WO2010132443A1

WO2010132443A1 - Systems and methods for providing electric grid services and charge stations for electric vehicles

Info

Publication number: WO2010132443A1
Application number: PCT/US2010/034380
Authority: WO
Inventors: Michael Edward Kasaba
Original assignee: Advanced Power Technologies, Inc.
Priority date: 2009-05-11
Filing date: 2010-05-11
Publication date: 2010-11-18

Abstract

Disclosed are systems and methods for providing electric grid services and charge stations for electric vehicles. In certain embodiments, a charging station includes an energy storage component such as a battery bank that received and stores at least a portion of electrical energy from a grid. Such stored electrical energy can be drawn from for charging of electric vehicles, thereby providing an energy buffering capability. In certain embodiments, such stored electrical energy can be transferred to the grid when needed, such as when the grid experiences an unexpected fluctuation in energy demand, thereby stabilizing the performance of the grid. Various components and functionalities of a charging station that can facilitate charging of electric vehicles on one end and stabilizing the grid on the other end are disclosed.

Description

SYSTEMS AND METHODS FOR PROVIDING ELECTRIC GRID SERVICES AND CHARGE STATIONS FOR ELECTRIC VEHICLES

BACKGROUND

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of priority under 35 U. S. C. § 119(e) to U.S. Provisional Application Number 61/216,027, filed on May 11 , 2009, entitled "SYSTEM FOR PROVIDING ELECTRIC GRID SERVICES AND CHARGE PORTS FOR ELECTRIC VEHICLES," the entirety of which is incorporated herein by reference.

BACKGROUND Field

[0002] The present disclosure generally relates to the field of electrical energy technology, and more particularly, to systems and methods for providing electric grid services and charge stations for electric vehicles.

Description of the Related Art

[0003] Electric vehicles can be configured in different types and sizes; and whatever form they may be in, they need to be recharged. Such recharging typically occurs at a charging site, where electrical energy from a utility service is formatted appropriately for charging of batteries.

[0004] In general, electrical energy for consumption, including consumption by recharging of the electric vehicles, is typically generated by a relatively small number of power generating stations. Such generation of electricity can be achieved by a number of ways. Such generated electricity is typically distributed to consumers via a network of electrical connections commonly referred to as a "grid." Grids can have different sizes and complexities, depending on factors such as geography and demand level. [0005] Electric grid operators typically operate the grid such that the amount of electrical energy produced and distributed generally meets the demand placed by consumption. Such matching of demand with supply can be achieved based on parameters such as environmental condition, time of day, and historical pattern.

[0006] When the demand exceeds the supply, energy supply can be increases by, for example, increasing the output of power generators. Such a configuration usually means that power generators need to operate with some reserve of power not used on a continuous basis. Such a setting for generating electrical energy may not be efficient.

[0007] Further, although such increasing of energy output may compensate for relatively slow increase in demand, there may be situations where relatively fast fluctuations in demand may not be addressed properly by the power generators. Such uncompensated fluctuations in electrical power can have undesirable effects in at least some of the devices and systems that consume electrical energy from the grid.

SUMMARY

[0008] In certain embodiments, the present disclosure relates to an electric vehicle charging station having a vehicle connectivity component capable of providing charging electrical energy to at least one electric vehicle. The charging station further includes an energy storage component configured to allow storage and retrieval of energy. The energy storage component is connected to the vehicle connectivity component such that at least a portion of the charging electrical energy is provided by the energy stored in the energy storage component. The charging station further includes a grid connectivity component configured to receive input electrical energy from a grid, with the grid connectivity component connected to the energy storage component such that at least a portion of the input electrical energy is provided to the energy storage component for storage. The grid connectivity component further configured to transfer at least some of the stored energy in the energy storage component to the grid as electrical energy. [0009] In certain embodiments, the energy storage component includes an electrical energy storage device capable of being charged by the input electrical energy from the grid, and discharged as the electrical energy transferred to the grid. In certain embodiments, the electrical energy storage device includes a bank of rechargeable batteries. In certain embodiments, the rechargeable batteries include lithium iron phosphate cells. In certain embodiments, the charging station further includes a battery management system for managing the bank of rechargeable batteries.

[0010] In certain embodiments, the energy storage component is further configured to allow storage of electrical energy from an auxiliary energy source. In certain embodiments, the auxiliary energy source includes at least one of a wind generator or a solar panel.

[0011] In certain embodiments, the grid connectivity component includes one or more devices configured to convert the input electrical energy from the grid into an energy form suitable for the energy storage component, and to convert an energy form suitable for retrieval from the energy storage component into a form suitable for the electrical energy transferred to the grid. In certain embodiments, each of the one or more devices is a bi-directional electrical device capable of converting the forms of electrical energy along both directions between the grid and the energy storage component. In certain embodiments, the one or more devices include an inverter configured to convert electrical energy between alternating current and direct current. In certain embodiments, the one or more devices include a transformer configured to transform electrical energy between two voltage states associated with the grid and the energy storage component.

[0012] In certain embodiments, the grid connectivity component includes an electrical filtering device configured to substantially filter out undesirable signal components in the electrical energy transferred to the grid from the energy storage component.

