Abstract: A motor drive device is a device that controls torque generated by a motor, based on a d-axis current and a q-axis current, to drive the motor. The motor drive device includes a d-axis current instruction generating unit that calculates a first d-axis current instruction, a current instruction correcting unit that generates a positive correction quantity that is added to the first d-axis current instruction when a voltage across terminals of the motor is equal to or larger than a given value, and a voltage feedback control unit that generates a negative correction quantity that is added to the first d-axis current instruction to prevent the voltage across the terminals of the motor from exceeding a given maximum output voltage. The motor drive device controls the torque, based on a second d-axis current instruction created by adding the positive correction quantity and the negative correction quantity to the first d-axis current instruction and on a q-axis current instruction.

Abstract: A motor control device is connected to a power converter that performs power conversion from DC power to AC power and controls driving of an AC motor driven using the AC power, and the motor control device includes a carrier wave generation unit that generates a carrier wave, a carrier wave frequency adjustment unit that adjusts a frequency of the carrier wave, and a gate signal generation unit that performs pulse width modulation on a voltage command according to a torque command using the carrier wave and generates a gate signal for controlling an operation of the power converter, in which a phase difference between the voltage command and the carrier wave is randomly changed.

Abstract: Provided are an electric motor control device and an electric motor control method with high reliability capable of performing noise reduction control (or sensorless control) by superimposing a radio-frequency voltage and capable of performing compensation of a dead time of an inverter with a minimum necessary configuration.

Abstract: There is provided a synchronous machine control device capable of improving the performance of a motor without complicating a control system. The synchronous machine control device controls a power converter (2) that supplies electric power to a synchronous machine (1). The synchronous machine control device includes a first magnetic flux command computation unit (21) that computes a first magnetic flux command value (?d*, ?q*) from a current command value (Id*, Iq*) of the synchronous machine (1), a magnetic flux estimation unit (23) that estimates a magnetic flux value (?dc, ?qc) of the synchronous machine (1) from a current detection value (Idc, Iqc) of the synchronous machine (1), and a voltage computation unit (19) that creates a voltage command value (Vd*, Vq*) of the power converter such that the first magnetic flux command value (?d*, ?q*) coincides with the magnetic flux value (?dc, ?qc).

Abstract: A device according to an embodiment includes an inverter main circuit; a detector configured to detect a current of an output line of the inverter main circuit; a starting time controller comprising a rotational phase angle estimator configured to calculate, based on a current response value detected by the detector, a value corresponding to a rotational phase angle of a motor connected to the inverter main circuit in a stationary reference frame, and a rotational speed estimator configured to calculate a value corresponding to a rotational speed of the motor by using the value corresponding to the rotational phase angle when the inverter main circuit is started; and a regular time controller configured to calculate, with the value corresponding to the rotational speed as an initial value, an estimated rotational phase angle of the motor in a rotating reference frame.

Abstract: An inverter control apparatus and a motor drive system includes an inverter main circuit that drives a synchronous motor; an electric-current detector that detects an electric current flowing between the inverter main circuit and the synchronous motor; a command generator that generates an electric-current command value of an output electric current that is output from the inverter main circuit to the synchronous motor, in accordance with a torque command that is supplied externally; and an electric-current controller that generates a voltage command value for the inverter main circuit so that the electric-current command value and a detected electric-current value detected in the electric-current detector are equal to each other. The command generator generates the electric-current command value so that a fundamental wave current that is equal to or greater than a threshold is supplied to the synchronous motor, in driving the inverter main circuit.

Abstract: A device according to an embodiment includes an circuit; a detector for detecting a current response output from the circuit; a vector converter for converting the current response into a d-axis current and a q-axis current by using a rotational phase angle of a motor connected to the circuit; a calculator for calculating, based on a torque command and a current phase angle command, a current amplitude command of the current response output from the circuit; a dq-axes converter for calculating a d-axis current command and a q-axis current command from the current amplitude command and the current phase angle command; and a controller for calculating a voltage command so that the d-axis current command and the q-axis current command are equal to the d-axis current and the q-axis current.

