Arc detection based on frequency analysis

Abstract

Embodiments of the present disclosure generally relate to arc detection based on frequency analysis. In some examples, a device includes at least one input node configured to receive a signal indicating a current flowing through a conductor to a load. The device also includes circuitry configured to determine a first amplitude of the received signal within a first frequency range by applying a first bandpass filter to the received signal. The circuitry is further configured to determine a second amplitude of the received signal within a second frequency range by applying a second bandpass filter to the received signal. The processing circuitry is further configured to determine that an arc has occurred on the conductor based on the first amplitude and the second amplitude.

Description

Technical Field

[0001] The present disclosure relates to power electronics equipment. Background Art

[0002] When an arc occurs in an electrical distribution system, it generates very high temperatures, which can melt wire insulation. Arcing can cause short circuits between adjacent wires, rapidly draining the battery. Arcing can also create a fire hazard, which is particularly dangerous for lithium-ion batteries.

[0003] As the potential difference between two points increases, arcing becomes more likely. For example, typical automotive systems use a 12-volt power system, but some vehicles now use 48-volt power subsystems. Due to the higher voltage and, implicitly, the higher maximum sustainment distance, arcs are more likely to occur and sustain in 48-volt systems than in 12-volt systems. As a result, arc prevention and detection in 48-volt systems are more critical than in 12-volt systems.

[0004] A 48-volt power system is preferable to a 12-volt system because it uses lower current. Conductors carrying lower current can be designed with smaller cross-sections. To prevent arcing, 48-volt systems can be designed with thicker plastic insulation around the conductors. Consequently, a 48-volt system uses less metal and more plastic. When plastic is significantly cheaper than metal, designing a power system that can operate at 48 volts is cost-effective, as the cost savings from using less metal more than offset the increased insulation costs. Furthermore, using plastic instead of metal can reduce weight. Summary of the Invention

[0005] This disclosure describes a technique for determining whether an arc has occurred on a conductor based on frequency analysis. A device may receive a signal indicating current flowing through the conductor to a load. The device applies a first passband filter to the received signal to determine a first amplitude within a first frequency range. The device also applies a second passband filter to the received signal to determine a second amplitude within a second frequency range. The device may use the first determined amplitude and the second determined amplitude to determine whether an arc has occurred.

[0006] In some examples, a device includes at least one input node configured to receive a signal indicative of a current flowing through a conductor to a load. The device also includes circuitry configured to determine a first amplitude of the received signal within a first frequency range by applying a first bandpass filter to the received signal. The circuitry is further configured to determine a second amplitude of the received signal within a second frequency range by applying a second bandpass filter to the received signal. The circuitry is further configured to determine that an arc has occurred on the conductor based on the first amplitude and the second amplitude.

[0007] In some examples, a method includes receiving, by at least one node of a device, a signal indicating a current flowing through a conductor to a load. The method also includes determining, by processing circuitry of the device, a first amplitude of the received signal within a first frequency range by applying a first bandpass filter to the received signal. The method also includes determining, by the processing circuitry, a second amplitude of the received signal within a second frequency range by applying a second bandpass filter to the received signal. The method includes determining, by the processing circuitry, that an arc has occurred on the conductor based on the first amplitude and the second amplitude.

[0008] In some examples, a device includes a computer-readable medium having executable instructions stored thereon, the instructions configured to be executed by processing circuitry to cause the processing circuitry to determine a first amplitude of a signal within a first frequency range by applying a first bandpass filter to the signal, wherein the signal is indicative of a current flowing through a conductor to a load. The instructions are further configured to cause the processing circuitry to determine a second amplitude of the signal within a second frequency range by applying a second bandpass filter to the signal, wherein the signal is indicative of a current flowing through the conductor to the load. The instructions are further configured to cause the processing circuitry to determine that an arc has occurred on the conductor based on the first amplitude and the second amplitude.

[0009] The details of one or more examples are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 is a conceptual block diagram of a device configured to determine that an electrical arc has occurred on a conductor, according to some examples of the present disclosure.

[0011] Figure 2 is a conceptual block diagram of a system including a load and an engine according to some examples of the present disclosure.

[0012] Figure 3 is a conceptual block diagram of a device including an analog-to-digital converter and processing circuitry according to some examples of the present disclosure.

[0013] Figures 4A-4E is a graph illustrating exemplary bandpass filters according to some examples of the present disclosure.

[0014] Figure 5 is a conceptual block diagram of a system including a gate driver and a microcontroller according to some examples of the present disclosure.

[0015] Figure 6 is a flow chart illustrating an example technique for determining that an arc has occurred on a conductor, according to some examples of the present disclosure.

[0016] Figure 7 and Figure 8 are conceptual block diagrams and circuit diagrams of systems including current sensing at a load according to some examples of the present disclosure. DETAILED DESCRIPTION

[0017] Figure 1 1 is a conceptual block diagram of a device 100 configured to determine that an electrical arc 175 has occurred on a conductor 170, according to some examples of the present disclosure. A system 140 includes the device 100, a power source 150, a power switch 160, a conductor 170, and a load 190. The system 140 may be part of an automotive system, an aviation system, a power generation system, a power distribution system, a power electronics system, and / or any other system in which an electrical arc 175 may occur on a conductor 170. The system 140 may be referred to as a "boardnet" (e.g., an on-board network).

[0018] Power supply 150 provides electrical power to power switch 160 and / or load 190. Power supply 150 can include a battery, a generator, a solar panel, and / or any other source of electrical power. Power supply 150 and reference node 195 can form the positive and negative rails of a differential bus. In some examples, power supply 150 includes a car battery configured to provide 48 volts of power.

[0019] Power switch 160 can be configured to conduct electricity between power supply 150 and load 190 based on a driver signal received at node 162. When power switch 160 is on, power supply 150 can provide electrical power to conductor 170 and load 190. When power switch 160 is off, power supply 150 is electrically disconnected from conductor 170 and load 190. However, when power switch 160 is off, a non-zero leakage current can flow through power switch 160. Power switch 160 can include, but is not limited to, any type of field effect transistor (FET), bipolar junction transistor (BJT), insulated gate bipolar transistor (IGBT), high electron mobility transistor (HEMT), and / or other voltage-controlled element. Power switch 160 can include n-type transistors and / or p-type transistors. Power switch 160 can include elements such as silicon, silicon carbide, and / or gallium nitride. In some examples, power switch 160 includes a freewheeling diode connected in parallel with the transistor to prevent reverse breakdown of the transistor. System 140 need not include power switch 160 in all examples, as power source 150 may be connected to conductor 170 and load 190 without a power switch.

[0020] The conductor 170 allows the transmission of electrical power between the power supply 150 and the load 190. The conductor 170 can include a metal wire, a metal layer, a trace in a circuit board, solder and / or any other conductive element. The conductor 170 can include materials such as copper, gold, silver, aluminum, lead, tin and / or any other conductive material. In some embodiments, the conductor 170 directly connects the power supply 150 and the load 190 without the power switch 160. The conductor 170 can include a wiring harness for carrying multiple wires, such as a first wire for connecting the power supply 150 and the conductor 190 and a second wire serving as a return path for a reference node 195.

