DC fault management power system

Abstract

Fault management power methods and systems are provided that include a source, a downstream component, and a power cable for delivering electrical energy from the source to the downstream component, the electrical energy including electrical pulses or DC current / voltage and electrical pulses. The cable is isolated from noise or signals upstream and downstream using low pass filters disposed upstream and downstream of the power cable. The method and system may use an impedance sensor tank to measure electrical activity on the cable; detecting electrical disturbances on the cable based on measurements from the sensor when the pulses or DC current / voltage and pulses are provided to the cable, the electrical disturbances corresponding to the occurrence of faults or other faults due to body contact with the cable; and in response to detecting the occurrence of the fault, interrupting the supply of electrical energy to the cable via the upstream switch.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of and priority to Indian Provisional Patent Application Serial No. 202311041096 filed on June 16, 2023. The disclosure of the above-mentioned prior patent application is incorporated herein by reference in its entirety. Technical Field

[0003] The present disclosure relates generally to fault protection in power supplies and, more particularly, to methods and systems for isolating power cables to detect conditions to limit the energy provided to a fault, including touch-safe levels. Background Art

[0004] Power over Ethernet (PoE) generally refers to the use of conductor pairs (usually twisted pair or Ethernet cables) to send both power and data. Therefore, devices that can be powered by PoE are called powered devices (PDs) and generally do not require a separate source adapter to provide power. Examples of powered devices include VoIP phones, high-definition cameras (pan-zoom-tilt cameras), wireless access points (WAPs), network routers, and other devices. As demand for so-called "smart building" services grows, the number of powered devices is expected to grow exponentially.

[0005] PFC (power over fiber cable) is similar to PoE in that power and data are provided over a single cable, thus eliminating (or at least reducing) the need for separate source adapters to power devices. With PFC, data is sent over the fiber, while power is typically provided through a conductive sheath (usually copper) surrounding the fiber. Due to the lossless or near-lossless nature of fiber, a typical PFC cable can send data over longer distances than a typical PoE cable.

[0006] In applications such as PoE and PFC, power is typically injected into the cable at a voltage of 44 to 57Vdc and typically 48Vdc. This voltage level allows power to be efficiently transmitted along the cable while still being low enough to be safe for the end user. The original industry standard for PoE powered equipment (PSE) allowed a maximum power level of 30W. The new PoE standard or PoE++ (IEEE802.3Bt) allows power levels up to 100W. Standards that take into account higher power levels are under development.

[0007] As power levels continue to increase in applications such as PoE and PFC, a method is needed to ensure that the energy delivered into the fault is limited. Summary of the invention

[0008] According to an embodiment, a fault management power system is provided. The power system may include a source, a power cable, and a downstream component, such as a load-side component. The power cable may include at least one conductive wire for transmitting electrical energy. The source may be connected to the upstream of the power cable and may supply electrical energy to the power cable, including electrical pulses or DC current / voltage together with the electrical pulses. The source may include: an upstream low-pass filter connected between the power source and the power cable, for isolating the power cable from upstream noise or signals; a sensor, including an impedance sensor tank circuit, for measuring electrical activity associated with the electrical pulses on the power cable; at least one upstream switch arranged upstream of the power cable, and at least one controller. At least one controller may be configured to: when the electrical pulses or DC current / voltage together with the electrical pulses are provided to the power cable, based on measurements from the impedance sensor tank circuit, detect electrical disturbances on the power cable corresponding to the occurrence of a fault caused by human contact with the cable (or its conductive component), and in response to detecting the occurrence of the fault, interrupt the supply of electrical energy to the power cable via at least one upstream switch. The downstream component may be connected to the downstream of the power cable and may receive electrical energy supplied through the power cable. The downstream components may include a downstream low pass filter for isolating the power cable from downstream noise or signals.

[0009] In various embodiments, the impedance sensor tank circuit can be configured to sense impedance changes on a power cable or leakage current on the cable. The sensor can include an impedance sensor with an RC component and a pi filter with an LC component. The capacitor in the impedance sensor and the inductor in the pi filter can form a tank circuit to amplify the fault signal on the cable.

[0010] In various embodiments, the at least one upstream switch may include a switch that is turned on and off to generate the electrical pulses. The at least one upstream switch may include a solid-state switch or a crowbar circuit.

[0011] In various embodiments, the source may further include an upstream power converter, located upstream of the upstream low-pass filter, for converting electrical energy supplied from the power source. The downstream component may further include a downstream power converter, located downstream of the downstream low-pass filter, for converting electrical energy received from the power cable and providing the converted electrical energy to the downstream load.

[0012] In various embodiments, at least one switch may include: a first upstream switch; a second upstream switch including a solid-state switch; and a third upstream switch including a crowbar circuit. In response to detecting the occurrence of a fault, the second upstream switch may be operated to interrupt the supply of a DC current / voltage to the power cable, and the third upstream switch may be operated to interrupt the supply of a DC current / voltage to the power cable by short-circuiting the upstream source in response to detecting the occurrence of a fault. When the number of detected fault occurrences satisfies the count, the first upstream switch may be operated to interrupt the supply of a DC current / voltage to the power cable and stop the power supply operation. Optionally, a fourth switch located at the source output between the impedance sensor and the power cable may be disconnected to prevent the DC current / voltage from being applied to the power cable.

[0013] The at least one controller may also be configured to: control the generation of an electrical pulse during a startup phase, generating the pulse by momentarily closing a solid-state switch (e.g., S2) before allowing the supply of DC current / voltage. When the electrical pulse is supplied to the power cable, the at least one controller may detect the occurrence of a fault based on measurements from the impedance sensor tank circuit, and in response to the detection of the occurrence of a fault, not close S2, prevent the DC voltage from being applied to the circuit, and optionally operate a third switch.

[0014] The at least one controller may be further configured to: operate the second upstream switch to provide a DC current / voltage from the source to the power cable when the occurrence of a fault is not detected during the startup phase. When the DC current / voltage is provided to the power cable along with the electrical pulses, the at least one controller may detect the occurrence of a fault based on a measurement of electrical activity from the impedance sensor tank circuit, and in response to detecting the occurrence of the fault, interrupt the supply of the DC current / voltage and the electrical pulses to the power cable using the second and third upstream switches.

[0015] In various embodiments, the cable may include a twisted 2-wire cable or a twisted 3-wire cable, the upstream and downstream low pass filters may include π filters, and / or power line communication may be performed over the power cable.

[0016] In various embodiments, the fault may include a fault caused by line-to-line human body contact on the power cable, or a fault caused by line-to-ground human body contact on the power cable.

[0017] In various embodiments, the source may be configured to provide electrical pulses during a startup phase and then allow a DC current voltage or a DC current / voltage to be provided along with the electrical pulses during steady state operation.

[0018] According to an embodiment, a method for implementing fault management power according to the fault management power system described herein is provided.

[0019] According to another embodiment, a method and system are provided to calibrate a detection system for detecting a condition on an electrical system. The electrical system includes a source circuit configured to be electrically connected to or disconnected from a downstream circuit to a closed circuit state or an open circuit state, respectively. The method includes:

[0020] when a first system voltage for calibration is applied to the source circuit, measuring a reference voltage across the source circuit in an open circuit state for a predetermined period of time using a sensor, a plurality of measurements of the reference voltage being made by the sensor over time and stored in a memory;

[0021] measuring a voltage across the source circuit in an open circuit state for a predetermined period of time using a sensor when a second system voltage different from the first system voltage is applied to the source circuit,

[0022] scaling a reference voltage from a plurality of measurements of the reference voltage relative to the second system voltage based on a ratio between the second system voltage and the first system voltage to provide a scaled reference voltage;

[0023] Calculating a difference between the scaled reference voltage and a voltage across the source circuit measured by the sensor at the second system voltage;

[0024] Calculating a change in voltage over time between a previous voltage and a voltage measured by the sensor over a predetermined period of time at a second system voltage;

[0025] Comparing the difference and voltage changes over time to respective thresholds; and

[0026] • In response to the comparison, determining whether a condition on the electrical system has occurred.

[0027] In various embodiments, the plurality of measurements of the threshold and reference values ​​are scaled according to a ratio between the second system voltage and the first system voltage.

[0028] In various embodiments, in an electrical system, a source circuit includes a low pass filter and is connected to a power cable, which in turn is connected to a downstream electrical component that includes at least a low pass filter. The low pass filters of the source circuit and the downstream electrical component prevent upstream and downstream noise or signals on the power cable. A sensor is located between the low pass filter of the source circuit and the power cable to sense a voltage across the power cable. Conditions include faults caused by a body contacting the power cable or other types of faults.

[0029] In various embodiments, the method and system may further include: detecting a circuit configuration type of the downstream circuit; and configuring the threshold value according to the detected configuration of the downstream circuit. The type of circuit configuration includes a single load or multiple loads.

[0030] In various embodiments, the scaling operation may include: calculating a ratio of the second system voltage to the first system voltage; and calculating a scaled reference voltage equal to the calculated ratio multiplied by the reference voltage from the plurality of measurements of the reference voltage.

[0031] In various embodiments, the sensor includes an RC circuit or an impedance sensor, and the reference voltage and the current voltage are measurements of the voltage across a capacitor of the RC circuit or impedance sensor.

[0032] In various embodiments, the source circuit includes a plurality of switches, having a first switch configured to electrically connect or disconnect the source circuit to a system input providing a system voltage, and a second switch configured to electrically connect or disconnect the source circuit to a downstream circuit. In addition, the method and system may also include: in response to the detection of the condition, interrupting the power supply to the downstream circuit via one or more of the plurality of switches.

