GB2566500A

GB2566500A - Spin-control system for electrical vehicles

Info

Publication number: GB2566500A
Application number: GB1714894.1A
Authority: GB
Inventors: lam Albert
Original assignee: Detroit Electric EV Technologies Zhejiang Ltd
Current assignee: Detroit Electric EV Technologies Zhejiang Ltd
Priority date: 2017-09-15
Filing date: 2017-09-15
Publication date: 2019-03-20
Anticipated expiration: 2037-09-15
Also published as: GB201714894D0; GB2566500B

Abstract

A spin-control system 100 for an electrical vehicle 102 includes a vehicle frame 104, a battery 114, a power controller 116 for controlling electrical power flow between the battery and an electrical motor arrangement 120A-D. The front wheels 106, 108 are driven by in hub motors 120A/B and the rear wheels 110, 112 are driven by motors 120C/D implemented as sprung elements with each motor being independently controllable. Angular sensor 118 senses an angular orientation of the vehicle to provide an angle and/or angular turning rate signal for the spin-control system. When the angle and/or angular turning rate signal exceeds a threshold value the system applies a differential torque to at least one of the left and right wheels which may be adapted depending on vehicle speed. Torque sensors may be coupled to the rear wheels and an indicator may indicate when the angular turning rate exceeds the threshold vale.

Description

SPIN-CONTROL SYSTEM FOR ELECTRICAL VEHICLES

TECHNICAL FIELD

The present disclosure generally relates to traction control in electrical vehicles, and specifically to a spin-control system for an electrical vehicle.

BACKGROUND

Recently, there has been an increased interest in manufacture of electrical vehicles. Typically, such interest has focused on dealing with various issues, for example, reducing emissions of greenhouse gas, coping with increasing fuel oil prices by reducing use of oil products, and so forth. Furthermore, contemporary electrical vehicles include performance vehicles which support powerful electrical motors and provide brisk accelerations when in operation. Generally, the performance vehicles rely on a rear wheel drive (RWD), because such rear wheel drive (RWD) it is capable of providing a better initial acceleration by transferring a weight to a rear portion of a given electrical vehicle. Moreover, providing high torque to front wheels of an electrical vehicle while simultaneously also accommodating for steering front wheels is, from an engineering perspective, difficult to achieve.

However, use of such performance vehicles involves various difficulties. Firstly, such performance vehicles are more susceptible to spinning due to loss of traction on slippery surfaces, such as wet or muddy roads, black ice or loose gravel. Secondly, a driver of such performance vehicle has to apply breaks and operate a steering to control the direction traversed by the vehicle and recover from a spin. Consequently, the driver is solely dependent on his/her driving skills, experience, and perception to operate such a vehicle while the vehicle is in a spinning condition. Furthermore, even with modern traction control capabilities, such vehicles remain prone to spinning out of control due to loss of traction. Thus, use of such vehicles may not be preferred in unfavorable conditions, for example when driving in aforementioned slippery surfaces and at high speeds.

Therefore, in light of the foregoing discussion, there exists a need to address, for example to overcome, the aforementioned drawbacks associated with the conventional spin-control system of electrical vehicles.

SUMMARY

The present disclosure seeks to provide an improved spin-control system for an electrical vehicle.

According to a first aspect, an embodiment of the present disclosure provides a spin-control system for an electrical vehicle, wherein the electrical vehicle comprises a vehicle frame arrangement, a battery arrangement for storing energy, a power control arrangement for controlling an electrical power flow between the battery arrangement and an electrical motor arrangement, wherein the electrical motor arrangement is operable to drive a pair of front wheels and a pair of rear wheels of the electrical vehicle; characterized in that:

(i) the electrical motor arrangement includes four electrical motors for applying in operation torque to the pair of front wheels and rear wheels; wherein the electrical motors are mutually independently controllable by the power control arrangement of the electric vehicle; wherein motors associated with the pair of front wheels are implemented as in-hub electrical motors; and wherein motors associated with the pair of rear wheels are implemented as a sprung element of the vehicle frame arrangement and coupled via a coupling arrangement to their corresponding wheels;

(ii) the spin-control system comprises an angular sensor for sensing an angular orientation of the electrical vehicle to provide an angle and/or angular turning rate signal for the spin-control system; and (iii) the spin-control system is operable to apply differential torque between at least one wheel located on a right-side and at least one wheel located on a left-side of the electrical vehicle when the electrical vehicle executes turning maneuvers in operation and when the angle and/or angular turning rate signal of the angular sensor exceeds a threshold value.

The present disclosure seeks to provide an improved spin-control system for providing an efficient spin-control of electrical vehicles, especially on slippery (slick) surfaces, such as wet or muddy roads, black ice or loose gravel; the spin-control is performed efficiently based on the sensing of the angular sensor.

It will be appreciated that features of the present disclosure are susceptible to being combined in various combinations without departing from the scope of the present disclosure as defined by the appended claims.

The present invention is included in the general business context, which aims to substitute vehicles powered by traditional fuels, for example gasoline or diesel, by electric vehicles. In particular, the present invention is intended for use in electric vehicles used within cities, which can be highly beneficial to the local environment due to significant reduction of gaseous emissions as well as significant reduction of noise. Overall environmental benefits can also be significant when electric vehicles are charged from renewable energy sources.

DESCRIPTION OF THE DRAWINGS

The summary above, as well as the following detailed description of illustrative embodiments, is better understood when read in conjunction with the appended drawings. For the purpose of illustrating the present disclosure, exemplary constructions of the disclosure are shown in the drawings. However, the present disclosure is not limited to specific methods and instrumentalities disclosed herein. Moreover, those in the art will understand that the drawings are not to scale. Wherever possible, like elements have been indicated by identical numbers.

