The present invention pertains to systems and methods for charging a plurality of electric vehicles from a same power source. More particularly, the present invention pertains to systems and methods for sequentially charging electric vehicles during successive charging cycles. The present invention is particularly, but not exclusively, useful as a system or method for providing an n number of charging stalls to sequentially charge an N number of vehicles during a charging cycle, when N is less than or equal to n.
Along with an increasing interest in the use of electricity for generating vehicular motive power, a consequent interest concerns how to provide the electrical power for this purpose. As is well known and appreciated, the task of electrically charging a vehicle takes time (e.g. several hours). Further, the actual time that is needed to efficiently charge a vehicle is dependent on several factors, such as power level and charging point availability. Moreover, the industry has now progressed to the point where operational and structural standards have been established for manufacturing components for use at a charging station. With all this in mind, the issue becomes how best to achieve maximum charging efficiency, within existing industry requirements, for as many electric vehicles as possible.
Range anxiety and charger availability are some of the biggest concerns for electric vehicle (EV) drivers. More abundant and available charging infrastructure is the best way to combat these concerns, but installing new complete stations can be expensive and difficult due to electrical grid or power supply limitations, installation costs, and permitting. Additionally, each EV charging station (EVCS) can only supply a finite amount of power through one, or at most, two standard outlets with current designs. Coupled with extended charge times, this means EVCS installations can quickly become unavailable in frequented charging areas.
SAE J1772 is an international standard that defines the physical design, communications protocol, and power requirements of the charging interface and controllers within an EV and an EVCS. The standard connector is called a coupler on the EVCS side and an inlet on the EV side. There are 5 electrical pins within each coupler: 2 power, 1 ground, and 2 control pins called a pilot and proximity. The pilot pin is the primary control connection that passes the required communication signal to enable, initialize, and monitor charging between an EV and an EVCS. The proximity pin is part of a separate control circuit within a coupler and an EV that informs the EV when a coupler is being connected or removed. Power requirements fall within two categories under the standard. Level 1 charging uses a 120 volt (V) alternating current (AC) circuit while Level 2 charging requires a 240V AC circuit. Both power levels can be supplied over the same coupler design and all existing Level 1 and Level 2 stations must follow this standard.
SAE J1772 also defines a standard combination coupler with extra pins to pass direct current (DC) at increased Level 1 and Level 2 rates. The DC charging sequence is controlled and monitored by a similar proximity and pilot methodology as the AC standard. CHAdeMO is a third standard for DC charging at high rates. The coupler and communications protocol are different from the SAE J1772 standard, but the overall process is similar.
With the above in mind, it is an object of the present invention to provide a system and method for increasing the available charging infrastructure for electric vehicles by adapting existing charging stations with a multi-coupler expansion adapter that will simultaneously accommodate a plurality of electric vehicles. Another object of the present invention is to provide a multi-coupler adapter for use with a single power source which sequentially charges a plurality of electric vehicles. Yet another object of the present invention is to provide a multi-coupler expansion adapter that is simple to use, is relatively easy to manufacture, and is comparatively cost effective.
In accordance with the present invention, a multi-coupler expansion adapter is provided which will increase the available charging infrastructure for electric vehicles using the same charging station. Specifically, this is done by adapting existing charging stations so they can simultaneously accommodate a plurality of electric vehicles. In their combination, components of the present invention incorporate the multi-coupler expansion adapter to interconnect a single power source with a variable plurality of different electric vehicles (e.g. 6 or 8 vehicles).
For the methodology of the present invention, a time duration, td, is established during which each electric vehicle is individually charged. In this scheme, td remains constant and it is the same for each vehicle. Charging the plurality of vehicles that is connected into the system is then conducted continuously in a sequence of time durations, td. The sum total, Σtd, results in an uninterrupted charging time cycle, Tcycle. According to the present invention, as the number of vehicles in the plurality is increased, or decreased, Tcycle will respectively increase or decrease by the increment/decrement td.
Components for the multi-coupler adapter of the present invention include, in combination, a controller, a sensor and a timer. In this combination, the controller is used for individually connecting a power source to each electric vehicle in the plurality of the electric vehicles. More specifically, as intended for the present invention, the controller gives the adapter a capability for individually connecting with an n number of different electric vehicles. For this capability, the sensor is used for identifying the N number of vehicles that are actually connected with the controller, at any one time. Thus, although N will fluctuate depending on the number of vehicles being charged, N will always be less than n+1. The timer that is included in the multi-coupler adapter is used for actuating the controller to sequence individual connections of time duration td, between the power source and the N number of electric vehicles.
With the above in mind, several important aspects of the invention deserve consideration. For one, Tcycle=Ntd=Σtd, and td will preferably be equal to approximately ten minutes. Further, as indicated above, N will fluctuate. Therefore, N will need to be reset with a decrement 1 whenever an electric vehicle has been charged and removed from the system. N will also need to reset with an increment 1 whenever an electric vehicle is initially connected into the system.