[0033] In various embodiments, in the method and system, scaling operations and calculation operations are performed according to the following equations:

[0034] Ratio = Vs / Vrated;

[0035] Vs = Vin / (R1+R2) / R2;

[0036] Vref[i]=Ratio*Vref_Table[i];

[0037] Delta = Vref[i] - VC[i]; and

[0038] Slope=(VC[i-1]–VC[i]) / Tdelta,

[0039] in:

[0040] Vrated is the first system voltage of the source circuit used for calibration;

[0041] Vs is a second system voltage corresponding to the applied system voltage of the source circuit,

[0042] V in is a scaled second system voltage corresponding to the applied (operating) system voltage of the source circuit,

[0043] V_Ref2, V_Ref3, V_Ref4, V_Ref5,…, V_Refn),

[0044] Tdelta is the step time or time interval,

[0045] Delta is the difference,

[0046] Slope is the change in voltage over time, and

[0047] i=1 to n.

[0048] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as disclosed or claimed. The claims should be given their full scope, including equivalents. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The description of various example embodiments is explained in conjunction with the accompanying drawings.

[0050] Figure 1A An example of a block diagram of a fault management power system using power cable isolation technology according to an embodiment of the present disclosure is shown.

[0051] Figure 1B A simplified circuit schematic diagram showing an example of a circuit for measuring faults on a power cable is shown in accordance with an embodiment of the present disclosure.

[0052] Figure 1C Waveforms from a SPICE model are shown, showing variations of the waveforms and simplification of the circuit to identify and illustrate the main components for detecting faults on a power cable.

[0053] Figure 1D The switch according to an embodiment of the present disclosure is shown in the open position. Figure 1A Example of a fault management source (or transmitter) of an electric power system.

[0054] Figure 2 An example process for operating a fault-managed power system or component thereof employing power cable isolation techniques according to an embodiment of the present disclosure is shown.

[0055] Figure 3A An example process of operating a fault-managed power system or component thereof employing power cable isolation technology with detection pulse measurement during switch-on according to an embodiment of the present disclosure is shown.

[0056] Figure 3B The generation of a voltage reference table (eg, Vr ef _Table).

[0057] Figure 4A An example process for operating a fault-managed power system or component thereof employing power cable isolation techniques according to an embodiment of the present disclosure is shown.

[0058] Figure 4B An example calibration process of a detection system for an electrical or power system according to an embodiment of the present disclosure is shown.

[0059] Figure 5A An example of a graph showing the variation of voltage sensed across a conductor (eg, a power cable) over time in relation to a human body model is shown in accordance with an embodiment of the present disclosure.

[0060] Figure 5B An example of a graph showing the variation of voltage sensed across a conductor (eg, a power cable) over time in relation to a human body model is shown in accordance with an embodiment of the present disclosure.

[0061] Figure 6 An example of a point-to-point architecture is shown in which a fault management power system may be employed according to an embodiment of the present disclosure.

[0062] Figure 7 An example of a radial architecture is shown in which a fault management power system may be employed according to an embodiment of the present disclosure.

[0063] Figure 8 An example of a daisy chain architecture is shown in which a fault management power system may be employed according to an embodiment of the present disclosure.

[0064] Fig. 9 An example of a fishbone architecture according to an embodiment of the present disclosure is shown in which a fault management power system may be employed.

[0065] Fig.10 The embodiment according to the present disclosure is shown Fig. 9 An enlarged partial view of a fishbone architecture having a junction box, a load, and related load-side components in which a fault management power system may be employed.

[0066] Fig.11 A fault managed power system of a single-pole power configuration with a grounded source, a 2-wire cable (shielded), and a single switch is shown in accordance with an embodiment of the present disclosure.

[0067] Fig.12 A fault managed power system of a single-pole power configuration with an isolated source, a 2-wire cable (shielded), and a single switch is shown in accordance with an embodiment of the present disclosure.

[0068] Fig.13 A fault managed power system of a single-pole power configuration with an isolated source (no shield), a 2-wire cable, and a single switch is shown in accordance with an embodiment of the present disclosure.

[0069] Fig.14 A fault managed power system of a single pole power configuration with a grounded source, 2-wire cable (shielded), and dual switches is shown in accordance with an embodiment of the present disclosure.

[0070] Fig.15A fault managed power system of a single pole power configuration with an isolated source, 2-wire cable (shielded), and dual switches is shown in accordance with an embodiment of the present disclosure.

[0071] Fig.16 A fault managed power system of a single pole power configuration with an isolated source (unshielded), a 2-wire cable, and dual switches is shown in accordance with an embodiment of the present disclosure.

[0072] Fig.17 A fault management power system of a bi-pole power configuration with a grounded source, 3-wire cable (shielded), and dual switches is shown in accordance with an embodiment of the present disclosure.

[0073] Fig.18 A fault managed power system of a bi-pole power configuration with isolated sources, 3-wire cable (shielded), and dual switches is shown in accordance with an embodiment of the present disclosure.

[0074] Fig.19 A fault managed power system with a bi-pole power configuration having an isolated source (unshielded), a 3-wire cable, and dual switches according to an embodiment of the present disclosure is shown.

[0075] Fig. 20 An example of sample data of a calibration table, such as a voltage reference (Vref) table, according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0076] According to one embodiment, a fault management power system and a method for implementing such a power system are provided for managing power on a power cable including at least one electrical conductor (or line). The fault management power system may include an upstream component (also referred to as a "source"), a downstream component (also referred to as a "load-side component" or "Fx"), and a power cable for transmitting a DC current / voltage (e.g., a DC steady-state current) from the source to the downstream component. The power system may use filters located upstream and downstream of the power cable to isolate the power cable from the upstream source and the downstream load, thereby providing a noise-free DC current / voltage on the cable. Human body contact with the cable may cause electrical interference to the cable. Before the load is powered on (e.g., before the DC current / voltage is supplied during the startup phase) and during the steady-state operation / phase when the DC current / voltage is also supplied, a pulse generator or generating circuit combined with a sensor system including an impedance sensor may be used to measure the electrical activity on the cable. Based on the measurements made by the sensor system, the occurrence of a fault may be detected, including but not limited to a fault caused by human body contact with the cable. In various embodiments, the sensor system may include an impedance sensor, a frequency selective filter such as a pi filter, and an amplifier circuit, and may measure electrical interference on the cable to facilitate detection of human contact or other faults on the cable. The capacitor in the impedance sensor and the inductor in the pi filter may form a tank circuit to amplify the fault signal on the power cable. The power system may also employ an electronic switch to interrupt (or prevent) the supply of electrical energy to the power cable in response to detection of a fault. The use of an electronic switch may enable rapid shutoff of the power supply to the cable, thereby reducing the shock protection to below the release limit established by UL.

[0077] The fault management power methods and systems of the present disclosure can provide various benefits / advantages. For example, the methods and systems can be configured to sense differential (line-to-line) leakage current in addition to ground fault (line-to-ground) leakage current to enhance shock and fire safety. The fault management power methods and systems can also employ DC current / voltage, such as DC steady-state current, between the source and downstream components, which can improve efficiency and eliminate EMI / RFI switching noise, thereby allowing power line communications for data transmission and load control. The fault management power methods and systems can also provide Class 4 power (or wiring), which can carry higher power levels (e.g., up to 450 volts) than, for example, Class 2 power, while providing enhanced shock and fire safety.

[0078] In various embodiments, fault detection may be performed during a startup phase before a DC current / voltage is provided to the power cable and / or during a steady-state operation phase when a DC current / voltage is provided to the power cable.

[0079] In various embodiments, the upstream and downstream filters may be low pass filters. The low pass filters may be π filters or other low pass filters.

[0080] In various embodiments, an electrical pulse, such as a voltage pulse, may be generated, whose pulse frequency is within a frequency range filtered out by the filter. For example, the frequency may be a high frequency, and the amplitude of the voltage may be sufficiently small (e.g., within a touch-safe range). The upstream sensor may be configured to measure a frequency signal within the pulse frequency range to facilitate detection of any electrical interference on the power cable.

[0081] In various embodiments, the fault management power method and system may also employ impedance sensors to detect faults caused by human contact with the cable and other types of faults on the cable. Detectable faults may include, but are not limited to, line-to-line faults and line-to-ground faults.

[0082] In various embodiments, the fault management power method and system may be used in different power distribution architectures, such as point-to-point architecture, radial architecture, daisy chain architecture, fishbone architecture (junction boxes may be used).

[0083] In various embodiments, the fault management power method and system can use various power cable configurations, such as 2-wire (twisted), 3-wire (twisted), etc. The power cable can also be unshielded or shielded. The power cable can also supply unipolar or bipolar power (e.g., voltage, current, etc.).

[0084] In various embodiments, the fault management power method and system can use one or more switches to interrupt (or prevent) the supply of power to the power cable. One or more switches may include, for example, an electromechanical switch, an electronic switch, a crowbar circuit, or other switching circuits and / or mechanisms. One or more switches may also be a single switch, a double switch, etc., depending on the power cable configuration, such as the number of conductors. For example, a double switch can be used with a power cable having 2 wires, 3 wires, or n wires (where n is a positive integer greater than 1).

[0085] In various embodiments, in the fault management power method and system, the power source may be a unipolar or bipolar power source (eg, a power supply (or source), a power converter, or other power component that can provide a negative or positive output voltage).