[0021] The load 190 may include a resistive load, a capacitive load, and / or an inductive load. Examples of inductive loads may include actuators, motors, and pumps used in one or more systems of heating, air conditioning, water supply, fans, or other systems that include inductive loads. Examples of capacitive loads may include lighting elements (such as xenon arc lamps). In other examples, the load may be a combination of resistive, inductive, and capacitive loads.

[0022] Arc 175 can occur on conductor 170, generating very high temperatures that can damage nearby components (such as wire insulation). Arc 175 can also cause an electrical short circuit between adjacent wires. Arc 175 can deplete the energy stored in power supply 150 and can pose a fire hazard. Arc 175 can persist for a distance of up to thirteen millimeters, which is much longer than the interruption distance of a standard relay. Unless system 140 includes a device for detecting arc 175, arc 175 may not be detected. However, some techniques for detecting arc 175 increase the weight, cost, and points of failure of system 140.

[0023] According to the techniques of the present disclosure, post-processing module 130 uses bandpass filter 110 to analyze the spectrum of the received signal. Bandpass filter 110 can be used as a single filter with a passband that can be moved along the spectrum, or as multiple filters with a constant passband. Bandpass filter 110 selectively filters the current flowing to load 190. Peak detector 120 can also be adaptive, receiving (multiple) filtered signals and can be configured to detect peaks and threshold crossings. Post-processing module 130 can be configured to determine whether an arc 175 has occurred based on the crossing of a threshold within a specific time and the ratio between the detected peaks. In some examples, post-processing module 130 is configured to analyze the current flowing to a single load 170, rather than multiple currents flowing to multiple loads, to avoid frequency overlap from other loads. Post-processing module 130 looks for the frequency signature of arc 175 in the signal received at node 102.

[0024] Device 100 can include a node 102 for receiving a signal indicating a current flowing through conductor 170 to load 190. Node 102 receives a signal from a sensing element 180, which can include a shunt resistor, a current sensing transistor, a magnetoresistive element, and / or any other current sensor. In some examples, node 102 includes two or more nodes that receive a differential signal, such as a voltage across a shunt resistor.

[0025] The device 100 may also include a bandpass filter 110 for filtering the signal received at the node 102. Each of the bandpass filters 110 may include a different frequency range. When applied to the received signal, one of the bandpass filters 110 generates an output signal representing the amplitude of the received signal within the corresponding frequency range. A peak detector 120 may detect a peak or threshold crossing of the output signal generated by each of the bandpass filters 110. The peak detector 120 may be configured to output an indication of the amplitude of each signal received within the frequency range of the bandpass filter 110.

[0026] Post-processing module 130 can determine that arc 175 has occurred on conductor 170 based on a first amplitude of the received signal within a first frequency range and a second amplitude of the received signal within a second frequency range. Post-processing module 130 can determine that arc 175 has occurred by determining that the first amplitude and the second amplitude exhibit or match a predetermined mathematical relationship. In some examples, the predefined mathematical relationship can correspond to characteristics associated with electromagnetic noise generated by arc 175. In some examples, the arc current can be random in nature, having a broad frequency spectrum with varying peaks and uncorrelated frequencies that change over time. Post-processing module 130 can be configured to perform a frequency analysis to determine the frequency spectrum and then determine whether arc 175 has occurred toward load 190.

[0027] Although the present disclosure describes the device 100 as determining whether the arc 175 has "occurred," the device 100 can be configured to determine whether the arc 175 is currently occurring and / or has previously occurred. The arc 175 can occur for a very short period of time, on the order of microseconds or milliseconds. The determination by the device 100 as to whether the arc 175 is occurring can take on the order of milliseconds. Thus, by the time the device 100 completes the determination, the arc 175 may be occurring, or the arc 175 may have ended and may no longer occur. Although the arc 175 is shown occurring on the conductor 170 between the power switch 160 and the sensing element 180, the arc 175 may occur at other locations, such as on the conductor 170 between the sensing element 180 and the load 190, on the conductor 170 near the load 190, and / or on the conductor 170 near the power switch 160.

[0028] Using a bandpass filter 110 to filter the signal at the sensing element 180 to determine that an arc 175 has occurred allows for the use of a less expensive "dumb" load 190. The dumb load may not have intelligent current and voltage sensing or a transceiver for transmitting current and voltage values ​​back to the device 100 or a microcontroller. Compared to a system using another technology for detecting an arc, the system 140 may also require less wire, which makes the system 140 cheaper, lighter (e.g., less metal but more plastic), and have fewer points of failure. For example, compared to a system with a load that transmits voltage and current information back to the device 100 or a microcontroller, the system 140 can use less copper.

[0029] Additionally, the system 140 may include a microcontroller (MCU) that has lower performance specifications (eg, less power), is smaller, less expensive, and has fewer pins. Figure 1 (not shown in FIG. 1 ). Because device 100 performs arc detection, the microcontroller can be configured to not constantly monitor parameters of load 190. The techniques of this disclosure can allow for decentralized evaluation and simplification of wiring harnesses in system 140. Thus, device 100 can provide substantial value to system 140.

[0030] Figure 2 is a conceptual block diagram of a system 240 including a load 290 and an engine 220 according to some examples of the present disclosure. The system 240 is Figure 1 An example of system 100 is shown. Device 200 is configured to receive a signal indicative of a current flowing through conductor 270 to load 290 via sensing element 280. Figure 2 In the example shown, the device 200 is further configured to control the operation of the power switch 260 by turning the power switch 260 on and off to connect and disconnect the power source 250 from the load 290. For example, the device 200 may include a microcontroller for generating a control signal (e.g., a pulse width modulated signal) for the power switch 260. Additionally or alternatively, the device 200 may include a gate driver for generating a drive signal and transmitting the drive signal to a control terminal of the power switch 260. The device 200 may include a high-side gate driver for the power switch 260 (such as a battery switch, a load connect-disconnect, and an electronic fuse).

[0031] In some examples, device 200 may be part of a fuse replacement product. In some examples, device 200 may be a standalone unit that can be used with other electrical devices connected to a load, and in other examples, device 200 may comprise a component of a larger electrical device. In various examples, there may be a separate power switch and / or conductor for each load in the system. Thus, there may be one of devices 200 for each load and each power switch in the system. While device 200 may be particularly useful for 48-volt automotive systems, device 200 may also be used in 12-volt or 24-volt automotive systems, as well as non-automotive power systems.

[0032] System 240 includes an engine 220 and a load 290, each of which can emit electromagnetic noise. The electromagnetic noise emitted by engine 220 can have a unique signature or spectrum, and the electromagnetic noise emitted by load 290 can have a unique signature or spectrum that is different from the unique signature or spectrum generated by engine 220. During normal operation, engine 220 and / or load 290 can generate a well-defined spectrum in current consumption, with high peaks at the fundamental frequency and subsequent harmonics. Device 200 can detect power-on and power-off by detecting a single large change in current consumption. Device 200 can also detect ringing after power-off because the oscillation frequency is based on predefined inductive, capacitive, and resistive parasitics, generating a damped (almost) single-frequency oscillation.

[0033] Device 200 can be configured to determine the level of electromagnetic noise injected by load 290 and / or engine 220 in the current through conductor 270. Device 200 can use a bandpass filter in a frequency range that includes the noise injected by load 290 and / or engine 220. Device 200 can apply the bandpass filter to the signal received by device 200 from sensing element 280 to determine the level of noise injected by load 290 and / or engine 220. By determining the amplitude of the noise injected by load 290 and / or engine 220, device 200 can better determine whether an arc 275 has occurred.