Embodiments of the present disclosure will now be described, by way of example only, with reference to the following diagrams wherein:

FIG. 1 is a schematic illustration of a spin-control system for an electrical vehicle, in accordance with an embodiment of the present disclosure.

In the accompanying drawings, an underlined number is employed to represent an item over which the underlined number is positioned or an item to which the underlined number is adjacent. A non-underlined number relates to an item identified by a line linking the non-underlined number to the item. When a number is non-underlined and accompanied by an associated arrow, the non-underlined number is used to identify a general item at which the arrow is pointing.

DESCRIPTION OF EMBODIMENTS

In overview, embodiments of the present disclosure are concerned with a spin-control system for electrical vehicles, and specifically, for both the front and rear wheel driven electrical vehicles.

Referring to FIG. 1, there is shown a schematic illustration of a spincontrol system 100 for an electrical vehicle 102 in accordance with an embodiment of the present disclosure. The electrical vehicle 102 comprise a vehicle frame arrangement 104, a battery arrangement 114 for storing energy, a power control arrangement 116 for controlling an electrical power flow between the battery arrangement 114 and an electrical motor arrangement 120. The electrical motor arrangement 120 is operable to drive a pair of front wheels 106-108 and a pair of rear wheels 110-112 of the electrical vehicle 102. Furthermore, the electrical motor arrangement 120 includes four electrical motors 120A-D for applying in operation torque to the pair of front wheels 106 to 108 and rear wheels 110 toll2, respectively.

Throughout the present disclosure, the term 'spin-controlsystem’ as used herein relates to an arrangement and/or a module that is configured to enable a user to control of one or more operations of a vehicle. The spincontrol system 100 is operable to control the direction in which the electrical vehicle 102 moves. Additionally, the spin-control system 100 is operable to manipulate the operation of the one or more components of the electrical vehicle 102 for manoeuvring the electrical vehicle 102 in a preferred direction.

Throughout the present disclosure, the term 'electrical vehicle’ as used herein relates to a motorized vehicle, such as a car, van, truck or the like, in which an individual, might ride in as a driver and/or a passenger. Furthermore, the vehicle includes a vehicle frame arrangement 104. Optionally, the term 'vehicle frame arrangement' as used herein relates to a body structure of the vehicle that provides a platform on which various parts of the vehicle such as motors, batteries, engines, doors, windshields, sun-visors and so forth, are arranged. Optionally, the vehicle frame arrangement 104 provides a structure of the vehicle cabin. Additionally, the vehicle cabin relates to an interior of the vehicle that allows a driver to be properly supported on a seat for operating the vehicle. It will be appreciated that the driver is an individual that is operating the vehicle. Furthermore, the vehicle frame arrangement 104 includes a plurality of wheels 106 to 112 for supporting the electrical vehicle 102 on a road surface. Additionally, the plurality of wheels 106 to 112 includes a left-side front wheel 106, a right-side front wheel 108, a left-side rear wheel 110, and a right-side rear wheel 112. Consequently, the left-side front wheel 106, and the right-side front wheel 108 form the pair of front wheels for the electrical vehicle 102 and the left-side rear wheel 110, and the right-side rear wheel 112 form the pair of rear wheels for the electrical vehicle 102. Additionally, the leftside front wheel 106 and the left-side rear wheel 110 form the pair of wheels on the left side of the electrical vehicle 102, and the right-side front wheel 108 and the right-side rear wheel 112 form the pair of wheels on the right side of the electrical vehicle 102.

Throughout the present disclosure, the term 'battery arrangement' relates to a group of battery modules arranged in a manner that is operable to provide power to a vehicle (such as the electrical vehicle 102). For example, the battery arrangement 114 employs a plurality of battery modules including Lithium Iron Phosphate gel battery cells. Optionally, the battery arrangement 114 is implemented as a floormounted flat battery unit. Alternatively, the battery arrangement 114 is implemented as an L-shaped battery unit mounted behind seats of the cabin. The battery arrangement 114 is operable to store energy. Furthermore, the battery arrangement 114 is configured to provide electric power to the various components of the electrical vehicle 102, for example, the electrical motors used in the electrical vehicle 102 to propel the electrical vehicle 102.

The electrical vehicle 102 includes a power control arrangement 116 for controlling an electrical power flow between the battery arrangement 114 and an electrical motor arrangement 120. Throughout the present disclosure, the term 'power control arrangement' as used herein relates

Ί to an arrangement and/or a module including programmable and nonprogrammable components that is configured to control the flow of electric power from the battery arrangement 114 and the electrical motor arrangement 120. Furthermore, the power control arrangement 116 is operable to control operation of the electrical motor arrangement 120 (described herein later) by controlling the amount of the power transfer from the battery arrangement 114. Optionally, the power control arrangement 116 comprises electronic components, such as a processer, memory, a network adapter an input means, an output means and so forth. Optionally, the power control arrangement 116 includes devicefunctionality software and/or operating system software configured to execute other application programs for controlling the amount of power transferred to the electrical motor arrangement 120 thereby controlling the operation of the electrical motor arrangement 120. Optionally, the power control arrangement 116 is operated by the driver from a carputer of the electrical vehicle 102.

Throughout the present disclosure, the term 'electrical motor arrangement' as used herein relates to a group of one or more electrical motors organized in a manner that the arrangement is operable to motive power to the one or more wheels of the electrical vehicle 102. Furthermore, the electrical motor arrangement 120 includes a plurality of motors. The electrical motor arrangement 120 includes four electrical motors 120A to 120D for applying in operation torque to the pair of front wheels 106 and 108 and rear wheels 110 and 112, respectively.

