Solid-state circuit breakers and method of operating same are provided. A solid-state circuit breaker (SSCB) is configured to generate a first output representative of a current through a current path of the SSCB. An analog fault detection circuit is coupled with first output and is configured to assert a second output in response to the current exceeding a trip current level. At least one analog-to-digital converter (ADC) is configured to generate samples of the first output, where the at least one ADC has a di/dt detection bandwidth that is less than a di/dt detection bandwidth of the analog fault detection circuit. The SSCB is further configured to disable the current path through the SSCB in response to determining, asynchronously, that either the second output is being asserted by the analog fault detection circuit or the samples indicate that the current through the current path exceeds the trip current level.

Systems, apparatuses, and methods are described for a circuit breaker. In some examples, control circuitry may be configured to receive sensor data related to a measured current through a first circuit breaker, determine available current based on the received measurement and a maximum current rating, and set a current trip value for the second circuit breaker according to the determined available current. In some examples, control circuitry may be configured to determine a direction of current, control the circuit breaker based on a first threshold when the current is in a first direction, and control the circuit breaker based on a second threshold when the current is in a second direction.

An overcurrent protection device is for protecting a load arranged in a DC grid. The load is coupled to a supply busbar, which is connectable to a supply potential of the DC grid, in the DC grid via the overcurrent protection device. The overcurrent protection device is designed to ascertain a current trigger value based upon a detected value of a current flowing through the overcurrent protection device and a trigger characteristic which is assigned to the load and is based on the current; compare the current trigger value with a threshold, and either trigger the overcurrent protection device or not, based upon the result of the comparison. The current is taken into consideration together with a first or a second factor in the trigger characteristic based upon the current direction.

An electronic apparatus includes: a power supply circuit that supplies power supply voltage to a load; an overcurrent detection circuit that performs output of detection information indicating the direction of current at a power supply path for the load in the power supply circuit when overcurrent occurs in the power supply path; and a determination circuit that performs output of notification information indicating whether or not a location at which a failure occurs exists within the power supply circuit or outside the power supply circuit, based on the detection information.

A switching system for breaking a current, including a contact arrangement having a first and second terminals, a resonance circuit connectable across the contact arrangement, In the closed state the first switch enables current to flow through the resonance circuit in a first flow direction and into the contact arrangement in a direction opposite to a contact arrangement arc current flow direction. A second switch connected to the resonance circuit and to the second terminal. In the closed state the second switch enables current to flow through the resonance circuit in a second flow direction opposite to the first flow direction. A control system arranged to alternatingly set the first and second switches in the closed state and then in the open state upon a current breaking operation, until a current pulse, emanating from energy supplied by a contact arrangement arc current, flowing through the resonance circuit and into the contact arrangement reaches an amplitude which is equal to or greater than a magnitude of a contact arrangement arc current.

A method for detecting faults in a low voltage three-phase network including: checking if any of three phases of the three-phase network satisfies first conditions for a predetermined duration of time; if at least two phases satisfy the first conditions, detecting an inter-phase fault by checking if the current level in at least two phases exceed a threshold and if the corresponding current flows are in the same direction; if only one of the three phases satisfies the first conditions, for the phase which has satisfied the first conditions, checking if a second condition is satisfied and, in a positive case, detecting a mono-phase fault.

A multidirectional electrical power protection system, includes a first power supply and at least a second power supply with each supply being configured for supplying power to a main bus circuit; a first load bus electrically connected to the first power supply and at least the second power supply, at least a second load bus electrically coupled with each of the first power supply and at least the second power supply, the first load bus and the second load bus configured for energizing devices connected to the respective first and second load bus; and at least one smart contactor in coupled with the main bus circuit, the at least one smart contactor being configured for sensing a first current flowing in a first direction through the main bus circuit and for sensing a second current flowing in a second direction through the main bus circuit.

A direct current (DC) solid state circuit breaker includes a first terminal, a second terminal, a power electronics section comprising at least a first transistor switch, and one or more airgap sections that include at least a second transistor switch and a third transistor switch. The second transistor switch and the third transistor switch arranged in back to back configuration such that i) the second transistor switch is configured to interrupt current flowing in a first direction from the first terminal to the second terminal and ii) the third transistor is configured to interrupt current flowing in a second direction from the second terminal to the first side terminal. The DC solid state circuit breaker also includes a controller configured to detect a fault condition and control operation of the power electronics section and the one or more airgap sections in response to detecting the fault condition.

A fault protection system for a power system of a dynamically positioned vessel is provided. The power system is separated into two or more power system sections, each including a bus section of a power distribution bus. The bus sections are connected by bus ties in a ring configuration. Each bus section includes a connection to a generator and a connection to a thruster drive of the dynamically positioned vessel. The fault protection system includes a fault isolation system which includes for each power system section a bus tie circuit breaker for breaking the connection provided by the bus tie.

A network protector includes: a first resettable switching apparatus configured to control an electrical connection between a distribution transformer and a first electrical feeder of a secondary electrical distribution network; a first communications interface; and a first controller configured to: determine a direction of power flow in the first electrical feeder; cause the first communications interface to provide a first indication of the direction of power flow in the first electrical feeder to a second network protector; and receive a second indication from the second network protector. The second indication includes an indication of the direction of power flow in a second electrical feeder of the secondary electrical distribution network.