CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a U.S. National Phase of International Patent Application Serial No. PCT/AU2018/000065 entitled “A VEHICLE CHARGING STATION,” filed on May 8, 2018. International Patent Application Serial No. PCT/AU2018/000065 claims priority to Australian Patent Application No. 2017901696 filed on May 8, 2017 and Australian Patent Application No. 2017902796 filed on Jul. 17, 2017. The entire contents of each of the above-referenced applications are hereby incorporated by reference for all purposes.

FIELD OF THE INVENTION

The present invention relates to a vehicle charging station.

The invention has been developed primarily for use with plug-in electric vehicles and will be described hereinafter with reference to that application. However, it will be appreciated that the invention is not limited to these particular fields of use and is also applicable to other vehicular uses such as plug-in hybrid electric vehicles, whether for private, commercial or other use. The invention is also applicable to non-vehicle uses such pumps, compressors, and many other applications of portable and fixed electric machines in many different industries.

BACKGROUND

Any discussion of the background art throughout the specification should in no way be considered as an admission that such art is widely known or forms part of common general knowledge in the field.

Electric vehicles have been available for many decades and make use of one or more electric machines to provide locomotive drive for the vehicle. In more recent times this form of vehicle is becoming increasingly more viable as cars, vans, busses and trucks for private and commercial use. Electric vehicles offer many advantages over vehicles with an internal combustion engine (ICE) and hybrid ICE/electric motor vehicles. However, the major relative disadvantages or drawbacks of electric vehicles, in fact or in perception, remain as: the range that is available between recharging is relatively short; and the charging time, particularly to obtain a full charge, is long relative to the refueling time for a car with an ICE.

To encourage the sale and use of electric vehicles at least one electric vehicle manufacturer, as well as other non-manufacturers, are making efforts to have purpose-built rapid charging stations constructed in a number of different locations. This however remains a very expensive infrastructure-based solution that will take considerable time to meaningfully deploy.

The requirement for purpose-built charging stations and other infrastructure to reduce the duration of the recharging time for electric vehicles arises partly from the installation within such vehicles of recharging circuitry that is only capable of accommodating relatively low power levels. One factor contributing to the lack of dedicated high power recharging circuitry in the vehicles is to reduce the cost of manufacture of the vehicles. However, other design motivations are to reduce the weight and size of the vehicles. It will be appreciated that providing high power components on-board a vehicle, and the need to keep those components within acceptable operating temperature ranges, adds cost, consumes considerable space and adds considerable weight. This last factor greatly diminishes vehicle performance and range, which perpetuates the problem that is trying to be solved. Additionally, the weight of the dedicated recharging components carried by a vehicle can be considered dead weight, as it is traditionally only used when the vehicle is stationary and not operating.

One partial solution that has been proposed to this problem is to include in an electric vehicle a power conversion device that is a drive circuit for the electric machine and a charging circuit for the on-board battery. An example of such a power conversion device is disclosed in Chinese utility patent CN 203708127, where use is made of all three of the motor windings of a switched reluctance motor for charging the battery from an AC source. This prior art arrangement is however limited in operation and application. By way of example, it is limited to: an AC input for charging; and a switched reluctance motor. Moreover, it is not able to gain the benefits of scale, in that where use is made of multiple motors there is also a need to make use of multiple versions of the conversion device.

A further solution to this problem has been proposed by the present patent applicant, and is the subject matter of international patent application PCT/AU2016/050852, the content of which is incorporated herein by way of cross-reference. The architecture disclosed in this international application has wide application to electric vehicles. However, it has also further highlighted the disadvantages mentioned above that are inherent in conventional charging station methodologies.

Although it is possible for those vehicles having the architecture referred to in the preceding paragraph to be charged at conventional vehicle charge stations, it is not always possible to gain all the benefits of the onboard regulation that is offered by the new architecture. However, to realise those gains would likely require considerable replication of infrastructure at each charging station to accommodate more vehicle types. Moreover, as charging voltages, currents and cycles change with the development and deployment of new vehicles and technologies, this infrastructure overhead will only increase, and potentially prohibitively. Moreover, such an outcome will only further any range anxiety of consumers and hinder the uptake of electric vehicles.

Accordingly, there is a need in the art for an improved vehicle and an improved vehicle charging station.

SUMMARY OF THE INVENTION

It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative.