[0034] Figure 3 3 is a conceptual block diagram of a device 300 according to some examples of the present disclosure, including an analog-to-digital converter (ADC) 304 and processing circuitry 312. Device 300 is a digital implementation of device 100, where processing circuitry 312 includes digital logic for determining the amplitude of a received signal. In some examples, the device may include analog circuitry (a bandpass filter and a peak detector) for determining the amplitude of a received signal.

[0035] exist Figure 3In the example shown, device 300 receives a differential signal at two nodes. The differential signal (e.g., the difference between the two signals) can indicate a voltage across a shunt resistor 380, which is indicative of a current flowing through a conductor 370. The differential signal is an example of a signal received by device 100 from sensing element 180 at node 102. Shunt resistor 380 is an example of a sensing element from which device 300 receives a signal indicating a current flowing through conductor 370. Similar to system 100, system 300 includes a power supply 350 for delivering electrical power to a load 390 via a power switch 360, which is operated based on a signal received at node 362.

[0036] The pre-filter 302 can be configured to low-pass filter the received signal. The pre-filter 302 can define a low-pass input filter for the ADC 304, for example, to remove high-frequency noise from the received signal. The pre-filter 302 can have a cutoff frequency that is higher than the frequency range of the at least two band-pass filters 310. The pre-filter 302 can also have a cutoff frequency that is higher than the sampling rate of the ADC 304. In some examples, the device 300 is configured to use the pre-filter 302 as part of an integrated high-pass filter and low-pass filter. The ADC 304 receives the pre-filtered signal, or in some examples, the unfiltered signal, and converts the signal into a digital value. The ADC 304 generates a series of digital values ​​over time, the digital values ​​representing the amplitude of the signal over time.

[0037] Processing circuitry 312 may be part of the digital core of device 300. Processing circuitry 312 may apply bandpass filter 310 to the series of digital values ​​output by ADC 304. Figure 3In the example shown, each of bandpass filters 310 is a digital filter implemented by processing circuitry 312. For example, device 300 may include a set of instructions that, when executed, cause processing circuitry 312 to apply each of bandpass filters 310 to a series of digital values ​​to determine the amplitude within a respective frequency range. In some examples, processing circuitry 312 may apply one or more bandpass filters 310 by applying a lowpass filter (e.g., prefilter 302) and a highpass filter to the received signal or series of digital values. Device 300 may use prefilter 302 as a single lowpass filter (e.g., an analog filter) and each of bandpass filters 310 as a highpass filter, either as a separate highpass filter or as a single, shifted highpass filter. As a result, each of the highpass filters may share a single lowpass filter. Alternatively, device 300 may use prefilter 302 as multiple separate lowpass filters. Thus, in some embodiments, processing circuitry 312 may be configured to use bandpass filters 310 as highpass filters.

[0038] Processing circuitry 312 may use peak detector 320 to determine the amplitude of the output of each of bandpass filters 310. Peak detector 320 may determine the peak amplitude of a signal or a series of digital values. Additionally or alternatively, peak detector 320 may determine whether the amplitude crosses, exceeds, or is greater than a threshold. In some examples, peak detector 320 may include a root mean square (RMS) detector, a quasi-RMS detector, and / or an average detector.

[0039] The post-processing module 330 is configured to determine whether an arc 375 has occurred based on the outputs of the bandpass filter 310 and the peak detector 320. For example, the post-processing module 330 can determine that an arc 375 has occurred by determining that the amplitudes output by the bandpass filter 310 and the peak detector 320 exhibit a predetermined mathematical relationship. The post-processing module 330 can calculate ratios or relationships of amplitudes or peak values ​​at different frequencies and then check whether the ratios match the predetermined mathematical relationship. The predetermined mathematical relationship can include an inverse frequency relationship or any other relationship in which the amplitude decreases as the frequency increases. The arc 375 can generate electromagnetic noise having characteristics that are proportional to 1 / f, 1 / (f^N), or any other relationship, where f is the frequency and N is any constant. Thus, the device 300 can be configured to: measure the current through the conductor 370; digitize the signal using the ADC 304; bandpass filter the digitized output; and confirm the occurrence of the arc 375 if the amplitude detected in different filtering windows (e.g., frequency ranges) shows a pattern of a 1 / f noise signal (e.g., an inverse frequency relationship).

[0040] The post-processing module 330 can be configured to determine parameters and characteristics of the arc 375 based on the received signal and analyzing the amplitude output by the bandpass filter 310. For example, the post-processing module 330 can determine the duration and / or magnitude of the arc 375. Magnitude refers to the voltage drop caused by the arc 375, the current flowing through the arc 375, or the distance spanned by the arc 375. The post-processing module 330 can also determine the type of arc 375 (e.g., parallel or serial) and / or the cause of the arc 375. In some examples, the post-processing module 330 is configured to distinguish the cause of the arc 375 from other causes.

[0041] Figures 4A-4E is a graph illustrating exemplary bandpass filters according to some examples of the present disclosure. Figures 4A-4E The vertical axis of the graph shown in represents noise density, which may be expressed in units of volts squared divided by hertz. Figures 4A-4E The horizontal axis of the graph shown in represents frequency, which can be expressed in Hertz. The axis of the graph uses a logarithmic scale to display frequencies between less than one Hertz and greater than one hundred thousand Hertz.

[0042] Figure 4A An example with two bandpass filters is shown. The device can use two bandpass filters 410A and 420A where the parameters of the mathematical relationship (e.g., slope) are known and where there are no other interferences or components that generate noise. The slope 400A represents a predetermined mathematical relationship that is a spectral blueprint of the arc. Figure 4A In the example shown, bandpass filter 410A covers a frequency range of one hertz to ten hertz, and bandpass filter 420A covers a frequency range of one hundred hertz and one thousand hertz. The device can determine the ratio of the amplitude of the signal within each frequency range.

[0043] The frequency range of the bandpass filters 410A and 420A can be selected or limited to not overlap with the fundamental frequency injected by the load or other nearby components (such as, an engine). The frequency range of the bandpass filters 410A and 420A can be selected to not overlap with the switching frequency of the power switch. The frequency range of the bandpass filters 410A and 420A can be selected to be below the level at which steady-state noise swamps the electromagnetic noise generated by the arc. The steady-state noise can be white noise with approximately equal amplitude at all frequencies. Therefore, at high frequencies where the noise generated by the arc is lower, the steady-state noise can overwhelm the noise generated by the arc. Above ten hertz, twenty hertz, or thirty hertz, the signal generated by the arc may be indistinguishable from noise generated by other sources.

[0044] Figure 4B and Figure 4CAn example with three bandpass filters is shown. If there is no interference, the device can use a third bandpass filter in which at least one parameter of a predetermined mathematical relationship is unknown to confirm that an arc has occurred. The device can use the amplitudes detected by the two (or more) filters to determine the unknown parameter(s). In some examples, the device uses two filters to determine the unknown parameter(s) and the mathematical relationship. The device can then confirm the mathematical relationship by determining whether the third amplitude from the third bandpass filter matches the previously calculated mathematical relationship within an allowable tolerance. Alternatively, the device can use a third bandpass filter in which the parameters of the predetermined mathematical relationship are known to determine the level of steady-state noise. The device can select a frequency range greater than 5 kHz, 10 kHz, 20 kHz, 100 kHz, or 200 kHz to detect the level of steady-state noise because, at high frequencies, the noise may be mostly steady-state rather than generated by the arc or load. For example, the center frequency of the bandpass filter can be set to 200 kHz to measure the level of steady-state noise.

