Patent Publication Number: US-2023145630-A1

Title: Aggregating capacity for depot charging

Description:
RELATED APPLICATION 
     This application is a continuation of U.S. patent application Ser. No. 17/177,498, entitled “AGGREGATING CAPACITY FOR DEPOT CHARGING,” filed on 17 Feb. 2021, which is hereby incorporated by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure generally relates to systems and methods used to convert and combine multiple power systems to provide a unified output and specifically relates to systems and methods for aggregating multiple different kinds of service capacity to support high-powered electric vehicle charging. 
     BACKGROUND 
     Electric power utility infrastructure is a serious impediment to scaled adoption of electric vehicles (EVs), particularly in a work setting where fleets of EVs need to be powered. Operators of buses, trucks, and delivery vans who are contemplating rollouts beyond pilot scale are often told by utilities that an infrastructure upgrade is required to support the charging of those vehicles, often at great expense to the customer and utility and with vague and uncertain project work timelines. Utilities usually have limited capability to adapt due to overburdened engineering departments whose primary objective is the safety and reliability of the grid as a whole rather than processing and implementing upgrades for particular customers. Accordingly, this added complexity, cost, and delays are significant roadblocks to widespread electrification of vehicles, and especially fleet vehicles which, as a fleet, require high capacity and reliability for their charging power in order to operate efficiently. For this and other reasons, there is a constant need for improvements in the field of EV charging and the provision of power to EV fleets. 
     SUMMARY 
     One aspect of the present disclosure relates to an electric vehicle charging system comprising a first utility grid connection having a first alternating current (AC) signal having a first signal type, a second utility grid connection having a second AC signal having a second signal type, an electric vehicle charging device, and an electrical bus system in electrical communication with the first and second utility grid connections and with the electric vehicle charging device. The electrical bus system can be configured to convert the first and second AC signals to a direct current (DC) signal and to convert the DC signal to an output signal for the electric vehicle charging device. 
     In some embodiments, the charging system also comprises a first electrical service panel electrically connected to the first utility grid connection, a first rectifier electrically connected to the first electrical service panel and to the electrical bus system, a second electrical service panel electrically connected to the second utility grid connection, a second rectifier electrically connected to the second electrical service panel and to the electrical bus system, and an inverter electrically connected between the electrical bus system and the electric vehicle charging device. 
     In some embodiments, the charging system comprises an energy storage device electrically connected to the electrical bus system and configured to provide energy to, or store energy from, the electrical bus system. A controller can be included that is configured to determine available power from the first utility grid connection and from the second utility grid connection, determine demand at the electric vehicle charging device, and control the electrical bus system to draw from the available power to supply the demand at the electric vehicle charging device. In some configurations, determining available power can comprise comparing an upper limit of a capacity of the first utility grid connection to present usage of the capacity. Drawing from the available power can comprise prioritizing power drawn from the first utility grid connection over power drawn from the second utility grid connection. The prioritization can be based on a tariff or time-of-use price of electricity. 
     In some embodiments, the charging system can comprise an energy generation or energy storage system electrically connected to the electrical bus system, and the electrical bus system can be configured to provide energy from the energy generator or energy storage system to the electric vehicle charging device. The energy generation or energy storage system can comprise an energy storage device electrically connected between the first utility grid connection and the electrical bus system. 
     Another aspect of the present disclosure relates to a method of managing electricity usage to charge electric vehicles, wherein the method comprises detecting a demand for an electric vehicle charging device connected to a utility customer site, determining a first power margin of a first power source connected to the utility customer site, determining a second power margin for a second power source connected to the utility customer site, with the first and second power sources having different power supply characteristics, drawing power from the first power source at a first power level within the first power margin and from the second power source at a second power level within the second power margin, and providing the drawn power to the electric vehicle charging device. 
     The first power margin can be based on an electrical service capacity of the first power source. The first power margin can also be based on time of use of the first power source or based on a previous peak consumption threshold for the first power source. In some embodiments, drawing power from the first power source and from the second power source comprises supplying power to an electrical bus, and wherein providing the drawn power to the electric vehicle charging device comprises supplying power from the electrical bus to the electric vehicle charging device. The method can further comprise providing supplemental power to the electric vehicle charging device from an energy storage device. 
     Yet another aspect of the disclosure relates to an electric vehicle charging system, comprising a first utility grid connection of a utility customer and at a site of the utility customer, a first service panel connected to the first utility grid connection, a second utility grid connection of the utility customer at the site, a second service panel connected to the second utility grid connection, an electric vehicle charging device of the utility customer at the site, a bus connecting the first and second service panels to the electric vehicle charging device, and a controller configured to manage power provided to the electric vehicle charging device via the bus. 
     In this system, the first utility grid connection and the second utility grid connection can provide different voltage access to a utility grid. The first utility grid connection and the second utility grid connection can also provide different phase-level access to a utility grid. The first service panel can comprise a first trip rating and the second service panel comprises a second trip rating, wherein the controller is configured to prevent power drawn from the first and second service panels from exceeding the respective first and second trip ratings. In some embodiments, the system further comprises an energy storage system connected to the bus, wherein the controller is configured to store excess energy from the first and second service panels using the energy storage system or to provide supplemental energy from the energy storage system to the electric vehicle charging device. 