[0013] In certain embodiments, the charging station further includes a control component configured to control operation of one or more of the vehicle connectivity component, energy storage component, and grid connectivity component. In certain embodiments, the control component is configured to control the transfer of electrical energy from the energy storage component to the grid. In certain embodiments, the control component is configured such that the transfer of electrical energy from the energy storage component to the grid occurs when an electrical energy demand on the grid is greater than its supply by a selected amount. In certain embodiments, the control component includes a local controller located at the charging station in communication with a remote controller located at a control center for the grid.

[0014] In certain embodiments, the charging station further includes an ancillary system component configured to provide at least one of environmental control, communication, or auxiliary energy input functionalities for the charging station.

[0015] In certain embodiments, the present disclosure relates to a vehicle charging network having a plurality of the charging station summarized above.

[0016] In certain embodiments, the present disclosure relates to a method for operating an electrical grid. The method includes monitoring supply and demand of electrical energy associated with the electrical grid. The method further includes detecting a condition where the demand exceeds the supply by an amount greater than a threshold value. The method further includes sending a control signal to a plurality of electric vehicle charging stations. Each charging station has stored electrical energy that can be transferred to the grid. The charging station is configured to transfer at least a portion of the stored electrical energy to the grid in response to receipt of the control signal such that transfers of the stored electrical energy from the plurality of charging stations reduces the difference between the demand and the supply.

[0017] In certain embodiments, the condition includes a decrease in a frequency associated with an alternating current form of the electrical energy associated with the grid.

[0018] Neither this summary nor the following detailed description purports to define or limit the scope of protection. The scope of protection is defined by the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] These and other features will now be described with reference to the drawings summarized below. These drawings and the associated description are provided to illustrate specific embodiments, and not to limit the scope of protection.

[0020] Figure 1 schematically shows an electrical interconnect network, commonly referred to as a "grid," that distributes electrical energy from one or more power suppliers to one or more electricity consumers.

[0021] Figure 2 shows that a grid can be of different size and complexity.

[0022] Figure 3 shows an example of how a supply of electrical energy in the grid generally matches a demand; however, there are situations where the supply and demand can deviate from each other significantly.

[0023] Figure 4 schematically depicts an electric vehicle charging station having an energy storage component that can provide an energy buffer as the charging station receives energy from the grid and charges a number of electric vehicles.

[0024] Figure 5 schematically shows that a number of charging stations can be serviced by a given grid, where each charging station is similar to that of Figure 4.

[0025] Figure 6 shows that the energy buffer in the charging station can reduce the deviation of the supply and demand, especially if there are a number of such charging stations.

[0026] Figure 7 schematically depicts an electric vehicle charging station having an energy storage component such that at least some of the stored energy can be transferred to the grid when needed.

[0027] Figure 8 schematically shows that a number of charging stations can be connected to a given grid, where each charging station is similar to that of Figure 7.

[0028] Figure 9 shows that the capability to transfer energy from the charging station to the grid can further aid in stable operation of the grid, including an ability to address relatively quick fluctuations in demand, especially if there are a number of such charging stations.

[0029] Figure 10 schematically shows that in certain embodiments, an interface system for a charging station can include various components such as a grid connectivity component, an energy storage component, a vehicle connectivity component, and an ancillary systems component.

[0030] Figure 11 schematically shows that in certain embodiments, a control component can be configured to control various functions of the various components shown in Figure 10.

[0031] Figure 12 schematically shows a number of different components that can be part of the ancillary systems component of Figure 10.

[0032] Figures 13A - 13C schematically show non-limiting examples of how the control component of Figure 11 can be implemented.

[0033] Figures 14A and 14B show that the energy storage component of Figure 10 can include an electrical energy storage device such as a battery bank, and/or a non-electrical energy storage device.

[0034] Figure 15 shows that in certain embodiments, a process can be implemented to control transfer of electrical energy from the charging station to the grid.

[0035] Figure 16 shows that in certain embodiments, a process can be implemented such that the transfer of energy from the charging station to the grid is initiated when the demand exceeds the supply by a threshold amount.

[0036] Figure 17 shows a process that can be implemented as a more specific example of the process of Figure 16.

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS [0037] The present disclosure generally relates to systems and methods for interfacing one or more electrical vehicle charging stations with an electrical network. Generally, as shown in Figure 1 , such charging stations can be part of power consumers 104 who consume electrical power supplied by one or more power suppliers 102. As is generally known, distribution and delivery of such electrical power to the consumers 104 are achieved by an electrical interconnect network 100. Such a network is commonly referred to as an "electrical grid," or simply as a "grid."

[0038] For the purpose of description herein, a grid can have different sizes and/or different complexities. For example, Figure 2 shows that a continental grid 110 can service a continent. Within a given continent, there may be one or more national grids 112 and/or one or more regional grids 114 that may or may not be part of the continental grid 110. There also may be one or more local grids 116 that may or may not be part of the regional, national, or continental grid.

[0039] By way of an example, North America includes a number of regional grids; and some of such grids can service parts of United States and Canada. In many situations, size and extent of grids can be dictated by a number of factors such as geography and power consumption demand. In certain situations, grids themselves may be interconnected so as to allow transfer of power as needed to provide stability to electrical infrastructures associated with various regions or nations.

