Hitachi, Ltd.

Masahiro Yatsu

Eisuke Kuroda

Jun Yamazaki

Osamu Tomobe

Nao Saito

Sumito Tobe

Kenta Kirihara

Daichi Kato

Yasuo Sato

Toshiyuki Miyake

Taichiro Kawahara

Kouichi Hara

Akira Tsubota

Hiroo Horii

Masahiro Watanabe

Kenichiro Yamane

Toshiyuki Sawa

Shota Omi

Tatsuki Inuduka

Yutaka Kokai

Haruki Miyoshi

Shintaro Ueno

Taichirou Kawahara

This power system operation assisting device is provided with: a multiple signal frequency specifying unit that uses, as inputs, measured data of an object to be measured and a frequency specifying parameter for calculating a frequency component of the measured data to calculate an oscillation frequency; a generation source candidate calculation unit that uses, as an input, the calculated oscillation frequency to calculate a generation source candidate of an unstable oscillation occurring in a power system; a generation source guarantee test unit that calculates the guarantee test result of the generation source candidate; and a display unit that displays the oscillation frequency, the generation source candidate, and the guarantee test result.

Power system operation assisting device and method, and oscillation suppression system

To calculate the prediction of the power generation amount with high accuracy even when the amount of the track record data of the Generator power generation amount is insufficient or the amount of the weather track record data similar to the weather prediction result is small. A power generation amount prediction apparatus for predicting a power generation amount at a power plant that performs power generation by use of renewable energy, including: a model generation unit that generates a mathematical model of the power generation amount of the power plant in regard to each model generation time based on a weather track record and an output power track record in regard to the power plant; a similar track record data extraction unit that obtains a weather track record similar to weather prediction data and a corresponding output power track record as similar track record data; a model accuracy calculation unit that calculates accuracy of each of a plurality of mathematical models of the model generation unit in a weather condition similar to the weather prediction data; a model selection unit that selects a mathematical model to be used for the prediction by using the accuracy of each of the models; and a model output power prediction unit that predicts the power generation amount of the power plant by using the selected mathematical model.

Power generation amount prediction apparatus, power generation amount prediction method, system stabilization apparatus, and system stabilization method

An operation support device is provided with: a similarity determination unit for determining the similarity between actual measured data and simulated data, said actual measured data being measured in an operation target after performing control on the operation target on the basis of, among a plurality of control candidates managed using a control candidate table, a control candidate corresponding to an event having occurred in the operation target, said simulated data being obtained by a simulation assuming the system state of the operation target after performing control on the operation target on the basis of system data indicating the state of the operation target before performing the control on the operation target; and a control candidate table update unit for updating the control candidate table in accordance with the determination result of the similarity determination unit.

Operation support device and operation support method

A voltage stability monitoring device and a method capable of obtaining information of voltage stability that can be served to practical use within a range of assumed conditions during a predetermined monitoring period are provided. The present invention provides a voltage stability monitoring device for estimating a voltage stability by using a voltage stability curve representing the voltage stability in an electric power system, including a voltage stability limit prediction unit for predicting a voltage stability limit, a voltage stability calculation condition determination unit for determining voltage stability calculation conditions by using a prediction result of voltage stability limit, a voltage stability curve calculation unit for calculating the voltage stability curve using a result of the voltage stability calculation condition determination, and a voltage stability margin calculation unit for calculating a voltage stability margin using a calculation result of the voltage stability curve.

Voltage stability monitoring device and method

A power demand/supply adjustment power procurement plan support device supports a power system through a power transaction in the power market and has an added power transmission capacity analysis means and a target power transmittable capacity determination means. The added power transmission capacity analysis means obtains: actual power supply data including a power supply having supplied power to the power system and the actual value of a power supply amount; an actual power system stabilization data including a power supply performing power supply restriction for power system stabilization, an electric control amount or a customer facility performing a load restriction, and the actual value of a load control amount; and an actual power demand/supply adjustment power procurement data including a procurement amount of the power demand/supply adjustment power of a power supply participating in the power market and the actual value of the total procurement cost.

Power demand/supply adjustment power procurement plan support device and method, and power demand/supply adjustment power procurement plan support system

In a power system stabilization device and power system stabilization method, an excess/shortage of control is prevented and an appropriate control suitable for the system state is enabled. A power system stabilization device including a central processing unit in which there is determined, in advance, a device subject to control necessary to maintain stability when an assumed failure in a power system including renewable energy occurs, wherein the central processing unit executes, for each of a plurality of assumed failures, a computation for determining a subject of control necessary to maintain stability at the time of the assumed failure, and determines, in accordance with an output fluctuation scenario for renewable energy pertaining to the weather, the degree of priority of performing a computation for determining a subject of control necessary to maintain stability at the time of each of the assumed failures.

Power system stabilization device and power system stabilization method

A system operation support device in a power system stabilizes the power system and has a predicted accident time system state calculation unit that receives measured data, a system topology, and a target accident type as inputs, and calculates a system state and a predicted accident time system state. A control menu calculation unit receives the results of the predicted accident time system state as inputs and calculates a control menu. A restoration control means calculation unit receives the result of the control menu calculation as an input and calculates a restoration control procedure. A restoration prevention control procedure calculation unit receives the result of the restoration control and a target restoration time parameter as inputs and performs a power generator output adjustment time simulation, a necessary prevention control amount calculation, and a prevention control procedure calculation. A display unit displays the restoration control procedure and the prevention control procedure.

