Sensing leakage current in fault management power supply system

Abstract

A fault management power supply system (FMPS) measures leakage current in an electronic circuit. The FMPS includes a source controller, a leakage current sensor, a pulse controller, and a load end circuit. The source controller generates a pulsed input defining a current on-time interval and a current off-time interval. During the current-off time interval, a source driver of the source controller opens the source switch to disconnect power from the power source. A leakage current sensor utilizes a leakage current sensor driver to open a leakage current sensor switch. The pulse controller closes the pulse switch with the pulse driver to provide a return path for the leakage current during the current-off time interval. A holding capacitor at the load-end circuit reversely biases the blocking diode to isolate the load from the electronic circuit such that the leakage current flows in the leakage current sensor, thereby enabling accurate measurement of the leakage current.

Description

Technical Field

[0001] The present invention relates generally to fault-managed power systems and, more particularly, to systems and methods for measuring leakage current in electronic circuits. Background Art

[0002] Fault-managed power systems are configured to monitor and detect predetermined faults and mitigate detected faults in electronic circuits to maintain safe operating conditions for the electronic circuits. For example, a fault-managed power system may be configured to detect leakage current in an electronic circuit as part of ensuring touch-safe operation of the electronic circuit. Typically, fault-managed power systems require complex circuitry to detect leakage current in the electronic circuit, complicating fault detection. Consequently, this complex circuitry increases the time and cost associated with fault-managed power systems.

[0003] Commonly assigned U.S. Patent Publication No. 2023 / 0221380, the entire contents of which are incorporated herein by reference, discloses a fault management power system that can be used to detect fault conditions in electronic circuits. Summary of the Invention

[0004] Aspects of the present invention allow for an efficient framework for accurately measuring leakage current in electronic circuits.

[0005] In one aspect, a fault-managed power supply system is configured to measure leakage current in an electronic circuit. The fault-managed power supply system includes a source controller electrically connected to the electronic circuit and configured to generate a pulse input. The pulse input includes a series of pulses, each pulse including a current-off interval and a current-on interval at a predetermined rate. The source controller includes a source driver and a source switch. The source driver is operably connected to the source switch. The source driver is configured to open and close the source switch based on the pulse input to control the supply of power from the power supply to the electronic circuit during the current-on and current-off intervals. A leakage current sensor is electrically connected to the electronic circuit. The leakage current sensor includes a leakage current sensor driver and a leakage current sensor switch. The leakage current sensor switch is operably connected to the leakage current sensor. The leakage current sensor driver is operably connected to the source controller and the leakage current sensor switch. The leakage current sensor driver is configured to open and close the leakage current sensor switch based on the pulse input received from the source controller. The leakage current sensor is configured to measure leakage current in the electronic circuit during the current-off interval. The pulse controller is electrically connected to the electronic circuit. The pulse controller includes a pulse driver and a pulse switch. The pulse switch is operably connected to the leakage current sensor. A pulse driver is operably connected to the source controller and the pulse switch. The pulse driver is configured to close and open the pulse switch based on a pulse input received from the source controller. The pulse switch provides a return path for leakage current during a current-off interval. A load-side circuit is electrically connected to the electronic circuit and the load. The load-side circuit includes a blocking diode and a holding capacitor electrically connected in series with the blocking diode. The holding capacitor is configured to reverse bias the blocking diode during the current-off interval to isolate the load from the electronic circuit, allowing leakage current to flow into the leakage current sensor, thereby enabling accurate measurement of leakage current in the electronic circuit.

[0006] In another aspect, a method for measuring leakage current in an electronic circuit includes detecting a current disconnection time interval based on a pulse input received from a source controller. A source switch of the source controller is opened to prevent power from being supplied to the electronic circuit from a power source during the current disconnection time interval. A pulse switch electrically connected to the electronic circuit is closed to provide a return path for the leakage current during the current disconnection time interval. A blocking diode electrically connected to the electronic circuit and a load is reverse-biased with a holding capacitor to isolate the load from the electronic circuit, and the holding capacitor is electrically connected in series with the blocking diode. A leakage current sensor switch electrically connected to the electronic circuit is opened, causing leakage current to flow in a leakage current sensor electrically connected to the electronic circuit, thereby enabling accurate measurement of the leakage current in the electronic circuit. During the current disconnection time interval, the leakage current in the electronic circuit is measured using the leakage current sensor.