[0040] Figure 3 shows an example of how a given grid can be operated to provide such stability of electrical infrastructures. An average power demand (depicted by a dashed-line curve 120) typically changes during a typical day. For example, demand for power can increase during business hours during a weekday and peak at some time during such hours. On the other hand, power consumption is likely to be significantly less at night when most businesses are closed and people are sleeping. A weekend day will likely have an average demand curve that is different than that of a business day profile.

[0041] Whatever a particular average demand profile may look like, a grid operator operates its grid so as to attempt to meet the demand. Adjusting the output(s) of power generator(s) and/or adjusting distribution of such output power are non-limiting examples of measures that can be taken to balance the demand load with supply. Thus, in Figure 3, an average supply (depicted by a solid-line curve 122) is shown to generally track the average demand curve. [0042] However, there may be situations where there may be significant differences between the demand and supply. Such differences are depicted at three example times indicated as 124a, 124b and 124c. Such differences can arise due to, for example, unexpected demands imposed on the grid. For example, at time 124a, average demand is shown to increase significantly from the average supply. The grid's supply is shown to increase its supply to compensate for the increased demand; and such increase in supply is shown to overcompensate at time 124b. Similarly, an attempt to compensate for the overcompensation at time 124b can result in too much reduction in supply at time 124c.

[0043] Figure 4 shows that in certain embodiments, a charging station 134 can be configured to include an energy storage component 136. The charging station 134 can also be configured to receive electrical energy (depicted as arrow 132) from a grid 130. The grid 130 can be any one or some combination of the different grids described herein in reference to Figures 1 and 2.

[0044] In the example configuration shown in Figure 4, at least some of the electrical energy received from the grid 130 can be stored in the energy storage 136. Further, at least some of output energy from the charging station 134 for charging one or more electrical vehicles 142a, 142b can be drawn from the energy storage 136, as depicted by arrows 140a and 140b.

[0045] One can see that use of such an energy storage in a charging station can provide an energy buffer between the grid and the electrical vehicles being charged. Accordingly, fluctuations in energy demand (e.g., resulting from fluctuations in the number of electrical vehicles being serviced) associated with the charging station can be accommodated by the buffer, thereby resulting in the grid being less susceptible to having the supply deviate from the actual demand.

[0046] Unless an energy storage capacity of a given charging station is relatively large so as to form a significant portion of a given grid's energy budget, it is unlikely that the charging station alone will significantly impact a relatively large electrical grid. In certain situations, such a large energy storage capability may not be desirable due to various reasons, including cost and complexities (e.g., maintenance and safety). [0047] However, as shown in Figure 5, a number (N) of charging stations 134 receiving energy (arrows 132) from the same grid 130 can constitute a significant portion of the grid's energy budget. By distributing the energy buffer capacity to N such charging stations, each energy storage can have a lower energy storage capacity and associated lower cost and complexities; and yet, as a group, the N charging stations can provide a significant impact in the grid's operation.

[0048] Accordingly, as shown in Figure 6, an average power demand (depicted by a dashed-line curve 150) associated with the grid 130 of Figure 5 will likely be better accommodated by an average supply (depicted by a solid-line curve 152). More particularly, example differences between the demand and supply (indicated as 154a, 154b, 154c) will likely be less than those (124a, 124b, 124c) associated with the example described in reference to Figure 3.

[0049] In certain embodiments, a charging station can be configured to provide at least some of the electric energy stored therein to the grid. Figure 7 shows an example configuration where a charging station 160 can be configured to include an energy storage component 162. The charging station 160 can also be configured to receive electrical energy from the grid 130 and also to supply electrical energy to the grid 130 as needed. Such a capability of receiving and supplying electric energy from and to the grid is depicted as a double-ended arrow 164. The grid 130 can be any one or some combination of the different grids described herein in reference to Figures 1 and 2.

[0050] In the example configuration shown in Figure 7, at least some of the electrical energy received from the grid 130 can be stored in the energy storage 136. In certain embodiments, and as described herein, the energy storage 136 can also be provided with input energy from other sources not directly associated with the grid 130. Such energy sources can include, but are not limited to, wind-driven generator and solar panels.

[0051] Similar to the vehicle-charging example of Figure 4, at least some of output energy from the charging station 160 for charging one or more electrical vehicles 172a, 172b can be drawn from the energy storage 162, as depicted by arrows 170a and 170b. Additionally, aside from the energy buffer functionality provided by the energy storage 162 (similar to that of Figure 4), the charging station's (160) capability of providing electrical energy to the grid 130 allows the grid 130 to be operated in a more stable manner and to respond to load fluctuations in a more effective manner.

[0052] Similar to the example configurations described in reference to Figures 4 and 5, it is unlikely that a single charging station (such as the charging station 160 of Figure 7) will significantly impact a relatively large electrical grid. However, as shown in Figure 8, a number (N) of charging stations 160 receiving energy from and supplying energy to (arrows 164) from the same grid 130 can constitute a significant portion of the grid's energy budget. Aside from advantages provided by distribution of the energy buffer capacity to N such charging stations, the distributed form of relatively small energy sources in the form of the energy storages 162 of the charging stations 160 allows the grid to respond more quickly and effectively to load fluctuations.

