Description:FIELD OF INVENTION
The present invention is related to automotive vehicle electronics and generally related to method to assist in stability control of an electric vehicle under a wheel-slip condition.

BACKGROUND

For the purpose of locomotion, we need vehicles that not only reduce the time but also work more efficiently. With advanced technological and scientific improvements, there is a requirement for green vehicles which do not pollute the environment and work better. In order to cater to user demands the electric vehicles are designed with various technologies where the innovation comes with safety features also. In the conventional type of vehicles which are Internal combustion engine powered, they come up with a clutch that triggers the powertrain system. For these conventional types where the design is limited to External ABS (Anti-Lock Braking System) that uses numerous sensors which are helpful in the detection of wheel speed when the rotating wheel is going to get locked. It helps in determining the pressure of the brakes and stops the wheel from getting locked. when there is a slippery surface where the wheel is exposed to such conditions.

In the conventional tracking control system, the communication happens between the ABS and Vehicle Control Unit (VCU). In most of the cases as the VCU is an integral part of the vehicle and ABS unit is not an integral part or may be an add-on unit of the vehicle, the communication between the VCU and ABS unit takes up more time and as a result, the response towards any uncontrol event like wheel- slip, the response towards the similar incident is delayed.

PROBLEM TO BE SOLVED BY INVENTION

In the conventional powertrain for electric vehicles when a user is driving a vehicle and accelerates the vehicle, suddenly if the vehicle comes across a slippery surface or wheel-slip condition, then due to loss in friction the wheel and the motor rotates at higher RPM (Revolutions Per Minute) in comparison to the actual movement of the vehicle. At this moment the vehicle becomes uncontrollable as the VCU has all the data regarding the motor speed and actual wheel speed, as the VCU already has all the dynamic data related to the wheel speed and the motor speed, the VCU communicates to the ABS unit that the wheel slip has happened. As ABS belongs to an non-integral part of the vehicle, the communication of the information requires high time. This increases concern regarding the safety of the rider and due to high communication time, the response from the ABS unit may get delayed. Therefore, the primary objective of the present invention is to provide a system and a method of working of the system for assisting in the stability control of the electric vehicle that can establish faster communication with the VCU and can assist in controlling the vehicle under wheel-slip condition.

Moreover, the electric vehicle manufacturing companies may come up the problem by providing an ABS unit as an integral part of the system that can establish communication with the VCU in a faster way. But this will increase the manufacturing cost of the vehicle as the manufacturing of an ABS unit and implementing it as an integral part of the vehicle is a costly procedure. Therefore, another objective of the present invention is to provide a cost-effective system and method of working of the system to assist the stability control of the electric vehicle.

The above-mentioned shortcomings, disadvantages and problems are addressed herein, and which will be understood by reading and studying the following specification.

BRIEF DESCRIPTION OF THE INVENTION

As per the current invention, the present invention discloses a method to assist in stability control of an electric vehicle under a wheel-slip condition, the method comprises of detecting a first speed of the electric vehicle by a speed detection sensor and detecting a first rotational speed of a drive motor of the electric vehicle by a rotational sensor. The said detection of the first speed of the electric vehicle and the first rotational speed of the drive motor are received by an electronic controller from the speed detection sensor and the rotational sensor. Subsequently, the second speed of the electric vehicle is detected by the speed detection sensor and a second rotational speed of a drive motor of the electric vehicle is detected by the rotational sensor. The detected second speed of the electric vehicle and the second rotational speed of the drive motor are received by the electronic controller from the speed detection sensor and the rotational sensor. Moreover, the difference between the first speed and the second speed of the electric vehicle is determined by the electronic controller. Also, the difference between the first rotational speed and the second rotational speed of the drive motor of the electric vehicle is determined by the electronic controller. Thereafter, the determined difference of the detected speed are mapped with a predetermined rotational speed of the electric vehicle by the electronic controller. Also, the predetermined rotational speed is compared with the mapped detected speed with the determined difference of the rotational speed of the drive motor by the electronic controller. Upon detecting an exponential increase in the determined difference of the rotational speed in comparison with the predetermined rotational speed of the drive motor, the electronic controller commands a motor controller to reduce an amount of current transmitted to the drive motor. Further, the motor controller reduce the amount of the current transmitted to the drive motor based on the received command from the electronic controller.

