General Electric Company

Reigh Allen Walling

Nicholas Wright Miller

Einar Vaughn Larsen

Robert William Delmerico

Wei Ren

Kara Clark

Zhihong Ye

Mark Edward Cardinal

Ara Panosyan

Amol Rajaram Kolwalkar

John Keith Nelson

Swakshar Ray

Pengwei Du

Michael Lewis Reichard

William James Premerlani

Luis Jose Garces

Lei Li

Rui Zhou

James Patrick Lyons

Changyong Wang

Rayette Ann Fisher

Jason Wayne Black

Sumit Bose

Johannes Huber

Yan Pan

William Jerome Burke

Yan Liu

Mark Dame

Andre Langel

Daniel Kotzor

Peter Claudius Sanza

Harjeet Johal

Thomas Alexander Wilkins

Vinod John

Felipe Antonio Chegury Viana

Krishna Kumar Anaparthi

Murali Mohan Baggu Datta Venkata Satya

Nagwa M Elkachouty

Pan Yan

Devon Leigh Manz

A method and system for use in controlling an electric network are provided. The system includes an Integrated Volt-VAr Control (IVVC) component configured to determine optimization parameters for slow dynamics electromechanical devices and fast dynamics DER devices coupled to the network. The slow dynamics devices are controlled by a present state of the electric network and a voltage rise table that is adaptively updated in real-time using a command output, or a power flow-based complete optimization routine that generates optimal setpoints for the traditional controllable assets and for at least some of the fast dynamics DER devices. The fast dynamics devices are controlled locally using a control algorithm that uses a reactive power contribution based on IVVC settings, based on photo-voltaic (PV) plant active power variations, based on power factor, or based on a voltage of the local electric network.

Methods and systems for integrated Volt/VAr control in electric network

A reactive power control system is provided. The reactive power control system computes a required value for a reactive power based on a state observer method for at least one electrical element in an electrical system. The reactive power control system also generates a reactive power command based on the required value of the reactive power. The reactive power control system further transmits the reactive power command to the electrical element in the electrical system for generating the required value of reactive power to compensate for a voltage change induced by the respective electrical element in the electrical system.

System and method for reactive power compensation

A reactive power compensation method includes generating a variable power factor curve for at least one power generator based on information regarding network parameters; obtaining a value of an active output power parameter from the at least one generator; computing a reactive power based on the variable power factor curve and the value of the active power output parameter of the at least one generator; generating a reactive power compensation command based on the computed reactive power; and transmitting the reactive power compensation command to the at least one power generator for controlling operation of the at least one power generator.

System and method for reactive power compensation in power networks

A system for distributing electrical current to a plurality of loads includes a first sensor coupled to an input of a protection zone for measuring a first current entering the protection zone, wherein the protection zone includes at least a portion of an electrical distribution feeder. The system also includes a second sensor coupled to an output of the protection zone for measuring a second current exiting the protection zone, and a processor coupled to the first sensor and to the second sensor. The processor is programmed to receive measurements representative of the first current and the second current, and calculate a reactive current differential of the protection zone based on the first current and the second current. The processor is also programmed to compare the reactive current differential with a fault threshold, and generate an error notification if the reactive current differential is greater than the fault threshold.

Electric distribution system protection

An electric distribution system includes at least one feeder and a protection and control system. The feeder includes at least one segment including a first end and an opposing second end. The protection and control system includes a protective device and an electric current measuring device coupled to the segment proximate each end. The system further includes at least one processor coupled in communication with the electric current measuring devices. The at least one processor is programmed to determine a difference between a synchronized first electric current measured proximate the first end and a synchronized second electric current measured proximate the opposing second end and determine a switching condition of the protective devices as a function of the difference between the synchronized first and second electric currents.

System for electric distribution system protection and control and method of assembling the same

A system and method for simultaneously restoring power to loads in a distribution network that experienced an outage. The pickup load on the feeder in the distribution network is estimated and the load limit on the feeder is determined. The load on the feeder is divided into groups based on the load limit. A restoration load control process is determined, and power is restored to each of the groups simultaneously based on the power restoration control process.