[0053] Such load fluctuations are shown by way of example in Figure 9, where an average power demand is depicted by a dashed-line curve 170, and an instantaneous power demand is depicted by a dotted-line curve 180. For the purpose of description herein, the term "instantaneous" does not necessarily mean precisely real-time; but rather can include time scales that are approximately real time in the context of monitoring an electrical load placed on the grid. In certain situations, "instantaneous" demand can also include relative short-duration spikes (e.g., spike 182, where demand significantly exceeds the supply) or dips (e.g., dip 182, where supply significantly exceeds the demand) that are unpredictable and/or sufficiently short-lived such that a traditional grid control cannot respond to in an effective manner.

[0054] With respect to the dip-in-demand situation (e.g., 184 in Figure 9), such a situation can result in a power spike being delivered to various electricity consumers. Many electrical interface systems (e.g., between end-user devices and the grid) and end-user devices can be configured to protect against such surges that can be damaging to electrical equipments. Such protection can include devices such as power regulators, fuses, and the like. [0055] Electrical power that is underpowered (e.g., due to spike in demand 182 in Figure 9) can also be damaging to certain electrical equipments. While some of such equipments themselves may be equipped to prevent damage due to such a power dip (demand spike), applicant does not believe that there is an interface system (e.g., between end-user devices and the grid) that can address such a problem.

[0056] In certain situations, a traditional grid control system detects an increase in demand by detecting a change in the operating frequency of alternating current (AC) being delivered via the grid. For example, lowering of the AC frequency can indicate that the supply is being strained. Once such a condition is detected, a traditional method of compensating the condition is to increase the power output of the power generator(s) associated with the grid.

[0057] Such a traditional power compensation method can have a number of drawbacks. For example, the power generators generally need to operate at less than full capacity to be able to provide a compensation reserve during peak output periods. Such an operating condition may not provide an ideal efficiency in power generation. In another example, due to the centralized nature of the traditional power compensation method, power dips and compensation measures are typically propagated throughout the entire grid, and accordingly may suffer from effects associated with large scale operation (e.g., slow response time).

[0058] Figure 10 schematically depicts an interface system 200 configured to provide an interface between one or more charging stations with an electrical grid 130. In certain embodiments, the interface system 200 can be configured to provide one or more features associated with the energy buffering capability and/or the capability to transfer electrical energy from the one or more charging stations to the grid.

[0059] In certain embodiments, various components of the interface system 200 can be grouped functionally. For example, the system 200 can include an energy storage component 210 that is interconnected with the grid 130 via a grid connectivity component 230 so as to be able to receive and send electrical energy from and to the grid 130 (depicted as a double-ended arrow 214). Various components and functionalities associated with the grid connectivity component 230 are described herein in greater detail.

[0060] The energy storage component 210 is shown to be also connectable with one or more electrical vehicles (not shown) via a vehicle connectivity component 220. In certain embodiments, electrical energy provided by the energy storage component 210 to the vehicle connectivity component 220 can be a one-way transfer as depicted by an arrow 216.

[0061] In certain embodiments, the energy storage component 210 includes an electrical energy storage device such as a battery bank 212. In certain embodiments, the battery bank 212 can include one or more rechargeable battery units, including but not limited to lithium ion battery cells and lithium iron phosphate cells. In certain embodiments, lithium iron phosphate cells can be interconnected and arranged into a module, and a number of such modules can be interconnected and arranged into an array having a voltage in a range of about 750 VDC to 1050 VDC, a power rating of about 100 KW, and an energy rating of about 25 KW-hour. The battery bank 212 can have a number of such arrays, with the number depending on a design power target for the energy storage component 210. In certain embodiments, such a design power target can be based on factors such as an expected number of vehicles to be charged and an estimate of electrical energy reserve desired for possibly sending to the grid. For example, five arrays can yield a total power rating of about 500 KW and a total energy rating of about 125 KW-hour.

[0062] In certain embodiments, charging and discharging characteristics of the battery bank 212 can be configured so as to limit vehicle charging processes and discharging of energy to the grid. For example, charging of a given vehicle can be limited to about 15 minutes; and sending of electricity to the grid 130 from the battery bank 212 can be limited to a few minutes. In certain situations, such few minutes of energy transfer from the battery bank 212 to the grid 130 can be followed by an increased output from one or more generators associated with the grid 130. Such measures can ensure that the battery bank has a reserve of energy substantially continuously and reduce the probability of the battery bank 212 being undesirably drained. [0063] In certain embodiments, the foregoing assembly of battery cells at the example module level can be managed by a level-one battery management system. The example array of such modules can be managed by a level-two battery management system. The example battery bank (212) of such arrays can be managed by a level-three battery management system. In certain embodiments, the foregoing three levels of battery management systems can be those known in the art.

[0064] In certain embodiments, the level-three battery management system can be in communication with a controller. In Figure 10, the level-three battery management system is depicted as component 242, and the controller is depicted as component 240. In certain embodiments, the battery management system architecture can be configured so as to allow hot swapping of battery modules for efficient maintenance without having to take down the battery bank 212.