[0086] In other embodiments, the fault management power method and system may also provide a calibration process to perform fault detection in the electrical system, such as when different input / system voltages (V S ). The calibration process may involve adjusting the reference voltage (e.g., V Ref_Table reference voltage) to produce a calibration table and scale the reference voltage for use in performing fault detection. The calibration process can be used to detect physical contact of cables or other types of faults on an electrical (or power) system, or other types of conditions on an electrical system.

[0087] These and other example detection methods and systems of the present disclosure, and features related thereto, are shown and described in the accompanying drawings.

[0088] Figure 1A 1 shows an example of a block diagram of a fault management power system 100 using power cable isolation technology according to an embodiment of the present disclosure. The power system 100 includes a power source 110, a switch S1, an upstream filter 120 such as a low-pass filter, resistors R1 and R2, a switch S2, a capacitor C1, a diode D1, a switch S3, a sensor 140, an isolation switch S4, a current sensing device (e.g., I sense ), a current sensor of the power source 110, a power cable 150, a blocking diode D2, a downstream filter 160 such as a low pass filter, a power converter 170 such as a DC / DC or DC / AC converter, and a load 180. The power system 100 may also include one or more controllers 190 for controlling the various components of the system 100 and controlling, implementing or causing the various operations and functions described herein. The upstream components between the power source 110 and the cable 150 may generally be referred to as a "source" (or "source circuit"). The components downstream of the cable 150 or between the cable 150 and the load 180 may generally be referred to as "downstream components" or "load-side components" or "Fx".

[0089] The power source (or power source) or input power 110 can be an AC or DC power source. When an AC power source is used, the power system 100 can also include a power converter such as an AC / DC converter to provide DC power through the cable 150. In various embodiments, when a DC power source is used, the power system 100 can also include a power converter, such as a DC / DC converter. The power source / input power 110 can provide a system voltage V S .

[0090] The switch S1 is a switch operable to connect the power supply 110 to components downstream of the source, including the cable 150, or to disconnect the power supply 110 from these components. The switch S1 may be a mechanical switch or other switch that can be operated to an open position to disconnect the power supply 110 from these components, and to a closed position to connect the power supply to these components. The switch S1 may be operated manually or automatically. In other embodiments, the switch S1 may be alternatively located on the line side (upstream side) of the AC / DC power supply.

[0091] The upstream filter 120 and the downstream filter 160 may be low-pass filters, such as pi filters (also known as π filters) that may use LC components (or circuits). The filters 120, 160 may be configured to isolate the cable 150 from source-side / upstream noise and load-side / downstream noise to achieve noise-free transmission of DC current / voltage on the cable 150. In this example, the upstream filter 120 may also include a freewheeling diode D3 and a Zener diode D z , the downstream filter 160 may include a freewheeling diode D4.

[0092] Resistors R1 and R2 can be configured to provide a voltage V in , the voltage V in can be a scaled system voltage corresponding to the applied (operating) system voltage of the source circuit. In this example, the voltage V in Can be equal to Vs(R2 / (R1+R2)), or voltage V S Can be equal to V in ((R1+R2) / R2).

[0093] Switch S2 may be an electronic switch operable to quickly disconnect the power supply provided by power source 110 from cable 150 and connect the power supply provided by power source 110 to cable 150. In this example, switch S2 may be a solid-state switch.

[0094] In various embodiments, the pulse generator (or generating circuit) can be provided or implemented on or by the source through the operation of switch S2, which can be controlled to generate electrical pulses, such as by turning on switch S2 for a short time, such as (about 500us) and then turning off the switch. The pulse generator can be configured to generate electrical pulses, such as a voltage V that can be provided to the cable 150. p (or current). In various embodiments, electrical pulses, such as voltage pulses, may be generated to have a pulse frequency within the frequency range filtered out by the filters 120, 160. For example, the frequency may be a high frequency, and the amplitude of the voltage may be small enough (e.g., within a touch-safe range). In addition, in some embodiments, the switch S2 may be controlled to generate electrical pulses, such as by turning on the switch S2 for a short time, such as (approximately 500us), and then turning off the switch. According to one embodiment, although a pulse generator or its circuit may be implemented by the operation of the switch S2, it should be understood that other pulse generating circuits may be incorporated into the source to generate electrical pulses as desired.

[0095] The switch S3 may be an electronic switch that may be operated to short-circuit the source or source-side components to quickly interrupt and prevent power from the power source 110 to the cable 150. In this example, the switch S3 may be a crowbar circuit that quickly shorts the power supply line, or in other words blocks, for example, if the voltage and / or current exceeds a predetermined threshold.

[0096] The sensor 140 can sense or measure the electrical energy on the cable 150. The sensor 140 can include an impedance sensor and a frequency selective filter, such as a pi filter. In various embodiments, the impedance sensor combined with the pi filter can provide an energy tank circuit (also referred to herein as an "impedance sensor energy tank circuit") that can output an amplified voltage measurement value (V m or V out ), which voltage measurement value may correspond to an impedance difference on the cable 150 or a leakage current on the cable 150. The sensor measurement may be used to detect the occurrence or presence of a fault or a fault signal associated therewith (e.g., human contact or other fault on the cable 150). In this example, the impedance sensor may include a resistor Rd and an RC circuit (or component), and the filter may be a pi filter including an LC circuit (or component). In this example, the capacitor in the impedance sensor of the sensor 140 and the inductor in the pi filter may form a resonant circuit for tuning to a desired frequency or range in order to measure and detect electrical interference, such as electrical interference caused by a fault signal on the cable 150. In an embodiment, the impedance sensor may work in conjunction with a pi filter component, such as primarily an inductor and a capacitor closest to the impedance sensor, to provide an energy storage circuit.

[0097] In various embodiments, the tank circuit may be configured to measure a frequency signal within a pulse frequency range of the generated electrical pulses to facilitate detecting electrical disturbances on the power cable.

[0098] The switch S4 can be an isolation switch that can be operated to connect the source to a component (also referred to as a circuit) downstream of the source or to disconnect the source from the component. In various embodiments, the switch S4 can be operated to isolate the source circuit from downstream components, such as the power cable 150, the load, and load-side components, such as downstream filters, etc. For example, when performing an open circuit test (e.g., testing in an open circuit state) when measuring a reference voltage for calibration purposes, the source circuit can be isolated, as described herein.

[0099] Current sensors can be used to sense the current on a cable (e.g. I sense ). Current sensors can be used to detect leakage current or other current signals on cables, including fault signals.

[0100] The power cable 150 may be an electrical cable that may include one or more conductors (eg, conductors, wires, conductive wires, etc.). In various embodiments, the cable may be a 2-wire (twisted) cable, a 3-wire (twisted) cable, etc. The cable may also be shielded or unshielded.

[0101] The converter 170 may be a power converter, such as a DC / DC converter or a DC / AC converter. The type of converter depends on various factors, including application, load, etc.

[0102] The controller 190 may be configured to implement various functions and operations as described herein, including, but not limited to, controlling the operation of one or more components of the power system 100, performing or implementing fault detection, and managing the supply of power / energy from a source to or through the cable 150. The controller 190 may include an internal memory or be communicatively coupled to an external memory. The memory may store executable instructions or programs for controlling the operation of the controller (including the functions and operations described herein), data for implementing the fault management power method and system, etc., including system variables (e.g., counters, operating parameters, reference tables such as voltage reference tables, etc.), and any other data described herein.

[0103] For example, in one embodiment, the controller 190 can be configured to detect electrical interference on the power cable 150 based on measurements from the sensor 140 when electrical pulses or DC current / voltage and electrical pulses are provided to the power cable 150, the electrical interference corresponding to the occurrence of a fault caused by human body contact with the cable 150 (or its conductors) or other faults on the cable 150, and in response to detecting the occurrence of the fault, interrupt the supply of electrical energy to the power cable 150 via at least one upstream switch (e.g., switches S1, S2, S3 and / or S4), including electrical pulses or DC current / voltage and electrical pulses.

[0104] The above-described fault management power system of FIG1 is provided as an example only. The fault management power system may be modified, for example, by adopting one or more switches, upstream and / or downstream power converters, one or more sensors (e.g., impedance sensors, leakage sensors, or other sensors to detect faults caused by human contact with cables or other types of faults on the power system), different types of cables and architectures, etc. The fault management power system may also include a communication device that may be incorporated upstream and downstream of the power cable to implement power line communication (PLC) between the fault management power system or a distribution system including the fault management power system.

[0105] Figure 1BA simplified circuit schematic diagram is shown according to an embodiment of the present disclosure, showing an example of a circuit for measuring a fault on a cable. The simplified circuit can show the main components that can affect the transient response waveform detected by the sensor (e.g., 140). Example operation of the simplified circuit during steady state and startup will be described below.

[0106] For example, when switch S2 is closed and the system is in steady state, a fault may occur on the cable by closing switch S5 across the equivalent human body resistance R1. Closing switch S5 generates a transient in the entire system. The transient waveform shape (e.g., frequency and amplitude) can be determined primarily by components L1, C1, and R1. The value of C1 can be the peak voltage V measured by the controlled impedance sensor. m The impedance sensor can be used as a voltage divider to measure the transient voltage generated by the fault.

