WO2019053270A2

WO2019053270A2 - Electrical vehicle and method of providing motive torque in electric vehicle using at least two electrical motors

Info

Publication number: WO2019053270A2
Application number: PCT/EP2018/075100
Authority: WO
Inventors: Albert Lam
Original assignee: Detroit Electric Ev Technologies (Zhejiang) Limited
Priority date: 2017-09-15
Filing date: 2018-09-17
Publication date: 2019-03-21
Also published as: WO2019053270A3

Abstract

Disclosed is an electrical vehicle and a method of providing motive torque in an electrical vehicle. The electrical vehicle includes a vehicle frame arrangement, at least one front wheel and a pair of rear wheels rotatably coupled onto the vehicle frame arrangement, and an electrical motor arrangement for applying in operation torque to at least the pair of rear wheels to propel the electrical vehicle in a forward or a reverse direction, characterized in that (i) the electrical motor arrangement includes at least two electrical motors for applying in operation torque to the at least the pair of rear wheels; (ii) the at least two electrical motors are mutually independently controllable from a motor control arrangement of the electrical vehicle; and (iii) the at least two electrical motors are implemented as a sprung element of the vehicle frame arrangement and are coupled via a coupling arrangement to their corresponding wheels, or an electrical vehicle and a method of providing motive torque in an electrical vehicle. The electric vehicle including a vehicle frame arrangement, at least three wheels coupled onto the vehicle frame arrangement, and an electrical motor arrangement for applying torque to the at least three wheels to propel the electric vehicle in a forward or a reverse direction, characterized in that: the electrical motor arrangement includes at least three electrical motors for applying torque to the at least three wheels; the at least three electrical motors are mutually independently controllable from a motor control arrangement of the electric vehicle; at least one of the at least three electrical motors is implemented as an in-hub electrical motor; and at least one of the at least three electrical motors is implemented as a sprung element of the vehicle frame arrangement and is coupled via a coupling arrangement to corresponding wheel.

Description

ELECTRICAL VEHICLE AND METHOD OF PROVIDING MOTIVE TORQUE IN ELECTRIC VEHICLE USING AT LEAST TWO

ELECTRICAL MOTORS

TECHNICAL FIELD

The present disclosure relates generally to vehicles; more specifically, the present relates to electrical vehicles including vehicle frame arrangements, at least one front wheel and a pair of rear wheels rotatably coupled onto such vehicle frame arrangements, and an electrical motor arrangement for providing motive power to the electric vehicles. Furthermore, the present disclosure also relates to methods of providing motive torque in the aforementioned electrical vehicles.

BACKGROUND

Recently, in human history, vehicles have become an integral part of daily life. Such vehicles, and specifically automobiles, have introduced convenience and comfort to address human transportation needs. Contemporarily, automobiles are capable of traversing distances of several hundred miles or kilometres in relatively short periods of time, for example within a few hours. With advancements in the automobile technology, manufacture of electrical vehicles is now being manufactured in increasing numbers.

Electrical vehicles are potentially capable of playing a significant role in reducing environmental pollution and encouraging sustainable technologies. Typically, the electrical vehicles produce fewer by-products that cause anthropogenic climate change in comparison to conventional vehicles powered by fossil fuels, especially when the electrical vehicles are powered from renewable energy sources such as wind turbines, hydroelectric generators, tidal power generators, geothermal power generator, solar power generators and such like. However, it has been appreciated that electrical vehicles of superlative performance have to be manufactured to encourage the use of electrical vehicles in place of corresponding-performance internal combustion engine vehicles. Generally, contemporary electrical vehicles include high performance vehicles which utilize powerful motor arrangements and provide brisk accelerations when in operation. Usually, such motor arrangements are prone to overheating issues while providing high operational torque to the electrical vehicle. Such overheating issues may severely affect performance and efficiency of the electrical vehicle. Furthermore, conventional motor arrangements used in electrical vehicles are known to include a stator that employs permanent magnets. However, use of such permanent magnets leads to a large and heavy design of the motor arrangements that may adversely affect weight and stability of the electrical vehicle. Furthermore, to provide high performance, such stators may include rare-earth magnets that leads to high manufacturing costs associated with the motor arrangements and consequently, high manufacturing costs associated with the electrical vehicle. Often, the motor arrangements employ a single electrical motor and a differential element to provide torque to wheels of the electrical vehicle. However, use of the single electrical motor and the separate differential element increases weight of the electrical vehicle.

Contemporarily, vehicles have become an integral part of everyday life. Such vehicles, and specifically automobiles, have introduced convenience and comfort to address daily transportation needs. Nowadays, automobiles are capable of traversing distances of several hundred miles or kilometres in a relatively short period of time, for example within a period of hours. With recent advancements in automobile technology, there has been an unprecedented increase in manufacture of electrical vehicles. Electrical vehicles are potentially capable of playing a significant role in reducing environmental pollution and encouraging sustainable technologies. Typically, the electrical vehicles produce fewer by-products that cause anthropogenic climate change in comparison to conventional vehicles powered by fossil fuels. However, it has been appreciated that electrical vehicles of superlative performance have to be manufactured to encourage the use of electrical vehicles in place of corresponding- performance internal combustion engine vehicles.

Generally, contemporary electrical vehicles include high performance vehicles which support powerful motor arrangements and provide brisk accelerations when in operation. Usually, such motor arrangements are prone to overheating issues while providing high operational torque to the electrical vehicle. Such overheating issues may severely affect performance and efficiency of the electrical vehicle. Furthermore, conventional motor arrangements used in electrical vehicles are known to include a stator that employs permanent magnets. However, use of such permanent magnets leads to a large and heavy design of the motor arrangements that may adversely affect weight and stability of the electrical vehicle. Furthermore, to provide high performance, such stators may include rare-earth magnets that leads to high manufacturing costs associated with the motor arrangements and consequently, high manufacturing costs associated with the electrical vehicle. Often, the motor arrangements employ a single electrical motor and a differential element to provide torque to wheels of the electrical vehicle. However, use of the single electrical motor and the separate differential element increases weight of the electrical vehicle. Furthermore, the conventional motor arrangements comprises of electric motors configured to provide rotational torque to rear wheels. However, in such cases, driving the electrical vehicle may lead to slipping of wheels and consequently result in accidents. Therefore, in light of the foregoing discussion, there is a need to overcome the aforementioned drawbacks associated with conventional electrical vehicles.

SUMMARY

The present disclosure seeks to provide an improved electrical vehicle.

The present disclosure also seeks to provide an improved method of providing motive torque in an electrical vehicle.

According to a first aspect, an embodiment of the present disclosure provides an electrical vehicle including a vehicle frame arrangement, at least one front wheel and a pair of rear wheels rotatably coupled onto the vehicle frame arrangement, and an electrical motor arrangement for applying in operation torque to at least the pair of rear wheels to propel the electrical vehicle in a forward or a reverse direction, characterized in that:

(i) the electrical motor arrangement includes at least two electrical motors for applying in operation torque to the at least the pair of rear wheels;

(ii) the at least two electrical motors are mutually independently controllable from a motor control arrangement of the electrical vehicle; and

(iii) the at least two electrical motors are implemented as a sprung element of the vehicle frame arrangement and are coupled via a coupling arrangement to their corresponding wheels. The electrical vehicle of the present disclosure includes a substantially lighter electrical motor arrangement as compared to motor arrangements of conventional electrical vehicles. Furthermore, owing to arrangement and operation of components within the electrical vehicle described herein, such an electrical vehicle is substantially lighter in weight, less prone to overheating issues, and has good balance whilst being driven.

According to a second aspect, an embodiment of the present disclosure provides a method of providing motive torque in an electrical vehicle including a vehicle frame arrangement, at least one front wheel and a pair of rear wheels rotatably coupled onto the vehicle frame arrangement, and an electrical motor arrangement for applying in operation torque to at least the pair of rear wheels to propel the electrical vehicle in a forward or a reverse direction, characterized in that the method includes:

(i) arranging for the electrical motor arrangement to include at least two electrical motors for applying in operation torque to the at least the pair of rear wheels;

(ii) arranging for the at least two electrical motors to be mutually independently controllable from a motor control arrangement of the electrical vehicle; and

(iii) arranging for the at least two electrical motors to be implemented as a sprung element of the vehicle frame arrangement and to be coupled via a coupling arrangement to their corresponding wheels.

According to a third aspect, an embodiment of the present disclosure provides an electric vehicle including a vehicle frame arrangement, at least three wheels rotatably coupled onto the vehicle frame arrangement, and an electrical motor arrangement for applying in operation torque to the at least three wheels to propel the electric vehicle in a forward or a reverse direction, characterized in that: (i) the electrical motor arrangement includes at least three electrical motors for applying in operation torque to the at least three wheels;

(ii) the at least three electrical motors are mutually independently controllable from a motor control arrangement of the electric vehicle; (iii) at least one of the at least three electrical motors is implemented as an in-hub electrical motor; and

(iv) at least one of the at least three electrical motors is implemented as a sprung element of the vehicle frame arrangement and is coupled via a coupling arrangement to its corresponding wheel.

The electrical vehicle of the present disclosure includes a substantially lighter electrical motor arrangement as compared to motor arrangements of conventional electrical vehicles. Furthermore, owing to arrangement and operation of components within the electrical vehicle described herein, such an electrical vehicle is substantially lighter in weight, less prone to overheating issues, and has good balance whilst being driven.

According to a fourth aspect, an embodiment of the present disclosure provides a method of providing motive torque in an electric vehicle including a vehicle frame arrangement, at least three wheels rotatably coupled onto the vehicle frame arrangement, and an electrical motor arrangement for applying in operation torque to the at least three wheels to propel the electric vehicle in a forward or a reverse direction, characterized in that the method includes:

(i) arranging for the electrical motor arrangement to include at least three electrical motors for applying in operation torque to the at least three wheels;

(ii) arranging for the at least three electrical motors to be mutually independently controllable from a motor control arrangement of the electric vehicle; (iii) arranging for at least one of the at least three electrical motors to be implemented as an in-hub electrical motor; and (iv) arranging for at least one of the at least three electrical motors to be implemented as a sprung element of the vehicle frame arrangement and to be coupled via a coupling arrangement to its corresponding wheel.

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 plan view illustration of an electrical vehicle, in accordance with an embodiment of the present disclosure;

FIG. 2 is a schematic illustration of a block diagram depicting components of the electrical vehicle, in accordance with an embodiment of the present disclosure; and

FIG. 3 is an illustration of steps of a method of providing motive torque in an electric vehicle, in accordance with an embodiment of the present disclosure. FIG. 4 is a schematic illustration of a plan view illustration of an electrical vehicle, in accordance with another embodiment of the present disclosure;

FIG. 5 is a block diagram of the battery arrangement of an electrical vehicle, in accordance with an embodiment of the present disclosure; FIG. 6 is a schematic illustration of a block diagram depicting components of the electrical vehicle, in accordance with an embodiment of the present disclosure; and

FIG. 7 is an illustration of steps of a method of providing motive torque in an electric 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 an electrical vehicle. Furthermore, embodiments of the present disclosure are concerned with a method of providing motive torque in the electrical vehicle.

Referring to FIG. 1, there is shown a plan view illustration of an electrical vehicle 100, in accordance with an embodiment of the present disclosure. The electrical vehicle 100 includes a vehicle frame arrangement 102, at least one front wheel (depicted as a pair of steerable front wheels 104 and 106) and a pair of rear wheels (depicted as rear wheels 108 and 110), rotatably coupled onto the vehicle frame arrangement 102, and an electrical motor arrangement 112 for applying in operation torque to at least the pair of rear wheels 108 and 110 to propel the electrical vehicle 100 in a forward or a reverse direction. Additionally, or alternatively, optionally, the electrical motor arrangement 112 applies in operation torque to the at least one front wheel 104 and 106. Optionally, the at least front wheel 104 and 106 are provided with in-hub electrical motors for providing propulsion to the electrical vehicle 100; optionally, the in-hub electrical motors are mutually independently controllable. As shown, the front wheel 104 is a left front wheel, whereas the front wheel 106 is a right front wheel. Furthermore, as shown, the rear wheel 108 is a left rear wheel, whereas the rear wheel 110 is a right rear wheel.