As per the first embodiment of the present invention, wherein commanding the motor controller to reduce the amount of current transmitted to the drive motor may comprise of commanding the motor controller to reduce the amount of current transmitted to the motor controller to zero by the electronic controller. Subsequently, reducing the transmission of current transmitted to the drive motor by the motor controller to zero.

As per the second embodiment of the method in the present invention, wherein commanding the motor controller to reduce the amount of current transmitted to the drive motor may comprise commanding the motor controller to reduce an input received from a throttle operated by the user of the electric vehicle to a lower amount by the electronic controller. Subsequently, reducing the input received from the throttle to a lower amount by the motor controller. Thereafter, transmitting a lower amount of current as per the reduced input of the throttle to the drive motor.

As per the third embodiment of the present invention, wherein commanding the motor controller to reduce the amount of current transmitted to the drive motor may comprise commanding the motor controller to reduce an input received from a throttle operated by the user of the electric vehicle to zero by the electronic controller. Thereafter, reducing the input received from the throttle to zero by the motor controller.

As per another feature of the current invention, the present invention discloses a system to assist in stability control of an electric vehicle under a wheel-slip condition, wherein the system comprises of a speed detection sensor configured to detect a first speed and a second speed of the electric vehicle and a rotational sensor configured to detect a first rotational speed and a second rotational speed of a drive motor of the electric vehicle. Moreover, the system comprises an electronic controller to receive the detected first speed, second speed of the electric vehicle and the first rotational speed, the second rotational speed of the drive motor from the speed detection sensor and the rotational sensor. The electronic controller determines a difference between the first speed and the second speed of the electric vehicle, the said electronic controller is configured to determine a difference between the first rotational speed and the second rotational speed. The electronic controller is also configured to map the determined difference of the detected speed with a predetermined rotational speed of the electric vehicle. Moreover, the electronic controller also compares the predetermined rotational speed as per the mapped detected speed with the determined difference of the rotational speed of the drive motor. Upon detecting an exponential increase in the determined difference of the rotational speed in comparison with the predetermined rotational speed of the drive motor, the electronic controller commands a motor controller to reduce an amount of current transmitted to the drive motor also the motor controller reduces the amount of the current transmitted to the drive motor based on the received command from the electronic controller.

As per the fourth embodiment of the present invention, the system also comprises a wheel operably coupled to the motor through a powertrain system.

As per the fifth embodiment of the present invention, the system includes an anti-lock braking system (ABS) configured to communicate with the electronic controller to control a torque applied on the wheel of the electric vehicle.

As per the sixth embodiment of the present invention, the electronic controller commands the motor controller to reduce the amount of current through a Communication Channel.

