Abstract: An electric motor control device includes an electronic control unit configured to perform switching control of a switching element of an inverter in PWM control mode when a modulation degree is less than a first predetermined value, perform switching control of the switching element in square wave control mode when the modulation degree is greater than or equal to a second predetermined value, and perform switching control of the switching element in intermediate control mode when the modulation degree is greater than or equal to the first predetermined value and less than the second predetermined value. The intermediate control mode uses a switching pattern in which, in a pulse pattern in the square wave control mode, a slit or a short pulse having the same width as the slit is formed according to whether a pulse is present at the time when a phase current crosses zero.

Abstract: There is provided a driving system including a motor; an inverter configured to drive the motor; a power storage device connected with the inverter via a power line; a smoothing capacitor mounted to the power line; a voltage sensor configured to detect a voltage of the smoothing capacitor; a current sensor configured to detect an electric current of each phase of the motor; and a control device configured to control the inverter, based on a detected value of the current sensor. The control device performs Fourier series expansion of a detected value of the voltage sensor to calculate an electrical first variation component of the voltage of the smoothing capacitor. The control device controls the inverter, such that the electrical first variation component of the voltage of the smoothing capacitor becomes equal to a value 0.

Abstract: A controller of an electrically powered vehicle includes an electronic control unit. The electronic control unit performs a switching control by a square wave control in a first switching mode when a rotation speed of the motor is equal to or higher than a first predetermined rotation speed. The electronic control unit performs the switching control by the square wave control in a second switching mode when the rotation speed of the motor is lower than the first predetermined rotation speed. The first predetermined rotation speed is a rotation speed lower than a first resonance region. The first switching mode is a mode of a switching pattern that suppresses LC resonance in the first resonance region. The second switching mode is a mode of a switching pattern that suppresses LC resonance in a second resonance region lower than the first predetermined rotation speed.

Abstract: A controller of an electrically powered vehicle includes an electronic control unit. The electronic control unit performs a switching control by a square wave control in a first switching mode when a rotation speed of the motor is equal to or higher than a first predetermined rotation speed. The electronic control unit performs the switching control by the square wave control in a second switching mode when the rotation speed of the motor is lower than the first predetermined rotation speed. The first predetermined rotation speed is a rotation speed lower than a first resonance region. The first switching mode is a mode of a switching pattern that suppresses LC resonance in the first resonance region. The second switching mode is a mode of a switching pattern that suppresses LC resonance in a second resonance region lower than the first predetermined rotation speed.

Abstract: An overall loss L during non-execution of intermittent boosting (in ordinary boosting) is calculated from losses L1 and L2 of motors and a loss LC of a boost converter during non-execution of intermittent boosting. The overall loss L during execution of intermittent boosting is calculated from the losses L1 and L2 of the motors and the loss LC of the boost converter during execution of intermittent boosting. A minimum loss-time boosting voltage Vtmp at which the overall loss L provides a minimum loss Ltmp is set to a target voltage VH*. The boost converter is then controlled in a control state corresponding to the minimum loss-time boosting voltage Vtmp.

Abstract: An overall loss L during non-execution of intermittent boosting (in ordinary boosting) is calculated from losses L1 and L2 of motors and a loss LC of a boost converter during non-execution of intermittent boosting. The overall loss L during execution of intermittent boosting is calculated from the losses L1 and L2 of the motors and the loss LC of the boost converter during execution of intermittent boosting. A minimum loss-time boosting voltage Vtmp at which the overall loss L provides a minimum loss Ltmp is set to a target voltage VH*. The boost converter is then controlled in a control state corresponding to the minimum loss-time boosting voltage Vtmp.

Abstract: A vehicle, including a motor having a rotor, a resolver that detects a rotation angle of the rotor and a control device, and a control method for the vehicle are provided. The control device executes rectangular-wave control over the motor using the rotation angle of the rotor, detected by the resolver, executes zero learning for learning a deviation between an origin of an actual rotation angle of the rotor and an origin of the detected rotation angle of the rotor, corrects the detected rotation angle of the rotor on the basis of a result of the zero learning, and, when the zero learning has not been completed yet, executes avoidance control for avoiding a rapid variation in output of the motor.

Abstract: A rotor position estimating device includes a voltage application unit, a current detecting unit and an estimating unit. The voltage application unit is configured to apply a d-axis voltage to an electric motor including a salient-pole rotor during a stop of the electric motor. The current detecting unit is configured to detect a q-axis current flowing through the electric motor at the time when the d-axis voltage is applied. The estimating unit is configured to estimate a rotor position during a stop of the electric motor on the basis of the q-axis current detected by the current detecting unit. The voltage application unit is configured to set a voltage application time in correspondence with peak timing at which the q-axis current reaches a peak in a transitional response characteristic of the q-axis current at the time when the d-axis voltage is applied.