     The above summary of the present invention is not intended to describe each embodiment or every implementation of the present invention. The Figures and the detailed description that follow more particularly exemplify one or more preferred embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings and figures illustrate a number of exemplary embodiments and are part of the specification. Together with the present description, these drawings demonstrate and explain various principles of this disclosure. A further understanding of the nature and advantages of the present invention may be realized by reference to the following drawings. In the appended figures, similar components or features may have the same reference label. 
         FIG.  1 A  is a block diagram of an electric vehicle charging system. 
         FIG.  1 B  is a block diagram of another electric vehicle charging system. 
         FIG.  2    is a block diagram of a bus system of the embodiments of  FIGS.  1  and  2   . 
         FIG.  3    is a block diagram of a controller system. 
         FIG.  4    is a process flow diagram of processes for controlling a bus system and various electronic components of an electric vehicle charging system. 
         FIG.  5    is a block diagram of a computer system. 
     
    
    
     While the embodiments described herein are susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and will be described in detail herein. However, the exemplary embodiments described herein are not intended to be limited to the particular forms disclosed. Rather, the instant disclosure covers all modifications, equivalents, and alternatives falling within the scope of the appended claims. 
     DETAILED DESCRIPTION 
     Embodiments of the present disclosure can help address challenges faced by utilities and utility customers when installing and using electric vehicle charging stations by providing systems and methods that permit high power and high reliability charging stations to be operated at existing customer sites without needing utility service upgrades or significant changes to existing utility service at those sites. 
     Some embodiments include aggregating unused capacity from multiple end-user utility service meters into a larger single block of available capacity that is provided to EV service equipment (EVSE) such as EV chargers. The aggregated available capacity or available power can be containerized and can be used with energy storage systems to improve output consistency and leveling. Thus, utility customers or other site operators having multiple electrical panels that, individually, would not effectively provide sufficient capacity to support EV charging (or fleet EV charging) can collect and use their otherwise unused capacity for those panels to provide power to a bus system with sufficient capacity for those purposes. Embodiments of the present disclosure can improve the rate of adoption of EV fleets at scale while minimizing utility service upgrades, can monetize spare utility capacity for underutilized service and assets, can enable grid services (e.g., demand response) and centralized, aggregated controls for grid operators for fleet EV charging, and can keep these systems secured and isolated from tampering by using a centralized controller. 
     In an example embodiment, an electric vehicle charging system is provided that includes a first utility grid connection having a first alternating current (AC) signal type (or a high voltage direct current (HVDC) signal type), a second utility grid connection having a second AC signal type (or another HVDC signal type), an electric vehicle charging device, and an electrical transfer bus system in electrical communication with the first and second utility grid connections and with the electric vehicle charging device. The electrical transfer bus system can be configured to convert the first and second AC signals (or HVDC signals) to a direct current (DC) signal and to convert the DC signal to an output signal for the electric vehicle charging device. Thus, the charging system can adapt and combine the capacity of two different utility grid connections (i.e., the first and second utility grid connections) using an electrical transfer bus system that converts the signals from their AC (or DC) sources to a DC signal that is usable as an output to an electric vehicle charging device. The combined power can be greater than would otherwise be possible using the first or second utility grid connections on their own, thereby unlocking the potential of those grid connections without having to modify the connections themselves. Instead, an electrical transfer bus system can be installed and connected to those grid connections, and a controller can manage the amount of power drawn from each connection to provide an amassed, collected, unified amount of power. 
     In some embodiments, the systems and methods described herein can adapt and combine the output of multiple different types of power sources to connect to the bus system. For instance, one or more of a residential-grade utility grid connection, a commercial-grade utility grid connection, an energy storage system (ESS), a fuel-based generator (e.g., diesel generator), a renewable generator (e.g., a solar panel or geothermal/wind turbine), similar devices, and combinations thereof can be connected to a single bus system for aggregation and output unification. Multiple power sources can be managed and owned by a single utility customer, or some/all can come from multiple different utility customers. In some embodiments, the connection between these power sources can be one-directional, such as in the case of a utility grid connection being connected to the bus system via a rectifier, and in some cases, the connections can be bi-directional, such as a connection between an ESS and the bus system, wherein energy can either be drawn from the ESS to the bus or energy can be directed from the bus to the ESS and stored thereon. 
     In an example embodiment, output of the aggregation system can provide a minimum of 100 kilowatts of charging power to at least ten EV chargers used to charge a fleet of EVs at a single centralized depot location. Controllers connected to the bus system, the power sources (e.g., at service panels), converters (e.g., at rectifiers and inverters connected to the bus system), and EV depot management information can track power usage from each input source, track consumption at each EVSE device, ensure security, load-balance the usage of the input sources to minimize peak-power utility usage demand charges (e.g., demand charges based directly on the highest peak power level consumed within a subdivision of a billing period or based directly on the highest average power level of a subdivision of the billing period), respond to grid signals for demand response events, provide emergency operations in case of grid-level outages using local energy storage and generator, and, for networks of connected controllers, react in a unified manner to various needs and events. An example embodiment can be configured to serve 1 Megawatt of demand with an aggregated 500 kilowatts of capacity (as an indication of ratio) through a combination of aggregating unused power capacity, providing power from energy storage (e.g., in a “surging” capacity), and using software-controlled load balancing, all without needing a utility service upgrade. 
