Abstract: A control circuit controls, based on detection values of Hall-effect sensors, an inverter circuit to activate a rotor. After the activation of the rotor, the control circuit controls the rotational speed of the rotor based on the detection value of the Hall-effect sensor. A sensor pin is arranged in a slot between a forward-wound portion and a reverse-wound portion of a U-phase winding. A sensor pin is arranged in a slot between a forward-wound portion and a reverse-wound portion of a V-phase winding. A sensor pin is located on one side in an axial direction with respect to the reverse-wound portion of the U-phase winding. The sensor pins are located respectively at two first positions.

Abstract: A control circuit controls, based on detection values of Hall-effect sensors, an inverter circuit to activate a rotor. After the activation of the rotor, the control circuit controls the rotational speed of the rotor based on the detection value of the Hall-effect sensor. A sensor pin is arranged in a slot between a forward-wound portion and a reverse-wound portion of a U-phase winding. A sensor pin is arranged in a slot between a forward-wound portion and a reverse-wound portion of a V-phase winding. A sensor pin is located on one side in an axial direction with respect to the reverse-wound portion of the U-phase winding. The sensor pins are located respectively at two first positions.

Abstract: Disclosed herein is a motor driver including: a motor current phase detector configured to detect a motor current phase and output a result of the detection as motor current phase information; a motor phase detector configured to detect a motor phase and output a result of the detection as motor phase information; a phase correction value calculator configured to calculate a correction value based on a difference between the motor current phase information and the motor phase information and output a result of the calculation as compensation information; and a motor applied voltage calculator configured to calculate a motor applied voltage representing a voltage to be applied to the motor based on the compensation information and motor phase information received and output a result of the calculation as a phase-compensated motor applied voltage signal.

Abstract: Disclosed herein is a motor driver including: a motor current phase detector configured to detect a motor current phase and output a result of the detection as motor current phase information; a motor phase detector configured to detect a motor phase and output a result of the detection as motor phase information; a phase correction value calculator configured to calculate a correction value based on a difference between the motor current phase information and the motor phase information and output a result of the calculation as compensation information; and a motor applied voltage calculator configured to calculate a motor applied voltage representing a voltage to be applied to the motor based on the compensation information and motor phase information received and output a result of the calculation as a phase-compensated motor applied voltage signal.

Abstract: A sensorless motor drive device has: a first operation mode of generating current waveforms including non-energizing times based on a first rotor position signal generated by detecting zero crossings in windings of a motor as a signal indicating the rotor position of the motor, and supplying currents to the windings of the motor according to the current waveforms; and a second operation mode of generating current waveforms including no non-energizing time based on a second rotor position signal generated without use of zero crossings as the signal indicating the rotor position of the motor, and supplying currents to the windings of the motor according to the current waveforms. The first and second operation modes can be switched to each other.

Abstract: A motor drive unit includes a position detection section configured to detect a rotor position by detecting a zero cross of a counter electromotive voltage during a de-energizing period to output a position detection signal, a current waveform generation section configured to generate, based on a torque command signal and the position detection signal, a current waveform which is to flow through the motor and includes the de-energizing period, an energizing control section configured to generate a control signal for controlling energizing of each of motor coils, and perform switching of an energizing phase of the motor based on the position detection signal, and a drive section configured to supply a current to each of the motor coils according to the control by the energizing control section, and the current waveform generation section changes a start timing of the de-energizing period according to a given control signal.

Abstract: An oscillation frequency selecting section selects any of a first oscillation section and a second oscillation section, depending on whether a signal of a current-passage direction switching section is a forward rotation signal or a brake signal. When the second oscillation section has an oscillation frequency lower than that of the first oscillation section, noise and vibration can be reduced by, for example, selecting the first oscillation section during forward rotation, and the second oscillation section during braking.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A PWM control section (1) gently changes phase currents (Iu, Iv, and Iw) under a current driving control over a pre-drive circuit (2) and an output circuit (3). The pre-drive circuit (2) 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 (5) performs zero crossing detection according to a BEMF detection signal (DZC) during BEMF detection periods. A count section (7) 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.

Abstract: In a PWM-controlled motor driving device, a phase current is prevented from undergoing an abrupt transition at phase current switching points, thereby reducing vibrations and noise of the motor. A PWM control section produces two independent PWM control pulse signals P1 and P2. Two energized phases, which are determined by an energization switching section, are energized with PWM control in parallel according to the PWM control pulse signals P1 and P2. A comparison section compares a current detection signal DS, which indicates the level of the current flowing through a motor coil, with various torque command signals TQ1, TQ2 and TQ3, which are produced by a torque command signal generation section. A masking section masks comparison results CR1 and CR2 as necessary. Thus, an ON period of the PWM control pulse signal P1 and that of the PWM control pulse signal P2 are determined.

