Hybrid fault protection circuit for high power periodic loads.

Abstract

The hybrid fault protection circuit (HFPC) includes an input, an output, a resistor-fuse circuit, an electrically controlled safety switching device (ESSD), and an overload protection module (OPM). The input receives power from a power source. The output outputs power to a high-power periodic load. The resistor-fuse circuit includes a resistor and one or more fuses connected together in series with the resistor. The ESSD includes a coil and contacts. The contacts are connected in parallel with the resistor-fuse circuit. The OPM enables the HFPC by energizing the coil and closing the contacts to supply load current from the input to the output through the contacts when no fault downstream of the HFPC is present, detects a fault downstream of the HFPC, and, in response to detecting the fault, opens the contacts to cause the fault current to flow through the one or more fuses rather than across the contacts.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Patent Application No. 18 / 418,928, filed January 22, 2024, which claims the benefit of U.S. Provisional Patent Application No. 63 / 440,581, filed January 23, 2023. The disclosures of the above-cited applications are incorporated herein by reference in their entireties.

[0002]

[0002] The present disclosure relates to fault protection circuits. [Background technology]

[0003] The background art discussion provided herein is generally intended to provide a context for the present disclosure. Works of currently cited inventors to the extent described in this background art section, and aspects of the discussion that may not otherwise be identified as prior art at the time of filing, are not admitted, expressly or implicitly, as prior art to the present disclosure.

[0004]

[0004] A high-voltage power supply system used to supply power to high-voltage electric vehicles from overhead contact wires may include multiple substations. The substations supply power to the overhead contact wires, which in turn supply direct current (DC) power to the high-voltage vehicles. The power supply system in each vehicle may include, for example, one or more power sources, such as an engine, a trolley power circuit, and / or one or more battery packs that provide DC power to a DC bus bar. The trolley power circuit represents a circuit for transferring the DC voltage in the overhead contact wire to a DC voltage on the DC bus bar. One or more inverters convert the DC voltage on the DC bus bar to one or more alternating current (AC) voltages, which are respectively supplied to one or more loads on the vehicle. The loads may include motors, fans, brake choppers, etc. Summary of the Invention

[0005] A hybrid fault protection circuit is disclosed, including an input, an output, a resistor fuse circuit, an electrically controlled safety switching device, and an overload protection module. The input is configured to receive power from a power source. The output is configured to output power to one or more high-power periodic loads. The resistor fuse circuit includes one or more resistors and one or more fuses connected together in series with the one or more resistors. The electrically controlled safety switching device includes a coil and contacts. The contacts are connected in parallel with the resistor fuse circuit. The overload protection module is configured to enable the hybrid fault protection circuit by energizing the coil and closing the contacts to supply load current from the input to the output through the contacts when no fault downstream of the hybrid fault protection circuit is present; detect a fault downstream of the hybrid fault protection circuit; and, in response to detecting the fault, open the contacts to cause the fault current to flow through the one or more fuses rather than across the contacts.

[0006] In other features, the one or more resistors comprise a plurality of resistors.

[0007] In another feature, the impedance of the resistor fuse circuit is higher than the impedance of the contacts when closed, so that most of the current flowing from the input to the output flows through the contacts when closed.

[0007]

[0008] In another feature, the impedance of the resistor fuse circuit is higher than the impedance of the contacts when closed, so that 95% or more of the current flowing from the input to the output flows through the contacts when closed.

[0008]

[0009] In other features, the electrically controlled safety switching device is implemented as a circuit breaker, a contactor, or a high speed mechanical switch.

[0010] In other features, the one or more fuses include a plurality of fuses connected in parallel.

[0009]

[0011] In other features, the hybrid fault protection circuit further includes one or more current sensors configured to detect at least one of a power supply current from the input and a contact current through the contacts, and the overload protection module is configured to detect the fault based on at least one of the power supply current from the input and the contact current through the contacts.

[0010]

[0012] In other features, the blow time of the one or more fuses is greater than at least one of i) the time for the contacts to separate farther than a minimum restriking distance (ARD) and ii) the time for the overload protection module to cause the contacts to separate farther than the minimum ARD.

[0011]

[0013] In other features, the overload protection module is configured to detect the fault, exceed the minimum ARD, and then determine whether to operate in limp mode after opening the contacts, and to reclose the contacts in response to determining to operate in limp mode.

[0012]

[0014] In another feature, a machine is disclosed that includes a DC link including a plurality of DC link rails, a hybrid fault protection circuit, an output of the hybrid fault protection circuit connected to the DC link, and one or more high power periodic loads that receive power from the DC link. In another feature, the machine further includes one or more power sources that provide power to the DC link. In another feature, the one or more power sources include at least one of an engine and a power storage module. In another feature, the machine further includes a trolley pantograph connected to the input and configured to receive power from an overhead contact wire.

[0013]

[0015] In another feature, a power supply system is disclosed that includes a hybrid fault protection circuit and one or more substations that provide power to an input of the hybrid fault protection circuit via an overhead contact wire.

[0014]

[0016] In another feature, a vehicle is disclosed that includes a hybrid fault protection circuit, a power source that provides power to the hybrid fault protection circuit, and one or more high power periodic loads that receive power from the output of the hybrid fault protection circuit. In another feature, the power source is an engine, a power storage module, or a trolley pantograph.

[0015]

[0017] In another feature, a method of operating a hybrid fault protection circuit is disclosed. The method includes enabling the hybrid fault protection circuit, the hybrid fault protection circuit including an electrically controlled safety switching device connected in parallel with a resistor fuse circuit, the electrically controlled safety switching device including a coil and contacts, the resistor fuse circuit including one or more resistors connected together in series with one or more fuses. Enabling the hybrid fault protection circuit includes energizing the coil to close the contacts and to supply a load current to one or more high power periodic loads through the contacts. The method further includes detecting at least one parameter of the hybrid fault protection circuit, comparing the at least one parameter to at least one threshold to detect a fault downstream of the hybrid fault protection circuit, and, in response to detecting the fault, opening the contacts of the electrically controlled safety switching device to cause the fault current to flow through the one or more fuses rather than across the contacts.