[0107] During the startup phase, before the full system voltage is applied, the voltage across C2 can be measured to determine if there is a fault on the cable. Switch S2 can be closed momentarily (e.g., 300 to 500 microseconds) to charge C1 and any other capacitance in the system (e.g., load, cable, etc.). The decay rate of C1 (e.g., voltage across C1) can be measured. If this decay rate exceeds a threshold, S2 remains open for a predetermined time. After this period of time, the process can be repeated. If the decay rate still exceeds the limit after the third attempt, the system can be locked, indicating a permanent fault. If the decay rate is within the limit, switch S2 can be closed and current will flow to the load. Diode D1 may be optional, but is preferred. One of its purposes is to prevent any stored energy on the load side from slowing down the discharge rate of the impedance sensor capacitor C2. Slower discharge of C2 will result in longer detection time, which may not meet the desired response time requirements, but may be acceptable for some applications. Cable impedance will also affect the measurement of the waveform, but not as much as Figure 1C For example, Figure 1C Waveforms from a SPICE model are shown, showing variations of the waveform and simplification of the circuit to identify and illustrate the main components used to detect faults on the cable. The first or second peak is important because it can be used to identify faults on the cable.

[0108] Figure 1D The switches (e.g., S1, S2, S3, and S4) according to an embodiment of the present disclosure are shown in an open position. Figure 1A 1 is a block diagram of a fault management power system 100. As shown in this example, the source at P1, P2 is disconnected or unconnected from downstream components (eg, cables, load-side components, etc.) by opening switch S4.

[0109] Figure 2 An example process 200 of operating a fault-managed power system or component thereof, which may employ power cable isolation techniques, according to an embodiment of the present disclosure is shown. As an example illustration, the process 200 will be described with reference to the exemplary fault-managed power system 100 (or component thereof) of FIG. 1. The various operations of the process 200 may be performed by or under the control of one or more controllers.

[0110] Process 200 begins at block 202 where a manual startup of a fault managed power system (eg, 100) is initiated.

[0111] At block 202, a fault management power system may be turned on to enable or initiate power supply operation to supply power from a power source to a power cable and its line conductors. For example, switch S1 may be closed. The power source may be a DC regulated power source. In various embodiments, an upstream power converter (e.g., an AC / DC converter, a DC / DC converter) may also be used to provide a desired DC power (e.g., a DC current or voltage ("DC current / voltage")) to a downstream component.

[0112] At block 204, the fault management power system may be initialized and system variables may also be initialized. For example, switches S2 and S3 may be opened and a variable count may be set to zero (eg, a counter may be set to zero or a default value).

[0113] At block 206, during the startup phase, an electrical pulse (or pulse signal) may be applied to the power cable by momentarily closing switch S2. p A voltage pulse of an amplitude of 1000 Å may be applied to the power cable. In various embodiments, the pulse output has a rise time within a frequency range that is filtered out (eg, blocked) by upstream and downstream filters.

[0114] At block 208, an electrical characteristic of the power cable is measured. For example, voltage (e.g., V m or V out ) is measured by a sensor such as 140. The measured voltage may correspond to an impedance change or difference on the power cable or a leakage current on the cable, which may reflect an electrical disturbance on the power cable.

[0115] At block 210, it is determined whether the measured electrical characteristic satisfies a preset threshold (or condition). For example, it may be determined whether the voltage V measured by a sensor such as an impedance sensor m or V outIf the measured voltage drops below the preset threshold, process 200 proceeds to block 220, which will be discussed further below. Otherwise, if the measured electrical characteristic does not meet the preset threshold, at block 212, a system voltage (e.g., a DC voltage) is applied, such as by closing switch S2, to initiate steady-state operation of the power system. For example, the applied system voltage from the source has been filtered, such as by an upstream filter, such as a low-pass filter, to isolate the cable from any noise or signal (e.g., a high-frequency signal) originating upstream of the cable.

[0116] At block 214, electrical characteristics of the power cable are measured. For example, voltage (V m or V out ) is measured by a sensor, such as an impedance sensor affected by a pi filter or the nearest LC component of an impedance sensor tank circuit. The measured voltage may correspond to an impedance change or difference on the power cable, or a leakage or other current on the cable.

[0117] At block 216, a determination is made as to whether a voltage pulse (e.g., between V m or V out If not, process 200 returns to block 214. Otherwise, if a voltage pulse is detected, at block 220, a fault on the cable (or a sign thereof) is detected, for example, contact with the cable (eg, human contact) or other fault on the cable is detected.

[0118] At box 222 , switch S2 is opened to disconnect the system voltage, and switch S3 is closed at box 224 to create a short circuit that releases any stored energy that may flow into the fault and clamps the voltage across the power cable to a safe level within a specified time.

[0119] At block 226, a counter is incremented. In this example, the counter is incremented by 1 (eg, Count=Count+1).

[0120] In box 230, determine whether the counter has reached a count threshold, which can be a preset (or predefined) count. In this example, the count threshold is 3. The count threshold can be configured or set to a number that can solve problems such as false alarms or false trips, or depend on other factors. If the count does not reach the count threshold (e.g., Count=3), process 200 proceeds to box 232, where a preset delay (e.g., a delay of 3 seconds (automatic restart)) is applied before restarting. In box 234, switch S3 is disconnected to interrupt the short circuit and allow power to be supplied to the cable. Process 200 then returns to box 206 to continue detecting the occurrence of body contact (e.g., contact between a human body and a conductor or wire of a cable, etc.) or other faults associated with the cable.

[0121] Returning to block 230, if the count threshold is reached (or satisfied), the system is tripped at block 240. For example, the tripping operation may be performed by opening switch S1 to stop or disconnect the power supply from the power source to the cable, and the power supply operation of the power system is stopped or terminated. Thereafter, process 200 may return to 202 to implement a manual start of the power system.

[0122] The above process 200 is provided as an example. The process 200 may be suitable for implementation on different power system architectures, including those described herein, which may include one or more line conductors or one or more switches, etc., for enabling or interrupting power supply on the line conductors of the power cable.

[0123] Figure 3A An example process 300 of operating a fault management power system or a component thereof according to an embodiment of the present disclosure is shown, which process may employ power cable isolation techniques and calibration processes. As an example illustration, the process 300 will be described with reference to the exemplary fault management power system 100 (or a component thereof) of FIG. 1. The various operations of the process 300 may be performed by or under the control of one or more controllers.

[0124] Process 300 begins at block 302 where a manual startup of a fault-managed power system (eg, 100 ) is initiated.

[0125] At block 304, the fault management power system may be turned on to enable or initiate power supply operation to supply power from the power source to the power cable and its line conductors. For example, switch S1 may be closed. The power source may be a DC regulated power source. In various embodiments, an upstream power converter (e.g., an AC / DC converter, a DC / DC converter) may also be used to provide a desired DC power (e.g., a DC current or voltage ("DC current / voltage")) to a downstream component.

[0126] At block 306 , the fault management power system may be initialized and system variables may also be initialized. For example, switches S1 and S4 are closed, switch S3 is open, and a variable COUNT may be set to zero (eg, a counter is set to zero or a default value).

[0127] The fault management power system can also access or read voltage calibration measurement reference tables (such as V ref Vref_Table can be obtained by turning on S2 for a period of time (e.g. 1 second) and then immediately starting to measure the voltage at both ends of the power cable (e.g. Figure 1A The voltage at points P1 and P2 in the table is generated by the voltage at the two ends of the table. This voltage may be referred to as the Vref_Table reference voltage.

[0128] Vref_Table={V_Ref1,V_Ref2,V_Ref3,V_Ref4,V_Ref5,……,V_Refn},

[0129] Where n is the calibration table V Ref An example of a calibration procedure for generating a reference table of voltage calibration measurements is given below. Figure 3B As further described in the examples of , positive and negative reference voltages can be generated.

[0130] During this voltage calibration measurement, the downstream components / circuits (such as loads and cables) are disconnected from the source. This is an open circuit test of the source circuit. These measurements are stored as constants in the software, such as in a calibration table, and are referred to as V Ref In normal operation, the switch S2 is first closed for a period of time (e.g., 500us), which causes the capacitor C (V C ) generates a voltage pulse. The voltage across capacitor C is measured with a time delay of Tdelta, and then the voltage V C Delta and Slope are calculated for each value of , which will be described in further detail below. Fig. 20 The calibration table V is provided in Ref Example of sample data for _Table.

[0131] At block 308, the fault management power system may measure various electrical characteristics in the system, such as various current and voltage measurements. In this example, the measurements may include the voltage V in , where V in is the input voltage (eg, the input system voltage). In various embodiments, V in level, and if it is within desired predetermined limits, process 300 may proceed (otherwise process 300 may remain on hold).

[0132] At block 310, during the startup phase, an electrical pulse (or pulse signal) may be applied to the power cable by momentarily closing switch S2. p A voltage pulse of an amplitude of 1000 Å may be applied to the power cable. In various embodiments, the pulse output has a rise time within a frequency range that is filtered out (eg, blocked) by upstream and downstream filters.

[0133] At block 312, the fault management power system may measure various electrical characteristics, such as various current and voltage measurements. In this example, the measurements may include a voltage V C and V out and current I1, where V C is the voltage across the sensor’s capacitor, V outis the voltage measured by the sensor or the sensor's tank circuit, and I1 is the current measured through the cable (e.g., I sense ).

[0134] For example, a voltage (such as V out or V m ) may be measured by a sensor such as 140. The measured voltage may correspond to an impedance change or difference on the power cable or a leakage current on the cable, which may reflect electrical disturbances on the power cable.

