Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric Corporation

Nec Corporation

Daiichi Pharmaceutical Co., Ltd.

Masatoshi Takeda

Yoshiyuki Kono

Shinichi Ogusa

Akihiro Matsuda

Koji Temma

Satoshi Yasuda

Isao Kamiyama

Hitoshi Teramoto

Naohiro Toki

Hiroshi Yamamoto

Osamu Mori

Yuji Kuroda

Shinzo Tamai

Shuhei Fujiwara

Michihiro Tadokoro

Kazuyori Tahata

Nobuo Sashida

Fuminori Nakamura

Masao Yano

Shinji Tominaga

Tomohiko Aritsuka

Hiroshi Suzuki

Yoshiharu Tominaga

Kazuo Ikeda

Frederick Page

Junji Takeda

Tomohiko Tatsumi

Yoshitaka Tachibana

Setsuro Mine

Kenji Mori

Teito Suzuki

Ryo Hachiya

A power storage apparatus of one embodiment includes a storage bank including a plurality of power storage elements connected to each other; and one or plurality of first cells. The storage bank and the one or plurality of first cells are connected in series to each other. Each first cell includes a pair of input/output nodes, a bridge circuit including at least two semiconductor switching elements, and a power storage element connected to the pair of input/output nodes via the bridge circuit. A storage capacity of the power storage element of each first cell is smaller than a storage capacity of the storage bank.

Power storage apparatus and power system stabilization system

A photographing apparatus includes a camera; a light-emitting device provided in the vicinity of the camera; a human sensor that detects a photographic subject; first light emission control means for controlling light emission of the light-emitting device in accordance with a first mode when the photographic subject is detected; detection means for detecting that a photograph-taking timing has arrived when an interocular distance of the photographic subject in an image generated by the camera in accordance with the first mode becomes at least a prescribed distance; and second light emission control means for controlling light emission of the light-emitting device, at the photograph-taking timing, in accordance with a second mode in which a light emission intensity is higher than in the first mode.

Photographing apparatus, photographing method, and storage medium having program stored therein

A control device for an active filter connected in parallel with a load at an installation point with respect to an AC power supply provided in a power system includes a harmonic voltage detector to detect an m-order harmonic voltage (m is an integer not less than two) included in a voltage of the installation point, a phase corrector to correct a phase of the detected m-order harmonic voltage in accordance with whether an m-order harmonic impedance when an AC power supply side is seen from the installation point is capacitive or inductive, a command value generator to generate a first compensation command value for compensating for the m-order harmonic voltage included in the voltage of the installation point based on the m-order harmonic voltage after the correction, and an output controller to control an output of the active filter based on a first compensation command value.

Control device and active filter apparatus

In a reactive power compensation device, a control unit controls a magnitude of reactive power to be output by a reactive power output unit, based on a detected system voltage and one or more control parameters in a first operation mode. In a second operation mode, the control unit changes the magnitude of the reactive power to be output by the reactive power output unit to a power system in an output change period, calculates system impedances of the power system at a plurality of detection time points within the output change period, based on change amounts of the system voltage detected at the plurality of detection time points and corresponding change amounts of the reactive power, and, when a variation in the calculated system impedances is within an acceptable range, adjusts the one or more control parameters, based on the calculated system impedances.

Reactive power compensation device having function of detecting system impedance

Three-phase thyristor switched capacitors are delta-connected to three-phase AC buses. Each thyristor switched capacitor includes a reactor, a capacitor, and a thyristor switch that are electrically connected in series. The thyristor switches of the three phases are arranged so that the terminal-to-terminal distance between respective thyristor switches of respective phases are not uniform. The three-phase thyristor switched capacitors are configured so that the thyristor switched capacitors of two of the three phases having a shortest terminal-to-terminal distance therebetween are opposite to each other in terms of connection order in which the thyristor switch and the capacitor are electrically connected along a loop path made up of the delta-connected thyristor switched capacitors.

Static var compensator including series circuits of three phases that are delta-connected to three-phase AC buses

A first SVC is connected to a first bus. A first SVC control unit controls the first SVC. A first fluctuation-component-voltage generating unit includes a voltage reference circuit that outputs a voltage reference value. A second SVC is connected to a second bus. A second SVC control unit controls the second SVC. A second fluctuation-component-voltage generating unit includes a first-order-lag control block with limiter that generates a comparative voltage that follows a bus voltage of the second bus with a predetermined time lag characteristic and is limited within a predetermined range. An impedance value XSof slope reactance of the first SVC is set smaller than impedance value XSof slope reactance of the second SVC.

Reactive power compensator

A capacitor bank unit includes three capacitor banks that have respective capacitances that are multiples of a basic capacitance in accordance with a number sequence of the n-th power of 2. One of the capacitor banks has the basic capacitance, remaining two of the capacitor banks includes two subbanks each. The capacitance of a subbank is set to a capacitance that is a multiple of the basic capacitance in accordance with a number sequence of the m-th power of 2. When any one of the capacitor banks fails, each of capacitor banks following the failed capacitor bank substitutes for a capacitor bank located immediately before itself.

