The present invention relates to a charging system for providing electricity to electricity-powered vehicles and a method for installing such a system. The charging system is particularly adapted for constituting part of a multi-functional charging system for integration into an existing urban infrastructure.
In recent years there has been a drive towards cleaner vehicles; in particular governments have encouraged the use of electric cars. This is increasingly being achieved through legislations. The tendency is to penalise owners and drivers of larger petrol and diesel vehicles and encourage the use of clean vehicles—such as electric or hybrid vehicles.
The rapid increase in electricity-powered vehicles create however challenges, especially in urban locations such as inner cities. For examples, setting up new charging stations is an expensive exercise, requiring earthwork for cabling and purchase of extensive new infrastructure. The need of blocking at least parts of the locations traffic network may be very disruptive to city traffic, thereby triggering further costs.
Systems and methods that may deliver electricity to charge batteries of electricity-powered vehicles which includes a large number of charging stations making use of already existing municipal facilities such as street lights and parking meters have therefore acquired a high degree of attention in the last years, in particular from governmental authorities.
Configurations, maintenance, and operation on charging stations must be performed with a minimum amount of manual configuration work in order for non-expert service technicians to carry out the work. The charging stations are preferably equipped with plug system, thereby avoiding the need for authorized electricians.
Installing charging stations in existing municipal facilities are known. As a typical example,
Electricity powered vehicles may thus charge their batteries by electrically connecting the charging cable to power outlets 21 which again is electrically connected to a control system 20. The charging station 1a may route the available power to the control system or to other charging stations 1a by us of dedicated connection box 50.
Examples of such prior art systems may be found in patent publications WO 2012/122072 A2 and WO 2013/034872 A2.
However, such prior art solutions necessitate arrangements of the charging systems outside the existing municipal facility, making these solutions less compact. In addition, the charging stations must accept incoming power levels equal to the power levels available in existing municipal power grids. Alternatively, the power level or the power grid must be at acceptable charging powers for electricity-powered vehicles, normally 230 V or 110 V.
An object of the invention to provide scalable, compact and highly secure charging system for electricity-powered vehicles (EV) which may be easily integrated into a fixture of an existing or new urban infrastructure such as lamp posts, parking meters and the like.
Another object of the invention is to provide the above charging system that allows use of existing or new urban infrastructures having limited internal space for installation of new electrical components.
Another object of the invention is to provide the above charging system that allows lower power losses compared to traditional charging systems.
Another object of the invention is to provide the above charging system that allows less dependency on available power grids' electrical characteristics.
Another object of the invention is to provide the above charging system that allows safe charging of EVs from unearthed electrical networks such as the IT system.
Another object of the invention is to provide the above charging system that allows distribution of available power from the power grid in the most efficient way.
Various other objects and advantages of the invention will become apparent to those skilled in the art by perusing the accompanying specification, drawings and claims.
The present invention is set forth and characterized in the main claims, while the dependent claims describe other characteristics of the invention.
In particular, the invention concerns a charging system suitable for supplying charging power to an electricity-powered vehicle. The charging system comprises at least one fixture of type EVSE fixture, wherein each EVSE fixture comprises at least one power inlet for receiving electrical energy, an EVSE control device and an EV plug. The EVSE control device is configured to charge, via the EV plug, a rechargeable battery powering the electricity-powered vehicle. The energy transfer from the EV plug to the battery may take place via a charging cable. The charging system further comprises a primary power source arranged outside the at least one EVSE fixture for supplying electric energy (PS) to the at least one power inlet of the at least one EVSE fixture. The charging system is characterized in that the at least one EVSE fixture further comprises at least an EVSE solid state transformer having a primary side being electrically connectable to the primary power source for receiving electric energy at a voltage level VPS and a secondary side providing electric energy at a voltage level VEVSE, the secondary side being electrically connectable to the EVSE control device, either directly or indirectly. For example, the secondary side may be permanently connected to the EVSE control device or connected manually or remotely by a connection box containing one or more relays.
The above mentioned primary power source may be a power grid delivered by local or national authorities and may be configured to deliver power to the power inlet either directly by arranging dedicated cables to each fixture, or indirectly via another fixture. The latter may be accomplished by use of connection boxes with suitable relays.
In an advantageous embodiment both the EVSE control device and the EVSE solid state transformer system are arranged fully within the at least one fixture.