[0045] In some examples, bandpass filters 410B, 420B, and 430B can be implemented as separate filters. In contrast, bandpass filters 410C, 412C, and 414C can be implemented as a single mobile filter whose frequency range and center frequency can be varied. For example, a device can use a single mobile bandpass filter as bandpass filter 410C at one time, as bandpass filter 412C at a second time, and as bandpass filter 414C at a third time. The device can move the single bandpass filter along the spectral distribution of the noise generated by the arc. In some examples, the device can apply multiple bandpass filters using at least one mobile bandpass filter and at least one fixed bandpass filter, where the fixed filter is separate from the mobile filter. Thus, the device can use at least one fixed bandpass filter with a fixed frequency range and at least one mobile bandpass filter that can be applied across multiple frequency ranges. Mobile filters can be useful in determining the level of background noise or steady-state noise. Fixed bandpass filters have a fixed frequency range that does not move, so the device cannot apply a fixed bandpass filter across multiple frequency ranges.

[0046] Bandpass filters 410B, 420B, 430B can be easier to design, build, and operate than a single mobile bandpass filter that can be used as bandpass filters 410C, 412C, 414C. However, bandpass filters 410B, 420B, 430B can take up more chip space than a single mobile bandpass filter. A single mobile bandpass filter may be more difficult to build and operate, but a single mobile bandpass filter takes up less chip space than bandpass filters 410B, 420B, 430B. Either a separate bandpass filter or a single mobile bandpass filter can be implemented as an analog filter, a digital filter, a software filter, and / or a hardware filter.

[0047] Figure 4D An example with four bandpass filters is shown. The device can use a fourth bandpass filter, in which at least one parameter of the predetermined mathematical relationship is unknown, to determine the level of steady-state noise in the high-frequency range. Alternatively, the device can use a fourth bandpass filter, in which the parameters of the predetermined mathematical relationship are known, to determine the level of noise injected by a load or another component. The center frequency of the fourth bandpass filter can be selected to be near a high peak generated by a component connected to or adjacent to the device.

[0048] Figure 4E An example with five bandpass filters is shown. The device may use a fifth bandpass filter, in which at least one parameter of the predetermined mathematical relationship is unknown, to perform a rationality check by determining the level of noise injected by the load or another component. The number, order, and purpose of the filters described herein may be modified. For example, the device may use a third bandpass filter to determine the noise injected by the load, or the device may use a fifth bandpass filter to determine that an arc has occurred. Additionally, in some embodiments, the device may use more than five bandpass filters. The device may also use more than one bandpass filter for any of the purposes described herein, such as three or more bandpass filters to confirm the occurrence of an arc, two or more bandpass filters to detect steady-state noise, or two or more bandpass filters to detect noise injected by the load. Additional bandpass filters may be used to tune to specific types of arc detection.

[0049] Figure 5 5 is a conceptual block diagram of a system 540 including a gate driver 564 and a microcontroller 544 according to some examples of the present disclosure. System 540 also includes an integrated circuit 500, a direct current / direct current (DC / DC) converter 542, a power supply 550, a power switch 560, a conductor 570, a shunt resistor 580, and a load 590. Integrated circuit 500 includes a power management unit (PMU) 504, a detection circuit device 510, digital logic 530, and a gate driver 564. Integrated circuit 500 is Figure 1-Figure 3Examples of device 100, device 200, and device 300 are shown. Integrated circuit 500 may provide high voltage capability and high circuit density for digital integration.

[0050] The PMU 504 receives power from the power supply 550 and provides power to the detection circuitry 510, the digital logic 530, and the gate driver 564. The PMU 504 may include a power converter to generate power for each of the components of the integrated circuit 500. The integrated circuit 500 may include a charge pump and / or a boost converter as part of the PMU 504 or the gate driver 564 to generate a voltage higher than the power supply 550. The gate driver 564 may use the higher voltage level to drive the power switch 560 to turn the power switch 560 on and off, thereby connecting and disconnecting the power supply 550 and the load 590.

[0051] The detection circuit device 510 may include an ADC that measures and digitizes the voltage drop across a shunt resistor 580, which may be connected in series in the current supply path of the load 590 between the power supply 550 and the power switch 560. The shunt resistor 580 should be arranged so that it is not affected by loads other than the load 590. For example, if the shunt resistor 580 is arranged between the power distribution point of the power supply 550 (e.g., after the battery switch) and the drain of the power switch 560. The digital logic 530 may be part of the digital core of the integrated circuit 500 and may analyze the information provided by the inspection circuit device 510 (e.g., the ADC and / or the filter) by performing spectrum analysis.

[0052] The digital logic 530 also has a communication interface with a microcontroller 544, which receives a power supply from the DC / DC converter 542. The digital logic 530 can communicate or report the detection of an arc to the microcontroller 544. The digital logic 530 can be configured to transmit the type of arc and other determined parameters or characteristics of the arc to the microcontroller 544, such as the length of time and magnitude of the arc.

[0053] although Figure 5 Although described as a digital implementation, an analog implementation is also possible. Analog filters occupy more chip area than digital filters, especially for low-frequency filtering. In addition, analog filters are more difficult to configure than digital filters, especially for implementations that include a single moving filter. Configuring a digital filter may involve changing the coefficients of the filter, as opposed to changing the inductance or capacitance of an analog capacitor. In addition, a digital implementation allows the digitized current information generated by the digital logic 530 to be used for other purposes in the integrated circuit 500, such as overcurrent protection.

[0054] During operation of system 540 and integrated circuit 500, gate driver 564 turns on power switch 560. An ADC in detection circuitry 510 measures the current flowing through shunt resistor 580 and digitizes this information. Digital logic 530 performs filtering and peak detection. Based on the peak detection determination and by examining the ratio between filtered amplitudes, digital logic 530 determines whether an arc has occurred on conductor 570 (e.g., within conductor 570 held by a wiring harness). Digital logic 530 determines that an arc has occurred based on the fundamental frequency, harmonics, the amplitudes of the fundamental frequency and harmonics, and previously analyzed history. If an arc is detected by digital logic 530, integrated circuit 500 may determine whether to immediately turn off power switch 560 and notify microcontroller 544. Additionally or alternatively, digital logic 530 may limit the current on conductor 570 and notify microcontroller 544, or digital logic 530 may simply notify microcontroller 544 and wait for microcontroller 544 to determine whether to turn off power switch 560 and disconnect load 590.

[0055] Other implementations of the detection mechanism are possible that do not involve full frequency analysis. For example, if the frequency spectrum of the load 590 is known and the expected ripple frequencies after shutdown are also known, the digital logic 530 and / or the detection circuit device 510 can apply a filter to eliminate these frequencies from the analyzed signal. The digital logic 530 and / or the detection circuit device 510 can then use a peak detector to analyze the remaining signal. The integrated circuit 500 can implement the filter in the analog domain or the digital domain. Unfortunately, this technique may impose limitations on the types of loads that can be driven by the power switch 560. This technique also assumes additional knowledge of the occurrence frequencies. However, this technique can also result in a smaller and simpler integrated circuit 500.