Throughout the present disclosure, the term "vehicle frame arrangement" relates to a physical frame or structure to which various components (for example, such as engine, transmission, drive shaft, suspension and the like) of the electrical vehicle 100 are attached. Optionally, the vehicle frame arrangement 102 includes a platform to which a suspension system (now shown) of the electrical vehicle 100 is coupled, and a transverse beam member disposed transversely (namely, orthogonally relative to an elongate axis of the vehicle frame arrangement 102) at a location approximately mid-way along the vehicle frame arrangement 102. More optionally, the vehicle frame arrangement 102 includes an anti-roll bar (not shown) . In such an instance, the anti-roll bar is configured to prevent rolling of the electrical vehicle 100 whilst the electrical vehicle 100 maneuvers sharp turns at a high speed.

Furthermore, as shown in FIG. 1, the at least one front wheel 104 and 106 is rotatably coupled onto the vehicle frame arrangement 102. Similarly, the pair of rear wheels 108 and 110 are rotatably coupled onto the vehicle frame arrangement 102. It will be appreciated that throughout the present disclosure, the term "rotatably coupled" relates to a circular movement of a given wheel around an axis (namely, about an axis of an axle associated therewith) . Furthermore, optionally, the vehicle frame arrangement 102 is coupled with the front and rear wheel axles via mechanical bearings (not shown) . In an embodiment, the electrical vehicle 100 includes four wheels, namely a pair of front wheels 104 and 106 and the pair of rear wheels 108 and 110. In such an embodiment, the wheels 104-110 of the electrical vehicle 100 may be steered by employing a steering wheel 114 of the electrical vehicle 100. The steering wheel 114 is optionally coupled via a power-assisted steering arrangement (not shown) to the pair of front wheels 104 and 106. Optionally, such a power-assisted steering arrangement is controllable in accordance with preferences of a user of the electrical vehicle 100 and/or to driving conditions during use of the electrical vehicle 100 (for example, adaptively as a function of a speed of travel of the electrical vehicle 100, as a function of weather conditions to which the electrical vehicle 100 is confronted, road surface conditions and so forth) .

Optionally, the at least one front wheel 104 and 106 is associated with a front suspension arrangement (not shown) and the pair of rear wheels 108 and 110 are associated with a rear suspension arrangement (not shown). Optionally, in this regard, the vehicle frame arrangement 102 of the electrical vehicle 100 includes coil springs having a predetermined stiffness corresponding to the front and rear suspension arrangements. In such an instance, the stiffness of the coil springs of the front and rear suspension arrangements allows for substantial compensation of vertical movement (or "bounce") of the electrical vehicle 100 during operation thereof, and therefore, provides a more comfortable driving experience for the user of the electrical vehicle 100. Furthermore, optionally, at least one front wheel 104 and 106 and the pair of rear wheels 108 and 110 are mounted on parallel herring-bone suspension arrangements having corresponding spring and damper arrangements (not shown). Optionally, each of the spring and damper arrangements comprises a damper housed concentrically within a spring. In an example, the damper may be implemented as an oil damper, a piezo-electric stack active damper, a magnetic rheological damper, or any combination of these.

It will be appreciated that such spring and damper arrangements may be effective at mutually different frequency spectrum ranges, such that use of a combination of such spring and damper arrangements is capable of providing damping effectively over a greater frequency range, resulting in a more comfortable driving experience for the user of the electrical vehicle 100. In an example, the magnetic rheological damper employs magnetic-particles and oil mixture having at least an anti-coagulant, wherein damping characteristics of the magnetic rheological damper are optionally actively varied, namely adaptively varied, when driving to cope with different road surfaces and/or user preferences.

Optionally, the spring and damper arrangements corresponding to the front and rear suspension arrangements are mutually similar. Alternatively, optionally, the front suspension arrangement is associated with a simple oil-damper, whereas the rear suspension arrangement is associated with the magnetic rheological damper, whose operating characteristics can be adaptively varied depending upon driving conditions, travelling speed of the electrical vehicle 100, and so forth.

Furthermore, the electrical motor arrangement 112 includes at least two electrical motors, depicted as electrical motors 116 and 118 for applying in operation torque to the at least the pair of rear wheels 108 and 110, respectively. It will be appreciated that such in operation torque applied to at least the pair of rear wheels 108 and 110 allows for propelling the electrical vehicle 100 in the aforesaid forward direction or in the aforesaid reverse direction. In such an instance, the at least two electrical motors 116 and 118 receive electrical power from a battery arrangement 122 of the electrical vehicle 100 to provide a rotational force to at least the pair of rear wheels 108 and 110 for producing a rotational motion therein for propelling the electrical vehicle 100. Optionally, the at least two electrical motors 116 and 118 are operable to provide in operation torque to the at least one front wheel 104 and 106. Alternatively, optionally, the at least one front wheel 104 and 106 are provided with in-hub electrical motors for providing motive power to propel the electrical vehicle 100.

Optionally, the battery arrangement 122 of the electrical vehicle 100 is implemented as a floor-mounted flat battery unit, or as an L-shaped battery unit mounted behind seats of the electrical vehicle 100. Furthermore, optionally, the battery arrangement 122 is supplemented with supercapacitors for providing for peaks in current demand, for example during rapid acceleration of the electrical vehicle 100 and/or during rapid regenerative braking of the electrical vehicle 100. Moreover, optionally, the battery arrangement 122 is mounted in proximity of the at least two electrical motors 116 and 118 of the electrical vehicle 100.

Furthermore, the at least two electrical motors 116 and 118 are mutually independently controllable from a motor control arrangement 120 of the electrical vehicle 100. It will be appreciated that the term "motor control arrangement" used herein relates to hardware, software, firmware, or a combination of these, operable to control operation of the at least two electrical motors 116 and 118 of the electrical motor arrangement 112. Furthermore, the motor control arrangement 120 allows for the at least two electrical motors 116 and 118 to be mutually independently controlled, and also allows for their manner of control to be mutually independently defined. As an example, the motor control arrangement 120 may control the at least two electrical motors 116 and 118 to provide a mutually different amount of electrical power thereto, resulting in a mutually different amounts of torque to be delivered to the pair of rear wheels 108 and 110 based upon a driving condition during use of the electrical vehicle 100;, for example, mutually different amounts of torque are useful utilized when grip of tires (tyres) of the pair of wheels 108 and 110 onto a road surface is compromised by snow, ice, mud or loose gravel (for example, to assist to recover from an unintended lateral sliding or spinning motion of the electrical vehicle 100).

Moreover, in the electrical vehicle 100, the at least two electrical motors 116 and 118 are implemented as sprung elements of the vehicle frame arrangement 102 and are coupled via their respective flexible torque coupling arrangements 124 and 125 to their corresponding rear wheels 108 and 110, respectively. As shown, the at least two electrical motors 116 and 118 are coupled via their respective torque coupling arrangements 124 and 125 to the pair of wheels' rear wheels 108 and 110, respectively. Throughout the present disclosure, the term "sprung element of the vehicle frame arrangement" relates to an element, whose mass is supported by the suspension system (namely, the front and rear suspension arrangements) of the electrical vehicle 100. Furthermore, as the at least two electrical motors 116 and 118 are mounted on the vehicle frame arrangement 102, and mass of the vehicle frame arrangement 102 is supported by the suspension system of the electrical vehicle 100, mass of the at least two electrical motors 116 and 118 is also supported by the suspension system of the electrical vehicle 100.

Furthermore, throughout the present disclosure the term "flexible torque coupling arrangement", used herein, relates to at least one mechanical element that is operable, namely configured, to transmit in operation the torque generated by the at least two electrical motors 116 and 118 to their corresponding wheels 108 and 110. Furthermore, optionally, the coupling arrangements 124 and 125 are also configured to transmit in operation the torque generated by the at least two electrical motors 116 and 118 to the at least one front wheel 104 and 106. As aforementioned, alternatively, the at least one front wheel 104 and 106 are provided with in-hub electrical motors for providing motive force to propel the electrical vehicle 100.

Optionally, the coupling arrangements 124 and 125 include at least one gear box arrangement depicted as gear boxes 126 and 128; optionally, the gear boxes 126 and 128 are implemented as planetary gear arrangements, variomatic gear arrangements providing a continuously variable gearing ratio or similar. Optionally, the coupling arrangements 124 and 125 include at least one clutch member (not shown) for selectively coupling or decoupling torque transmission therethrough. Shafts (not shown) of the at least two electrical motors 116 and 118 is coupled to their respective at least one clutch member. The clutch member is further coupled to the gear box arrangements 126 and 128, wherein the gear box arrangements 126 and 128 are configured for providing in operation torque (namely, a geared output torque) to the at least the pair of rear wheels 108 and 110. The gear box arrangements 126 and 128 include an output shaft associated therewith for driving their respective at least the pair of rear wheels 108 and 110, for example, by employing flexible knuckle joints, for propelling the electrical vehicle 100 when in operation. Optionally, when the gear box arrangements 126 and 128 are operated in an automatic transmission mode, namely as a continuously-variable torque converter, the clutch member is used less frequently, but is nevertheless coordinated with operation of the gear box arrangements 126 and 128 to avoid any slippage occurring within the clutch member. Alternatively, when the gear box arrangements 126 and 128 are operated in a manual transmission mode, the gear box arrangements 126 and 128 have discrete gear ratios.

Optionally, the at least two electrical motors 116 and 118 are implemented as in-hub electrical motors. In such an instance, for a given rear wheel (for example, such as the rear wheel 108), its corresponding electrical motor (for example, such as the electrical motor 118) and its corresponding gear box arrangement (for example, such as the gear box arrangement 126) are implemented as an in-hub arrangement. Optionally, the electrical vehicle 100 includes two front wheels 104 and 106 and two rear wheels 108 and 110, wherein the two rear wheels 108 and 110 are provided with corresponding two rear electrical motors 116 and 118 mounted onto the vehicle frame arrangement 102, such that the two rear electrical motors 116 and 118 are implemented as sprung mass of the electrical vehicle 100, and coupled to their respective wheels 108 and 110 via a flexible torque-coupling arrangement (for example, such as the coupling arrangements 124 and 125).