[0135] At block 314, the fault management power system calculates various ratios for scaling calibration measurements, such as V Ref _Table. Since different system input voltages (Vs) may be allowed but subject to upper and lower limits, it may be necessary to adjust V Ref _Table voltage is scaled so that all table reference values ​​are scaled for a system voltage that is different from the voltage used for calibration. Voltage Vrated is the system voltage at which the values ​​from the calibration table Vrated are recorded. Ref _Table of voltage references.

[0136] For example, the fault management power system calculates the applied system voltage (V s ) and the voltage during system calibration (V rated ) to obtain the value V ref , for example using the following example equation:

[0137] Ratio=V s / V rated ;and

[0138] V Ref =Ratio*V Ref _Table,

[0139] in:

[0140] Vs is the applied open circuit system voltage,

[0141] Vin = Vs (R2 / (R1+R2) is the scaled system voltage Vs, and

[0142] V rated is the system voltage, at this voltage record the calibration table V Ref _Table of reference voltages.

[0143] Typically, the voltage Vin can be the system voltage V S , which is scaled by the resistor divider ratio (eg, R2 / (R1+R2) in the example of FIG. 1 ).

[0144] At block 316, the fault management power system measures the voltage V C The voltage Vm measured during the pulse application during startup can be used to determine whether the cable and downstream hardware are connected.

[0145] At block 318 , the fault management power system calculates a scaled reference voltage V Ref and the voltage across the capacitor V C The difference between the two is called Delta. The fault management power system also calculates the change in voltage across the capacitor over time (or a period of time), which is called Slope. Example equations for Delta and Slope are as follows:

[0146] Ratio=V s / V rated ;

[0147] V ref[i] =Ratio*V ref _Table[i];

[0148] Delta=V ref [i]-V C [i]; and

[0149] Slope=(V C [i-1]–V C [i]) / dt,

[0150] in:

[0151] V rated is to create a voltage reference table for calibration (e.g. Fig. 20 ) when the system voltage is

[0152] V in It is the scaled steady-state system input voltage Vs under open circuit condition (ie S2 is open).

[0153] V ref _Table[i] is a calibration table of multiple measured values ​​of reference voltage (V_Ref1, V_Ref2, V_Ref3, V_Ref4, V_Ref5, …, V_Refn),

[0154] V Ref[i] is from the calibration table V ref _Table's scaled reference voltage for the i-th reference voltage,

[0155] dt is T delta , which is the step time or time interval,

[0156] V C is the voltage measured across the capacitor of the impedance sensor,

[0157] Delta is the difference, and

[0158] Slope is the change in voltage over time, and

[0159] i = 1 to n (where n can be the calibration table V Ref _Table).

[0160] At block 320, the fault management power system determines the presence (or absence) of an electrical disturbance on the power cable corresponding to the occurrence of a fault caused by a body contacting the cable (e.g., a body contacting a conductor or wire of the cable) or other fault on the cable. For example, the fault management power system may compare the Slope and Delta to reference values ​​(e.g., thresholds or values ​​thereof). If the Slope and Delta exceed the respective reference values, a fault is detected. The thresholds may be scaled thresholds, which may be relative to the current system voltage (V in ) and calibrate the system voltage (V rated ) ratio.

[0161] If the Slope and Delta exceed the reference values, the process 300 proceeds to block 330, which will be discussed further below. Otherwise, if the Slope and Delta do not exceed the reference values, then at block 322, a system voltage (e.g., a DC voltage) is applied, such as by closing switch S2, to initiate steady-state operation of the power system. For example, the applied system voltage from the power source has been filtered, such as by an upstream filter, such as a low-pass filter, to isolate the cable from any noise or signal (e.g., a high-frequency signal) originating upstream of the cable.

[0162] At block 324, electrical characteristics of the source and the power cable are measured, such as a voltage V measured by a voltage sensor. in and voltage V out and the current I1 (or I sense ).

[0163] At block 326, it is determined whether V m ,V outIf a voltage pulse is not detected, process 300 returns to block 324 to further measure and evaluate electrical characteristics. Otherwise, if a voltage pulse is detected at block 326, physical contact (e.g., human body contact) of the cable (or its conductors) or other fault on the cable is detected at block 330.

[0164] At block 332, switch S2 is opened to disconnect the system voltage. At block 334, switch S3 is closed to create a short circuit that releases any stored energy that may flow into the fault and clamps the voltage across the power cable to a safe level for a specified time.

[0165] At block 336, the counter is incremented. In this example, the counter is incremented by 1 (eg, Count=Count+1).

[0166] At block 338 , a delay is provided, such as 3 seconds or thereabouts (eg, a preset delay before automatic restart).

[0167] At box 340, it is determined whether the counter has reached a count threshold, which may be preset (or predefined). In this example, the count threshold is 3. The count threshold may be configured or set to a number, which may address issues such as false alarms or false trips, or may depend on other factors. If the count does not reach the count threshold (e.g., Count=3), the process 300 proceeds to box 342, where the switch S3 is opened to interrupt the short circuit and allow power to be supplied to the cable. The process 300 then returns to box 206 to continue detecting any occurrence of body contact (e.g., contact between a human body and a conductor or wire of a cable, etc.) or other faults associated with the cable.

[0168] Returning to block 340, if the count threshold is reached, the system is tripped. For example, the tripping operation is performed by opening switch S1 to stop or disconnect the power supply from the power source to the cable, and the power supply operation of the power system is stopped or terminated. Thereafter, process 300 may return to 302 to implement manual startup of the power system.

[0169] The above process 300 is provided as an example. The process 300 may be suitable for implementation on different power system architectures, including those described herein, which may include one or more line conductors or one or more switches, etc., for enabling or interrupting power supply on the line conductors of the power cable.

[0170] Figure 3B The generation voltage reference table (eg, V ref _Table) of the example calibration process 350. For the purpose of explanation, reference will be made to Figure 1DThe process 350 is described with reference to a source (or source module / circuit) of FIG. 350. In this example process 350, no load is connected to the source module at P1, P2; a precise nominal voltage can be applied at the input; and separate reference voltage tables (e.g., Vref_Table) can be created for the +Ve (positive voltage) and –Ve (negative voltage) supplies. Fig. 20 An example of such a separate table (and sample data thereof) is shown in The various operations of process 350 may be performed by or under the control of one or more controllers.

[0171] Process 350 begins at block 352 where a nominal voltage is applied at the input and switch S1 is turned to a closed position to connect the source to the input power.

[0172] At block 354, switches S3 and S4 are placed in the open position.

[0173] At block 356, switch S2 is closed for a period of time, such as T duration T. T duration is the time the voltage stabilizes (eg, one (1) second).

[0174] At block 358, the voltage V is measured at a time step of Tdelta. C , for example using a voltage or other suitable sensor.

[0175] At block 360, a voltage reference table (eg, V ref _Table).

[0176] At block 362, a determination is made as to whether sampling is complete. For example, the number of samples (eg, Count) may be compared to a threshold (or limit) to determine whether a sufficient number of samples have been collected.

[0177] If sampling is complete (e.g., the number of samples equals or reaches a threshold (or limit)), process 350 terminates. Otherwise, process 350 proceeds to block 364, where data (e.g., reference voltage measurements or a table thereof) is saved to a file. At block 366, a counter is incremented, e.g., Count=Count+1. At the beginning of process 350 or when no samples are collected and saved, the value of Count may be set or initialized to zero. Thereafter, process 350 returns to block 358 to continue sampling voltage V C Perform sampling measurements until sampling is determined to be complete.

[0178] exist Fig. 20 An example of a voltage reference (Vref) table (also referred to as a calibration table) is shown in FIG, which will be described in further detail below. The calibration table may include a table or array of positive reference voltages and a table or array of negative reference voltages.

[0179] Figure 4AAn example process 400 for operating a fault management power system or component thereof according to an embodiment of the present disclosure is shown, which process may employ power cable isolation techniques. As an example illustration, the process 400 will be described with reference to the exemplary fault management power system 100 (or component thereof) of FIG. 1 , such as a source / source circuit, a downstream component (or circuit), and a power cable for delivering electrical energy from the source to the downstream component (or circuit). The power cable may include at least one conductive wire. The various operations of the process 400 may be performed by or under the control of one or more controllers.

[0180] Process 400 begins at block 402, where a power cable is isolated from upstream noise or signals using an upstream low pass filter of a source. For example, the upstream low pass filter may be connected between the power source and the power cable.

[0181] At block 404 , the power cable is isolated from downstream noise or signals using a downstream low pass filter of a downstream component.

[0182] At block 406, electrical energy is supplied from a source to the power cable, including electrical pulses or DC current / voltage and electrical pulses. For example, the electrical pulses may be generated by operating a switch (as described herein) or other pulse generating circuits of the source. Electrical energy may be selectively provided to the power cable by the source. For example, the source may selectively provide electrical pulses and / or DC current / voltage and electrical pulses to the power cable. In various embodiments, the source may supply electrical pulses during the startup phase and then, during steady-state operation of the power system, allow the supply of DC current / voltage or the supply of DC current / voltage together with electrical pulses.

[0183] At block 408, the electrical activity associated with the electrical pulses on the power cable is measured using an impedance sensor of the source. The impedance sensor may be disposed between the pulse generator / pulse generating circuit (or component) and the power cable. In various embodiments, additional sensors such as leakage sensors may be employed to measure the electrical activity on the power cable.