[0007] Other objects and features will be in part apparent and in part pointed out hereinafter. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 is a schematic block diagram of a fault management power supply system for electronic circuits according to an embodiment.

[0009] Figure 2 Another fault management power supply system according to an embodiment is shown.

[0010] Figure 3 Another fault management power supply system according to an embodiment is shown.

[0011] Figure 4 is a flow chart of an exemplary method for measuring leakage current in an electronic circuit according to an embodiment.

[0012] Corresponding reference characters indicate corresponding parts throughout the several views of the drawings. DETAILED DESCRIPTION

[0013] A fault managed power system (FMPS) provides a system and method for safely transmitting power. Suitably, the FMPS is configured to monitor electronic circuits for fault conditions and to limit available power during a detected fault event to prevent a hazard. FMPS are particularly useful in power-supply systems because they can operate at a maximum line-to-line source voltage of up to 450 Vdc. In addition, FMPS are subject to strict standards for personal safety in the event of accidental human contact with power cables carrying electronic circuits.

[0014] One difficulty with current FMPSs is detecting leakage current in electronic circuits. In particular, the load connected to the electronic circuit can interfere with the measurement and detection of leakage current. To counteract this interference, existing FMPSs require complex circuitry at the load end of the electronic circuit, increasing the cost, manufacturing, and operating time associated with the FMPS. In contrast, aspects of the present disclosure provide an improved FMPS and method thereof for simple, accurate, and more efficient monitoring of leakage current within electronic circuits, as explained in more detail below.

[0015] Now refer to Figure 1A fault managed power system (FMPS) according to the present invention is generally indicated by reference numeral 100. FMPS 100 is configured to measure and detect leakage current in an electronic circuit. Furthermore, FMPS 100 is configured to shut off power from a power source 102 electrically connected to the electronic circuit upon detecting a leakage current exceeding a predetermined threshold. Broadly speaking, FMPS 100 includes a source controller 104, a pulse controller 106, a leakage current sensor 108, and a load-side circuit 110. A pulse generator 112 of source controller 104 is configured to generate a pulse input comprising a series of pulses at a predetermined rate. These pulses define a current-off interval and a current-on interval. During the current-off interval, source controller 104 is configured to shut off power from power source 102 to measure leakage current in the electronic circuit. Furthermore, load-side circuit 110 is configured to isolate a load 114 electrically connected to the electronic circuit to prevent interference with leakage current measurements. Before turning to an exemplary method for measuring leakage current using the FMPS, the various components of FMPS 100 will now be described in more detail.

[0016] In a non-limiting embodiment, the electronic circuit is electrically coupled to a power source 102 and configured to supply power from the power source 102 along a cable 116 to a load 114. The power source 102 may include an AC or DC power source, typically derived from an AC power mains supply. In one example, the power source 102 includes a possible voltage range of up to 1000 volts, but typically between 100 volts and 450 volts (e.g., V1 = 100 volts to 450 volts). Examples of cables 116 according to the present disclosure include Class 4 cables and power fiber optic cables (PFC). In one embodiment, the cable 116 includes a pair of conductors, typically copper, and typically arranged as a twisted pair. For example, the cable 116 has characteristics similar to an AWG 12-2 cable. The load 114 may include an electrical device electrically coupled to the electronic circuit via the cable 116.

[0017] The source controller 104 is electrically coupled to the electronic circuitry and configured to generate a pulse input comprising a series of pulses at a predetermined rate. For example, the source controller 104 includes a pulse generator 112, such as an oscillator, for generating the pulse input. The predetermined rate at which the pulse generator 112 generates the pulse input allows the system to respond quickly enough to prevent ventricular fibrillation (VF) and typically produces a very slight sensation, known as a touch-safe level, before shutting off the voltage on the leads. In other words, to maintain touch-safe operation, the energy supplied to the human body must remain below a release level. To this end, the FMPS 100 is equipped with the ability to detect when the current level exceeds a level considered touch-safe during a specific time interval, as will be explained in more detail below.