Optionally, each of the four electrical motors 120A to 120D that is associated with the pair of front wheels 106 and 108 and the pair of rear wheels 110 and 112, respectively, includes a casing. Furthermore, the casing is operable to accommodate components of the at least one electrical motor, as described herein later. In one example, the casing is implemented as a hollow cylindrical structure that is operable to accommodate the components of the at least one electrical motor. In another example, the casing is implemented as a hollow cylindrical structure including a plurality of portions, for example two semicylindrical halves. In such an instance, the semi-cylindrical halves are operable to be arranged along mutually abutting surface thereof, for example a planar surface thereof, to provide the casing.

Optionally, the each of the four electrical motors 120A to 120D includes a stator mounted on the casing. The stator is a stationary component of the at least one electrical motor. Furthermore, the stator is operable to provide a magnetic field to enable operation of one or more components of the at least one electrical motor (such as a rotor). The stator includes one or more planar, for example radial plate-like, stator elements extending from the casing, wherein each of the one or more planar stator elements includes a central hole. In one example, the one or more planar stator elements are fabricated using fiberglass, carbon fiber or a fiberreinforced composite material. Furthermore, the one or more planar stator elements are attached to an inside of the casing.

Moreover, the at least one electrical motor includes a rotor. The rotor is a rotatable component of the at least one electrical motor that enables to generate torque, for example, for rotating one or more wheels associated with the electrical vehicle. In an embodiment, the rotor is operable to rotate at a maximum rotation rate in a range of 30000 rotations per minute (rpm) to 100000 rotations per minute (rpm). It will be appreciated that such a high rotation rate of the rotor enables a high-speed operation of the at least one electrical motor, and enables the at least one electrical motor to be fabricated in a very compact and light-weight manner.

The rotor includes a rotor shaft that is disposed within the central hole of each of the one or more planar stator elements of the stator. For example, the rotor shaft is implemented as a cylindrical structure that is operable to rotate around an axis (such as an axis passing through center of the cylindrical rotor shaft). Furthermore, the rotor includes one or more planar, for example radial plate-like, rotor elements attached to the rotor shaft. In one example, the one or more planar rotor elements are fabricated using fiberglass carbon fiber or fiber-reinforced composite material. Furthermore, the one or more planar rotor elements are attached to the rotor shaft along the axis thereof.

Moreover, principal planes of the one or more planar stator elements and rotor elements are arranged mutually to abut with a magnetic separation gap therebetween. For example, the one or more planar rotor elements are attached to the rotor shaft such that the one or more planar rotor elements are positioned alternately with the one or more planar stator elements of the stator. In such an instance, it will be appreciated that the one or more planar stator elements do not obstruct the rotation of the rotor as the one or more planar rotor elements of the rotor are disposed in a gap formed by two adjacent planar stator elements. Furthermore, such an arrangement of the one or more planar stator elements and the one or more planar rotor elements enables formation of the magnetic separation gap therebetween. For example, the magnetic separation gap is defined by distance between principal surface planes of the one or more planar stator elements and the one or more planar stator elements (such as, planes passing through center and along flat planes of the one or more planar stator elements and the one or more planar rotor elements). According to an embodiment, the magnetic separation gap is in a range of 0.3 mm to 10 mm, more optionally in a range of 0.5 mm to 5.0 mm. In one example, the magnetic separation gap is 1.0 mm. In another example, the magnetic separation gap is 4.5 mm.

Moreover, the one or more planar stator elements and the one or more planar rotor elements are arranged to have electrical winding coil arrangements disposed thereon. In one example, the one or more planar stator elements are arranged to have electrical winding coil arrangements disposed thereon. Such electrical winding coil arrangements enable to provide the magnetic field to enable the rotation of the rotor. In an embodiment, the electrical winding coil arrangements are implemented using printed circuit board conductive tracks. For example, the one or more planar stator elements is implemented as a printed circuit board that is fabricated using fiberglass. In such an instance, the electrical winding coil arrangements are implemented as copper conductive tracks that are lithographically (for example, using optical lithography) printed or fabricated using lithographically-defined etching processes onto the printed circuit board.

In an example, the one or more planar rotor elements are arranged to have electrical winding coil arrangements disposed thereon. According to an embodiment, the electrical winding coil arrangements are implemented using printed circuit board conductive tracks. For example, the one or more planar rotor elements are implemented as printed circuit boards that are fabricated using fiberglass. In such an instance, the electrical winding coil arrangements are implemented as conductive tracks that are lithographically printed or fabricated using lithographically-defined etching processes onto the printed circuit board. In one example, the printed circuit board includes copper conductive tracks.

The at least one electrical motor includes magnetic bearings coupled to ends of the rotor shaft. For example, the rotor is operable to rotate at high maximum rotation rates, such as, in a range of 30000 rotations per minute (rpm) to 100000 rotations per minute (rpm). In such an instance, the magnetic bearings are operable to prevent physical contact between the rotor shaft and one or more other components of the at least one motor, such as, the one or more planar stator elements. Furthermore, the electrical motor arrangement 120 is devoid of rare-earth permanent magnets for torque generating purposes when in operation; however, the one or more planar stator elements and the one or more planar rotor elements are beneficially provided with paramagnetic cores, for example implemented using ferrite materials and/or laminated ferromagnetic materials (for example, laminate silicon steel sheets as contemporarily employed in electrical transformers). Optionally, the at least one electrical motor includes mechanical bearings. Furthermore, the magnetic bearings are backed up with the mechanical bearings (for example ballrace ball bearing arrangements, or roller ball-race bearing arrangements), in an event that the rotor of the motors is subject to extreme forces in operation that cause the magnetic bearing to bottom out so that mechanical bearing then supports high revolution rates of the rotor under heavy load conditions.