     In some embodiments, a method and system are provided that physically aggregate electrical points of common coupling (PCC) with generally current-constrained electrical panels to allow for the energization and utilization of one or multiple high-power loads, such as EVSEs (e.g., EV chargers). To accomplish this, multiple electrical sources can be connected together through a series of power electronics that enables the sources to effectively be turned “on” or “off” (to the bus) by a controller. Any sources that are turned “on” simultaneously enable an aggregate combined output to be available to the EVSE devices. In specific topologies where energy storage is utilized, an added benefit of allowing finite duration “bursts” of power can be supported based on storage capacity size and EVSE demand. 
     Each electrical source can be individually monitored upstream to prevent tripping of over current protection devices or achieving power demand levels above desired thresholds. The available power margin for each source of power based on at least one of: the electrical service capacity (e.g., based on demand of active loads at the site), an optimized peak demand threshold (e.g., using customer- or system-controller-defined constraints such as tariff, time of use (e.g., time-of-use pricing), and peak demand charge information), main over current trip rating in power, and breaker trip rating used to connect to the aggregate power network/bus. Once an electrical source is enabled, power conversion devices can be used to pull power from the source at a desired level or up to the maximum allowed level, or, signals can be sent to the downstream loads (e.g., EVSEs) to curtail the maximum power draws to the maximum allowed level. 
     In embodiments where an ESS is employed, the power that is drawn from each source can be stored by the ESS, and the utilization of the energy can be controlled as a second stage event that occurs separate and independent of the event of drawing power from the sources. 
     The present description provides examples, and is not limiting of the scope, applicability, or configuration set forth in the claims. Thus, it will be understood that changes may be made in the function and arrangement of elements discussed without departing from the spirit and scope of the disclosure, and various embodiments may omit, substitute, or add other procedures or components as appropriate. For instance, the methods described may be performed in an order different from that described, and various steps may be added, omitted, or combined. Also, features described with respect to certain embodiments may be combined with or included in other embodiments. 
       FIG.  1 A  is a block diagram of an electric vehicle charging system  100 . The system  100  can include a first utility grid connection  102  and a second utility grid connection  104 . Each grid connection  102 ,  104  can be connected to an electrical service panel  106 ,  108 . The electrical service panels  106 ,  108  can be connected to one or more electric service sub-panels (e.g.,  110 ,  112 ,  114 ). The electrical service panels  106 ,  108  can be connected to an electrical bus system  120  which is connected to an output panel  122  (or directly to EVSE devices/EV chargers). The output panel  122  can be connected to EVSE devices/EV chargers such as, for example, chargers connectable to or carried by an EV  124 . 
     The utility grid connections  102 ,  104  can include service connections to an electrical utility distribution grid. System  100  comprises two utility grid connections  102 ,  104 , but additional grid connections, or a single grid connection, can be used in the system  100 . For instance, any additional grid connection can be connected to the bus system  120  in parallel to the other grid connections  102 ,  104 . The grid connections  102 ,  104  can comprise capability ratings and electrical characteristics that are different from each other. In some embodiments, the grid connections  102 ,  104  can provide different voltages (e.g., 480 volt grid service from grid connection  102  and 208 volt grid service from grid connection  104 ), different alternating current (AC) signals (e.g., single phase grid service (each having the same or different voltages) or three phase grid service (each having the same or different voltages)), different current ratings, and different usage grades or permits from the utility provider. For example, one grid connection can be an industrial-, commercial-, or non-residential grade utility connection and another grid connection can be a residential-, non-industrial-, or non-commercial grade utility connection. 
     The type and characteristics of the grid connections  102 ,  104  of the system can be determined or monitored by a controller (see e.g.,  FIG.  3   ), and the controller can be capable of managing and controlling the system  100  in different ways based on the type and characteristics determined or monitored. For example, an industrial grid connection may be capable of participating in a demand response program with a utility provider whereas a residential grid connection may not be permitted to participate in such a program. Similarly, a commercial grid connection may be subject to different billing practices as compared to a residential grid connection, such as the commercial grid connection being subject to peak rates or peak usage demand charges that are not assessed to customers using a residential grid connection. Notably, the grid connections  102 ,  104  of the system  100  can be part of a single customer&#39;s site or can be owned and/or operated by a single utility customer. In some embodiments, the grid connections  102 ,  104  can be operated by multiple customers or located at multiple customers&#39; sites (e.g., at least two customers&#39; sites). Thus, the system  100  can aggregate multiple sources from a single utility customer or can aggregate sources from multiple utility customers. In this manner, the system  100  can be used to improve usability of systems with multiple service connections, including mismatched connections, even if the systems are used by different utility customers or are underutilized by a single customer. In some embodiments, the grid connections  102 ,  104  can each comprise a utility meter configured to track consumption of energy and/or power from the utility grid to which they are connected. 
