Overcurrent protection for energy storage and power supply system

An energy and power supply device includes an energy storage unit configured to store electrical energy, an output coupled to the energy storage unit and configured to provide an output electrical current to a load, and a current limiting system configured to selectively limit the output electrical current according to a current protection profile. The current protection profile includes a plurality of threshold currents and a plurality of corresponding threshold periods of time that facilitate providing the output electrical current according to a maximum variable current versus time function.

BACKGROUND

An energy storage and power supply device may be used to store power in an energy storage unit. The energy storage unit may store power from a power supply device and provide power to an external device. The power for the external device may be provided at one or more outputs of the energy storage and power supply device.

SUMMARY

One embodiment relates to an energy storage and power supply device. The energy and power supply device includes an energy storage unit configured to store electrical energy, an output coupled to the energy storage unit and configured to provide an output electrical current to a load, and a current limiting system configured to selectively limit the output electrical current according to a current protection profile. The current protection profile includes a plurality of threshold currents and a plurality of corresponding threshold periods of time that facilitate providing the output electrical current according to a maximum variable current versus time function.

Another embodiment relates to an energy storage and power supply device. The energy and power supply device includes an energy storage unit configured to store electrical energy, an output coupled to the energy storage unit and configured to provide an output electrical current to a load device, a regulator positioned along a current flow path between the energy storage unit and the output, and a processing circuit. The processing circuit is configured to at least one of (i) access a plurality of current set points, each of the current set points including a respective threshold current and a corresponding threshold period of time and (ii) determine a respective threshold current based on a corresponding threshold period of time; monitor the output electrical current; and send a signal to the regulator to terminate the output electrical current in response to the output electrical current exceeding the respective threshold current for longer than the corresponding threshold period of time for at least one of the current set points.

Still another embodiment relates to a method for controlling an electrical output current from an energy storage unit at an output of an energy storage and power supply device. The method includes providing, by the energy storage unit, the output electrical current to the output of the energy storage and power supply device; and selectively limiting, by a current limiting system of the energy storage and power supply device, the output electrical current according to a current protection profile. The current protection profile includes a plurality of threshold currents and a plurality of corresponding threshold periods of time that facilitate providing the output electrical current according to a maximum variable current versus time function.

The invention is capable of other embodiments and of being carried out in various ways. Alternative exemplary embodiments relate to other features and combinations of features as may be recited herein.

DETAILED DESCRIPTION

Electrical energy may be transmitted from a power supply device to an energy storage and power supply device for storage in an energy storage unit (e.g., a battery including one or more cells, etc.). The electrical energy may be transmitted from the energy storage and power supply device to various loads devices. By way of example, the energy storage and power supply device may include one or more outputs with which a load device interacts (e.g., using a power cable, etc.) to receive electrical energy. The current provided by the energy storage and power supply device and/or drawn by the load device may vary. By way of example, certain load devices may draw an elevated current level for in initial or startup period of time and thereafter draw a reduced current level.

According to an exemplary embodiment, the energy storage and power supply device includes multi-stage overcurrent protection on the one or more outputs. In one embodiment, the energy storage and power supply device includes an overcurrent protection circuit (e.g., a hardware overcurrent protection circuit, etc.) and a software protection (e.g., a software-based protection, etc.) on the one or more outputs. In other embodiments, the energy storage and power supply device includes a plurality of overcurrent protection circuits and/or a plurality of software protections on the one or more outputs. The overcurrent protection circuit and/or the software protections may be configured to selectively terminate the current flow at the one or more outputs (e.g., to protect the energy storage unit, to protect other electronic components of the energy storage and power supply device, etc.).

The overcurrent protection circuit and/or the software protections on the one or more outputs may be configured to provide a current protection curve or a current protection profile that permits one or more threshold current levels for one or more threshold periods of time (e.g., rather than one or more hard stop points, rather than terminating the flow of current at the output in response to exceeding one or more threshold currents even briefly, etc.). The energy storage and power supply device may thereby accommodate various load devices having current draws that surge at start-up and/or at some point during operation but decrease during normal operation (e.g., an air conditioning unit having a condenser or other component requiring a greater current during startup than during normal operation, etc.). In some embodiments, the current protection curve or the current protection profile is applied separately to alternating current (“AC”) outputs and direct current (“DC”) outputs of the energy storage and power supply device.

According to the exemplary embodiment shown inFIGS. 1 and 2, an energy storage and power supply device (e.g., a solar generator, a hybrid combustion and solar generator, etc.), shown as energy storage and power supply device10, is configured to receive and store electrical power from a power source for future use (e.g., in a remote location where electricity is not readily available, during a power outage, etc.). The power source may include a solar panel system, a combustion generator (e.g., a gasoline-fueled generator, etc.), a power supply (e.g., a 120 Volt (“V”) wall charger, a 220V wall charger, a 240V wall charger, etc.), and/or a 12V car adapter. The stored electrical power may be provided to a load device (e.g., a smartphone, a tablet, an E-reader, a computer, a laptop, a smartwatch, a portable and rechargeable battery pack, appliances, refrigerators, lights, display monitors, televisions, etc.) to at least one of charge and power the load device.

As shown inFIGS. 1 and 2, the energy storage and power supply device10includes a housing, shown as housing20. As shown inFIGS. 1 and 2, the energy storage and power supply device10includes an energy storage unit, shown as battery30. According to an exemplary embodiment, the housing20defines an internal cavity of the energy storage and power supply device10that receives the battery30. The battery30may include one or more lithium-ion cells. In some embodiments, the battery30includes a plurality of batteries (e.g., two or more batteries connected in series, etc.). In some embodiments, the battery30additionally or alternatively includes another type of battery (e.g., a lead-acid battery, etc.) or energy storage unit (e.g., one or more capacitors, etc.).

As shown inFIGS. 1 and 2, the energy storage and power supply device10includes an interface, shown as user interface40. As shown inFIG. 2, the user interface40includes a first portion, shown as first panel42, a second portion, shown as second panel44, and a third portion, shown as third panel46. As shown inFIG. 2, the first panel42includes a first plurality of interfaces, the second panel44includes a second plurality of interfaces, and the third panel46includes a third plurality of interfaces, shown as input/output (“I/O”) ports48. The I/O ports48are electrically coupled to the battery30, according to an exemplary embodiment. According to an exemplary embodiment, (i) at least a portion of the I/O ports48are configured to receive electrical energy from a power source (e.g., a solar panel system, a combustion generator, a power supply, a 12V car adapter, etc.) for storage by the battery30, (ii) at least a portion of the I/O ports48are configured to provide the stored electrical energy within the battery30to a load device (e.g., a smartphone, a tablet, an E-reader, a computer, a laptop, a smartwatch, a portable and rechargeable battery pack, appliances, a refrigerator, lights, display monitors, televisions, etc.) with a power and/or charging cable connected therebetween, and/or (iii) at least a portion of the I/O ports48are configured to receive and provide electrical energy (e.g., operate as dual functioning ports, etc.).

According to the exemplary embodiment shown inFIG. 2, the I/O ports48of the first panel42, the second panel44, and the third panel46include alternating current (“AC”) inverter ports (e.g., having a 110V outlet port, etc.), direct current (“DC”) inputs and/or outputs, USB ports, a 6 millimeter (“mm”) port, a 12V car port, a 12V powerpole port (e.g., an Anderson Powerpole, etc.), a charging port (e.g., a solar panel charging port, a combustion generator charging port, a power supply charging port, a powerpole charging port, etc.), and/or a chaining port (e.g., to electrically couple two or more of the energy storage and power supply devices10in series or parallel, a powerpole chaining port, etc.).

As shown inFIG. 2, the second panel44includes a display, shown as display50. The display50may provide various information regarding the state and/or operation of the energy storage and power supply device10and/or the battery30(e.g., a battery level, a current input power, a current input voltage, a current input current, a current output power, a current output voltage, a current output current, an estimated time until a full charge of the battery30is reached, an estimated time until full and/or permitted depletion of the battery30is reached, a battery temperature, an insignia, a notification, a warning, etc.).

According to the exemplary embodiment shown inFIG. 3, an energy storage and power supply device100(e.g., the energy storage and power supply device10, etc.) is configured to receive electrical power from a device, shown as power supply device300. The power supply device300may be a photovoltaic cell, an array of photovoltaic cells (e.g., solar panel, etc.), a generator (e.g., electrical generator, a combustion generator, etc.), and/or an energy storage unit (e.g., a battery, capacitor, etc.), among other alternatives. The energy storage and power supply device100includes an input, shown as input interface110, and an output, shown as output120. Any of the I/O ports48may provide electrical energy to and/or receive electrical energy from the input interface110and/or the output120. The input interface110is configured to receive electrical energy from the power supply device300. The output120is configured to transmit electrical energy to a device (e.g., a phone, a tablet, a computer, a portable and rechargeable battery pack, etc.), shown as external device400. The external device400may be at least one of charged and powered by the energy storage and power supply device100.

The energy storage and power supply device100further includes a regulator (e.g., a switching regulator, etc.), shown as regulator130, and an energy storage unit (e.g., the battery30, a capacitor, etc.), shown as energy storage unit140. The regulator130may be configured to alter a voltage provided at the input interface110for application to the energy storage unit140. In other embodiments, the energy storage and power supply device100does not include the regulator130. The energy storage unit140may include one or more lithium-ion cells. In other embodiments, the energy storage unit140is or includes another device configured to store energy.

According to the exemplary embodiment shown inFIG. 3, the input interface110is coupled to a circuit, shown as test circuit150. The test circuit150may draw current from the power supply device300in a variable manner. In other embodiments, the energy storage and power supply device100does not include the test circuit150.

As shown inFIG. 3, the energy storage and power supply device100includes a processing circuit160. The processing circuit160is coupled to various components of the energy storage and power supply device100. In one embodiment, the processing circuit160is configured to send and receive information (e.g., current data, voltage data, electrical power data, etc.) to and/or from various components of the energy storage and power supply device100.

According to an exemplary embodiment, the processing circuit160is coupled to the regulator130and the test circuit150. In one embodiment, the processing circuit160is configured to provide commands to the test circuit150such that the test circuit150draws more or less current from the power supply device300and thereafter determine a maximum available input power associated with the power supply device300. The processing circuit160may be configured to control the charging power applied to the energy storage unit140(e.g., by controlling the regulator130, etc.) and/or control the output power at the output120(e.g., by controlling the regulation of the voltage at the output120, etc.) such that the charging power and/or the output power approach or equal the maximum available input power associated with the power supply device300.

The processing circuit160includes a processor, shown as processor170, and a memory (e.g., RAM, ROM, Flash Memory, hard disk storage, etc.), shown as memory180. The processor170may be implemented as a general-purpose processor, an application specific integrated circuit (“ASIC”), one or more field programmable gate arrays (“FPGAs”), a digital signal processor (“DSP”), a group of processing components, or other suitable electronic processing components. The memory180may include multiple memory devices. The memory180may store data and/or computer code for facilitating the various processes described herein. Thus, the memory180may be communicably connected to the processor170and provide computer code or instructions to the processor170for executing the processes described in regard to the processing circuit160herein. Moreover, the memory180may be or include tangible, non-transient volatile memory or non-volatile memory. Accordingly, the memory180may include database components, object code components, script components, or any other type of information structure for supporting the various activities and information structures described herein.

The memory180includes various modules for completing the activities described herein. According to an exemplary embodiment, the processing circuit160includes a first module, shown as display module182and a second module, shown as overcurrent protection module184. In other embodiments, the processing circuit160includes additional, fewer, and/or different modules. The display module182and the overcurrent protection module184may be configured to receive inputs relating to various data and/or information (e.g., current data, voltage data, electrical power data, etc.) and provide output signals. In one embodiment, the processing circuit160analyzes the output signals (e.g., with the processor170, etc.) and controls one or more components of the energy storage and power supply device100.

The processing circuit160is coupled to a number of sensors (e.g., gauges, meters, etc.), according to the exemplary embodiment shown inFIG. 3. The sensors may be associated with the input interface110, the output120, the energy storage unit140, the power supply device300, and/or the external device400. According to the exemplary embodiment shown inFIG. 3, the processing circuit160is coupled to a first sensor, shown as input current sensor192(e.g., positioned to monitor a current of the electrical power provided to the input interface110from the power supply device300, etc.), a second sensor, shown as input voltage sensor194(e.g., positioned to monitor a voltage of the electrical power provided to the input interface110from the power supply device300, etc.), a third sensor, shown as output current sensor196(e.g., positioned to monitor a current of the electrical power provided to the output120and/or the external device400, etc.), and a fourth sensor, shown as output voltage sensor198(e.g., positioned to monitor a voltage of the electrical power provided to the output120and/or the external device400, etc.). In other embodiments, the processing circuit160includes a different combination of sensors and/or still other types of sensors. In still other embodiments, the processing circuit160includes a combination of electrical components (e.g., diodes, resistors, capacitors, etc.) that replace and/or supplement at least one of the input current sensor192, the input voltage sensor194, the output current sensor196, and the output voltage sensor198.

According to the exemplary embodiment shown inFIG. 3, the energy storage and power supply device100includes a circuit, shown as overcurrent protection circuit200. In one embodiment, the overcurrent protection circuit200is a hardware overcurrent protection circuit including a plurality of electrical components that cooperate to provide overcurrent protection. As shown inFIG. 3, a current flow may be provided from the energy storage unit140to the output120. In one embodiment, the overcurrent protection circuit200is disposed along a current flow path between the energy storage unit140and the output120. By way of example, the overcurrent protection circuit200may be configured to receive electrical energy from the energy storage unit140and selectively transmit electrical energy to the output120.

The overcurrent protection circuit200may be configured to selectively terminate the current flow to the output120. In one embodiment, the overcurrent protection circuit200is configured to selectively terminate the current flow at the output120independently (e.g., without relying on and/or receiving command signals from the processing circuit160, etc.). In other embodiments, the overcurrent protection circuit200is coupled to (e.g., communicates with, etc.) the processing circuit160. In one embodiment, the energy storage and power supply device100(e.g., the overcurrent protection circuit200, etc.) is configured to wait a period of time after terminating the current flow to the output120before again permitting the flow of current to the output120.

According to an exemplary embodiment, the overcurrent protection circuit200includes one or more current limiters. By way of example, the current limiters may include one or more electrical components arranged to provide the overcurrent protection outlined herein. A threshold current level and a threshold period of time may be associated with each of the current limiters. The current limiters may be configured to terminate the current flow to the output120in response to the current flow at the output120(e.g., the current draw by the external device400, etc.) exceeding the threshold current level for a duration that reaches or exceeds the threshold period of time. In other embodiments, the overcurrent protection circuit200includes one current limiter configured to terminate the current flow to the output120in response to the current flow at the output120exceeding one of various threshold current levels for a duration that reaches or exceeds corresponding threshold periods of time. The overcurrent protection circuit200may facilitate operating the energy storage and power supply device100according to a variable maximum current versus time function.

By way of example, the overcurrent protection circuit200may include a first current limiter having a threshold current level of 10 Amperes (“Amps”), a second current limiter having a threshold current level of 25 Amps, and a third current limiter having a threshold current level of 50 Amps. The first current limiter, having threshold current level of 10 Amps, may have a threshold period of time of 100 seconds. The second current limiter, having a threshold current level of 25 Amps, may have a threshold period of time equal to 20 seconds. The third current limiter, having a threshold current level of 50 Amps, may have a threshold period of time equal to 2 seconds. The one or more current limiters may thereby cooperate to provide overcurrent protection at the output120according to a current protection curve or a current protection profile (e.g., defined by the series of steps or threshold currents and corresponding threshold periods of time, etc.). One exemplary current protection curve or current protection profile is provided below. In other embodiments, the overcurrent protection circuit200has more or fewer current limiters and/or the current limiters have different threshold current level and/or threshold period of time settings.

During use of the energy storage and power supply device100, the current flow at the output120(e.g., the current draw by the external device400, etc.) may vary. By way of example, the current flow at the output120may be 55 Amps during an initial startup period of the external device400(e.g., for a startup period of time of 5 seconds, etc.). The 55 Amp current draw during the initial startup period may exceed the threshold current level of the first current limiter (e.g., 10 Amps, etc.), the second current limiter (e.g., 25 Amps, etc.), and the third current limiter (e.g., 50 Amps, etc.). Because the 55 Amp current draw exceeds the 50 Amp threshold current level of the third current limiter, the third current limiter is configured to terminate the flow of current to the output120in response to the initial startup period exceeding the 2 second threshold period of time associated with the third current limiter, according to one example. In other words, the third current limiter may thereby continue to permit the flow of current to the output120until the 50 Amp threshold current level is exceeded for 2 or more seconds.

The third current limiter may also continue to permit the flow of current to the output120in response to the 55 Amp current draw falling below the 50 Amp threshold current level. While the 25 Amp and 10 Amp threshold current levels of the second current limiter and the first current limiter, respectively, would also be exceeded by the exemplary 55 Amp current draw, the second current limiter and the first current limiter may not terminate the flow of current to the output120where the third current limiter has already done so (i.e., the threshold periods of time for the second current limiter and the first current limiter may not be reached before the flow of current is terminated by the third current limiter, etc.). In other embodiments, each of the current limiters engage to interrupt the flow of current to the output120in response to flow of current exceeding their respective threshold current levels for the corresponding threshold periods of time.

While the third current limiter may be configured to not interrupt the flow of current in response to the exemplary 55 Amp current draw falling below the 50 Amp threshold current level within 2 seconds, the second current limiter may be configured to terminate the current flow in response to the current draw exceeding 25 Amps for a period of 10 seconds. By way of example, the second current limiter may be configured to terminate the current flow to the output120in response to a current draw of 55 Amps for a period of 1 second and a current draw of 30 Amps for 9 seconds. In other words, the threshold periods of time for the various current limiters may begin to elapse simultaneously where the current draw exceeds the corresponding threshold current levels.

While the foregoing example describes an exemplary current draw during an initial startup period of time, the overcurrent protection circuit200may be configured to terminate the flow of current to the output120at any point during use of the energy storage and power supply device100in response to a current draw exceeding any one of the threshold current levels for the threshold periods of time (e.g., the threshold periods of time initializing at any point during the use of the energy storage and power supply device100, etc.). In still other embodiments, the overcurrent protection circuit200is otherwise configured to terminate the flow of current to the output120based on current draw and time (e.g., in response to an integral of a current draw versus time profile exceeding a threshold level, using an algorithm, etc.).

In response to the current flow at the output120initially exceeding the threshold current and thereafter falling below the threshold current level (falling below the threshold current level within the threshold period of time), the current limiters of the overcurrent protection circuit may be configured to “reset.” The current limiters may be configured to terminate the flow of current at the output120in response to the current flow at the output120again exceeding the threshold current for the threshold period of time (i.e., the current limiter is configured to terminate the flow of current at the output120in response to the threshold current level continuously exceeding the threshold period of time). In other embodiments, the threshold period of time is or includes a period of time that may be exceeded within one or more time windows. By way of example, a current limiter may be configured to terminate the flow of current at the output120in response to the current draw exceeding a threshold current level of 25 Amps for a threshold time period of 20 seconds within the previous 60 seconds. Such a current limiter may provide overcurrent protection despite momentary reductions in the current draw and/or a current draw profile that, in the aggregate, could result in damage to one or more components of the energy storage and power supply device10.

By way of example, the current flow at the output120may be 55 Amps during an initial startup period of the external device400. The 55 Amp current draw during the initial startup period may exceed the threshold current level of the first current limiter (e.g., 10 Amps, etc.), the second current limiter (e.g., 25 Amps, etc.), and the third current limiter (e.g., 50 Amps, etc.). Because the 55 Amp current draw exceeds the 50 Amp threshold current level of the third current limiter, the third current limiter is configured to terminate the flow of current to the output120in response to the initial startup period exceeding the 2 second threshold period of time associated with the third current limiter, according to one example. The third current limiter may thereby continue to permit the flow of current to the output120until the 50 Amp threshold current level is exceeded for 2 or more seconds.

In other embodiments, one or more of the current limiters has a threshold period of time equal to zero. In other words, when the threshold current level of the current limiter is reached or exceeded, the current limiter is configured to immediately terminate the current flow to and/or from the output120. One or more of the current limiters may thereby operate as a traditional hard stop point, terminating the flow of current at the output120if the current flow at the output120(e.g., the current draw by the external device400, etc.) exceeds the threshold current level even briefly.

According to various embodiments, at least one of the current limiter and the overcurrent protection circuit200includes a fuse. In other embodiments, the overcurrent protection circuit200includes operational amplifiers, amplifiers, resistors, and/or other electronic components. In still other embodiments, the overcurrent protection circuit200includes a fuse circuit. The fuse circuit may include one or more polymeric positive temperature coefficient devices (e.g., resettable fuses, polyfuses, polyswitches, etc.). The fuse circuit may include a switching circuit that selectively routes electrical energy to one of a number of fuse circuits where each of the fuse circuits includes a polymeric positive temperature coefficient device that is different from the other polymeric positive temperature coefficient devices. In this way, the overcurrent protection circuit200may adjust the current limiters to tailor the overcurrent protection circuit200for a target application.

According to the exemplary embodiment shown inFIG. 3, the energy storage and power supply device100includes a regulator, shown as regulator210. By way of example, the regulator210may include a switch. As shown inFIG. 3, a current flow may be provided from the energy storage unit140to the output120. In one embodiment, the regulator210is disposed along a current flow path between the energy storage unit140and the output120. By way of example, the regulator210may be configured to receive electrical energy from the energy storage unit140and selectively transmit electrical energy to the output120. The energy storage and power supply device100may include either or both of the overcurrent protection circuit200and the regulator210.

In one embodiment the processing circuit160(e.g., the overcurrent protection module184, etc.) is configured to engage the regulator210to selectively terminate the flow of current to the output120. In one embodiment, the energy storage and power supply device100(e.g., the processing circuit160, etc.) is configured to wait a period of time after terminating the current flow to the output120before again permitting the flow of current to the output120(e.g., by again engaging the regulator210, etc.). In other embodiments, the processing circuit160is configured to engage the overcurrent protection circuit200to selectively terminate the flow of current to the output120. The overcurrent protection module184may be configured to monitor the current flow at the output120(e.g., based on data provided by the output current sensor196, etc.) and provide signals such that the processing circuit160selectively terminates the flow of current to the output120. The processing circuit160(e.g., the overcurrent protection module184, etc.) may thereby be configured to provide software protection, software-based overcurrent protection, firmware current limiting control, etc.

According to an exemplary embodiment, the overcurrent protection module184includes one or more current set points. A threshold current level and a threshold period of time may be associated with each of the current set points. The overcurrent protection module184may be configured to terminate the current flow to the output120in response to the current flow at the output120(e.g., the current draw by the external device400, etc.) exceeding the threshold current level for a duration that reaches or exceeds the threshold period of time. In one embodiment, the overcurrent protection module184includes a timer module configured to monitor the duration that the current flow at the output has exceeded the one or more threshold current levels. The overcurrent protection module184may facilitate operating the energy storage and power supply device100according to a variable maximum current versus time function.

By way of example, the overcurrent protection module184may include a first current set point having a threshold current level of 10 Amperes (“Amps”), a second current set point having a threshold current level of 25 Amps, and a third current set point having a threshold current level of 50 Amps. The first current set point, having threshold current level of 10 Amps, may have a threshold period of time of 100 seconds. The second current set point, having a threshold current level of 25 Amps, may have a threshold period of time equal to 20 seconds. The third current set point, having a threshold current level of 50 Amps, may have a threshold period of time equal to 2 seconds. The overcurrent protection module184may thereby provide overcurrent protection at the output120according to a current protection curve or a current protection profile (e.g., defined by the series of steps or threshold currents and corresponding threshold periods of time, etc.). One exemplary current protection curve or current protection profile is provided below. In other embodiments, the overcurrent protection module184has more or fewer current set points and/or the current set points have different threshold current level and/or threshold period of time settings.

During use of the energy storage and power supply device100, the current flow at the output120(e.g., the current draw by the external device400, etc.) may vary. By way of example, the current flow at the output120may be 55 Amps during an initial startup period of the external device400. The 55 Amp current draw during the initial startup period may exceed the threshold current level of the first current set point (e.g., 10 Amps, etc.), the second current set point (e.g., 25 Amps, etc.), and the third current set point (e.g., 50 Amps, etc.). Because the 55 Amp current draw exceeds the 50 Amp threshold current level of the third current set point, the overcurrent protection module184and/or the processing circuit160may be configured to engage the regulator210to terminate the flow of current to the output120in response to the initial startup period exceeding the 2 second threshold period of time associated with the third current set point, according to one example. In other words, the processing circuit160may thereby continue to permit the flow of current to the output120until the 50 Amp threshold current level of the third current set point is exceeded for 2 or more seconds. The processing circuit160may be configured to also permit the flow of current to the output120in response to the 55 Amp current draw falling below the 50 Amp threshold current level of the third current set point within the 2 second threshold period of time of the third current set point.

While the processing circuit160may be configured to not interrupt the flow of current in response to the exemplary 55 Amp current draw falling below the 50 Amp threshold current level within 2 seconds, the processing circuit160may be configured to terminate the current flow in response to the current draw exceeding 25 Amps for a period of 10 seconds (i.e., in response to the current draw exceeding the threshold current level of the second set point for the threshold period of time for the second set point). By way of example, the processing circuit160may be configured to terminate the current flow to the output120in response to a current draw of 55 Amps for a period of 1 second and a current draw of 30 Amps for 9 seconds. In other words, the processing circuit160may be configured to begin elapsing the threshold periods of time for the various current set points simultaneously in response to the current draw exceeding the corresponding threshold current levels.

While the foregoing example describes an exemplary current draw during an initial startup period of time, the processing circuit160may be configured to terminate the flow of current to the output120at any point during use of the energy storage and power supply device100in response to a current draw exceeding any one of the threshold current levels for the threshold periods of time. In still other embodiments, the processing circuit160is otherwise configured to terminate the flow of current to the output120based on current draw and time (e.g., in response to an integral of a current draw versus time profile exceeding a threshold level, using an algorithm, etc.).

In response to the current flow at the output120initially exceeding the threshold current and thereafter falling below the threshold current level (falling below the threshold current level within the threshold period of time), the processing circuit may be configured to “reset” the timer module(s) measuring the elapsed times that the threshold current levels have been exceeded. The processing circuit160may be configured to terminate the flow of current at the output120in response to the current flow at the output120again exceeding the threshold current for the threshold period of time (i.e., the processing circuit160is configured to terminate the flow of current at the output120in response to the threshold current level continuously exceeding the threshold period of time). In other embodiments, the threshold period of time is or includes a period of time that may be exceeded within one or more time windows. By way of example, a processing circuit160may be configured to terminate the flow of current at the output120in response to the current draw exceeding a threshold current level of 25 Amps for a threshold time period of 20 seconds within the previous 60 seconds. The processing circuit160may thereby provide overcurrent protection despite momentary reductions in the current draw and/or a current draw profile that, in the aggregate, could result in damage to one or more components of the energy storage and power supply device10.

By way of example, the current flow at the output120may be 55 Amps during an initial startup period of the external device400. The 55 Amp current draw during the initial startup period may exceed the threshold current level of the first current set point (e.g., 10 Amps, etc.), the second current set point (e.g., 25 Amps, etc.), and the third current set point (e.g., 50 Amps, etc.). Because the 55 Amp current draw exceeds the 50 Amp threshold current level of the third current set point, the processing circuit160may terminate the flow of current to the output120in response to the initial startup period exceeding the 2 second threshold period of time associated with the third current set point, according to one example. The processing circuit160may thereby continue to permit the flow of current to the output120until the 50 Amp threshold current level is exceeded for 2 or more seconds.

In other embodiments, one or more of the current set points has a threshold period of time equal to zero. In other words, when the threshold current level of the current set point is reached or exceeded, the processing circuit160is configured to immediately terminate the current flow to and/or from the output120. The processing circuit160may thereby operate as a traditional hard stop point, terminating the flow of current at the output120if the current flow at the output120(e.g., the current draw by the external device400, etc.) exceeds the threshold current level even briefly.

In one embodiment, the processing circuit160and the overcurrent protection circuit200cooperate to provide overcurrent protection. According to various embodiments, the overcurrent protection circuit200and the overcurrent protection module184are configured to operate simultaneously. Similarly, in some embodiments, the overcurrent protection circuit200and the overcurrent protection module184may be configured to operate any time energy storage and power supply device100is in operation. By way of example, either or both of the processing circuit160and the overcurrent protection circuit200may terminate the flow of current to the output120. In other embodiments, the energy storage and power supply device100does not include the overcurrent protection circuit200, does not include the regulator210, and/or the processing circuit is not configured to selectively terminate the flow of current to the output120.

In these ways, the overcurrent protection circuit200and the overcurrent protection module184are configured to facilitate operation of an output interface of energy storage and power supply device100during surges in the current drawn at the output120. By combining several current limiters from the overcurrent protection circuit200, the energy storage and power supply device100may construct a current versus time function thereby facilitating effective operation of devices that do not draw a constant current (e.g., and may exceed traditional current limits but only for a brief time, etc.). In some embodiments, outputs of the energy storage and power supply device100(e.g., I/O ports48, etc.) may be separated into alternating current output interfaces having one current versus time function and direct current output interfaces having a second current versus time function (e.g., with different overcurrent protection circuits200and/or profiles utilized by the overcurrent protection module184, etc.).

In one embodiment, the energy storage and power supply device100includes one output120. In other embodiments, the energy storage and power supply device100includes a plurality of outputs120(e.g., a plurality of the I/O ports48, etc.). The energy storage and power supply device100may include different overcurrent protection circuits200and/or regulators210for the various outputs120. The overcurrent protection circuits200and/or regulators210may use and/or be controlled using different threshold current levels and/or different threshold periods of time that are tailored to each associated output120. The threshold current levels and/or the threshold periods of time may be different for different outputs120. In other embodiments, the overcurrent protection circuit200and/or the regulator210provides overcurrent protection to multiple outputs120. By way of example, the current flow monitored by the overcurrent protection circuit200and/or the processing circuit160may include an aggregate of the current flows provided to the various outputs120. In still other embodiments, sets of overcurrent protection circuits200and/or regulators210provide overcurrent protection to various groups of outputs (e.g., each group including a number of the I/O ports48, etc.). For example, one group of overcurrent protection circuits200and/or regulators210may be associated with outputs that are configured for use in high-current applications (e.g., for starting an air-conditioning unit, etc.), and a second group of overcurrent protection circuits200and/or regulators210may be associated with outputs that are configured for use in low-current applications. The groups of overcurrent protection circuits200and/or regulators210may use and/or be controlled using different threshold current levels and/or different threshold periods of time that are tailored to the particular group of outputs120(e.g., set points particularly tailored to high-current applications, set points particularly tailored to low-current applications, etc.).

According to an exemplary embodiment, the display module182is configured to interpret the input current data (e.g., acquired and/or calculated based on data provided by the input current sensor192, etc.) and/or the input voltage data (e.g., acquired and/or calculated based on data provided by the input voltage sensor194, etc.) at the input interface110of the energy storage and power supply device100. The display module182may be configured to calculate the electrical power provided by the power supply device300. In one embodiment, the display module182is configured to calculate the electrical power provided by the power supply device300by multiplying the input current with the input voltage (e.g., acquired and/or calculated based on data provided by the input current sensor192, the input voltage sensor194, etc.). The display module182may provide the electrical power data for presentation on a display162. In other embodiments, the display module182provides one or more of the threshold current levels and/or the threshold current periods for presentation on the display162.

Referring now toFIG. 4, a method500for controlling current flow out of an output of an energy storage and power supply device is shown, according to an exemplary embodiment. At step502, an energy storage and power supply device (e.g., the energy storage and power supply device10, the energy storage and power supply device100, etc.) including an energy storage unit (e.g., the energy storage unit30, the energy storage unit140, etc.), an output (e.g., the output120, etc.) coupled to the energy storage unit, and at least one of (i) an overcurrent protection circuit (e.g., the overcurrent protection circuit200, etc.) positioned along a current flow path between the energy storage unit and the output, (ii) a processing circuit (e.g., the processing circuit160, etc.), and (iii) a regulator (e.g., the regulator210, etc.) positioned along the current flow path between the energy storage unit and the output is provided.

At step504, a current flow drawn from the energy storage unit by a load device (e.g., the external device400, etc.) connected to the output is monitored by at least one of the overcurrent protection circuit and the processing circuit. At step506, the current flow being provided to the output is terminated with the at least one of (i) the overcurrent protection circuit, (ii) the processing circuit, and (iii) the regulator in response to the current flow exceeding a threshold current for longer than a threshold period of time.

In some embodiments, the energy storage and power supply device only includes the overcurrent protection circuit. The overcurrent protection circuit may include one or more current limiters containing various hardware components (e.g., fuses, operational amplifiers, amplifiers, resistors, other electronic components, etc.) that provide a current protection curve or current protection profile (i.e., hardware-based overcurrent protection). In some embodiments, the energy storage and power supply device only includes the processing circuit and one of the overcurrent protection circuit and the regulator. The processing circuit may provide a signal to the overcurrent protection circuit or the regulator to terminate the current flow according to a current protection curve or current protection profile (various current and time based thresholds) (i.e., software-based overcurrent protection). In some embodiments, the energy storage and power supply device include the overcurrent protection circuit, the processing circuit, and the regulator (i.e., both hardware-based and software-based overcurrent protection).

It should be noted that the terms “exemplary” and “example” as used herein to describe various embodiments is intended to indicate that such embodiments are possible examples, representations, and/or illustrations of possible embodiments (and such term is not intended to connote that such embodiments are necessarily extraordinary or superlative examples).