[0184] In box 410, when an electrical pulse or a DC current / voltage is provided to the power cable together with the electrical pulse, the occurrence of electrical interference on the cable is detected (e.g., detected, determined, identified, etc.) based on measurements from a sensor or an impedance sensor energy storage circuit of the sensor, which corresponds to the occurrence of a fault caused by body contact with the power cable (or its conductors).

[0185] At block 412 , in response to detecting the occurrence of a fault, supply of electrical energy from the source to the power cable is interrupted (or blocked) via at least one upstream switch.

[0186] The above process 400 is provided as an example. The process 400 may be suitable for implementation on different power system architectures, including those described herein, which may include one or more line conductors or one or more switches, etc., for enabling or interrupting power supply on the line conductors of the power cable.

[0187] Figure 4B An example calibration process 450 in a detection system for an electrical or power system according to an embodiment of the present disclosure is shown. As an example illustration, the process 450 will be described with reference to the exemplary fault management power system 100 (or components thereof) of FIG. 1, such as a source / source circuit, a downstream component / circuit, and a power cable for transmitting electrical energy from the source to the downstream component. The power cable may include at least one conductive wire. The various operations of the process 450 may be performed by or under the control of one or more controllers.

[0188] At block 452, when a first system voltage (eg, V rated When applied to a source circuit, the system uses a sensor to measure a reference voltage across the source circuit while it is in an open circuit state for a predetermined period of time. The reference voltage is the voltage to be provided from the source circuit to downstream components that may be connected thereto. The sensor makes multiple measurements of the reference voltage over time and stores them in memory. For example, the multiple measurements of the reference voltage may be stored in a calibration table (e.g., V Ref _Table).

[0189] In various embodiments, the sensor may be or include an impedance sensor having an RC component. The sensor may also include a filter having an LC component, which together with the RC component may provide a tank circuit. The sensor may provide a voltage measurement, such as a voltage measurement across a capacitor of the RC component of the sensor.

[0190] At block 454, when a second system voltage (eg, V s When applied to a source circuit, the system uses a sensor to measure the voltage across the source circuit when it is in an open circuit state (also called an "open circuit") for a predetermined period of time.

[0191] At block 456 , the system scales the reference voltage from the plurality of measurements of the reference voltage relative to the second system voltage according to a ratio between the second system voltage and the first system voltage to provide a scaled reference voltage.

[0192] At block 458 , the system calculates the difference (eg, Delta) between the scaled reference voltage and the voltage across the source circuit measured by the sensor at the second system voltage.

[0193] At block 460 , the system calculates a change in voltage over time (eg, Slope) between the previous voltage and the voltage measured by the sensor at the second system voltage over a predetermined period of time.

[0194] The system compares the difference and the change in voltage over time to corresponding thresholds at block 462. The thresholds may be scaled thresholds that may be scaled according to a ratio between the second system voltage and the first system voltage to provide a scaled reference voltage.

[0195] In various embodiments, the system can also detect the type of circuit configuration of the downstream circuit (connectable to the source circuit) and configure the threshold value according to the detected downstream circuit configuration. The type of circuit configuration can include a single load, multiple loads, or other circuit configurations described herein.

[0196] In response to the comparison, the system determines whether a condition on the electrical system has occurred at block 464. The condition may include, but is not limited to, physical contact of the power cable (e.g., human or other physical contact of a conductor of the power cable) or other faults on the power cable (e.g., arc faults, ground faults, etc.), including those described herein.

[0197] The calibration process 450 can be used with a fault management power system such as 100 described herein, or with other types of detection systems for detecting different kinds of conditions on an electrical (or power) system, including those described herein. In addition, the calibration process 450 can be used in conjunction with other detection processes, such as those described herein, to detect faults on a cable or other conditions on a cable or electrical / power system. The process 450 can also be adapted for implementation on different power system architectures, including those described herein, which can include one or more line conductors or one or more switches, etc., for enabling or interrupting power supply on a line conductor of a power cable.

[0198] Figure 5A An example of a graph 500 is shown showing a variation of a voltage sensed on a conductor (e.g., a power cable) over time in relation to a human body model (HBM) according to an embodiment of the present disclosure. In this example, the voltage Vc may be the voltage of a sensing capacitor (e.g., the capacitor of the impedance sensor 140 of FIG. 1 ) associated with a startup phase. Similarly, Figure 5B An example of a graph 550 showing a voltage sensed on a conductor (e.g., a power cable) over time in relation to a human body model (HBM) is shown in accordance with an embodiment of the present disclosure. In this example, the voltage Vout may be an output voltage from a sensor (e.g., the impedance sensor tank circuit of FIG. 1 ) in relation to a steady-state operating phase.

[0199] exist Figure 5AThe graph of 500 and Figure 5B In the graph 550, the sensing voltage curves of different human body models (e.g., different resistances) are shown, which can reflect different types of human contact with the cable, such as the part of the body in contact with the cable, the amount of body contact with the cable, line-to-line human contact, line-to-ground human contact, etc. HBM can be predetermined for different human contact scenarios, including no touch / contact scenarios. HBM can be used as a proxy for actual manual testing to test the detection of faults based on measurements of the electrical characteristics of the monitored cable, such as human contact with the cable. Other voltage models can also be used to detect other types of faults on the power cable based on sensor measurements.

[0200] For example, a DC fault management power system may employ filters on both the source and load (or Fx) sides, as described herein, which in turn may provide a "noise-free" DC voltage or current on the interconnecting cable. The introduction of a fault (such as human contact, etc.) may generate an interference pulse that can be measured by a sensor. The sensor may output a voltage or other electrical measurement value, which may correspond to an impedance change on the monitored cable or a leakage current on the monitored cable. For example, the peak value of the pulse may be proportional to the leakage current. The presence of a pulse at Vc or Vout may indicate human contact on one or more wires of a cable connecting the source side / upstream and load side / downstream filters. The filter may be a low-pass filter such as a π filter, or other low-pass filters for filtering out noise such as high-frequency noise or signals. In response to detecting the occurrence of such a fault, the fault management power system may use a switch or the like to interrupt or block the supply of power supply (e.g., voltage, current, etc.) through the cable. In various embodiments, rapid disconnection and blocking may allow the fault management power system to meet the earthquake / fire protection requirements and other safety requirements of a Class 4 power system.

[0201] Figures 6 to 10 Various power distribution architectures are shown that can employ the fault management power methods and systems described herein. Typically, these different architectures include one or more sources, one or more downstream components (load-side components or FX), and one or more power cables connected between the source and load-side components. As described herein, the source and downstream components may include upstream and downstream filters to isolate the cable from noise (e.g., filter out any noise within a desired frequency range from the upstream source and downstream load), and the source may include a pulse generating circuit and an impedance sensor to measure electrical activity on the power cable. The measurements from the sensor may be used, for example, by a controller to detect the occurrence of a fault, such as human contact with the cable or other faults. In response to detecting the occurrence of a fault, one or more switches are used to interrupt (or prevent) the power supplied to one or more power cables. These example architectures will be described in further detail below.

[0202] Figure 66 shows an example of a point-to-point architecture 600 in which a fault management power system (as described herein) may be employed according to an embodiment of the present disclosure. Figure 6 As shown, architecture 600 includes a source, downstream components, and a power cable connected between the source and the downstream components. The power cable can deliver power from a single source to a single set of downstream components or Fx. The power supplied can be a unipolar voltage (e.g., 450 volts) or a bipolar voltage (e.g., ±225 volts).

[0203] Figure 7 7 shows an example of a radial architecture 700 in which a fault management power system (as described herein) may be employed according to an embodiment of the present disclosure. Figure 7 As shown, the architecture 700 includes a single source that can provide power to multiple sets of downstream components or Fx (and their associated loads) through corresponding power cables. A fault management power subsystem can be implemented between the source and each set of downstream components or Fx. The power supplied can be a unipolar voltage (e.g., 450 volts) or a bipolar voltage (e.g., ±225 volts).

[0204] Figure 8 8 shows an example of a daisy chain architecture 800 in which a fault management power system (as described herein) may be employed according to an embodiment of the present disclosure. Figure 8 As shown, the architecture 800 includes a single source that can provide power to multiple sets of downstream components or Fx (and their associated loads). The multiple sets of downstream components or Fx are connected in series via power cables. The power supplied can be a unipolar voltage (e.g., 450 volts) or a bipolar voltage (e.g., ±225 volts).

[0205] Fig. 9 900 according to an embodiment of the present disclosure, in which a fault management power system (as described herein) may be employed. Fig. 9 As shown, the source is connected to one or more series of junction boxes, which in turn are connected to multiple groups of downstream components or Fx (e.g., a pair of grouped downstream components or Fx). The power supplied can be a unipolar voltage (e.g., 450 volts) or a bipolar voltage (e.g., ±225 volts). Power line communication can be performed to transmit data through the fishbone structure, for example by using frequencies that are not filtered out by upstream or downstream filters or frequency ranges for detecting faults. Fig.10 The architecture 1000 is shown in Fig. 9 A magnified partial view of the fishbone architecture.

[0206] Figures 11 to 19Various examples of cable configurations are shown that can be used for fault management power methods and systems (as described herein). In addition to upstream and downstream filters, switches, power cables, and power converters, the fault management power systems in these examples can also include additional upstream components that can be incorporated on the source side. These components can include pulse generating circuits and impedance sensors to measure electrical activity on the power cable. For example, measurements from the sensors can be used by a controller to detect the occurrence of a fault, such as a human body contacting the cable or other fault. In response to detecting the occurrence of a fault, one or more switches are used to interrupt (or prevent) the supply of electrical energy to one or more power cables. These exemplary fault management power systems will be described in further detail below.