     The service panels  106 ,  108 ,  110 ,  112 ,  114  can be utility service panels used to provide control and limits on the usage of the electrical utility service connections or other power sources to which they are connected. In some embodiments, a single service panel (e.g.,  106  and  108 ) is in electrical communication with a respective different grid connection (e.g.,  102  and  104 ) and with the bus system  120 , and there are no intervening sub-panels (e.g.,  110 ,  112 ,  114 ). In other cases, the sub-panels  110 ,  112 ,  114  are included and further control and limit the provision of power from a panel (e.g.,  108 ,  110 ) to the bus system  120 . The service panels  106 ,  108 ,  110 ,  112 ,  114  can each have a rating, trip level, power or current capacity, or other similar electrical characteristic indicating their capability for providing power to loads connected to the panel. For instance, panel  106  can have an 800-amp rating, panel  108  can have a 1000-amp rating, panel  110  can have a 600-amp rating, panel  112  can have a 400-amp rating, and panel  114  can have a 400-amp rating. Accordingly, those ratings represent the maximum amps that can be drawn from each respective panel. Generally, higher-rated panels can be electrically connected closer in a circuit to the grid service connections  102 ,  104 , and lower-rated panels can positioned electrically further from the grid service connections  102 ,  104 , such as by being connected as a sub-panel to another panel. 
     Each of the service panels  106 ,  108 ,  110 ,  112 ,  114  can comprise a set of circuit breakers (e.g.,  116 ,  118 ) configured to be connected to loads or energy sources at the customer site. The breakers can be configured to limit the power level provided to those loads or sources relative to the overall rating of the respective service panels (e.g.,  106 ,  112 ) to which they are connected. For example,  FIG.  1 A  shows that breaker  116  can have a 300-amp capacity while the service panel  106  has an up to 800-amp capacity. In some embodiments, the service panels have a plurality of breakers that may have individual capacities that, when combined, exceed the overall rating of the service panel to which they are connected. Breaker  116  has an 800-amp rating, but its individual breakers (e.g.,  116 ) are shown with a combined capacity of 1200 amps. A similar situation applies to panels  108 ,  110 , and  112 . Service panel  114  comprises breakers having a combined capacity equal to the capacity of the panel  114 , but it may still be undesirable to draw power at the full rated capacity of the breakers due to fluctuations in demand that could drive consumption beyond the panel&#39;s rating, thermal issues, measurement error, and other concerns. Accordingly, not all of the breakers can be used to maximum capacity at all times, and the bus system  120  can be controlled to avoid exceeding service panel ratings while also preventing exceeding individual breaker capacity. To do so, power meters (e.g., ammeters) can be configured to measure consumption at each of the panels  106 ,  108 ,  110 ,  112 ,  114 , and those meters can provide their measurements to the controller connected to the bus system. In some embodiments, power meters are configured to measure consumption only at the service panels directly connected to the bus system  120  (e.g., panels  106 ,  112 , and  114 ) since the power drawn via the bus system  120  directly affects those panels. 
     The bus system  120  can comprise a plurality of converters (e.g., rectifiers and inverters), a direct current (DC) voltage bus, energy storage systems, and generator systems. See  FIG.  2    and its related descriptions herein. 
     The output panel  122  can comprise a service panel with its power supplied by the bus system  120 . The output panel  122  can therefore be indirectly powered by the utility grid since it has no direct connection to a power source such as the grid connections  102 ,  104 . The output panel  122  can be connected to (or part of) an electric vehicle charging system (e.g., EVSE) configured to output power to connected EVs (e.g.,  124 ) through one or more charging stations. Charging equipment can have individual breakers that can be monitored and managed by a controller to ensure that the service capacity of the output panel  122  is not exceeded. Loads and devices can be monitored by power meters connected at the loads or to their breakers/service panels from which they receive power. 
       FIG.  1 B  shows an alternative embodiment of a system  126  similar to system  100 . For convenience, elements of system  126  having similar names to elements of system  100  can have the same characteristics and features, subject to any differences described below. Thus, system  126  can include a set of utility grid connections  128 ,  130  connected to a set of service panels  132 ,  134 ,  136  having sets of breakers. The system  126  can also comprise a generator  138  and/or energy storage systems  140 ,  142  connected to the bus system  120  with an output panel  122  for providing charge to electric vehicles. The energy storage systems  140 ,  142  and generator  138  are optional devices for the operation of the system  126  and can individually or collectively excluded based on customer and operator needs. In some embodiments, these devices  138 ,  140 ,  142  can also be reconfigured, such as in a case where the generator  138  is connected to a service panel (e.g.,  134 ), to an energy storage system (e.g.,  142 ), to the output panel  122 , etc. In some embodiments, an energy storage device can be used in place of the bus system  120 , and the energy storage device&#39;s internal bus can be used as the bus system for the overall EV charging system  126 . 
     The generator  138  can comprise a local generator at the customer site that is configured to provide power to the bus system  120 . The generator  138  can be fuel-based, such as a diesel generator, and can be configured to use the fuel to produce power at the command of the customer and/or in response to operation of a system controller. 