According to a first aspect of the invention there is provided A charging station for an electric vehicle, wherein the electric vehicle has a body, a first coupler mounted to the body, and a first communications module, and wherein the charging station includes:

a second coupler for releasably complementarily coupling with the first coupler for allowing a transfer of energy from the second coupler to the first coupler at a coupler voltage and a coupler current;

a second communications module for communicating first charging data with the first communications module;

an interface for connecting with an external source of electrical energy;

a control module for providing control signals; and

a switching module that is responsive to the control signals for selectively:

connecting the second coupler and the interface for allowing the transfer of energy between the couplers; and

operating in: a first mode to allow at least one of the coupler current and the coupler voltage to be regulated; or a second mode to allow the coupler current and the coupler voltage to be unregulated.

In an embodiment the station includes a DC energy storage device and the switching module is responsive to the control signals for selectively connecting the storage device with the second coupler for allowing the transfer of energy between the couplers.

In an embodiment the switching module is responsive to the control signals for selectively disconnecting the storage device from the second coupler.

In an embodiment the switching module is responsive to the control signals for selectively connecting the storage device with the interface for allowing transfer of energy between the storage device and the external source.

In an embodiment the energy storage device has a device current and a device voltage and the switching module is responsive to the control signals for operating in a third mode for connecting the interface and the storage device such that at least one of the device current or device voltage is regulated by the interface.

In an embodiment, in a mode of operation, the switching module is responsive to the control signals for operating in a fourth mode for connecting the interface and/or the storage device with the second coupler for allowing the coupler current to be drawn, at least in part, from at least one of the interface or the energy storage device.

In an embodiment the coupler voltage is directly derived from the device voltage.

In an embodiment the first charging data is indicative of whether the station is to operate in the first mode or the second mode.

In an embodiment the interface includes a regulator for transferring energy with the external source and for providing an output current and an output voltage to transfer energy with at least one of the storage device and the second coupler, wherein at least one of the output current or the output voltage is regulated.

In an embodiment one or more of the device voltage and device current is defined, at least in part, by the respective output voltage and the output current.

In an embodiment the switching module, in a fifth mode, is responsive to the control signals for selectively transferring energy between the storage device and the second coupler, wherein at least one of the coupler voltage and coupler current and the device voltage and device current is regulated by the interface.

In an embodiment one or more of the coupler voltage and coupler current is defined, at least in part, by the respective output voltage and the output current.

In an embodiment, when transferring energy to the external source, the output voltage and the output current is defined, at least in part, respectively by at least one of: the coupler voltage and the coupler current; and the device voltage and device current.

In an embodiment the coupler current is derived from at least one of the device current or the output current.

In an embodiment the interface includes a pair of interface terminals, the second couplers include a pair of coupler terminals wherein the interface terminals are directly connected to the second coupler terminals.

According to a second aspect of the invention there is provided a vehicle including:

a body;

a first DC energy storage device mounted to the body;

a first coupler mounted to the body for coupling with a second complementary coupler of a vehicle charging station to allow energy transfer to the first coupler, wherein the vehicle charging station includes a second DC energy storage device that provides to the second coupler an unregulated DC voltage;

an electric machine mounted to the body, wherein the machine draws a drive current from the first DC energy storage device for providing locomotive energy to the vehicle;

a first communications module, wherein the vehicle charging station includes a second communications module for communicating first charging data to the first module; and

an onboard controller that is responsive to the first charging data for allowing, when the first and second couplers are coupled, a load current to be drawn from the second energy storage device, wherein the load current allows for the generation of at least one of a regulated charging current or a regulated charging voltage for the first DC energy storage device.

In an embodiment the coupling of the first and the second couplers allows energy transfer between the couplers.

In an embodiment the first coupler includes a first pair of terminals and the second coupler includes a second pair of terminals that are complementarily engagable with the first pair of terminals.

In an embodiment the first coupler and the second coupler include respective inductive transducers for allowing the energy transfer when in proximity to each other.

In an embodiment the vehicle charging station includes a local controller and the first communications module communicates second charging data to the second communications module, wherein the local controller is responsive to the second charging data for allowing or preventing the drawing of the load current.

In an embodiment the electric machine includes one or more windings and the onboard controller controls the machine such that the drive current excites at least one of the one more windings.

In an embodiment the onboard controller controls the machine such that the load current excites at least one of the one more windings.

In an embodiment the electric machine includes a plurality of electric machines.

In an embodiment the onboard controller controls all the machines.

In an embodiment each of the first and the second energy storage devices include one or more of: at least one battery; and at least one capacitive device.

In an embodiment the charging station includes an interface with an external source of electrical energy and the interface allows for charging of the second energy storage device from the external source while the load current is being drawn.

In an embodiment the onboard controller operates in a first state when the drive current from being drawn and a second state when the load current is being drawn.

In an embodiment the first state and the second state are temporally mutually exclusive.

