Hitachi, Ltd.

Shota Omi

Masatoshi Kumagai

Kenichiro Yamane

Masahiro Watanabe

Yuki Tsujii

Yasuo Sato

Yasushi Tomita

Masahiro Yatsu

Eisuke Kuroda

Nao Saito

Yasushi Harada

Taichiro Kawahara

Kouichi Hara

Yukihiro Takatani

Kenichirou Yamane

A regulated power procurement segment determination unit refers to a renewable energy theoretical maximum value database and a renewable energy output database and determines segments for procurement of regulated power, a demand/supply control simulation unit refers to the renewable energy output database, a demand database, and a power generator database, performs demand/supply control simulation by using the segments for procurement of regulated power, renewable energy output data, demand data, and power generator data, and predicts, on the basis of the demand/supply control simulation results, frequency changes and procurement costs regarding the segments for procurement of regulation power, and a segment selection unit refers to a cost database and a frequency change database and selects a segment for procurement of regulation power on the basis of the frequency changes and the procurement costs regarding the segments on which prediction has been performed.

Adjustment power procurement device and adjustment power procuring method

In order to suppress frequency fluctuation caused by a load frequency, an AR calculating section calculates an AR using system frequency deviation and tie-line power flow deviation as inputs. An output distribution ratio determining section determines a ratio of output distribution according to merit order based on the AR calculated by the AR calculating section. An output distributing section determines output distribution according to an output change speed based on the output distribution ratio determined by the output distribution ratio determining section according to the output change speed. An output distributing section determines output distribution according to the merit order based on the output distribution ratio determined by the output distribution ratio determining section according to the merit order. An output distribution instruction value determining section determines an output distribution instruction value to each regulated power source using, as inputs, output distribution values determined by the output distributing sections.

Load frequency control device and load frequency control method

There is provided an electric power system monitoring apparatus that can estimate dynamic behavior constants using measurement signals and can obtain the accuracy of an estimation result. An apparatus according to the present invention that monitors an electric power system includes a dynamic behavior constant estimation unit to estimate a predetermined dynamic behavior constant from a measurement value obtained from the electric power system, a relative accuracy calculation unit to calculate, from the measurement value, a relative accuracy index that indicates accuracy of a dynamic behavior constant estimation value estimated at the dynamic behavior constant estimation unit, and an estimation error calculation unit to calculate an estimation error from reference dynamic behavior information, the dynamic behavior constant estimation value, and the relative accuracy index. Thus, after the accuracy of a dynamic behavior constant estimation value is grasped, a process using the estimation value can be executed.

Electric power system monitoring apparatus and electric power system monitoring method

It is possible by means of a system simulation device to extract a disturbance mode wherein multiple accident conditions are assumed and to determine control parameters, but when the number of accident conditions increases, a threshold value pertaining to a divergence constant deviates prior to an update period, with the result that an uncontrollable disturbance mode appears. In order to solve this problem, the present invention is a power system stabilization system for determining control parameters for a control device connected to a power system, the power system stabilization system equipped with: a disturbance mode prediction unit for predicting a disturbance mode of a power system on the basis of operation information and an assumed system configuration for the power system; a post-control parameter update period prediction unit for predicting an update period for a post-control parameter in post-control after a disturbance has occurred; a threshold value setting unit for setting a threshold value pertaining to a divergence constant on the basis of the disturbance mode and the update period for the post-control parameter; and a control parameter determination unit for determining a control parameter of the control device on the basis of the disturbance mode and the threshold value.

Power system stabilization system and method

The setting range of the voltage and the reactive power of a power system is maintained during variations of voltage and power flow due to the output variation of renewable energy of a large number of power supplies which fluctuate due to weather. A voltage/reactive power operation assisting device is provided with a first database for storing the data to be evaluated, target value data, individual control device control method data, and individual control device data of an individual control device for adjusting the voltage/reactive power of a power system. A second database stores the device operation data of the individual control device; and the operation of the individual control device is predicted from the data stored in the first database to obtain individual control device operation prediction data. A display unit displays the individual control device operation prediction data and the device operation data in a contrastive manner.

Voltage/reactive power operation assisting device and assisting method, and voltage/reactive power operation monitoring control device and monitoring control method

A system stabilization system () is provided with: at least one of a power flow state database (DB) and a system configuration database (DB); a device state database (DB) in which the device states of a stabilizing device are recorded; a stabilizing effect index calculation function () for indexing the stabilizing effect of the stabilizing device on the basis of a device state and one or both of a power flow state and a system configuration; and a display means for displaying or outputting a stabilizing effect index obtained by the stabilizing effect index calculation function, in contrast with contrasted elements included in the device state, the power flow state, and the system configuration.

Power system stabilization system

A power system control instruction device performing a control instruction to the control device that controls the power system on the basis of a measured value transmitted from a sensor measuring a state value of the power system and a method for performing such a control instruction are provided. The device obtains a centralized control amount using a measured value of the sensor such that a system voltage meets a predetermined control purpose, and creates a distributed control model using the measured value and the centralized control amount. The device then determines whether or not a voltage deviation from the voltage appropriate range occurs when the control device performs control on the basis of the distributed control model, and re-creates the distributed control model when the voltage deviation occurs, and transmits the distributed control model that is re-created to the control device.

Power system control instruction device and method for controlling a voltage of a power system

A distributed controller collects measurement value data of a voltage and a current in an own node and in another node; using the measurement voltage and the current of the own node and the measurement voltage and current of another node as input data, estimates a voltage or a current as a state quantity of the electric power system regarding another node from which the measurement value data cannot be collected, and outputs the estimate values; using the measurement data, the estimate value outputted from the state estimation functional unit and a voltage target value that has been set for each node, outputs the control commands for voltage controllers based on voltage change amounts to be distributed to the voltage control devices of the nodes including the own node. The voltages in the electric power system are controlled by superposition of voltage change amounts by the voltage control devices.

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Tokyo, Japan

Shota Omi