In a system stabilizing control system of controlling reactive power by a reactive power compensating device according to a voltage variation of an electric power system in which a capacitor is connected to a bus through a breaker, when the bus voltage drops, the capacitor is closed through the breaker to suppress a leading compensation reactive power amount caused by the reactive power compensating device, and when the bus voltage rises, the capacitor is disconnected through the breaker to suppress a lagging compensation reactive power amount caused by the reactive power compensating device.

System stabilization control system

A SVC control section detects a bus voltage from an instrument transformer, and adjusts reactive power generated by a SVC according to the detected bus voltage. A cooperative control section generates a control command for controlling the interconnection and parallel-off of a phase lead capacitor and a phase lag reactor on the basis of the amount of reactive power generated by the SVC and the bus voltage detected by the instrument transformer and a voltage sensor. A voltage comparator compares the bus voltage with a predetermined threshold voltage set to a voltage lower than a lower limit value of a steady state fluctuation range of the bus voltage and outputs the comparison result to a circuit breaker control section. When the bus voltage is lower than the threshold voltage, the circuit breaker control section locks the control command from the cooperative control section.

Power system control apparatus and power system control method

A reactive power control apparatus for an AC power system includes a reactive power compensation device, a compensation capacitor device and a compensation capacitor control device. The compensation capacitor control device includes a detection voltage output circuit which outputs a bus detection voltage after the clearing of a voltage drop abnormality, corresponding to the AC voltage of a system bus after the voltage drop abnormality that occurred in the AC power system has been cleared, and a compensation capacitor control circuit which controls the connection status of a compensation capacitor with respect to the system bus. The compensation capacitor control circuit controls the connection status of the compensation capacitor with respect to the system bus, on the basis of the voltage level of the bus detection voltage after the clearing of the voltage drop abnormality.

Reactive power control apparatus for AC power system

In a conventional reactive-power compensator using a static reactive-power compensator (SVC), there are many cases in which the SVC is operating in a state in which it generates an amount of reactive power equivalent to a large part of its capacity. When an unforeseen large voltage fluctuation occurs in this state, the SVC can not sufficiently generate the amount of reactive power required to mitigate the voltage fluctuation. In some cases, such a voltage fluctuation can not be brought under control. To address this situation, a reactive-power compensator utilizes a reactive-power control apparatus that includes a comparison voltage generator for generating, for a control target voltage and to mitigate voltage fluctuation, a comparison voltage restricted within predetermined limits and obeying a predetermined time-lag characteristic. A differential voltage generator generates a differential voltage that is the difference between the comparison voltage and the control target voltage. A reactive-power control device controls, in response to the differential voltage, control-target reactive power generated by an SVC, at a time-related characteristic faster than the time-lag characteristic for the comparison voltage.

Reactive-power control apparatus and reactive-power compensator using the same

In a control system for a static var compensator that performs phase control of a current of a reactor for each phase by a thyristor and thus controls reactive power, a detecting unit that detects a tertiary harmonic current flowing through each phase of the static var compensator is provided, and on the basis of the tertiary harmonic current flowing through each phase detected by the detecting unit, the thyristor of each phase is controlled so that the quantity of generated tertiary harmonic current of each phase becomes equal, and therefore an outflow of the tertiary harmonic current toward a system can be restrained by an inexpensive method.

Control system for static VAR compensator

A gene-mutated animal such as a mouse which comprises a mutant prsenilin-1 gene comprising a DNA having a sequence encoding a mutant presenilin-1 protein in which an amino acid is substituted with a different amino acid in an amino acid sequence of a presenilin-1 protein; for example, a mutant presenilin protein in which isoleucine at position 213 is substituted with an amino acid other than isoleucine, e.g., threonine, in a mouse presenilin-1 protein. The animal is useful as an animal model which has pathological conditions closer to a human patient with Alzheimer's disease.

Knockin gene-mutated mouse comprising a mutant presenilin-1 gene

For a load connected to the connection points of first and second mechanical bypass switches connected to first and second power supply systems, respectively, and a semiconductor switch connected in parallel with the second bypass switch, the power supply is switched from the first power supply system to the second power supply system, the first bypass switch is opened, and a semiconductor switch conducts whereby current through the first bypass switch is commutated to flow through the semiconductor switch, and then the second bypass switch is closed, whereby the load is switched and connected to the second power supply system.

Power supply system switching device and method of switching between power supply system

A power transfer device includes a first current transferring section connected between a first AC power source and a load, a second current transferring section with first and second switches which have opposite conduction directions, connected in parallel, and connected between a second AC power source and the load; a current detector for detecting a current flowing from the first AC power source to the load; a generator for generating a power transfer signal instructing transfer from the first AC power source to the second AC power source; a current direction estimator for estimating the direction of a current which flows from the first AC power source to the load when the second current transferring section enters the conduction state after a time period; and a conduction signal generator for causing one of the first and second switches to be conductive, so that the current flowing from the first AC power source to the load is cancelled, and, thereafter, causing the other of the first and second switches to be conductive.

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Tokyo, Japan

Masatoshi Takeda