Optionally, at least one electrical motor of the plurality of electrical motors 120A to 120D is coupled to at least one wheel of the plurality of wheels 106 to 112 of the electrical vehicle 102. Specifically, the electrical motor 120A is coupled with left-side front wheel 106, the motor 120B coupled with right-side front wheel 108, the electrical motor 120C coupled with left-side rear wheel 110, and the electrical motor 120D coupled with right-side rear wheel 112. Furthermore, the plurality of electrical motors 120A to 120D acquires electrical power from the battery arrangement 114 to provide a rotational force to the plurality of wheels 106 to 112 to produce a rotational motion therein. Optionally, an output shaft of at least one electrical motor is coupled via a corresponding gear arrangement to wheel axles of the electrical vehicle 102.

The electrical motors 120 A and 120B associated with the pair of front wheels 106 and 108 is implemented as an in-hub electrical motor (commonly known as wheel hub motors, wheel motor, wheel hub drive, hub motor or in-wheel motor). Optionally, the electrical motors 120A and 120B are provided for applying the torque to the two front wheels 106 and 108. Specifically, the electrical motors 120A and 120B are provided at a hub of the front wheels 106 and 108. It will be appreciated that the electrical motors 120A and 120B are incorporated into the hub of the front wheels 106 and 108 and rotate the wheels directly. The electrical motors 120A and 120B are operable to apply, in operation, torque to the corresponding wheels. For example, the electrical motors 120A and 120B are operable to provide in operation torque to the pair of front wheels 106 and 108 when mounted thereupon. Optionally, size of the electrical motors 120A and 120B is relatively smaller than the size of other electrical motors (for example, such as electrical motors 120C and D).

The electrical motors 120C and 120D associated with the pair of rear wheels 110 and 112 are implemented as a sprung element of the vehicle frame arrangement 104 and coupled via a coupling arrangement to its corresponding wheels 110 and 112. Throughout the present disclosure the term sprung element of the vehicle frame arrangement, used herein, relates to an element, mass of which is supported by wheel suspensions. Furthermore, the electrical motors 120C and 120D are mounted on the vehicle frame arrangement 104. Since mass of the vehicle frame arrangement 104 is supported by the wheel suspensions or spring and damper arrangement, the mass of the electrical motors 120C and 120D are supported by the wheel suspensions or spring and damper arrangement. Throughout the present disclosure the term coupling arrangement, used herein, relates to a set of elements configured to transmit the torque generated by the electrical motors 120C and 120D to corresponding wheels 110 and 112. Optionally, the coupling arrangement includes a clutch member and a gear box arrangement. The output shaft of the electrical motors 120C and 120D is coupled to the clutch member. The clutch member is further coupled to a gearbox arrangement, wherein the gearbox arrangement is configured for providing a geared output torque. The gearbox arrangement includes an output shaft for propelling the electrical vehicle

102 when in operation. Furthermore, the plurality of electrical motors 120A to 120D includes an output shaft. Specifically, the output shaft is coupled to a rotor shaft of the plurality of electrical motors 120A to 120D such that the rotational movement of the rotor shaft is transmitted to the output shaft.

The plurality of electrical motors 120A to 120D are mutually independently controllable by the power control arrangement 116 of the electric vehicle 102. Furthermore, the plurality of electrical motors 120A to 120D is mutually independently controllable from the power control arrangement 116 of the electric vehicle 102. The power control arrangement 116 is operable to control the operation of the plurality of electrical motors 120A to 120D mutually independently. For example, the power control arrangement 116 provides different electrical power to each of the plurality of electrical motors 120A to 120D, based on the requirement of the electrical vehicle 102. Furthermore, the power control arrangement 116 of the electrical vehicle 102 is operable to control the torque provided by the plurality of electrical motors 120A to 120D to the wheels 106 to 112. Optionally, the power control arrangement 116 includes a rotor excitation unit and a switching control unit.

Optionally, in this regard, the power control arrangement 116 includes a rotor excitation unit to couple electrical power from a battery arrangement 114 of the electrical vehicle 102 to a resonant inductive power coupling arrangement, wherefrom the electrical power is coupled wirelessly to a rotor of the at least one electrical motor for generating a rotor magnetic field that is operable to interact in operation with a commutated magnetic field of a stator of the at least one electrical motors.

Optionally, in this regard, the power control arrangement 116 includes a switching control unit. Furthermore, the switching control arrangement comprises a plurality of switching elements. Moreover, a negative connection of the rotor excitation arrangement is coupled via phase coils and their respective switches to a negative terminal of the battery arrangement 114. Additionally, the power control arrangement 116 controls the functioning of the plurality of switching elements of the switching arrangement. Furthermore, the plurality of switching elements is beneficially implemented by way of silicon carbide transistors, although other types of solid state switching devices are optionally employed, for example silicon D-MOS power transistors, bipolar transistors, SCR's, thyristors and similar. Silicon carbide transistors are capable of switching large currents in an order of 100 Amperes within nanoseconds, while simultaneously being able to withstand applied potentials up to around 1000 Volts.