[0016]

[0018] In other features, the at least one parameter includes at least one of a power supply current and a current through the contacts.

[0019] In other features, the at least one threshold comprises a current threshold and an energy threshold.

[0017]

[0020] In other features, the method further includes detecting a power supply current supplied to the hybrid fault protection circuit; determining whether one or more fuses are blown based on the detected power supply current; and, in response to detecting that the one or more fuses are blown, operating in a limp mode including closing contacts to allow current to flow from an input of the hybrid fault protection circuit to an output of the hybrid fault protection circuit.

[0018]

[0021] Further scope of applicability of the present disclosure will become apparent from the detailed description, claims, and drawings. The detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

[0019]

[0022] The present disclosure will become more fully understood from the detailed description and the accompanying drawings. [Brief explanation of the drawings]

[0020] [Figure 1]

[0023] FIG. 1 is a functional block diagram of an exemplary power supply system including a hybrid fault protection circuit (HFPC) according to the present disclosure. [Figure 2]

[0024] FIG. 1 is a functional block diagram of an exemplary power supply system that provides power to a vehicle including an HFPC via overhead contact wires, according to an embodiment of the disclosure. [Figure 3]

[0025] 1 is a diagram of an exemplary power system for a vehicle including an HFPC, according to an embodiment of the present disclosure. [Figure 4]

[0026] FIG. 1 is a diagram of an exemplary HFPC, according to an embodiment of the present disclosure. [Figure 5]

[0027] FIG. 1 illustrates a method of operating an HFPC according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0021]

[0028] In the drawings, reference numbers may be reused to identify similar and / or identical elements.

[0029] Electric vehicles (EVs), sometimes referred to as zero-emission vehicles, can include low-voltage drive systems (e.g., drive systems of 800 volts (V) or less). EVs including low-voltage drive systems include a low-voltage energy storage module (ESM), e.g., a battery pack and / or fuel cell, that provides up to 800V. Traditional EVs are used in automobiles by individual consumers and businesses for small, lightweight, and low-load applications. Zero-emission vehicles can also be used in mining and construction environments. Mining and construction vehicles tend to be large, heavy, and have high power and high DC voltage (e.g., 2800V) requirements. As an example, mining and construction vehicles may receive DC power from overhead DC power lines capable of delivering 2800V for longer periods of time.

[0022]

[0030] High-power DC loads, such as mining and construction vehicles that receive power from overhead contact wires, may be protected from faults using fuses or circuit breakers (CBs). A fault may occur, for example, when a short circuit occurs in the load, e.g., when the DC bus wires are shorted to each other or to ground. This may cause an inrush of current from one or more power sources to the location of the short circuit.

[0023]

[0031] During normal operation, when the load is large and involves slow, repetitive power changes, the fuse may experience large current and temperature fluctuations that result in a short fuse life. This is called thermal cycling of the fuse due to large cyclic loads. To reduce the current and temperature fluctuations of each fuse and therefore reduce the thermal stress on the fuse, multiple fuses may be connected in parallel. This increases the fuse life, but requires a large amount of abnormal current to blow the fuse. When the abnormal (or "let-through") current is large enough to blow the fuse, corresponding circuit components and / or downstream loads may be damaged. Therefore, in some instances, a protection circuit consisting of a fuse is not a viable option.

[0024]

[0032] High-power, high-speed CBs can be used instead of fuses to quickly interrupt fault currents. However, high-power, high-speed CBs tend to be expensive, heavy, and bulky, requiring space between the CB and other surrounding vehicle components. For example, a high-power, high-speed CB cannot simply be placed in a cabinet because arcing can occur between the CB and the cabinet when a fault occurs. Additionally, due to inductances in the CB, power lines, transformers, reactors, etc., opening the CB contacts when a fault occurs involves arcing until the inductive energy associated with the fault dissipates. To accommodate arcing, CBs include large arc chutes that can occupy a significant amount of space. Vehicles tend to have a small amount of available space for protection circuits. Due to the associated cost, weight, size, and space requirements, high-power, high-speed CBs are not a practical and / or feasible option for vehicles in some instances.

[0025]

[0033] Examples described herein include HFPCs configured to protect high-power cyclic loads and other circuits from faults, such as short circuits. Each HFPC includes one or more fuses and an electrically controlled safety switching device (ESSD), such as a CB, contactor, or fast mechanical switch (FMS). The contacts of the ESSD can be actuated electronically, hydraulically, or pneumatically. The HFPCs are configured to provide the benefits of fuses and ESSDs while eliminating their drawbacks. Each HFPC includes one or more balancing resistors connected in series with one or more fuses, referred to as a resistor fuse circuit. The resistor fuse circuit is connected in parallel with the ESSD. The fuses interrupt fault current (referred to as "clearing the fault"). The ESSDs protect the fuses from high-power load cycles. The ESSDs conduct the load current during normal operation when no faults are present, which prevents thermal fatigue in the fuses and simplifies fuse selection. The fuses are low-resistance fuses capable of withstanding the maximum system voltage. The ESSD is a low-cost, high-speed device configured to initiate current transfer to a fuse in the event of a fault, and the described HFPC protects the ESSD from being hit by high-voltage arcing during a fault.

[0026]

[0034] The configuration of each HFPC allows for the elimination of arc chutes. Minimal voltage is applied to the fuse during a fault event and the pre-arc phase of the HFPC fuse melting. The HFPC ESSD opens its contacts without arcing. This allows the ESSD to be implemented as a simple, low-cost, low-voltage high-speed CB, contactor, or high-speed mechanical switch. In certain applications, the HFPC can be used in place of a pyrotechnic circuit breaker.

[0027]

[0035] The disclosed and described HFPC is a reliable, compact, and low-cost circuit that removes fault currents and prevents damage to equipment. The HFPC disclosed herein requires less space than conventional high-speed, high-power CBs and provides reliable fault protection using a minimum number of fuses and low-power ESSDs. As explained in more detail below, specifying fuses is not difficult. The HFPC is also simple to test, and when implemented in a vehicle, the HFPC allows the vehicle to operate in limp mode if a fault occurs. During limp mode, the vehicle can, for example, be driven to a repair shop at a reduced speed and current to receive maintenance.

