A motor control device including: a power supply voltage detection unit configured to detect a power supply voltage; a rotational angular velocity detection unit configured to detect a rotational angular velocity of the motor; a command value calculation unit configured to calculate a q-axis and d-axis current command values; a gain computation unit configured to compute, based on an upper limit value of power supply current supplied from a power supply to the motor, the power supply voltage, the rotational angular velocity, the q-axis current command value, and the d-axis current command value, a limit gain reducing the power supply current to the upper limit value or lower by limiting the q-axis current command value and the d-axis current command value; and a driving circuit configured to drive the motor, based on the q-axis current command value and the d-axis current command value limited by the limit gain.

A microcomputer includes a current command value setting unit configured to set a two-phase current command value in a two-phase rotating coordinate system for each of PWM cycles in a current control cycle, and an open-loop control unit configured to calculate a two-phase voltage command value for each of the PWM cycles, according to a motor voltage equation, based on the two-phase current command value for each of the PWM cycles that is set by the current command value setting unit and a rotation speed of an electric motor. The two-phase voltage command value is a command value of voltage that is to be applied to the electric motor.

A motor control device including: a power supply voltage detection unit configured to detect a power supply voltage; a rotational angular velocity detection unit configured to detect a rotational angular velocity of the motor; a command value calculation unit configured to calculate a q-axis and d-axis current command values; a gain computation unit configured to compute, based on an upper limit value of power supply current supplied from a power supply to the motor, the power supply voltage, the rotational angular velocity, the q-axis current command value, and the d-axis current command value, a limit gain reducing the power supply current to the upper limit value or lower by limiting the q-axis current command value and the d-axis current command value; and a driving circuit configured to drive the motor, based on the q-axis current command value and the d-axis current command value limited by the limit gain.

A rotary electrical machine includes a switch for supplying power to a field winding and a controller. A ratio of an on-time to a switching cycle of the switch, i.e., a duty ratio which is larger than the duty ratio corresponding to the field current that gives the maximum reduction amount of the inductance of the field winding with respect to an increasing amount of the field current in a range that the field current can take and which has a predetermined value less than 100%. The controller calculates the duty ratio on the condition that an upper limit of the duty ratio is set as the predetermined value and turns on/off the switch based on the calculated duty ratio, and sets the predetermined value to be larger as a rotation speed of a rotor is higher, or as a d-axis current flowing through an armature winding is larger.

The present invention relates to a motor driving apparatus and a home appliance comprising the same. The motor driving apparatus according to an embodiment of the present invention comprises: an inverter which converts a direct current power source of a DC stage capacitor to an alternating current power source and outputs the converted alternating power source to a motor by a switching operation; a DC stage resistance device arranged between the DC stage capacitor and the inverter; and a control unit which controls the inverter on the basis of phase current sampled by means of the DC stage resistance device, wherein the control unit controls the frequency of voltage applied to the motor or the rotation frequency of the motor to be synchronized with the sampling frequency of the phase current sampled via the DC stage resistance device. Accordingly, it is possible to accurately calculate the phase current flowing through the motor by means of the DC stage resistance device.

An apparatus for controlling an inverter to drive a motor includes: a current control processor generating a voltage command for generating d/q axis current detection values, which are obtained by measuring current supplied to the motor, to follow a d/q axis current command for driving the motor, the current control processor converting the voltage command, which is sampled according to a sampling frequency generated based on a voltage vector phase of the voltage command, into a voltage vector corresponding to a point on each vertex and each side of a hexagon in a voltage vector diagram to apply a resulting value to the inverter driving the motor; and a sample frequency computing processor computing the sampling frequency based on the voltage vector phase of the voltage command and a reference number of sampling times during one rotation period of the motor.

A motor control device including: an operation control part that generates a torque command based on an operation command, and controls a rotational position and/or rotational speed of the spindle; a current control part that generates an excitation current command to control secondary magnetic flux of the induction motor, and a torque current command to control torque of the induction motor based on the torque command; a change detection part that detects a change in operation command requiring increasing the secondary magnetic flux of the induction motor; a magnetic flux amplification part that performs magnetic flux amplification to temporarily increase the excitation current command or a magnetic flux command in the current control part, in a case of a change in the operation command being detected; and a gain change part that changes gain of the operation control part when performing magnetic flux amplification.

A variable magnetization machine control system comprising a controller configured to generate a reversely rotating d-axis/q-axis current vector trajectory during a change in a magnetization state of a variable magnetization machine to drive the variable magnetization machine at a predetermined speed while maintaining the driving voltage below a predetermined maximum magnitude.

A permanent-magnet-synchronous electric motor control device includes: a reference voltage value calculation unit for calculating a reference voltage value; an output voltage value calculation unit for calculating an output voltage value on the basis of a voltage command; a current weakening command calculation unit for calculating a current weakening command on the basis of the reference voltage value and the output voltage value; a voltage command calculation unit for calculating the voltage command on the basis of the current weakening command; and a power converter for supplying power to a permanent-magnet-synchronous electric motor on the basis of the voltage command. The current weakening command calculation unit calculates the current weakening command in which a high-frequency component is amplified on the basis of the difference between the reference voltage value and the output voltage value.

A variable magnetization machine control system comprising a controller configured to adjust a d-axis current waveform and a q-axis current waveform in accordance with an operating condition of a variable magnetization machine to generate an adjusted d-axis current waveform and an adjusted q-axis current waveform that provide a driving voltage to drive the variable magnetization machine at a predetermined speed while maintaining the driving voltage below a predetermined maximum magnitude.