In accordance with regulatory requirements, the multi-coupler adapter will include a first power pin for providing power from the power source to charge the electric vehicle at a level 1 rate. The multi-coupler adapter will also include a second power pin for providing power from the power source to charge the electric vehicle at a level 2 rate. As envisioned for the present invention, charging at either of these rates will be accomplished in response to an operation of the controller. Further, the power level that is provided by the power source for charging an electric vehicle may be 120 volts alternating current (120V AC), 240 volts alternating current (240V AC) or a direct current voltage.
With the above in mind, a method for sequentially charging a plurality of electric vehicles in accordance with the present invention requires first setting up the system. In essence, this involves providing a power source which has been adapted to service an n number of charging stalls. Further, each of the charging stalls is configured to establish an appropriate individual power connection between the power source and the electric vehicle that is using the stall. In particular, this adaptation is accomplished by the multi-coupler adapter of the present invention.
Once the power source has been prepared for operation, the methodology of the present invention requires identifying the N number of vehicles that are actually connected with the controller of the multi-coupler adapter. Recall, N will be less than n+1. With N established, a sequence of connections is actuated between the power source and the N number of electric vehicles. In detail, this sequence extends during the time of an uninterrupted sequence cycle, Tcycle, and it is continuously repeated. Importantly, during each Tcycle, each electric vehicle is connected with the power source for a same time duration td.
As a sequence of cycles is repeated, it is anticipated that N will fluctuate. If so, N will be reset with a decrement 1 when an electric vehicle has been charged and removed from the system, and it will be reset with an increment 1 whenever an electric vehicle is initially connected into the system. Moreover, empty stalls in the sequence cycle will simply be bypassed.
The novel features of this invention, as well as the invention itself, both as to its structure and its operation, will be best understood from the accompanying drawings, taken in conjunction with the accompanying description, in which similar reference characters refer to similar parts, and in which:
Referring initially to
In general, the system 10 will be capable of charging an n number of vehicles 18 during a defined time cycle, Tcycle. Typically, n will be six or eight. For disclosure purposes, however, the system 10 that is shown in
A schematic of the operational components for a multi-coupler adapter 12 of the present invention is shown in
In detail,
Still referring to
Structurally, the controller 28 of the system 10 is used for individually connecting the power source 14 with each electric vehicle 18 in the plurality of possible electric vehicles 18a-f. As intended for the present invention, the adapter 12 has the capability for individually connecting with all of the n number of different electric vehicles 18 in the n different stalls (i.e. a-f), at the same time. As envisioned for the present invention, however, there will be times when some of the stalls a-f will be vacant. For this eventuality, the sensor 24 is provided to identify the N number of vehicles 18 that are actually connected with the controller 28 at any particular time. Thus, at any given time, N may be less than n, or it may be equal to N (i.e. 0<N≦n). Stated differently, however, N is always an integer less than n+1.
Within the adapter 12, the timer 26 is used to actuate the controller 28, and to thereby sequence connections between the power source 14 and the N number of electric vehicles 18. For the present invention, this sequencing is accomplished during the time of an uninterrupted sequence cycle, Tcycle. During this sequence cycle, Tcycle, each electric vehicle 18 is connected with the power source 14 for a same time duration td.
Referring now to
With reference to the example presented above for vehicles 18a, 18d, and 18f, N=3. Further,
The essential tasks to be performed during an operation of the system 10 are presented in their interactive sequencing in the logic flow chart 48 shown in
When collectively considering the inquiry blocks 54 and 56 together with the action blocks 58 and 60 in flow chart 48, it will be further appreciated that the system 10 has the capability of adjusting its configuration, depending on changes in N. Specifically, as N changes, it can be appropriately incremented whenever an additional electric vehicle 18 is connected into the system 10, or it can be decremented whenever an electric vehicle 18 is disconnected and removed from the system 10. In any event, the inquiry block 62 requires at least one electric vehicle 18 be connected into the system 10 before proceeding with a charging operation.
Whenever N≧1, and with any changes in N being accounted for, the action block 64 requires that Tcycle be calculated. As previously disclosed elsewhere herein, this calculation is accomplished by setting Tcycle=Ntd. This being done, action block 66 indicates that Tcycle is to be executed. At this point it is noteworthy to recall that Tcycle operates continuously. In particular, Tcycle is uninterrupted and bypasses empty stalls as long as N≧1. Moreover, it is continuously repeated until N=0.
During an operation of the system 10, inquiry block 68, action block 70 and inquiry block 72, collectively indicate that as Tcycle is being executed the electric vehicle 18 in a particular active stall (e.g. electric vehicle 18f considered above) will be charged during a time duration td. Thereafter, action block 74 indicates that Tcycle is sequentially advanced to the next stall. On the other hand, whenever a particular stall a-f is empty, inquiry block 68 and action block 74, together, indicate that the empty stall will be bypassed.
While the particular System and Method for Charging a Plurality of Electric Vehicles as herein shown and disclosed in detail is fully capable of obtaining the objects and providing the advantages herein before stated, it is to be understood that it is merely illustrative of the presently preferred embodiments of the invention and that no limitations are intended to the details of construction or design herein shown other than as described in the appended claims.