[0018] At the source controller 104, a non-touch safety current is detected by monitoring a pulse input on the cable 116. Each pulse input includes a current-on interval and a current-off interval at a predetermined rate. The current-on interval corresponds to a period during which current flows from the power supply 102 along the cable 116, through the electronic circuit, and into the load 114. The current-off interval corresponds to a period during which no current flows from the power supply 102. During the current-off interval, the current on the cable 116 typically decays toward zero at a rate dependent on the system time constant. If a person makes contact with the cable 116, causing a leakage current fault condition, current will flow due to the path provided by the person's contact with the conductor. This causes the current on the cable 116 to be non-zero during the current-off interval after the transient decays. If the current remains above a predetermined threshold after the system transient time constant has elapsed, this indicates that a non-touch safety current level may be present. As described in more detail below, upon detecting such a non-touch safety current level, the source controller 104 is configured to immediately shut off power from the power supply 102 to limit the energy delivered to the person. More specifically, the energy provided to a person is limited to the energy stored in the cable 116, which is designed to be below a shock and fire hazard level.

[0019] The source controller 104 also includes a source driver D1 and a source switch S1. The source driver D1 is operably connected to the source switch S1 and is configured to open and close the source switch according to a pulse input to connect or disconnect power to the power supply 102. For example, during a current-on interval, the source driver D1 is configured to close the source switch S1 to supply power from the power supply 102 to the electronic circuit. During a current-off interval, the source driver D1 is configured to open the source switch S1 so that no power is supplied from the power supply 102 to the electronic circuit.

[0020] In one example, the source switch S1 comprises a high-power MOSFET switch. Preferably, the source switch S1 comprises an N-channel enhancement mode SiC MOSFET switch, but other types of semiconductor switches may also be used. The specific type of semiconductor switch used largely determines the design of the source driver D1. Generally speaking, switches with faster turn-on times are preferred to minimize switching losses. However, depending on the inductance of the cable 116 and the switch turn-off time, the fast turn-on time may cause transient overvoltages, which may require transient overvoltage protection. Transient overvoltage protection can be achieved by placing a snubber (such as a diode) and a variable resistor (such as a metal oxide varistor (MOV)) across the source switch S1 to clamp the transient overvoltage at a predetermined level. It is also desirable to have a switch with low on-resistance to reduce conduction losses.

[0021] In one example, source driver D1 is a discrete gate driver. As described above, the type of semiconductor switch used for source switch S1 largely determines the type of driver D1. An example driver that can be used includes the third generation (CM3) SiC MOFSET part number CGD15SG00D2 available from Wolfspeed, Inc. However, source driver D1 can be integrated with another component, such as within source controller 104.

[0022] The pulse controller 106 is electrically connected to the electronic circuitry and includes a pulse driver D2 and a pulse switch S2. The pulse driver D2 is operably connected to the source controller 104 and the pulse switch S2. Furthermore, the pulse driver D2 is configured to close and open the pulse switch S2 based on a reverse pulse input received from the source controller 104. For example, the pulse driver D2 is configured to open the pulse switch S2 during the current-on interval. Furthermore, the pulse driver D2 is configured to close the pulse switch S2 during the current-off interval, such that the pulse switch provides a return path to the return conductor for leakage current during the current-off interval. In the illustrated embodiment, the pulse controller 106 also includes a resistor and a capacitor electrically connected to the electronic circuitry for efficient operation of the FMPS 100. As shown, the resistor of the pulse controller 106 is electrically connected in series with the pulse switch S2, and the capacitor of the pulse controller 106 is electrically connected in parallel with the resistor and the pulse switch S2.

[0023] In one example, the pulse switch S2 comprises a high-power MOSFET switch. Preferably, the pulse switch S2 comprises an N-channel enhancement mode SiC MOSFET switch, but other types of semiconductor switches may also be used. The specific type of semiconductor switch used largely determines the design of the pulse driver D2. Generally speaking, switches with faster turn-on times are preferred to minimize switching losses. However, depending on the inductance of the cable 116 and the switch turn-off time, the fast turn-on / off times may cause transient overvoltages, which may require transient overvoltage protection. Transient overvoltage protection can be achieved by placing a snubber (such as a diode) and a variable resistor (such as a metal oxide varistor (MOV)) across the pulse switch S2 to clamp the transient overvoltage at a predetermined level. It is also desirable to have a switch with low on-resistance to reduce conduction losses.

[0024] In one example, pulse driver D2 is a discrete gate driver. As described above, the type of semiconductor switch used for pulse switch S2 largely determines the type of driver D2. An example driver that can be used includes part number CGD15SG00D2 of a third generation (CM3) SiC MOFSET available from Wolfspeed, Inc. However, pulse driver D2 can be integrated with another component, such as within source controller 104.

