Kabushiki Kaisha Yaskawa Denki

Other

Kentaro Inomata

Akira Yamazaki

Hidenori Hara

Masato Higuchi

Shinya Morimoto

Shingo Fukumaru

Mamoru Takaki

Takahiro Uchino

Joji Ebisu

Yoshiyasu Takase

Takashi Tanaka

Kotaro Takeda

Wataru Yoshinaga

Noor Aamir Baloch

Hengbin Rui

Takanori Iwaki

Takuya Naka

Tokuma Nakamichi

To provide a power conversion device that is effective for improving controllability of power in power conversion for multilevel voltage output. A power conversion device includes a switching circuit configured to supply a current to a motor by connecting and disconnecting a first point having a first potential, a second point having a second potential greater than the first potential, and a neutral point having a neutral potential between the first potential and the second potential to and from the motor, a neutral potential control unit configured to control the switching circuit in a manner to maintain the neutral potential within a target range, and a current control unit configured to increase a supply current to the motor without affecting a driving force generated by the motor at least when controlling the switching circuitby the neutral potential control unit.

Power conversion device and power conversion method

A power conversion device includes a power conversion circuit including a temperature sensor configured to detect a temperature at a sensor position and a switch configured to switch a connection on and off at a switch position separated from the sensor position; a loss calculation processing circuitry configured to calculate a power loss in the switch; a loss correction processing circuitry configured to correct a calculation result of the power loss on the basis of a detection result of the temperature at the sensor position; a temperature correction processing circuitry configured to correct the detection result of the temperature on the basis of the calculation result of the power loss; and a temperature estimation processing circuitry configured to estimate a temperature at the switch position on the basis of a corrected calculation result of the power loss and a corrected detection result of the temperature.

Power conversion device, temperature estimation method, and non-transitory computer readable storage medium with an executable program recorded thereon

A power conversion device connected in parallel to a second power conversion device including power conversion circuitry that performs power conversion by changing a connection state between first multiple lines on a primary side and second multiple lines on a secondary side, baseline selection circuitry that selects one of the second multiple lines on the secondary side as a baseline and partial modulation control circuitry that controls the power conversion circuitry to maintain a state in which the baseline is connected to one of the first multiple lines on the primary side and to change a connection state between other second multiple lines on the secondary side and the first multiple lines on the primary side, wherein the baseline selection circuitry switches a line selected as the baseline based on a switching timing used by second baseline selection circuitry of the second power conversion device to select a second baseline.

Power conversion device, power conversion system, and power conversion method

A power conversion device includes processing circuitry that estimates a magnet magnetic flux of an electric motor based on a d-axis magnetic flux generated in the electric motor, a d-axis inductance of the electric motor, and a d-axis current flowing in the electric motor, estimates a q-axis inductance of the electric motor based on a q-axis magnetic flux generated in the electric motor and a q-axis current flowing in the electric motor, estimates a drive force of the electric motor based on the magnet magnetic flux and the q-axis inductance, and corrects a current command such that the drive force follows a drive force command.

Power conversion device, power conversion method and program

A power conversion apparatus connectable in parallel to a second power conversion apparatus includes circuitry that generates a carrier wave, generates a pulse signal synchronized with the carrier wave, generates power that is based on a width of the pulse signal, obtains a monitor value corresponding to a circulating current circulating between the power conversion apparatus and the second power conversion apparatus, and based on the monitor value obtained while the power conversion circuitry is generating driving power, changes a period of the carrier wave to decrease the circulating current.

Power conversion apparatus, power conversion system, and method for converting power

A device includes: a first power conversion circuitry configured to convert primary-side power into secondary-side power; and a control circuitry configured to: generate a command value associated with the secondary-side power; calculate a limited command value by modifying the command value so that the command value is equal to or less than a secondary-side limit, wherein the first power conversion circuitry is controlled based on the limited command value; transmit the limited command value to a second power conversion device comprising a second power conversion circuitry connected in parallel to the first power conversion circuitry; receive, from the second power conversion device, information indicating an adjustment value, wherein the adjustment value is added to the limited command value for controlling the second power conversion circuitry; and modify the secondary-side limit based on a difference between a primary-side limit associated with the primary-side power and the adjustment value.

A matrix convertor includes a power convertor and a controller. The power convertor is disposed between a power system and a rotating electric machine, and includes a plurality of bidirectional switches. The controller is configured to control an exciting current flowing from the power convertor to the rotating electric machine so as to control a power factor on a side of the power system.

Matrix convertor, power generation system, and method for controlling power factor

A matrix converter includes a power converter and a controller. The power converter includes bidirectional switches each having a controllable conducting direction. The bidirectional switches are disposed between input terminals and output terminals. The input terminals are respectively coupled to phases of an AC power source. The output terminals are respectively coupled to phases of a load. The controller controls the bidirectional switches. A first commutation controller performs commutation control when the conducting direction is unidirectional. A second commutation controller performs the commutation control when the conducting direction is bidirectional. A selector selects between the first commutation controller and the second commutation controller to perform the commutation control based on a state of an output current from the power converter.

Matrix converter having first and second commutation controllers

A matrix converter according to an embodiment includes a voltage command corrector and a drive signal generator. The voltage command corrector corrects the magnitude of an output voltage command on the basis of amplitude variations of an input current from an AC power supply to a power converter, the amplitude variations being caused by a ripple component of the input current. The drive signal generator generates drive signals that turn ON/OFF a plurality of bidirectional switches on the basis of the output voltage command corrected by the voltage command corrector.

Matrix converter

Provided is a matrix converter including a power converter, a commutation controller, and a compensator. The power converter includes a plurality of bidirectional switches. The commutation controller performs one of a three-step commutation operation and a four-step commutation operation by the bidirectional switches as a switch source and the bidirectional switches as a switch destination when an input terminal to be connected to an output terminal is switched by on/off control of the bidirectional switches. The compensator compensates for an output voltage error generated when the input terminal to be connected to the output terminal is switched, based on a potential difference before and after the switching of the input terminal to be connected to the output terminal, an output current of the output terminal, and capacitance between input and output terminals of unidirectional switches.

Growing community of inventors

Kitakyushu, Japan

Kentaro Inomata