[0028]

[0036] FIG. 1 shows an exemplary power system 100 including a power source 102, an HFPC 104, and a load 106. The power source 102 may include one or more substations, overhead contact wires, an internal combustion engine including a traction alternator and rectifier, one or more energy storage modules, bus bars, etc. The power source 102 may be implemented independently of a machine to power the machine, or may be implemented on the machine. The machine may be, for example, a conveyor, a crusher, a vehicle, a haul truck, a roller mill, a surface mining truck, an underground mining truck, a battery-powered vehicle, a rock hauler, a hybrid mining loader, a trolley assist machine, an off-road truck, etc. The power source 102 may be a DC or alternating current (AC) power source. The load 106 may be a DC or AC load.

[0029]

[0037] The HFPC 104 is configured to protect its components and the load 106 from current surges caused by faults. The fault may be, for example, a short circuit downstream of the HFPC 104. The HFPC 104 may operate with DC or AC loads and fault currents. Examples of the HFPC 104 and its implementation are shown and described in connection with FIGS. 2-5.

[0030]

[0038] Each of the loads may be a machine, a vehicle, or a load on a machine or vehicle. Each of the loads may be an industrial load. In one embodiment, the power source 102 supplies power to multiple machines and / or vehicles via overhead contact lines. In another embodiment, the power source 102 is mounted on the machine and / or vehicle and supplies power to multiple loads on the machine and / or vehicle. Each of the loads is subjected to high power cycles and thermal fuse cycles. The loads may operate at maximum power, turn off the power, then turn the power back on, and repeat this cycle, and are therefore referred to as cyclic loads. When on the machine and / or vehicle, the loads may include fans, motors, storage drives, etc. Each of the loads may be a DC or AC load.

[0031]

[0039] 2 shows a power supply system 200 that provides power to vehicles 204 via overhead contact wires 202. A power line terminal 206 supplies power to a substation 208, which in turn supplies power to the overhead contact wires 202. A trolley pantograph 210 receives power from the overhead contact wires 202 and provides power to the vehicles 204.

[0032]

[0040] Vehicle 204 may include a line reactor 220, a trolley box 212, a power source 214, and a load 216. Trolley box 212 includes an HFPC 218. Line reactor 220 prevents interference between a DC link voltage (or capacitor voltage) at a DC link 222 of vehicle 204 and the DC link voltage of other power systems connected to overhead contact wire 202. The other power systems may be implemented within other respective vehicles, for example.

[0033]

[0041] The trolley box 212 enables the trolley pantograph 210 to remain in contact with the overhead contact wire 202 and to safely and quickly connect or disconnect the DC link 222 to or from the overhead contact wire 202. The trolley box 212 may include only the HFPC 218 or may include the HFPC 218 in combination with other circuit components, such as one or more fuses, circuit breakers, sensors (e.g., voltage and current sensors), switches, etc. Sensors may be used to ensure that the contact wire voltage is within a predetermined range before connecting the DC link 222 to the overhead contact wire 202 to prevent surges in current from or to the DC link 222 to or from the overhead contact wire 202. The HFPC 218 and any included switches of the trolley box 212 may be used to connect and disconnect the DC link 222 to the trolley pantograph 210 and thus the overhead contact wire 202. Examples of the HFPC 218 are described below in connection with Figures 4-5.

[0034]

[0042] The power source 214 may include an internal combustion engine including a traction alternator and a rectifier, one or more energy storage modules, etc., that supplies power to the DC link 222. The loads may include high power periodic loads, low power periodic loads, and non-periodic loads and receive power from the DC link 222.

[0035]

[0043] 3 shows an example power system 300 for a vehicle including multiple power sources 302, 304, 306, a conversion circuit 307 including multiple two-level buck-boost DC-DC converters 308, 310 (referred to as DC-DC converters 308, 310), and multiple inverters 312 connected to respective loads 314, which may have regenerative capabilities. Power sources 302, 304, 306 are example power sources and may be replaced with other power sources. In the example shown, power source 302 is implemented with an engine 320, an alternator 321, and a rectifier 322.

[0036]

[0044] The power source 304 is implemented as a trolley pantograph. The power source 306 is implemented as a group (or groups) of energy storage modules (ESMs). The engine 320 is connected to an alternator 321, which supplies AC power to a rectifier 322. A field regulator 324 regulates the voltage output from the alternator 321. The rectifier 322 outputs a DC voltage to a DC link 326, which includes DC rails 326A and 326B. The rectifier 322 is an AC-to-DC rectifier. The DC link 326 may be referred to as a DC bus, which includes bus bars (or DC rails) 326A and 326B. Each of the DC rails 326A and 326B may be positive or negative; thus, there may be one positive rail and one negative rail, two positive rails, or two negative rails.

[0037]

[0045] Trolley pantograph 304 receives DC power from the overhead contact wire and supplies the DC power to line reactor 330 and trolley box 332. Line reactor 330 prevents interference between the DC link voltage (or capacitor voltage) at DC link 326 of power supply system 300 and the DC link voltage of other power systems connected to the overhead contact wire. Power supply system 300 may be implemented for a host vehicle, and other power systems may be implemented within other respective vehicles.

[0038]

[0046] The trolley box 332 allows the trolley pantograph 304 to remain in contact with the overhead contact wire and to safely and quickly connect or disconnect the DC link 326 to or from the overhead contact wire. The trolley box 332 includes the HFPC 333 and may include other circuit components. The trolley box 332 may include one or more fuses, circuit breakers, sensors (e.g., voltage and current sensors), switches, etc. Sensors may be used to ensure that the contact wire voltage is within a predetermined range before connecting the DC link 326 to the overhead contact wire to prevent current surges from or to the DC link 326 to or from the overhead contact wire. The switches on the HFPC 333 and / or the trolley box 332 can be used to connect and disconnect the DC link 326 to the trolley pantograph 304 and further to the overhead trolley wires.