System operation support device and method in power system, and wide-area monitoring protection control system

A manipulation candidate classification unit provided in this operation assistance device classifies manipulation logs associated with a plurality of events stored in a past case database, as manipulation candidates, on the basis of measured value feature quantity tolerance ranges, and groups the classified manipulation candidates and the measured value feature quantity tolerance ranges together to create manipulation candidate groups. A manipulation candidate search unit searches a manipulation candidate database for a manipulation candidate group associated with a feature quantity that is associated with a past event and that is close to a feature quantity associated with a new event, and outputs the found manipulation candidate group to an output unit.

Operation assistance device and operation assistance method

A system operation decision-making assistance device includes: a state mode clustering unit that calculates, on the basis of measurement data DBof a power system and a clustering parameter DB, which state mode, from among prescribed state modes, applies to a power system; a state mode collation unit that collates state transition data DBindicating transitions between state modes and the calculated state mode to calculate state transition probability data, which is the probability of transitioning from the calculated state mode to each state mode defined in the state transition data; and an accident shift pattern calculation unit that calculates important accident cases on the basis of a system model DB, an importance parameter DBincluding the importance of a power system accident, the measurement data, and the calculated state transition probability data.

System operation decision-making assistance device and method

The voltage and reactive power monitoring/control method includes: measurement data for the power system and data for the system equipment of the power system are used to calculate the system status for the power system at the time of measurement; data for a status estimation calculation result and predicted data for the power generation and load of the power system are used to predictively calculate a system status at a future time from the time of the power system measurement; a fluctuation component is obtained for the predicted value of the data obtained from the power system; the reactive power required to suppress the fluctuation component is obtained, as a required reactive power amount; a reactive power distribution subject is selected from a plurality of pieces of control subject equipment; an output distribution calculation is performed for the required reactive power amount for the selected control subject equipment.

Voltage and reactive power monitoring/control device and method for calculating required reactive power amount for suppressing a fluctuation component and selecting an appropriate equipment

With conventional technology, since calculation of system stability is performed regarding all imaginable failure cases for the combinations of all objects to be controlled to determine an object to be controlled, there has been a problem of not being able to determine an object to be controlled in all the imaginable failure cases within a calculation period due to longer calculation time. In order to solve the problem, this apparatus for stabilizing a power system is provided with: an imaginable failure scenario generation unit; a power-flow state generation unit that generates a power-flow state of the power system; a system stability calculation unit that calculates system stability of the power system; a to-be-controlled candidate calculation unit that calculates a candidate object to be controlled for stabilization of the power system; a control table calculation unit that calculates a control table; a system stability calculation requiring/non-requiring state range extraction unit that extracts a state range where stability calculation of the power system is required and a state range where stability calculation is not required; and a system stability calculation requiring/non-requiring determination unit that determines whether or not stability calculation of the power system is required.

Apparatus and method for stabilizing power system

There is provided a voltage/reactive power control device, method, and a voltage/reactive power control system that allow a proper control even with a control delay or in a situation where the system conditions at the time of setting the voltage reference value may not be always reproduced. A voltage/reactive power control system is applied to a power system in which a monitoring point is set in a local system divided as appropriate from the power system and the local system includes a voltage/reactive power control device capable of adjusting voltage and reactive power at the monitoring point. The voltage/reactive power control system includes: a central control unit that sets a control target value of the voltage and reactive power at the monitoring point in the local system based on optimal power flow calculation using total system data on the power system, generates a correction function to correct the control target value in accordance with a change in state of the power system relating to the monitoring point by using past history information on the states of the power system, and outputs the control target value and at least one or more correction functions; a local control apparatus that, when the control target value is different from system data on the local system, uses the correction function to calculate a controlled variable for the voltage/reactive power control device necessary to attain the control target value; and a device control apparatus that controls the voltage/reactive power control device in accordance with the controlled variable from the local control apparatus.

Voltage/reactive power control apparatus, method, and voltage/reactive power control system

A system stability monitoring device monitors the stability of a power system and is equipped with: a storage unit for storing spot information indicating the positional relationship between a plurality of measurement spots in the power system; a receiving unit for receiving time-series measurement information measured by a measuring device provided at each of the measurement spots; and a calculation unit for detecting the frequency components of the power fluctuation from the measurement information, selecting, based on the frequency components, measurement spot group candidates that are measurement spots among the plurality of measurement spots, obtaining the electrical distances between the measurement spot group candidates on the basis of the spot information, and categorizing the measurement spot group candidates into at least one measurement spot group on the basis of the electrical distances.

System stability monitoring device and system stability monitoring system

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 voltage stability monitoring device, which monitors voltage stability of a power system, produces a plurality of assumed change scenarios indicating a scenario of a change that is assumed based on at least one of a system configuration of the power system and a change of a tide state, calculates the voltage stability using the assumed change scenario, calculates a voltage stability margin indicating margin degree of the voltage stability, based on the voltage stability selects an assumed change scenario with high severity of the voltage stability for each assumed change scenario, based on the voltage stability margin calculates which buses in the power system are vulnerable buses that decrease voltage stability, based on the assumed change scenario which is selected, and changes a monitoring target of the voltage stability, based on information of the vulnerable bus.

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Tokyo, Japan

Masahiro Yatsu