[0056] Figure 6 is a flow chart illustrating an example technique for determining that an arc has occurred on a conductor according to some examples of the present disclosure. Figure 1 The system 140 shown in FIG. Figure 6 Although other components may exemplify similar techniques.

[0057] exist Figure 6 In the example of FIG. 1 , node 102 receives a signal (600) indicating a current flowing through conductor 170 to load 190. Device 100 receives a signal at node 102 from sensing element 180, which may include a shunt resistor or series resistor and / or capacitor, a current mirror, a current sensing transistor, a magnetoresistive sensor, and / or any other current sensor. In some examples, the received signal is a differential signal representing a voltage across sensing element 180.

[0058] exist Figure 6 In the example of FIG. 1 , the device 100 determines a first amplitude of a received signal within a first frequency range by applying a first bandpass filter of the bandpass filters 110 (602). The device 100 also determines a second amplitude of the received signal within a second frequency range by applying a second bandpass filter of the bandpass filters 110 (604). The device 100 can use the bandpass filters 110 as individual filters or as a single mobile filter that can be independently used as the first bandpass filter and the second bandpass filter. The device 100 can also apply more than two bandpass filters 110 to determine whether an arc 175 has occurred, to determine parameters of a mathematical relationship between amplitudes, to detect a level of steady-state noise in the system 100, and / or to detect a level of noise generated by the load 190.

[0059] exist Figure 6 In the example of FIG. 5 , post-processing module 130 determines that arc 175 has occurred on conductor 170 based on the first amplitude and the second amplitude ( 606 ). Post-processing module 130 can be configured to determine a ratio of the first amplitude and the second amplitude. Post-processing module 130 can detect that arc 175 has occurred in response to determining that the ratio of the amplitudes exhibits a predetermined mathematical relationship (e.g., a characteristic of arc 175).

[0060] Figure 7 and Figure 8 1 is a conceptual block diagram and circuit diagram of systems 740 and 840 including current sensing at a load according to some examples of the present disclosure. Although systems 740 and 840 are shown as 48 volt systems, systems 740 and 840 can also be configured to use different voltage levels, such as twelve volts or twenty-four volts. System 740 includes a gate driver 700, a microcontroller 744, a battery 750, a power switch 760, a conductor 770, a wiring harness 772, a shunt resistor 780, and a load 790. System 840 includes a gate driver 800, a microcontroller 844, a battery 850, a power switch 860, a conductor 870, wiring harnesses 872 and 874, a shunt resistor 880, and a load 890.

[0061] In 48V systems such as systems 740 and 840, arc detection can be performed by simultaneously measuring and comparing the current and voltage at the output of batteries 750 and 850 and the current and voltage at the input of loads 790 and 890. System 740 is an example of instantaneous readout of the voltage and current at the output of battery 750 and the input of load 790. This configuration ensures simultaneous readout, which is important because the magnitude of the current flowing through an arc varies greatly over time. The configuration of system 740 uses additional wires in harness 772 and smart load 790, which can send current and voltage information back to the analyzing microcontroller 744. This configuration increases the weight, cost, and failure points of system 740.

[0062] In the example of system 740, the voltage and current are physically sent back to the microcontroller 744. The microcontroller 744 can trigger the comparison quickly and easily because the gate driver 700 and the load 790 send all parameters directly to the ADC of the microcontroller 744. If the system 740 has many loads, the wiring harness can be complex and more prone to short circuits, disconnections, and synchronization issues.

[0063] System 840 is an example of multiplexed readout via a communication bus in wiring harness 874. This configuration has the advantage of fewer wires in wiring harness 872, but system 840 uses smart loads 890 with bus communication capabilities. Due to time multiplexing, system 840 may also experience information transmission delays, which can lead to erroneous assessments. Therefore, system 840 may be less accurate and still incur the added cost of smart loads 890.

[0064] In the example of system 840, the voltage and current are sent back to the microcontroller 844 via a bus, such as a controller area network (CAN) bus. The use of separate wiring harnesses 872 and 874 means that wiring is relatively simple. However, due to the potential delay between the load 890 and the microcontroller 844, the microcontroller 844 may have difficulty synchronizing between the battery 850 and the load 890. Although the load 890 can trigger the acquisition via the CAN bus, the microcontroller 844 can handle the synchronization using direct conversion of the power supply parameters. Transmitting the parameters back via the CAN bus can cause delays in the transmission of the load parameters.

[0065] Another approach is to measure the current draw in the conductor and apply a Fourier transform to determine the signal's spectral components. The arc's spectral footprint can reveal the behavior of 1 / f noise. However, applying a Fourier transform requires significant computing power, which is only available in expensive, high-end microcontrollers. Fourier analysis can require high input bandwidth and computational power in a microcontroller. This approach may not be cost-effective for systems with numerous 48V loads.

[0066] The smart loads 790 and 890 can measure and transmit the current and voltage at the load back to the gate drivers 700 and 800 and / or the microprocessors 744 and 844. The gate drivers 700 and 800 can measure the voltage and current sent to the loads 790 and 890. The microcontrollers 744 and 844 can process and compare all information sent from the gate drivers 700 and 800 and the loads 790 and 890. If there is no arc, the voltage level of the batteries 750 and 850 is equal to the voltage level received by the loads 790 and 890, and the current generated by the batteries 750 and 850 is equal to the current received by the loads 790 and 890.

[0067] A first example of an arc that can occur in wiring harnesses 772 and 872 is a parallel arc between a live conductor and a reference ground. The conductor's shield may be grounded, so an arc can occur between the conductor and its shield. This type of arc can be caused by poor conductor insulation. For this type of arc, the voltage level of batteries 750 and 850 may be equal to the voltage level received by loads 790 and 890, but due to current losses to the parallel arc, the current drawn by batteries 750 and 850 may be greater than the current received by loads 790 and 890. Given that arc behavior can be unpredictable, microcontroller 744 should compare parameters simultaneously.

[0068] A second example of an arc that can occur in wiring harnesses 772 and 872 is a series arc between two energized conductors. This type of arc can be caused by a broken cable or poor contact. With this type of arc, the current generated by batteries 750 and 850 can be equal to the current received by loads 790 and 890, but due to the voltage drop across the series arc, the voltage level of batteries 750 and 850 can be greater than the voltage level received by loads 790 and 890. However, if, for example, the impedance of the arc changes over time, the current comparison between the battery and the load may become unbalanced.

[0069] The following numbered examples illustrate one or more aspects of the disclosure.

[0070] Example 1. A device includes at least one input node configured to receive a signal indicative of a current flowing through a conductor to a load. The device also includes circuitry configured to determine a first amplitude of the received signal within a first frequency range by applying a first bandpass filter to the received signal. The circuitry is further configured to determine a second amplitude of the received signal within a second frequency range by applying a second bandpass filter to the received signal. The circuitry is further configured to determine that an arc has occurred on the conductor based on the first amplitude and the second amplitude.

[0071] EXAMPLE 2. The apparatus of Example 1, wherein the circuit arrangement is configured to determine that an arc has occurred on the conductor by determining that the first amplitude and the second amplitude exhibit a predetermined mathematical relationship.

