Patent application number | Description | Published |
20090190903 | MOTOR CONTROLLER AND VEHICULAR STEERING SYSTEM USING SAID MOTOR CONTROLLER - A low speed region position estimating portion is designed to be suitable for when the motor is operating in a low speed region, and estimates a low speed estimated rotational position θ̂ | 07-30-2009 |
20100094505 | Vehicle steering apparatus - A motor is driven based on an axis current value in a rotating coordinate system that rotates in accordance with a control angle that is a rotational angle used in a control. The control angle is calculated by adding an addition angle to an immediately preceding value of the control angle in each predetermined calculation cycle. A command steering torque is set based on a predetermined steering angle-torque characteristic. The addition angle is calculated based on the deviation of a detected steering torque from a command steering torque. The addition angle based on the deviation is changed when a predetermined condition is satisfied. | 04-15-2010 |
20100235049 | Motor control unit and motor control unit for vehicle steering apparatus - A motor control unit controls a motor including a rotor and a stator facing the rotor. A current drive unit drives the motor at an axis current value of a rotating coordinate system that rotates in accordance with a control angle that is a rotational angle used in a control. A control angle calculation unit obtains, at every predetermined calculation cycle, a present value of the control angle by adding an addition angle to an immediately preceding value of the control angle. A torque detection unit detects a torque other than a motor torque and applied to a drive target driven by the motor. A command torque setting unit sets a command torque to be applied to the drive target. An addition angle calculation unit calculates the addition angle to be added to the control angle through a proportional-integral control based on a torque deviation of the torque detected by the torque detection unit from the command torque set by the command torque setting unit. | 09-16-2010 |
20100235051 | MOTOR CONTROL UNIT AND MOTOR CONTROL UNIT FOR VEHICLE STEERING APPARATUS - A motor control unit controls a motor including a rotor and a stator facing the rotor. A current drive unit drives the motor at an axis current value of a rotating coordinate system that rotates in accordance with a control angle that is a rotational angle used in a control. An addition angle calculation unit calculates an addition angle to be added to the control angle. A control angle calculation unit obtains, at every predetermined calculation cycle, a present value of the control angle by adding the addition angle that is calculated by the addition angle calculation unit to an immediately preceding value of the control angle. A torque detection unit detects a torque that is other than a motor torque and that is applied to a drive target driven by the motor. A command torque setting unit sets a command torque to be applied to the drive target. An addition angle correction unit compares the command torque set by the command torque setting unit with the detected torque detected by the torque detection unit, and corrects the addition angle based on a comparison result. | 09-16-2010 |
20110001441 | Motor Control Unit and Vehicle Steering Apparatus - A motor control unit controls a motor including a rotor and a stator facing the rotor. A current drive unit drives the motor at an axis current value of a rotating coordinate system that rotates in accordance with a control angle that is a rotational angle used in a control. An addition angle calculation unit calculates an addition angle to be added to the control angle. A control angle calculation unit obtains, at every predetermined calculation cycle, a present value of the control angle by adding the addition angle that is calculated by the addition angle calculation unit to an immediately preceding value of the control angle. An angular speed calculation unit calculates an angular speed of the rotor. An addition angle correction unit corrects the addition angle based on the angular speed calculated by the angular speed calculation unit. A filtering unit filters the angular speed calculated by the angular speed calculation unit. | 01-06-2011 |
20110118940 | MOTOR CONTROL UNIT AND VEHICLE STEERING SYSTEM - A motor is driven by the γ-axis current of a γδ coordinate system that is an imaginary rotating coordinate system. A command current value preparation unit sets the γ-axis command current value based on the command steering torque and the detected steering torque. The command current value preparation unit includes a command current increase/decrease amount calculation unit and an addition unit. The command current increase/decrease amount calculation unit calculates the current increase/decrease amount for the command current value based on the sign of the command steering torque and the deviation of the detected steering torque from the command steering torque. The current increase/decrease amount calculated by the command current increase/decrease amount calculation unit is added to the immediately preceding value of the command current value by the addition unit. Thus, the command current value in the present calculation cycle is calculated. | 05-19-2011 |