[0065] In certain embodiments, the electrical energy stored in the battery bank 212 can be energy received from the grid 130. In certain embodiments, the battery bank 212 can optionally be charged from a source other than the grid 130. For example, electrical generation devices such as wind turbines and solar panels can provide auxiliary energy input (indicated as an arrow 218) into the battery bank 212. Although energy input rate from such sources may not be high as that from the grid 130, such sources can be steady so as to allow build-up of reserve energy. Further, a large number of battery banks associated with a large number of charging stations can facilitate easier integration of alternative sources of energy into readily accessible and useful electrical energy by providing a widely distributed storage capability.

[0066] In the example shown in Figure 10, the vehicle connectivity component 220 includes a charge regulator 222 that is provided with electrical energy from the battery bank 212 (arrow 216) for regulated charging of one or more electrical vehicles (indicated by arrows 224). Receipt of electrical energy, conversion into an appropriate form for charging, and distribution of such charging current can be achieved in a number of ways. For example, for direct current (DC) charging, the charge regulator 222 can include a DC to DC converter that is configured to convert the DC power (e.g., 1 ,000 VDC) of the battery bank 212 into a DC power range (e.g., about 300 VDC to 650 VDC) appropriate for charging electrical vehicles.

[0067] In certain embodiments, such a converted DC voltage can be provided with current to achieve a desired power output. For example, suppose that a target power output of about 100 KW is desired per vehicle. Such a power output can provide about 25 KW-hour of electrical energy (roughly the amount of energy to allow about 100 miles of travel in a small to mid-sized electric vehicle) in about 15 minutes.

[0068] In the example shown in Figure 10, the vehicle connectivity component 220 is depicted as receiving electrical energy from the battery bank 212. In certain embodiments, at least some of the electrical energy delivered to the vehicle connectivity component 220 can be bypass the battery bank 212. For example, a portion of the electrical energy from the grid can be conditioned appropriately and be fed to the vehicle connectivity component 220 without having to go through the battery bank. Such a configuration can be based on a number of factors, including efficiency of battery charging/discharging processes, desired energy buffering effect of the battery bank, and expected vehicle charging throughput. For example, if charging and discharging of the battery bank is not efficient, or if the vehicle charging throughput is too high for the battery bank's power rating, it may be desirable to at least supplement the battery bank-provided energy with the bypassed energy. In another example, if the buffering effect is a high priority consideration, then it may be desirable to have substantially all of the energy to the vehicle connectivity component 220 be provided by the battery bank 212.

[0069] In the example shown in Figure 10, the vehicle connectivity component 220 is depicted as also including a vehicle control interface component 226 and a customer interface component 228. In certain embodiments, the vehicle control interface component 226 can include an appropriate module and a connector (e.g., SAE standard connector) for communicating (e.g., via CAN communication protocol) with a vehicle's battery management system. Once connected, the vehicle's battery management system temporarily take control of the charging process to provide desired voltage and current settings for the vehicle and to avoid damage and safety hazard.

[0070] In certain embodiments, the customer interface 228 can include an interface device (e.g., display and input devices) and a payment processing device (e.g., for payments using credit or debit cards). Interconnection and operation of such an interface device and payment processing device in conjunction with tracking of energy being provided during charging can be achieved in a number of known ways.

[0071] In the example shown in Figure 10, the grid connectivity component 230 includes a battery management system 242 that can be under the control of a controller 240. The battery management system 242 can be configured to provide one or more levels of battery management as described herein in reference to the battery bank 212 of Figure 10.

[0072] In certain embodiments, the grid connectivity component 230 can include a number of components that are configured to facilitate electrical current between the grid 130 (e.g., AC) and the energy storage component 210 (e.g., DC). Such transfers of electrical energy are depicted by the double-ended arrow 214. In certain embodiments, such components can provide functionalities such as a converter 232, a filter 234, and a transformer 236. By way of a non-limiting example, suppose that the grid operates at about 13.8 KVAC, and the battery bank 212 operates at about 1 ,000 VDC. The foregoing three example components can be configured to facilitate transfer and conditioning of electrical energy between these two formats.

[0073] In certain embodiments, the converter 232 can be an inverter (e.g., an active bridge inverter) capable of converting the electrical currents between the energy storage component 210 and an intermediate form that can be transformed to the grid's format. For example, the 1 ,000 VDC current from the battery bank 212 can be converted to an alternating current operating at about 480 VAC. The inverter 232 can be rated to handle the power associated with the electrical energy transfer (e.g., about 1 KW to 125 KW). In certain embodiments, the inverter 232 can be a bi-directional device that allows transfer of electricity in both directions. In certain embodiments, the inverter 232 can include separate uni-directional devices, each configured to allow a uni-directional transfer. A number of converting techniques known in the art can also be utilized.

[0074] In certain embodiments, the filter 234 can be configured to reduce or remove unwanted noise or signals from the currents being transferred. For example, the filter 234 can include a filtering capability that substantially eliminates a switching frequency signal (e.g., at about 2,000 Hz) that can be introduced during the battery bank-to-grid transfer (e.g., DC to AC) conversion. Such a filter can yield a substantially clean AC waveform (e.g., approximately 60 Hz) that is sent to the grid 130. In certain embodiments, such a filter can be an LC-based filter. A number of filtering techniques known in the art can also be utilized.

[0075] In certain embodiments, the transformer 236 can be configured to transform electrical current between the grid 130 and the above-described intermediate format. For example, the 480 VAC (output from the inverter 232) can be transformed to the grid format of 13.8 KVAC. A number of known electrical transformation techniques can be utilized.