Optionally, the flexible torque-coupling arrangement includes two torque coupling members (not shown) associated with the pair of rear wheels 108 and 110. More optionally, the flexible torque-coupling arrangement may be provided by using at least one coupling member including, but not limited to, jaw-type coupling, Oldham Coupling and/or universal joints. Beneficially, the flexible torque-coupling arrangement accommodates misalignment between shafts of the at least two electrical motors 116 and 118 under different load conditions. Optionally, the motor control arrangement 120 is operable to apply differential torque between right-side wheels (for example, such as the right-side wheel 110) and left-side wheels for example, such as the leftside wheel 108) of the electrical vehicle 100 when the electrical vehicle 100 executes turning maneuvers when in operation. The electrical motor control arrangement 120 applies differential torque between the right- side rear wheel 110 and the left-side rear wheel 108 of the electrical vehicle 100 when the electrical vehicle 100 executes turning maneuvers when in operation. Throughout the present disclosure, the term ^{^}differential torque ' used herein relates to provision of different amounts of torque to different wheels of the electrical vehicle 100. As an example, in an event wherein the electrical vehicle 100 is maneuvered in a left direction, the motor control arrangement 120 is configured to control electrical power provided to the left-side rear wheel 108 and the right- side rear wheel 110 in a manner that the motor control arrangement 120 provide more electrical power to the right-side rear wheel 110 in order to generate more torque therein, as compared to the left-side rear wheel 108. This may be attributed to the fact that the right-side rear wheel 110 is required to traverse a larger distance as compared to the left-side rear wheel 108 while maneuvering in the left direction. Similarly, as another example, in an event wherein the electrical vehicle 100 is maneuvered in a right direction the motor control arrangement 120 is configured to control electrical power provided to the left-side rear wheel 108 and the right-side rear wheel 110 in a manner that the motor control arrangement 120 provides more electrical power to the left-side rear wheel 108 in order to generate more torque therein, as compared to the right-side rear wheel 110. This may be attributed to the fact that the leftside rear wheel 108 is required to traverse a larger distance as compared to the right-side rear wheel 110 while maneuvering in the right direction. Optionally, each of the at least two electrical motors 116 and 118 includes a casing (not shown). The casing is operable to accommodate components of the each of the at least two electrical motors 116 and 118, as described herein below. In one example, the casing is implemented as a hollow cylindrical structure that is operable to accommodate the components of the each of the at least two electrical motors 116 and 118. In another example, the casing is implemented as a hollow cylindrical structure including a plurality of cylindrical portions, for example two semi-cylindrical halves. In such an instance, the semi- cylindrical halves are operable to be arranged, namely mutually cooperate, along an abutting surface thereof, for example a planar surface thereof, to provide the casing. It will be appreciated that such an implementation of the casing including the semi-cylindrical halves enables convenient assembly (and/or disassembly) of the each of the at least two electrical motors 116 and 118 by enabling easy arrangement of the components of the each of the at least two electrical motors 116 and 118 therein. Furthermore, optionally, the each of the at least two electrical motors 116 and 118 includes a stator (not shown) mounted on the casing. The stator is a stationary component of the each of the at least two electrical motors 116 and 118. Furthermore, the stator is operable to provide a magnetic field to enable operation of one or more components of the each of the at least two electrical motors 116 and 118. Moreover, optionally, the stator includes one or more planar stator elements, for example implemented as one or more radial plate-like elements having a circular periphery, extending from the casing, wherein each of the one or more planar stator elements includes a central hole, for example a central circular hole. In an example, the one or more planar stator elements are attached to an inner surface of the casing. In one example, the one or more planar stator elements are implemented as semi-circular half plates that are operable to be arranged to form the one or more planar stator elements. Additionally, optionally, the one or more planar stator elements includes a central hole that enables one or more components (such as the shaft) of each of at least two electrical motors 116 and 118 to be accommodated therein.

Furthermore, optionally, each of the at least two electrical motors 116 and 118 includes a rotor (not shown) including (i) a shaft that is disposed within the central hole of each of the one or more planar stator elements of the stator, and (ii) one or more planar rotor elements, for example implemented as one or more radial plate-like elements, attached to the shaft. Specifically, the rotor is a rotatable component of the each of the at least two electrical motors 116 and 118 that enables generation of torque, for example, to rotate at least the pair of rear wheels 108 and 110 associated with the electrical vehicle 100. In an embodiment, the rotors of the at least two electrical motors 116 and 118 are operable to rotate at a maximum rotation rate in a range of 30000 rotations per minute to 100000 rotations per minute. It will be appreciated that such a high maximum rotation rate of the rotors enables a high speed operation of the each of the at least two electrical motors 116 and 118, as well as enabling the at least two electrical motors 116 and 118 to be constructed in a very compact format and yet able to generate mechanical output power of up to, for example, 150 kW each. By "very compact format" is meant, for example, a casing length in a range of 30 cm to 50 cm, and a casing outer diameter in a range of 25 cm to 40 cm, with an overall motor weight in a range of 4 kg to 15 kg. For example, such high rotation rate of the rotors enables high rate of change of flux associated with a magnetic field of the stators of the each of the at least two electrical motors 116 and 118. Additionally, optionally, the shaft of the rotor is implemented as a cylindrical structure that is operable to rotate around an axis (such as an axis passing through center of the cylindrical shaft) . Furthermore, the rotor includes one or more planar rotor elements attached to the shaft. Furthermore, the one or more radial plate-like rotor elements are attached to the shaft of the rotor along the axis thereof. In such a case, the one or more planar stator elements and the one or more planar rotor elements are associated with principal planes that are arranged mutually to abut with a magnetic separation gap therebetween so that the rotor is able to rotate relative to the stator. For example, the one or more planar rotor elements are attached to the 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 radial plate-like rotor elements of the rotor are disposed in a gap formed by two adjacent planar stator elements. It will be appreciated that 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 planes of the one or more planar stator elements and the one or more planar stator elements.

Moreover, optionally, the one or more planar, namely radial plate-like, stator and 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 a magnetic field that interacts with a magnetic field generated by corresponding one or more planar stator elements, to enable the rotation of the rotors of the each of the at least two electrical motors 116 and 118.

Furthermore, optionally, the each of the at least two electrical motors 116 and 118 includes magnetic bearings coupled to ends of the shaft of the rotor. For example, the rotor is operable to rotate at high maximum rotation rates, such as, in a range of 30000 rotations per minute (r.p.m.) to 100000 rotations per minute (r.p.m.). In such an instance, the magnetic bearings are operable to prevent physical contact between the shaft and one or more other components of the at least two electrical motors 116 and 118, such as, the one or more planar stator elements. By employing such magnetic bearings, it is feasible, potentially, to avoid any wear-and-tear occurring in the at least two electrical motors 116 and 118, thereby providing them with exceptionally long duration maintenance-free operation.

High-performance compact digital motors are known for use in portable electrical appliances, for example portable vacuum cleaners and hair driers. Such compact digital motors are described, for example, in a published patent document WO2010/112930 A2 ^High-speed electric system", applicant - Dyson Technology Ltd., UK) . These high- performance compact digital motors employ rare-earth permanent magnets. Principles of digital commutation of electrical motors as described in the published patent document WO2010/112930 A2 are hereby incorporated by reference to the document.

Furthermore, optionally, at least one, for example both, of the at least two electrical motors 116 and 118 is operable to function as a digitally- commutated electrical motor, wherein, during commutation, current pulses are applied to commutation windings (not shown) of the at least two electrical motors 116 and 118, and a free-wheeling period is implemented between the current pulses during which the commutation windings are non-energized. It will be appreciated that such digital commutation is provided to generate motion in the at least one of the at least two electrical motors 116 and 118. Furthermore, digital commutation may be implemented using the digitally controlled current pulses. Specifically, the commutation windings of the at least one electrical motor of the at least two electrical motors 116 and 118 may comprise electrical winding coil arrangement (not shown) disposed on the one or more planar stator elements of the stator of such at least one motor. In an exemplary implementation, current pulses may be provided to a phase coil PI of the commutation windings using a switching control unit, specifically, to a switching element SI for generating a motion in the rotor of such at least one electrical motor. Subsequently, the current pulses may be switched to a phase coil P2 of the commutation windings using a switching element S2 to sustain the generated motion. Furthermore, the current pulses may be switched continuously from phase coil PI to P2, P2 to P3 and subsequently, P3 to PI to maintain a rotational motion of the at least two electrical motors 116 and 118. Specifically, the phase coils PI, P2 and P3 are beneficially energized in sequence as the rotor rotates, and the coils PI, P2 and P3 are not energized simultaneously, namely only one commutated phase is energized at any given time. Therefore, a free-wheeling period may be implemented between the switching of current between the phase coils. Optionally, the at least two electrical motors 116 and 118 are coupled to a planetary gearbox arrangement, as aforementioned, for coupling a torque generated at the rotors to their corresponding wheels (namely, the wheel 108 corresponding to the electrical motor 116, and the wheel 110 corresponding to the electrical motor 118) of the electrical vehicle 100. As an example, the at least one gear box arrangement, depicted as gear boxes 126 and 128, may be the planetary gearbox arrangement. In an embodiment, the shafts of the at least two electrical motors 116 and 118 are directly coupled to the planetary gearbox arrangement, wherein the planetary gearbox arrangement is configured for providing a geared output torque. The planetary gearbox arrangement further includes output shafts thereof for driving at least the pair of rear wheels 108 and 110 for propelling the electrical vehicle 100 when in operation. Beneficially, the planetary gearbox arrangement provides multiple gear ratios from a compact size of gearbox casing. Furthermore, in such a example, use of the planetary gearbox arrangement allows for low transmission losses. In another embodiment, the shafts of the at least two electrical motors 116 and 118 are coupled to their aforementioned clutch members. The clutch members are further coupled to the planetary gearbox arrangement. Thereafter, the planetary gearbox arrangement transfers the geared output torque, via its output shaft, to at least the pair of rear wheels 108 and 110 for propelling the electrical vehicle 100 when in operation. Optionally, cog wheels of the planetary gear arrangement are manufactured using advanced 3D printing techniques for metal powder sintering of printed shapes, or using hydraulically- pressed sintered metal construction. More optionally, the planetary gearbox arrangement includes a cascaded configuration of a plurality of planetary gears. Throughout the present disclosure the term "cascaded configuration", used herein, relates to an arrangement of the plurality of planetary gears in a sequential, adjoining and compact manner. Beneficially, the cascaded configuration of a plurality of planetary gears allows for light weight and compact size of the coupling arrangement 112, while also providing for high gearing ratios to be achieved, for example in excess of 100 times rotation rate reduction.

Referring to FIG. 2, there is shown a block diagram depicting components of the electrical vehicle 100, in accordance with an embodiment of the present disclosure. As shown, the electrical vehicle 100 includes the battery arrangement 122, the motor control arrangement 120, and the electrical motor arrangement 112. As mentioned previously, the electrical motor arrangement 112 includes the at least two electrical motors 116 and 118 whose rotors are collectively depicted herein as rotors 202 and stators are collectively depicted herein as stators 204.

Optionally, as shown, the motor control arrangement 120 includes a rotor excitation unit 206 to couple electrical power from the battery arrangement 122 of the electrical vehicle 100 to a resonant inductive power coupling arrangement 208, wherefrom the electrical power is coupled wirelessly to the rotors 202 of the at least two electrical motors 116 and 118 for generating a rotor magnetic field that is operable to interact in operation with a commutated magnetic field of the stators 204 of the at least two electrical motors 116 and 118. In such an instance, the rotor excitation unit 206 is operable to convert a direct current from the battery arrangement 122 into an alternating current that is to be coupled to the resonant inductive power coupling arrangement 208. Such use of wireless resonant inductive power transfer within the at least two electrical motors 116 and 118 is highly innovative, for example via use of a subset of planar stator elements and correspondingly a subset of corresponding planar rotor elements, because a rectifier arrangement mounted on the rotors allows DC current to be generated on the rotors for generating a rotor magnetic field. This avoids in the at least two electrical motors 116 and 118 a need to utilize permanent magnets, for example rare-earth permanent magnets, that drastically reduces the cost of manufacturing the at least two electrical motors 116 and 118. Optionally, such resonant inductive power transfer to the rotors is implemented at a resonant frequency in a range of 50 kHz to 1 MHz.

Optionally, the rotor excitation unit 206 includes a resonant oscillator circuit (not shown), wherein the resonant oscillator circuit includes a tunable capacitor, a transformer including a primary winding and a secondary winding, and two push-pull transistors. In such an instance, the tunable capacitor and primary winding of the transformer constitute a tank circuit that is tunable to a resonant frequency. Optionally, the transformer is implemented as a compact ferrite ring core transformer. Furthermore, optionally, the two push-pull transistors are driven in mutual anti-phase at the resonant frequency of the resonant oscillator circuit. More optionally, the two push-pull transistors are implemented by way of silicon carbide transistors, although it will be appreciated that other types of solid state switching devices can be employed, for example D-MOS FETs, bipolar transistors, SCR's, thyristors and such like. Silicon carbide transistors are particular beneficial to employ because they are capable of switching large currents, for example in an order of 100 Amperes, with nanoseconds, while being able to withstand thereacross voltages in an order of 1000 Volts. More optionally, the resonant oscillator circuit of the rotor excitation unit 206 operates in a frequency range of 50 kilohertz to 1 megahertz, as aforementioned. In such an instance, a frequency of the alternating current that is to be coupled to the resonant inductive power coupling arrangement 208 lies within the aforesaid frequency range. Furthermore, optionally, a bypass capacitor (not shown) is provided across the rotor excitation unit 206, in order to remove stray alternating current noise within the direct current provided from the battery arrangement 122, and to allow for large peak stator commutation currents to be achieved when aforementioned digital commutation of the at least two electrical motors 116 and 118 is employed. Beneficially, use of such a bypass capacitor allows for purifying the direct current received by the rotor excitation unit 206 and consequently allows for purifying the alternating current that is to be coupled to the resonant inductive power coupling arrangement 208. Optionally, the resonant inductive power coupling arrangement 208 includes at least a capacitor and at least one inductor.