[0025] Leakage current sensor 108 is electrically connected to the electronic circuit and includes a leakage current sensor driver D3 and a leakage current sensor switch S3. Leakage current sensor switch S3 is operably connected to leakage current sensor 108. Leakage current sensor driver D3 is operably connected to source controller 104 and leakage current sensor switch S3. Leakage current sensor driver D3 is configured to open and close leakage current sensor switch S3 based on a pulse input received from source controller 104. For example, leakage current sensor driver D3 is configured to close leakage current sensor switch S3 during a current-on interval and open leakage current sensor switch S3 during a current-off interval. Furthermore, leakage current sensor 108 is configured to measure leakage current in the electronic circuit during the current-off interval. For example, leakage current sensor 108 is configured to detect leakage current as part of ensuring touch-safe operation of the electronic circuit. Leakage current sensor 108 is configured to detect small currents on the order of 1 mA to 100 mA.

[0026] In one example, leakage current sensor 108 includes an operational amplifier and a leakage sensing resistor connected to the input of the operational amplifier. The output of leakage current sensor 108 is connected to source controller 104, and in one example, specifically to its A / D converter. Leakage current sensor switch S3 is connected to the input of the operational amplifier and is used to shunt current around sink leakage current sensor 108 during the current-on interval, so that sink leakage current sensor 108 only detects current during the current-off interval. During the current-off interval, source controller 104 controls leakage current sensor driver D3 to turn off (disconnect) source switch S1 in synchronization with the turning off (disconnection) of leakage current sensor switch S3.

[0027] In one example, leakage current sensor switch S3 is an N-channel SiC MOSFET with a low drain-source resistance of approximately 5mΩ and a voltage rating of 100V. Furthermore, the design of leakage current sensor 108 should take into account the common-mode voltage rating because the leakage sense resistor is located at the high side of power supply 102. Therefore, the operational amplifier must either be rated for the full voltage across the input capacitor or left floating. The leakage sense resistor consumes virtually no power because the rated circuit current (e.g., approximately 2 to 16A) does not flow through it during the current-off interval.

[0028] Load-side circuit 110 is electrically connected to the electronic circuit and load 114. In the illustrated embodiment, load-side circuit 110 is electrically connected to the electronic circuit via cable 116. Load-side circuit 110 includes a blocking diode 118 and a holding capacitor 120 electrically connected in series with the blocking diode. Holding capacitor 120 is configured to reverse bias blocking diode 118 during a current-off interval to isolate load 114 from the electronic circuit, allowing leakage current to flow through leakage current sensor 108, thereby enabling accurate measurement of leakage current in the electronic circuit. Therefore, the simple design of load-side circuit 110 provides a simple, cost-effective solution for reducing the circuit complexity of an FMPS.

[0029] Now refer to Figure 2 , shows an exemplary embodiment of a fault management power supply system 200 according to the present invention. In particular, the FMPS 200 is shown as including at least one of the same and similar components as described above, as well as an inrush current limiter 202. As shown, the inrush current limiter 202 is electrically connected to the electronic circuit and the power supply 102. The inrush current limiter 202 is configured to limit the inrush current from the power supply 102 during the current on time interval. Figure 2 In order to reduce the complexity of the receiver circuit, the blocking diode D and the holding capacitor C L Used with the voltage balancing circuit for loads to ensure that no current flows during the current disconnection interval in the absence of a fault on the cable 116. The voltage balancing circuit dissipates the current by consuming capacitor C B The voltage across the diode D is used to ensure that the diode D is reverse biased during the off interval.

[0030] exist Figure 2 In the example:

[0031] During the current disconnection interval

[0032] During the current disconnection interval

[0033] During the current off time interval V L >V cable -V D

[0034] If V Leak > V threshold , cut off the source switch

[0035] Determine C based on the load impedance L size

[0036] Reference Figure 3, shows an exemplary embodiment of an FMPS 300. In particular, the FMPS 300 is shown as including at least one component that is the same or similar to that described above. However, Figure 3 A schematic representation of the fault state is also provided to illustrate how the leakage current will change from a non-fault state to a fault state when human contact is made. Furthermore, closing switch S4 represents a person touching across the line, and the resistor represents the person's resistance when current flows through the body to ground rather than through the load 114.