[0072] Example 3. The apparatus of Examples 1-2 or any combination thereof, wherein the circuit arrangement is configured to determine that arcing has occurred on the conductor by determining that a ratio of the first amplitude and the second amplitude exhibits an inverse frequency relationship.

[0073] Example 4. The apparatus of Examples 1-3 or any combination thereof, wherein the circuit arrangement is configured to apply the first bandpass filter and the second bandpass filter by applying a single shifted bandpass filter.

[0074] Example 5. The apparatus of examples 1-4 or any combination thereof, wherein the single moving bandpass filter is configured as a first bandpass filter at a first time and as a second bandpass filter at a second time.

[0075] Example 6. The apparatus of Examples 1-5 or any combination thereof, wherein the circuit arrangement is configured to determine a third amplitude of the received signal within a third frequency range by applying a third bandpass filter to the received signal.

[0076] Example 7. The apparatus of Examples 1-6 or any combination thereof, wherein the circuit arrangement is configured to confirm that an arc has occurred on the conductor based on the third amplitude when at least one parameter of the mathematical relationship for the arc is unknown.

[0077] Example 8. The apparatus of Examples 1-7 or any combination thereof, wherein the circuitry is configured to determine at least one parameter of the mathematical relationship.

[0078] Example 9. The apparatus of Examples 1-8 or any combination thereof, wherein the circuitry is configured to determine at least one parameter of the mathematical relationship based on at least one of the magnitudes.

[0079] Example 10. The apparatus of Examples 1-9 or any combination thereof, wherein the circuitry is configured to determine a fourth amplitude of the received signal within a fourth frequency range by applying a fourth bandpass filter to the received signal.

[0080] Example 11. The apparatus of Examples 1-10 or any combination thereof, wherein the circuit arrangement is configured to determine the level of the steady-state noise based on the fourth amplitude.

[0081] Example 12. The apparatus of Examples 1-11 or any combination thereof, wherein the fourth frequency range is higher than the first frequency range, the second frequency range, and the third frequency range.

[0082] Example 13. The apparatus of Examples 1-12 or any combination thereof, wherein the circuit arrangement is configured to determine a fifth amplitude of the received signal within a fifth frequency range by applying a fifth bandpass filter to the received signal.

[0083] Example 14. The apparatus of Examples 1-13 or any combination thereof, wherein the circuit arrangement is configured to determine a level of noise injected by the load based on the fifth amplitude.

[0084] Example 15. The apparatus of Examples 1-14 or any combination thereof, wherein the circuit arrangement is configured to determine a third amplitude of the received signal within a third frequency range by applying a third bandpass filter to the received signal.

[0085] Example 16. The apparatus of Examples 1-15 or any combination thereof, wherein the circuit arrangement is configured to determine the level of the steady-state noise based on the third amplitude when parameters of the mathematical relationship for the arc are unknown.

[0086] Example 17. The apparatus of Examples 1-16 or any combination thereof, wherein the circuitry is configured to determine a fourth amplitude of the received signal within a fourth frequency range by applying a fourth bandpass filter to the received signal.

[0087] Example 18. The apparatus of Examples 1-17 or any combination thereof, wherein the circuit arrangement is configured to determine a level of noise injected by the load based on the fourth amplitude.

[0088] Example 19. The apparatus of Examples 1-18 or any combination thereof, wherein the circuit arrangement is configured to determine the level of the steady-state noise based on at least one of the amplitudes.

[0089] Example 20. The apparatus of Examples 1-19 or any combination thereof, wherein the circuit arrangement is configured to determine a level of noise injected by the load based on the fifth amplitude.

[0090] Example 21. The apparatus of Examples 1-20 or any combination thereof, wherein the circuit arrangement is configured to apply the first bandpass filter by independently applying a first lowpass filter and a first highpass filter to the received signal.

[0091] Example 22. The apparatus of Examples 1-21 or any combination thereof, wherein the circuit arrangement is configured to apply the second bandpass filter by independently applying a second lowpass filter and a second highpass filter to the received signal.

[0092] Example 23. An apparatus according to Examples 1-22 or any combination thereof, wherein the circuit device is configured to determine the first amplitude by applying a first bandpass filter to generate a first filtered signal and applying a first RMS detector, a first quasi-RMS detector, or a first average detector to the first filtered signal.

[0093] Example 24. An apparatus according to Examples 1-23 or any combination thereof, wherein the circuit device is configured to determine the second amplitude by applying a second bandpass filter to generate a second filtered signal and applying a second RMS detector, a second quasi-RMS detector, or a second average detector to the second filtered signal.

[0094] Example 25. The device of Examples 1-24 or any combination thereof, further comprising an ADC configured to convert the received signal into a series of digital values.

[0095] Example 26. The apparatus of Examples 1-25 or any combination thereof, wherein the circuit arrangement is configured to determine the first amplitude within the first frequency range by applying a first bandpass filter to the series of digital values.

[0096] Example 27. The apparatus of Examples 1-26 or any combination thereof, wherein the circuit arrangement is configured to determine the second amplitude within the second frequency range by applying a second bandpass filter to the series of digital values.

[0097] Example 28. The device of Examples 1-27 or any combination thereof, wherein the signal is indicative of a current through the power switch and through the conductor to the load.

[0098] Example 29A. The device of Examples 1-28 or any combination thereof, further comprising a gate driver configured to deliver a drive signal to the power switch to turn the power switch on or off.

[0099] Example 29B. The apparatus of Examples 1-29A or any combination thereof, wherein the circuit arrangement is configured to use at least one of the bandpass filters as a fixed bandpass filter having a fixed frequency range.

[0100] Example 29C. The apparatus of Examples 1-29B or any combination thereof, wherein the circuit arrangement is configured to use at least one of the bandpass filters as a moving bandpass filter, the moving bandpass filter being configurable to have different frequency ranges at different times.

[0101] Example 29D. The apparatus of Examples 1-29C or any combination thereof, wherein the circuit arrangement is configured to apply both a fixed bandpass filter and a moving bandpass filter to the received signal.

[0102] Example 30. A method includes receiving, by at least one node of a device, a signal indicating a current flowing through a conductor to a load. The method also includes determining, by processing circuitry of the device, a first amplitude of the received signal within a first frequency range by applying a first bandpass filter to the received signal. The method also includes determining, by the processing circuitry, a second amplitude of the received signal within a second frequency range by applying a second bandpass filter to the received signal. The method includes determining, by the processing circuitry, that an arc has occurred on the conductor based on the first amplitude and the second amplitude.

[0103] EXAMPLE 31. The method of Example 30, wherein determining that arcing has occurred on the conductor comprises determining that the first amplitude and the second amplitude exhibit a predetermined mathematical relationship.

[0104] Example 32. The method of Examples 30-31 or any combination thereof, wherein determining that arcing has occurred on the conductor comprises determining that a ratio of the first amplitude and the second amplitude exhibits an inverse frequency relationship.

[0105] Example 33. The method of Examples 30-32 or any combination thereof, wherein applying the first bandpass filter and the second bandpass filter comprises applying a single shifted bandpass filter.

[0106] Example 34. The method of Examples 30-33 or any combination thereof, wherein the single moving bandpass filter is configured as a first bandpass filter at a first time and as a second bandpass filter at a second time.