[0207] Fig.11 FIG. 1 shows a fault management power system 1100 using a single-pole power configuration according to one embodiment. Fig.11 As shown, the power system 1100 may include: a source including an upstream grounded source, an upstream power converter (e.g., an AC / DC converter), an upstream filter, and a single switch; a power cable; and downstream components including a downstream filter and a downstream power converter (e.g., a DC / DC converter or a DC / AC converter) connected to a load. In this example, the power cable is a 2-wire (twisted) shielded cable. As shown, the power cable includes conductors (e.g., lines L1 and L2) and a shield s. The upstream switch is connected between the upstream filter and the conductor L1.

[0208] Fig.12 FIG. 1 shows a fault management power system 1200 using a single-pole power configuration according to one embodiment. Fig.12 As shown, the power system 1200 may include: a source including an upstream isolation source, an upstream power converter (e.g., an AC / DC converter), an upstream filter, and a single switch; a power cable; and downstream components including a downstream filter and a downstream power converter (e.g., a DC / DC converter or a DC / AC converter) connected to a load. In this example, the power cable is a 2-wire (twisted) shielded cable. As shown, the power cable includes conductors (e.g., lines L1 and L2) and a shield s. The upstream switch is connected between the upstream filter and the conductor L1.

[0209] Fig.13 FIG. 1 shows a fault management power system 1300 using a single-pole power configuration according to one embodiment. Fig.13As shown, the power system 1300 may include: a source including an upstream isolation source, an upstream power converter (e.g., an AC / DC converter), an upstream filter, and a single switch; a power cable; and downstream components including a downstream filter and a downstream power converter (e.g., a DC / DC converter or a DC / AC converter) connected to a load. In this example, the power cable is an unshielded 2-wire (twisted) cable. As shown, the power cable includes conductors, such as lines L1 and L2. The upstream switch is connected between the upstream filter and the conductor L1.

[0210] Fig.14 FIG. 1 shows a fault management power system 1400 using a single-pole power configuration according to one embodiment. Fig.14 As shown, the power system 1400 may include: a source including an upstream grounded source, an upstream power converter (e.g., an AC / DC converter), an upstream filter, and a dual switch; a power cable; and a downstream component including a downstream filter and a downstream power converter (e.g., a DC / DC converter or a DC / AC converter) connected to a load. In this example, the power cable is a 2-wire (twisted) shielded cable. As shown, the power cable includes conductors, such as lines L1 and L2, and a shield s. Upstream and downstream filters are provided for conductors L1 and L2. The upstream dual switch is connected between the upstream filter and their corresponding conductors (e.g., L1 and L2), and can be operated to connect the conductor to or disconnect from the power supply provided by the source or its components.

[0211] Fig.15 FIG. 1 shows a fault management power system 1500 using a single-pole power configuration according to one embodiment. Fig.15 As shown, the power system 1500 may include: a source including an upstream isolation source, an upstream power converter (e.g., an AC / DC converter), an upstream filter, and a dual switch; a power cable; and a downstream component including a downstream filter and a downstream power converter (e.g., a DC / DC converter or a DC / AC converter) connected to a load. In this example, the power cable is a 2-wire (twisted) shielded cable. As shown, the power cable includes conductors, such as lines L1 and L2, and a shield s. Upstream and downstream filters are provided for conductors L1 and L2. The upstream dual switch is connected between the upstream filter and their corresponding conductors (e.g., L1 and L2), and can be operated to connect the conductor to or disconnect from the power supply provided by the source or its components.

[0212] Fig.16 FIG. 1 shows a fault management power system 1600 using a single-pole power configuration according to one embodiment. Fig.16As shown, the power system 1600 may include: a source including an upstream isolation source, an upstream power converter (e.g., an AC / DC converter), an upstream filter, and a dual switch; a power cable; and a downstream component including a downstream filter and a downstream power converter (e.g., a DC / DC converter or a DC / AC converter) connected to a load. In this example, the power cable is an unshielded 2-wire (twisted) cable. As shown, the power cable includes conductors, such as lines L1 and L2. Upstream and downstream filters are provided for conductors L1 and L2. The upstream dual switch is connected between the upstream filter and their corresponding conductors (e.g., L1 and L2), and can be operated to connect the conductor to or disconnect from the power supply provided by the source or its components.

[0213] Fig.17 FIG. 1 shows a fault management power system 1700 using a bipolar power configuration according to one embodiment. Fig.17 As shown, the power system 1700 may include: a source including an upstream ground source, an upstream power converter (e.g., an AC / DC converter), an upstream filter, and a dual switch; a power cable; and a downstream component including a downstream filter and a downstream power converter (e.g., a DC / DC converter or a DC / AC converter) connected to a load. In this example, the power cable is a 2-wire (twisted) shielded cable, and the upstream power converter can be used for bipolar power. As shown, the power cable includes conductors (e.g., wires L1 and L2 and neutral N) and shielding s. Upstream and downstream filters are provided for wires L1 and L2. The upstream dual switch is connected between the upstream filter and their corresponding conductors (e.g., L1 and L2), and can be operated to connect the conductor to or disconnect from the power supply provided by the source or its components.

[0214] Fig.18 FIG. 1 shows a fault management power system 1800 using a bipolar power configuration according to one embodiment. Fig.18 As shown, power system 1800 may include: a source including an upstream isolation source, an upstream power converter (e.g., an AC / DC converter), an upstream filter, and a dual switch; a power cable; and a downstream component including a downstream filter and a downstream power converter (e.g., a DC / DC converter or a DC / AC converter) connected to a load. In this example, the power cable is a 2-wire (twisted) shielded cable, and the upstream power converter can be used for bipolar power. As shown, the power cable includes conductors, such as lines L1 and L2 and a neutral N and a shield s. Upstream and downstream filters are provided for conductors L1 and L2. The upstream dual switch is connected between the upstream filter and their corresponding conductors (e.g., L1 and L2), and can be operated to connect the conductor to or disconnect from the power supply provided by the source or its components.

[0215] Fig.19FIG. 1 shows a fault management power system 1900 using a bipolar power configuration according to one embodiment. Fig.19 As shown, power system 1900 may include: a source including an upstream isolation source, an upstream power converter (e.g., an AC / DC converter), an upstream filter, and a dual switch; a power cable; and a downstream component including a downstream filter and a downstream power converter (e.g., a DC / DC converter or a DC / AC converter) connected to a load. In this example, the power cable is an unshielded 2-wire (twisted) cable, and the upstream power converter can be used for bipolar power. As shown, the power cable includes conductors, such as lines L1 and L2 and a neutral N. Upstream and downstream filters are provided for conductors L1 and L2. The upstream dual switch is connected between the upstream filter and their corresponding conductors (e.g., L1 and L2), and can be operated to connect the conductor to or disconnect from the power supply provided by the source or its components.

[0216] Fig. 20 An example of sample data of a calibration table (e.g., a voltage reference (Vref) table) according to an embodiment of the present disclosure is shown. As shown, the calibration table may include a table or array of positive reference voltages and a table or array of negative reference voltages. These calibration measurements may be performed by a sensor, and the sensor measurements will be used to detect the condition of an electrical or power system. In various embodiments, the sensor may be or include an impedance sensor or an RC circuit, and the reference voltage may be a measurement across a capacitor of the sensor, which may be performed when the source / source circuit is in an open circuit state (e.g., an open circuit test). As described herein, the reference value may be scaled for the detection of an execution condition, such as contact of a power cable or other faults on an electrical or power system. It should also be understood that the example embodiments disclosed and taught herein are susceptible to many and various modifications and alternative forms. Therefore, the use of singular terms, such as but not limited to "one", etc., is not intended to limit the number of items. In addition, the naming conventions of various components, functions, features, thresholds, and other elements used herein are provided as examples and may be given different names or labels. The use of the term "or" is not limited to an exclusive "or" and may also mean "and / or".

[0217] It should be understood that the development of actual, real business applications incorporating aspects of the disclosed embodiments will require many implementation-specific decisions to achieve the developer's ultimate goals for the business embodiments. Such implementation-specific decisions may include, and may not be limited to, compliance with system-related, business-related, government-related, and other constraints, which may vary with the specific implementation, location, and time. While the developer's efforts may be complex and time-consuming in an absolute sense, such efforts are still routine tasks for those skilled in the art who benefit from this disclosure.

[0218] Using the description provided herein, the example embodiments may be implemented as a machine, process, or article of manufacture by using standard programming and / or engineering techniques to produce programming software, firmware, hardware, or any combination thereof.

[0219] Any resulting program with computer-readable program code may be contained on one or more tangible or non-transitory computer-usable media, such as a resident memory device, a smart card or other removable memory device or a transmission device, thereby forming a computer program product or article of manufacture according to an embodiment. Therefore, the terms "article of manufacture" and "computer program product" as used herein are intended to include a computer program that resides permanently or temporarily on any computer-usable or storage medium or in any transmission medium that transmits such a program.

