communication, bluetooth communication, Wi-Fi communication, and USB communication. Specifically, in this embodiment, the signal processing unit includes, but is not limited to, a single chip, a controller, a central control unit, an MCU, and an ECU inside the electric vehicle instrument, which can process wheel speed signals. In specific application, the signal processing unit preferably adopts a single chip microcomputer in an electric vehicle instrument.

Specifically, in this embodiment, the system may turn on and off the tire pressure monitoring function through a switch or an electric vehicle meter. Specifically, when the electric motor car tire pressure is unusual in this embodiment when the suggestion of electric motor car instrument, the accessible speaker is reported to the police and is indicateed the rider, lets the rider in time handle.

According to the technical scheme, the wheel speed signals are processed and calibrated in a mode of combining a frequency domain method and a wheel speed comparison method, whether the tire pressure of the electric vehicle is normal or not is monitored, repeated correction is conducted before alarming to the maximum extent, the accuracy rate is effectively improved, and the false alarm rate is reduced. According to the invention, when the tire pressure of the electric vehicle is lower than the set threshold value, a rider is warned, the riding safety of the electric vehicle is improved, the occurrence probability of accidents is reduced, and the tire wear aggravation and the mileage reduction caused by the pressure loss of the tire are avoided. Compared with a direct tire pressure monitoring scheme for measuring the tire pressure by adopting a tire pressure monitoring chip, the invention reduces the dependence on the tire pressure monitoring chip of foreign manufacturers, greatly reduces the cost, enhances the commercial value of the application of the tire pressure monitoring function in the electric vehicle industry, and promotes the progress of the safety of the electric vehicle industry.

It will be understood by those skilled in the art that all or part of the above embodiments may be implemented by the computer program to instruct the relevant hardware, and the program may be stored in a computer readable storage medium, and when executed, may include the procedures of the embodiments of the methods as described above. The storage medium may be a magnetic disk, an optical disk, a read-only memory or a random access memory.

It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.