[0037] exist Figure 3 In the example:

[0038] During the current disconnection interval

[0039] During the current disconnection interval

[0040] During the current off time interval V L >V cable -V D

[0041] Approximately (ignoring IR cable voltage drop and diode voltage drop) Z L C L >R B C B

[0042] If V Leak > V threshold , cut off the source switch

[0043] The fault management power system described above is configured for measuring leakage current in an electronic circuit. An exemplary method of using the fault management power system will now be described.

[0044] The method begins with the operation of pulse generator 112. Pulse generator 112 generates a pulse input comprising a series of pulses at a predetermined rate, such that each pulse includes a current-on interval and a current-off interval. As described above, the pulse input is generated at a predetermined rate that is lower than a rate that would prevent a person from releasing the energized cable and cause an electric shock during the pulse. Source controller 104 is configured to provide the pulse input to source driver D1, pulse driver D2, and leakage current sensor driver D3 to determine an action.

[0045] Reference Figure 4, the FMPS 100 performs method 400 based on the pulse input. At step 402, the FMPS operates in a current disconnection time interval or a current connection time interval determined by the source controller 104. During the current disconnection time interval, the method proceeds to step 404, where the source driver D1 opens the source switch S1 to prevent power from being supplied to the electronic circuit from the power supply 102 during the current disconnection time interval. In addition, the leakage current sensor driver D3 opens the leakage current sensor switch S3 to allow current to flow into the leakage current sensor 108. At step 406, the pulse driver D2 in response to the reverse pulse signal closes the pulse switch S2 to provide a path for the leakage current to the return conductor during the current disconnection time interval. At step 408, the holding capacitor 120 reverse biases the blocking diode 118 to isolate the load 114 from the electronic circuit because the voltage across the holding capacitor 120 is designed to be greater than the storage capacitor C B The voltage across the terminal (VB) is measured at step 410. Next, the leakage current sensor 108 measures the leakage current and provides the measurement result as an output to the source controller 104. Then, at step 412, the source controller 104 determines whether the leakage current sensor 108 detects any leakage current. If no leakage current is detected, the method proceeds to step 426, where a zero measurement value is recorded in the system database. In one embodiment, the source controller 104 is configured to communicate with the system database to record the measurement result. Otherwise, the method proceeds to step 414.

[0046] At step 414, the detected leakage current is recorded in the system database. Next, at 416, the source controller 104 determines whether the detected leakage current is greater than a predetermined threshold. In another embodiment, the source controller 104 further determines whether the detected leakage current remains greater than the predetermined threshold for a predetermined amount of time. If the determination is yes in either case, the method proceeds to step 418. At step 418, the source controller 104 is configured to shut off power to the power supply 102 within the predetermined amount of time to prevent fire and safety hazards.

[0047] Referring back to step 402, if the pulse input indicates a current on-time interval, then at step 420, source driver D1 closes source switch S1 to supply power from power supply 102 to the electronic circuit. Furthermore, leakage current sensor driver D3 closes leakage current sensor switch S3, and pulse driver D2 opens pulse switch S2 at step 422. Thus, at step 424, power is supplied to load 114 along cable 116.

[0048] Embodiments of the present invention include special-purpose computers comprising various computer hardware, as described in more detail herein, which, even though described in conjunction with an example computing system environment, may also operate with other special-purpose computing system environments or configurations. The computing system environment is not intended to impose any limitations on the scope of use or functionality of any aspect of the present invention. Furthermore, the computing system environment should not be interpreted as imposing any dependency or requirement on any one component or combination thereof shown in the example operating environment. Examples of computing systems, environments, and / or configurations suitable for use in various aspects of the present disclosure include, but are not limited to, personal computers, server computers, handheld or laptop devices, multiprocessor systems, microprocessor-based systems, set-top boxes, programmable consumer electronics, mobile phones, network PCs, minicomputers, mainframe computers, distributed computing environments including any of the above systems or devices, and the like.

[0049] Aspects of the present invention may be described in the general context of data and / or processor executable instructions, such as program modules, stored in one or more tangible, non-transitory storage media and executed by one or more processors or other devices. Typically, program modules include, but are not limited to, routines, programs, objects, components, and data structures that perform specific tasks or implement specific abstract data types. Aspects of the present disclosure may also be implemented in a distributed computing environment, where tasks are performed by remote processing devices linked through a communication network. In a distributed computing environment, program modules may be located in local and remote storage media including memory storage devices. For illustrative purposes, programs and other executable program components may be shown as discrete blocks. However, it should be recognized that these programs and components reside in different storage components of a computing device at different times and are executed by the data processor of the device.