[0076] In the example shown in Figure 10, the grid connectivity component 230 includes an interface component 244. In certain embodiments, the interface component 244 can include a control system such as a supervisory control and data acquisition (SCADA) system having subsystem functionalities associated with programmable logic controller (PLC) and remote control unit (RTU). Such an interface component 244 can allow interfacing of one or more functionalities associated with the interface system 200 with a grid control system (not shown) via, for example, an energy management system 246.

[0077] In the example shown in Figure 10, various components of the vehicle connectivity component 230 are depicted as being controlled by a controller 240. In certain embodiments, such a controller can be configured to control, for example, energy transfer between the grid 130 and the energy storage component 210, interfacing with the grid control system (not shown), and the management of the battery bank 212. [0078] In the example shown in Figure 10, the interface system 200 can include an ancillary system component 250. In certain embodiments, the ancillary system component 250 can include one or more components configured to support various functionalities being provided by the interface system 200. In certain embodiments, some of the components associated with the ancillary system component 250 can be configured to comply with various regulations such as safety regulation.

[0079] For example, and as shown in Figure 12, the ancillary system component 250 can include features such as an environment control component 252, a communication component 260, and an auxiliary energy input component 262. The environment control component 252 can include structures and/or features such as an enclosure 252, lighting 254, fire suppression 256, and air conditioning 258.

[0080] In certain embodiments, the enclosure 252 can be configured to include mounting systems for battery racks, inverter cabinets, grid connectors, communication systems, lighting, fire suppression, etc. In certain embodiments, the enclosure 252 can be based on an existing structure such as a 20-ft shipping container.

[0081] In certain embodiments, the lighting 254 can be configured to provide light for personnel while performing maintenance and other routine activities in the enclosure 252.

[0082] In certain embodiments, the fire suppression 256 can include, among others, a capability to suppress possible fires associated the battery bank. For example, a lithium fire (if lithium based batteries are being used) usually cannot be suppressed with traditional carbon dioxide or water based systems. Accordingly, a special chemical compound that buries the lithium fire can be utilized to contain the fire and associated damage.

[0083] In certain embodiments, the air conditioning 258 can be configured to provide a desired range of air temperature for various components inside the enclosure 252. For example, an ambient air temperature of about 70 to 80 degrees Fahrenheit can be provided. To accomplish such a temperature range for a 500 KW charging station, about two 4-ton AC units can be provided.

[0084] In certain embodiments, the communication component 260 can be configured to provide the various interface functionalities described in reference to Figure 10. Such communication functionalities can be facilitated by an internet connection via, for example, DSL, satellite, cable, and the like.

[0085] In certain embodiments, the auxiliary energy input component 262 can be configured to allow inputting of electrical energy into the battery bank. For example, solar and/or wind generators can be connected to the battery system; and the electrical current thus provided can be converted appropriately for charging of the battery system. In certain embodiments, such an auxiliary input can provide about 10 to 15 KW of power to the battery system. In the wind generator example, the generated electrical current can be converted to DC appropriately. In the solar panel example, the DC output of the solar panel can be transformed into another DC appropriately.

[0086] Figure 11 shows that in certain embodiments, the controller 240 (Figure 10) can be a part of a control component 270 associated with the interface system 200. The control component 270 can be configured to control one or more functionalities associated with the controller 240 and/or the grid connectivity component, vehicle connectivity component (depicted as 272), energy storage component (depicted as 274), energy management system interface (depicted as 276), and administrative interface (depicted as 278).

[0087] In certain embodiments, the controller 240 can be configured to control various features of the grid connectivity component 230 as described herein in reference to Figure 10. Such control can facilitate the transfer of electrical energy between the grid and the energy storage component 210.

[0088] In certain embodiments, the vehicle connectivity control component 272 can be configured to control various features of the vehicle connectivity component 220 as described herein in reference to Figure 10. Such control can facilitate servicing of electrical vehicles from the energy storage component 210. [0089] In certain embodiments, the energy storage control component 274 can be configured to control manage the battery bank 212. Such control can include coordination of operations of the grid connectivity component 230 and the vehicle connectivity component 220 based on one or more of the battery bank's operating parameters such as state of charge, thermal readings, module status, and other battery condition variables.

[0090] In certain embodiments, the energy management system interface control component 276 can be configured to control various features of the energy management system component 246 (Figure 10) and the interface component 244. Such control can facilitate, for example, communication between the grid connectivity controller 240 and the grid operator (e.g., such as an Independent System Operator (ISO)). In certain embodiments, such communication with the ISO can be via the ISO's interface module (e.g., remote interface gateway (RIG)). In certain embodiments, control of the grid connectivity component 230 can be directed by the ISO via the foregoing communication.

[0091] In certain embodiments, the administrative interface control component 278 can be configured to allow an administrator to, for example, check status of all systems and diagnose issues. In certain embodiments, the administrative interface control component 278 can also be configured to allow override operation of one or more components of the interface system 200 (Figure 10). In certain embodiments, such administrative control can be achieved via a network such as internet so as to allow, for example, remote observation, routine operational verifications, and maintenance scheduling.

