1305results about "Contigency dealing ac circuit arrangements" patented technology

A variable speed wind turbine employing a rotor connected to a multiplicity of synchronous generators with wound field or permanent magnet rotors. A passive rectifier and an inverter are used for power transfer back to the grid. A Turbine Control Unit (TCU) commands a required generator torque based on rotor speed and power output of the turbine inverters. Torque is controlled by regulating the DC current by control of the inverter. A main-shaft-damping filter is provided by measurement of the DC bus voltage. In high winds the turbine remains at a constant average output power through a constant torque command and a varying pitch command to a rotor pitch servo system. A set point is fixed at the inverter output such that output VAR load is minimized running the turbine at very nearly unity power factor. Dynamic VAR and power factor control is provided by a separate VAR apparatus.

A variable speed wind turbine employing a rotor connected to a multiplicity of synchronous generators with wound field or permanent magnet rotors. A passive rectifier and an inverter are used for power transfer back to the grid. A Turbine Control Unit (TCU) commands a required generator torque based on rotor speed and power output of the turbine inverters. Torque is controlled by regulating the DC current by control of the inverter. A main-shaft-damping filter is provided by measurement of the DC bus voltage. In high winds the turbine remains at a constant average output power through a constant torque command and a varying pitch command to a rotor pitch servo system. A set point is fixed at the inverter output such that output VAR load is minimized running the turbine at very nearly unity power factor. Dynamic VAR and power factor control is provided by a separate VAR apparatus.

A method and system for monitoring and controlling a power distribution system is provided. The system includes a plurality of circuit breakers and a plurality of node electronic units. Each node electronic unit is mounted remotely from an associated circuit breaker that is electrically coupled with one of the node electronic units. The system also includes a first digital network, and a first central control unit. The first central control unit and the plurality of node electronic units are communicatively coupled to the first digital network. The method includes receiving digital signals from each node electronic unit at the central control unit, determining an operational state of the power distribution system from the digital signal, and transmitting digital signals to the plurality of node electronic units such that the circuit breakers are operable from the first central control unit.

Systems and methods for managing power on an electric power grid including a server for communicating IP-based messages over a network with distributed power consuming devices and / or power supplying devices, the IP-based messages including information relating to activities by the power consuming devices and / or the power supplying devices; and wherein the information is transformed by the system into settlement grade data corresponding to the activities of the power consuming devices and / or the power supplying devices.

A wind powered turbine with low voltage ride-through capability. An inverter is connected to the output of a turbine generator. The generator output is conditioned by the inverter resulting in an output voltage and current at a frequency and phase angle appropriate for transmission to a three-phase utility grid. A frequency and phase angle sensor is connected to the utility grid operative during a fault on the grid. A control system is connected to the sensor and to the inverter. The control system output is a current command signal enabling the inverter to put out a current waveform, which is of the same phase and frequency as detected by the sensor. The control system synthesizes current waveform templates for all three-phases based on a sensed voltage on one phase and transmits currents to all three-phases of the electrical system based on the synthesized current waveforms.

Systems and methods for distributed control and energy management of one or more communities of energy-consuming units may include aggregation of consumption data from units, and determining per-unit electricity consumption based thereon, including consumption of backup power provided by a community during periods of time of poor quality (brownouts) or blackouts of a utility. A system may calculate and assess to respective units per-unit costs for such backup power. A system may also issue a command or alert to units to carry out one or both of community electricity usage objectives and electricity quotas required by the utility, which may be determined through execution of rules.

A method of monitoring and controlling a power distribution system is provided. The power distribution system includes a plurality of circuit breakers, a plurality of node electronic units, and wherein each associated circuit breaker is electrically coupled with each respective node electronic unit. The system also includes at least one digital network, and at least one central control processing unit (CCPU) wherein each CCPU includes a first power system global information set, and each CCPU is communicatively coupled to the plurality of node electronic units. The method includes transmitting at least one digital message from each node electronic unit to each CCPU over a respective network, determining an operational state of the power distribution system from the digital message, and transmitting at least one multicast message from each CCPU to each node electronic unit such that the circuit breakers are operable from each CCPU.