Abstract: A device according to an embodiment including a command generator that generates a current command value; a detector that detects a current value to be outputted from an inverter to an motor; a generator that generates a gate command to the inverter, and obtains an output voltage target vector of the inverter based on the gate command; an estimator that obtains a rotary phase angle estimated value of the motor based on the detected current value and the output voltage target vector; and a polarity determination part that, with supply of a current in synchronism with a rotor frequency of the motor, performs determination of a magnet magnetic pole using a generated magnetic flux or voltage in synchronism with the generated rotor frequency or both of them, and outputs a correction value for the rotary phase angle estimated value based on a result of the determination.

Abstract: A drive system of an embodiment includes an inverter for driving an electric motor; a detector that detects an electric current value output from the inverter; command generators that generate an electric current command value corresponding to an electric current to be supplied to the electric motor and a gate command of the inverter so that the electric current command value matches the electric current value; calculators that calculate an voltage target vector of the inverter and a rotation phase estimation value of the electric motor based on the electric current value and the voltage target vector, in an initial estimation of when activating the inverter. The electric current command value in the initial estimation is a value to supply an electric current for magnetically saturating a rotor of the electric motor, and a dynamic inductance of the electric motor used for calculating the rotation phase estimation value is a value of when the rotor of the electric motor is magnetically saturated.

Abstract: A device according to an embodiment includes an inverter main circuit; a detector configured to detect a current of an output line of the inverter main circuit; a starting time controller comprising a rotational phase angle estimator configured to calculate, based on a current response value detected by the detector, a value corresponding to a rotational phase angle of a motor connected to the inverter main circuit in a stationary reference frame, and a rotational speed estimator configured to calculate a value corresponding to a rotational speed of the motor by using the value corresponding to the rotational phase angle when the inverter main circuit is started; and a regular time controller configured to calculate, with the value corresponding to the rotational speed as an initial value, an estimated rotational phase angle of the motor in a rotating reference frame.

Abstract: A device according to an embodiment includes an circuit; a detector for detecting a current response output from the circuit; a vector converter for converting the current response into a d-axis current and a q-axis current by using a rotational phase angle of a motor connected to the circuit; a calculator for calculating, based on a torque command and a current phase angle command, a current amplitude command of the current response output from the circuit; a dq-axes converter for calculating a d-axis current command and a q-axis current command from the current amplitude command and the current phase angle command; and a controller for calculating a voltage command so that the d-axis current command and the q-axis current command are equal to the d-axis current and the q-axis current.

Abstract: An inverter control apparatus and a motor drive system includes an inverter main circuit that drives a synchronous motor; an electric-current detector that detects an electric current flowing between the inverter main circuit and the synchronous motor; a command generator that generates an electric-current command value of an output electric current that is output from the inverter main circuit to the synchronous motor, in accordance with a torque command that is supplied externally; and an electric-current controller that generates a voltage command value for the inverter main circuit so that the electric-current command value and a detected electric-current value detected in the electric-current detector are equal to each other. The command generator generates the electric-current command value so that a fundamental wave current that is equal to or greater than a threshold is supplied to the synchronous motor, in driving the inverter main circuit.

Abstract: A device according to an embodiment including a command generator that generates a current command value; a detector that detects a current value to be outputted from an inverter to an motor; a generator that generates a gate command to the inverter, and obtains an output voltage target vector of the inverter based on the gate command; an estimator that obtains a rotary phase angle estimated value of the motor based on the detected current value and the output voltage target vector; and a polarity determination part that, with supply of a current in synchronism with a rotor frequency of the motor, performs determination of a magnet magnetic pole using a generated magnetic flux or voltage in synchronism with the generated rotor frequency or both of them, and outputs a correction value for the rotary phase angle estimated value based on a result of the determination.