Furthermore, optionally, the rotors 202 of the at least two electrical motors 116 and 118 include a rectifier arrangement 210 for converting resonant inductively coupled power received at the rotors 202 into a direct current to generate the rotor magnetic field, as aforementioned. In such an instance, the rectifier arrangement 210 is operable to receive the alternating current (AC) from the resonant inductive power coupling arrangement 208 via inductive coupling therebetween, and convert such alternating current into the direct current (DC) that is subsequently employed to generate the rotor magnetic field. As an example, the rectifier arrangement 210 may provide the converted direct current to the electrical winding coil arrangements disposed on the one or more pkanar rotor elements of the rotors 202. Optionally, the rectifier arrangement 210 is implemented by way of a bridge rectifier, for example a Silicon bridge rectifier.

Moreover, optionally, as shown in FIG. 2, the motor control arrangement 120 includes a switching control unit 212 for switching commutation magnetizing currents supplied to the stators 204 of the at least two electrical motors 116 and 118 when in operation. In such an instance, the switching control unit 212 is operable to control a switching arrangement (not shown) for controlling the aforesaid magnetizing currents. It will be appreciated that the switching control unit 212 is operable to control which of the commutation windings (namely, the electrical winding coil arrangement disposed on the one or more planar stator elements of the stators 204) of the at least two electrical motors 116 and 118 are to be controlled and a manner of controlling such commutation windings of the at least two electrical motors 116 and 118. Such control allows a commutation rate and a magnitude of excitation currents applied in operation to the rotors and stators to be mutually independently controlled, for enable adaptive torque vs. rotation rates to be realized for the at least two electrical motors 116 and 118.

Optionally, the switching arrangement may be implemented by way of a plurality of silicon carbide transistors, for example as aforementioned. Optionally, at least one, for example both, of the at least two electrical motors 116 and 118 includes a regenerative braking coil arrangement (not shown) for generating electrical power from the at least two electrical motors 116 and 118 when regenerative braking is applied in operation to recharge the battery arrangement 122 of the electrical vehicle 100. In an exemplary implementation, the switching control unit 212 is operable to energize selectively the regenerative braking coil arrangement, i.e. implemented as phase coils P4, for generating electrical power from at least two electrical motors 116 and 118 when regenerative braking is applied in operation to recharge the battery arrangement 122 of the electrical vehicle 100. Specifically, the motor control arrangement 120 detects when regenerative braking is applied in operation, for example by employing a sensor element such as a potentiometer. The application of the regenerative braking allows a rotor of the at least two electrical motors 116 and 118 to remain energized, i.e. continue to draw electrical power from the battery arrangement 122, to generate a magnetic field. However, during regenerative braking, the phase windings PI, P2 and P3 (as described in a previous example) are not energized by their respective switching elements SI, S2, S3, and the rotor excitation unit 206 is coupled directly across the battery arrangement 122. Furthermore, during regenerative braking, a switching element S4 (which may be implemented as a bypass silicon carbide transistor) is activated to cause coils C of the rotor of the at least two electrical motors 116, 118to be energized, to generate power in the regenerative braking coil arrangement, i.e. implemented as the phase coils P4, of a stator of the at least two electrical motors 116, 118. For example, during the regenerative braking, the rotor of at least two electrical motors 116 and 118 remains energized, which causes the coils C of the rotor of at least two electrical motors 116 and 118 to generate a rotating magnetic field around the regenerative braking coil arrangement, i.e. the phase coils P4. This in turn causes induced power to be generated on the phase coils P4, which can subsequently be rectified (using rectifiers, not shown) for use in recharging the battery arrangement 122. In an example, this may be achieved using an isolating switched inverter charging circuit. Referring to FIG.3, there is shown an illustration of steps of a method 300 of providing motive torque in an electric vehicle (for example, such as the electric vehicle 100 of FIG. 1), in accordance with an embodiment of the present disclosure. At a step 302, an arrangement is made for an electrical motor arrangement to include at least two electrical motors (for example, such as the at least two electrical motors 116 and 118 shown in FIG. 1) for applying in operation torque to at least a pair of rear wheels. At a step 304, an arrangement is made for the at least two electrical motors to be mutually independently controllable from a motor control arrangement of the electric vehicle. At a step 306, an arrangement is made for the at least two electrical motors to be implemented as a sprung element of the vehicle frame arrangement and to be coupled via a coupling arrangement to their corresponding wheels.

The steps 302 to 306 are only illustrative and other alternatives can also be provided where one or more steps are added, one or more steps are removed, or one or more steps are provided in a different sequence without departing from the scope of the claims herein. Optionally, the method 300 includes arranging for the at least two electrical motors to include a casing; a stator mounted on the casing, the stator including 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; a rotor including (i) a shaft that is disposed within the central hole of each of the one or more planar stator elements of the stator and (ii) one or more planar (for example, radial plate-like) rotor elements attached to the shaft, wherein the one or more planar stator elements and the one or more planar rotor elements are associated with principal planes that are arranged mutually to abut with a magnetic separation gap therebetween, and the one or more planar stator and rotor elements are arranged to have electrical winding coil arrangements disposed thereon; and magnetic bearings coupled to ends of the shaft of the rotor. Optionally, the method 300 includes arranging for at least one of the at least two electrical motors to function as a digitally-commutated electrical motor, wherein, during commutation, current pulses are applied to commutation windings of the at least one electrical motor, and a freewheeling period is implemented between the current pulses during which the commutation windings are non-energized. Furthermore, optionally, the method 300 includes arranging for the motor control arrangement to include a rotor excitation unit to couple wirelessly electrical power from a battery arrangement to a resonant inductive power coupling arrangement, wherefrom the electrical power is coupled to the rotors of the at least two electrical motors for generating a rotor magnetic field that is operable to interact in operation with a commutated magnetic field of the stators of the at least two electrical motors. Moreover, optionally, the method 300 includes arranging for the motor control arrangement to include a rectifier arrangement for converting resonant inductively coupled power received at the rotors into a direct current to generate the rotor magnetic field. Optionally, the method 300 includes arranging for the rotors of the at least two electrical motors to be operable to rotate at a maximum rotation rate in a range of 30000 rotations per minute to 100000 rotations per minute. Furthermore, optionally, the method 300 includes arranging for the motor control arrangement to include a switching control unit for switching commutation magnetizing currents supplied to the stators of the at least two electrical motors when in operation. Moreover, optionally, the method 300 includes arranging for at least one of the at least two electrical motors to be coupled to a planetary gearbox arrangement for coupling a torque generated at the rotors to its corresponding wheel of the electrical vehicle. Optionally, in this regard the method 300 includes arranging for the planetary gearbox arrangement to include a cascaded configuration of a plurality of planetary gears. Optionally, the method 300 includes arranging for at least one of the at least two electrical motors to include a regenerative braking coil arrangement for generating electrical power from the at least one electrical motor when regenerative braking is applied in operation to recharge the battery arrangement of the electrical vehicle. Furthermore, optionally, the method 300 includes arranging for the electrical vehicle to include two front wheels and two rear wheels, wherein the two rear wheels are provided with corresponding two rear electrical motors mounted onto the vehicle frame arrangement, such that the two rear electrical motors are implemented as sprung mass of the electrical vehicle, and coupled to their respective wheels via a flexible torque- coupling arrangement. Optionally, the method 300 includes arranging for the motor control arrangement to be operable to apply differential torque between right-side wheels and left-side wheels of the electrical vehicle when the electrical vehicle executes turning maneuvers when in operation. Optionally, the method includes providing one or more steered front wheels of the electrical vehicle with in-hub electrical motors for providing additional motive power to the electrical vehicle; optionally, the in-hub electrical motors are implemented as aforementioned using one or more planar rotor elements, one or more planar stator elements, wireless resonant inductive power coupling of power to the rotor for generating a rotor magnetic field, and digital commutation of winding arrangements of the one or more stator elements.

It will be appreciated in the method that use of such wireless resonant inductive power coupling to the rotor for generating the rotor magnetic field potentially avoids the electrical motors needing to utilize permanent magnets, for example avoiding a need to employ permanent magnets fabricated from rare-earth elements, namely materials.

Optionally, the one or more planar rotor elements and the one or more stator elements include paramagnetic material, for example ferromagnetic material, for providing a low-reluctance magnetic path within the electrical motors. The ferromagnetic material is beneficially a ferrite material having a relative permeability (μ_Γ) in a range of 10 to 10000, more optionally in a range of 20 to 1000; such a ferrite beneficially exhibits a low electrical conductivity to reduce eddy current losses therein when exposed to a temporally changing magnetic field. Alternatively, or additionally, the ferromagnetic material is beneficially implemented as a laminated structure of thin steel plates, for example, silicon steel plates as commonly used for manufacturing electrical transformers. Optionally, the thin steel plates have an individual thickness in a range of 0.1 mm to 1.0 mm. Optionally, an insulating polymeric material, for example an adhesive epoxy, is provided between the steel plates to reduce eddy current conduction therebetween.

The present disclosure provides the aforementioned electrical vehicle and the aforementioned method of providing motive torque in such an electrical vehicle. The described electrical vehicle includes an improved electrical motor arrangement as compared to motor arrangements of conventional electrical vehicles. Specifically, the electrical motor arrangement described herein allows for reduction of overheating whilst providing high operational torque to the electrical vehicle. Furthermore, the described electrical motor arrangement is substantially lighter in weight as compared to its conventional counterparts, and also allows for balancing the electrical vehicle without requiring a separate differential element. Beneficially, the method of the present disclosure is simple, reliable, and easy to implement.

Referring to FIG. 4, there is shown a plan view illustration of an electrical vehicle 1100, in accordance with an embodiment of the present disclosure. The electrical vehicle 1100 includes a vehicle frame arrangement 1102, at least three wheels, depicted herein as wheels 1104, rotatably coupled onto the vehicle frame arrangement 1102, and an electrical motor arrangement 1106 for applying in operation torque to the at least three wheels 1104 to propel the electrical vehicle 1100 in a forward or a reverse direction. Throughout the present disclosure, the term "vehicle frame arrangement" relates to a physical frame or structure of the electrical vehicle 1100 to which various components (for example, such as an engine, a transmission, a drive shaft, a suspension and the like) are attached. Optionally, the vehicle frame arrangement 1102 includes a platform to which a suspension system of the electrical vehicle 1100 is coupled, and a transverse beam member disposed transversely (relative to an elongate axis of the vehicle frame arrangement 1102) at a location approximately mid-way along the vehicle frame arrangement 1102. More optionally, the vehicle frame arrangement 1102 includes an anti-roll bar. The anti-roll bar is operable, namely configured, to prevent the rolling of the electrical vehicle 1100 while taking sharp turns at a high speed. Furthermore, the at least three wheels 1104 are rotatably coupled to the vehicle frame arrangement 1102 via wheel axles. Throughout the present disclosure, the term "rotatably coupled" relates to circular movement of the at least three wheels around their corresponding axes. More optionally, the vehicle frame arrangement 1102 is coupled with wheel axles via a mechanical bearing arrangement. The wheel axles are further rotatably coupled to the at least three wheels 1104 of the electrical vehicle 1100.