In another advantageous embodiment the charging system includes a plurality of spaced apart fixtures, each having at least one power inlet for receiving electrical energy. At least one of the plurality of fixtures is in this particular embodiment of type EVSE fixture.
In yet another advantageous embodiment the charging system is a multipurpose charging system further comprising a second electric load arranged at least partly within the at least one fixture. This second electric load may be electrically connectable to the EVSE control device system.
In yet another advantageous embodiment each of the at least one fixture contains a solid state transformer system comprising the EVSE solid state transformer and a second solid state transformer arranged within at least one of the at least one fixture. The second solid state transformer comprises a primary side being electrically connectable to the primary power source for receiving electric energy at the voltage level VPS and a secondary side providing electric energy at a voltage level VEL. The secondary side is in this embodiment electrically connectable, directly or indirectly, to the second electric load. The second solid state transformer may be arranged in parallel to the EVSE solid state transformer within the solid state transformer system.
In yet another advantageous embodiment the primary side of the EVSE solid state transformer, or both the EVSE solid state transformer(s) and the second solid state transformer(s), is/are electrically isolated from the secondary side of its/their respective solid state transformer(s).
In yet another advantageous embodiment the voltage level VPS is higher than the voltage level VEVSE.
In yet another advantageous embodiment the voltage level VPS is equal to, or approximately equal to, the voltage level VEVSE.
In yet another advantageous embodiment each EVSE fixture of the at least one fixture comprises monitoring means configured to monitor physical parameters descriptive of the performance of the EVSE solid state transformer and transmission means configured to allow access and transmission of the physical parameters to computer networks, for example via cloud based storage systems. The primary side of the EVSE solid state transformer may in this embodiment be electrically isolated from the secondary side of the EVSE solid state transformer, and the monitoring means and the transmission means may be configured to detect and to transmit, respectively, any insulation fault occurring within the EVSE solid state transformer. The transmissions may be to power grids and/or any consumers of electric energy.
In yet another advantageous embodiment the EVSE solid state transformer comprises a protection device enabling measurement and/or detection of any anomalous electrical behaviour such as transient overvoltage, undervoltage, power consumption, earth fault, excess temperature, electric noise, or a combination thereof. The measurement/detection is followed by transmission of the parameter(s) to a computer network, for example a cloud based data storage. A detection of an earth fault may be obtained by use of one or more earth fault protection relays.
In yet another advantageous embodiment the charging system further comprises a communication module configured to receive and transmit data from/to the fixtures and/or a computer network, for example via a cloud service. The communication module may further be configured to receive and transmit data from/to the primary power source.
In yet another advantageous embodiment each EVSE fixture comprises an EVSE data communication device enabling reception and transmission of data between the EVSE control device and the EVSE solid state transformer.
In yet another advantageous embodiment the EV plug comprises an EV power outlet and an EV communication module, wherein the EV communication module is configured to transmit data to a computer network, for example to/via a cloud service.
In yet another advantageous embodiment the charging system includes a plurality of spaced apart fixtures including at least one being of type EVSE fixture and that each fixture have at least one power inlet for receiving electrical energy. Furthermore, each fixture comprises in this embodiment a connection box comprising a plurality of relays.
The connection box is configured to electrically connect and/or disconnect the at least one power inlet with the EVSE solid state transformer and electrically connect and/or disconnect the at least one power inlet with the at least one power inlet of another of the fixture within the charging system.
In yet another advantageous embodiment each EVSE fixture comprises a plurality of EVSE plugs configured to connect and disconnect at least the EVSE control device and the EVSE solid state transformer to/from the respective EVSE fixtures. The EVSE plugs comprises a control system plug electrically connected to the EVSE control device and a power inlet plug electrically connected to the primary side of the EVSE solid state transformer.
All the above mentioned data communication may be obtained by use of standards such as PLC, Ethernet, RS-485, CAN-bus or any other hardwire system and/or WIFI, BLE, LoRa, GPRS, 3G, 4G, 5G or any other wireless system.
The invention also concerns a method using an existing, hollow fixture connected to a primary power source via at least one power inlet in order to provide charge for a rechargeable battery powering an electricity-powered vehicle, wherein the fixture comprises an electrical load. The method comprises the steps of
In an advantageous method the EVSE plugs further comprises an intermediate EV plug, and the method further comprises the step of installing the EV plug into one of the at least one opening and electrically connecting the intermediate EV plug into a corresponding inner plug of the EV plug.