20120055732 | ELECTRIC POWER STEERING SYSTEM - An electric power steering system includes a motor that applies assist force to a steering system, and updates a motor resistance (Rm) that is a value indicating a resistance of the motor. Specifically, the motor resistance (Rm) is updated on the basis of the fact that an induced voltage (EX) of the motor is smaller than a first determination value (GA). In addition, when the induced voltage (EX) is smaller than or equal to a second determination value (GB), a divided value that is obtained by dividing a motor voltage (Vm) by a motor current (Im) is set as a new motor resistance (Rm). | 03-08-2012 |
20120080259 | MOTOR CONTROL DEVICE AND ELECTRIC POWER STEERING APPARATUS - An angular velocity estimate (ωe) used in motor control of an electric power steering is obtained as follows. In a first state period during which the motor substantially stops its rotation, a resistance calculation unit calculates a motor resistance value (Rc) on the basis of a detected value (Vm) of motor voltage and a detected value (Im) of motor current. An average calculation unit obtains an average value (Rav) of the calculated resistance values (Rc) in a retained period. A current-resistance characteristic that associates motor current with motor resistance is held in a characteristic holding unit, and a characteristic updating unit updates the current-resistance characteristic on the basis of the average value (Rav). An estimate calculation unit calculates the angular velocity estimate (ωe) on the basis of the detected value (Vm) of motor voltage, the detected value (Im) of motor current and a motor resistance value (Rm) obtained from the current-resistance characteristic. | 04-05-2012 |
20120158341 | ROTATION ANGLE DETECTION DEVICE - A rotation angle calculation unit calculates a zero-crossing time point when a zero-crossing is detected for an output signal V | 06-21-2012 |
20120182008 | ROTATION ANGLE DETECTING DEVICE - Three magnetic sensors are arranged around a rotor at predetermined angular intervals about the rotation axis of the rotor. Sinusoidal signals that have a phase difference of a predetermined degree of 45° are output from the respective magnetic sensors. A rotation angle computing device detects a magnetic pole transition in a first output signal as follows. Specifically, the rotation angle computing device detects a magnetic pole transition in the first output signal based on a value having a larger absolute value between a current value of the second sinusoidal signal and a current value of the third sinusoidal signal, an immediately preceding value of the first sinusoidal signal and a current value of the first sinusoidal signal. | 07-19-2012 |
20120319680 | ROTATION ANGLE DETECTION DEVICE - Upon detecting a peak value from output signals of one of either a first or a second magnetic sensor, an rotation angle computation device identifies, on basis of an amplitude compensation table corresponding to the one magnetic sensor for which the peak value was detected, a pole number of a magnetic pole sensed by the magnetic sensor. Then, based on the identified pole number and a magnetic pole identification table, a pole number of a magnetic pole sensed by the other magnetic sensor is identified. The pole numbers of the magnetic poles sensed by the respective magnetic sensors are thus identified, and the rotation angle computation device compensates the output signals of the respective magnetic sensors using amplitude compensation gains corresponding to the sensed magnetic poles (magnetic pole pair). | 12-20-2012 |
20130035896 | ROTATION ANGLE DETECTION DEVICE - Angular widths of respective magnetic poles of a detection rotor are stored and divisions are set for respective magnetic pole pairs. Based on output signals from first and second magnetic sensors, a rotation angle computation unit computes first and second rotation angles that are rotation angles within the corresponding division. Based on the angular widths, the rotation angle computation unit identifies the magnetic pole sensed by the first magnetic sensor and computes a first absolute rotation angle using the first rotation angle. Based on the identified magnetic pole and the second rotation angle, the rotation angle computation unit computes a second absolute rotation angle. The rotation angle of the detection rotor is computed based on the first and second absolute angles. | 02-07-2013 |
20130076283 | MOTOR CONTROL UNIT AND MOTOR CONTROL UNIT FOR VEHICLE STEERING APPARATUS - A motor control unit controls a motor including a rotor and a stator facing the rotor. A current drive unit drives the motor at an axis current value of a rotating coordinate system that rotates in accordance with a control angle that is a rotational angle used in a control. An addition angle calculation unit calculates an addition angle to be added to the control angle. A control angle calculation unit obtains, at every predetermined calculation cycle, a present value of the control angle by adding the addition angle that is calculated by the addition angle calculation unit to an immediately preceding value of the control angle. A torque detection unit detects a torque that is other than a motor torque and that is applied to a drive target driven by the motor. A command torque setting unit sets a command torque to be applied to the drive target. An addition angle correction unit compares the command torque set by the command torque setting unit with the detected torque detected by the torque detection unit, and corrects the addition angle based on a comparison result. | 03-28-2013 |