     The energy storage systems  140 ,  142  can comprise one or more energy storage devices configured to charge to store energy provided by the grid connections  128 ,  130  or generator  138  (e.g., via the electrical connection between bus system  120  and the grid connections  128 ,  130  or generator  138 ). The energy storage systems  140 ,  142  can also be operated to discharge energy to the bus system  120  to provide power to the output panel  122 . In some embodiments, the energy storage systems  140 ,  142  can comprise battery, flywheel, capacitor/super-capacitor devices, related devices, and combinations thereof. The energy storage systems  140 ,  142  can be controlled to charge to “absorb” excess power provided to the bus system  120  when demand at the output panel  122  is lower than the power provided to the bus system  120  from other sources. An ESS can be controlled to discharge to supplement the power provided to the bus system  120  when demand at the output panel  122  exceeds power provided from other sources. In this manner, the energy storage systems  140 ,  142  can improve the consistency and reliability of power provided from the bus system  120  to the output panel  122 . Additionally, the energy storage systems  140 ,  142  can be used to feed power to the grid connections  128 ,  130  for implementing energy arbitrage, load leveling, demand response, frequency response, and other related cost savings activities. 
     As shown in  FIG.  1 B , an energy storage system  140  can be positioned electrically between or in series with a grid connection  130  and associated service panels  134 ,  136 . The ESS  140  can thereby be charged directly from a breaker of a service panel (e.g.,  136 ) and, in some cases, can directly provide power back to the service panels  136 ,  134  and their associated grid connection  130 . In this configuration, the ESS  140  can provide consistent power to the bus system  120  by using its energy storage capacity to compensate for lags or surges in available power from the grid connection  130  or related service panels  134 ,  136 . 
       FIG.  1 B  also shows an energy storage system  142  connected directly and solely to the bus system  120 , thereby illustrating that an ESS  142  can be charged and discharged solely and directly by the bus system  120 . See also ESS  214  of  FIG.  2   . With this configuration, the ESS  142  can be used to stabilize the power output of the bus system  120  to the output panel  122  or to other connected devices (e.g., ESS  140  or devices connected to panel  132 ) and can be used to collect and store energy from multiple sources (e.g.,  128 / 132  and  138 ) for faster and higher-capacity charging as compared to an ESS  142  only connected to one power source. 
       FIG.  2    is a block diagram of a bus system  200  according to an embodiment of the present disclosure. The bus system  200  can be an embodiment of the bus system  120  of  FIGS.  1 A and  1 B . The bus system  200  can include a DC bus  202  configured to connect to at least one source connection  204 ,  206 ,  208  directly (as in source connection  206 ) or one or more power converters  210 ,  212  (as represented in this example by rectifiers). The bus system  200  can also include an energy storage system  214  and generator  216  directly electrically connected to the DC bus  202 . The DC bus  202  can also be connected to a power converter (e.g., inverter  218 ) configured to convert an output signal to an output connection  220 . 
     The DC bus  202  can be a high voltage bus configured to facilitate transfer of power from the multiple source connections  204 ,  206 ,  208 ,  214 ,  216  (e.g., via power converters  210 ,  212 ) to the inverter  218 . The DC bus  202  can therefore have a voltage to which the various connected devices are converted or maintained to ensure the compatibility and stability of the DC bus  202 . 
     The source connections  204 ,  206 ,  208  can be connections to service panels (e.g.,  106 ,  112 ,  114 ,  132 ) or other power sources (e.g., ESS  140 , ESS  142 , or generator  138 ). When a source provides an AC signal to a source connection, a rectifier (e.g.,  210 ,  212 ) can be used to convert the AC signal to a DC signal compatible with the DC bus  202 . In some embodiments, the power converters  210 ,  212  can be DC-DC step up/step down converters, phase converters, similar devices, and combinations thereof as needed to ensure that a signal from a source connection is properly compatible with the DC bus  202 . Additionally, in some cases, a power converter can be omitted for at least one source connection (e.g.,  206 ) due to the source being configured to output a signal having directly compatible electrical characteristics (e.g., the same voltage) with the DC bus  202 . The inverter  218  can be a DC-to-AC inverter that provides an AC output to the output connection  220 , which in turn can provide AC output to an output panel (e.g.,  122 ) or EVSE. 
     The bus system  200  can thus include a number of converters and different kinds of control equipment that manages and combines the signals coming from multiple source connections  204 ,  206 ,  208  to provide high power to an output connection  220 . In some embodiments, the power provided to the output connection  220  is therefore a summation of the power provided from the source connections  204 ,  206 ,  208 . Furthermore, the bus system  200  can be used to at least temporarily provide higher power than would be possible using only the source connections  204 ,  206 ,  208  by supplementing that power with output from the energy storage system  214  and/or generator  216 . Accordingly, the bus system  200  can enable charging of fleets of electric vehicles at a site where individual service panels and grid connections are insufficient to power one or more EVSE devices simultaneously due to aggregation and combination of the power sources followed by providing a unified (and, in some cases temporarily boosted and amplified) output signal. 