As per the seventh embodiment of the present invention, the electronic controller is a vehicle control unit.
LIST OF FIGURES:-
The disclosure will be described and explained with additional specificity and detail with the accompanying figures in which:
FIGURE 1 is a schematic representation of the system to assist in stability control of an electric vehicle under a wheel-slip condition.
FIGURE 2 is a schematic representation of the method to assist in stability control of an electric vehicle under a wheel-slip condition.
Further, those skilled in the art will appreciate that elements in the figures are illustrated for simplicity and may not have necessarily been drawn to scale. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the figures by conventional symbols, and the figures may show only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the figures with details that will be readily apparent to those skilled in the art having the benefit of the description herein.
DETAILED DESCRIPTION OF THE INVENTION
For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the figures and specific language will be used to describe them. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Such alterations and further modifications in the illustrated system, and such further applications of the principles of the invention as would normally occur to those skilled in the art are to be construed as being within the scope of the present invention.
It will be understood by those skilled in the art that the foregoing general description and the following detailed description are exemplary and explanatory of the invention and are not intended to be restrictive thereof.
The terms “comprises”, "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process or method that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such a process or method. Similarly, one or more devices or subsystems or elements or structures or components preceded by "comprises... a'' does not, without more constraints, preclude the existence of other devices, sub-systems, elements, structures, components, additional devices, additional sub-systems, additional elements, additional structures or additional components. Appearances of the phrase "in an embodiment", "in another embodiment" and similar language throughout this specification may, but not necessarily do, all refer to the same embodiment.
Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention belongs. The system, methods, and examples provided herein are only illustrative and not intended to be limiting.
Embodiments of the present invention will be described below in detail with reference to the accompanying figures.
Figure 1 illustrates a system to assist in stability control of an electric vehicle (10) under a wheel-slip condition. The figure discloses a speed detection sensor (101) for detecting a first speed and a second speed of the electric vehicle (10). The Speed detection sensor (101) is operably configured to an electronic controller (103). The system also includes a rotational sensor (1021) for detecting a first rotational speed and a second rotation speed of a drive motor (102) of the electric vehicle (10). The rotational sensor (1021) is also operably configured to the electronic controller (103). As illustrated in figure 1, the rotational sensor (1021) is located in the drive motor (102). However, it is obvious to a person skilled in the art that the location of the positioning of the rotational sensor (1021) may be different. It may be such as bot not limited to, outside the drive motor (102), near a rotor of the motor and like so. Moreover, the electronic controller (103) is configured to determine the difference between the different speeds and map them to predetermined data. The electronic controller (103) is operably configured with a motor controller (104). The electronic controller (103) may have a communication channel (109) with the Motor controller (104) to transmit information such as commanding the motor controller (104) whether to run or stop the drive motor (102).
A wheel-slip condition is a condition or scenario wherein the electric vehicle (10) comes in contact with a slippery surface. It is obvious for a person skilled in the art that the slippery surface may include such as but not limited to oily surface, minor granular particles that assist in lowering down friction of the surface, and like so. The presence of some similar type of particles makes the surface or the way of the electric vehicle (10) slippery and the electric vehicle (10) undergoes wheel-slip condition.
Figure 2 illustrates a schematic representation of the method to assist in the stability control of the electric vehicle (10) under wheel-slip conditions. The illustration of figure 2 is disclosed in the below paragraph.
In the present disclosure, the method comprises of detection of a first speed of the electric vehicle (10) by a speed detection sensor (101) and the detection of a first rotational speed of a drive motor (102) of the electric vehicle (10) by a rotational sensor (1021). After detection of the first rotational speed of drive motor (102) of the electric vehicle (10) by a rotational sensor (1021) the said detected signal is transmitted. The detected first speed of the electric vehicle (10) and the first rotational speed of the drive motor (102) are received by an electronic controller (103) from the speed detection sensor (101) and the rotational sensor (1021). Subsequently, the speed detection sensor (101) detects a second speed of the electric vehicle and the rotational sensor (1021) detects a second speed of the drive motor (102). After detection the detected speeds are transmitted. The detected second speed of the electric vehicle (10) and the second rotational speed of the drive motor (102) are received by the electronic controller (103) from the speed detection sensor (101) and the rotational sensor(1021). The difference between the first speed and the second speed of the electric vehicle (10) is determined by the electronic controller (103). Similarly, the difference between the first rotational speed and the second rotational speed of the drive motor (102) of the electric vehicle(10) is also determined by the electronic controller (103). The said determined difference of the detected speed is mapped with a predetermined rotational speed of the electric vehicle (10) by the electronic controller (103). For better comparison of the predetermined rotational speed as per the mapped detected speed with the determined difference of the rotational speed of the drive motor (102) is performed by the electronic controller (103). Thereafter, upon detecting an exponential increase in the determined difference of the rotational speed in comparison with the predetermined rotational speed of the drive motor (102) a motor controller (104) commands to reduce an amount of current transmitted to the drive motor (102) by the electronic controller (103), and based on the received command from the electronic controller (103) the amount of the current transmitted to the drive motor (102) is reduced by the motor controller (104)

As per the first embodiment of the present invention, commanding the motor controller (104) to reduce the amount of current transmitted to the drive motor (102) may include commanding the motor controller (104) to reduce the amount of current transmitted to the motor controller (104) to zero by the electronic controller (103). Further, the transmission of current transmitted to the drive motor (102) may be reduced to zero by the motor controller (104).