[0092] In certain embodiments, the control component 270 described herein can be configured to receive an input that in indicative of a condition (e.g., a drop in the grid's AC frequency) where input of electrical energy from one or more charging stations is desirable. Generation of such an input can be achieved in a number of known ways by the grid operator, by detection at one or more consumer locations (e.g., at one or more charging stations), or some combination thereof. Upon receipt of such an input, the control component 270 can issue one or more signals that result in transfer of electrical energy into the grid. Parameters such as the amount of energy, specific sources (which charging station(s)) of such energy and other such parameters can be determined by the control component 270 based on, for example, number of available charge stations, charge state of the stations, etc.

[0093] In certain embodiments, some or all of the control functionalities described herein, including those associated with the control component 270, can be implemented in a number of configurations. Figures 13A - 13C show non- limiting examples of such configurations.

[0094] Figure 13A shows that in certain embodiments, the control component 270 associated with the interface system 200 can be part of a charging station 160.

[0095] Figure 13B shows that in certain embodiments, the control component 270 can control functions of a charging station 160 from a remote location. Such a remote location can include, for example, another charging station, a grid control center, or a dedicated control center that controls one or more charging stations.

[0096] Figure 13C shows that in certain embodiments, the control component 270 does not need to be located at a same location. For example, a portion of the control component 270 may be located or be implemented at a charging station 160, while another portion of the control component 270 may be located or be implemented at a control location associated with a grid 130.

[0097] Other control configurations are also possible.

[0098] In the description herein, the energy storage component (e.g., 210 in Figure 10) is described in the context of electrical energy storage devices such as batteries. It will be understood that other forms of energy storage can also be implemented.

[0099] For example, Figure 14A schematically depicts a battery-based energy storage component 162 having a battery bank 212. As described in greater detail in reference to Figure 10, electrical energy can be transferred (arrow 164) between the energy storage component 162 and a grid (not shown). A charging station having such an energy storage component 162 can service a number of electric vehicles 172 by providing (arrow 170) at least a portion of charging electrical energy to the vehicles 172 via a vehicle connectivity component 220.

[0100] Figure 14B shows that in certain embodiments, a charging station 160 can be configured to receive energy from the grid (not shown) and service a number of electrical vehicles 172 via a vehicle connectivity component 220. At least a portion of such charging electricity can be provided from stored in an energy storage component 162. In the example shown, the energy storage component 162 can include a non-electrical energy storage device 280, and a converter 282 configured to convert (arrow 284) electrical energy into the form of energy being stored in the storage device 280. For example, suppose that the energy storage device 280 includes a flywheel that stores mechanical energy. Conversion between the electrical and mechanical forms of energy can be achieved by, for example, an electrical motor and a generator. In some situations such conversion devices can be combined as a single motor/generator device.

[0101] In Figure 14B, transfer of electrical energy (arrow 164) between the energy storage component 162 and the grid is depicted as being facilitated by the converter 282. Similarly, the energy storage component 162 is depicted as providing electrical energy to the vehicle connectivity component 220 via the converter 282.

[0102] Some non-limiting examples of processes that can be implemented in the control component (e.g., 270 in Figures 11 and 13) are shown in Figures 15 - 17. Figure 15 shows that in certain embodiments, a process 300 can be implemented to facilitate transfer of electrical energy between a grid and one or more charging stations. In block 302, one or more parameters representative of a grid operating condition can be monitored. For example, the operating frequency of the grid's AC can be monitored. In block 304, energy transfer between the grid and one or more charging stations can be adjusted based on the one or more parameters monitored. For example, if the operating frequency is lowered below some threshold, energy can be transferred into the grid so as to stabilize the operating frequency into an acceptable range. [0103] Figure 16 shows that in certain embodiments, a process 310 can be implemented as an example where electrical energy is transferred into the grid. In block 312, energy supply and demand associated with a grid can be monitored. In block 314, the process 310 can generate a signal that induces flow of electricity into the grid if the demand exceeds the supply by a threshold amount. Such a flow of electricity into the grid can be from one or more charging stations as described herein.

[0104] Figure 17 shows that in certain embodiments, a process 320 can be implemented as a more specific example of the process 310 of Figure 16. In block 322, a frequency of AC power being provided from a grid to one or more destinations can be monitored. Based on the value of the frequency, the process 320 in a decision block 324 can determine whether to draw energy from a reserve (e.g., battery banks of charging stations). In certain embodiments, a decision to draw from the reserve can be based on the monitored frequency. For example, if the frequency is lower than some threshold value, the process 320 can determine that energy should be drawn from the reserve. If the answer in the decision block 324 is "No," the process 320 can continue to monitor the AC frequency (in block 322). If the answer is "Yes," the process 320 (in block 326) can generate a control signal to induce transfer of stored electrical energy from one or more charging stations into the grid. The process 320 can continue to monitor the AC frequency.

[0105] In one or more example embodiments, the functions, methods, algorithms, techniques, and components described herein may be implemented in hardware, software, firmware (e.g., including code segments), or any combination thereof. If implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Tables, data structures, formulas, and so forth may be stored on a computer-readable medium. Computer-readable media include both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage medium may be any available medium that can be accessed by a general purpose or special purpose computer. By way of example, and not limitation, such computer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code means in the form of instructions or data structures and that can be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor. Also, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. Disk and disc, as used herein, includes compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

[0106] For a hardware implementation, one or more processing units at a transmitter and/or a receiver may be implemented within one or more computing devices including, but not limited to, application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, micro-controllers, microprocessors, electronic devices, other electronic units designed to perform the functions described herein, or a combination thereof.