[0039]

[0047] The HFPC 333 protects its components and components and devices downstream from current surges caused by faults downstream of the HFPC 333. As some examples, the faults may represent short circuits between busbars 326A, 326B, between busbar 326A and ground reference, between busbar 326B and ground reference, and / or between components downstream of the DC link 326. If not protected against these types of faults, these types of faults may result in inrush of current from the trolley pantograph 304 through the trolley box 332 to the DC link 326 and / or to one or more loads, causing damage to components and / or devices. The HFPC 333 interrupts the fault current. The HFPC 333 may protect against, for example, an inrush of 25,000 to 40,000 amperes (A) of current being passed from the trolley pantograph 304 to the DC link 326, preventing damage to the DC-DC converters 308, 310, the inverter 312, and the load 314. Examples of the HFPC 333 are described below in connection with Figures 4-5.

[0040]

[0048] The group of ESMs 306 may include multiple subgroups of ESMs. For example, each subgroup of ESMs may be connected to one or more of the DC-DC converters 308, 310. In the example shown, the first subgroup of ESMs 334 is connected to the first DC-DC converter 308 and includes ESM 335. The second subgroup of ESMs 336 is connected to both DC-DC converters 308, 310 and includes ESM 337. The third subgroup of ESMs 338 is connected to the second DC-DC converter 310 and includes ESM 339. When discharging, the group of ESMs (or power sources) 306 supplies power to the DC link 326. When charging, the group of ESMs 306 may sink power received from (i) one or more of the power sources 302, 304 and / or (ii) one or more of the regenerative loads 314 via corresponding ones of the inverters 312. Each of the ESMs 335, 337, 339 and other ESMs disclosed herein may include battery cells, fuel cells, switches, resistors, control circuits, etc. The ESMs 335, 337, 339 and other ESMs disclosed herein may include pumps, light sources, heaters, and / or other DC loads and / or sources instead of or in addition to battery cells or fuel cells. The loads 314 may include motors, DC-DC choppers, auxiliary loads (e.g., fans), etc. Some of the loads 314 may be capable of supplying power, for example, a motor operating in quadrant 2 or 4.

[0041]

[0049] The conversion circuit 307 further includes reactor sets 340 and 341 connected between the DC-DC converter 308 and the power supply 306. Reactor sets 342 and 343 are connected between the DC-DC converters 308 and 310 and the power supply 306. Reactor sets 344 and 345 are connected between the DC-DC converter 310 and the power supply 306. Each of the reactor sets 340 to 345 may be realized as a respective collection of one or more reactors (or inductors). Each reactor (or inductor) in each of the reactor sets 340 to 345 is connected to a respective phase of the corresponding one of the DC-DC converters 308 and 310. First terminals of the reactors in each of the reactor sets 340 to 345 are connected to a respective phase of the corresponding one of the DC-DC converters 308 and 310 via a respective line (e.g., line X, where X is an integer greater than or equal to 1). The second terminals of the reactors in each of the reactor sets 340-345 are connected to each other and, for example, to the same contactor, disconnector, or ESM group, depending on whether a contactor and / or disconnector is connected between that reactor set and the corresponding ESM group. The wrapping of multiple reactors and corresponding phase legs in the reactor sets 340-345 enables interleaving operation, as described in more detail below. Interleaving operation may be provided for one or more reactor sets of an ESM group.

[0042]

[0050] A first set of contactors 346 and a first set of disconnectors 348 may be connected between the reactor set 340, 342, 344 and the power source 306. A second set of disconnectors 350 and a second set of contactors 352 may be connected between the power source 306 and the reactor set 341, 343, 345.

[0043]

[0051] Contactors 346, 352 are electrically driven contactors that can be enabled and disabled by control module 360 ​​to connect and disconnect subgroups 334, 336, 338 to and from DC link 326. Disconnectors 348, 350 are manual switches that can be switched by a person for safety reasons to isolate subgroups 334, 336, 338 from DC link 326.

[0044]

[0052] Although three power sources 302, 304, 306 are shown as providing power to and / or connected to DC link 326, any number of power sources may provide power to and / or be connected to DC link 326.

[0045]

[0053] DC-DC converters 308, 310 are bidirectional converters, so that in operation, DC-DC converters 308, 310 convert the DC voltage across the subgroups of ESMs 334, 336, 338 to a DC voltage at DC link 326, and vice versa. The DC-DC converters may be replaced by, connected similarly to, and / or configured similarly to any of the DC-DC converters disclosed herein. The conversion circuit 307, in combination with DC-DC converters 308, 310 and reactor sets 340-345, has a virtual ground.

[0046]

[0054] The power supply system 300 may include various sensors 362, such as current sensors, voltage sensors, temperature sensors, etc. By way of example, current and voltage sensors may be used to detect the current through and voltage at the trolley box 332, the current and voltage at the DC link 326, the current and voltage at each of the ESMs 335, 337, 339, the level of current flowing to and from the reactor sets 340-345, etc. Based on the outputs of the sensors 362, the control module 360 ​​may control the operation of the power supply 302, the state of the switches in the trolley box 332, the state of the switches in the DC-DC converters 308, 310, the state of the contactors 346, 352, etc. The control module 360 ​​may control switches in the trolley box 332 based on the output of sensors in the trolley box 332 to connect and / or disconnect the DC link 326 to the trolley pantograph 304 and thus the overhead wires. The control module 360 ​​may control the state, switching frequency, and / or duty cycle of the switches of the DC-DC converters 308, 310 to set the voltages across the subgroups 334, 336, 338. By controlling the on-duration of the switches of the DC-DC converters 308, 310, the average output voltage of each phase leg can be adjusted to any voltage within a predetermined range (e.g., 0 to 800 V), as described in more detail below.

[0047]

[0055] A discharge ground circuit 370 may be connected across the rails 326A, 326B. An example of the discharge ground circuit is shown in Figure 3 and may include a discharge resistor to passively discharge the DC link 326 when power is turned off. The discharge ground circuit 370 may be configured so that the intermediate voltage of the DC link 326 floats above, is centered around, or is floating below chassis ground.

