A data storage device is disclosed comprising a head actuated over a disk, and a spindle motor configured to rotate the disk. A pulse width modulated (PWM) control signal is generated having a frequency based on a PWM clock, the spindle motor is controlled using the PWM control signal, and a frequency of the PWM clock is swung between a minimum frequency and a maximum frequency at a swing rate.

The control method for an electric vehicle sets a motor torque command value based on vehicle information and controls torque of a first motor connected to a first drive wheel which is one of a front drive wheel and a rear drive wheel. The control method for an electric vehicle calculates a first torque command value by a feedforward computation based on the motor torque command value, detects a rotation angular velocity of the first motor, and estimates a rotation angular velocity of the first motor based on the first torque command value by using a vehicle model Gp(s) that simulates a transfer characteristic from a torque input to the first drive wheel to a rotation angular velocity of the first motor.

A thyristor starter is configured to accelerate a synchronous machine from a stop state to a predetermined rotation speed by sequentially performing a first mode of performing commutation of an inverter by intermittently setting DC output current of a converter to zero and a second mode of performing commutation of the inverter by induced voltage of the synchronous machine. The thyristor starter is further configured to raise induced voltage in proportion to the rotation speed of the synchronous machine by keeping field current constant and to suppress rise of the induced voltage by reducing the field current after the induced voltage reaches a first voltage value, in the first mode.

A thyristor starter is configured to accelerate a synchronous machine from a stop state to a predetermined rotation speed by sequentially performing a first mode of performing commutation of an inverter by intermittently setting DC output current of a converter to zero and a second mode of performing commutation of the inverter by induced voltage of the synchronous machine. In a first case in which a first synchronous machine having a first inductance is started, a switching rotation speed for switching from the first mode to the second mode is set to a higher rotation speed, compared with a second case in which a second synchronous machine having a second inductance larger than the first inductance is started.

An apparatus for an alpha trim adjustment includes a phase delay circuit that creates a phase delay for a gate signal for a switching cycle. The gate signal is for a phase of a three-phase, phase shifted alternating current (AC) input of a multi-pulse motor drive powering a direct current (DC) motor. The apparatus includes an alpha trim circuit that modifies the phase delay with an alpha trim adjustment to create an adjusted phase delay for the switching cycle, a delay application circuit that applies the adjusted phase delay to the gate signal.

An apparatus for an alpha trim adjustment includes a phase delay circuit that creates a phase delay for a gate signal for a switching cycle. The gate signal is for a phase of a three-phase, phase shifted alternating current (AC) input of a multi-pulse motor drive powering a direct current (DC) motor. The apparatus includes an alpha trim circuit that modifies the phase delay with an alpha trim adjustment to create an adjusted phase delay for the switching cycle, a delay application circuit that applies the adjusted phase delay to the gate signal.

Provided are an automatic advance angle control system and method for a brushless linear direct current (BLDC) motor. The automatic advance angle control system for the BLDC motor includes a current controller configured to generate an anti-windup output for compensating for accumulated errors of an output voltage provided to the BLDC motor; a voltage headroom calculator configured to generate a voltage headroom from a counter-electromotive force and the output voltage provided to the BLDC motor; and an advance angle controller configured to generate an advance angle for controlling a phase of a phase current of the BLDC motor by performing proportional integration on a difference between the anti-windup output and the voltage headroom when the anti-windup output is generated and configured to ignore the generation of the advance angle when the anti-windup output is not generated.

Provided are an automatic advance angle control system and method for a brushless linear direct current (BLDC) motor. The automatic advance angle control system for the BLDC motor includes a current controller configured to generate an anti-windup output for compensating for accumulated errors of an output voltage provided to the BLDC motor; a voltage headroom calculator configured to generate a voltage headroom from a counter-electromotive force and the output voltage provided to the BLDC motor; and an advance angle controller configured to generate an advance angle for controlling a phase of a phase current of the BLDC motor by performing proportional integration on a difference between the anti-windup output and the voltage headroom when the anti-windup output is generated and configured to ignore the generation of the advance angle when the anti-windup output is not generated.

An apparatus for an alpha trim adjustment includes a phase delay circuit that creates a phase delay for a gate signal for a switching cycle. The gate signal is for a phase of a three-phase, phase shifted alternating current (AC) input of a multi-pulse motor drive powering a direct current (DC) motor. The apparatus includes an alpha trim circuit that modifies the phase delay with an alpha trim adjustment to create an adjusted phase delay for the switching cycle, a delay application circuit that applies the adjusted phase delay to the gate signal.

An apparatus for an alpha trim adjustment includes a phase delay circuit that creates a phase delay for a gate signal for a switching cycle. The gate signal is for a phase of a three-phase, phase shifted alternating current (AC) input of a multi-pulse motor drive powering a direct current (DC) motor. The apparatus includes an alpha trim circuit that modifies the phase delay with an alpha trim adjustment to create an adjusted phase delay for the switching cycle, a delay application circuit that applies the adjusted phase delay to the gate signal.