Abstract: A motor drive method for a motor driver having output circuits each including upper and lower side switching elements connected in series, and a current detection resistance connected in series with the output circuits in common. The motor drive method includes the steps of: turning ON a switching element on one side of one of the output circuits for a time period corresponding to a predetermined electrical angle; and repeatedly switching switching elements on the other side of a plurality of output circuits among the remaining ones of the output circuits. In the switching step, each of a plurality of periods obtained by dividing the time period corresponding to the predetermined electrical angle includes a first period in which one of the switching elements to be switched is turned ON and a second period in which another one of the switching elements is turned ON.

Abstract: The amplitude expansion circuit as a main part of a drive circuit includes: a VM DC power supply line to which a voltage VM is applied; a VH DC power supply line to which a voltage VH roughly twice as high as the voltage VM is applied; an inverter circuit receiving a pulse signal oscillating between the ground voltage and the voltage VM; another inverter circuit receiving a pulse signal oscillating between the voltage VM and the voltage VH in correspondence with the oscillation of the voltage level of the above pulse signal; a p-channel MOSFET having a gate receiving an output from the inverter circuit; another p-channel MOSFET having a gate connected to the VM DC power supply line; an n-channel MOSFET having a gate connected to the VM DC power supply line; and another n-channel MOSFET having a gate receiving an output from the other inverter circuit. A common connection node of the p-channel MOSFET and the n-channel MOSFET works as the output terminal of the amplitude expansion circuit.

Abstract: A PWM control section (1) gently changes phase currents (Iu, Iv, and Iw) under a current driving control over a pre-drive circuit (2) and an output circuit (3). The pre-drive circuit (2) 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 (5) performs zero crossing detection according to a BEMF detection signal (DZC) during BEMF detection periods. A count section (7) 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.

Abstract: The present invention provides a motor driving device that produces a first PWM control signal and a second PWM control signal according respectively to different torque command signals for energizing motor coils of a plurality of phases with PWM control in parallel, wherein it is possible to avoid a situation where two-phase simultaneous energization continues for a long period of time. For this purpose, a PWM control section unconditionally turns OFF the first and second PWM control signals according to a first reset pulse signal and a second reset pulse signal, respectively, produced by an oscillation section. Thus, it is possible to avoid a situation where two phases are energized simultaneously for a long period of time, and to maintain the parallelism of the two phases being energized.

Abstract: A motor driver having output circuits each including upper and lower side switching elements connected in series. The motor driver includes: a current detection resistance connected in series with the output circuits in common; a phase switch circuit for turning ON a switching element on one side of one of the output circuits for a time period corresponding to a predetermined electrical angle and switching switching elements on the other side of a plurality of output circuits among the remaining ones of the output circuits; and an ON-period control section for generating a signal for controlling the switching operation so that each of periods obtained by dividing the time period includes a first period in which a plurality of switching elements are turned ON and a second period in which one of the switching elements turned ON in the first period is kept ON.

Abstract: A motor drive method for a motor driver having output circuits each including upper and lower side switching elements connected in series, and a current detection resistance connected in series with the output circuits in common. The motor drive method includes the steps of: turning ON a switching element on one side of one of the output circuits for a time period corresponding to a predetermined electrical angle; and repeatedly switching switching elements on the other side of a plurality of output circuits among the remaining ones of the output circuits. In the switching step, each of a plurality of periods obtained by dividing the time period corresponding to the predetermined electrical angle includes a first period in which one of the switching elements to be switched is turned ON and a second period in which another one of the switching elements is turned ON.

Abstract: The amplitude expansion circuit as a main part of a drive circuit includes: a VM DC power supply line to which a voltage VM is applied; a VH DC power supply line to which a voltage VH roughly twice as high as the voltage VM is applied; an inverter circuit receiving a pulse signal oscillating between the ground voltage and the voltage VM; another inverter circuit receiving a pulse signal oscillating between the voltage VM and the voltage VH in correspondence with the oscillation of the voltage level of the above pulse signal; a p-channel MOSFET having a gate receiving an output from the inverter circuit; another p-channel MOSFET having a gate connected to the VM DC power supply line; an n-channel MOSFET having a gate connected to the VM DC power supply line; and another n-channel MOSFET having a gate receiving an output from the other inverter circuit. A common connection node of the p-channel MOSFET and the n-channel MOSFET works as the output terminal of the amplitude expansion circuit.

Abstract: The present invention provides a motor driving device that produces a first PWM control signal and a second PWM control signal according respectively to different torque command signals for energizing motor coils of a plurality of phases with PWM control in parallel, wherein it is possible to avoid a situation where two-phase simultaneous energization continues for a long period of time. For this purpose, a PWM control section unconditionally turns OFF the first and second PWM control signals according to a first reset pulse signal and a second reset pulse signal, respectively, produced by an oscillation section. Thus, it is possible to avoid a situation where two phases are energized simultaneously for a long period of time, and to maintain the parallelism of the two phases being energized.