Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Hideki Nishino

Yasunori Yamamoto

Hideaki Mori

Shinichi Kuroshima

Taishi Iwanaga

Kiyotaka Tanimoto

Makoto Gotou

Shiro Sakiyama

Takashi Morie

Yoshiaki Igarashi

Kouji Okamoto

Hitoshi Kobayashi

Akira Kawabe

Akio Yokoyama

Masaaki Ochi

Fumiaki Senoue

Taishii Iwanaga

A actuator driver includes a digital filter configured to perform phase compensation of a digital torque command signal using a fed-back digital signal; a digital PWM generator configured to generate a plurality of pulse-width modulated PWM control signals in response to an output of the digital filter; at least one H bridge configured to select and output a first or second terminal voltage in response to the plurality of PWM control signals; first and second continuous time &#x394;&#x3a3; A/D converters configured to convert the first and second terminal voltages from analog to digital, respectively; and a feed-back filter configured to decimate outputs of the first and second continuous time &#x394;&#x3a3; A/D converters to feed back the digital signal to the digital filter.

Actuator driver

A three-phase DC brushless motor and coil winding method provide a coil winding enabling consistent starting with PWM sensorless driving by suppressing the DC offset component of the induced voltage resulting from an imbalance in the motor coil windings. The method of winding the armature winding of the three-phase DC brushless motor renders the difference in mutual inductance substantially zero.

Three-phase DC brushless motor and winding method

A motor driving apparatus has a driver circuit configuration capable of individually adjusting three phase coil currents. Coil current waveforms are formed to have a total of three phase shaft direction forces to be zero in compliance with predetermined mathematical expressions, and thus, three phase coil current profiles can be made independent of one another, and vibration-causing factors attributed to the fact that a certain phase is in an non-energized state are corrected by adjusting the current profiles of the other phases. Consequently, the vibration and the noise can be reduced.

Motor driving apparatus and motor driving method

A PWM control section () gently changes phase currents (Iu, Iv, and Iw) under a current driving control over a pre-drive circuit () and an output circuit (). The pre-drive circuit () suspends energizing of the specific motor coil (Mu, Mv, and Mw) according to a PWM disable signal (NPWM) at PWM disable periods. A self-commutation circuit () performs zero crossing detection according to a BEMF detection signal (DZC) during BEMF detection periods. A count section () selects either a self-commutation signal (SC) or a forced commutation signal (FC) as a commutation signal (CS), whichever enters earlier, and, based on its intervals, generates the PWM disable signal (NPWM) and the BEMF detection signal (DZC). The BEMF detection period starts after the start of the PWM disable period, and finishes together with the PWM disable period at the switching of the energization phases.

Sensorless motor driving device and its driving method

FET power transistors of a power supplying part execute high-frequency switching operation and form current paths to three-phase windings. A voltage detecting part compares terminal voltages of the three-phase windings and produces a detected pulse signal in response to a comparison result. A state shifting part and an activation control part control active periods of the FET power transistors in response to the detected pulse signal. A commanding part produces a command signal in response to an output pulse signal of the voltage detecting means. A switching operation block produces a switching pulse signal in response to a comparison result of a current-detection signal with the command signal, and causes at least an FET power transistor of the power supplying part to perform high-frequency switching in response to the switching pulse signal. The state shifting part produces a timing signal after an adjust time from the detection of the detected pulse signal and shift-holds a holding state in response to the timing signal. The state shifting part changes the adjust time smaller in case that the command signal is larger than a predetermined value, thereby making the product value of the adjust time and the rotational speed smaller in the case.

Motor

Growing community of inventors

Takatsuki, Japan

Hideki Nishino