Abstract: A vehicle, including a motor having a rotor, a resolver that detects a rotation angle of the rotor and a control device, and a control method for the vehicle are provided. The control device executes rectangular-wave control over the motor using the rotation angle of the rotor, detected by the resolver, executes zero learning for learning a deviation between an origin of an actual rotation angle of the rotor and an origin of the detected rotation angle of the rotor, corrects the detected rotation angle of the rotor on the basis of a result of the zero learning, and, when the zero learning has not been completed yet, executes avoidance control for avoiding a rapid variation in output of the motor.

Abstract: A rotor position estimating device includes a voltage application unit, a current detecting unit and an estimating unit. The voltage application unit is configured to apply a d-axis voltage to an electric motor including a salient-pole rotor during a stop of the electric motor. The current detecting unit is configured to detect a q-axis current flowing through the electric motor at the time when the d-axis voltage is applied. The estimating unit is configured to estimate a rotor position during a stop of the electric motor on the basis of the q-axis current detected by the current detecting unit. The voltage application unit is configured to set a voltage application time in correspondence with peak timing at which the q-axis current reaches a peak in a transitional response characteristic of the q-axis current at the time when the d-axis voltage is applied.

Abstract: A plurality of current sensors are provided to correspond to a plurality of inverter circuits for driving a plurality of motor generators, respectively. Zero point adjustment of each current sensor is executed in a non-energized state recognized based on a stop of operation of the corresponding inverter circuit and when noise influence is determined to be small based on stops of operations of the other inverter circuits in the same casing. As a result, it is possible to avoid a risk of performing the zero point adjustment in a state in which an output of the current sensor is not exactly a value corresponding to zero current due to the noise influence from the other inverter circuits. In this way, it is possible to highly accurately execute the zero point adjustment of the current sensor for measuring motor driving current.

Abstract: A fuel cell catalyst containing platinum, zinc, and at least one of nickel and iron.

Abstract: A boost converter boosts a DC voltage of a DC power supply. An inverter converts the output voltage of the boost converter into an AC voltage. A control device that controls the boost converter reduces an output voltage instruction value of the boost converter when the rotation speed of the AC motor decreases and an absolute value of a variation rate of the rotation speed is not less than a predetermined value. The inverter is controlled in the control mode selected from a plurality of control modes including three modes of a sine wave PWM control mode, an overmodulation PWM control mode and a rectangular wave control mode. The control device of the boost converter reduces the output voltage instruction value of the boost converter only when the control mode of the inverter is the rectangular wave control mode or the overmodulation control mode.

Abstract: A composition for use as a catalyst in, for example, a fuel cell, the composition comprising platinum, copper, and nickel, wherein the concentration of platinum therein is greater than 50 atomic percent and less than 80 atomic percent, and further wherein the sum of the concentrations of platinum, copper and nickel is greater than 95 atomic percent.

Abstract: The present invention is directed to a composition for use as a catalyst in, for example, a fuel cell, the composition comprising platinum and copper, wherein the concentration of platinum is greater than 50 atomic percent and less than about 80 atomic percent, and further wherein the composition has a particle size which is less than 35 angstroms. The present invention is further directed to various methods for preparing such a composition.

Abstract: A fuel cell catalyst comprising platinum, chromium, and copper, nickel or a combination thereof. In one or more embodiments, the concentration of platinum is less than 50 atomic percent, and/or the concentration of chromium is less than 30 atomic percent, and/or the concentration of copper, nickel, or a combination thereof is at least 35 atomic percent.

Abstract: An improved metal alloy composition for a fuel cell catalyst containing platinum, manganese, and cobalt.

Abstract: A plurality of current sensors are provided to correspond to a plurality of inverter circuits for driving a plurality of motor generators, respectively. Zero point adjustment of each current sensor is executed in a non-energized state recognized based on a stop of operation of the corresponding inverter circuit and when noise influence is determined to be small based on stops of operations of the other inverter circuits in the same casing. As a result, it is possible to avoid a risk of performing the zero point adjustment in a state in which an output of the current sensor is not exactly a value corresponding to zero current due to the noise influence from the other inverter circuits. In this way, it is possible to highly accurately execute the zero point adjustment of the current sensor for measuring motor driving current.

Abstract: A fuel cell catalyst comprising platinum, titanium and tungsten. In one or more embodiments, the concentration of platinum is less than 60 atomic percent, and/or the concentration of titanium is at least 20 atomic percent, and/or the concentration of tungsten is at least 25 atomic percent.

Abstract: A boost converter boosts a DC voltage of a DC power supply. An inverter converts the output voltage of the boost converter into an AC voltage. An AC motor is driven by the output voltage of the inverter. A control device which controls the boost converter reduces an output voltage instruction value of the boost converter in the case where the rotation speed of the AC motor is decreased and an absolute value of a variation rate of the rotation speed is not less than a predetermined value. The inverter is controlled in the control mode selected from a plurality of control modes including three modes of a sine wave PWM control mode, an overmodulation PWM control mode and a rectangular wave control mode. The control device of the boost converter reduces the output voltage instruction value of the boost converter only in the case where the control mode of the inverter is the rectangular wave control mode or the overmodulation control mode.