System and method for managing cold load pickup using demand response

A method of assembling a motor stall correction system includes coupling an inverter-based electric power generation device to an electric power inverter assembly. The method also includes coupling the electric power inverter assembly to at least one induction motor. The method further includes operatively coupling at least one controller to the electric power inverter assembly. The controller is programmed to transmit electric current from the inverter-based electric power generation device to the electric power inverter assembly. The controller is also programmed to transmit real current and reactive current from the electric power inverter assembly to the induction motor. The controller is further programmed to modulate the real current and the reactive current as a function of at least one of an electric power grid frequency and an electric power grid voltage.

Method and apparatus for control of fault-induced delayed voltage recovery (FIDVR) with photovoltaic and other inverter-based devices

A voltage control arrangement for a system of multiple windfarms with transmission lines. Voltage is regulated at a point of regulation on the system, such as a high voltage substation or other system bus. Regulation is achieved at the point of regulation by sensing the voltage, comparing to a reference voltage, and adjusting the reactive power output of the wind turbines and other equipment in the system. The regulation point may be shifted to another point if needed to respect voltage limits at that points of the system after attempting to shift reactive load to restore voltage within limits at the other points in the system. The reference voltage may be adjusted to minimize losses for the system of multiple windfarms and transmission lines. A loss optimizing algorithm is applied to the combined multiple windfarm and transmission line to shift reactive load among local windfarms to minimize losses and to shift reactive load among individual wind turbines within an individual windfarm.

Optimizing system loss for a system of multiple windfarms

Voltage control at windfarms

A windfarm system is provided that is optimized for minimizing electrical loss. The windfarm system includes a plurality of wind turbine generators and a collector system including a conductor or network of conductors. The collector system also including a plurality of transformers with one or more transformers connected between each wind turbine generator and the conductors, and a substation transformer connecting the windfarm collector system to the electrical grid. The windfarm system also includes a monitoring system for monitoring the windfarm system electrical output and thermal condition, and outputs of the individual wind turbine generators. A control function may include voltage and real and reactive power commands to the individual wind turbine generators. The control function incorporates an algorithm whose technical effect is minimizing electrical losses for the windfarm system.

Windfarm collector system loss optimization

A solar farm system is provided that is configured for reducing electrical loss. The solar farm system includes a plurality of PV arrays coupled to inverters and a collector system including a conductor or network of conductors. The collector system also includes a plurality of transformers with one or more transformers connected between the inverters and the conductors. The solar farm also includes a substation transformer connecting the solar farm collector system to the electrical grid. The solar farm includes a control system configured to determine at least one operating parameter for the solar farm system to reduce electrical loss and to regulate the collector system and the plurality of inverters based at least in part on the at least one operating parameter.

System and method for decreasing solar collector system losses

A method and system for reducing the cost of a combined offshore wind generation plant is provided by coupling the AC output of plural wind turbine generators to a single AC-DC converter prior to transmission of the DC power to an onshore DC-AC inverter site. The wind speed is monitored at selected locations within the wind plant, optionally, at selected turbine generators, and the operating frequency of the AC-DC converter is adjusted in accordance with a combine wind speed signal to permit operation of the plural wind turbines as a group. AC-DC followed by DC-AC conversions decouples the AC frequency produced by the wind turbines and allows the turbines to operate at variable frequency as a group.

Variable frequency wind plant

A wind turbine includes a rotor having a hub, at least one rotor blade coupled to the hub, and a rotor shaft coupled to said hub for rotation therewith. The wind turbine also includes an electrical generator coupled to the rotor shaft, and a generator-side frequency converter electrically coupled to the electrical generator for converting variable frequency AC received from the electrical generator into DC. The generator-side frequency converter is electrically coupled to an electrical load and is configured to at least one of supply reactive power to the electrical load and absorb reactive power from the electrical load. The wind turbine also includes a grid-side frequency converter electrically coupled to the generator-side frequency converter for converting DC received from the generator-side frequency converter into fixed frequency AC. The grid-side frequency converter is electrically coupled to the electrical load and is configured to at least one of supply reactive power to the electrical load or absorb reactive power from the electrical load.

Methods and apparatus for supplying and/or absorbing reactive power

A method for detecting islanding conditions in an electrical grid having a power line voltage includes monitoring a detectable signal different from the power line voltage at a generating station, superimposing the detectable signal onto the power line voltage at a grid point outside the generating station, and switching the generating station from a grid-connected mode of operation to an islanded mode of operation when the signal to which the detector is responsive is determined to be absent.

Detection of islanding in power grids

Growing community of inventors

Clifton Park, NY, United States of America

Reigh Allen Walling