In an embodiment, the electrical vehicle 1100 includes four wheels, namely two front wheels, depicted as front wheels 1104a, 1104c and two rear wheels, depicted as rear wheels 1104b, 1104d. The two front wheels 1104a, 1104c of the electrical vehicle 1100 are steered from a steering wheel 1114 of the electrical vehicle 1100. The steering wheel is optionally couple via power-assisted steering to the front wheels 1104a, 1104c. Optionally, the power-assisted steering is adaptive to driver preferences and/or to driving conditions.

Optionally, the front wheels 1104a, 1104c are associated with a front wheel suspension arrangement and the rear wheels 1104b, 1104d are associated with a rear wheel suspension arrangement. In such an instance, the vehicle frame arrangement 1102 of the electrical vehicle 1100 is provided with coil springs having a predetermined stiffness for the front wheel suspensions. The stiffness of the coil springs for the front wheel suspensions allows the suspensions to substantially compensate for the vertical movement (or "bounce") of the vehicle and provides a more comfortable driving experience for driver of the electrical vehicle 1100. Furthermore, optionally, the front wheels 1104a, 1104c and the rear wheels 1104b, 1104d are mounted on parallel herring-bone suspension with a spring and a damper arrangement (not shown). The damper arrangement is beneficially housed concentrically within the spring. In an example, the spring and damper arrangement may be implemented as an oil damper, a piezo-electric stack active damper, a magnetic rheological damper, or any combination of these. It will be appreciated that components of the spring and the damper arrangement are effective at mutually different frequency spectrum ranges, such that use of a combination of such spring and damper arrangements is capable of providing damping effectively over a greater frequency range, resulting in a more comfortable drive. For example, the magnetic rheological damper employs a magnetic-particle and oil mixture having at least an anti-coagulant, wherein damping characteristics of the magnetic rheological damper are optionally actively varied when driving to cope with different road surfaces and/or driver preferences. Optionally, the magnetic rheological damper employs an electromagnet to define its magnetizing field applied to aforementioned magnetic-particle and oil mixture. Alternatively, optionally, the magnetic rheological damper utilizes one or more permanent magnets whose magnetic coupling to the magnetic-particle and oil mixture is controlled by varying a magnetic path linking the one or more permanent magnets to the magnetic-particle and oil mixture.

Optionally, the spring and the damper arrangements of the front wheels 1104a, 1104c and the rear wheels 1104b, 1104d are mutually similar. Alternatively, optionally, the rear wheels 1104b, 1104d are provided with a simple oil-damper, whereas the front wheels 1104a, 1104c are provided with the magnetic rheological damper, whose operating characteristics can be adaptively varied depending upon driving conditions, travelling speed of the electrical vehicle 1100 and so forth.

Furthermore, the electrical motor arrangement 1106 includes at least three electrical motors, herein depicted as electrical motors 1108, 1110, 1112 for applying in operation torque to the at least three wheels 1104. The at least three electrical motors 1108-1112 receive electrical power from a battery arrangement 1116 of the electrical vehicle 1100. Specifically, the at least three electrical motors 1108-1112 are operable, namely configure, to provide a rotational force to the at least three wheels 1104 to produce a rotational motion therein. Optionally, output shafts of at least three electrical motors 1108-1112 are coupled via a corresponding gear arrangement to their corresponding wheel axles. Optionally, the gear arrangement is coupled to the rear wheels 1104b, 1104d via a flexible knuckle joint of the rear wheels 1104b, 1104d.

Furthermore, the at least three electrical motors 1108-1112 are mutually independently controllable from a motor control arrangement 1118 of the lelectrical vehicle 1100. The motor control arrangement 1118 may be hardware, software, a firmware or a combination thereof operable to control the operation of the at least three electrical motors 1108-1112 independently. For example, the motor control arrangement 1118 may provide different electrical power to each of the at least three electrical motors 1108-1112, based on the requirement of the electrical vehicle 1100. Furthermore, the motor control arrangement 1118 of the electrical vehicle 1100 is operable to control the torque provided by the at least three electrical motors 1108-1112 to the at least three wheels 1104. Optionally, the motor control arrangement 1118 includes a rotor excitation unit and a switching control unit (shown in FIG. 6) .

Additionally, at least one of the at least three electrical motors 1108- 1112 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) for example, such as the electric motor 1112. Specifically, the in- hub electrical motor 1112 is provided at a hub of at least one wheel of the at least three wheels, for example the front wheel 1104a. It will be appreciated that the in-hub electrical motor 1112 relates to an electric motor that is incorporated into the hub of a wheel and provides rotational movement to the wheel directly. The in-hub electrical motor 1112 is operable to apply, in operation, torque to its corresponding wheel . For example, the in-hub electrical motor 1112 is operable to provide the in operation torque to the front wheel 1104a when mounted thereupon. Optionally, the in-hub electrical motor 1112 is implemented on the front wheels 1104b of the electrical vehicle 1100. Optionally, the in-hub electrical motor 1112 has a size that is relatively smaller than a size of other electrical motors employed to propel the electrical vehicle 1100 (for example, such as electrical motors 1108 and 1110).

Furthermore, additionally, at least one of the at least three electrical motors, for example, such as electrical motors 1108 or 1110, is implemented as a sprung element of the vehicle frame arrangement 1102 and is coupled via a coupling arrangement 1120 to its corresponding wheel . 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 the wheel suspensions. Furthermore, the at least one of the at least three electrical motors 1108- 1110 is mounted on the vehicle frame arrangement 1102. Since a mass of the vehicle frame arrangement 1102 is supported by the wheel suspensions or spring and damper arrangement, the mass of the at least one of the at least three electrical motors 1108-1110 is also 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 at least one of the at least three electrical motors 1108 or 1110 to corresponding wheels. Optionally, the coupling arrangement 1120 includes a clutch member and a gearbox arrangement. The output shaft of the at least one of the at least three electrical motors 1108 or 1110 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 to the two rear wheels 1104b and 1104d. The gearbox arrangement includes a gearbox shaft for driving the at least one of the at least three wheels 1104 for propelling the electrical vehicle 1100 when in operation. Optionally, when the gearbox arrangement is operated in an automatic transmission, namely continuously-variable torque converter, the clutch member is less used, but nevertheless coordinated with operation of the continuously-variable torque converter to avoid any slippage occurring within the clutch member. Alternatively, when the gearbox arrangement is operated in a manual transmission, discrete gear ratios are provided in the gearbox arrangement.

As described above, the electrical vehicle 1100 includes the two front wheels 1104a, 1104c and the two rear wheels 1104b, 1104d. In an embodiment, the two front wheels 1104a, 1104c are provided with corresponding in-hub electrical motors 1112, and the two rear wheels 1104b, 1104d are provided with corresponding two rear electrical motors 1108 and 1110 mounted onto the vehicle frame arrangement 1102, such that the two rear electrical motors 1108 and 1110 are implemented as a sprung mass of the electrical vehicle 1100, and coupled to their respective wheels via a flexible torque-coupling arrangement (for example, such as coupling arrangement 1120). In such an embodiment, the electrical vehicle 1100 includes four electrical motors, for example such as electrical motors 1108-1112, wherein four electrical motors 1108-1112 comprises two in-hub electrical motors 1112 and two rear electrical motors 1108 and 1110. Furthermore, optionally, the two in-hub electrical motors 1112 are provided for applying the torque to the two front wheels 1104a, 1104c and the two rear electrical motors 1108 and 1110 are provided for applying the torque the two rear wheels 1104b, 1104d of the electrical vehicle 1100. Additionally, optionally, the two in-hub electrical motors 1112 are implemented in corresponding hubs of the electrical vehicle 1100. The two in-hub electrical motors 1112 are operable to directly transmit the torque, from the two in-hub electrical motors 1112, to the two front wheels 1104a, 1104c.

Furthermore, optionally, in order to implement the two rear electrical motors 1108 and 1110 as a sprung element of the electrical vehicle 1100, the two rear electrical motors 1108 and 1110 are mounted on the vehicle frame arrangement 1102. Thus, a mass of the two rear electrical motors 1108 and 1110 is supported by the wheel suspensions or spring and damper arrangement. Additionally, optionally, the two rear electrical motors 1108 and 1110 are operable to transmit the torque, from the two rear electrical motors 1108 and 1110, to the two rear wheels 1104b, 1104d. Specifically, in such an embodiment, the two rear electrical motors 1108 and 1110 are coupled to the flexible torque- coupling arrangement for transmitting the torque to the two rear wheels 1104b, 1104d of the electrical vehicle 1100. Optionally, the flexible torque-coupling arrangement includes two torque coupling members, each for the two rear wheels 1104b, 1104d. More optionally, the flexible torque-coupling may be provided by using jaw type couplings, Oldham Coupling and/or universal joints. Beneficially, using such a flexible torque-coupling arrangement accommodates misalignment between the output shafts of the two rear electrical motors during different load conditions. Optionally, for a given rear wheel 1104b, 1104d, the two rear electrical motors 1108 and 1110 and its associated gearbox arrangement are implemented as an in-hub arrangement. Optionally, the motor control arrangement 1118 is further operable to apply a forwardly-directed traction force to one or more electrical motors associated with one or more front wheels of the electrical vehicle 1100 and a backwardly-directed retarding traction force to one or more electrical motors of one or more rear wheels of the electrical vehicle 1100 to straighten-up a forward trajectory of the electrical vehicle 1100 when driving on slippery road surfaces, for example to enable to the electrical vehicle 1100 to recover from a spinning trajectory on icy, snowy or wet road surfaces. Optionally, the motor control arrangement 1118, based upon the driver's actuation of an accelerator pedal, a brake pedal and (optionally) a gear lever, and a steering angle of the steering wheel of the electrical vehicle 1100, selectively delivers electrical power to the two in-hub electrical motors (for example, such as two in-hub electrical motors 1112, shown in FIG. 4) to generate forwardly-directed traction force in the front wheel 1104a and 1104c. Furthermore, the motor control arrangement 1118, based upon the driver's actuation of an accelerator pedal, a brake pedal and (optionally) a gear lever, and steering angle of the steering wheel of the electrical vehicle 1100 selectively delivers electrical power to the two rear electrical motors (for example, such as two rear electrical motors 1108 and 1110, shown in FIG. 4) to generate backwardly-directed retarding traction force in the rear wheels 1104b and 1104a. For example, in an event wherein the electrical vehicle 1100 is operating in a wet, snowy or icy condition, for example as aforementioned, the motor control arrangement 1118 is operable to provide a high electrical power to the two in-hub electrical motors 1112 associated with the front wheel 1104a and 1104c to generate a forwardly-directed traction force in order to straighten up the electrical vehicle to a direction in which the electrical vehicle 1100 was travelling prior to experiencing a spinning motion in aforesaid wet, snowy or icy condition. Furthermore, optionally, the motor control arrangement 1118 is operable, namely configured, to generate a differential torque between right-side wheel 1104c, 1104d and left-side wheels 1104a, 1104b of the electrical vehicle 1100 when the electrical 1100 vehicle executes turning maneuvers is use. Throughout the present disclosure, the term "differential torque", as used herein, relates to providing different amounts of toque to the different wheels of the electrical vehicle 1100. Optionally, in an event wherein the electrical vehicle 1100 is maneuvered in a left direction, the motor control arrangement 1118 is configured to control the electrical power provided to the left-side front wheel 1104a and the right-side front wheel 1104c. In such instance, the motor control arrangement 1118 is configured to provide more electrical power to the right-side front wheel 1104c in order to generate more torque therein, as compared to the left-side front wheel 1104a. Optionally, in an event wherein the electrical vehicle 1100 is maneuvered in a right direction the motor control arrangement 1118 is configured to control the electrical power provided to the left-side front wheel 1104a and the right-side front wheel 1104c. In such instance, the motor control arrangement 1118 is configured to provide more electrical power to the left-side front wheel 1104a in order to generate more torque therein, as compared to the right-side front wheel 1104c.