[0107] For a software implementation, the techniques described herein may be implemented with code segments (e.g., modules) that perform the functions described herein. The software codes may be stored in memory units and executed by processors. The memory unit may be implemented within the processor or external to the processor, in which case it can be communicatively coupled to the processor via various means as is known in the art. A code segment may represent a procedure, a function, a subprogram, a program, a routine, a subroutine, a module, a software package, a class, or any combination of instructions, data structures, or program statements. A code segment may be coupled to another code segment or a hardware circuit by passing and/or receiving information, data, arguments, parameters, or memory contents. Information, arguments, parameters, data, etc. may be passed, forwarded, or transmitted via any suitable means including memory sharing, message passing, token passing, network transmission, etc.

[0108] Various combinations of the above-described features and components are possible, and all such combinations are contemplated by this disclosure.

[0109] Conditional language, such as, among other terms, "can," "could," "might," or "may," and "preferably," unless specifically stated otherwise, or otherwise understood within the context used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements and/or steps.

[0110] Many variations and modifications can be made to the above- described embodiments, the elements of which are to be understood as being among other acceptable examples. Thus, the foregoing description is not intended to limit the scope of protection.

Claims

WHAT IS CLAIMED IS:

1. An electric vehicle charging station, comprising: a vehicle connectivity component capable of providing charging electrical energy to at least one electric vehicle; an energy storage component configured to allow storage and retrieval of energy, the energy storage component connected to the vehicle connectivity component such that at least a portion of the charging electrical energy is provided by the energy stored in the energy storage component; and a grid connectivity component configured to receive input electrical energy from a grid, the grid connectivity component connected to the energy storage component such that at least a portion of the input electrical energy is provided to the energy storage component for storage, the grid connectivity component further configured to transfer at least some of the stored energy in the energy storage component to the grid as electrical energy.

2. The charging station of Claim 1 , wherein the energy storage component comprises an electrical energy storage device capable of being charged by the input electrical energy from the grid, and discharged as the electrical energy transferred to the grid.

3. The charging station of Claim 2, wherein the electrical energy storage device comprises a bank of rechargeable batteries.

4. The charging station of Claim 3, wherein the rechargeable batteries comprise lithium iron phosphate cells.

5. The charging station of Claim 3, further comprising a battery management system for managing the bank of rechargeable batteries.

6. The charging station of Claim 1 , wherein the energy storage component is further configured to allow storage of electrical energy from an auxiliary energy source.

7. The charging station of Claim 6, wherein the auxiliary energy source comprises at least one of a wind generator or a solar panel.

8. The charging station of Claim 1 , wherein the grid connectivity component includes one or more devices configured to convert the input electrical energy from the grid into an energy form suitable for the energy storage component, and to convert an energy form suitable for retrieval from the energy storage component into a form suitable for the electrical energy transferred to the grid.

9. The charging station of Claim 8, wherein each of the one or more devices is a bi-directional electrical device capable of converting the forms of electrical energy along both directions between the grid and the energy storage component.

10. The charging station of Claim 9, wherein the one or more devices comprise an inverter configured to convert electrical energy between alternating current and direct current.

11. The charging station of Claim 9, wherein the one or more devices comprise a transformer configured to transform electrical energy between two voltage states associated with the grid and the energy storage component.

12. The charging station of Claim 1 , wherein the grid connectivity component includes an electrical filtering device configured to substantially filter out undesirable signal components in the electrical energy transferred to the grid from the energy storage component.

13. The charging station of Claim 1 , further comprising a control component configured to control operation of one or more of the vehicle connectivity component, energy storage component, and grid connectivity component.

14. The charging station of Claim 13, wherein the control component is configured to control the transfer of electrical energy from the energy storage component to the grid.

15. The charging station of Claim 14, wherein the control component is configured such that the transfer of electrical energy from the energy storage component to the grid occurs when an electrical energy demand on the grid is greater than its supply by a selected amount.

16. The charging station of Claim 15, wherein the control component comprises a local controller located at the charging station in communication with a remote controller located at a control center for the grid.

17. The charging station of Claim 1 , further comprising an ancillary system component configured to provide at least one of environmental control, communication, or auxiliary energy input functionalities for the charging station.

18. A vehicle charging network comprising a plurality of the charging station of Claim 1.

19. A method for operating an electrical grid, the method comprising: monitoring supply and demand of electrical energy associated with the electrical grid; detecting a condition where the demand exceeds the supply by an amount greater than a threshold value; sending a control signal to a plurality of electric vehicle charging stations, each charging station having stored electrical energy that can be transferred to the grid, the charging station configured to transfer at least a portion of the stored electrical energy to the grid in response to receipt of the control signal such that transfers of the stored electrical energy from the plurality of charging stations reduces the difference between the demand and the supply.

20. The method of Claim 19, wherein the condition comprises a decrease in a frequency associated with an alternating current form of the electrical energy associated with the grid.