[0048]

[0056] 4 shows an exemplary HFPC 400 including an input 402, a resistor fuse circuit 404, an output 406, and an ESSD 408. The ESSD 408 is connected in parallel with the resistor fuse circuit 404 between the input 402 and the output 406. The input 402 receives power from a power source (e.g., the power source of FIG. 1, the overhead contact wire of FIG. 2, or other power source). The output 406 provides power to one or more loads (e.g., the loads of FIG. 1, the DC bus of FIGS. 2-3, or other loads). The current from the power source is I S The current flowing through the load is I L It is expressed as:

[0049]

[0057] The resistor fuse circuit 404 includes one or more balancing resistors (one balancing resistor R bal ) and one or more fuses (fuses F1 to F N The fuses are connected in parallel. The balancing resistors increase the series resistance of the resistor fuse circuit 404 so that, when no fault is present, most of the current flows through the ESSD 408 instead of through the fuses. The resistance of the resistor fuse circuit 404 is greater than the resistance of the ESSD 408, and more specifically, greater than the resistance of the closed contacts 410 of the ESSD 408. The power supply current I S flow through the contacts 410 when closed, and the supply current I S The balancing resistor is sized so that the remaining portion (e.g., 5% or less) of flows through the fuse. The current through the fuse is I F As an example, the resistance of the one or more balancing resistors may be 0.5 to 2.0 milliohms (mΩ). The ESSD 408 includes contacts 410 (also called pairs or sets of contacts) and a coil 412 that closes the contacts 410 when energized. The ESSD 408 may be implemented as a CB, a contactor, or a fast mechanical switch (FMS).

[0050]

[0058] An overload protection module (OPM) 414 may be included and may measure the power supply current I via a current sensor 416. Sand / or detects the current I passing through the contact via a current sensor 418. K Detects the power supply current I S is the current supplied from the power supply to the load via the HFPC400. i) Power supply current I S and / or the current through the contact I K When I exceeds a respective predetermined current threshold, and / or ii) exceeds a predetermined energy threshold, the OPM 414 de-energizes the coil 412 and opens the contacts 410. 2 When the energy through the contact 410, denoted as t, exceeds a predetermined energy threshold, the contact 410 is opened, where I is equal to I S and / or I K where t is time. When the current level through contact 410 is excessively high and / or a large amount of current is provided for an extended period of time, a fault is detected and contact 410 opens. The current level threshold depends on the current limit of the load. The length of time depends on the length of time the ESSD and / or load can experience an overcurrent load. Opening contact 410 occurs when the current flows past fuse F 1-N This causes the fuse F 1-N This causes the fuse F to melt. 1-N This causes an arc to occur. 1-N The arc discharge at F to zero. The fuse current I F Abnormal current I flows as S The resulting low voltage across the resistor fuse circuit 404 protects the contacts 410 from arcing.

[0051]

[0059] During normal operation and when a load is present, contacts 410 are closed and a continuous load current I L The current I passing through the fuse FSince I is approximately equal to zero, there is negligible loss in the balancing resistor. When a fault occurs, the OPM 414 opens the contacts and transfers the fault current to a fuse, which clears the fault. In one embodiment, the OPM 414 is implemented as an analog circuit including a current transducer, and when the current is greater than a threshold, the analog circuit de-energizes the coil 412 and opens the contacts 410. In another embodiment, the OPM 414 converts the current I 2 t, and implemented as a digital circuit and / or processor capable of computing I 2 When the threshold value of t is exceeded, the coil 412 is de-energized and the contacts 410 are opened.

[0052]

[0060] The ESSD 408 includes normally open contacts 410. During start-up of the HFPC 400, power is supplied to the ESSD 408 to close the contacts, thereby "enabling" the ESSD 408. When the contacts 410 are in a closed state, the ESSD 408 remains enabled. The load current I L Fuse F is intact (unblown) 1-N If current is allowed to flow through the ESSD 408, the ESSD 408 opens the contacts 410 at zero voltage (ie, when power is removed from the ESSD 408).

[0053]

[0061] As an example, the normal load current through the ESSD 408 may be 3000 A, and when a fault is present, the current may suddenly increase to 5000 A. If the current remains at 5000 A for 2 ms, the ESSD 408 may open the contacts 410. Thus, when the current is higher than a predetermined threshold for a predetermined period of time, the contacts 410 may open. As the level of current increases, the length of time before triggering the contacts to open decreases.

[0054]

[0062] Hughes F 1-N can be easily defined for each application. 1-NThe characteristics of the fuses, such as resistance, size, material, number of fuses connected in parallel, peak voltage, overload voltage, duration to withstand overload (or fuse blow time), operating current level, etc., are selected based on the maximum system operating voltage, system operating current level, duration of the fault, and tripping speed of the ESSD 408. 2 Fuse F to meet the threshold of t 1-N For example, a fuse may be selected to withstand a higher than predetermined level of power for a predetermined period of time. 1-N The pre-arcing duration of the fuse F is coupled to the opening speed of the contacts 410 of the ESSD 408. 1-N may be selected to withstand the maximum system voltage and reach a peak arc voltage of 150% of the rated system voltage. As an example, a fuse for a 3000 volt (V) system will arc, and after the fuse blows, the arc voltage may be 4000V to 5000V. Thus, fuse F 1-N removes abnormal currents and reduces damaging current levels, voltage levels, and I 2 The ESSD408 does not actively remove the fault, but rather passes the fault current through the fuse F 1-N Move to Fuse F 1-N is within the system voltage limits and the current and / or I of the HFPC 400 and downstream loads 106, 216, 314, conversion circuit 307, and energy ESM 306. 2 The t limit is chosen to remove the anomaly before it is exceeded.