Referring to FIG. 5, there is shown a block diagram of the battery arrangement 1116 of an electrical vehicle 1100, in accordance with an embodiment of the present disclosure. As show, optionally, the battery arrangement 1116 includes a first battery unit 1202 and a second battery unit 1204, wherein the first battery unit 1202 is operable to electrical provide power to the two rear electrical motors (for example, such as two rear electrical motors 1108 and 1110, shown in FIG. 4) of the electrical vehicle (for example, such as electrical vehicle 1100, shown in FIG. 4) and the second battery unit 1204 is operable to provide electrical power to the two in-hub electrical motors (for example, such as two in-hub electrical motors 1108 and 1110, shown in FIG. 4) of the electrical vehicle. Moreover, optionally, the first battery unit 1202 is implemented as a floor-mounted flat battery unit, or an L-shaped battery unit mounted behind seat of driver. Furthermore, optionally, the second battery unit 1204 is mounted in proximity of the two in-hub electrical motors of the electrical vehicle. Optionally, the battery arrangement 1116 is supplemented with supercapacitors for providing for peaks in current demand. The first battery unit 1202 is operable to store a relatively larger amount of the electric power than the second battery unit 1204. In an embodiment, the first battery unit 1202 and the second battery unit 1204 are coupled with the motor control arrangement (for example, such as motor control arrangement 1118, shown in FIG. 4). In such a case, the motor control arrangement is operable to control the amount of electric power provided by the first battery unit 1202 and the second battery unit 1204. In an example, when more electrical power is required for the two in-hub electrical motors, the motor control arrangement provides controls the second battery unit 1204 to provide more electrical power.

Optionally, each of the at least three electrical motors (for example, such as electrical motor 1108, 1110 and 1112, shown in FIG. 4) is manufactured to be accommodated in a corresponding casing (not shown). In one example, the casing is implemented as a hollow cylindrical structure that is operable to accommodate the components of its corresponding electrical motor, namely at least one of the electrical motors 1108, 1110 and 1112. In another example, the casing is implemented as a hollow cylindrical structure including a plurality of cylindrical portions, for example two semi-cylindrical halves. In such an instance, the semi-cylindrical halves are operable to be arranged along a mutually abutting surface thereof, for example a planar surface thereof, to provide the casing. It will be appreciated that such an implementation of the casing including the semi-cylindrical halves enables convenient assembly (and/or disassembly) of each of the at least three electrical motors 1108, 1110 and 1112 by enabling easy arrangement of the components of the each of the at least three electrical motors 1108, 1110 and 1112 therein. Furthermore, optionally, a stator (shown in FIG. 6) is mounted on the casing. The stator is a stationary component of the each of the at least three electrical motors 1108, 1110 and 1112. Furthermore, the stator is operable to provide a magnetic field to enable operation of one or more components of the each of the at least three electrical motors 1108, 1110 and 1112. Moreover, optionally, the stator includes one or more planar stator elements, for example one or more radial plate-like elements, (not shown) extending from the casing, wherein each of the one or more planar elements includes a central hole. In an example, the one or more planar stator elements are attached to an inside of the casing. In one example, the one or more planar stator elements are each implemented as a pair of semi-circular half plates that are operable to be arranged to form the one or more planar stator elements. Additionally, optionally, the one or more planar stator elements includes a central hole that enables one or more components (such as a shaft) of the each of the at least three electrical motor 1108, 1110 and 1112 to be accommodated therein.

Furthermore, optionally, each of the at least three electrical motors 108, 1110 and 1112 includes the rotor (shown in FIG. 6) including the shaft (not shown) 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 (not shown), for example radial plate-like elements, attached to the shaft. Specifically, the rotor is a rotatable component of the each of the at least three electrical motors 1108, 1110 and 1112 that enables to generate torque, for example, for rotating one or more wheels associated with the electrical vehicle 1100. In an embodiment, the rotors of the at least three electrical motors 1108, 1110 and 1112 are operable to rotate at a maximum rotation rate in a range of 30000 rotations per minute to 100000 rotations per minute. It will be appreciated that such a high rotation rate of the rotors enables a high speed operation of the each of the at least three electrical motors 1108, 1110 and 1112. For example, such high rotation rate of the rotors enables high rate of change of flux associated with the magnetic field provided by the stators. Additionally, optionally, the shaft of the rotor is implemented as a cylindrical structure that is operable to rotate around an axis (such as an axis passing through center of the cylindrical shaft). Furthermore, the rotor includes one or more planar rotor elements attached to the shaft. Furthermore, the one or more planar rotor elements are attached to the shaft of the rotor along the axis thereof.

In such a case, the one or more planar stator elements and the one or more planar rotor elements are associated with corresponding principal planes that are arranged mutually to abut with a magnetic separation gap therebetween. For example, the one or more planar rotor elements are attached to the 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 re disposed in a gap formed between corresponding two adjacent planar stator elements. It will be appreciated that 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 a distance between principal surface planes of the one or more planar stator elements and the one or more planar stator elements.

Moreover, optionally, the one or more planar stator and 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, each of the at least three electrical motors 1108, 1110 and 1112 includes magnetic bearings (not shown) coupled to ends of the shaft of the rotor. 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, namely are configured, to prevent physical contact between the shaft and one or more other components of the at least one electrical motors 1108, 1110 or 1112, such as, the one or more planar stator elements.

Additionally, optionally, at least one of the at least three electrical motors (for example, such as electrical motor 1108, 1110 or 1112, shown in FIG. 4) is operable to function as a digitally-commutated electrical motor.

High-performance compact digital motors, namely "digitally-commutated motors", are known for use in portable electrical appliances, for example portable vacuum cleaners and hair driers. Such compact digital motors are described, for example, in a published patent document WO2010/112930 A2 ^High-speed electric system", applicant - Dyson Technology Ltd., UK) . These high-performance compact digital motors employ rare-earth permanent magnets. Principles of digital commutation for electrical motors as described in the published patent document are hereby incorporated by reference. Specifically, digital commutation is provided to generate motion in the at least one electrical motor 1108, 1110 or 1112. Furthermore, digital commutation may be implemented using digitally controlled current pulses. Furthermore, optionally, during commutation, current pulses are applied to commutation windings of the at least one electrical motor 1108, 1110 or 1112, and a free-wheeling period is implemented between the current pulses during which the commutation windings are non-energized. Specifically, the commutation winding of the at least one electrical motor 1108, 1110 or 1112 may comprise an electrical winding coil arrangement (not shown) disposed on the one or more planar stator elements of the stator. In exemplary implementation, the current pulses may be provided to a phase coil PI of the commutation winding using the switching control unit, specifically, a switching element SI to generate a motion in the rotor. Subsequently, the current pulse may be switched to a phase coil P2 of commutation winding using a switching element S2 to sustain the generated motion. Furthermore, the current pulses may be switched continuously from phase coil PI to P2, P2 to P3 and subsequently, P3 to PI to maintain rotational motion of the at least one electrical motor 1108, 1110 or 1112. Specifically, the phase coils PI, P2 and P3 are beneficially energized in sequence as the rotor rotates, and the coils PI, P2 and P3 are not energized simultaneously, namely only one commutated phase is energized at any given time. Therefore, a free^¬ wheeling period may be implemented between the switching of current between the aforementioned phase coils. Optionally, the at least one of the at least three electrical motors 1108 or 1110 are coupled to a planetary gearbox arrangement for coupling a torque generated at the rotors to its corresponding wheel of the electrical vehicle 1100. In an embodiment, the output shaft of the at least one of the at least three electrical motors 1108 or 1110 is directly coupled to the planetary gearbox arrangement, wherein the planetary gearbox arrangement is configured for providing a geared output torque. The planetary gearbox arrangement further includes an output shaft for driving the at least one of the at least three wheels 1104 for propelling the electrical vehicle 1100 when in operation. Beneficially, the planetary gearbox arrangement provides multiple gear ratios from a compact size of gearbox casing. Furthermore, in such an implementation, use of planetary gearbox arrangement allows for low transmission losses. In another embodiment, the output shaft of the at least one of the at least three electrical motors 1108 or 1110 is coupled to a clutch member. The clutch member is further coupled to the planetary gearbox arrangement. Thereafter, the planetary gearbox arrangement transfers the geared output torque to the at least one of the at least three wheels 1104 for propelling the electrical vehicle 1100 when in operation. Optionally, cog wheels of the planetary gear arrangement are manufactured using advanced 3D printing techniques for metal powder sintering of printed shapes, or by using hydraulically-pressed sintered metal construction.

Furthermore, optionally, the planetary gearbox arrangement includes a cascaded configuration of a plurality of planetary gears. Throughout the present disclosure the term "cascaded configuration", used herein, relates to an arrangement of the plurality of planetary gears in a sequential adjoining and compact manner. Beneficially, the cascaded configuration of a plurality of planetary gears allows for a light weight and a compact size of the coupling arrangement.

Referring to FIG. 6, there is shown a block diagram depicting components of the electrical vehicle (for example, such as electrical vehicle 1100, shown in FIG. 4), in accordance with an embodiment of the present disclosure. As shown, the electrical vehicle 1100 includes the battery arrangement 1116, the motor control arrangement 1118, and the electrical motor arrangement 1106. As mentioned previously, the electrical motor arrangement 1106 includes the at least three electrical motors 1108, 1110 and 1112 whose rotors are collectively depicted herein as rotors 1302 and stators are collectively depicted herein as stators 1304.

Optionally, as shown, the motor control arrangement 1118 includes a rotor excitation unit 1306 to couple electrical power from the battery arrangement 1116 of the electrical vehicle 1100 to a resonant inductive power coupling arrangement 1308, wherefrom the electrical power is coupled wirelessly to the rotors 1302 of the at least three electrical motors 1108, 1110 and 1112 for generating a rotor magnetic field that is operable to interact in operation with a commutated magnetic field of the stators 1304 of the at least three electrical motors 1108, 1110 and 1112. In such an instance, the rotor excitation unit 306 is operable to convert a direct current (DC) from the battery arrangement 1116 into an alternating current (AC) that is to be coupled to the resonant inductive power coupling arrangement 1308. Optionally, the rotor excitation unit 1306 includes a resonant oscillator circuit (not shown), wherein the resonant oscillator circuit includes a tunable capacitor, a transformer including a primary winding and a secondary winding, and two push-pull transistors. In such an instance, the tunable capacitor and primary winding of the transformer constitute a tank circuit that is tunable to a resonant frequency. Optionally, the transformer is implemented as a compact ferrite ring core transformer. Furthermore, optionally, the two push-pull transistors are driven in mutual anti-phase at the resonant frequency of the resonant oscillator circuit. More optionally, the two push-pull transistors are implemented by way of solid state switching devices, for example silicon FET's, silicon D- MOS FET's, silicon bipolar transistors, thyristors, SCR's, silicon carbide transistors. Silicon carbide transistors are especially suitable because they are able to switch large currents, for example 100 Amperes, with a switching time of nanoseconds whilst being able to withstand voltage potentials of up to 1000 Volts; moreover, such silicon carbide transistors are less prone to thermal runaway in comparison to other types of silicon solid state switching devices.

More optionally, the resonant oscillator circuit of the rotor excitation unit 1306 operates in a frequency range of 50 kilohertz to 1 megahertz. In such an instance, a frequency of the alternating current (AC) that is to be coupled to the resonant inductive power coupling arrangement 1308 lies within the aforesaid frequency range. A subset of the planar stator elements and the planar rotor elements are allocated for wirelessly coupling, via use of aforementioned resonant inductive power coupling, power to the rotor, for example by employing suitable winding arrangements disposed thereonto.

Furthermore, optionally, a bypass capacitor (not shown) is provided across the rotor excitation unit 1306, in order to remove stray alternating current noise within the direct current provided from the battery arrangement 1116, and to enable high peak currents in phases PI, P2 and P3 to be achieved when implementing digital commutation, as aforementioned. Beneficially, use of such a bypass capacitor allows for purifying the direct current received by the rotor excitation unit 1306 and consequently allows for purifying the alternating current that is to be coupled to the resonant inductive power coupling arrangement 1308.