The spin-control system 1OO includes an angular sensor 118 for sensing an angular orientation of the electrical vehicle 102 to provide an angle and/or angular turning rate signal for the spin-control system 100: optionally, the angular sensor 118 is implemented as a configuration of angular accelerometers, as a silicon micromachined vibrating gyroscope, an optical fiber gyroscope or similar. The spin-control system 100 is operable to prevent the electrical vehicle 102 from going into a spin due to loss of traction at high speeds and/or slippery (slick) surfaces, such as wet or muddy roads, black ice or loose gravel. The spin-control system 100 relies on the angular sensor 118 for sensing the angular orientation (Θ) of the electrical vehicle 102 about a vertical axis through its center of gravity. Furthermore, based upon the sensed angular orientation (Θ), the spin-control system 100 provides an angle and/or angular turning rate signal which represent the rate of angular rotation of the electrical vehicle 102 about the vertical axis. Additionally, the angle and/or angular turning rate signal, in reference to the speed of the vehicle, indicates whether or not the electrical vehicle 102 is in a condition of excessive spin.

Optionally, for example as aforementioned, the angular sensor 118 is implemented using at least one of a resonating Coriolis sensor, an optical gyroscopic sensor, a ring-laser gyro, a differential accelerometer arrangement or similar. Generally, a gyroscopic sensor senses an angular orientation and/or changes in angular orientation and/or movement with respect to a fixed axis. For example, when the angular sensor 118 includes a resonating Coriolis sensor, the angle and/or angular turning rate is detected by a vibrating planar ring mounted on a flexible frame. The resonating Coriolis sensor vibrates in a particular direction according to Coriolis forces, and any deviations from the particular direction can be detected to measure the angle and/or angular turning rate. In another example, the angular sensor 118 includes an optical gyroscopic sensor, which senses the angle and/or angular turning rate of an object based on the interference of light which has passed through a very long coil of optical fiber, for example over 100 metres in length. Similarly, in additional embodiments, the angular sensor 118 may be a ring-laser gyroscope, or a differential accelerometer operable to measure the angle and/or angular turning rate.

The spin-control system 1OO is operable to apply differential torque between at least one wheel located on a right-side and at least one wheel located on a left-side of the electrical vehicle 102 when the electrical vehicle 102 executes turning maneuvers in operation. Throughout the present disclosure, the term 'differential torque' as used herein relates to providing different amount of toque to the different wheels of the electrical vehicle. Optionally, the power control arrangement 116 is configured to control the differential torque applied between at least one wheel located on a right-side and at least one wheel located on a leftside of the electrical vehicle 102 when the electrical vehicle 102 executes turning maneuvers. Optionally, in an event wherein the electrical vehicle 102 is manoeuvred in a left direction the power control arrangement 116 is configured to control the electrical power provided to the left-side front wheel 106 and the right-side front wheel 108. In such instance, the power control arrangement 116 is configured to provide more electrical power to the right-side front wheel 108 in order to generate more torque therein, as compared to the left-side front wheel 106. Optionally, in an event wherein the electrical vehicle 102 is manoeuvred in a right direction the power control arrangement 116 is configured to control the electrical power provided to the left-side front wheel 106 and the rightside front wheel 108. In such instance, the power control arrangement 116 is configured to provide more electrical power to the left-side front wheel 106 in order to generate more torque therein, as compared to the right-side front wheel 108.

Furthermore, spin-control system 100 is operable to apply differential torque when the angle and/or angular turning rate signal of the angular sensor 118 exceeds a threshold value. Throughout the present disclosure, the term 'differential torque' relates to a calculated value and/or pre-determined value of the magnitude of an angle and/or angular turning rate, exceeding which, the electrical vehicle 102 would be approaching a state of excessive spin. Optionally, the threshold value of the angle and/or angular turning rate is varied depending upon a velocity of travel of the electrical vehicle 102. For example, while making a turn, the electrical vehicle 102 may have an optimal angular turning rate in order to change the angular orientation of the electrical vehicle 102 in accordance to a radius of the turn. Furthermore, the angular turning rate may be greater when the vehicle 102 is moving at a higher velocity, and lesser when the vehicle 102 is moving at a lower velocity. In such instance, a threshold value of the angle and/or angular turning rate may be calculated based on the optimal turning rate at a particular velocity of movement. Furthermore, a calculation of threshold value of the angle and/or angular turning rate may also consider the intended steering angle of the vehicle 102.

Optionally, the spin-control system 100 may further comprise an indicator for providing indication of the angle and/or angular turning rate exceeding the threshold value. In an embodiment, an indicator may be installed at a vehicle console of the electrical vehicle 102, to be easily visible to the driver. Furthermore, the aforementioned indicator may comprise an indicating light, and a sound alert audible to the driver. Additionally, the indicator may be configured to indicate whenever the angle and/or angular turning rate exceed the threshold value. Such an indication is necessary as a safety-critical feature to alert the driver of the spin situation. Optionally, the indication is provided to the driver as an audio warning signal, so as not to distract the driver visually when making a complex manoeuver.

Optionally, the spin-control system 100 comprises additional sensing equipment to aid the angular sensor 118 to determine the state of spin of the electrical vehicle 102. Optionally, the system 100 may further comprise at least one torque sensor operatively coupled to at least one the rear wheels 110 and 112 for determining torque associated therewith for detecting loss of traction thereof. Typically, the rear wheels 110 and 112 are associated with a pre-determined value of torque, exceeding which may cause loss of traction for the rear wheels 110 and 112. Furthermore, the torque sensors are communicably linked with the power control arrangement 116. The torque sensors determine the torque transmitted to the rear wheels 110 and 112 as well as their individual rotational speeds. Using the data provided by the torque sensors, the spin-control system 100 may detect spinning of the vehicle 102 due to loss of traction at the rear wheels 110 and 112 more efficiently. Therefore, the action of the spin-control system 100 to apply a retarding force/and or reverse rotation to one or more rear wheels 110 and 112 may be correlated with the detection of a loss of traction.