[0055]

[0063] In the event of a fault, fuse F is configured so that it does not melt and / or blow until after the ESSD contacts 408 are separated by more than a minimum re-arcing distance (ARD). 1-N This is done to prevent the ESSD 408 from interrupting the fault current and accompanying arcing. The contacts 410 of the ESSD 408 begin to open, preventing the inrush of current due to the fault from reaching the fuse F. 1-N Flows through the fuse F 1-NAfter the fuse F has blown and interrupted the fault current, the contacts 410 are separated without arcing by more than the minimum ARD and are capable of interrupting i) the maximum fuse arcing voltage and ii) the maximum system power voltage. In the fully open position, the contacts are capable of interrupting the maximum system power voltage and the maximum fuse arcing voltage. 1-N When fuse F melts and starts arcing, 1-N dissipates the energy associated with the anomaly and eliminates the anomaly. Fuse F 1-N is specifically selected as a slow acting fuse, and ESSD 408 is configured to open its contacts quickly upon detection of a fault. By way of example, contacts 410 may require 2.0 to 3.0 milliseconds (ms) to separate further than the minimum ARD, making fuse F 1-N The fuse F will finish fusing, arcing will begin after 4.0 ms, and the fault can be cleared after 8.0 ms. Therefore, there is a relationship between the contact opening characteristics and the fuse fusing time. Therefore, the fuse F will finish fusing before the contacts are separated farther than the minimum ARD. 1-N A minimum number of fuses (e.g., 2-4) connected in parallel can be used in the HFPC400. Due to the construction of the HFPC400, fuse F 1-N does not undergo thermal cycling, and therefore fuse F 1-N does not need to be derated from 100% to a lower percentage (e.g., 80%, 60%, or 40%) to survive for a longer period, as is the case with fuse-only fault protection circuits.

[0056]

[0064] When resistor fuse circuit 404 is intact, there is no voltage across contacts 410 as they are closed and begin to separate, and therefore no arcing is experienced in ESSD 408. When contacts 410 begin to separate, the resistance across contacts 410 increases and becomes significantly greater than the resistance of resistor fuse circuit 404. This resistance change causes power supply current to flow through resistor fuse circuit 404, preventing arcing across the contacts of ESSD 408.

[0057]

[0065] The contacts 410 and operating coil 412 of the ESSD 408 may be implemented as part of or replaced by a high-speed mechanical switch controlled by the OPM 414. To ensure that the fuse arcing voltage does not exceed the minimum ARD across the contacts when the fuse blows, and therefore does not create an arc across the contacts 410, the contacts 410 may have a small mass and a strong opening mechanism so that when the coil 412 is de-energized, the contacts begin to separate with a very short delay (e.g., 2-3 ms) and then accelerate rapidly (e.g., 5 m / s).

[0058]

[0066] The current sensors 416, 418 may measure current at a location between the power source and the load where abnormal current may occur. As the contacts 410 begin to open, the abnormal current I K is smoothly transferred to the low impedance fuse, which then transfers the entire fault current to I F The voltage drop across the unblown fuse (still in the pre-arcing stage) and R bal is small enough that it is not possible for the contacts 410 to arc. This may significantly reduce the size and cost of the ESSD 408 and allow the use of simple contactors or high-speed mechanical switches. The contacts 410 do not require any means for dissipating the arc, such as the arc chutes of a conventional CB.

[0059]

[0067] 5 shows a method of operating an HFPC (eg, the HFPC of FIGS. 1-4). The operations of FIG. 5 may be performed repeatedly. The operations may be performed, for example, by the HFPC 400 of FIG.

[0060]

[0068] The method may begin at 500. At 501, the OPM 414 determines whether a majority of the current is flowing through the fuse F 1-N HFPC 400 is enabled by closing contacts 410 to allow current to flow through ESSD 408 instead of through the HFPC 400.

[0061]

[0069] At 502, a first parameter associated with the HFPC 400 is measured, such as a current level and / or other parameter. The current level may be measured via a current sensor (e.g., current sensors 416, 418).

[0062]

[0070] At 504, a second parameter may be determined based on the first parameter, e.g., a current energy level I 2 t can be determined based on the measured current.

[0071] One or more thresholds may be obtained (e.g., located), calculated, and / or determined at 506. As some examples, a power supply current threshold, a contact current threshold, an energy threshold, and / or a temperature threshold may be obtained, calculated, and / or determined.

[0063]

[0072] At 508, one or more of the first parameters and / or one or more of the second parameters are compared to thresholds to determine whether an anomaly exists. At 510, it is determined whether an anomaly exists. If an anomaly exists, operation 512 is performed; if an anomaly does not exist, operation 502 is performed. For example, this may be performed when the power supply current and / or contact current exceeds one or more current thresholds, when the energy through the contacts exceeds an energy threshold for a monitored period of time, and / or when the detected temperature exceeds a predetermined temperature (e.g., 85-200°C).

[0064]

[0073] At 512, in response to detecting the anomaly, the contacts of the ESSD 408 are opened, turning on the fuse F 1-N The OPM 414 may de-energize the coil 412 to open the contacts 410. At 513, the OPM 414 transfers the power supply current I S At 514, the OPM 414 detects the fuse F 1-N It determines whether the power supply current I is blown. If it is blown, the fuse cuts off the abnormal current. Sis zero, operation 516 may be performed, and the power supply current I S When is not zero, operation 513 may be performed.

[0065]

[0074] At 516, the OPM 414 or other control module, for example, a vehicle control module, may determine whether to operate in limp mode. If operating in limp mode, operation 518 may be performed; if not operating in limp mode, the method may end at 520.

[0066]

[0075] In conventional systems that include fault protection circuits using only fuses, if the fuse is blown, the corresponding power source (e.g., overhead contact wire) will not provide power to the load. In the disclosed HFPC 400 configuration, the fuse F is used to power the vehicle motor, for example, to drive the corresponding vehicle to a gas station for maintenance. 1-N After a contact 410 is blown, the contact 410 can be further closed to allow power from the corresponding power source to be supplied through the HFPC 400. This can be performed at 518 and can be based on a stored flag allowing limp mode operation, a system request, and / or a user input requesting operation in limp mode. The vehicle can be limited in operation while operating in limp mode. The current drawn from the power source can be limited, the vehicle's speed can be limited, the voltage supplied to the output of the HFPC 400 can be limited (e.g., a predetermined percentage, such as 30% or 50% of the maximum power voltage), etc.

[0067]

[0076] The operations described above are intended to be illustrative examples. Operations may be performed sequentially, synchronously, simultaneously, continuously, during overlapping time periods, or in a different order depending on the application. Furthermore, any of the operations may not be performed or may be skipped depending on the implementation and / or sequence of events.