     Control of the bus system  200  can be provided by a controller  300  such as the controller illustrated in the block diagram of  FIG.  3   . The controller  300  can be a computing device in electrical communication with various other components of the systems  100 ,  126 ,  200  described herein, as indicated by the dashed-line connections in  FIG.  3    that link the controller  300  to meters  302 , panels  304 , rectifiers  306 , inverters  308 , and energy storage and/or generation system  310 . Connections can be added or removed to adapt the controller  300  to the scale and number of systems at a given customer&#39;s site. The meters  302  can comprise ammeters or other power meters configured to measure energy consumption from the grid or other power sources at the customer site(s) monitored and controlled with the controller  300 . Meters  302  can also be installed at various points in the system, including at an ESS, at a generator, at the bus system or power converters, at the output panel  122 , at EVSE, etc. to track the operation and usage of each component as needed to maintain consistent operation, to react to changes in loads and supply, and to track and store usage data over time for later analysis and forecasting. The panels  304  can be service panels or breakers that are monitored by the controller  300  (e.g., the service panels and breakers of  FIGS.  1 A and  1 B ). The rectifiers  306  and inverters  308  can comprise one or more of the power converters shown and described in connection with  FIG.  2   , and the energy storage and/or generation system  310  can comprise one or more of the energy storage systems and generators described in connection with  FIGS.  1 B and  2   . 
     The controller  300  can be configured to receive and/or send signals to each of the devices to which it is connected. In some embodiments, the controller  300  can receive usage indication signals from the meters  302 , panels  304 , rectifiers  306 , inverters  308 , and/or energy storage systems/generation systems  310 . In this manner, the controller  300  can monitor various points in the systems  100 ,  126  described above to determine how much of the rated capacity of the service panels, grid connections, energy storage systems, generators, etc. is being used on a consistent (e.g., real-time) basis and can use that information to determine how much power to draw from the service panels, energy storage systems, generators, etc. (e.g., via the rectifiers  306  or other power converters connected to the controller  300 ). The controller  300  can also use that information to manage how much power is provided to an output panel (e.g.,  122 ) so that EVs and EVSE devices can be controlled to charge at rates that will be achievable based on the power available from the various source connections, ESS, and generators. 
     The controller  300  can also be in electrical communication with a network  312  and a data repository  314 . The network  312  can be a computer network, such as a utility grid communications network (e.g., the Internet, a local area network, a wide area network, etc.) used for communicating demand response and other grid participation requests and commands from a utility-level demand response manager or clearinghouse. Thus, the controller  300  can receive and respond to these signals by adjusting the available power for EV charging or redirecting power from an ESS or generator to the grid as needed or desired. In some embodiments, the network  312  can connect the controller  300  to a controller for another system like system  100  or  126 . In this manner, the controller  300  can interact with other controllers to coordinate power output, schedule charging or other power usage based on EV usage forecasts, track efficiency, aggregate usage statistics, etc. The data repository  314  can comprise one or more electronic storage devices or databases connected to the controller  300 . In some cases, the data repository  314  can store information about the system to which the controller  300  is connected, such as by containing information about the power ratings or capacities of the panels  304 , rectifiers,  306 , inverters  308 , other converters, and ESS/generator  310 . Thus, the controller  300  can access the data repository  314  to compare the measured electrical characteristics of those devices (e.g., the power usage of a breaker as determined by a meter (e.g.,  302 )) to the rated characteristics of those devices (e.g., the rating of the breaker) to calculate an available power characteristic for the devices, converters, or other assets. 
     The controller  300  can comprise a computing system made of a plurality of computing devices configured to control and monitor the electric vehicle charging systems and related components described herein. A controller  300  can therefore be used to monitor electrical sources and make decisions (based on a set of electronic instructions) that are based on known constraints (e.g., panel or ESS throughput ratings), desired outputs (e.g., maintaining a desired output kW to the output panel  122 ), and real time measurements read and reported by meters  302  (e.g., the present consumption at a panel or the amount of power being converted at a rectifier). Decisions of the controller  300  can be implemented by sending signals to power converters, controllable/curtailable loads, and other auxiliary systems to enable or disable a power source and to match the aggregate supply with the aggregate load. 
     High accuracy electrical meters can be used that help measure real-time loads and conditions for each power source. The readings from these meters can give the controller accurate and precise data points enabling the controller to make decisions quickly enough to prevent open circuit protection (OCP) devices from tripping or power thresholds from being violated. In some embodiments, meters can be used that push signals to controllers to mitigate timing issues, and a controller can poll the meter for data with some latency introduced in the poll interval or data conversion or processing within the meter. An event-driven signal that is triggered on the cycle basis to shed load can be used to prevent a trip of OCP devices. In addition, OCP devices can be programmable to include a trip delay to allow for some toleration of over currents based on the magnitude or time of the detected currents. 
     Converters (e.g., rectifiers) can be push/pull type and can be used with an ESS based on commands and targets determined by the controller  300 . The converters can thereby act as a controlled electrical “gate” enabling precise power flow to be commanded or allowed from specific sources at specific times. 
     The ESS can comprise a DC bus and can be capable of storing energy. The ESS can be used as a buffer by the controller  300  to break dependency of real-time loads from needing to exactly match the supply (or vice versa). In some embodiments, the DC bus can include an externally-controllable DC-DC converter or an exposed system that can provide “gate”-like control functionality to the controller connected to the DC bus. 
     Controllable loads (e.g., connected to the panels  304  or connected directly to the controller  300 ) can be configured to receive signals from the controller to become aware of available (or deficient) upstream power. Thus, the controllable loads can be operated by the controller  300  to help limit or increase available supply or demand on the DC bus system. 
     Using the controller  300  can enable dynamic monitoring and balancing of local power supply and demand at a micromanaging, individual load (or source) level with load curtailments.  FIG.  5    illustrates an embodiment showing component parts and relationships of an example controller system, as explained in further detail below. 