[0050] In operation, a processor, computer, and / or server may execute processor-executable instructions (e.g., software, firmware, and / or hardware), as described herein, to implement aspects of the present invention. The processor-executable instructions may be organized into one or more processor-executable components or modules on a tangible processor-readable storage medium. Furthermore, embodiments may be implemented with any number and organization of such components or modules. For example, aspects of the present disclosure are not limited to the specific processor-executable instructions or specific components or modules shown in the accompanying drawings and described herein. Other embodiments may include different processor-executable instructions or components having more or less functionality than shown and described herein.

[0051] According to the various aspects of the present invention shown and described herein, the order in which operations are performed or implemented is not important unless otherwise specified. That is, operations can be performed in any order, unless otherwise specified, and embodiments may include more or fewer operations than those disclosed herein. For example, it is contemplated that performing or implementing a particular operation before, simultaneously with, or after another operation is within the scope of this disclosure.

[0052] Not all components shown or described are required. Furthermore, some implementations and embodiments may include additional components. The arrangement and type of components may be varied without departing from the spirit or scope of the claims set forth herein. In addition, different or fewer components may be provided, and components may be combined. Alternatively or additionally, a component may be implemented by several components.

[0053] Having described the invention in detail, it will be apparent that modifications and variations are possible without departing from the scope of the invention as defined in the appended claims.

[0054] When introducing elements of the present invention or the preferred embodiment(s) thereof, the articles "a," "an," "the," and "said" are intended to mean that there are one or more of the elements. The terms "comprising," "including," and "having" are intended to be inclusive and mean that there may be additional elements other than the listed elements.

[0055] In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

[0056] As various changes could be made in the above product without departing from the scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

[0057] The Abstract and Summary are provided to help the reader quickly ascertain the nature of the technical disclosure. They are submitted with the understanding that they will not be used to interpret or limit the scope or meaning of the claims. This Summary is provided to introduce some concepts that are further described in the Detailed Description in a simplified form. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the claimed subject matter.

Claims

1. A fault management power supply system configured to measure leakage current in an electronic circuit, the fault management power supply system comprising: a source controller electrically connected to the electronic circuit and configured to generate a pulse input, the pulse input comprising a series of pulses, each pulse comprising a current-off time interval and a current-on time interval at a predetermined rate, the source controller comprising a source driver and a source switch, the source driver operatively connected to the source switch, the source driver configured to open and close the source switch in accordance with the pulse input to control the supply of power from a power source to the electronic circuit during the current-on and current-off time intervals; a leakage current sensor electrically connected to the electronic circuit, the leakage current sensor comprising a leakage current sensor driver and a leakage current sensor switch operatively connected to the leakage current sensor, the leakage current sensor driver operatively connected to the source controller and the leakage current sensor switch, the leakage current sensor driver configured to open and close the leakage current sensor switch based on a pulse input received from the source controller, the leakage current sensor configured to measure leakage current in the electronic circuit during the current disconnection time interval; a pulse controller electrically connected to the electronic circuit, the pulse controller comprising a pulse driver and a pulse switch, the pulse switch operatively connected to the leakage current sensor, the pulse driver operatively connected to the source controller and the pulse switch, the pulse driver configured to close and open the pulse switch based on a pulse input received from the source controller, the pulse switch providing a return path for the leakage current during the current disconnection time interval; and a load-side circuit electrically connected to the electronic circuit and the load, the load-side circuit comprising a blocking diode and a holding capacitor electrically connected in series with the blocking diode, wherein the holding capacitor is configured to reverse bias the blocking diode during the current-off time interval to isolate the load from the electronic circuit, allowing leakage current to flow in the leakage current sensor, thereby enabling accurate measurement of the leakage current in the electronic circuit.

2. The fault management power supply system according to claim 1, wherein: The source controller includes a pulse generator for generating a pulse input.

3. The fault management power supply system according to claim 2, wherein: The pulse generator includes an oscillator.

4. The fault management power supply system of claim 1, wherein: The predetermined rate is below a rate that would cause a person to be unable to release the shock and enter ventricular fibrillation.