Optionally, the spin-control system 100 also includes a data processor (not shown). The data processor receives the angle and/or angular turning rate of the vehicle 102 from the angular sensor 118. Additionally, the data processor compares the received angle and/or angular turning rate of the vehicle 102 to a calculated threshold value. Furthermore, the data processor is communicably linked to the power control arrangement 116. In such an embodiment, the data processor is operable to communicate the angle and/or angular turning rate signal to the power control arrangement 116 to apply a retarding force and/or reverse rotation to the rear wheels 110 and 112. Moreover, the data processor is operable to receive data provided by the torque sensors to enable the spin-control system 100 to detect loss of traction at the rear wheels 110 and 112.

According to an embodiment, in use, the spin-control system 100 measures an angular orientation of the vehicle 102 in terms of an angle and/or angular turning rate. Furthermore, the spin-control system 100 compares the measured angular orientation of the vehicle 102 with a threshold value of angle and/or angular turning rate. The threshold value may be dependent upon the speed of the vehicle 102. In an event wherein, the aforementioned threshold value is exceeded, the spincontrol system 100 communicates an angle and/or angular turning rate signal to the power control arrangement 116 indicating that the vehicle 102 is approaching a condition of excessive spin. In order to counter-act and prevent the aforesaid spin condition, the power control arrangement 116 operates to provide a retarding force and/or reverse rotation to the rear wheels 110 and 112 of the electrical vehicle 102. Optionally, the aforesaid retarding force and/or reverse rotation of the rear wheels 110 and 112 may be applied in an iterative manner depending upon the measured change in angle and/or angular turning rate of the vehicle 102 during the preceding iterations.

Furthermore, the spin-control system 100 in conjunction with the power control arrangement 116 and the electrical motor arrangement 120 continues to operate until the spin of the vehicle 102 is controlled and/or recovered. For example, the spin-control system 100 may continue to operate until the angle and/or angular turning rate signal from the angular sensor 118 falls below the threshold value.

The spin-control system 100 is further operable to apply a forwardlydirected traction force to the at least one electrical motor associated with the at least one front wheel, such as the electrical motors 120A and 120B, of the electrical vehicle 102 and a backwardly-directed retarding traction force to the at least one electrical motors associated with the rear wheel, such as the electrical motors 120C and 120D, of the electrical vehicle 102 to straighten-up a forward trajectory of the electrical vehicle 102 when the angle and/or angular turning rate signal of the angular sensor 118 exceeds a threshold value. Optionally, the spin-control system 100, based upon the drivers actuation of an accelerator pedal, a brake pedal and (optionally) a gear lever, and steering angle of the steering wheel of the electrical vehicle 102 selectively delivers electrical power to the electrical motors 120A and 120B to generate forwardly-directed traction force in the front wheel 106 and 108. Furthermore, the spin-control system 100, based upon the drivers actuation of an accelerator pedal, a brake pedal and (optionally) a gear lever, and steering angle of the steering wheel of the electrical vehicle 102 selectively delivers electrical power to the electrical motors 120C and 120D to generate backwardly-directed retarding traction force in the rear wheels 110 and 112. For example, in an event wherein the electrical vehicle 102 is operating in a wet, snowy or icy conditions, the spin-control system 100 is operable to provide a high electrical power to the electrical motors 120A and 120B associated with the front wheels 106 and 108 to generate a forwardly-directed traction force in order to straighten the direction in which the electrical vehicle 102 is travelling.

Furthermore, the high electrical power may be provided to the electrical motors 120A and 120B as the front wheels 106 and 108 control steering of the electrical vehicle 102. In such example, spin-control system 100, is operable to generate a backwardly-directed retarding traction force (such as drag) in the rear wheels 110 and 112 by providing a retarding force and/or reverse using the electrical motors 120C and 120D. Optionally, the spin-control system 100 is operable to selectively apply the forwardly-directed traction force and the backwardly-directed retarding traction force selectively to de-spin the electrical vehicle 102 while operating on a certain road surfaces, such as wet or slippery road surfaces. Furthermore, the backwardly-directed retarding traction force can be differentially applied to the pair of rear wheels 110 and 112 via the respective electrical motors 120C to 120D to assist to de-spin the electrical vehicle 102.

Optionally, the spin-control system 102 is operable to apply iteratively the forwardly-directed traction force and the backwardly-directed retarding traction force when the angle and/or angular turning rate signal exceeds the threshold value, as a function of a change in turning rate associated with each iteration. Optionally, the application of a momentary forwardly-directed traction force to one or more front wheels 106 and 108, and the backwardly-directed traction force to one or more rear wheels 110 and 112 by the electrical motor arrangement 120 has the effect of counter-acting the spin of the electrical vehicle 102. In a scenario where the electrical vehicle 102 is in a state of spin, the spincontrol system 100 operates to apply a forwardly-directed traction force to one or more front wheels 106 and 108, and a retarding force and/or reverse rotation to one or more rear wheels 110 and 112. Furthermore, if the angular sensor 118 detects a reduction in the angle and/or angular turning rate of the electrical vehicle 102, the spin-control system 100 continues to operate iteratively in a temporal manner of providing forwardly-directed traction force to the front wheels 106 and 108 and retarding force and/or reverse rotation of the rear wheels 110 and 112. The temporal manner of forwardly-directed traction force and retarding force and/or reverse rotation by the spin-control system 100 is dependent upon the change in the angle and/or angular turning rate associated with each preceding iteration. Therefore, the spin-control system 100 continues to operate until the spin of the vehicle 102 is controlled and/or recovered from. For example, the spin-control system 100 may continue to operate until the angle and/or angular turning rate signal from the angular sensor 118 falls below the threshold value. Optionally, the threshold value is varied dynamically as the vehicle recovers from a given spin.