In an embodiment the controller selectively switches between the first state and the second state to allow charging of the first energy storage device during motion of the vehicle.

In an embodiment the onboard controller is responsive to the first and second couplers being coupled for preventing the drive current from being drawn.

In an embodiment the onboard controller is responsive to the first and second couplers being coupled for allowing the load current to be drawn.

In an embodiment the first coupler is able to accept an AC voltage, a regulated DC voltage, or an unregulated DC voltage.

In an embodiment the vehicle includes a third coupler for coupling with a fourth coupler of a further energy source to allow energy to transfer to the third coupler.

In an embodiment the coupling of the third and fourth coupler allows for energy to be transferred between the couplers.

In an embodiment the further energy source is an AC source of electrical energy.

In an embodiment the vehicle includes an AC-DC converter for selectively generating, at least in part, one or more of the regulated charging current or the regulated charging voltage for the first DC energy storage device.

In an embodiment the vehicle includes a first drive circuit and a second drive circuit that operate in a first and a second state, wherein, in the first state, the first and second drive circuits draw current from the first DC energy storage device, and wherein, in the second state, the second drive circuit is electrically disconnected from the first DC energy source and the first and second drive circuits are responsive to the load current to generate the regulated charging current and/or the regulated charging voltage.

According to a third aspect of the invention there is provided a vehicle charging station for an electric vehicle, wherein the electric vehicle has a body, a first DC energy storage device mounted to the body, a first coupler mounted to the body, an electric machine mounted to the body that draws a drive current from the first DC energy storage device for providing locomotive energy to the vehicle, a first communications module and an onboard controller for controlling the drive current and providing at least one of a regulated charging current or a regulated charging voltage to the first DC energy storage device, and wherein the vehicle charging station includes:

a second coupler for being complementarily coupled with the first coupler for allowing transfer of energy to the first coupler; and

a second communications module for communicating first charging data to the first communications module; and

a second DC energy storage device that, after communication of the first charging data, provides to the second coupler an unregulated DC voltage such that, when the first and the second couplers are coupled, a load current is able to be drawn from the second DC energy storage device to thereby allow the onboard controller to generate at least one of the regulated charging current and the regulated charging voltage.

In an embodiment the second energy storage device includes one or more of: at least one battery; and at least one capacitive device.

In an embodiment the charging station includes an interface with an external source of electrical energy for allowing the second energy storage device to be charged from the external source.

In an embodiment the interface is bidirectional and allows the second energy storage device to be discharged to the external source.

In an embodiment the interface allows for charging of the second energy storage device from the external source while the load current is being drawn.

In an embodiment the external source is an electrical grid.

In an embodiment the first communications module communicates second charging data to the second communications module.

In an embodiment the vehicle charging station includes a station controller that is responsive to the second charging data for allowing one or more of: the load current to flow once the first and second couplers are electrically coupled; the availability of the second coupler to be electrically coupled to the first coupler; and defining a maximum allowable value for the load current.

In an embodiment the first and the second coupler include respective pairs of terminals.

In an embodiment the external source includes one or more intermittent power sources.

In an embodiment the interface includes a rectifier circuit.

In an embodiment the interface includes a bidirectional rectifier/inverter.

In an embodiment the interface includes a power factor correction circuit.

According to a fourth aspect of the invention there is provided a method of operating a vehicle charging station for an electric vehicle, wherein the electric vehicle has a body, a first DC energy storage device mounted to the body, a first coupler mounted to the body, an electric machine mounted to the body that draws a drive current from the first DC energy storage device for providing locomotive energy to the vehicle, a first communications module and an onboard controller for controlling the drive current and providing at least one of a regulated charging current or a regulated charging voltage to the first DC energy storage device, and wherein the method includes the steps of:

complementarily coupling the first coupler with a second coupler of the vehicle charging station for allowing energy to be transferred to the first coupler;

communicating first charging data from the station to the first communications module using a second communications module; and

a second DC energy storage device that, after communication of the first charging data, provides to the second coupler an unregulated DC voltage such that, when the first and the second couplers are coupled, a load current is drawn from the second DC energy storage device and the energy transferred to the first coupler for use by the onboard controller to generate at least one of the regulated charging current and the regulated charging voltage.

According to a fifth aspect of the invention there is provided a vehicle including:

a body;

a DC energy source mounted to the body;

a connector mounted to the body for connecting with an external energy source;

an electric machine mounted to the body for providing locomotive energy to the vehicle, wherein the or each machine has a stator, a rotor mounted to the stator for rotation, and one or more windings; and

a controller for operating in a first state and a second state wherein, in the first state, the controller allows current to be drawn from the DC energy source for energising at least one of the one or more windings such that the electric machine provides the locomotive energy and, in the second state, the controller controls the position of the rotor relative to the stator and allows at least one of the one or more windings to be energised to provide a charging current to the DC energy source.

