Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric Corporation

Mitsubushi Denki Kabushiki Kaisha

Mitsubishi Denki Kabsuhiki Kaisha

Sadayuki Inoue

Ken Onishi

Junko Ishimoto

Tohru Inoue

Masako Asamura

Tomohiro Ueda

Junko Shinohara

Taketoshi Hibi

Tatsuo Yamasaki

Makoto Kumano

Nobuyoshi Okumura

Ikuo Ohkuma

Tomihiro Takano

Koki Matsumoto

Hideki Kaneko

Haruhisa Inoue

Masahiro Tsujishita

Takahiko Nakamura

Takahiro Kato

Tetsuro Shida

Toshifumi Fujii

Soichiro Matsumoto

Masako Yamada

Toshimitsu Sato

Keishi Matsuda

Tsuyoshi Kasaura

Yoshinori Asamura

Takashi Fujiwara

Satoshi Hara

Makiko Kise

Mitsuru Matsui

Tomoki Takegami

Satoshi Kurahashi

Junji Sukeno

Hiroshi Onishi

Kazufumi Tanaka

Kimitoshi Hongo

Yuki Itogawa

Ikuo Okuma

Hideki Kawano

Ikuo Ookuma

Naotoshi Maeda

Kyoto Fujii

Xiaowei Dui

An operation plan creation circuit creates a power target value of each of a plurality of distributed power supplies on the basis of information received by a communication circuit and capacities of the plurality of distributed power supplies a control parameter generation circuit generates a control parameter of the virtual synchronous generator control implemented in a static inverter of each of the distributed power supplies or information necessary for generating the control parameter. The communication circuit receives measurement information of each of the distributed power supplies, and transmits a control command to each of the distributed power supplies. The control parameter generation circuit generates the control parameter or the information necessary for generating the control parameter on the basis of the information received by the communication circuit, the capacities of the plurality of distributed power supplies, and the power target value of each of the distributed power supplies.

Distributed power supply management device

A virtual synchronous generator controller included in a controller of a power convertor generates a first command value of a frequency of a second voltage and a second command value of a phase of the second voltage by making an active power value and an active power target value correspond respectively to electrical energy and mechanical energy of a motion equation of a rotor of a synchronous generator to simulate an operation of the synchronous generator. When a turn-on condition is satisfied, a determination unit switches a connection state from a non-conduction state to a conduction state by controlling a relay that causes the connection state between an inverter and an AC power system to be selectively switched between the conduction state and the non-conduction state.

Power convertor

A power conversion device includes a converter, an inverter, a converter control circuit, a virtual synchronous generator control circuit to impart a transient characteristic of a synchronous generator to the inverter, and an inverter control circuit to control the inverter. The virtual synchronous generator control circuit calculates a switching frequency at which charge/discharge of the distributed power source is switched, based on information necessary for virtual synchronous generator control. The converter control circuit uses the switching frequency to create a frequency range of AC system voltage for providing a dead zone in which charge/discharge power of the distributed power source is zero in a drooping characteristic of the power conversion device, or a hysteresis in switching of charge/discharge of the distributed power source. The converter control circuit performs control such that charge/discharge power of the distributed power source becomes zero in the frequency range.

Power conversion device

A power conversion device inputs or outputs a power for changing a state quantity of a distribution grid to which a voltage source device is connected, to or from the distribution grid. A grid control unit calculates a power command value of the power conversion device such that a drooping characteristic is provided for compensating for a deviation from a control target of the state quantity obtained from an output of a detector. A frequency characteristic of control computation for calculating a power command value from the deviation in the system control unit is defined such that a first control gain value in a first frequency range including direct current is set corresponding to a slope of the drooping characteristic, and a second control gain value in a second frequency range including higher frequencies than the first frequency range is set to be lower than the first control gain value.

Grid system and control device of grid system

A grid system includes a voltage source, a plurality of consumers connected to the voltage source via a distribution grid, and a grid control unit for transmitting a power command value to a device provided to each consumer. The consumer is provided with a power generation device, a power storage device, and power conversion devices for converting respective powers of the power generation device and the power storage device. The power conversion devices respectively include power command correction means for correcting the power command value from the grid control unit on the basis of the frequency of voltage at a power receiving point Xwhich is a connection point between the consumer and the distribution grid. The power command value for the power conversion device of the power generation device is set to be greater than the power command value for the power conversion device of the power storage device.

Grid system, control device, control method for grid system, and power conversion device

An inverter converts power outputted from a distributed power supply into AC power, and outputs to an AC system. An inverter control circuit generates an AC voltage target value at a time of controlling the inverter, and generates a command value for control of the inverter as a voltage source. When the inverter is introduced into the AC system, the inverter control circuit sets a frequency of the AC voltage target value to a frequency of an AC voltage detected by an AC frequency detection circuit, and controls a phase of the AC voltage target value to be at least a leading phase with respect to the AC voltage of the AC system when a target value of the AC power is in a running direction.