[0068]

[0077] The above-described examples include HFPCs that include ESSDs that protect fuses from large cyclical changes in load current, which can excessively shorten fuse life and / or significantly increase the number of fuses required. As a result, fuses with lower nominal current ratings can protect the load from damage and allow the ESSD 408 to open at lower contact voltages without arcing. The disclosed examples include smaller, brighter, and less expensive protection circuits than conventional high-speed, high-voltage circuit breakers, which include bulky arc chutes and impose large clearance requirements on adjacent equipment. In applications where multiple parallel fuses may be used, HFPCs require fewer fuses and allow smaller fault currents to flow before the fault is cleared, improving protection and reducing costs. The examples disclosed herein are applicable to a variety of industrial applications.

[0069]

[0078] The foregoing description is merely exemplary in nature and is not intended to limit the disclosure, its application, or uses in any respect. The broad teachings of the present disclosure may be embodied in various forms. Accordingly, while the present disclosure includes specific examples, the true scope of the present disclosure should not be limited to those specific examples, as other variations will become apparent with reference to the drawings, the specification, and the following claims. It should be understood that one or more steps in a method may be performed in a different order (or simultaneously) without altering the principles of the present disclosure. Furthermore, although each of the embodiments has been described above as having specific features, any one or more of those features described in connection with any embodiment of the present disclosure may also be implemented in any of the other embodiments and / or may be combined with features of any of the other embodiments, even if that combination is not explicitly described. In other words, the described embodiments are not mutually exclusive, and substitution of one or more embodiments for one another remains within the scope of the present disclosure.

[0070]

[0079] Spatial and functional relationships between elements (e.g., between modules, circuit elements, semiconductor layers, etc.) are described using various terms, including "connected," "engaged," "coupled," "adjacent," "adjacent to," "on top of," "above," "below," and "located." Unless explicitly described as "direct," when a relationship between a first element and a second element is described in the above disclosure, the relationship may be a direct relationship where no other intervening elements exist between the first element and the second element, or an indirect relationship where one or more intervening elements (spatially or functionally) exist between the first element and the second element. As used herein, the phrase "at least one of A, B, and C" should be interpreted as meaning the logic of (A OR B OR C) using a non-exclusive logical OR, and should not be interpreted as meaning "at least one of A, at least one of B, and at least one of C."

[0071]

[0080] However, although terms such as first, second, and third may be used herein to describe various converters, circuits, groups, ESMs, reactors, and / or other elements, these converters, circuits, groups, ESMs, reactors, and / or other elements should not be limited by these terms unless otherwise specified. These terms may be used merely to distinguish one converter, circuit, group, ESM, reactor, and / or element from another converter, circuit, group, ESM, reactor, and / or element. For example, terms such as "first," "second," and other numerical terms, when used herein, may not imply an order or sequence unless clearly indicated by context. Thus, a first converter, circuit, group, ESM, reactor, and / or element described herein may be referred to as a second converter, circuit, group, ESM, reactor, and / or element without departing from the teachings of the example embodiments.

[0072]

[0081] In a diagram, the direction of the arrow, indicated by the arrowhead, generally illustrates the flow of information (e.g., data or instructions) of interest to the diagram. For example, when element A and element B exchange various information, but information sent from element A to element B is relevant to the diagram, the arrow may point from element A to element B. This one-way arrow does not mean that other information is not sent from element B to element A. Furthermore, for information sent from element A to element B, element B may send a request for the information or an acknowledgment of receipt of the information to element A.

[0073]

[0082] In this application, including the definitions below, the term "module" or "controller" may be interchangeable with the term "circuitry." The term "module" may refer to, be a part of, or include an application specific integrated circuit (ASIC), a digital, analog, or mixed analog / digital discrete circuit, a digital, analog, or mixed analog / digital integrated circuit, a combinational logic circuit, a field programmable gate array (FPGA), a processor circuit (shared, dedicated, or group) that executes code, a memory circuit (shared, dedicated, or group) that stores code to be executed by the processor circuit, other suitable hardware components that provide the described functionality, or a combination of some or all of the above, such as a system on a chip.

[0074]

[0083] A module may include one or more interface circuits. In some examples, the interface circuit may include a wired or wireless interface connected to a local area network (LAN), the Internet, a wide area network (WAN), or a combination thereof. The functionality of any given module of the present disclosure may be distributed among multiple modules connected via interface circuits. For example, multiple modules may enable load balancing. In a further example, a server module (also known as a remote or cloud) may perform some functions on behalf of a client module.

[0075]

[0084] The term code, as used above, may include software, firmware, and / or microcode, and may represent programs, routines, functions, classes, data structures, and / or objects. The term shared processor circuit encompasses one processor circuit that executes some or all code from multiple modules. The term group processor circuit encompasses a processor circuit that executes some or all code from one or more modules in combination with additional processor circuits. The term multiple processor circuits encompasses multiple processor circuits on separate dies, multiple processor circuits on a single die, multiple cores on a single processor circuit, multiple threads on a single processor circuit, or any combination thereof. The term shared memory circuit encompasses one memory circuit that stores some or all code from multiple modules. The term group memory circuit encompasses a memory circuit that stores some or all code from one or more modules in combination with additional memory.

[0076]

[0085] The term memory circuit is a subset of the term computer-readable medium. As used herein, the term computer-readable medium does not encompass transient electrical or electromagnetic signals propagating through a medium (e.g., on a carrier wave); therefore, the term computer-readable medium may be considered tangible and non-transitory. Non-limiting examples of non-transitory tangible computer-readable media are non-volatile memory circuits (e.g., flash memory circuits, erasable programmable read-only memory circuits, or mask read-only memory circuits), volatile memory circuits (e.g., static random access memory circuits or dynamic random access memory circuits), magnetic storage media (e.g., analog or digital magnetic tape or hard disk drives), and optical storage media (e.g., CDs, DVDs, or Blu-ray discs).

[0077]

[0086] The apparatus and methods described in this application may be implemented in part or entirely by a special-purpose computer generated by configuring a general-purpose computer to perform one or more specific functions embodied in a computer program. The functional blocks, flowchart components, and other elements described above function as software specifications that can be translated into a computer program by the routine work of a skilled engineer or programmer.