The spin-control system and the method of performing spin-control for electrical vehicles as described in the present disclosure is a safety-critical feature aimed at improving road safety on wet and/or slippery road conditions and enhancing steering performance. Beneficially, the system disclosed efficiently prevents loss of traction on slick surfaces, such as wet or muddy roads, black ice or loose gravel. Furthermore, the system and method disclosed are relatively simple to implement and do not depend on driver intervention to control and recover from a spin. Therefore, the disclosed spin-control system has several advantages and enhances the traction control of electrical vehicles in inclement weather conditions, unfavorable surface conditions and high speeds.

Modifications to embodiments of the invention described in the foregoing are possible without departing from the scope of the invention as defined by the accompanying claims. Expressions such as including, comprising, incorporating, consisting of, have, is used to describe and claim the present invention are intended to be construed in a non-exclusive manner, namely allowing for items, components or elements not explicitly described also to be present. Reference to the singular is also to be construed to relate to the plural. Numerals included within parentheses in the accompanying claims are intended to assist understanding of the claims and should not be construed in any way to limit subject matter claimed by these claims.

Claims

1. A spin-control system for an electrical vehicle, wherein the electrical vehicle comprises a vehicle frame arrangement, a battery arrangement for storing energy, a power control arrangement for controlling an electrical power flow between the battery arrangement and an electrical motor arrangement, wherein the electrical motor arrangement is operable to drive a pair of front wheels and a pair of rear wheels of the electrical vehicle; characterized in that:

(i) the electrical motor arrangement includes four electrical motors for applying in operation torque to the pair of front wheels and rear wheels; wherein the electrical motors are mutually independently controllable by the power control arrangement of the electric vehicle; wherein motors associated with the pair of front wheels are implemented as in-hub electrical motors; and wherein motors associated with the pair of rear wheels are implemented as sprung elements of the vehicle frame arrangement and are coupled via a coupling arrangement to their corresponding wheels;

(ii) the spin-control system comprises an angular sensor for sensing an angular orientation of the electrical vehicle to provide an angle and/or angular turning rate signal for the spin-control system; and (iii) the spin-control system is operable to apply a differential torque between at least one wheel located on a right-side and at least one wheel located on a left-side of the electrical vehicle when the electrical vehicle executes turning maneuvers in operation and when the angle and/or angular turning rate signal of the angular sensor exceeds a threshold value.

2. A spin-control system of claim 1, characterized in that the spincontrol system is further operable to apply a forwardly-directed traction force to the at least one electrical motor associated with the at least one front wheel of the electrical vehicle and a backwardly-directed retarding traction force to the at least one electrical motors associated with the rear wheel of the electrical vehicle to straighten-up a forward trajectory of the electrical vehicle when the angle and/or angular turning rate signal of the angular sensor exceeds a threshold value.

3. A spin-control system of claim 1, characterized in that each of the motors associated with the pair of front wheels and the pair of rear wheels includes

- a casing;

- a stator mounted on the casing, the stator including one or more planar stator elements extending from the casing, wherein each of the one or more planar stator elements includes a central hole; and

- a rotor including

- a rotor shaft that is disposed within the central hole of each of the one or more planar stator elements of the stator; and

- one or more planar rotor elements attached to the shaft; wherein principal planes of the one or more planar stator and rotor elements are arranged mutually to abut with a magnetic separation gap therebetween, and the one or more planar stator elements and the one or more planar rotor elements are arranged to have electrical winding coil arrangements disposed thereon; and

- magnetic bearings coupled to ends of the rotor shaft.

4. A method of using an electrical vehicle spin-control system, wherein the electrical vehicle comprises a vehicle frame arrangement, a battery arrangement for storing energy, a power control arrangement for controlling an electrical power flow between the battery arrangement and 5 an electrical motor arrangement, wherein the electrical motor arrangement is operable to drive a pair of front wheels and a pair of rear wheels of the electrical vehicle; wherein the method includes:

(i) arranging for the electrical motor arrangement to include four electrical motors for applying in operation torque to the pair of front

10 wheels and rear wheels; wherein the electrical motors are mutually independently controllable by the power control arrangement of the electrical vehicle; wherein motors associated with the pair of front wheels are implemented as in-hub electrical motors; and wherein motors associated with the pair of rear wheels are implemented as sprung 15 elements of the vehicle frame arrangement and are coupled via a coupling arrangement to their corresponding wheels;

(ii) arranging for the electrical vehicle spin-control system to comprise an angular sensor for sensing an angular orientation of the electrical vehicle and measuring to provide an angular turning rate signal for the

20 electrical vehicle spin-control system; and (iii) operating the electrical vehicle_spin-control system to apply a differential torque between at least one wheel located on a right-side and at least one wheel located on a left-side of the electrical vehicle when the electrical vehicle executes turning maneuvers in operation and when the

25 angular turning rate signal of the angular sensor exceeds a threshold value;

characterized in that;

the electrical vehicle spin-control system:

i) measures an angular orientation of the electrical vehicle in 30 terms of an angular turning rate,

01 05 18 ii) compares the measured angular orientation of the vehicle with a threshold value of angular turning rate, wherein the threshold value is dependent on the speed of the vehicle, iii) whenever the aforementioned threshold value is exceeded,

5 communicates an angular turning rate signal to the power control arrangement indicating that the vehicle is approaching a condition of excessive spin, such that the power control arrangement operates the electrical motor arrangement to apply, by iteration, a retarding force or 10 reverse rotation to the rear wheels of the electrical vehicle and a forwardly-directed traction force to the front wheels of the electrical vehicle, the application of retarding force or reverse rotation and traction force being dependent on the measured change in angular turning rate of the electrical 15 vehicle during preceding iterations, in order to counter-act and prevent the condition of excessive spin until the spin of the vehicle is controlled, as determined by the electrical vehicle spin control system.

