Abstract: A PWM motor drive device includes: a time counter that counts a time of a polarity of a motor phase signal; a register that retains the time; a zone setting circuit that splits the time into arbitrary zones and generates an arbitrary zone set for which a phase of motor current is adjusted; and a zone correction circuit that compares a motor current phase signal indicating the phase of the motor current with the motor phase signal to correct the zone set.

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 PWM motor drive device includes: a time counter that counts a time of a polarity of a motor phase signal; a register that retains the time; a zone setting circuit that splits the time into arbitrary zones and generates an arbitrary zone set for which a phase of motor current is adjusted; and a zone correction circuit that compares a motor current phase signal indicating the phase of the motor current with the motor phase signal to correct the zone set.

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 zero-crossing detector compares a neutral node voltage of a motor with a back electromotive force of at least one of windings and outputs a first signal every time a zero-crossing is detected as a result of the comparison. A cycle detector detects a cycle of the first signal and outputs a second signal during a final portion of the cycle. A de-energizer de-energizes all the windings of the motor during at least a period of time that the second signal is being output. The zero-crossing detector performs detection of a zero-crossing during the period of time that the second signal is being output.

Abstract: Problems with accuracy reading position detection signal peaks and minute phase differences in the detection current make motor drive control easily susceptible to differences in motor characteristics. The rotor position is determined based on whether or not a terminal difference voltage, which is the difference voltage between the motor terminal voltage and the pseudo-neutral-point voltage when the motor phases are selectively energized, exceeds a specific threshold value. The phase energized to start the motor is determined based on this determination and the motor is energized accordingly to start. Instead of switching directly from the search step at the initial rotor position to the back-EMF voltage mode, a search and start mode that creates initial rotor speed sufficient to start the motor is executed before entering the back-EMF voltage mode.

Abstract: A motor driving apparatus includes a virtual difference voltage detecting unit operable to detect a difference voltage between a virtual neutral point of a resistor circuit connected in parallel to motor coils and a terminal of a motor coil in non-conduction state, a rotor position detecting unit operable to detect a position of the rotor based on the difference voltage, and a controller operable to control commutation of an inverter based on the rotor position. The motor driving apparatus has a searching start mode for detecting the rotor position and energizes the coils, and a back electromotive voltage feedback mode for controlling commutation based on the back electromotive voltage. In the searching start mode, a rotor position searching process and a rotation start torque applying process are alternately performed.

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 includes a neutral point difference voltage detecting unit operable to detect a difference voltage between a virtual neutral point of a resistor circuit connected in parallel to motor coils and an actual neutral point which is a common connection point of the motor coils, a rotor position detecting unit operable to detect a position of the rotor based on the difference voltage, and a controller operable to control commutation of an inverter. A rotation start torque applying process applies a rotation start pulse for providing rotation torque to the rotor based on a determined rotor position.

Abstract: Problems with accuracy reading position detection signal peaks and minute phase differences in the detection current make motor drive control easily susceptible to differences in motor characteristics. The rotor position is determined based on whether or not a neutral point difference voltage, which is the difference voltage between the neutral point voltage and the pseudo-neutral-point voltage when the motor phases are selectively energized, exceeds a specific threshold value. The phase energized to start the motor is determined based on this determination and the motor is energized accordingly to start. Instead of switching directly from the search step at the initial rotor position to the back-EMF voltage mode, a search and start mode that creates initial rotor speed sufficient to start the motor is executed before entering the back-EMF voltage mode.

Abstract: A motor having plural-phase windings and a rotor includes a position detector, a state determining device, an activation controlling device, and a switching controlling device. The position detecting device detects the position of the rotor according to a comparison signal obtained by comparing terminal voltages of the windings in a non-activation phase with a center tap voltage of a common potential of the plural-phase windings and outputting a position detection signal. The state determining device detects the state of the rotor and outputs the result obtained by comparing the position detection signal with a predetermined value.

Abstract: A motor driving apparatus includes a virtual difference voltage detecting unit operable to detect a difference voltage between a virtual neutral point of a resistor circuit connected in parallel to motor coils and a terminal of a motor coil in non-conduction state, a rotor position detecting unit operable to detect a position of the rotor based on the difference voltage, and a controller operable to control commutation of an inverter based on the rotor position. The motor driving apparatus has a searching start mode for detecting the rotor position and energizes the coils, and a back electromotive voltage feedback mode for controlling commutation based on the back electromotive voltage. In the searching start mode, a rotor position searching process and a rotation start torque applying process are alternately performed.