According to an aspect of the invention a method is provided comprising: providing a model for a predetermined location within an electrical power system having therein distributed resources (DR), the model based on known system conditions, the model indicative of first sensed characteristics of the electrical power system at the predetermined location; sensing at the predetermined location characteristics of the electrical power system corresponding to at least some of the first sensed characteristics; determining a status of the electrical power system network indicative of an islanding event in dependence upon sensing and other than in dependence upon other sensed data sensed remotely from the predetermined location; and, controlling a distributed resource in dependence upon the status

A methodology and related system apparatus is provided for using and coordinating the use of information conveyed over communications to most efficiently and flexibly respond to abnormalities to reconfigure and restore service to end customers in commodity distribution systems in a manner to enhance the reconfigurability of the distribution system, e.g. circuit reconfiguration in an electrical power distribution system. Methodology is also provided to appropriately allocate system resources of the distribution system when so desired, e.g. to prevent the potential overloading of electrical power sources. In one illustrative arrangement, the methodology is characterized by resources at each node and communications of source allocation data or messages to other nodes to request and establish an appropriate allocation of system resources. In a preferred arrangement and especially useful for larger distribution systems, “teams” of nodes are defined in the distribution system having associated switching controls with the various teams communicating amongst each other to “negotiate” or work out the most efficient and expeditious reconfiguration of the system in response to fault conditions and other circuit abnormalities.

A methodology and related system apparatus is provided for using and coordinating the use of information conveyed over communications to most efficiently and flexibly respond to abnormalities to reconfigure and restore service to end customers in commodity distribution systems in a manner to enhance the reconfigurability of the distribution system, e.g. circuit reconfiguration in an electrical power distribution system. Methodology is also provided to appropriately allocate system resources of the distribution system when so desired, e.g. to prevent the potential overloading of electrical power sources. In one illustrative arrangement, the methodology is characterized by resources at each node and communications of source allocation data or messages to other nodes to request and establish an appropriate allocation of system resources. In a preferred arrangement and especially useful for larger distribution systems, “teams” of nodes are defined in the distribution system having associated switching controls with the various teams communicating amongst each other to “negotiate” or work out the most efficient and expeditious reconfiguration of the system in response to fault conditions and other circuit abnormalities.

A method and system for monitoring and controlling a power distribution system is provided. The system includes a plurality of circuit breakers and a plurality of node electronic units. Each node electronic unit is mounted remotely from an associated circuit breaker that is electrically coupled with one of the node electronic units. The system also includes a first digital network, and a first central control unit. The first central control unit and the plurality of node electronic units are communicatively coupled to the first digital network. The method includes receiving digital signals from each node electronic unit at the central control unit, determining an operational state of the power distribution system from the digital signal, and transmitting digital signals to the plurality of node electronic units such that the circuit breakers are operable from the first central control unit.

Techniques for determining conditions of power lines in a power distribution system based on data collected by a plurality of sensor units deployed in the power distribution system. The techniques include obtaining data associated with measurements collected by at least two sensor units in the plurality of sensor units, and determining, by using at least one processor, at least one condition of at least one power line in the power distribution system by using the data obtained by the at least two sensor units.

A wind powered turbine with low voltage ride-through capability. An inverter is connected to the output of a turbine generator. The generator output is conditioned by the inverter resulting in an output voltage and current at a frequency and phase angle appropriate for transmission to a three-phase utility grid. A frequency and phase angle sensor is connected to the utility grid operative during a fault on the grid. A control system is connected to the sensor and to the inverter. The control system output is a current command signal enabling the inverter to put out a current waveform, which is of the same phase and frequency as detected by the sensor. The control system synthesizes current waveform templates for all three-phases based on a sensed voltage on one phase and transmits currents to all three-phases of the electrical system based on the synthesized current waveforms.

A process of implementing, or engineering, topology-dependent functions based on a formal description of the Substation Automation system, includes performing a topology analysis of the current single line state. A topology interpreting implementation replacing complex topology analysis logics can include the project specific static single line topology and the connection to the real process state data. All information can be delivered in an IEC 61850 conforming SCD file. The interface description for controlling and monitoring the load transfer application can be generated automatically from the SCD file.