       FIG.  4    shows a flow diagram of illustrating embodiments of a process  400  or executable instructions that can be performed by the systems described herein. In some embodiments, the process  400  can be performed by a controller (e.g.,  300 ) in connection with other components of one or more systems described herein. The process  400  can include determining available power, as indicated in block  402 . The available power can be determined for various power sources at the customer site, such as for each grid connection (e.g.,  102 ,  104 ,  128 ,  130 ), each service panel (e.g.,  106 ,  108 ,  110 ,  112 ,  114 ,  132 ,  134 ,  136 ), each breaker (e.g.,  116 ,  118 ), each generator (e.g.,  138 ,  216 ), each ESS (e.g.,  140 ,  142 ,  214 ), and/or each power converter (e.g.,  210 ,  212 ,  218 ). 
     In some embodiments, available power for a device (i.e., power margin) can be defined as an amount of unused capacity for that device. For example, the available power can be the difference between the rated capacity of a breaker and the currently-used capacity of the breaker. In some embodiments, available power can be determined based on electrical service capacity of a grid connection or the site as a whole or a main over-current trip rating (in power levels or current measurements). In some embodiments, available power can be further modified based on user preferences (e.g., rather than using the rated capacity (i.e., trip rating)), the available power can be determined by using a user-defined maximum power on a system-wide or per-device basis), utility mandates (e.g., utility-defined reserve limits for the device in question), forecasts (e.g., saving capacity for anticipated consumption fluctuations or future planned consumption), related elements, and combinations thereof In one example, available power can be defined in part by forecasted or planned consumption at the output panel  122 , such as when EVs are scheduled to connect to and charge at EVSE devices. 
     In some embodiments, available power can be defined based on economic constraints such as limits that change in response to tariff, time-of-use pricing, or peak demand charge levels. For instance, available power from an ESS can be limited when peak demand charge-incurring power levels for a subdivision of a billing period have been approached by the system so that future demand charges can be mitigated by the ESS. Some of these optional alternative inputs are indicated in block  403 . Available power from an ESS can also be modified (e.g., reduced) when the ESS is expected to enter an inefficient state of charge, temperature, state of health, or other detrimental condition wherein using the ESS could be dangerous or deleterious to the future capacity or effectiveness of the ESS in the system. In some embodiments, the available power can be defined as an amount of available power over time, such as a forecasted available power over an upcoming period of time, as indicated in optional block  405 . The available power determined in block  402  can therefore change over time, and an anticipated available power can be used to take actions in advance, as described in further detail below. 
     In some configurations, available power can be determined on a per-source level, wherein available power of each source connection to a bus system can be calculated before being combined together in block  402 . Individual available power values for individual units can be controlled to adjust the way the process  400  uses each unit. For example, the available power for a first power source and the available power for a second power source can be controlled to ensure that the first power source is used prior to the second power source (or vice versa), that output rates from each power source ramp at certain speeds or with certain timing, or that similar timing and sequence commands are followed. Similarly, the ramp rates for first and second power sources can be controlled so that, for example, one source ramps more quickly or more slowly than another source so that their maximum output stages do not, at least initially, overlap each other, thereby ensuring that the electrical constraints on the bus system are kept within desired tolerances. 
     The process  400  can also include determining load demand, as indicated in block  404 . The load demand can refer to the level of demand that is needed (or will imminently be needed) at the output panel  122  or EVSE devices. Thus, the load demand determined can include a demand for EV charging at the site, such as by detecting an EV connected to the site, detecting how much power it is requesting to use to charge, forecasting the arrival of an EV or segment of a fleet of EVs, etc. This load demand can be determined based on power draw of loads (e.g., EVs) connected to the output panel  122  or at service panels and breakers (e.g., in systems  100  and  126 ). The load demand can be a real-time determined value (e.g., amps being used by a particular set of breakers at a particular time) or can be a forecasted set of current and future values (as indicated by block  407 ). Additionally, the process  400  can include determining control granularity, nameplate values, and ramp rates to help determine the load demand for one or more loads on the system, as indicated in block  409 . 
     The process  400  can then include determining whether sufficient power is available, as shown in block  406 . In some embodiments, this includes determining whether the current or expected available power is greater than the current or expected load demand. If sufficient power is available, the process  400  can include commanding the bus system to implement a conversion, as shown in block  408 . The conversion can include controlling converters (e.g., rectifier(s)) to draw power from source connections and controlling converters (e.g., inverter(s)) to supply the power needed to meet the load demand determined in block  404 , as indicated in block  410 . In some embodiments, block  408  can also include drawing power from source connections to charge an ESS from the bus in block  410  or sending a signal to a generator to provide power to the system (e.g., to the DC bus system) that is distributed to the output panel  122  or to an ESS. 
     When sufficient power is not found in block  406 , the process  400  can include modifying the available power, as shown in block  412 . Such modification can include shedding, curtailing, or otherwise controlling demand of controllable loads or increasing available power by providing power from a generator or ESS. After modification of the available power, the process can proceed with commanding conversion to the bus in block  408  with an expectation that the conversion in block  408  would not cause problems for the panels, bus system, and other connected components. 