[0220] The processor, controller or processing unit described herein may be a processing system, which may include one or more processors, such as a CPU, controller, ASIC or other processing unit or circuit, which controls or performs the operation of the device or system described herein. The memory / storage device may include, but is not limited to, a disk, a solid-state drive, an optical disk, a removable storage device such as a smart card, a SIM, a WIM, a semiconductor memory such as RAM, ROM, PROMS, etc. The transmission medium or network includes, but is not limited to, communication via wired communication, wireless communication (e.g., radio frequency (RF) communication, Wired communications may include transmission via Wi-Fi, Li-Fi, etc., the Internet, an intranet, telephone / modem-based network communications, hardwired / cabled communication networks, satellite communications, and other fixed or mobile network systems / communication links. Wired communications may include power line communications.

[0221] The flow charts and block diagrams in the accompanying drawings illustrate the possible architectures, functions and / or operations of various embodiments of the present disclosure. In this regard, each box in the flow chart or block diagram can represent a module, a code segment or a portion, which includes one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative embodiments, the functions marked in the box may not occur in the order marked in the figure. For example, two boxes displayed in succession can actually be executed substantially at the same time, or these boxes can sometimes be executed in the opposite order, depending on the functions involved. It will also be noted that each box illustrated in the block diagram and / or flow chart and the combination of boxes in the block diagram and / or flow chart can be implemented by a system based on special-purpose hardware or a combination of special-purpose hardware and computer instructions that performs a specified function or action.

[0222] While particular embodiments and applications of the present disclosure have been illustrated and described, it will be understood that the disclosure is not limited to the precise construction and configuration disclosed herein and that various modifications, changes and variations will be apparent from the foregoing description without departing from the invention defined in the appended claims.

Claims

1. A fault management power system, comprising: A power cable comprising at least one conductive wire for transmitting electrical energy; A source connected upstream of the power cable for supplying electrical energy to the power cable, including electrical pulses or DC current / voltage together with electrical pulses, the electrical pulses being generated by momentary operation of the source, the source comprising: An upstream low-pass filter, connected between the power source and the power cable, is used to isolate the power cable from upstream noise or signals. A sensor, including an impedance sensor tank circuit, for measuring electrical activity associated with electrical pulses on a power cable, and at least one upstream switch arranged upstream of the power cable, and At least one controller configured to: detecting an electrical disturbance on the power cable corresponding to the occurrence of a fault or other type of fault due to contact of a body with the cable based on measurements from the impedance sensor when an electrical pulse or a DC current / voltage together with the electrical pulse is supplied to the power cable, and In response to detecting the occurrence of a fault, interrupting the supply of electrical energy to the power cable via at least at least one upstream switch; and A downstream component, connected downstream of the power cable, for receiving electric energy supplied through the power cable, the downstream component comprises: Downstream low pass filter to isolate the power cable from downstream noise or signals.

2. The system according to claim 1, wherein: The impedance sensor energy storage circuit is configured to sense impedance changes on a power cable or leakage current on the cable. The sensor includes an impedance sensor with an RC component and a pi filter with an LC component. The capacitor in the impedance sensor and the inductor in the pi filter form an energy storage circuit to amplify the fault signal on the cable.

3. The system according to claim 1, wherein: The at least one upstream switch comprises a switch that is turned on and off to generate electrical pulses by momentary operation of the source.

4. The system according to claim 1, wherein: The source further comprises an upstream power converter, located upstream of the upstream low pass filter, for converting electrical energy supplied from the power source, and The downstream component further includes a downstream power converter, which is located downstream of the downstream low-pass filter and is used for converting the electric energy received from the power cable and providing the converted electric energy to the downstream load.

5. The system according to claim 1, wherein: The at least one switch comprises: a first upstream switch; a second upstream switch comprising a solid state switch; and a third upstream switch comprising a crowbar circuit, wherein, in response to detecting the occurrence of a fault, the second upstream switch is operated to interrupt the supply of a DC current / voltage to the power cable, and in response to detecting the occurrence of a fault, the third upstream switch is operated to interrupt the supply of an electrical pulse or a DC current / voltage to the power cable by short-circuiting the upstream source, and When the number of detected fault occurrences satisfies a counting threshold, the first upstream switch is operated to interrupt the supply of DC current / voltage to the power cable and stop the power supply operation.

6. The system according to claim 5, wherein: The at least one controller is further configured to: Before supplying DC current / voltage, controlling the second upstream switch to generate an electrical pulse in a startup phase, Wherein, when an electrical pulse is supplied to the power cable, the at least one controller detects the occurrence of a fault based on measurements from the impedance sensor energy storage circuit, and in response to detecting the occurrence of the fault, does not allow DC current / voltage to be applied to the cable by not closing the second upstream switch.

7. The system according to claim 6, wherein: The at least one controller is further configured to: when no fault occurrence is detected during a startup phase, operating the second upstream switch to provide a DC current / voltage from the source to the power cable, Wherein, when DC current / voltage is supplied to the power cable, the at least one controller detects the occurrence of a fault based on the measurement of electrical activity from the impedance sensor, and in response to detecting the occurrence of the fault, interrupts the supply of DC current / voltage together with the electrical pulses to the power cable using the second and third upstream switches.

8. The system according to claim 1, wherein: The cable comprises a twisted 2-wire cable or a twisted 3-wire cable, the upstream and downstream low pass filters comprise pi filters, and / or power line communication is performed via the power cable.

9. The system according to claim 1, wherein: The fault includes a fault caused by human body contact between lines on the power cable, a fault caused by human body contact between lines on the power cable and ground, a short circuit fault or a resistance fault.

10. The system according to claim 1, wherein: The source is configured to provide an electrical pulse during a start-up phase and then supply a DC current / voltage or a DC current / voltage together with the electrical pulse during steady-state operation.

11. A method of operating a fault managed power system having a source, a downstream component and a power cable for transmitting power from the source to the downstream component, the power cable comprising at least one conductive wire, the method comprising: Isolating the power cable from upstream noise or signals using a low-pass filter upstream of the source, the upstream low-pass filter being connected between the power source and the power cable; Use downstream low-pass filters of downstream components to isolate the power cable from downstream noise or signals; supplying electrical energy from a source to the power cable, including electrical pulses or DC current / voltage together with electrical pulses, the electrical pulses being generated by momentary operation of the source; measuring electrical activity associated with the electrical pulses on the power cable using a sensor, the sensor comprising an impedance sensor tank circuit of a source, the impedance sensor tank circuit disposed between the pulse generator and the power cable; detecting electrical disturbance on the power cable corresponding to occurrence of a fault due to contact of a human body with the power cable based on measurement from an impedance sensor when an electrical pulse or a DC current / voltage together with the electrical pulse is supplied to the power cable; and In response to detecting the occurrence of a fault, the supply of electrical energy to the power cable is interrupted via at least one upstream switch.

12. The method according to claim 11, wherein: The impedance sensor energy storage circuit is configured to sense impedance changes on the power cable or leakage current on the cable. The sensor includes an impedance sensor with RC components and a pi filter with LC components. The capacitor in the impedance sensor and the inductor in the pi filter form an energy storage circuit to amplify the fault signal on the cable.

13. The method according to claim 11, wherein: The at least one upstream switch comprises a switch that is turned on and off to generate electrical pulses by momentary operation of the source.

14. The method according to claim 11, further comprising: converting electrical energy supplied from a power source using an upstream power converter of the source, the upstream power converter being upstream of the upstream low pass filter, and wherein the electrical energy received from the power cable is converted using a downstream low pass filter of the downstream component, the downstream power converter being downstream of the downstream low pass filter; and The converted electrical energy is supplied to downstream loads.

15. The method according to claim 11, wherein: The at least one switch comprises: a first upstream switch; a second upstream switch disposed between the upstream low pass filter and the pulse generator and comprising a solid state switch; and a third upstream switch, disposed between the pulse generator and the sensor and comprising a crowbar circuit, The method further comprises: In response to detecting the occurrence of a fault, operating an upstream second switch to interrupt the supply of a DC current / voltage to the power cable; In response to detecting the occurrence of a fault, operating an upstream third switch to interrupt the supply of DC current / voltage to the power cable by short-circuiting the upstream source; and When the number of detected fault occurrences satisfies a counting threshold, the upstream first switch is operated to interrupt the supply of DC current / voltage to the power cable and stop the power supply operation.

16. The method according to claim 15, further comprising: controlling the second upstream switch to generate an electrical pulse in a start-up phase before supplying the DC current / voltage, Wherein, when an electrical pulse is supplied to the power cable, the detection operation detects the occurrence of a fault based on measurements from the impedance sensor energy storage circuit, and in response to detecting the occurrence of the fault, the interruption operation does not allow DC current / voltage to be applied to the power cable by not closing the second upstream switch.

17. The method according to claim 16, further comprising: when no fault occurrence is detected during a startup phase, operating the second upstream switch to provide a DC current / voltage from the source to the power cable, wherein, when DC current / voltage together with electrical pulses are supplied to the power cable, a detection operation detects the occurrence of a fault based on measurement of electrical activity from the impedance sensor, and in response to detecting the occurrence of the fault, an interruption operation uses second and third upstream switches to interrupt the supply of DC current / voltage and electrical pulses to the power cable.

18. The method according to claim 11, wherein: The power cable includes a twisted 2-wire cable or a twisted 3-wire cable, the upstream and downstream low-pass filters include π filters, and / or power line communication is performed through the power cable.

19. The method according to claim 11, wherein: The fault includes a fault caused by human body contact between lines on the power cable, a fault caused by human body contact between lines on the power cable and ground, a short circuit fault or a resistance fault.

20. The method according to claim 11, wherein: The source is configured to supply electrical pulses during a start-up phase and then supply a DC current voltage or a DC current / voltage together with the electrical pulses during steady-state operation.

Images