A data sample and transmission module for a power distribution system is provided. The module has a microprocessor and a network interface. The microprocessor samples first signals indicative of a condition of power in the power distribution system. The network interface places the microprocessor in communication with a data network. The microprocessor samples the first signals based in part upon a synchronization signal transmitted on the data network.

Controlling a wind power plant comprising at least one wind turbine generator for producing power to an electrical grid where the amount of said power is based on a signal response in a voltage signal in said electrical grid due to a change in power output into said electrical grid.

Techniques for determining conditions of power lines in a power distribution system based on measurements collected by a plurality of sensor units deployed in the power distribution system. Techniques include obtaining first transformed data associated with a first set of one or more measurements collected by a first sensor unit in the plurality of sensor units and second transformed data associated with a second set of one or more measurements collected by a second sensor unit in the plurality of sensor units, and determining, by using at least one processor and based at least in part on one or more features calculated from the first transformed data and the second transformed data, at least one condition of at least one power line in the power distribution system.

Techniques comprising obtaining, using a sensor unit coupled to a power line in a power distribution system, at least one measurement of at least one inertial property of the power line; and detecting at least one condition of the power line at least in part by analyzing the at least one measurement. A sensor unit configured to be coupled to a power line in a power distribution system, the sensor unit comprising an inertial sensor configured to collect at least one measurement of at least one inertial property of the power line.

There is disclosed a protection system for a power distribution system having a plurality of breakers arranged in a hierarchy. The protection system has a network and a breaker coupled to the power distribution system. A module is coupled to the network and the breaker is at a first level in the hierarchy. The module samples an electrical condition of the power distribution system at the breaker and monitors the electrical condition for a predetermined trip condition. The module, upon detection of the predetermined trip condition, trips said breaker if the first level is a lowest level of the hierarchy, but monitors the network for a notification message if the first level is not the lowest level of the hierarchy.

A microgrid system may control power distribution among a plurality of interconnected microgrids operated under droop mode. The microgrids may operate both autonomously and as part of the system. Stable power distribution between the microgrids may be performed by monitoring operation of the microgrids and electrically disconnecting the microgrids from one another when a power outage or performance outside of a tolerance is detected. Network lines between the microgrids may remain in communication while the microgrids are disconnected from one another. The microgrids may operate autonomously under a preset operating droop frequency until power stability is detected at a boundary between adjacent microgrids. The microgrids may communicate with one another adjusting operating droop until synchronization among microgrids is achieved and the microgrids can be reconnected into the microgrid system.

A power converter circuit and associated triggering method for connecting a three-phase generator to an electrical network. The circuit includes a first direct connection of the generator to the network and a second connection of the generator to the network, through a four-quadrant converter which includes a first power converter, whose alternating voltage terminals are connected to the generator, and a second power converter, whose alternating voltage terminals are connected to the network. The triggering method for power compensation in the event of a short circuit is such that in a first period of time after the short, the second power converter outputs reactive power into the network; in a second period of time, the power converter feeds reactive power back into the network; and in a third period of time, the entire four-quadrant converter controls the gentle restarting, without loading the network with reactive power from the generator.

A system for accurately determining real-time Available Transfer Capability and the required ancillary service of large-scale interconnected power systems in an open-access transmission environment, subject to static and dynamic security constraints of a list of credible contingencies, including line thermal limits, bus voltage limits, voltage stability (steady-state stability) constraints, and transient stability constraints.

Systems, methods, and apparatus for evaluating load power consumption utilizing a power meter are provided. A power line signal for a structure associated with a power meter may be measured by the power meter. The power line signal may be decomposed by the power meter into respective power consumption data for a plurality of individual loads powered by the power line signal. The power consumption data for a load included in the plurality of individual loads may be compared by the power meter to expected power consumption data for the load. Based at least in part upon the comparison, the power meter may determine whether the load is operating within one or more desired parameters.