Optionally, the resonant inductive power coupling arrangement 1308 includes at least a capacitor and at least one inductor.

Furthermore, optionally, the rotors 1302 of the at least three electrical motors 1108, 1110 and 1112 include a rectifier arrangement 1310 for converting resonant inductively coupled power received at the rotors 302 into a direct current (DC) to generate the rotor magnetic field. In such an instance, the rectifier arrangement 1310 is operable to receive the alternating current (AC) from the resonant inductive power coupling arrangement 1308 via wireless inductlive coupling therebetween, and convert such alternating current (AC) into the direct current (DC) that is subsequently employed to generate the rotor magnetic field. As an example, the rectifier arrangement 1310 may provide the converted direct current (DC) to the electrical winding coil arrangements disposed on the one or more planar rotor elements of the rotors 1302. Optionally, the rectifier arrangement 1310 is implemented by way of a silicon bridge rectifier.

Moreover, optionally, as shown in FIG. 6, the motor control arrangement 1118 includes a switching control unit 1312 for switching commutation magnetizing currents supplied to the stators 1304 of the at least three electrical motors 1108, 1110 and 1112 when in operation. In such an instance, the switching control unit 1312 is operable to control a switching arrangement (not shown) for controlling the aforesaid magnetizing currents. It will be appreciated that the switching control unit 1312 is operable to control which of the commutation windings (namely, the electrical winding coil arrangement disposed on the one or more radial plate-like stator elements of the stators 1304) of the at least three electrical motors 1108, 1110 and 1112 are to be controlled and a manner of controlling such commutation windings of the at least three electrical motors 1108, 1110 and 1112.

Optionally, the switching arrangement may be implemented by way of a plurality of silicon carbide transistors, for example as aforementioned.

Optionally, the at least one of the at least three electrical motors 1108, 1110 or 1112 includes a regenerative braking coil arrangement (not shown) for generating electrical power from the at least one electrical motor (for example, such as electrical motor 1112) when regenerative braking is applied in operation to recharge the battery arrangement 1116 of the electrical vehicle 1100. In an exemplary implementation, the switching control unit 1312 is operable to selectively energize the regenerative braking coil arrangement, i .e. implemented as phase coils P4, for generating electrical power from at least one electrical motor (for example, such as the electrical motor 1112) when regenerative braking is applied in operation to recharge the battery arrangement 1116 of the electrical vehicle 1100. Specifically, the motor control arrangement 118 detects when regenerative braking is applied in operation, for example, with the help of an electronic sensor such as a potentiometer. The application of the regenerative braking allows a rotor of the at least one electrical motor (for example, such as the electrical motor 1112) to remain energized, i .e. continue to draw electrical power from the battery arrangement 1116, to generate a magnetic field. However, during regenerative braking, the phase windings PI, P2 and P3 (as described in a previous example) are not energized by their respective switching elements SI, S2, S3, and the rotor excitation unit 1306 is coupled directly across the battery arrangement 1116. Furthermore, during regenerative braking, a switching element S4 (which may be implemented as a bypass silicon carbide transistor) is activated to cause coils C of the rotor of the at least one electrical motor to be energized, to generate power in the regenerative braking coil arrangement, i .e. implemented as the phase coils P4, of a stator of the at least one electrical motor 1112. For example, during the regenerative braking, the rotor of the at least one electrical motor remains energized, which causes the coils C of the rotor of the at least one electrical motor to generate a rotating magnetic field around the regenerative braking coil arrangement, i .e. the phase coils P4. This in turn causes induced power to be generated on the phase coils P4, which can subsequently be rectified (using rectifiers, not shown) for use in recharging the battery arrangement 1116. In an example, this may be achieved using an isolating switched inverter charging circuit.

Referring to FIG.7, there is shown an illustration of steps of a method 1400 of providing motive torque in an electric vehicle (for example, such as the electric vehicle 1100 of FIG. 4), in accordance with an embodiment of the present disclosure. At a step 1402, an arrangement is made for an electrical motor arrangement to include at least three electrical motors for applying in operation torque to the at least three wheels. At a step 1404, an arrangement is made for the at least three electrical motors to be mutually independently controllable from a motor control arrangement of the electric vehicle. At a step 1406, an arrangement is made for at least one of the at least three electrical motors to be implemented as an in-hub electrical motor. At a step 1408, an arrangement is made for at least one of the at least three electrical motors to be implemented as a sprung element of the vehicle frame arrangement and to be coupled via a coupling arrangement to its corresponding wheel.

The steps 1402 to 1408 are only illustrative and other alternatives can also be provided where one or more steps are added, one or more steps are removed, or one or more steps are provided in a different sequence without departing from the scope of the claims herein. Optionally, the method 1400 includes arranging for the at least three electrical motors to include a casing; a stator mounted on the casing, the stator including 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; a rotor including (i) a shaft that is disposed within the central hole of each of the one or more planar stator elements of the stator and (ii) one or more planar, for example radial plate-like, rotor elements attached to the shaft, wherein the one or more planar stator elements and the one or more planar rotor elements are associated with principal planes that are arranged mutually to abut with a magnetic separation gap therebetween, and the one or more planar stator and rotor elements are arranged to have electrical winding coil arrangements disposed thereon; and magnetic bearings coupled to ends of the shaft of the rotor. More optionally, the method 1400 includes arranging for at least one of the at least three electrical motors to function as a digitally-commutated electrical motor, for example as aforementioned, wherein, during commutation, current pulses are applied to commutation windings of the at least one electrical motor, and a free-wheeling period is implemented between the current pulses during which the commutation windings are non-energized. Furthermore, optionally, the method 1400 includes arranging for the motor control arrangement to include a rotor excitation unit to couple electrical power from a battery arrangement to a resonant inductive power coupling arrangement, wherefrom the electrical power is coupled wirelessly to the rotors of the at least three electrical motors for generating a rotor magnetic field that is operable to interact in operation with a commutated magnetic field of the stators of the at least three electrical motors. Moreover, optionally, the method 1400 includes arranging for the motor control arrangement to include a rectifier arrangement for converting resonant inductively coupled power received at the rotors into a direct current to generate the rotor magnetic field.

Optionally, the method 1400 includes arranging for the rotors of the at least three electrical motors to be operable to rotate at a maximum rotation rate in a range of 30000 rotations per minute to 100000 rotations per minute. Furthermore, optionally, the method 1400 includes arranging for the motor control arrangement to include a switching control unit for switching commutation magnetizing currents supplied to the stators of the at least three electrical motors when in operation. Moreover, optionally, the method 1400 includes arranging for at least one of the at least three electrical motors to be coupled to a planetary gearbox arrangement for coupling a torque generated at the rotors to its corresponding wheel of the electrical vehicle. More optionally, the method 1400 includes arranging for the planetary gearbox arrangement to include a cascaded configuration of a plurality of planetary gears. Optionally, the method 1400 includes arranging for at least one of the at least three electrical motors to include a regenerative braking coil arrangement for generating electrical power from the at least one electrical motor when regenerative braking is applied in operation to recharge the battery arrangement of the electrical vehicle. Furthermore, optionally, the method 1400 includes arranging for the electrical vehicle to include two front wheels provided with corresponding in-hub electrical motors, and two rear wheels provided with corresponding two rear electrical motors mounted onto the vehicle frame arrangement, such that the two rear electrical motors are implemented as sprung mass of the electrical vehicle, and coupled to their respective wheels via a flexible torque-coupling arrangement. Optionally, in this regard, the method 1400 includes arranging for the battery arrangement to include a first battery unit and a second battery unit, wherein the first battery unit is operable for providing electrical power to the two rear electrical motors of the electrical vehicle and the second battery unit is operable for providing electrical power to the two in-hub electrical motors of the electrical vehicle. Furthermore, optionally, the method 1400 includes arranging for the electrical motor control arrangement to be operable to execute at least one of: (a) applying a forwardly-directed traction force to one or more electrical motors associated with one or more front wheels of the electrical vehicle and a backwardly-directed retarding traction force to one or more electrical motors of one or more rear wheels of the electrical vehicles to straighten-up a forward trajectory of the electrical vehicle when driving on slippery road surfaces; and (b) applying differential torque between right-side and left-side wheels of the electrical vehicle when the electrical vehicle executes turning maneuvers when in operation.

The present disclosure provides the aforementioned electrical vehicle and the aforementioned method of providing motive torque in such an electrical vehicle. The described electrical vehicle includes an improved electrical motor arrangement as compared to motor arrangements of conventional electrical vehicles. Specifically, the electrical motor arrangement described herein allows for reduction of overheating whilst providing high operational torque to the electrical vehicle. Furthermore, the described electrical motor arrangement is substantially lighter in weight as compared to its conventional counterparts, and also allows for balancing the electrical vehicle without requiring a separate differential element. Beneficially, the method of the present disclosure is simple, reliable, and easy to implement. Moreover, the electrical motor arrangement described herein provides high power to aid on electric- driven acceleration. Additionally, the described electrical motor arrangement allows for variable torque to be provided to wheel of the electrical motor.

Importantly, the described electrical motor arrangement is susceptible to being implemented without needing to include permanent magnets on stators and rotors thereof, for example rare-earth elements such as neodymium, thereby allowing for considerable manufacturing cost reduction. Optionally, the planar rotor and stator elements employ paramagnetic materials therein for providing a low reluctance magnetic path for generated magnetic fields, to improve electrical motor performance. Such paramagnetic materials beneficially include ferromagnetic materials, for example ferrites and laminated steel sheets, for example laminated silicon steel sheets.

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. An electrical vehicle including a vehicle frame arrangement, at least one front wheel and a pair of rear wheels rotatably coupled onto the vehicle frame arrangement, and an electrical motor arrangement for applying in operation torque to at least the pair of rear wheels to propel the electrical vehicle in a forward or a reverse direction, characterized in that:

(iii) the at least two electrical motors are implemented as a sprung element of the vehicle frame arrangement and are coupled via a coupling arrangement to their corresponding wheels.

2. An electrical vehicle of claim 1, characterized in that each of the at least two electrical motors 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;

- a rotor including

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

- magnetic bearings coupled to ends of the shaft of the rotor.

3. An electrical vehicle of claim 2, characterized in that the planar elements are implemented as radial plate-like elements.

4. An electrical vehicle of claim 2 or 3, characterized in that at least one of the at least two electrical motors is operable to function as a digitally-commutated electrical motor, wherein, during commutation, current pulses are applied to commutation windings of the at least one electrical motor, and a free-wheeling period is implemented between the current pulses during which the commutation windings are non- energized.

5. An electrical vehicle of claims 2, 3 or 4, characterized in that the motor control arrangement includes a rotor excitation unit to couple electrical power wirelessly from a battery arrangement of the electrical vehicle to a resonant inductive power coupling arrangement, wherefrom the electrical power is coupled to the rotors of the at least two electrical motors for generating a rotor magnetic field that is operable to interact in operation with a commutated magnetic field of the stators of the at least two electrical motors.

6. An electrical vehicle of claims 2, 3, 4 or 5, characterized in that the rotors of the at least two electrical motors include a rectifier arrangement for converting resonant inductively coupled power received at the rotors into a direct current (DC) to generate the rotor magnetic field.

7. An electrical vehicle of any one of claims 2 to 6, characterized in that the rotors of the at least two electrical motors are operable to rotate at a maximum rotation rate in a range of 30000 rotations per minute to 100000 rotations per minute.

8. An electrical vehicle of any one of claims 2 to 7, characterized in that the motor control arrangement includes a switching control unit for switching commutation magnetizing currents supplied to the stators of the at least two electrical motors when in operation.

9. An electrical vehicle of any one of claims 2 to 8, characterized in that at least one of the at least two electrical motors are coupled to a planetary gearbox arrangement for coupling a torque generated at the rotors to its corresponding wheel of the electrical vehicle.