       FIG.  5    shows a high-level block diagram of a computer system  500  for embodiments of the present disclosure. In various embodiments, the computer system  500  can comprise various sets and subsets of the components shown in  FIG.  5   . Thus,  FIG.  5    shows a variety of components that can be included in various combinations and subsets based on the operations and functions performed by the system  500  in different embodiments. For example, the computer system  500  can be used as at least part of the controller  300  of  FIG.  3   . It is noted that, when described or recited herein, the use of the articles such as “a” or “an” is not considered to be limiting to only one, but instead is intended to mean one or more unless otherwise specifically noted herein. 
     The computer system  500  can comprise a central processing unit (CPU) or processor  502  connected via an electronic communications bus  504  for electrical communication to a memory device  506 , a power source  508 , an electronic storage device  510 , a network interface  512 , an input device adapter  516 , and an output device adapter  520 . For example, one or more of these components can be connected to each other via a substrate (e.g., a printed circuit board or other substrate) supporting the bus  504  and other electrical connectors providing electrical communication between the components. The bus  504  can comprise a communication mechanism for communicating information between parts of the system  500 . Thus, as used herein, a first component can be in “electrical communication” with a second component when the components are capable of one-way or bidirectional transfer of electrical signals between each other. In some cases, the electrical communication includes the transfer of relatively low-power control or monitoring signals (e.g., as in the components shown in  FIGS.  3  and  5   ), and in some cases, the electrical communication includes the transfer of higher power line signals (e.g., as in the components shown in systems  100 ,  126 , or  200 . 
     The processor  502  can be a microprocessor or similar computing device configured to receive and execute a set of executable instructions  524  (e.g., a computer program) stored by the memory  506 . The memory  506  can be referred to as main memory and can comprise components such as random access memory (RAM) or another dynamic electronic storage device for storing information and instructions to be executed by the processor  502 . The memory  506  can also be used for storing temporary variables or other intermediate information during execution of instructions executed by the processor  502 . The storage device  510  can comprise read-only memory (ROM) or another type of static storage device coupled to the bus  504  for storing static or long-term (i.e., non-dynamic) information and instructions for the processor  502 . For example, the storage device  510  can comprise a magnetic or optical disk (e.g., hard disk drive (HDD)), solid state memory (e.g., a solid state disk (SSD)), or a comparable device. The storage device  510  can comprise a data repository  314  of information about electrical devices (e.g., meters, panels, grid connections, ESS, generators, loads, EVSE, etc.) at the customer site. The power source  508  can comprise a power supply capable of providing power to the processor  502  and other components connected to the bus  504 , such as a connection to an electrical utility grid or a battery system. In some embodiments, the power source  508  comprises a connection to a service panel (e.g.,  304 ) that is in electrical communication with a grid connection to power the system  500  via the grid. 
     The instructions  524  can comprise information for executing processes and methods using components of the system  500 . Such processes and methods can include, for example, the methods described elsewhere herein, such as, for example, the processes described in connection with  FIG.  4   . 
     The network interface  512  can comprise an adapter for connecting the system  500  to an external device via a wired or wireless connection. For example, the network interface  512  can provide a connection to a computer network  526  such as a cellular network, the Internet, a local area network (LAN), a separate device capable of wireless communication with the network interface  512 , network  312 , other external devices or network locations, and combinations thereof. In one example embodiment, the network interface  512  is a wireless networking adapter configured to connect via WI-FI®, BLUETOOTH®, BLE, Bluetooth mesh, or a related wireless communications protocol to another device having interface capability using the same protocol. In some embodiments, a network device or set of network devices in the network  526  can be considered part of the system  500 . In some cases, a network device can be considered connected to, but not a part of, the system  500 . 
     The input device adapter  516  can be configured to provide the system  500  with connectivity to various input devices such as, for example, a keyboard  514 , touchpad, or similar user input device, and a set of sensors  528  such as, for example, power meters (e.g.,  302  or part of the rectifier(s)  306  or inverter(s)  308 ), related devices, and combinations thereof. Thus, the sensors  528  can be used to measure and monitor the usage and performance of the electronic devices operated at the customer site and particularly the devices connected to the bus system  120 / 200 . The keyboard  514  or another input device (e.g., buttons or switches) can be used to provide user input such as input regarding the settings of the system  500  such as pricing information, timing preferences, manual limits on usage, EV charging scheduling information, and related information. In some embodiments, such input information can be obtained for the processor  502  via the network  526 . 
     The output device adapter  520  can be configured to provide the system  500  with the ability to output information, such as by providing visual output using one or more displays  532  or indicators  534  or by providing audible output using one or more speakers  535 . Other output devices can also be used, such as output devices that send control signals to controllable loads, EVSE, ESS, and generators that are part of the system. The processor  502  can be configured to control the output device adapter  520  to provide information to a user via the output devices connected to the adapter  520  and can be configured to control other devices via the output device adapter  520 . 
     Various inventions have been described herein with reference to certain specific embodiments and examples. However, they will be recognized by those skilled in the art that many variations are possible without departing from the scope and spirit of the inventions disclosed herein, in that those inventions set forth in the claims below are intended to cover all variations and modifications of the inventions disclosed without departing from the spirit of the inventions. The terms “including:” and “having” come as used in the specification and claims shall have the same meaning as the term “comprising.”