A hot-swap circuit for providing soft start and overcurrent protection to an electronic circuit may include a controller and a timer. The controller may be configured to sense an electrical current associated with the hot-swap circuit, based on the electrical current sensed, perform current limiting of the electrical current to minimize inrush current to the electronic circuit, and disable the electrical current from flowing to the electronic circuit in response to the electrical current exceeding an overcurrent threshold for longer than a duration of a fault timer. The timer circuit may be configured to, for a period of time after enabling of the hot-swap circuit, cause the duration of the fault timer to be a first duration, and after the period of time, cause the duration of the fault timer to be a second duration significantly shorter than the first duration.

A device for controlling battery operation includes a battery cell, a thermal cutoff, and a battery management system. The thermal cutoff is coupled in series between the battery cell and a system load of the device. The thermal cutoff has at least three terminals. A first terminal of the thermal cutoff is electrically-coupled to the battery cell and a second terminal of the thermal cutoff is electrically-coupled to the system load. The thermal cutoff includes a permanent failure mechanism having an open state and closed state wherein the closed state allows electrical communication between the first terminal and the second terminal. The battery management system is electrically-coupled to a third terminal of the thermal cutoff. The permanent failure mechanism permanently switches to the open state in response to an electrical signal from the battery management system.

An electronic system for a surgical instrument is disclosed. The electronic system comprises a main power supply circuit configured to supply electrical power to a primary circuit. A supplementary power supply circuit configured to supply electrical power to a secondary circuit. A short circuit protection circuit coupled between the main power supply circuit and the supplementary power supply circuit. The supplementary power supply circuit is configured to isolate itself from the main power supply circuit when the supplementary power supply circuit detects a short circuit condition at the secondary circuit. The supplementary power supply circuit is configured to rejoin the main power supply circuit and supply power to the secondary circuit, when the short circuit condition is remedied.

A current interrupting device includes: a current limiting element provided on a power supply path from a predetermined power supply to a load device, the current limiting element being configured to exhibit a current limiting action when current flowing the power supply path exceeds a first current threshold value; a current diversion path switch capable of switching on and off of an electric conduction of a current diversion path, the current diversion path switch being connected in parallel with the power supply path; and a controller configured to control on and off of the current diversion path switch, wherein, the controller is configured to: switch the current diversion path switch on from an off state when it is detected that current flowing the current limiting element is limited to a second current threshold value after the current flowing the current limiting element has exceeded the first current threshold value; and switch the current diversion path switch off again after a predetermined switched-on holding time has elapsed since the current diversion path switch has been switched on.

An embodiment of the present disclosure relates to an electronic circuit including a first switch coupling a first node of the circuit to an input/output terminal of the circuit; a second switch coupling the first node to a second node of application of a fixed potential; and a highpass filter having an input coupled to the terminal and an output coupled to a control terminal of the second switch.

Systems and methods to estimate trapped charge for a controlled automatic reclose of a power line using a ganged switching device are described herein. For example, an intelligent electronic device (IED) may calculate a voltage amount associated with trapped charge of each phase of a power line based on voltage measurements of the power line. The IED may send a signal to close a ganged switching device at a time based at least in part on the trapped charge of each phase of a power line.

The present disclosure provides a DC mechanical circuit breaker that can utilize two switches, one of which can generate zero-crossing with an alternate oscillatory circuit for the other one, which can be a conventional zero-crossing-based AC breaker and can be used in the main circuit. This is different from the conventional single-switch commute-and-absorb method currently used. The present disclosure shows that disclosed circuit breaker improves the fault current extinction and significantly reduces the voltage rate-of-change while creating the current zero-crossing faster compared to the available technology. Thus, disclosed circuit breaker is capable of interrupting high DC currents with minimal arc through a less expensive AC circuit breaker. Simulation and hardware results are provided to show the efficiency of the disclosed circuit breaker.

A heating device includes a heater, an AC-voltage input section between which an AC voltage is applied, a fuse, a switcher, an AC-voltage-abnormality detector configured to detect an abnormality of the AC voltage, a controller. The controller is configured to execute a current-flowing operation in a state in which connection of a first connection terminal to a second connection terminal is a non-connecting state. The current-flowing operation is an operation in which an electrical current flows through the heater. The controller is configured to execute a connecting process in response to detection of the abnormality of the AC voltage by the AC-voltage-abnormality detector detected in the middle of the current-flowing operation. The connecting process is a process of switching a connection of a first connecting point to a second connecting point from a non-connecting state to a connecting state.

An electrical system forming part of a solar power plant is described. The electrical system includes a plurality of photovoltaic (PV) panels, a power converter, and a controller. In response to a detected electric arc on the DC side of the power converter, the controller is configured to enable a short circuit state of the power converter by controlling semiconductor switches of the power converter (e.g., turning on some or all of the semiconductor switches) to create a short circuit between DC input terminals of the power converter. The short circuit path though the power converter will extinguish the detected electric arc in the connected DC circuit.

A short circuit detection apparatus includes a capacitor connected to a high potential side of a semiconductor switching device via a diode and a resistor connected in series, a short circuit determination circuit that detects a terminal voltage of one terminal of the capacitor, and determines that the semiconductor switching device has short-circuited when the terminal voltage is equal to or greater than a threshold voltage, and a voltage control circuit that is provided between another terminal of the capacitor and a low potential side of the semiconductor switching device, switches between a conduction and an interruption of the capacitor and the semiconductor switching device, and applies an offset voltage between the capacitor and the semiconductor switching device when conducting.