10. An electrical vehicle of claim 9, characterized in that the planetary gearbox arrangement includes a cascaded configuration of a plurality of planetary gears.

11. An electrical vehicle of any one of the preceding claims, characterized in that at least one of the at least two electrical motors includes a regenerative braking coil arrangement for generating electrical power from the at least one electrical motor when regenerative braking is applied in operation to recharge the battery arrangement of the electrical vehicle.

12. An electrical vehicle of any one of the preceding claims, characterized in that the electrical vehicle includes two front wheels and two rear wheels, wherein the two rear wheels are provided with corresponding two rear electrical motors mounted onto the vehicle frame arrangement, such that the two rear electrical motors are implemented as sprung mass of the electrical vehicle, and coupled to their respective wheels via a flexible torque-coupling arrangement.

13. An electrical vehicle of any one of the preceding claims, wherein the motor control arrangement is operable (configured) to apply differential torque between right-side wheels and left-side wheels of the electrical vehicle when the electrical vehicle executes turning maneuvers when in operation.

14. A method of providing motive torque in an electrical vehicle including a vehicle frame arrangement, at least one front wheel and a pair of rear wheels rotatably coupled onto the vehicle frame arrangement, and an electrical motor arrangement for applying in operation torque to at least the pair of rear wheels to propel the electrical vehicle in a forward or a reverse direction, characterized in that the method includes:

15. A method of claim 14, characterized in that the method includes arranging for the at least two electrical motors to include:

- 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; - a rotor including

- one or more planar rotor elements attached to the shaft;

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

- magnetic bearings coupled to ends of the shaft of the rotor.

16. A method of claim 15, characterized in that the method includes arranging for at least one of the at least two electrical motors to function as a digitally-commutated electrical motor, wherein, during commutation, current pulses are applied to commutation windings of the at least one electrical motor, and a free-wheeling period is implemented between the current pulses during which the commutation windings are non-energized.

17. A method of claim 15 or 16, characterized in that the method includes arranging for the motor control arrangement to include a rotor excitation unit to couple wirelessly electrical power from a battery arrangement to a resonant inductive power coupling arrangement, wherefrom the electrical power is coupled to the rotors of the at least two electrical motors for generating a rotor magnetic field that is operable to interact in operation with a commutated magnetic field of the stators of the at least two electrical motors.

18. A method of claims 15, 16 or 17, characterized in that the method includes arranging for the motor control arrangement to include a rectifier arrangement for converting resonant inductively coupled power received at the rotors into a direct current to generate the rotor magnetic field.

19. A method of any one of claims 15 to 18, characterized in that the method includes arranging for the rotors of the at least two electrical motors to be operable to rotate at a maximum rotation rate in a range of 30000 rotations per minute to 100000 rotations per minute.

20. A method of any one of claims 15 to 19, characterized in that the method includes arranging for the motor control arrangement to include a switching control unit for switching commutation magnetizing currents supplied to the stators of the at least two electrical motors when in operation.

21. A method of any one of claims 15 to 20, characterized in that the method includes arranging for at least one of the at least two electrical motors to be coupled to a planetary gearbox arrangement for coupling a torque generated at the rotors to its corresponding wheel of the electrical vehicle.

22. A method of claim 21, characterized in that the method includes arranging for the planetary gearbox arrangement to include a cascaded configuration of a plurality of planetary gears.

23. A method of any one of claims 14 to 22, characterized in that the method includes arranging for at least one of the at least two electrical motors to include a regenerative braking coil arrangement for generating electrical power from the at least one electrical motor when regenerative braking is applied in operation to recharge the battery arrangement of the electrical vehicle.

24. A method of any one of the claims 14 to 23, characterized in that the method includes arranging for the electrical vehicle to include two front wheels and two rear wheels, wherein the two rear wheels are provided with corresponding two rear electrical motors mounted onto the vehicle frame arrangement, such that the two rear electrical motors are implemented as sprung mass of the electrical vehicle, and coupled to their respective wheels via a flexible torque-coupling arrangement.

25. A method of any one of the claims 14 to 24, characterized in that the method includes arranging for the motor control arrangement to be operable to apply differential torque between right-side wheels and leftside wheels of the electrical vehicle when the electrical vehicle executes turning maneuvers when in operation.

26. An electric vehicle including a vehicle frame arrangement, at least three wheels rotatably coupled onto the vehicle frame arrangement, and an electrical motor arrangement for applying in operation torque to the at least three wheels to propel the electric vehicle in a forward or a reverse direction, characterized in that:

(i) the electrical motor arrangement includes at least three electrical motors for applying in operation torque to the at least three wheels;

(ii) the at least three electrical motors are mutually independently controllable from a motor control arrangement of the electric vehicle;

(iii) at least one of the at least three electrical motors is implemented as an in-hub electrical motor; and

27. An electrical vehicle of claim 26, characterized in that each of the at least three electrical motors 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 elements includes a central hole;

- a rotor including

- one or more planar rotor elements attached to the shaft;

- magnetic bearings coupled to ends of the shaft of the rotor.

28. An electric vehicle of claim 27, characterized in that at least one of the at least three electrical motors is operable to function as a digitally- commutated electrical motor, wherein, during commutation, current pulses are applied to commutation windings of the at least one electrical motor, and a free-wheeling period is implemented between the current pulses during which the commutation windings are non-energized.

29. An electrical vehicle of claims 27 or 28, characterized in that the motor control arrangement includes a rotor excitation unit to couple electrical power from a battery arrangement of the electrical vehicle to a resonant inductive power coupling arrangement, wherefrom the electrical power is coupled wirelessly to the rotors of the at least three electrical motors for generating a rotor magnetic field that is operable to interact in operation with a commutated magnetic field of the stators of the at least three electrical motors.

30. An electrical vehicle of claims 27, 28 or 29, characterized in that the rotors of the at least three electrical motors include a rectifier arrangement for converting resonant inductively coupled power received wirelessly at the rotors into a direct current to generate the rotor magnetic field.

31. An electrical vehicle of any one of claims 27 to 30, characterized in that the rotors of the at least three electrical motors are operable to rotate at a maximum rotation rate in a range of 30000 rotations per minute to 100000 rotations per minute.

32. An electrical vehicle of any one of claims 27 to 31, characterized in that the motor control arrangement includes a switching control unit for switching commutation magnetizing currents supplied to the stators of the at least three electrical motors when in operation.

33. An electrical vehicle of any one of claims 27 to 32, characterized in that at least one of the at least three electrical motors are coupled to a planetary gearbox arrangement for coupling a torque generated at the rotors to its corresponding wheel of the electrical vehicle.

34. An electrical vehicle of claim 33, characterized in that the planetary gearbox arrangement includes a cascaded configuration of a plurality of planetary gears.

35. An electrical vehicle of any one of claims 26 to 34, characterized in that at least one of the at least three electrical motors includes a regenerative braking coil arrangement for generating electrical power from the at least one electrical motor when regenerative braking is applied in operation to recharge the battery arrangement of the electrical vehicle.

36. An electrical vehicle of any one of claims 26 to 35, characterized in that the electrical vehicle includes two front wheels provided with corresponding in-hub electrical motors, and two rear wheels provided with corresponding two rear electrical motors mounted onto the vehicle frame arrangement, such that the two rear electrical motors are implemented as sprung mass of the electrical vehicle, and coupled to their respective wheels via a flexible torque-coupling arrangement.

37. An electrical vehicle of claim 36, characterized in that the battery arrangement includes a first battery unit and a second battery unit, wherein the first battery unit is operable to provide electrical power to the two rear electrical motors of the electrical vehicle and the second battery unit is operable to provide electrical power to the two in-hub electrical motors of the electrical vehicle.

38. An electrical vehicle of any one of claims 26 to 38, wherein the electrical motor control arrangement is operable to execute at least one of:

(a) applying a forwardly-directed traction force to one or more electrical motors associated with one or more front wheels of the electrical vehicle and a backwardly-directed retarding traction force to one or more electrical motors of one or more rear wheels of the electrical vehicles to straighten-up a forward trajectory of the electrical vehicle when driving on slippery road surfaces; and

(b) applying differential torque between right-side wheels and left-side wheels of the electrical vehicle when the electrical vehicle executes turning maneuvers when in operation.

39. A method of providing motive torque in an electric vehicle including a vehicle frame arrangement, at least three wheels rotatably coupled onto the vehicle frame arrangement, and an electrical motor arrangement for applying in operation torque to the at least three wheels to propel the electric vehicle in a forward or a reverse direction, characterized in that the method includes:

(ii) arranging for the at least three electrical motors to be mutually independently controllable from a motor control arrangement of the electric vehicle;

(iii) arranging for at least one of the at least three electrical motors to be implemented as an in-hub electrical motor; and

(iv) arranging for at least one of the at least three electrical motors to be implemented as a sprung element of the vehicle frame arrangement and to be coupled via a coupling arrangement to its corresponding wheel.

40. A method of claim 39 characterized in that the method includes arranging for the at least three electrical motors to include:

- a casing;

- a rotor including

- one or more planar rotor elements attached to the shaft;

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

- magnetic bearings coupled to ends of the shaft of the rotor.

41. A method of claim 40, characterized in that the method includes arranging for at least one of the at least three electrical motors to function as a digitally-commutated electrical motor, wherein, during commutation, current pulses are applied to commutation windings of the at least one electrical motor, and a free-wheeling period is implemented between the current pulses during which the commutation windings are non-energized.

42. A method of claim 40 or 41, characterized in that the method includes arranging for the motor control arrangement to include a rotor excitation unit to couple electrical power from a battery arrangement to a resonant inductive power coupling arrangement, wherefrom the electrical power is coupled wirelessly to the rotors of the at least three electrical motors for generating a rotor magnetic field that is operable to interact in operation with a commutated magnetic field of the stators of the at least three electrical motors.

43. A method of claims 40, 41 or 42, characterized in that the method includes arranging for the motor control arrangement to include a rectifier arrangement for converting resonant inductively coupled power received wirelessly at the rotors into a direct current to generate the rotor magnetic field.

44. A method of any one of claims 40 to 43, characterized in that the method includes arranging for the rotors of the at least three electrical motors to be operable to rotate at a maximum rotation rate in a range of 30000 rotations per minute to 100000 rotations per minute.

45. A method of any one of claims 40 to 44, characterized in that the method includes arranging for the motor control arrangement to include a switching control unit for switching commutation magnetizing currents supplied to the stators of the at least three electrical motors when in operation.

46. A method of any one of claims 40 to 45, characterized in that the method includes arranging for at least one of the at least three electrical motors to be coupled to a planetary gearbox arrangement for coupling a torque generated at the rotors to its corresponding wheel of the electrical vehicle.

47. A method of claim 46, characterized in that the method includes arranging for the planetary gearbox arrangement to include a cascaded configuration of a plurality of planetary gears.

48. A method of any one of claims 39 to 47, characterized in that the method includes arranging for at least one of the at least three electrical motors to include a regenerative braking coil arrangement for generating electrical power from the at least one electrical motor when regenerative braking is applied in operation to recharge the battery arrangement of the electrical vehicle.

49. A method of any one of claims 39 to 48, characterized in that the method includes arranging for the electrical vehicle to include two front wheels provided with corresponding in-hub electrical motors, and two rear wheels provided with corresponding two rear electrical motors mounted onto the vehicle frame arrangement, such that the two rear electrical motors are implemented as sprung mass of the electrical vehicle, and coupled to their respective wheels via a flexible torque- coupling arrangement.

50. A method of claim 49, characterized in that the method includes arranging for the battery arrangement to include a first battery unit and a second battery unit, wherein the first battery unit is operable for providing electrical power to the two rear electrical motors of the electrical vehicle and the second battery unit is operable for providing electrical power to the two in-hub electrical motors of the electrical vehicle.

51. A method of any one of the claims 39 to 50, characterized in that the method includes arranging for the electrical motor control arrangement to be operable to execute at least one of: