System and method for providing a fluid-affected fuse

Abstract

The present disclosure relates to systems and methods for providing a fluid-affected fuse. A fluid-affected fuse includes a structural housing, a pair of electrical terminals, one or more fuse elements, and a fluid arranged in an internal volume of the structure. The structure provides rigidity to the fuse. The terminals are coupled to the structural housing and configured to be coupled to a power circuit of a battery circuit. One or more fuse elements are electrically connected in series to a pair of electrical terminals and are arranged in the internal volume. The fluid is configured to affect the temperature of the fuse element. A fluid-filled fuse is filled with a fluid, optionally sealed, and operates with the increased thermal capacity of the fluid to affect the temperature of the fuse. A fluid-cooled fuse is filled with a fluid, undergoes a fluid flow, thereby allowing control of the fuse temperature. A control system controls the fluid flow and fuse operation.

Description

Technical Field

[0001] The present disclosure relates to fluid-affected fuses, and more particularly, to systems for controlling the operation of fuses based on fluids. Summary of the invention

[0002] In some embodiments, the present disclosure relates to a device comprising a structural housing, a pair of electrical terminals, a fuse element, and a fluid. The structural housing comprises an internal volume. The electrical terminals are coupled to the structural housing and configured to be coupled to a power circuit of a battery circuit. The fuse element is electrically connected in series with the electrical terminals and is at least partially arranged in the internal volume. The fluid is configured to affect the temperature of the fuse element. The device is also referred to as a fluid-affected fuse.

[0003] In some embodiments, the device comprises a port disposed in the structural housing and configured to allow the fluid to be provided to the interior volume.

[0004] In some embodiments, the device includes a first port disposed in the structural housing, the first port configured to allow the fluid to be provided to the internal volume, and a second port disposed in the structural housing, the second port configured to allow the fluid to be removed from the internal volume. For example, in some embodiments, the first port and the second port are configured to provide an inlet and an outlet to the internal volume.

[0005] In some embodiments, the device includes a sensor configured to sense at least one characteristic of the device. In some such embodiments, the sensor is disposed in the structural housing. In some embodiments, the at least one characteristic includes a temperature of the device, and the sensor is configured to sense the temperature. For example, the temperature is the temperature of the fluid, the temperature of the structural housing, the temperature of the fluid flow, the temperature of an electrical terminal or busbar, or the temperature of another component indicating a fuse.

[0006] In some embodiments, the fluid comprises at least one of water, oil, ethylene glycol or a combination thereof. For example, in some embodiments, the fluid comprises K-grade transformer oil, mineral oil, oil containing synthetic esters, oil containing natural esters or a coolant.

[0007] In some embodiments, the present disclosure relates to a system comprising a power system, a fuse, and a control circuit. The power system comprises at least one busbar. The fuse is configured to provide circuit protection and comprises a pair of terminals, a structural housing, a fuse element, and a fluid. The pair of terminals is electrically coupled to the at least one busbar. The structural housing comprises an internal volume. The fuse element is electrically coupled between the pair of terminals and is arranged in the internal volume. The fuse element is configured to disconnect the terminals under predetermined conditions. The fluid is arranged in the internal volume, surrounding or otherwise adjacent to the fuse element. The control circuit is configured to monitor at least one characteristic of the fuse during operation.

[0008] In some embodiments, the system includes a sensor configured to sense at least one characteristic of the fuse. The sensor is communicatively coupled to the control circuit. In some embodiments, the at least one characteristic includes a temperature of a fluid disposed in the internal volume.

[0009] In some embodiments, the system includes a fluid management system configured to circulate a fluid flow through the interior volume of the structural housing. The fluid in the interior volume is supplied by the fluid flow. For example, in some embodiments, the fuse includes a first port and a second port arranged in the structural housing, and the fluid flow enters the interior volume via the first port and leaves the interior volume via the second port.

[0010] In some embodiments, the fluid management system includes a pump, a fluid conduit, and accessories configured to manage the fluid flow. In some embodiments, the control circuit is coupled to the fluid management system and is further configured to provide a control signal to the fluid management system to control the fluid flow. In some embodiments, the control circuit is further configured to provide a control signal to the fluid management system to control the temperature of the fuse.

[0011] In some embodiments, the present disclosure relates to a method for managing a fuse affected by a fluid. The method includes monitoring one or more sensor signals indicating operation of the fuse, applying current to one or more busbars of a battery system, and generating a control signal for controlling a fluid flow, the fluid flow being configured to flow through an internal volume of the fuse. The fuse is electrically coupled to the one or more busbars so that current flows through the fuse.

[0012] In some embodiments, monitoring the one or more sensor signals includes monitoring a temperature sensor signal of a temperature sensor configured to sense a temperature of the fluid flow. In some such embodiments, generating the control signal includes generating the control signal to control a temperature of the fuse.

[0013] In some embodiments, the method includes determining that a fault has occurred based on the one or more sensor signals. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present disclosure according to one or more different embodiments is described in detail with reference to the following drawings. The drawings are provided for illustrative purposes only and depict only typical or exemplary embodiments. These drawings are provided to facilitate understanding of the concepts disclosed herein and should not be construed as limiting the breadth, scope or applicability of these concepts. It should be noted that for clarity and ease of illustration, these drawings are not necessarily drawn to scale.

[0015] Figure 1 shows a side view and a cross-sectional side view of an illustrative fluid filled fuse according to some embodiments of the present disclosure;

[0016] Figure 2 shows a cross-sectional side view of an illustrative fluid cooled fuse and pump system according to some embodiments of the present disclosure;

[0017] Figure 3 shows a block diagram of an illustrative system for managing fuses according to some embodiments of the present disclosure;

[0018] Figure 4 A flowchart showing an illustrative process for managing a fluid-affected fuse according to some embodiments of the present disclosure; and

[0019] Figure 5 An illustrative graph showing fuse blowing time as a function of fuse current according to some embodiments of the present disclosure is shown. DETAILED DESCRIPTION

[0020] The present disclosure relates to fuses with fluid-based properties. In some embodiments, the fuse is filled with a fluid and then sealed. In some embodiments, the fuse is fluid-cooled (e.g., based on the flow rate of the fluid). For illustration, a fluid-filled fuse and a fluid-cooled fuse may be implemented with or without a conductive fluid. Since the fuse element (e.g., carrying current) may operate at high voltages, an electrical insulator may be used to prevent the fluid from being energized. Using a fluid-filled fuse or a fluid-cooled fuse may allow for a more compact design (e.g., which in turn may increase the energy density of a related battery pack), support high performance targets (e.g., high current) while maintaining system durability, or both.

[0021] Figure 1Shown are side views and cross-sectional side views of an illustrative fluid-filled fuse 100 according to some embodiments of the present disclosure. As shown, fuse 100 includes structure 155, terminals 171 and 172, port 173, sensor 174, elements 161 and 162, and fluid 151. As shown, structure 155 includes side walls and ends, which serve as a package for fuse 100. For example, structure 155 can provide electrical insulation, structural rigidity, passage of fluid 151, accommodation of fluid 151, protection of elements 161 and 162, any other suitable function, or any combination thereof. Terminals 171 and 172 are configured to be electrically coupled to a circuit. In some embodiments, terminals 171 and 172 are electrically insulated from structure 155 so that all currents between terminals 171 and 172 pass through and flow along elements 161 and 162. For example, fuse 100 can be included in line (in series) with a busbar so that current flowing through the busbar (e.g., between terminals 171 and 172) passes through fuse 100. For illustration, elements 161 and 162 arranged electrically in parallel can conduct current between terminals 171 and 172. In some embodiments, elements 161 and 162 can be similar (e.g., and included in integer multiples according to the rated current of fuse 100). In some embodiments, a single element is included in a fluid-filled fuse, where the element is sized for a predetermined current capacity.

[0022] Fluid 151 is arranged and contained in the internal cavity of structure 155. For illustration, the internal space of structure 155 can be filled with fluid 151 via port 173. After filling, port 173 can be closed or otherwise sealed to prevent leakage or overflow. In some embodiments, port 173 can be used as a vent. In some embodiments, fluid 151 can include enough thermal conductivity to transfer heat that can be generated by ohmic loss (e.g., based on resistivity) from elements 161 and 162. In some embodiments, fluid 151 can be non-conductive (e.g., oil, non-polar liquid, non-ionized liquid). In some embodiments, structure 155, elements 161 and 162, terminals 171 and 172, or a combination thereof can include a dielectric coating, layer, or insert that can electrically insulate fluid 151 from solid-state components (e.g., terminals, elements, structures). In some embodiments, port 173 can be opened or otherwise approached to inspect, sample, or otherwise characterize fluid 151, elements 161 and 162, or a combination thereof. For example, port 173 may include a removable plug that can be removed to inspect, characterize, and / or maintain fluid 151 (eg, check color, measure viscosity, analyze composition, refill fluid 151, drain fluid 151).

[0023] To illustrate, the additional thermal mass of fluid 151 relative to the rest of fuse 100 (e.g., defined by the heat capacity of fluid 151) can aid in temperature control of fuse 100. For example, the thermal mass of fluid 151 can mitigate temperature increases of elements 161 and 162 by increasing the effective heat capacity of the fuse. In another example, fuse 100 can cause elements 161 and 162 to exhibit relatively smaller temperature increases than if fluid 151 were not present. In some embodiments, the increased thermal mass provided by fluid 151 can reduce the severity of thermal shock (e.g., the magnitude of temperature changes). In some embodiments, the presence of fluid 151 can affect the temporal response of fuse 100. For example, the presence of fluid 151 can act as a filter to prevent current spikes (e.g., by preventing temperature increases) within a suitable time scale.

[0024] As shown, fuse 100 includes sensor 174. Sensor 174 is configured to sense one or more properties of fuse 100 or changes therein. For example, in some embodiments, sensor 174 includes a temperature sensor (e.g., a thermocouple, a thermopile, a thermistor, a resistance temperature detector (RTD), any other suitable temperature sensor, or any combination thereof, for sensing the temperature of fluid 151, structure 155, or both. In another example, sensor 174 can include a pressure sensor, a voltage sensor, a sensor configured to detect a property of fluid 151 (e.g., an optical, thermophysical, electrical, chemical, or electrochemical property), any other suitable type of sensor, or any combination thereof. In some embodiments, sensor 174 can be coupled to a control system or a sensor interface thereof, and a signal from sensor 174 can be used as an indicator to monitor the state of fuse 100 or its elements 161 and 162. In some embodiments, based on the characteristics of fluid 151, the overall package size of the fuse can be reduced by including fluid 151. In some embodiments, sensor 174 is installed in port 173 (e.g., after filling with fluid 151). For example, sensor 174 can be removably or permanently installed in port 173.

[0025] Fluid 151 can have any suitable properties, such as viscosity, density, conductivity (e.g., electrical and / or thermal), flash point, boiling point, freezing point, heat capacity, corrosion resistance, any other suitable property, or any combination thereof. For example, the freezing temperature of fluid 151 can be selected to prevent phase change of fluid 151 (e.g., particularly for fluid-filled fuses in which the fluid is not circulated). In another example, fluid 151 can have sufficient electrical insulation to prevent electrical shorting within fuse 100 (e.g., no dielectric insert is required to separate elements 161 and 162 from structure 155). Fluid 151 can include, for example, water (W), ethylene glycol (EG), a WEG mixture, a low viscosity oil (e.g., silicone oil, mineral oil, synthetic oil, synthetic ester, natural ester), a high viscosity K-grade oil (e.g., silicone oil, mineral oil, synthetic oil, synthetic ester, natural ester), a phase-changing fluorinated synthetic fluid (e.g., Novec), any other suitable fluid, any suitable additive (e.g., a corrosion inhibitor), or any suitable combination thereof.

[0026] Figure 2 A cross-sectional side view of an illustrative fluid-cooled fuse 210 and a pump system 250 according to some embodiments of the present disclosure is shown. As shown, the system 200 includes a fluid-cooled fuse 210, a pump system 250, any suitable fluid conduit for providing a fluid (e.g., fluid 251) and returning the fluid, any suitable sensor interface (e.g., for coupling to a sensor 274), any other suitable component (not shown), or any combination thereof. In some embodiments, the fuse 210 may be similar to the fuse 100 except that more than one port may be included. For example, the fuse 210 may be included in line (in series) with the busbar so that the current flowing through the busbar (e.g., between terminals 271 and 272) passes through the fuse 210. For illustration, the elements 261 and 262 of the parallel electrical arrangement may conduct current between the terminals 271 and 272. In some embodiments, the elements 261 and 262 may be similar (e.g., and included in integer multiples according to the rated current of the fuse 210). In some embodiments, a single element is included in a fluid-cooled fuse, wherein the element is sized for a predetermined current capacity. Although shown as having two elements, according to the present disclosure, a fluid-filled fuse or a fluid-cooled fuse may include any suitable number of elements (e.g., one, two, or more).

[0027] As shown, fuse 210 includes structure 255, terminals 271 and 272, ports 273 and 283, sensor 274, elements 261 and 262, and fluid 251 (e.g., included in the interior volume of structure 255). Ports 273 and 283 are configured to allow fluid to flow into and out of the interior volume of structure 255. For example, pump system 250 is configured to pump fluid 251 into and out of fuse 210 via a suitable conduit (e.g., a tube, a pipe, a hose, a fitting, a plenum, a manifold, or a combination thereof). Pump system 250 may include, for example, a centrifugal pump, a positive displacement pump (e.g., a piston pump), a vacuum system, an airbag system, any other suitable system for moving a fluid, or any combination thereof. In some embodiments, pump system 250 includes a control circuit having a sensor interface that is configured to receive a sensor signal from sensor 274. For illustration, sensor 274 may be similar to Figure 1 Sensor 274. To further illustrate, sensor 274 can include a sensor configured to sense temperature (e.g., temperature of fluid 251 or any other suitable portion of fuse 210), pressure (e.g., pressure of fluid 251 in the interior volume of structure 255), pressure drop (e.g., pressure drop across ports 273 and 283 or any other suitable pressure differential), any other suitable property, or any combination thereof. In some embodiments, sensor 274 can be integrated into one or both of ports 273 and 283. In some embodiments, sensor 274 can be disposed in a fluid conduit rather than being integrated or inserted into structure 255.

[0028] Fluid 251 can have any suitable properties, such as viscosity, density, conductivity (e.g., electrical and / or thermal), flash point, boiling point, heat capacity, any other suitable property, or any combination thereof. Fluid 251 can include, for example, water (W), ethylene glycol (EG), a WEG mixture, a low viscosity oil (e.g., silicone oil, mineral oil, synthetic oil, synthetic ester, natural ester), a high viscosity K-grade oil (e.g., silicone oil, mineral oil, synthetic oil, synthetic ester, natural ester), a phase change fluorinated synthetic fluid (e.g., Novec), any other suitable fluid, or any combination thereof.

[0029] Figure 3A block diagram of an illustrative system 300 for managing fuses 334 according to some embodiments of the present disclosure is shown. As shown, system 300 includes a power source 302, a control circuit 310, a fluid system 320, and an electrical system 330. As shown, electrical system 330 includes a battery system 331, wherein fuse 334 can be electrically coupled to a busbar of battery system 331. As shown, fluid system 320 can optionally be included to manage fluid flow into and out of fuse 334. For example, in some embodiments, wherein fuse 334 includes a fluid-filled fuse, fluid system 320 need not be included (e.g., or can be included to fill the fluid-filled fuse but not used during operation). For illustration, system 300 can be part of an electric vehicle, wherein battery system 331 is configured to provide power to a powertrain of the electric vehicle. For further illustration, any or all of fuses 334 can include a fuse similar to Figure 1 A fuse of 100 or Figure 2 The fuse 210 is a fuse.

[0030] As shown, the control circuit 310 includes a processor 312, a sensor interface 313, an input / output 314 (hereinafter referred to as I / O 314), a communication hardware 315 (hereinafter referred to as COMM 315), and a memory 316. The control circuit 310 may include hardware, software, or both hardware and software implemented on one or more modules, and the one or more modules are configured to provide control, monitoring, or both control and monitoring of one or more fuses 334. In some embodiments, the processor 312 includes one or more microprocessors, microcontrollers, digital signal processors, programmable logic devices, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), or any suitable combination thereof. In some embodiments, the processor 312 is distributed on more than one processor or processing unit. In some embodiments, the control circuit 310 executes instructions stored in the memory 316 to manage one or more fuses 334. In some embodiments, the memory 316 is an electronic storage device that is part of the control circuit 310. For example, the memory 316 can be configured to store electronic data, computer instructions, applications, firmware, or any other suitable information. In some embodiments, memory 316 includes random access memory, read-only memory, a hard drive, an optical drive, a solid-state device, or any other suitable memory storage device, or any combination thereof. For example, the memory may be used to launch a boot routine.

[0031] In some embodiments, the control circuit 310 is powered by a power source 302. In some embodiments, the power source 302 includes an automobile battery (e.g., a 12V lead-acid battery), a DC-DC converter, an AC power source (e.g., generated by appropriately inverting a DC power source), any other power source, any corresponding components (e.g., terminals, switches, fuses, and cables), or any combination thereof. In some embodiments, the power source 302 provides power to the sensor 317, the fluid system 320, the electrical system 330, any other suitable system or component, or any combination thereof. In some embodiments, the control circuit 310, the fluid system 320, or both may be powered by a battery system 331.

[0032] The sensor interface 313 is configured to provide power or other excitation to the sensor 317, receive a sensor signal from the sensor 317, condition the sensor signal (e.g., filter, amplify, saturate, convert, or perform other conditioning), modulate the sensor signal, digitize the sensor signal (e.g., analog-to-digital converter), or a combination thereof. In some embodiments, the sensor interface 313 is configured to sample and digitize the sensor signal from the sensor 317. In some embodiments, the sensor 317 includes one or more temperature sensors (e.g., thermistors, thermocouples, thermopiles, resistance temperature detectors, and infrared optical detectors), pressure sensors (e.g., strain or piezoelectric transducers), current sensors (e.g., current loops or other transformers, precision resistors), voltage sensors, optical sensors (e.g., for photon properties or clarity), any other suitable sensor, or any combination thereof. For example, the sensor 317 may include a current sensor or a voltage sensor configured to sense the operation of the fuse 334 to determine the operation of the fuse 334. Sensor 317 can be integrated as part of fuse 334, arranged adjacent to fuse 334, arranged in a conduit of fluid system 320, in any other suitable arrangement, or any combination thereof. In some embodiments, control circuit 310 can determine a property value (e.g., a temperature value), whether there is a fluid leak, a flow rate, a pressure, any other suitable property, or any combination thereof based on one or more sensor signals.

[0033] I / O 314 and Comm 315 are configured to send and receive signals. In some embodiments, I / O 314 is configured to receive sensor signals (e.g., sensor interface 313 can be integrated as part of I / O 314), send and receive digital signals, generate or measure current (e.g., 4-20 mA signal), generate or measure voltage (e.g., provide or measure analog voltage), provide binary signals (e.g., to control relays, switches, contactors, or transistors), provide power (e.g., DC bus for control signals), send or receive any other suitable signal, or any combination thereof. In some embodiments, Comm 315 includes a wireless communication interface (e.g., WiFi, Bluetooth, NFC, 4-G), a wired interface (e.g., Ethernet with an RJ-45 connector), an optical interface (e.g., a fiber optic interface), any other suitable interface, or any combination thereof for communicating with other systems or devices.

[0034] Fluid system 320 is configured to manage the state of fluid in a fluid-filled fuse, a fluid-cooled fuse, or both of fuse 334. Fluid system 320 may include a pump (e.g., a piston pump, a centrifugal pump, a vane pump, any other suitable pump, a motor, a motor drive, a controller), a fluid regulating system (e.g., a pressure regulator, a valve, a throttle, a degassing system, a tank, a manifold, a fitting), a communication interface (e.g., for communicating with control circuit 310), any other suitable component or system, or any combination thereof. Fluid system 320 may be configured to fill fuse 334 with a fluid, provide a fluid flow to fuse 334, control a fluid flow to fuse 334, monitor a fluid flow to fuse 334, or a combination thereof. In some embodiments, fluid system 320 is used to fill a fuse and then is separated from system 300 during operation.

[0035] To illustrate, the system 300 can allow for the ability to change the flow rate of a fluid (e.g., via the fluid system 320) to a fuse (e.g., one or more of the fuses 334) to match the power demand of the electrical system 330. For example, the control circuit 310 can be configured to receive a sensor signal from the sensor 317 indicating the current flowing through the fuse 334. Thus, the fluid flow can be increased to remove more heat from the fuse 334 (e.g., or the fluid flow can be reduced to reduce heat removal). In some embodiments, one or more valves are used at the inlet, outlet, or both of the fuse 334. For example, in some such embodiments, any or all of the fuses 334 can be drained of fluid to affect when the fuse fails (e.g., when the fuse blows under current load). To illustrate, in the event of a short circuit being detected, the system 300 can reduce the cooling load of the fuse 334, thereby causing the fuse to fail rather than the short circuit continuing (e.g., which may cause damage to other components).

[0036] As shown, the electrical system 330 includes a battery system 331, which includes a plurality of battery cells connected together by one or more busbars. The fuse 334 is arranged in line (e.g., in series) with the one or more busbars and is configured to provide circuit protection to prevent large currents (e.g., to prevent short circuits or high loads that may cause overheating and failure). In some embodiments, the electrical system 330 includes power electronics, electric motors, motor drives, any other suitable components, or any combination thereof that can trade power with the battery system 331. For example, the control circuit 310 can generate a control signal and transmit the control signal to the electrical system 330 via the I / O 314 to control one or more motor drives or IGBTs that control the power to one or more electric motors (e.g., of an electric vehicle powertrain).

[0037] Figure 4 FIG. 4 is a flow chart showing an illustrative process 400 for managing a fuse affected by a fluid according to some embodiments of the present disclosure. In an illustrative example, the process 400 may be performed by Figure 3 The system 300 or any portion thereof is implemented.

[0038] Step 402 includes the system monitoring one or more sensor signals indicative of fuse operation. In some embodiments, the system monitors one or more sensors integrated into one or more fuses, one or more sensors installed in a fluid conduit coupled to one or more fuses, or a combination thereof. The system may monitor the one or more sensor signals, for example, continuously, at a predetermined frequency, in response to a query or event (e.g., in response to a message from a controller, a value of a property, a state of a system), at a predetermined time, or any combination thereof. In some embodiments, the system determines a metric (e.g., rated load, health indicator), a property value (e.g., temperature, voltage, current, pressure), any other suitable value, or any combination thereof to monitor fuse operation or fuse state. In some embodiments, the system stores (e.g., in a memory), filters (e.g., averaged, low-pass filtered, high-pass filtered, notch filtered, band-pass filtered, or a combination thereof), recalls (e.g., from a memory), or otherwise manages the value or metric of one or more sensor signals. In some embodiments, the sensor signal is used to determine or estimate the property value (e.g., the sensor signal can be used as a proxy). For example, the fluid temperature can be used to determine or estimate the temperature of the fuse element (e.g., using any suitable function mapping, model, or algorithm).

[0039] Step 404 includes the system applying a current to one or more fuses of the battery system. In some embodiments, the system manages the power supply (e.g., Figure 3The system may provide a control signal to the power electronics system to control the current in one or more buses, and thus control the current in one or more fuses. For example, the system may apply a current in response to a load.

[0040] Step 406 includes the system managing the fluid of one or more fuses. In some embodiments, the system includes a device for controlling one or more fuses (e.g., Figure 3 In some embodiments, the system controls the flow rate (e.g., by controlling a pump, valve, pressure, or other aspect of the fluid), the temperature of the fluid, the pressure of the fluid, the temperature of the fuse element or fuse body (e.g., a structural support), any other suitable characteristic of the operation of the fuse, or any combination thereof. In some embodiments, process 400 need not include step 406. For example, the system may include a fluid-filled fuse that, in some embodiments, does not require management during operation.

[0041] Step 408 includes the system identifying one or more operating states of one or more fuses, fluids, or both. In some embodiments, the system is configured to determine the operating state using as input one or more sensor signals, one or more metrics determined based on the one or more sensor signals, any other suitable information, or any combination thereof. Any suitable operating state may be identified, including, for example, normal operation (e.g., state 410), a fault condition (e.g., state 412), active control (e.g., state 414), generating a flag or warning (e.g., state 416), any other suitable state or mode, or any combination thereof.

[0042] In some embodiments, the system can retrieve information from a memory, database, or other suitable reference while monitoring one or more sensor signals, applying current to one or more fuses, managing fluids of one or more fuses, or a combination thereof. For example, with reference to a fluid filling fuse, the system can, but need not actively control the operation, but can monitor one or more sensor signals (or a metric derived therefrom) for comparison with a reference database. The reference database can include specified ranges, property values, algorithms for determining operating states based on one or more inputs (e.g., property values, sensor signals, metrics, messages / warnings, flag values), function mappings (e.g., in any suitable variable dimension), any other suitable information or relationship, or any combination thereof. For example, the reference database can include temperature limits, current limits, time limits, flow rate thresholds, current-temperature mappings, current-time mappings, time-temperature mappings, current-time-temperature mappings, fuse details (e.g., type of fuse, slow or fast blow characteristics, cycle life, usage history), any other suitable information, or any combination thereof.

[0043] In an illustrative example, the system may determine at step 408 that the fuse is operating normally or otherwise operating within an acceptable operating range based on one or more sensor signals of step 402, and thus identify state 410, as shown. Normal operation may include controlling power electronics to allow current (e.g., via busbars and any other circuits) to flow through the fuse, monitoring or maintaining the fluid condition (e.g., temperature, flow rate, heat transfer rate) of the fuse, any other suitable function, or any combination thereof. In some embodiments, normal operation may include the system actively controlling the operation of the fuse (e.g., state 414). For example, the system may adjust the flow rate, provide feedback control of the temperature (e.g., the temperature of the fuse or the temperature of the fluid), monitor one or more sensor signals, generate one or more control signals, or any combination thereof.

[0044] In an illustrative example, the system can determine that a fault has occurred based on one or more sensor signals of step 402 at step 408, and thus identify state 412, as shown. Faults can include electrical short circuits, fluid leakage of fuses, overheating of fuses, capacity reduction or change of fuses, any other suitable conditions or any combination thereof. In response to fault conditions, the system can stop the current through the fuse, reduce the current, change the fluid flow rate, generate a warning message, shut down the electrical system, disconnect the power supply (e.g., battery system), any other suitable function or any combination thereof. In some embodiments, the fuse may (e.g., due to overheating) undergo an irreversible process. For example, if the fuse is subjected to high current and related heating, the current capacity or fault schedule may change, so that the behavior of the fuse after the irreversible process is different from the behavior before the process (e.g., similar to plastic deformation or other irreversible phenomena in solids).

[0045] In an illustrative example, the system may generate a flag, warning, or other indicator based on the one or more sensor signals of step 402 at step 416. The flag may include, for example, a value stored in a memory indicating an operating state or a fault condition. In some embodiments, the system may generate a message, warning, or other indicator and transmit the indicator to one or more other systems (e.g., a shutdown system, a watchdog, a user interface, a central controller). The indicator may include an analog signal, a digital signal (e.g., a binary value), a message (e.g., using a suitable communication protocol), a graphical indicator generated on a display screen, any other suitable type of indicator, or any combination thereof.

[0046] Figure 5An illustrative graph 500 of fuse blowing time as a function of fuse current according to some embodiments of the present disclosure is shown. The abscissa of graph 500 corresponds to current (e.g., in amperes or any other suitable units), and the ordinate of graph 500 corresponds to time (in seconds). Trace 501 corresponds to one or more loads (e.g., controlled by an operating range of a powertrain component, an inverter, an auxiliary system, or a combination thereof), trace 502 corresponds to an illustrative fluid-affected fuse, and trace 503 corresponds to the total capacity of other protection components (e.g., fuses of a current collector of a battery system, contactors). In some embodiments, the fuse is designed to operate in a window arranged between traces 501 and 503. For example, a fuse may exhibit a time-current behavior that varies over time due to cyclic use (e.g., from an irreversible process or degradation), and is therefore expected to operate within a certain region of graph 500. This area can be selected and / or designed to fall between traces 501 and 503 to ensure that the load can operate uninterruptedly and other protection components do not fail prematurely (e.g., battery cell fuses) or otherwise become unactivated (e.g., contactors, which may be damaged by repeated overcurrent).

[0047] With respect to trace 503, a fuse may be disposed between each battery cell and a current collector that electrically couples a subset of the battery cells in parallel and in series with other subsets of the battery cells. To illustrate, the fuse between the battery cell and the current collector may include a separate fuse connection (e.g., a filament, a necked metal sheet) configured to disconnect each battery cell individually in the event of a battery cell overcurrent or a local event (e.g., a thermal event, an electrical short circuit of one or more battery cells). In another example, there may be several traces corresponding to the protection component. In some embodiments, the failure characteristics of the fluid-affected fuse include failing before the fuse of the current collector / battery cell at a given bus current, allowing the powertrain current to reach a maximum value without premature failure of the fluid-affected fuse, or a combination thereof. For example, normal operation may include controlling the current flowing in the powertrain component. The powertrain component may have a longer operating life at a lower current (e.g., a current lower than that indicated by line 510), and a shorter operating life at a higher current (e.g., where the operating life decreases with increasing current). For example, a powertrain component may be operated at a high current or "peak" current for relatively short durations, and may be operated continuously at a lower current (e.g., for an effectively infinite lifetime or otherwise for a time scale much greater than indicated on graph 500). To illustrate, a fluid-affected fuse may be configured to allow a powertrain component to draw a greater current without prematurely failing the fluid-affected fuse.

[0048] Furthermore, since the fluid-affected fuses may be arranged in series with the busbar and thus there may be relatively few fluid-affected fuses (e.g., corresponding to trace 503) compared to the large number of fusible connections of the current collector, failure of the fluid-affected fuses may be easier to correct. To illustrate, replacing the fluid-affected fuses of a busbar may be less intensive than replacing the large number of fusible connections of a current collector coupled to multiple battery cells, and thus the fluid-affected fuses may be designed to fail at relatively low currents compared to the currents that may cause the fusible connections to fail.

[0049] Line 511 corresponds roughly to a time threshold for which the current on a larger time scale may be affected by the fluid in the fuse. For example, at a time scale above line 511 (e.g., a longer time), the heat generated in the fuse may be transferred by the fluid to affect the operation of the fuse. In another example, at a time scale below line 511 (e.g., a shorter time), the heat generated in the fuse may not be effectively transferred by the fluid, so the effect of the fluid on the operation of the fuse may be relatively small. To illustrate, under conditions below line 511, the thermal mass of the fluid may be relatively less important to the operation of the fuse (e.g., the heat transfer from the fuse element may be limited by the surface area). In some embodiments, the benefits of the fuse affected by the fluid are manifested in a time scale between 1 second and 10 seconds. The fuse affected by the fluid of the present disclosure can benefit from the increased thermal mass of the fluid to mitigate temperature changes (e.g., this can improve durability), while still allowing for a rapid response to large current events occurring in a short period of time. Since the time scale of heat transfer in some cases (eg, at high currents) may be much longer than the opening time of the fuse, the presence of the fluid does not significantly hinder the ability of the fuse to respond to these events.

[0050] The foregoing is merely an illustration of the principles of the present disclosure, and various modifications may be made by those skilled in the art without departing from the scope of the present disclosure. The above embodiments are presented for the purpose of illustration rather than limitation. The present disclosure may also take many forms other than those explicitly described herein. Therefore, it should be emphasized that the present disclosure is not limited to the methods, systems, and devices explicitly disclosed, but is intended to include variations and modifications of the present invention within the spirit of the following claims.

Claims

1. A fuse device, comprising: a structural shell including an interior volume; a pair of electrical terminals coupled to the structural housing and configured to be coupled to an electrical power system; a fuse element electrically connected in series to the pair of electrical terminals and disposed at least partially within the interior volume; a fluid disposed in the interior volume and configured to affect a temperature of the fuse element; a port disposed in the structural housing to be in fluid communication with the interior volume and configured to provide fluid to the interior volume; an additional port disposed in the structural housing and configured to remove the fluid from the interior volume; as well as a sensor for providing a sensor signal indicative of an operating state of the fuse device, Wherein, if the operating condition indicates an electrical short circuit, the fluid is controlled to be discharged from the device to cause a fuse to fail. 2 . The device of claim 1 , wherein the sensor is configured to sense at least one characteristic of the device.

3. The device of claim 2, wherein the at least one characteristic comprises a temperature of the device, and wherein the sensor is configured to sense the temperature.

4. The apparatus of claim 2, wherein the at least one characteristic comprises at least one of a temperature of the fluid, a pressure of the fluid, or a composition of the fluid.

5. The device of claim 1, wherein the fluid comprises at least one of water, oil, ethylene glycol, or a combination thereof.

6. The device of claim 1, wherein the fluid is substantially electrically insulating.

7. A system for managing a fuse, comprising: An electric power system including at least one bus; A fuse configured to provide circuit protection, the fuse comprising: a pair of terminals electrically coupled to the at least one bus bar, A structural shell comprising an internal volume, a fuse element electrically coupled between the pair of terminals and disposed in the interior volume, wherein the fuse element is configured to disconnect the terminals under a predetermined condition, and a fluid disposed in the interior volume and configured to affect a temperature of the fuse element; a port disposed in the structural housing to be in fluid communication with the interior volume and configured to provide fluid to the interior volume; an additional port disposed in the structural housing and configured to remove the fluid from the interior volume; and a sensor for providing a sensor signal indicative of an operating state of the fuse; and a control circuit configured to monitor at least one characteristic of the fuse during operation, Wherein, if the operating state indicates an electrical short circuit, the fluid is controlled to be discharged from the fuse to cause the fuse to fail.

8. The system of claim 7, wherein the sensor is configured to sense at least one property of the fluid, wherein the sensor is communicatively coupled to the control circuit.

9. The system of claim 8, wherein the at least one characteristic comprises a temperature of a fluid disposed in the interior volume.

10. The system of claim 7, further comprising a fluid management system configured to circulate a fluid flow through an interior volume of the structural shell, wherein fluid in the interior volume is supplied by the fluid flow.

11. The system of claim 10, wherein the fluid management system comprises a pump, a fluid conduit, and accessories configured to manage the fluid flow.

12. The system of claim 10, wherein the control circuit is coupled to the fluid management system, and wherein the control circuit is further configured to provide a control signal to the fluid management system to control the fluid flow.

13. The system of claim 12, wherein the control circuit is further configured to provide the control signal to the fluid management system to control the temperature of the fuse.

14. A method for managing a fuse affected by a fluid, the method comprising: monitoring one or more sensor signals generated by a sensor element disposed in a port of a structural housing of a fuse subject to the fluid, wherein the one or more sensor signals are indicative of an operational state of the fuse; applying an electrical current to one or more bus bars of the battery system, wherein a fuse element is disposed within the interior volume of the structural housing and electrically coupled to the one or more bus bars; as well as generating a control signal for controlling a fluid flow, the fluid flow being configured to flow through the interior volume to affect a temperature of the fuse element, wherein the fluid is provided from a port disposed in the structural housing and removed through an additional port disposed in the structural housing, and if the operating condition indicates an electrical short circuit, the fluid is controlled to be discharged from the fuse to cause the fuse to fail.

15. The method of claim 14, wherein monitoring the one or more sensor signals comprises monitoring a temperature sensor signal of the sensor, wherein the sensor comprises a temperature sensor configured to sense a temperature of the fluid flow, and wherein generating the control signal comprises generating the control signal to control the temperature of the fuse element.

16. The method of claim 14, further comprising determining that a fault has occurred based on the one or more sensor signals.

Images