Daihen Corporation

Kyoto University

Nagaoka University of Technology

Dauhen Corporation

National University Corporation Nagaoka University of Technology

Nobuyuki Hattori

Akihiro Ohori

Hiroki Munechika

Ryuhei Nishio

Koji Matsunaga

Daisuke Tsukiyama

Kenji Hirata

Noriyuki Morotomi

Yoshito Ohta

A grid interconnection system for a power grid includes: a storage battery; a power conversion device that converts power from the storage battery into AC; and an interconnection control device that supplies power from a commercial power supply to a load and supplies power from the power conversion device to the load when the commercial power supply fails. When the commercial power supply is restored, the interconnection control device starts supply of power from the commercial power supply to the load, and stops supply of power from the power conversion device to the load after the supply of power from the commercial power supply to the load is started.

Grid interconnection system, interconnection control device and grid interconnection method

A measurement device that performs a predetermined measurement task together with a plurality of other measurement devices is provided. This measurement device is provided with a sampling phase generator for generating a sampling phase for instructing a timing of sampling, and a communication unit for communicating with at least one of the plurality of other measurement devices. The communication unit transmits the sampling phase generated by the sampling phase generator to at least one of the plurality of other measurement devices. The sampling phase generator is configured to generate a third sampling phase, using an operation that is based on a generated first sampling phase and a second sampling phase received by the communication unit from at least one of the plurality of other measurement devices.

Method for controlling devices provided with communication function, and device used in implementing the method

A signal processor is configured to perform a process equivalent to performing a series of fixed-to-rotating coordinate conversion, a predetermined process and then rotating-to-fixed coordinate conversion, while maintaining linearity and time-invariance. The signal processor performs a process given by the following matrix G: where F(s) is a transfer function representing the predetermined process, &#x3c9;is a predetermined angular frequency and j is the imaginary unit.

Signal processor, filter, control circuit for power converter circuit, interconnection inverter system and PWM converter system

An object is to provide a power system interconnection system and a method of installing the power system interconnection system that are able to supply a load with required power. A power system interconnection system comprises a storage battery an AC-DC power conversion device for the storage battery a charge and discharge station for an electric-powered automobile and an interconnection control device that are installed on a parking lot. The interconnection control device supplies a first load with power from at least one of the charge and discharge station and the AC-DC power conversion device in a case where the electric power system is in an emergency situation.

Power system interconnection system, and method of installing power system interconnection system

A power system includes a plurality of power conditioners, and a central management device that manages the plurality of power conditioners. The central management device includes a detector and an index calculator. The detector detects regulation subject power. The index calculator calculates an index for controlling individual output powers of the plurality of power conditioners such that the regulation subject power matches with target power. Each of the plurality of power conditioners includes a target power calculator and a controller. The target power calculator calculates the individual target power of the power conditioner based on an optimization problem using the index. The controller regulates the individual output power to the individual target power.

Electric power system

A measurement apparatus is used in cooperation with another equivalent measurement apparatus. Each measurement apparatus includes a change amount calculator for calculating a change amount of measured values, an average value generator for generating a first internal average value based on the change amount, and a communication unit for receiving a second internal average value that was generated by at least one other measurement apparatus. The average value generator generates a third internal average value, using a computation result based on at least the first and second internal average values.

Measurement apparatus and data processing method

A control circuit reduces switching loss by periodically stopping switching elements, and reduces the difference between the time for which positive switching elements are in on state and the time for which negative switching elements are in on state. The control circuit includes a command value signal generator generating command value signals Xu, Xv, and Xwfrom line voltage command value signals Xuv, Xvw, and Xwu, and includes a PWM signal generator generating PWM signals by the command value signals Xu, Xv, and Xw. The command value signals Xu, Xv, and Xware continuously at '0' for a predetermined period, and are continuously at '2' for another period. This enables reducing the difference between the period for which the PWM signals are low and the period for which they are high.

Inverter apparatus including control circuit employing two-phase modulation control, and interconnection inverter system including the inverter apparatus

A control circuit reduces switching loss by periodically stopping switching elements, and reduces the difference between the time for which positive switching elements are in on state and the time for which negative switching elements are in on state. The control circuit includes a command value signal generator generating command value signals Xu, Xv, and Xwfrom line voltage command value signals Xuv, Xvw, and Xwu, and includes a PWM signal generator generating PWM signals by the command value signals Xu, Xv, and Xw. The command value signals Xu, Xv, and Xware continuously at '0' for a predetermined period, and are continuously at '2' for another period. This enables reducing the difference between the period for which the PWM signals are low and the period for which they are highl.

Growing community of inventors

Osaka, Japan

Nobuyuki Hattori