[0107] Example 35. The method of Examples 30-34 or any combination thereof, wherein determining a third amplitude of the received signal within a third frequency range comprises applying a third bandpass filter to the received signal.

[0108] EXAMPLE 36. The method of Examples 30-35 or any combination thereof, further comprising confirming that arcing has occurred on the conductor based on the third amplitude when at least one parameter of the mathematical relationship for the arc is unknown.

[0109] Example 37. The method of Examples 30-36 or any combination thereof, further comprising determining at least one parameter of the mathematical relationship.

[0110] Example 38. The method of Examples 30-37 or any combination thereof, further comprising determining at least one parameter of the mathematical relationship based on the at least one magnitude.

[0111] Example 39. The method of Examples 30-38 or any combination thereof, further comprising determining a fourth amplitude of the received signal within a fourth frequency range by applying a fourth bandpass filter to the received signal.

[0112] Example 40. The method of Examples 30-39 or any combination thereof, further comprising determining a level of steady-state noise based on the fourth amplitude.

[0113] Example 41. The method of Examples 30-40 or any combination thereof, wherein the fourth frequency range is higher than the first frequency range, the second frequency range, and the third frequency range.

[0114] Example 42. The method of Examples 30-41 or any combination thereof, further comprising determining a fifth amplitude of the received signal within a fifth frequency range by applying a fifth bandpass filter to the received signal.

[0115] Example 43. The method of Examples 30-42 or any combination thereof, further comprising determining a level of noise injected by the load based on the fifth amplitude.

[0116] Example 44. The method of Examples 30-43 or any combination thereof, further comprising determining a third amplitude of the received signal within a third frequency range by applying a third bandpass filter to the received signal.

[0117] Example 45. The method of Examples 30-44 or any combination thereof, further comprising determining a level of steady-state noise based on the third amplitude when parameters of the mathematical relationship for the arc are known.

[0118] Example 46. The method of Examples 30-45 or any combination thereof, further comprising determining a fourth amplitude of the received signal within a fourth frequency range by applying a fourth bandpass filter to the received signal.

[0119] Example 47. The method of Examples 30-46 or any combination thereof, further comprising determining a level of noise injected by the load based on the fourth amplitude.

[0120] Example 48. The method of Examples 30-47 or any combination thereof, further comprising determining a level of steady-state noise based on at least one amplitude.

[0121] Example 49. The method of Examples 30-48 or any combination thereof, further comprising determining a level of noise injected by the load based on the fifth amplitude.

[0122] Example 50. The method of Examples 30-49 or any combination thereof, wherein applying the first bandpass filter comprises independently applying a first lowpass filter and a first highpass filter to the received signal.

[0123] Example 51. The method of Examples 30-50 or any combination thereof, wherein applying a second bandpass filter comprises independently applying a second lowpass filter and a second highpass filter to the received signal.

[0124] Example 52. A method according to Examples 30-51 or any combination thereof, wherein determining the first amplitude includes applying a first bandpass filter to generate a first filtered signal and applying a first RMS detector, a first quasi-RMS detector, or a first average detector to the first filtered signal.

[0125] Example 53. A method according to Examples 30-52 or any combination thereof, wherein determining the second amplitude includes applying a second bandpass filter to generate a second filtered signal and applying a second RMS detector, a second quasi-RMS detector, or a second average detector to the second filtered signal.

[0126] Example 54. The method of Examples 30-53 or any combination thereof, further comprising converting the received signal into a series of digital values.

[0127] Example 55. The method of Examples 30-54 or any combination thereof, wherein determining the first amplitude within the first frequency range comprises applying a first bandpass filter to the series of digital values.

[0128] Example 56. The method of Examples 30-55 or any combination thereof, wherein determining a second amplitude within a second frequency range comprises applying a second bandpass filter to the series of digital values.

[0129] Example 57. The method of Examples 30-56 or any combination thereof, wherein the signal indicates a current through the power switch and through the conductor to the load.

[0130] Example 58. The method of Examples 30-57 or any combination thereof, further comprising delivering a drive signal to a power switch to turn the power switch on or off.

[0131] Example 59. The method of Examples 1-59 or any combination thereof, wherein the circuit arrangement is configured to use at least one of the bandpass filters as a fixed bandpass filter having a fixed frequency range.

[0132] Example 60. The method of Examples 1-60 or any combination thereof, wherein the circuit arrangement is configured to use at least one of the bandpass filters as a moving bandpass filter, the moving bandpass filter being configurable to have different frequency ranges at different times.

[0133] Example 61. The method of Examples 1-61 or any combination thereof, wherein the circuit arrangement is configured to apply both a fixed bandpass filter and a moving bandpass filter to the received signal.

[0134] Example 62. An apparatus comprising a computer-readable medium having executable instructions stored thereon, the instructions configured to be executable by processing circuitry to cause the processing circuitry to determine a first amplitude of a signal within a first frequency range by applying a first bandpass filter to the signal, wherein the signal is indicative of a current flowing through a conductor to a load. The instructions are further configured to cause the processing circuitry to determine a second amplitude of the signal within a second frequency range by applying a second bandpass filter to the signal, wherein the signal is indicative of a current flowing through the conductor to the load. The instructions are further configured to cause the processing circuitry to determine that an arc has occurred on the conductor based on the first amplitude and the second amplitude.

[0135] Example 63. The apparatus according to Example 62, wherein the instructions are configured to cause the processing circuitry to perform the method according to Examples 30-61 or any combination thereof.

[0136] Example 64. A system comprising means for receiving a signal indicative of current flowing through a conductor to a load. The system further comprises means for determining a first amplitude of the received signal within a first frequency range by applying a first bandpass filter to the received signal. The system further comprises means for determining a second amplitude of the received signal within a second frequency range by applying a second bandpass filter to the received signal. The system comprises means for determining that an arc has occurred on the conductor based on the first amplitude and the second amplitude.

[0137] Example 65. The system of Example 64, further comprising means for performing the method of Examples 30-61 or any combination thereof.

[0138] The present disclosure attributes functionality to devices 100, 200, and 300 and integrated circuit 500. Devices 100, 200, and 300 and integrated circuit 500 may include one or more processors. Devices 100, 200, and 300 and integrated circuit 500 may include any combination of integrated circuit devices, discrete logic circuit devices, analog circuit devices (such as one or more microprocessors), digital signal processors (DSPs), application specific integrated circuits (ASICs), and / or field programmable gate arrays (FPGAs). In some examples, devices 100, 200, and 300 and integrated circuit 500 may include multiple components, such as one or more microprocessors, one or more DSPs, one or more ASICs, or one or more FPGAs, as well as any combination of other discrete logic circuit devices or integrated logic circuit devices and / or analog circuit devices.

[0139] The techniques described in this disclosure may also be implemented or encoded in an article of manufacture that includes a non-transitory computer-readable storage medium, such as devices 100, 200, and 300, and integrated circuit 500. Example non-transitory computer-readable media may include RAM, ROM, programmable ROM (PROM), erasable programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), flash memory, a hard disk, magnetic media, optical media, or any other computer-readable storage device or tangible computer-readable medium. The term "non-transitory" may indicate that the storage medium is not embodied in a carrier wave or propagating signal. In some examples, a non-transitory storage medium may store data that may change over time (e.g., in RAM or cache).