In an embodiment the controller, in the second state, actuates a locking unit to restrain the rotor against rotation relative to the stator.

In an embodiment the locking unit includes at least one of the one or more windings.

In an embodiment the vehicle includes a further electric machine having one or more windings, wherein the locking unit includes at least one of the one or more windings of the further electric machine.

In an embodiment the locking unit mechanically locks the rotor against rotation.

In an embodiment the locking unit includes a parking pawl.

In an embodiment the locking unit includes a handbrake.

In an embodiment the vehicle includes a decoupling unit for selectively decoupling the electric machine from the locking unit.

In an embodiment the vehicle includes at least one wheel that is driven when the electric machine provides locomotive energy to the vehicle, wherein the decoupling unit selectively decouples the electric machine from the at least one wheel.

In an embodiment the decoupling unit includes a clutch.

In an embodiment the controller progresses between the first and second state to control the position of the rotor relative to the stator.

In an embodiment the electric machine includes a plurality of magnetic poles and the parking pawl is aligned with the poles.

In an embodiment the controller is responsive to movement of the vehicle for controlling the position of the rotor relative to the stator.

In an embodiment the electric machine includes a plurality of magnetic poles and the controller, in the second state, controls the position of the rotor to align with the magnetic poles.

In an embodiment the electric machine includes a plurality of magnetic poles and the controller, when transitioning from the first state to the second state, controls the position of the rotor to align with the magnetic poles.

In an embodiment the vehicle includes at least two electric machines and wherein the controller controls, during the second state, one of the at least two electric machines to substantially or wholly counteract the torque of the other of the at least two electric machines.

In an embodiment the controller controls, during the second state, the position of the rotor of one of the at least two electric machines by energising at least one of the one or more windings of the other of the at least two electric machines.

In an embodiment the electric machine has two or more sets of windings and the controller, in the second state, energises at least one of the two or more sets of the windings selectively to substantially or wholly counteract torque generated by the other of the two or more sets of windings.

In an embodiment the vehicle includes drive circuits for the respective two or more sets of windings, wherein the controller operates: the drive circuits of one of the two or more sets of windings in the first state to control the rotor position; and the other drive circuits in the second state to control the rotor position.

In an embodiment the electric machine includes a plurality of electric machines.

In an embodiment the controller, during the second state, continuously controls the position of the rotor relative to the stator.

Reference throughout this specification to “one embodiment”, “some embodiments” “an embodiment”, “an arrangement”, “one arrangement” means that a particular feature, structure or characteristic described in connection with the embodiment or arrangement is included in at least one embodiment or arrangement of the present invention. Thus, appearances of the phrases “in one embodiment”, “in some embodiments”, “in an embodiment”, “in one arrangement”, or “in and arrangement” in various places throughout this specification are not necessarily all referring to the same embodiment or arrangement, but may. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to one of ordinary skill in the art from this disclosure, in one or more embodiments or arrangements.

As used herein, and unless otherwise specified, the use of the ordinal adjectives “first”, “second”, “third”, etc., to describe a common object, merely indicate that different instances of objects in a given class of objects are being referred to, and are not intended to imply by their mere use that the objects so described must be in a given sequence, either temporally, spatially, in ranking, in importance or in any other manner.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the invention belongs. The articles “a” and “an” are used herein to refer to one or to more than one (that is, to at least one) of the grammatical object of the article unless the context requires otherwise. By way of example, “an element” normally refers to one element or more than one element. As used herein, the term “exemplary” is used in the sense of providing examples, as opposed to indicating quality. That is, an “exemplary embodiment” is an embodiment provided as an example, as opposed to necessarily being an embodiment of exemplary quality.

The term “electric machine” is used in a broad sense to include electric motors, generators and other electromechanical devices that convert electrical energy into mechanical energy, or vice versa, or both. For convenience, and unless is otherwise clear from the context, the terms “electric motor” or “motor” are used as an equivalent for, and interchangeably with, the terms “electric machine” or “machine”.

Reference in this specification to the term “vehicle” includes a reference to both land-based vehicles and other vehicles such as aircraft and watercraft. Typical examples of land-based vehicles include plug-in electric vehicles and plug-in hybrid electric vehicles. These electric vehicles and hybrid electric vehicles are not limited to cars, and include also trucks, buses, forklifts, scooters, electric bicycles, motorcycles and other personal transportation devices, buggies (such as golf carts and the like), mining equipment, agricultural equipment, recreational vehicles, and others.