As per the second embodiment of the present invention, commanding the motor controller (104) to reduce the amount of current transmitted to the drive motor (102) may include commanding the motor controller (104) to reduce an input received from a throttle (105) operated by the user of the electric vehicle (10) to a lower amount by the electronic controller (103). The input received from the throttle (105) is reduced to a lower amount by the motor controller (104). Thereafter, a lower amount of current is transmitted to the drive motor (102) as per the reduced input of the throttle (105).

As per the third embodiment of the present invention, commanding the motor controller (104) to reduce the amount of current transmitted to the drive motor (102) may include commanding the motor controller (104) to reduce an input received from a throttle (105) operated by the user of the electric vehicle (10) to zero by the electronic controller (103). Thereafter, reducing the input received from the throttle (105) to zero is done by the motor controller (104). Once the electronic controller (103) detects the exponential increase in the determined difference of the rotational speed in comparison with the predetermined rotational speed of the drive motor (102) then depending on the determined difference and its effect over the stability of the electric vehicle (10), the electronic controller (103) may command the motor controller (104) to reduce the transmission of the current transmitted to the drive motor (102) to a lower value or reduce the transmission of the current to zero as per the stability requirement of the electric vehicle (10).

In another exemplary embodiment, the present invention discloses a system to assist in the stability control of the electric vehicle (10) under a wheel-slip condition, wherein the system comprises a speed detection sensor (101) and a rotational sensor (1021) wherein the speed detection sensor (101) is configured to detect a first speed and a second speed of the electric vehicle (10) while the rotational sensor (1021) is configured to detect a first rotational speed and a second rotational speed of a drive motor (102) of the electric vehicle (10). Moreover, the system comprises an electronic controller (103) configured to receive the detected first speed and second speed of the electric vehicle (10) from the speed detection sensor (101), on the other hand, the electronic controller (103) is also configured to receive the first rotational speed and the second rotational speed of the drive motor (102) the rotational sensor (1021). The electronic controller (103) also determines a difference between the first speed and the second speed of the electric vehicle (10), the said electronic controller (103) is configured to determine a difference between the first rotational speed and the second rotational speed. Moreover, the electronic controller (103) is capable to map the determined difference of the detected speed with a predetermined rotational speed of the electric vehicle (10) and compares the predetermined rotational speed as per the mapped detected speed with the determined difference of the rotational speed of the drive motor (102). Thereafter, upon detecting an exponential increase in the determined difference of the rotational speed in comparison with the predetermined rotational speed of the drive motor (102). Also, the electronic controller (103) commands a motor controller (104) to reduce an amount of current transmitted to the drive motor (102). Further, the system includes the motor controller (104) capable of reducing the amount of current transmitted to the drive motor (102) based on the received command from the electronic controller (103).

As per the fourth embodiment of the present invention, the system comprises a wheel (106) operably coupled to the drive motor (102) through a powertrain system (107).

As per the fifth embodiment of the present invention, the system includes an anti-lock braking system (ABS) (108) configured to communicate with the electronic controller (103) to control a torque applied on the wheel (106) of the electric vehicle (10).

As per the sixth embodiment of the present invention, the electronic controller (103) and the motor controller (104) include an input/output interface for communicating with other components included in the electric vehicle (10) over one or more wired or wireless communication channels or networks. The electronic controller (103) commands the motor controller (104) to reduce the amount of current through a Communication channel (109).

As per the seventh embodiment of the present invention, the electronic controller (103) is a vehicle control unit.

