Nissan Motor Company Limited

Mitsuhiro Shouji

Kengo Fujiwara

Hiromichi Kawamura

Takahiro Mizuguchi

Tetsuro Kojima

Naoki Takahashi

Yosuke Fukunaga

Akiko Nihei

Shun Kitauchi

Takayuki Kima

Provided is an electric motor control method includes: calculating a second torque command value by correcting the first torque command value by a vibration compensation torque for suppressing vibration in an electric motor rotation speed; limiting the vibration compensation torque based on a limit request suggesting amount suggesting a situation in which suppression of vibration in the electric motor rotation speed is to be limited; determining a limit level representing a degree of limit on the vibration compensation torque; and calculating a voltage command value by feeding back a torque suggesting amount suggesting an electric motor torque to the second torque command value. In the torque control step, a feedback gain of the torque suggesting amount is determined with reference to the limit level.

Electric motor control method and electric motor control device

An electric motor control apparatus that alternately switches modulation mode between an asynchronous PWM control, which controls an electric motor by fixing a PWM frequency, and a synchronous PWM control, which controls the electric motor by making the PWM frequency proportional to a drive frequency of the electric motor, wherein when switching the modulation mode, a compensation value is calculated based on a state quantity, which correlates with a component in a rotating coordinate system of a voltage applied to the electric motor and is obtained immediately before switching, and the voltage immediately after switching is compensated for by the compensation value.

Electric motor control apparatus and electric motor control method

A motor control method for controlling a motor by using an applied AC voltage converted from a DC voltage with an inverter driven by a PWM control, the motor control method includes: calculating a voltage command value for the inverter in order to achieve a desired torque output in the motor; calculating a compensation gain configured to maintain a linear relation between the voltage command value and the applied AC voltage according to a modulation factor indicating a ratio of the applied AC voltage to the DC voltage before and after a conversion in the inverter; limiting the compensation gain using an upper limit value; calculating a compensation voltage command value by multiplying the voltage command value by the limited compensation gain; and applying the applied AC voltage to the motor by driving the inverter using the compensation voltage command value; wherein the upper limit value is set so that the upper limit value become smaller when the modulation factor changes significantly.

Motor control method and motor control apparatus

A power control method for calculating a duty command value to be used for a PWM control, generating a PWM signal corresponding to a comparison result between the duty command value and a carrier signal, and applying a PWM voltage to a load by driving an inverter based on the PWM signal. The power control method comprises obtaining a compensation amount according to a phase shift generated in the PWM voltage so as to compensate for the shift, correcting the compensation amount according to a cycle of the carrier signal, and correcting the duty command value depending on whether a strength of the carrier signal is increasing or decreasing using the corrected compensation amount.

Power control method and power control apparatus

An electric machine control method includes: calculating a voltage command value based on a torque command value to an electric machine; calculating a modulation rate based on a power-supply voltage and the voltage command value; calculating a compensation gain in accordance with the modulation rate, the compensation gain being used to linearize a relationship between a magnitude of the voltage command value and a magnitude of a fundamental wave component of an output voltage to the electric machine; calculating a compensated voltage command value based on the voltage command value and the compensation gain; controlling the output voltage to the electric machine based on the compensated voltage command value; and limiting the compensation gain to be equal to or less than a predetermined upper limit.

Electric machine control method and electric machine control device

A controlling device () for executing either one of a current vector control and a voltage phase control such that supply power to an electric machine () is controlled in accordance with an operating state of the electric machine () calculates a voltage command value for the voltage phase control based on a voltage norm command value indicative of a magnitude of a supply voltage to the electric machine () and a voltage phase command value indicative of a phase of the supply voltage. The controlling device () calculates a state amount of either one of magnetic flux generated in the electric machine () and a parameter correlated to the magnetic flux, based on a current supplied to the electric machine () and changes the voltage norm command value in accordance with the state amount.

Electric machine controlling method and electric machine controlling device

A control apparatus for controlling an electrical unit driven by AC power, the control apparatus comprising a pair of switching elements configured to convert power from a power source into AC power and supply the AC power to the electrical unit. The control apparatus comprises the steps of generating a PWM signal on the basis of the duty command value calculated by the calculation unit and a carrier signal for performing the PWM control; controlling the AC power supplied to the electrical unit by switching a connection state of the switching element on the basis of the PWM signal generated by the generating unit; determining whether the carrier signal increases or decreases; and adjusting a switching timing of the switching element by correcting the duty command value calculated by the calculation unit on the basis of whether the carrier signal is increasing or decreasing determined by the determination unit.

Control apparatus and control method

An electric motor control device includes: a motor constant generator configured to generate a motor constant by using a temperature; a current control unit configured to generate a current command value to an electric motor based on the motor constant and a torque command value and execute a current control mode; a voltage phase control unit configured to calculate a torque estimation value of the electric motor and execute a voltage phase control mode in which a feedback operation is performed for a voltage phase based on the difference between the torque estimation value and the torque command value; and a control mode switching unit configured to switch to the voltage phase control mode in a high rotation area where a flux weakening control is performed. The torque estimation value is calculated using the motor constant common to generation of the current command value in the current control mode.

Electric motor control device and electric motor control method

An electric motor control device that performs a voltage phase control includes a voltage generator configured to calculate a d-q axis voltage command value, a stabilization filter having first to fourth filters determined based on a transfer characteristic from an applied voltage to an output electric current and configured to remove resonance characteristics in the d-q axis electric current, and a voltage application unit configured to apply an AC voltage to the electric motor based on the final d-q-axis voltage command value. The stabilization filter is configured to generate the final d-axis voltage command value based on a result obtained by using the first and second filters for each of the d-axis and the q-axis voltage command values and generate the final q-axis voltage command value based on a result obtained by using the third and fourth filters for each of the d-axis and the q-axis voltage command values.

An inverter control device includes an inverter; a command value calculator; a phase compensator; an inverter controller; a d-q axes non-interference voltage command value calculator for calculating a d-q axes non-interference voltage command value to cancel out interference voltages and for outputting the d-q axes non-interference voltage command value to the command value calculator; and a reverse phase. The phase compensator calculates the amount of phase lead based on the rotation speed and a phase compensation time set in order to obtain a predetermined phase margin, and compensates for a phase based on characteristics inherent in the motor, by the amount of phase lead. The reverse phase compensator compensates for a phase of the d-q axes non-interference voltage command value by the same amount of compensation as the amount of phase lead in the opposite direction to the phase compensated for by the phase compensator.

Inverter control device and inverter control method

An inverter control device is equipped with an inverter and a command value calculation unit calculates command values for the alternating current voltage output from the inverter. A phase compensation unit compensates the phase of the command values or the phase of the detected values. An inverter control unit controls the inverter on the basis of the command values or detected values that have been compensated by the phase compensation unit. A motor rotational velocity detector detects the rotational velocity of a motor. The phase compensation unit calculates the phase lead amount on the basis of a phase compensation time that is set for the purpose of obtaining a prescribed phase margin and on the basis of the rotational velocity and, in accordance with the phase lead amount, compensates the phase that is based on the specific characteristics of the motor.

A controllerperforms a control operation in a cycle based on a carrier frequency fc of a carrier, specifically, at timings corresponding to the peaks and troughs of the carrier signal. Moreover, in the case where the carrier frequency fc is switched, a disturbance estimation part forming the controllerupdates control constants that are used for disturbance estimation and are dependent on the control operation cycle, in a control operation performed one cycle after a control operation immediately after the switching of the carrier frequency fc.

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Kanagawa, Japan

Mitsuhiro Shouji