Power conversion device including an inverter control circuit that controls a phase of an AC voltage target value

A control circuit includes a virtual synchronous generator control circuit to impart a transient characteristic of a synchronous generator to the inverter, a control parameter generating circuit to generate a control parameter for controlling the virtual synchronous generator control circuit, an inverter voltage control circuit to control the inverter as a voltage source, based on AC system voltage information input from the virtual synchronous generator control circuit, and a communication circuit to receive, from a management device that manages the distributed power source, a power target value of the distributed power source and information necessary for generating the control parameter. The control parameter generating circuit generates at least one of a speed adjustment rate and a damping coefficient to be used in the virtual synchronous generator control circuit, based on the power target value and the information necessary for generating the control parameter received by the communication circuit.

A solar cell power conversion device is disposed between a solar cell and a distribution system. A storage battery power conversion device is disposed between a storage battery and the distribution system. An effective voltage calculation circuit calculates an effective voltage of an AC voltage in the distribution system. Based on the effective voltage, a second control circuit and a fourth control circuit control active power and reactive power output from a first DC/AC conversion circuit and a second DC/AC conversion circuit, respectively. When a change in the effective voltage is caused by an operation of an SVR provided in the distribution system, the second and fourth control circuits control operations of the first and second DC/AC conversion circuits to suppress a change in the reactive power caused by the change in the effective voltage.

A device for controlling a storage battery system is provided. The device includes: a state information calculator configured to calculate state information on each of batteries of a plurality of storage battery modules; a conversion efficiency characteristics calculator configured to calculate a power conversion efficiency of each of DC/DC converters of the plurality of storage battery modules; and a storage battery module selector configured to select one or a plurality of storage battery modules to be used while the storage battery system is charged or discharged and to determine a charge power or a discharge power of each of the selected storage battery modules, based on the state information of the batteries and the power conversion efficiencies of the DC/DC converters.

Device and method for controlling a storage battery system

A solar cell power conversion device is disposed between a solar cell and a consumer premises distribution system. A storage battery power conversion device is disposed between a storage battery and the consumer premises distribution system. When an AC effective voltage in the consumer premises distribution system deviates from a voltage range defined in accordance with dead zone information transmitted from HEMS, system voltage stabilization control for returning the AC effective voltage to fall within the voltage range is performed by control of active power and reactive power that are output from a first DC/AC conversion circuit and a second DC/AC conversion circuit.

Power conversion device that receives dead zone information

A town storage battery power conversion device outputs an AC voltage to a distribution system during a power failure. Electric power generated by a solar cell installed in each consumer house is converted into an AC voltage by a solar cell power conversion device and output to a consumer premises distribution system to which a load is connected. In an autonomous operation during a power failure, an operation plan for a distributed power supply is updated in a cycle longer than a cycle of an operation plan for a town storage battery. In the autonomous operation, the town storage battery power conversion device changes an AC voltage frequency according to a difference between electric power output from the town storage battery and the operation plan. The solar cell power conversion device has a function of modifying a control target value for the solar cell according to the AC voltage frequency.

Power management system

When the AC voltage effective value at an interconnection point is higher than a first threshold voltage, a solar-panel power conversion device controls an output of reactive power so that the voltage at the interconnection point matches a first target effective voltage. When the power generated from an energy creation apparatus is higher than a first reference power and the AC voltage effective value at the interconnection point is higher than a second threshold voltage, then a storage-battery power conversion device controls an output of reactive power so that the voltage at the interconnection point matches a second target effective voltage.

Distributed power supply system

When a plurality of storage batteries is used by connecting them in parallel, since the progress of degradation differs among the storage batteries, a power conversion system includes a degradation information acquisition device for acquiring the degradation information of the storage batteries, a temperature information acquisition device for detecting the temperature information of the storage batteries, and a control device for controlling the storage battery power converter based on the degradation information of the storage batteries by the degradation information acquisition device and the temperature information of the storage batteries by the temperature information acquisition device so that the degradation states of the plurality of the storage batteries can be matched.

Power conversion system

In the case of performing self-sustained operation, when power conversion devices supply power to loads, all DC/AC conversion circuits of the power conversion devices are operated in a voltage control mode, and effective voltage (amplitude) of reference AC voltage as a control target for AC power outputted from each DC/AC conversion circuit under voltage control is adjusted in accordance with the power generation amount of a solar panel as a DC power supply, and the state of charge of a storage battery, thereby the amount of power supplied to the loads is controlled.

Provided are a solar panel (), a first DC/DC conversion circuit (), a DC/AC conversion circuit () connected via a DC bus (), a second DC/DC conversion circuit () for controlling bus voltage in the case of power outage, a first control section () having two kinds of control modes and controlling the first DC/DC conversion circuit (), a second control section () for controlling the second DC/DC conversion circuit (), and a third control section () for controlling the DC/AC conversion circuit (). The second control section () controls bus voltage in the case of power outage, and the first control section () switches the control mode based on information of the second control section ().

Growing community of inventors

Nagaokakyo, Japan

Sadayuki Inoue