4. A spin-control system of any one of the preceding claims, characterized in that the rotor is operable to rotate at a maximum rotation rate in a range of 30000 rotations per minute (r.p.m.) to 100000 rotations per minute (r.p.m.).

5. A spin-control system of any one of the preceding claims, characterized in that the threshold value of the angle and/or angular turning rate is adaptively varied depending upon a velocity of travel of the electrical vehicle.

6. A spin-control system of any one of the preceding claims, characterized in that the angular sensor is implemented using at least one of: a resonating Coriolis sensor, an optical gyroscopic sensor, a ringlaser gyro, a differential accelerometer arrangement.

7. A spin-control system of any one of the preceding claims, characterized in that the system further comprises an indicator for providing to a user an indication of the angle and/or angular turning rate exceeding the threshold value.

8. A spin-control system of any one of the preceding claims, characterized in that the system is operable to apply iteratively the forwardly-directed traction force and the backwardly-directed retarding traction force when the angle and/or angular turning rate signal exceeds the threshold value, as a function of a change in the angle and/or angular turning rate associated with each iteration.

9. A spin-control system of any one of the preceding claims, characterized in that the system further comprises at least one torque sensor operatively coupled to at least of one the rear wheels for determining torque associated with the at least one the rear wheels for detecting loss of traction thereof.

10. A spin-control system of any one of the preceding claims, characterized in that each of the motors of the electrical motor arrangement uses at least one of: magnetic bearings, mechanical bearings, a combination of magnetic and mechanical bearings.

11. A method of using a spin-control system for an electrical vehicle, wherein the electrical vehicle comprises a vehicle frame arrangement, a battery arrangement for storing energy, a power control arrangement for controlling an electrical power flow between the battery arrangement and an electrical motor arrangement, wherein the electrical motor arrangement is operable to drive a pair of front wheels and a pair of rear wheels of the electrical vehicle; characterized in that the method includes:

(i) arranging for the electrical motor arrangement to include four electrical motors for applying in operation torque to the pair of front wheels and rear wheels; wherein the electrical motors are mutually independently controllable by the power control arrangement of the electric vehicle; wherein motors associated with the pair of front wheels are implemented as in-hub electrical motors; and wherein motors associated with the pair of rear wheels are implemented as sprung elements of the vehicle frame arrangement and are coupled via a coupling arrangement to their corresponding wheels;

(ii) arranging for the spin-control system to comprise an angular sensor for sensing an angular orientation of the electrical vehicle to provide an angle and/or angular turning rate signal for the spin-control system; and (iii) operating the spin-control system to apply a differential torque between at least one wheel located on a right-side and at least one wheel located on a left-side of the electrical vehicle when the electrical vehicle executes turning maneuvers in operation and when the angle and/or angular turning rate signal of the angular sensor exceeds a threshold value.

01 05 18

Amendments to the claims have been filed as follows

1. An electrical vehicle spin-control system, wherein the electrical vehicle comprises a vehicle frame arrangement, a battery arrangement for storing energy, a power control arrangement for controlling an

5 electrical power flow between the battery arrangement and an electrical motor arrangement, wherein the electrical motor arrangement is operable to drive a pair of front wheels and a pair of rear wheels of the electrical vehicle, wherein:

(i) the electrical motor arrangement includes four electrical

10 motors for applying in operation torque to the pair of front wheels and rear wheels; wherein the electrical motors are mutually independently controllable by the power control arrangement of the electrical vehicle; wherein motors associated with the pair of front wheels are implemented as in-hub electrical motors; and wherein motors associated with the pair

15 of rear wheels are implemented as sprung elements of the vehicle frame arrangement and are coupled via a coupling arrangement to their corresponding wheels;

(ii) the electrical vehicle spin-control system comprises an angular sensor for sensing an angular orientation of the electrical vehicle

20 and measuring an angular turning rate signal to communicate angular turning rate signal to the power control arrangement; and (Hi) the electrical vehicle spin-control system is operable to apply a differential torque between at least one wheel located on a right-side and at least one wheel located on a left-side of the electrical vehicle when 25 the electrical vehicle executes turning maneuvers in operation and when the angular turning rate signal of the angular sensor exceeds a threshold value, and wherein the electrical vehicle spin control system:

i) measures an angular orientation of the electrical vehicle in terms of an angular turning rate,

20 2. An electrical vehicle spin-control system of claim 1, configured and arranged to selectively deliver electrical power to the electrical motor arrangement to provide a backwardly-directed retarding force in the rear wheels and a forwardly-directed traction force to the front wheels of the electrical vehicle, based upon the driver's actuation of an accelerator 25 pedal, a brake pedal, and steering angle of the steering wheel of the electrical vehicle.

3. An electrical vehicle spin-control system of claim 1 or claim 2, wherein the retarding force can be differentially applied to the pair of rear wheels via the respective electrical motors to assist to de-spin the 30 electrical vehicle.

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