From the above discussion, when the rider is driving the electric vehicle (10) at a particular speed, the rider has to accelerate the electric vehicle (10) to maintain the momentum of the electric vehicle (10). In a scenario, wherein the electric vehicle (10) enters a wheel-slip condition, the wheel (106) may experience a higher rotation in comparison to the actual dynamic speed of the electric vehicle (10). As in a gearless electric vehicle, a rotor of the drive motor (102) is directly connected to the wheel (105) without any gear reduction so the speed of the rotation of the wheel (105) is equal to the speed of the rotation of the rotor. Moreover, as the electronic controller (103) of the electric vehicle (10) receives all the data like vehicle speed, drive motor rotation and like so from the components directly and doesn’t has to depend on the non-integral components of the electric vehicle (10) such as the ABS (108) unit, the electronic control initiates the assist the stability control of the electric vehicle (10) and as a result, the torque implementation on the drive motor (102) is lowered down to control the electric vehicle (10).

In an exemplary embodiment, the electronic controller (103) in the electric vehicle (10) controls and regulates the different operations of the electric vehicle (10) such as but not limited to receiving vehicle dynamic speed, receiving motor rotational speed and like so. Moreover, the electronic controller (103) may include an electronic processor such as a microprocessor, an application-specific integrated circuit, a non-transitory computer-readable memory for storing limits or other predetermined parameters for assisting the stability control of the electric vehicle (10). The electronic controller (103) may include a table or a graphical representation to map the difference in the detected speed of the electric vehicle (10) with a predetermined rotational speed of the electric vehicle (10) as per the determined difference. Depending upon the exponential increase in the determined difference of the rotational speed in comparison with the predetermined rotational speed of the drive motor (102), the electronic controller (103) commands the motor controller (104) to reduce the amount of current. Consecutively, this reduces the RPM (Revolutions Per Minute) of the drive motor (102) to bring back the stability of the electric vehicle (10).
While specific language has been used to describe the invention, any limitations arising on account of the same are not intended. As would be apparent to a person skilled in the art, various working modifications may be made to the method in order to implement the inventive concept as taught herein.
The figures and the foregoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment. Also, those acts that are not dependent on other acts may be performed in parallel with the other acts. The scope of embodiments is by no means limited by these specific examples.
FURTHER ADVANTAGES OF THE INVENTION:
So, the present invention provides a system and a method of working of the system for assisting in the stability control of the electric vehicle (10) that can establish faster communication with the electronic control unit and can assist in controlling the electric vehicle (10) under wheel-slip conditions. The system and method as disclosed by the present invention establishes a cost-effective system and method of working of the system to assist the stability control of the electric vehicle (10). As per the discussed implementation of the system, the electronic controller (103) does not depend on any non-integral component such as ABS (108), so the electronic controller (103) can itself initiate the assistance of the stability control without any dependency on external components. As a result, the response time is comparatively less compared to the response time of the ABS (108) unit working in combination with the electronic control unit of the electric vehicle (10). Consecutively, with low response time, the present invention improves the safety of the electric vehicle (10) and a rider can get control of the uncontrolled stability of the electric vehicle (10) sooner. Additionally, the present invention prevents the rider from slipping due to the uncontrolled stability of the electric vehicle (10). Further, as the present invention does not depend on the ABS (108) unit, so the system can be easily implemented on the electric vehicle (10) irrespective of the presence of the ABS (108) unit.
REFERENCE TABLE