[0078]

[0087] A computer program includes processor-executable instructions stored on at least one non-transitory, tangible computer-readable medium. A computer program may further include or rely on stored data. A computer program may encompass a basic input / output system (BIOS) that interacts with hardware in a special-purpose computer, device drivers that interact with specific devices in a special-purpose computer, one or more operating systems, user applications, background services, background applications, etc.

[0079]

[0088] A computer program may include (i) a written language to be parsed, such as HTML (Hypertext Markup Language), XML (Extensible Markup Language), or JSON (JavaScript Object Notation); (ii) assembly code; (iii) object code generated from source code by a compiler; (iv) source code for execution by an interpreter; (v) source code for compilation and execution by a runtime compiler; etc. By way of example only, the source code may be written using the syntax of languages ​​including C, C++, C#, Objective-C, Swift, Haskell, Go, SQL, R, Lisp, Java®, Fortran, Perl, Pascal, Curl, OCaml, Javascript®, HTML5 (Hypertext Markup Language Fifth Version), Ada, ASP (Active Server Pages), PHP (PHP: Hypertext Preprocessor), Scala, Eiffel, Smalltalk, Erlang, Ruby, Flash®, Visual Basic®, Lua, MATLAB®, SIMULINK®, and Python®.

Claims

1. an input configured to receive power from a power source; an output configured to output power to one or more high power periodic loads; 1. A resistor fuse circuit, comprising: one or more resistors; one or more fuses connected together in series with the one or more resistors; a resistor fuse circuit comprising: an electrically controlled safety switching device comprising a coil and contacts, the contacts being connected in parallel with the resistor fuse circuit; An overload protection module, the overload protection module comprising: enabling the hybrid fault protection circuit by energizing the coil and closing the contacts to supply a load current from the input to the output through the contacts when there is no fault downstream of the hybrid fault protection circuit; Detecting an anomaly downstream of the hybrid fault protection circuit; in response to detecting the fault, opening the contacts to cause fault current to flow through the one or more fuses rather than across the contacts; an overload protection module configured to A hybrid fault protection circuit comprising:

2. The hybrid fault protection circuit of claim 1 , wherein the one or more resistors comprise a plurality of resistors.

3. 2. The hybrid fault protection circuit of claim 1, wherein the impedance of the resistor fuse circuit is higher than the impedance of the contacts when closed, such that a majority of the current flowing from the input to the output flows through the contacts when closed.

4. 2. The hybrid fault protection circuit of claim 1, wherein the impedance of the resistor-fuse circuit is higher than the impedance of the contacts when closed, such that 95% or more of the current flowing from the input to the output flows through the contacts when closed.

5. The hybrid fault protection circuit of claim 1 , wherein the electrically controlled safety switching device is realized as a circuit breaker, a contactor, or a high-speed mechanical switch.

6. The hybrid fault protection circuit of claim 1 , wherein the one or more fuses comprise a plurality of fuses connected in parallel.

7. the hybrid fault protection circuit further comprising one or more current sensors configured to detect at least one of a power supply current from the input and a contact current through the contact; 2. The hybrid fault protection circuit of claim 1, wherein the overload protection module is configured to detect the fault based on the at least one of the power supply current from the input and the contact current through the contact.

8. 2. The hybrid fault protection circuit of claim 1, wherein a blow time of the one or more fuses is greater than at least one of: i) the time for the contacts to move farther apart than a minimum restriking distance (ARD); and ii) the time for the overload protection module to cause the contacts to move farther apart than the minimum ARD.

9. 2. The hybrid fault protection circuit of claim 1, wherein the overload protection module is configured to determine whether to operate in a limp mode after detecting the fault and opening the contacts beyond the minimum ARD, and to reclose the contacts in response to determining to operate in the limp mode.

10. a direct current (DC) link including a plurality of DC link rails; 2. The hybrid fault protection circuit according to claim 1, wherein an output of the hybrid fault protection circuit is connected to the DC link; one or more high power periodic loads receiving power from the DC link; A machine equipped with:

11. The machine of claim 10 further comprising one or more power sources that provide power to the DC link.

12. The machine of claim 11 , wherein the one or more power sources comprise at least one of an engine and a power storage module.

13. 11. The machine of claim 10, further comprising a trolley pantograph connected to the input and configured to receive power from an overhead contact wire.

14. The hybrid fault protection circuit according to claim 1; one or more substations that supply power to the input of the hybrid fault protection circuit via an overhead contact wire; A power supply system comprising:

15. The hybrid fault protection circuit according to claim 1; the power supply that supplies power to the hybrid fault protection circuit; the one or more high power periodic loads receiving power from the output of the hybrid fault protection circuit; A vehicle equipped with:

16. 16. The vehicle of claim 15, wherein the power source is an engine, a power storage module, or a trolley pantograph.

17. 1. A method of operating a hybrid fault protection circuit, said method comprising: enabling the hybrid fault protection circuit, the hybrid fault protection circuit comprising an electrically controlled safety switching device connected in parallel with a resistor fuse circuit, the electrically controlled safety switching device comprising a coil and contacts, the resistor fuse circuit comprising one or more resistors connected together in series with one or more fuses, the enabling of the hybrid fault protection circuit including energizing the coil to close the contacts and supply load current through the contacts to one or more high power periodic loads; sensing at least one parameter of the hybrid fault protection circuit; comparing the at least one parameter to at least one threshold to detect a fault downstream of the hybrid fault protection circuit; in response to detecting the fault, opening the contacts of the electrically controlled safety switching device to cause fault current to flow through the one or more fuses rather than across the contacts; A method comprising:

18. the at least one parameter includes at least one of a power supply current and a current through the contacts; 18. The method of claim 17.

19. The method of claim 17 , wherein the at least one threshold comprises a current threshold and an energy threshold.

20. detecting a power supply current supplied to the hybrid fault protection circuit; determining whether the one or more fuses are blown based on the detected power supply current; operating in a limp mode, including closing the contacts to allow current to flow from an input of the hybrid fault protection circuit to an output of the hybrid fault protection circuit, in response to detecting that the one or more fuses are blown; 20. The method of claim 17, further comprising:

Images