The one or more fixtures of the charging system may constitute part of an urban infrastructure, i.e. structures, systems, and facilities serving the economy of a business, industry, country, city, town, or area, including the services and facilities necessary for its economy to function. For example, the fixtures may be part of a road network system, i.e. arranged in, or adjacent to, a road, where at least one of the second electric loads comprises a light source for providing street light to roads and/or parking lots.
In the following description, numerous specific details are introduced to provide a thorough understanding of embodiments of the claimed charging system and its method. One skilled in the relevant art, however, will recognize that these embodiments can be practiced without one or more of the specific details, or with other components, systems, etc. In other instances, well-known structures or operations are not shown, or are not described in detail, to avoid obscuring aspects of the disclosed embodiments.
As described above
A SST is herein defined as an electric energy converting device that operates at much higher frequencies (several kHz) than conventional transformers (50/60 Hz). The SST must be equipped with at least one high-frequency transformer combined with at least one electronically controlled switch (transistor or similar). The SST will also need a control system to control the switching sequence and frequency.
The very same control system may also be used to monitor voltages, currents and internal temperatures for self-protection and reporting purposes.
An example of a solid state transformer may be found disclosed in the publication 978-1-4244-2893-9/09 2009 IEEE p. 3039-3044, which is hereby incorporated as reference. In this connection particular reference is made to
In addition to the criteria given by the above definition, most SSTs should preferably contain one or more of
SSTs are described in literature under a large variety of names. The following names give a non-exhaustive list of transformers that all fall under the above definition of SST:
After having been converted PS to the desired power level(s) by the SSTs 10′,10″ a control device system 20 further routes, and possible modulates, the power prior to be sent to the electric load(s) 30 and/or the EV outlets 21. The control device system 20 may comprise two different control devices 20′,20″ for handling converted power from the SSTs 10′,10″. The control device(s) 20′,20″ may comprise relays, frequency converters, AC/DC converters, or any other components enabling routing and/or modulation of voltage power and data communication signals.
As better illustrated in
In the embodiments shown in
Data communication may also take place, hardwired and/or wireless, between the SST system 10 and the control device system 20. Further, transmitters/receivers may be arranged within the SST system 10 in addition to, or in instead of, within the control device system 20. And as illustrated in
The voltage is routed and optionally modulated by the control device system 20 for further supply to the electric lamp and the EV power outlet 21. If the supply is performed via PLCs or other data communication means, any information concerning the performance of the control system 20 and/or the SST system 10 may be communicated as well to the EV communication module 21b. The stipled vertical line in
Further details of the electrical installations within an EVSE fixture 1a are shown in
Note however that components considered necessary for implementation of the invention are defined in the main claims.
The transformation of a high voltage power PS supplied by a power grid 80 down to a lower voltage power PEV/PEL suitable for charging the EV and/or any other electric loads 30 connected within the same fixture 1a has the advantage of lowering the energy loss within the charging system. The reason for this can be summarized as follows: Any power grid 80 may deliver a maximum power PSmax. Further, power lost in the wires can be calculated as Ploss=Rwires*I2grid, with Rwires being the resistance of the wires and Igrid being the current passing through them. Power at the load, Pload, is calculated as Pload=Vgrid*Igrid, where Vgrid is the voltage provided by the power grid. If the supplied voltage from the power grid, Vgrid, is doubled (V′grid=2*Vgrid), the same power at the load Pload is obtained by use of half of the original current ½*Igrid, hence inducing power loss Ploss of only a quarter of the power (P′loss=¼*Ploss).
Another important advantage of allowing higher voltage power into each fixture is the availability. A user or operator of the charging system may choose to upgrade or downgrade the available voltage power within one, some or all of the fixtures 1a at any time of the day.
In the embodiment of
The charging system shown in
As best described with reference to
The hollow fixture 1 shown in the embodiment shown in
The scalable, multipurpose charging system may advantageously have an intelligent phase distribution system as shown in
In the preceding description, various aspects of the charging system according to the invention have been described with reference to the illustrative embodiment. For purposes of explanation, specific numbers, systems and configurations were set forth in order to provide a thorough understanding of the system and its workings. However, this description is not intended to be construed in a limiting sense. Various modifications and variations of the illustrative embodiments, as well as other embodiments of the system, which are apparent to persons skilled in the art to which the disclosed subject matter pertains, are deemed to lie within the scope of the present invention.
Filing Document | Filing Date | Country | Kind |
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PCT/EP2016/076116 | 10/28/2016 | WO | 00 |