Systems and methods for health monitoring and fault detection in power distribution networks are provided. Aspects include providing a first power supply coupled to a power channel, providing a load coupled to the power channel, providing a transmitting sensor coupled to the power channel between the first power supply and the load, providing a receiving sensor coupled to the power channel between the transmitting sensor and the load, operating the transmitting sensor to provide an AC test signal to the power channel, the AC test signal comprises a predefined test signal pattern, operating the receiving sensor to sense, from the power channel, a continuous power signal including the AC test signal, analyzing, by the controller, the AC test signal to determine a fault of the power channel based on comparing the predefined test signal pattern with a predefined nominal probe signal pattern corresponding to a specific network configuration.

Systems and methods for testing a lightning protection circuit are provided. Aspects include providing an alternating current (AC) test signal source coupled to a circuit under test, the circuit under test comprising a lightning protection circuit having a threshold voltage, a first filter, and a second filter, providing a direct current (DC) voltage supply in series with a filtering device, the filtering device coupled to the AC test signal source, providing a first capacitor coupled between the AC test signal source and the circuit under test, operating the DC voltage supply and the AC test signal source to provide a first test signal to the circuit under test, wherein the first test signal comprise a first voltage that exceeds the threshold voltage, measuring a first impedance of the circuit under test responsive to providing the first test signal, wherein the first impedance corresponds to the first filter.

A system topology may use intentional signal injection to monitor one or more power supply circuits that may supply electrical power to components of the system. The system topology may include voltage monitoring circuitry to monitor the output of the power supply. In some examples, a power supply rail fault may happen either inside or outside of the power supply circuit, but not be detectable by the voltage monitoring circuitry. Injecting a check signal in the presence of an actual fault, may cause oscillations at the output node of the power supply detectable by the voltage monitoring circuitry. Once the check signal, combined with the fault signal, at the output node reaches the monitoring threshold detectable by the voltage monitoring circuitry, the voltage monitoring circuitry may output an indication of the fault to processing circuitry of the system.

A current leakage detector for detecting current leakage between a power source and a load including a first sensing coil and a second sensing coil positioned opposite the first sensing coil. The current leakage detector further includes a magnetic field sensor proximate the first sensing coil and the second sensing coil and the magnetic field sensor has a response range. The current leakage detector also includes a bias circuit configured to adjust the response range of the magnetic field sensor. A method for detecting current leakage includes providing a first sensing coil and a second sensing coil. The method continues with the steps of providing a magnetic field sensor in proximity to the first and second sensing coils and providing a bias circuit. The method continues with the step of utilizing the bias circuit to place the response of the magnetic field sensor within a preferred response range.

A fault detector detects grounded-neutral faults. The fault detector is configured to: receive a first signal from a first induction circuit, the first induction circuit configured to detect a current imbalance between a line conductor and a neutral conductor; determine a first frequency and a first phase of a noise signal component of the first signal; output a noise cancellation signal to a primary side of the first induction circuit, the noise cancellation signal having the first frequency of the noise signal component and an opposite phase than the first phase of the noise signal component; and generate a trip signal based on determining that an impedance of the neutral conductor to ground is at or below a threshold level based upon the first signal received during the injection of the noise cancelation signal.

Aspects of the disclosure provide for a circuit. In some examples, the circuit includes a first current source having a terminal coupled to a first node and a second terminal, a first switch coupled between the second terminal of the first current source and a second node, a first resistor coupled between the second node and a ground terminal, a second current source having a terminal coupled to the first node and a second terminal, a second switch coupled between the second terminal of the second current source and a third node, a second resistor coupled between the third node and the ground terminal, a third current source having a terminal coupled to the first node and a second terminal, a third switch coupled between the second terminal of the third current source and a fourth node, and a third resistor coupled between the fourth node and the ground terminal.

An object of the present invention is to provide a semiconductor device that can enhance the safety when feeding to a USB device.

Provided is a semiconductor device including: a first power source circuit that generates an output voltage supplied to a USB device coupled to a USB connector; an abnormality detection circuit that determines the state of a supply route of the output voltage generated by the first power source circuit; and a control circuit that controls supply of the output voltage from the first power source circuit to the USB device on the basis of a determination result of the abnormality detection circuit.

A fault detection and isolation system for distribution electric power lines utilizing a remote reference voltage signal, multiple three-phase current monitors producing asynchronous event data, and a common reference clock. A voltage measurement obtained for a power line at a substation may be synchronized with multiple current phase measurements taken at a power monitoring location along that particular power line. The same voltage measurement may be similarly synchronized with current measurements taken at multiple current monitoring locations along the power line. As a result, the same voltage measurement may be synchronized with current measurements taken multiple tap points along the power allowing a fault on a tapped line segment to be identified, located and isolated. An alternative embodiment utilizes differential current analysis utilizing current measurements from adjacent current monitoring locations correlated to a common reference clock to locate faults and therefore does not require a voltage measurement.

Protection circuitry configured to protect an electrical load from both overvoltage and overcurrent and includes a recovery period timer configured to set a recovery time. The recovery time allows a system, including a power supply, voltage regulator, protection circuitry and electrical load to dissipate heat and reset components. The protection circuitry is configured to monitor downstream performance of the electrical load and disconnect upstream power based on a downstream failure or other performance characteristics. The protection circuitry may include a downstream overvoltage sensing circuit that controls a current source. The current source injects current into an overcurrent protection loop in the protection circuitry that includes the configurable recovery period timer. In this manner both an overvoltage and an overcurrent event may take advantage of the configurable recovery period timer without the need for a separate time delay circuit.

A system and method for controlling microgrids composed of inverter-based distributed generation (IBDG) units. This includes a method using multiple IBDGs to inject impedance-modulated harmonic currents during fault conditions, with each IBDG injecting a unique, differentiable harmonic (i.e., non-fundamental) order from neighboring IBDGs. The method also involves using an inverse time-harmonic-current characteristic to detect faults by locally measuring the harmonic currents injected by IBDGs. A harmonic directional overcurrent relay is also used for fault detection.