Embodiments of this present disclosure may include a system with a first power converter and a control system. The first power converter may supply a first output power to a first backplane at least sometimes concurrent to a second power converter supplying a second output power to a second backplane. The control system may be electrically coupled to the first backplane and the second backplane. The control system may balance a first electrical property and a second electrical property provided to each of one or more load components electrically coupled to the first backplane and the second backplane.

Distance protection for electric power delivery systems that include an unconventional source is disclosed herein using apparent impedance independent of memory and cross-phase polarizing. The apparent impedance may be compared with an offset distance operating characteristic. Fault direction is determined by using zero-sequence ground directional logic for phase-to-ground faults. For phase-to-phase faults, fault direction is determined using weak-infeed directional logic. Fault direction may further use incremental quantity directional principles. The distance protection may further determine a faulted loop using voltage logic. The distance protection may select between traditional distance protection and the methods described herein based on the current feeding the fault.

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.

Distance protection for electric power delivery systems that include an unconventional source is disclosed herein using apparent impedance independent of memory and cross-phase polarizing. The apparent impedance may be compared with an offset distance operating characteristic. Fault direction is determined by using zero-sequence ground directional logic for phase-to-ground faults. For phase-to-phase faults, fault direction is determined using weak-infeed directional logic. Fault direction may further use incremental quantity directional principles. The distance protection may further determine a faulted loop using voltage logic. The distance protection may select between traditional distance protection and the methods described herein based on the current feeding the fault.

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.

A method for locating phase faults in a microgrid in off-grid mode. The method includes obtaining a grid topology of the microgrid having at least two busbars and determining the position of all circuit breaker position of the grid topology. Further, acquiring measurement data which includes current magnitude and voltage magnitude. Monitoring the at least two busbars for a voltage dip in one of phase-to-phase or phase-to-neutral voltages. On detecting a voltage dip, determining a defect phase having a minimum phase-to-neutral voltage value. And for the defect phase performing busbar analysis and feeder analysis, using phase-directional information.

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 DC voltage switch includes a semiconductor-based electronically controllable switching device, a sensor provided upstream of the switching device for determining the DC voltage bus-side voltage level, a sensor provided downstream of the switching device for determining the DC voltage branch-side voltage level, a current sensor for determining current level and direction, a control device designed such that the direction and level of the current are determined, the flow of current is interrupted by the switching device when a first threshold value of the current level is exceeded, and when the first threshold value of the current level is exceeded in the reverse direction: the DC voltage bus-side voltage level is compared with the DC voltage branch-side voltage level, and the switching device is switched on upon a voltage difference being less than a voltage difference value.

Systems and methods may be used to determine fault types and/or directions even during a loss of potential by receiving, at one or more processors, an indication of a pre-fault power flow direction for a power delivery system. The one or more processors then determine a fault direction during a fault for the power delivery system using current vector angles and the pre-fault power flow direction.

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.