Abstract: An inverter controller according to an embodiment has an inverter main circuit, current detectors, a current command value calculator, a voltage command value calculator and an estimator. The inverter main circuit is capable of being electrically connected to a rotary drive target. The current detectors detect current values output from the inverter main circuit. The current command value calculator calculates current command values with which an output voltage output from the inverter main circuit becomes equal to or more than a target value. The voltage command value calculator calculates voltage command values with which the current values become equal to the current command values. The estimator calculates an estimated rotational phase angle of the rotary drive target, based on the voltage command values and the current values.

Abstract: A drive system of an embodiment includes an inverter for driving an electric motor; a detector that detects an electric current value output from the inverter; command generators that generate an electric current command value corresponding to an electric current to be supplied to the electric motor and a gate command of the inverter so that the electric current command value matches the electric current value; calculators that calculate an voltage target vector of the inverter and a rotation phase estimation value of the electric motor based on the electric current value and the voltage target vector, in an initial estimation of when activating the inverter. The electric current command value in the initial estimation is a value to supply an electric current for magnetically saturating a rotor of the electric motor, and a dynamic inductance of the electric motor used for calculating the rotation phase estimation value is a value of when the rotor of the electric motor is magnetically saturated.

Abstract: A power conversion device includes a carrier generating unit, a setting unit, a PWM signal generating unit, and a power conversion unit. The carrier generating unit generates a carrier of a particular set carrier frequency during a certain continuation time. The setting unit sets the continuation time to be random and sets one carrier frequency among a plurality of mutually-different carrier frequencies as the set carrier frequency. The PWM signal generating unit generates a PWM signal based on the carrier generated by the carrier generating unit. The power conversion unit executes a power conversion based on the PWM signal and supplies converted power to a load.

Abstract: An inverter controller according to an embodiment has an inverter main circuit, current detectors, a current command value calculator, a voltage command value calculator and an estimator. The inverter main circuit is capable of being electrically connected to a rotary drive target. The current detectors detect current values output from the inverter main circuit. The current command value calculator calculates current command values with which an output voltage output from the inverter main circuit becomes equal to or more than a target value. The voltage command value calculator calculates voltage command values with which the current values become equal to the current command values. The estimator calculates an estimated rotational phase angle of the rotary drive target, based on the voltage command values and the current values.

Abstract: An inverter control device according to an embodiment includes an inverter main circuit, a current instruction generator, a voltage instruction generator, an estimator, a high-frequency wave superimposer. The inverter main circuit is electrically connectable to a predetermined rotational drive target. The current instruction generator generates a current instruction. The voltage instruction generator generates a voltage instruction causing a current output from the inverter main circuit to be equal to the current instruction. The estimator calculates an estimation rotational phase angle of the rotational drive target. The high-frequency wave superimposer superimposes a high-frequency wave on the current instruction or the voltage instruction according to a relation between a feature amount of the rotational drive target and a threshold.

Abstract: An embodiment of an electric vehicle drive apparatus includes a rotary electric motor, an electromagnet apparatus, an electric motor controller, and an electromagnet controller. The rotary electric motor drives at least one wheel. The electromagnet controller generates at least one of an attraction force between a rail and a bogie, and a propulsion force. The electromagnet controller controls the electromagnet apparatus. The rotary electric motor and the electromagnet apparatus are provided on the same bogie.

Abstract: A control system for controlling a synchronous motor having a magnet in a rotor includes an inverter configured to output an AC current for driving the motor, a gate command generating unit configured to generate a gate command for controlling the inverter, a current detecting unit configured to detect the AC current output by the inverter, a magnetic pole position estimating unit configured to estimate a magnetic pole position based on the AC current detected by the current detecting unit and generate an estimation signal, a current command generating unit configured to generate a current command and an estimation command for controlling the inverter to output an AC current with a predetermined level, and a magnetic polarity determination unit configured to determine the polarity of the magnet based on the estimation signal.