[0140] Various examples of the present disclosure have been described. Any combination of the described systems, operations, or functions is contemplated. These and other examples are within the scope of the following claims.

Claims

1. A device for detecting an arc, comprising: at least one input node configured to receive a signal indicative of current through the conductor to the load; as well as A circuit arrangement configured to: determining a first amplitude of the received signal within a first frequency range by applying at least a first bandpass filter to the received signal; determining a second amplitude of the received signal within a second frequency range by applying at least a second bandpass filter to the received signal; determining a third amplitude of the received signal within a third frequency range by applying at least a third bandpass filter to the received signal, wherein the third amplitude is equal at all frequencies within the third frequency range; determining a level of steady-state noise based on the third amplitude; and determining that an arc has occurred on the conductor based on the first amplitude and the second amplitude; The circuit arrangement is configured to determine that the arc has occurred on the conductor by at least determining that the first amplitude and the second amplitude exhibit a predetermined mathematical relationship. 2 . The apparatus of claim 1 , wherein the circuit arrangement is configured to determine that the arc has occurred on the conductor by at least determining that a ratio of the first amplitude and the second amplitude exhibits an inverse frequency relationship.

3. The device according to claim 1, wherein the circuit arrangement is configured to apply the first bandpass filter and the second bandpass filter by applying at least a single shifted bandpass filter, and Wherein the single mobile bandpass filter is configured as the first bandpass filter at a first time and is configured as the second bandpass filter at a second time.

4. The device according to claim 3, wherein the circuit arrangement is configured to determine the third amplitude by applying at least a fixed bandpass filter to the received signal, and The third frequency range includes a fixed frequency range.

5. The apparatus of claim 1 , wherein the circuit arrangement is configured to: determining a fourth amplitude of the received signal within a fourth frequency range by applying at least a fourth bandpass filter to the received signal; and When at least one parameter of the mathematical relationship for the arc is unknown, confirming that the arc has occurred on the conductor is based on the fourth amplitude. The apparatus of claim 5 , wherein the circuitry is configured to determine the at least one parameter of the mathematical relationship. The apparatus of claim 1 , wherein the third frequency range is higher than the first frequency range and the second frequency range.

8. The apparatus of claim 5 , wherein the circuit arrangement is configured to: determining a fifth amplitude of the received signal within a fifth frequency range by applying at least a fifth bandpass filter to the received signal; and A level of noise injected by the load is determined based on the fifth amplitude.

9. The apparatus of claim 1 , wherein the circuit arrangement is configured to: When the parameters of the mathematical relationship for the arc are known, the level of the steady-state noise is determined based on the third amplitude.

10. The apparatus of claim 9, wherein the circuit arrangement is configured to: determining a fourth amplitude of the received signal within a fourth frequency range by applying at least a fourth bandpass filter to the received signal; and A level of noise injected by the load is determined based on the fourth amplitude.

11. The device according to claim 1, wherein the circuit arrangement is configured to apply the first bandpass filter by independently applying at least a first lowpass filter and a first highpass filter to the received signal, and Wherein the circuit arrangement is configured to apply the second band pass filter by independently applying at least a second low pass filter and a second high pass filter to the received signal.

12. The apparatus of claim 11, wherein the circuit arrangement is configured to apply the first and second low-pass filters by applying at least a single low-pass filter to the received signal.

13. The apparatus according to claim 1, wherein the circuit arrangement is configured to determine the first amplitude by applying at least the first bandpass filter to generate a first filtered signal and applying a first root mean square (RMS) detector, a first quasi-RMS detector or a first average detector to the first filtered signal, and Wherein the circuit arrangement is configured to determine the second amplitude by applying at least the second bandpass filter to generate a second filtered signal and applying a second RMS detector, a second quasi-RMS detector or a second average detector to the second filtered signal.

14. The apparatus of claim 1 , further comprising an analog-to-digital converter configured to convert the received signal into a series of digital values; wherein the circuitry comprises processing circuitry configured to: determining the first amplitude within the first frequency range by applying at least the first bandpass filter to the series of digital values; and The second amplitude within the second frequency range is determined by applying at least the second bandpass filter to the series of digital values.

15. A method for detecting an arc, comprising: receiving, by at least one node of the device, a signal indicative of current flowing through the conductor to the load; determining, by processing circuitry of the apparatus, a first amplitude of the received signal within a first frequency range by applying at least a first bandpass filter to the received signal; determining, by the processing circuitry, a second amplitude of the received signal within a second frequency range by applying at least a second bandpass filter to the received signal; determining, by the processing circuitry, a third amplitude of the received signal within a third frequency range by applying at least a third bandpass filter to the received signal, wherein the third amplitude is equal at all frequencies within the third frequency range; determining, by the processing circuitry, a level of steady-state noise based on the third amplitude; as well as determining, by the processing circuitry, that an arc has occurred on the conductor based on the first amplitude and the second amplitude; Wherein determining that the arc has occurred on the conductor includes determining that the first amplitude and the second amplitude exhibit a predetermined mathematical relationship.

16. The method of claim 15, wherein determining that the arc has occurred comprises determining that a ratio of the first amplitude and the second amplitude exhibits an inverse frequency mathematical relationship.

17. The method according to claim 15, further comprising: determining a fourth amplitude of the received signal within a fourth frequency range by applying at least a fourth bandpass filter to the received signal; as well as When at least one parameter of the mathematical relationship for the arc is unknown, confirming that the arc has occurred on the conductor is based on the fourth amplitude.

18. The method according to claim 15, further comprising: determining the level of the steady-state noise based on the third amplitude when parameters of the mathematical relationship for the arc are known; determining a fourth amplitude of the received signal within a fourth frequency range by applying at least a fourth bandpass filter to the received signal; as well as A level of noise injected by the load is determined based on the fourth amplitude.

19. A device for detecting an electric arc, comprising: at least one input node configured to receive a signal indicative of current through the conductor to the load; as well as A circuit arrangement configured to: determining a first amplitude of the received signal within a first frequency range by applying at least a first bandpass filter to the received signal; determining a second amplitude of the received signal within a second frequency range by applying at least a second bandpass filter to the received signal; determining a third amplitude of the received signal within a third frequency range by applying at least a third bandpass filter to the received signal, wherein the third amplitude is equal at all frequencies within the third frequency range; determining a noise level injected by the load based on the third amplitude; as well as determining, based on the first amplitude and the second amplitude, that an arc has occurred on the conductor; The circuit arrangement is configured to determine that the arc has occurred on the conductor by at least determining that the first amplitude and the second amplitude exhibit a predetermined mathematical relationship.

20. The apparatus according to claim 19, wherein the circuit arrangement is configured to apply the first bandpass filter and the second bandpass filter by applying at least a single shifted bandpass filter; and Wherein the single mobile bandpass filter is configured as the first bandpass filter at a first time and as the second bandpass filter at a second time.

21. The apparatus according to claim 19, wherein the circuit is configured to determine the third amplitude by applying at least a fixed bandpass filter to the received signal; and The third frequency range includes a fixed frequency range.

22. The apparatus of claim 19, wherein the circuit is configured to: determining a fourth amplitude of the received signal within a fourth frequency range by applying at least a fourth bandpass filter to the received signal; and When at least one parameter of the mathematical relationship for the arc is unknown, confirming that the arc has occurred on the conductor is based on the fourth amplitude.

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