5. The fault management power supply system of claim 1 , wherein: The source driver is configured to close the source switch during a current-on time interval to supply power from the power supply to the electronic circuit, and wherein the source driver is configured to open the source switch during a current-off time interval so that no power is supplied from the power supply to the electronic circuit.

6. The fault management power supply system of claim 1, wherein: The leakage current sensor driver is configured to close the leakage current switch during a current-on time interval and to open the leakage current switch during a current-off time interval.

7. The fault management power supply system of claim 1, wherein: The leakage current sensor also includes at least one of an operational amplifier and a leakage sensing resistor.

8. The fault management power supply system of claim 1, wherein: The pulse driver is configured to open the pulse switch during a current-on time interval and close the pulse switch during a current-off time interval.

9. The fault management power supply system of claim 1, wherein: The pulse controller further includes at least one of a resistor and a capacitor.

10. The fault management power supply system of claim 1, wherein: The load-side circuit is electrically connected to the electronic circuit via a cable, and the source driver is configured to open and close the source switch according to the pulse input during a current-on time interval to provide power from the power source to the electronic circuit and the load along the cable.

11. The fault managed power supply system of claim 1 , further comprising an inrush current limiter electrically connected to the electronic circuit and the power supply, the inrush current limiter configured to limit inrush current from the power supply during the current on time interval.

12. A method for measuring leakage current in an electronic circuit, the method comprising: detecting a current disconnection time interval based on a pulse input received from a source controller; opening a source switch of the source controller to prevent power from being supplied to the electronic circuit from the power source during the current disconnection time interval; closing a pulse switch electrically connected to the electronic circuit to provide a return path for the leakage current during the current off time interval; reverse biasing a blocking diode electrically connected to the electronic circuit and the load with a holding capacitor to isolate the load from the electronic circuit, the holding capacitor being electrically connected in series with the blocking diode; and turning on a leakage current sensor switch electrically connected to the electronic circuit so that leakage current flows in the leakage current sensor electrically connected to the electronic circuit, thereby enabling accurate measurement of the leakage current in the electronic circuit; During the current-off time interval, the leakage current in the electronic circuit is measured with a leakage current sensor.

13. The method of claim 12, further comprising generating a pulse input at a predetermined rate, the pulse input comprising a series of pulses, each pulse comprising a current-off time interval and a current-on time interval at the predetermined rate.

14. The method according to claim 12, wherein: The predetermined rate is below a rate that would cause a person to be unable to release the shock and enter ventricular fibrillation.

15. The method of claim 12, further comprising recording leakage current measurements of the electronic circuit in a system database.

16. The method of claim 12, further comprising comparing the leakage current measurement to a predetermined threshold to determine whether the leakage current measurement meets or exceeds the predetermined threshold.

17. The method of claim 16, further comprising opening the source switch for a predetermined amount of time to prevent power from being supplied from the power supply to the electronic circuit if the leakage current measurement meets or exceeds the predetermined threshold.

18. The method of claim 12, further comprising detecting a current on-time interval based on a pulse input received from the source controller and refraining from measuring a leakage current in the electronic circuit.

19. The method according to claim 18, wherein The inhibiting during a current-on time interval further includes closing the source switch to supply power from the power supply to the electronic circuit, closing the leakage current sensor switch, and opening the pulse switch.

20. The method of claim 19, further comprising supplying power from the electronic circuit to the load along a cable electrically connected to the electronic circuit during the current on time interval.

21. A computer-readable medium having stored thereon instructions for causing a computing device to perform a method for measuring leakage current in an electronic circuit, the method comprising: detecting a current disconnection time interval based on a pulse input received from a source controller; reverse biasing a blocking diode electrically connected to the electronic circuit and the load with a holding capacitor to isolate the load from the electronic circuit, the holding capacitor being electrically connected in series with the blocking diode; turning on a leakage current sensor switch electrically connected to the electronic circuit so that leakage current flows in the leakage current sensor electrically connected to the electronic circuit, thereby enabling accurate measurement of the leakage current in the electronic circuit; measuring leakage current in the electronic circuit with a leakage current sensor during a current-off time interval; and comparing the leakage current measurement to a predetermined threshold to determine whether the leakage current measurement meets or exceeds the predetermined threshold; and If the leakage current measurement meets or exceeds a predetermined threshold, the source switch is opened for a predetermined amount of time to prevent power from being supplied to the electronic circuit from the power supply.

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