Abstract: Methods for detecting network model data errors are disclosed. In some examples, methods for detecting network model data errors may include splitting a network model into a first plurality of portions, executing an algorithm on each of the portions, identifying a portion for which the algorithm is determined to be non-converged, splitting the identified portion into a second plurality of portions, repeating the executing, identifying and splitting the identified portion until a resulting identified portion is smaller than a predefined threshold, and examining the resulting identified portion to identify plausible data errors therein. In some examples, examining the resulting identified portion to identify plausible data errors therein may include executing a modified algorithm, which may include an augmented measurement set, on the identified portion.

Abstract: Techniques are disclosed for performing the estimation and/or prediction of the dynamic system state of large power system networks, using a multi-processor approach. More particularly, a large power system network is divided into smaller sub-systems, each sub-system having associated dynamic state variables. Each sub-system is assigned to one or more of a plurality of processing elements, and dynamic state variables for each sub-system are estimated or predicted independently, using the processing elements and sensor measurements. In several embodiments, the dynamic state of each sub-system is computed through the construction of a set of dedicated observers, such as linear parameter-varying (LPV) observers, which are designed to reduce the effects of other sub-systems on the state estimation problem.

Abstract: The method of determining back-feed paths is capable of efficiently solving multi-layer restoration problems by minimizing a fitness function using an iterative genetic algorithm. The method optimizes back-feeding of out-of-service areas by minimizing power loss, switching, unserved loads and voltage/current violations. The efficiency of the algorithm is further increased through the use of a reactive Tabu search to prevent duplicate candidate systems.

Abstract: A power system grid is decomposed into several parts and decomposed state estimation steps are executed separately, using Lagrangian relaxation and blockwise Gauss-Seidel solution. The achieved solution is the same that would be achieved with a simultaneous state estimation approach. With the disclosed approach, the state estimation problem can be distributed among decomposed estimation operations for each subsystem, where the decomposed estimation operations coordinate with one another to yield the complete state estimate. The approach is particularly suited for estimating the state of power systems that are naturally decomposed into separate subsystems, such as separate AC and HVDC systems, and/or separate transmission and distribution systems.

Abstract: Techniques are disclosed for performing the estimation and/or prediction of the dynamic system state of large power system networks, using a multi-processor approach. More particularly, a large power system network is divided into smaller sub-systems, each sub-system having associated dynamic state variables. Each sub-system is assigned to one or more of a plurality of processing elements, and dynamic state variables for each sub-system are estimated or predicted independently, using the processing elements and sensor measurements. In several embodiments, the dynamic state of each sub-system is computed through the construction of a set of dedicated observers, such as linear parameter-varying (LPV) observers, which are designed to reduce the effects of other sub-systems on the state estimation problem.

Abstract: Methods for detecting network model data errors are disclosed. In some examples, methods for detecting network model data errors may include splitting a network model into a first plurality of portions, executing an algorithm on each of the portions, identifying a portion for which the algorithm is determined to be non-converged, splitting the identified portion into a second plurality of portions, repeating the executing, identifying and splitting the identified portion until a resulting identified portion is smaller than a predefined threshold, and examining the resulting identified portion to identify plausible data errors therein. In some examples, examining the resulting identified portion to identify plausible data errors therein may include executing a modified algorithm, which may include an augmented measurement set, on the identified portion.

Abstract: A method and a protective device operable to perform the method are provided, wherein the method is for detecting and analyzing faults in a first cable and one or more other cables, which convey power in a three phase feeder system. Current magnitude in the first cable is compared to a threshold level. If the current magnitude exceeds the threshold level, the duration of the condition is measured. If the duration falls within a predetermined duration range, a predetermined time interval is allowed to pass and then a determination is made whether a fault is detected in the one or more other cables. If a fault is not detected in the one or more other cables, then a determination is made that a single phase fault has occurred in the feeder system.

Abstract: The method of determining back-feed paths is capable of efficiently solving multi-layer restoration problems by minimizing a fitness function using an iterative genetic algorithm. The method optimizes back-feeding of out-of-service areas by minimizing power loss, switching, unserved loads and voltage/current violations. The efficiency of the algorithm is further increased through the use of a reactive Tabu search to prevent duplicate candidate systems.

Abstract: A method of forecasting loads on a distribution network is disclosed. The method employs load profiles in combination with short-term load estimations to forecast expected loads on a distribution network. The predicted loads may then be used by power restoration controllers when performing back-feed capacity checks.

Abstract: A method and a protective device operable to perform the method are provided, wherein the method is for detecting and analyzing faults in a first cable and one or more other cables, which convey power in a three phase feeder system. Current magnitude in the first cable is compared to a threshold level. If the current magnitude exceeds the threshold level, the duration of the condition is measured. If the duration falls within a predetermined duration range, a predetermined time interval is allowed to pass and then a determination is made whether a fault is detected in the one or more other cables. If a fault is not detected in the one or more other cables, then a determination is made that a single phase fault has occurred in the feeder system.