S. No. Name Reference Numerals
1 Electric vehicle 10
2 Speed detection sensor 101
3 Drive motor 102
4 Rotational sensor 1021
5 Electronic controller 103
6 Motor controller 104
7 Throttle 105
8 Wheel 106
9 Powertrain system 107
10 Anti-lock Braking system (ABS) 108
11 Communication Channel 109
, Claims:CLAIMS:
We claim:
1. A method to assist in stability control of an electric vehicle (10) under a wheel-slip condition, the method comprises:
detecting a first speed of the electric vehicle (10) by a speed detection sensor (101);
detecting a first rotational speed of a drive motor (102) of the electric vehicle (10) by a rotational sensor (1021);
receiving the detected first speed of the electric vehicle (10) and the first rotational speed of the drive motor (102) by an electronic controller (103) from the speed detection sensor (101) and the rotational sensor (1021);
detecting a second speed of the electric vehicle (10) by the speed detection sensor (101);
detecting a second rotational speed of a drive motor (102) of the electric vehicle (10) by the rotational sensor (1021);
receiving the detected second speed of the electric vehicle (10) and the second rotational speed of the drive motor (102) by the electronic controller (103) from the speed detection sensor (101) and the rotational sensor (1021);
determining a difference between the first speed and the second speed of the electric vehicle (10) by the electronic controller (103);
determining a difference between the first rotational speed and the second rotational speed of the drive motor (102) of the electric vehicle (10) by the electronic controller (103);
mapping the determined difference of the detected speed with a predetermined rotational speed of the electric vehicle (10) by the electronic controller (103);
comparing the predetermined rotational speed as per the mapped detected speed with the determined difference of the rotational speed of the drive motor (102) by the electronic controller (103);
upon detecting an exponential increase in the determined difference of the rotational speed in comparison with the predetermined rotational speed of the drive motor (102),
commanding a motor controller (104) to reduce an amount of current transmitted to the drive motor (102) by the electronic controller (103),
reducing the amount of the current transmitted to the drive motor (102) by the motor controller (104) based on the received command from the electronic controller (103).
2. The method as claimed in claim 1, wherein commanding the motor controller (104) to reduce the amount of current transmitted to the drive motor (102) may comprise:
commanding the motor controller to reduce the amount of current transmitted to the motor controller (104) to zero by the electronic controller (103);
reducing the transmission of current transmitted to the drive motor (102) by the motor controller (104) to zero.
3. The method as claimed in claim 1, wherein commanding the motor controller (104) to reduce the amount of current transmitted to the drive motor (102) may comprise:
commanding the motor controller (104) to reduce an input received from a throttle (105) operated by the user of the electric vehicle (10) to a lower amount by the electronic controller (103);
reducing the input received from the throttle (105) to a lower amount by the motor controller (104);
transmitting a lower amount of current as per the reduced input of the throttle (105) to the drive motor (102).
4. The method as claimed in claim 1, wherein commanding the motor controller (104) to reduce the amount of current transmitted to the drive motor (102) may comprise:
commanding the motor controller (104) to reduce an input received from a throttle operated by the user of the electric vehicle (10) to zero by the electronic controller (103);
reducing the input received from the throttle (105) to zero by the motor controller (104).

5. A system to assist in stability control of an electric vehicle (10) under a wheel-slip condition, wherein the system comprises:
a speed detection sensor (101) configured to detect a first speed and a second speed of the electric vehicle (10),
a rotational sensor (1021) configured to detect a first rotational speed and a second rotational speed of a drive motor (102) of the electric vehicle (10),
an electronic controller (103) to receive the detected first speed, second speed of the electric vehicle (10) and the first rotational speed, the second rotational speed of the drive motor (102) from the speed detection sensor (101) and the rotational sensor (1021),
the electronic controller (103) determines a difference between the first speed and the second speed of the electric vehicle (10), the said electronic controller (103) is configured to determine a difference between the first rotational speed and the second rotational speed,
the electronic controller (103) is configured to map the determined difference of the detected speed with a predetermined rotational speed of the electric vehicle (10),
the electronic controller (103) compares the predetermined rotational speed as per the mapped detected speed with the determined difference of the rotational speed of the drive motor (102),
upon detecting an exponential increase in the determined difference of the rotational speed in comparison with the predetermined rotational speed of the drive motor (102),
the electronic controller (103) commands a motor controller (104) to reduce an amount of current transmitted to the drive motor (102),
the motor controller (104) reduces the amount of the current transmitted to the drive motor (102) based on the received command from the electronic controller (103).
6. The system as claimed in claim 5, wherein the system comprises a wheel (105) operably coupled to the drive motor (102) through a powertrain system (107).

7. The system as claimed in claim 5, wherein the system includes an anti-lock braking system (ABS) (108) configured to communicate with the electronic controller (103) to control a torque applied on the wheel (105) of the electric vehicle (10).

8. The system as claimed in claim 5, wherein the electronic controller commands the motor controller (104) to reduce the amount of current through a Communication Channel (109).

9. The system as claimed in claim 5, wherein the electronic controller (103) is a vehicle control unit.

Dated this the 21st day of July 2023