Abstract: A rotor position sensorless multiphase motor driving device includes a rotor; a plurality of phase windings; a common terminal to which one terminal of terminals at both ends of each winding is star connected; an upper-side drive transistor and a lower-side drive transistor connected to the other terminal of the winding; a commutation control unit operable to select two terminals other than the common terminal of the windings, and to turn on the corresponding pair of upper-side drive transistor and the lower-side drive transistor; a rotor position search pulse applying unit operable to apply a search pulse to the selected two terminals; and a comparing unit operable to detect a rotor position based on a response signal generated between the terminal which was unselected and the common terminal according to the search pulse application.

Abstract: A motor driving apparatus includes a neutral point difference voltage detecting unit operable to detect a difference voltage between a virtual neutral point of a resistor circuit connected in parallel to motor coils and an actual neutral point which is a common connection point of the motor coils, a rotor position detecting unit operable to detect a position of the rotor based on the difference voltage, and a controller operable to control commutation of an inverter. A rotation start torque applying process applies a rotation start pulse for providing rotation torque to the rotor based on a determined rotor position.

Abstract: A Motor driving apparatus adjusts activation start timing of high-side activation control signals UU, VU, WU and the low-side activation control signals UL, VL, and WL with a state determination signal SJ in an activation controller 40, in the period from starting to the time when rotor rotating speed reaches a predetermined value, sets the activation start timing earlier than in normal times to perform leading phase activation control, and in normal times when the rotor rotating speed is a predetermined value or more, controls activation start timing in efficient and optimum phase. Hence, the motor driving apparatus can carry out stable PWM sensorless starting without any starting failure such as oscillation, loss of synchronism and reverse rotation and shorten starting time.

Abstract: Problems with accuracy reading position detection signal peaks and minute phase differences in the detection current make motor drive control easily susceptible to differences in motor characteristics. The rotor position is determined based on whether or not a terminal difference voltage, which is the difference voltage between the motor terminal voltage and the pseudo-neutral-point voltage when the motor phases are selectively energized, exceeds a specific threshold value. The phase energized to start the motor is determined based on this determination and the motor is energized accordingly to start. Instead of switching directly from the search step at the initial rotor position to the back-EMF voltage mode, a search and start mode that creates initial rotor speed sufficient to start the motor is executed before entering the back-EMF voltage mode.

Abstract: Problems with accuracy reading position detection signal peaks and minute phase differences in the detection current make motor drive control easily susceptible to differences in motor characteristics. The rotor position is determined based on whether or not a neutral point difference voltage, which is the difference voltage between the neutral point voltage and the pseudo-neutral-point voltage when the motor phases are selectively energized, exceeds a specific threshold value. The phase energized to start the motor is determined based on this determination and the motor is energized accordingly to start. Instead of switching directly from the search step at the initial rotor position to the back-EMF voltage mode, a search and start mode that creates initial rotor speed sufficient to start the motor is executed before entering the back-EMF voltage mode.

Abstract: Problems with accuracy reading position detection signal peaks and minute phase differences in the detection current make motor drive control easily susceptible to differences in motor characteristics. The rotor position is determined based on whether or not a neutral point difference voltage, which is the difference voltage between the neutral point voltage and the pseudo-neutral-point voltage when the motor phases are selectively energized, exceeds a specific threshold value. The phase energized to start the motor is determined based on this determination and the motor is energized accordingly to start. Instead of switching directly from the search step at the initial rotor position to the back-EMF voltage mode, a search and start mode that creates initial rotor speed sufficient to start the motor is executed before entering the back-EMF voltage mode.

Abstract: A rotor position sensorless multiphase motor driving device includes a rotor; a plurality of phase windings; a common terminal to which one terminal of terminals at both ends of each winding is star connected; an upper-side drive transistor and a lower-side drive transistor connected to the other terminal of the winding; a commutation control unit operable to select two terminals other than the common terminal of the windings, and to turn on the corresponding pair of upper-side drive transistor and the lower-side drive transistor; a rotor position search pulse applying unit operable to apply a search pulse to the selected two terminals; and a comparing unit operable to detect a rotor position based on a response signal generated between the terminal which was unselected and the common terminal according to the search pulse application.

Abstract: A motor driving apparatus includes a comparator, a threshold controller, a position determining unit, a phase-switching controller, and a current output unit. While the rotor is stopped, the phase-switching controller supplies a predetermined phase of winding with a current pulse having a predetermined pulse width so as not to cause the rotor to react and operate, in order to determine the initial position of the rotor. The position determining unit determines an initial position of the rotor based on the result of comparison between the induced voltage generated in a non-conduction phase by the current pulse and the threshold. The phase-switching controller performs energization or commutation according to the determined initial position of the rotor to start up the motor.