The invention discloses a permanent magnetic direct-drive type offshore wind power plant grid-connected system topology structure and a control method thereof. A grid-connected system comprises a DC bus current collection type wind power plant, a wind field network-side converter station, a dual-stage boost transformer, an offshore rectification station, a seabed DC cable, a shore inversion station, a grid-connected side boost transformer and a land power grid which are successively connected, wherein the DC bus current collection type wind power plant employs a DC bus current collection topology structure and comprises multiple groups of wind turbines which are successively connected, a permanent magnetic synchronous generator, a machine-side rectifier and a DC bus for current collection. The control method is that the machine-side rectifier employs dual-closed-loop control of a rotating speed outer loop and a current inner loop, the wind field network-side converter station employs dual-closed-loop control of a voltage outer loop and the current inner loop, the offshore rectification station employs control of fixed AC voltages and fixed frequencies, and the shore inversion station employs dual-closed-loop control of fixed DC voltages and fixed reactive power. According to the invention, multi-machine parallel-connected operation can be realized, the electric energy conversion efficiency is improved, and the grid-connected AC harmonic quantity is reduced.

There is disclosed a protection system for a power distribution system having a plurality of breakers arranged in a hierarchy. The protection system has a network and a breaker coupled to the power distribution system. A module is coupled to the network and the breaker is at a first level in the hierarchy. The module samples an electrical condition of the power distribution system at the breaker and monitors the electrical condition for a predetermined trip condition. The module, upon detection of the predetermined trip condition, trips said breaker if the first level is a lowest level of the hierarchy, but monitors the network for a notification message if the first level is not the lowest level of the hierarchy.

The present invention discloses a data-driven three-stage scheduling method for electricity, heat and gas networks based on wind electricity indeterminacy, including the following steps: S1, initializing; S2, establishing a deterministic electricity-heat-gas coordination optimized scheduling model; S3, establishing a data-driven distributed robust scheduling optimization model under mixed norms; S4, solving a master economic scheduling problem; S5, verifying convergence of a wind electricity indeterminacy subproblem: if the subproblem converges, going to step S6, otherwise going to step S4 and adding a constraint to the master economic scheduling problem by using a CCG algorithm; and S6, checking the convergence of a gas network operation constraint subproblem: if the gas network operation constraint subproblem converges, ending the calculation to obtain an optimal solution, otherwise, going to step S4 and adding a Benders cut set constraint to the master economic scheduling problem.

The present invention provides an analysis method for an electrical power system whereby the plurality of buses are grouped into agents, family lines of agents and families of agents based on the reactive reserves depleted when the buses are loaded. Contingencies are then applied to the electrical power system and the reactive reserves are monitored and an exhaustion factor is determined for one or more family lines in one or more families. A method for selecting double outage that have no solution for each outage that has no solution when the outage is removed in small steps and an additional step has no solution. The boundary case solution is used to assess where, why, and how the contingency causes voltage instability, voltage collapse, and local blackout. Based on this information, the design of voltage rescheduling, active rescheduling, unit commitment, load shedding is determined that can be used as preventive, corrective, or emergency controls in applications such as system design and planning, operation planning, reactive and voltage management, real time control, and Special Protection System Control. Based on this information, solutions can then be applied to the political power system.

A method of performing energy calculations in a power distribution system is provided. The method includes sampling a first voltage at a first module in the power distribution system; communicating the first voltage from the first module to a central controller; performing an energy calculation in the central controller based at least in part on the first voltage; and applying the energy calculation to a second module in the power distribution system. In some embodiments, the energy calculation is also based upon a second current from the second module.

There is provided a method of operating a wind power installation. Under first operating conditions in a normal operating mode the wind power installation delivers a first power to a connected electrical network. That first power is proportional to the wind speed. The wind power installation is controlled in such a way that upon the occurrence of a disturbance it remains on the connected electrical network and delivers to the connected electrical network a second power which is lower than the first power. Upon cessation of the disturbance and under the first operating conditions a third power is briefly delivered to the connected electrical network, the third power being significantly higher than the first power.

A method for power distribution network correlation and analysis includes receiving event data from a plurality of data sources, identifying an event of interest, retrieving, in a querying engine, the event data, correlating the event data and the event of interest and identifying one or more root causes of the event of interest.