Abstract: In an electric power steering apparatus including a charge-discharge circuit 16 that selectively configures a first output mode in which only a main power supply including a battery 9 is used to supply an electric power to a motor 4 or a second output mode in which the main power supply and an auxiliary power supply 14 are used to supply the electric power to the motor 4, and a control circuit 6 that selects the output mode of the charge-discharge circuit 16 according to the electric power required for steering assist, the control circuit 6 selects the second output mode when the electric power required for steering assist in the first output mode becomes equal to or higher than an upward threshold value P1 or selects the first output mode when the electric power required for steering assist in the second output mode becomes equal to or lower than a downward threshold value P2 that is lower than the upward threshold value P1.

Abstract: When a source consisting of series-connected battery 7 and auxiliary power supply 9 supplies an electric power to a motor 4, a MOS-FET 13 for preventing a current induced by a voltage of the auxiliary power supply 9 from being reversed upstream should be off if it operates normally. Therefore, voltages at the opposite terminals of the MOS-FET 13 should have a difference which corresponds to a voltage of the auxiliary power supply 9. Hence, the voltages at the opposite terminals of the MOS-FET 13 are detected by two voltage detectors 23 and 25 when the electric power from the auxiliary power supply 9 is supplied to the motor 4. If the potential difference between the voltages at the opposite terminals of the MOS-FET 13 is equal to or less than a predetermined value, a control circuit 24 issues a failure signal upon determination that the MOS-FET 13 suffers a short-circuit fault. A MOS-FET 15 is also monitored in the same way.

Abstract: An angle calculation portion of a motor control apparatus determines an angle ? of a rotor, and an angular velocity calculation portion determines an angular velocity ?e of the rotor. A command current calculation portion determines command currents id* and iq* on dq axes, based on a steering torque T and a vehicle speed S. An open-loop control portion determines command voltages vd and vq on the dq axes based on the command currents id* and iq* and the angular velocity ?e, according to circuit equations of a motor. A dq-axis/three-phase conversion portion converts the command voltages vd and vq to command voltages of three phases. A three-phase voltage correction portion corrects the command voltage so that an actual time average value of a voltage applied to each phase is equal to a time average value of a voltage that is to be applied to the phase if the voltage is not decreased, in order to compensate for a decrease in the applied voltage.

Abstract: An electric power steering apparatus includes a charge-discharge circuit including a circuit charging an auxiliary power supply by turning on and off an MOS-FET for voltage boosting and that selectively configures a first output mode in which an electric power is supplied to a motor by a first electrical conduction path to which a voltage of a battery is applied or a second output mode in which the electric power is supplied to the motor by a second electrical conduction path to which a voltage of a source of the series-connected battery and auxiliary power supply is applied. When a failure of the battery is detected, the electric power steering apparatus connects the first conduction path to an electrical conduction path to ground by continuously holding the MOS-FET in an on-state and drives the charge-discharge circuit to select the second output mode, thereby configuring a circuit to supply the motor with the electric power only from the auxiliary power supply.

Abstract: If the magnitude of a command voltage vector is greater than a predetermined voltage value indicated by a voltage limit circle, the magnitude of a voltage vector, which corresponds to a q-axis current and which forms the command voltage vector, is adjusted so that the magnitude of the command voltage vector is equal to or less than the predetermined voltage value. Then a q-axis current estimated value is obtained based on i) the ratio of the magnitude of the voltage vector from the q-axis current after adjustment to the magnitude of the voltage vector from the q-axis current before adjustment, and ii) a q-axis current command value.

Abstract: A FET for driving an electric motor includes a source electrode. The source electrode has main electrode surfaces to which bonding wires, through which a drive current for an electric motor passes, are joined, and inspection electrode surfaces that are arranged so as to be independent of and apart from the main electrode surfaces. The inspection electrode surfaces are provided so as to contact a probe of an inspection device that performs an inspection of the FET 3.

Abstract: A multilayer circuit substrate includes a substrate body in turn including a plurality of conductor layers and a plurality of insulating layers that are laminated alternately. The plurality of conductor layers include an uppermost conductor layer that includes a plurality of conductor patterns and a lowermost conductor layer that includes a plurality of conductor patterns. A plurality of semiconductor devices is respectively mounted on the plurality of conductor patterns of the uppermost conductor layer. The plurality of conductor patterns of the lowermost conductor layer includes a plurality of heat releasing patterns. The plurality of heat releasing patterns is respectively provided in one-to-one correspondence with the plurality of semiconductor devices. Each of the heat releasing patterns has an area no less than an area of the corresponding semiconductor device. Each of the heat releasing patterns is connected to the corresponding semiconductor device via a corresponding heat releasing via.

Abstract: An electric power steering system in which a current command for a brushless DC motor is determined based on a detected steering torque, a voltage to be applied is determined based on a difference between the current command value and a current value flowing to the motor, and steering assist is implemented by applying the voltage so determined to the motor. A rotational angular velocity is computed based on a detected rotor position, and it is determined that the motor is abnormal when a rotational angular velocity determination unit determines that the rotational angular velocity is equal to or less than a predetermined value, a current command value determination unit determines that the current command value is equal to or less than a predetermined value, and a voltage determination unit determines that the voltage applied to the motor falls out of a predetermined voltage range.

Abstract: When stopping operation of an electric power steering apparatus, a motor relay is kept in an on-state even after a power supply relay is in an off-state. A drive control portion sets a target value of a d-axis current to a value other than zero and sets a target value of a q-axis current to zero, and performs a processing same as that at the time of rotating a motor. MOS-FETs contained in a motor driving circuit are controlled such that each of driving currents of the two phases or more is not zero and the brushless motor does not rotate even supplied with these driving currents. Electric charge accumulated in a capacitor is discharged via the MOS-FETs each in an on-state, a motor relay and the windings of the brushless motor. The electric charge accumulated in the capacitor may be discharged via the excitation coil of the motor relay.

Abstract: A main power supply and an auxiliary power supply for supplying power to a motor are provided. A MOS-FET for supplying power from the main power supply and a MOS-FET for supplying power from the main and auxiliary power supplies are provided. When a phenomenon in which a rotor of a motor is rotated by the going-back force of steered wheels occurs, and voltage VG of power generated by the motor satisfies the relation VG>VB+VC where VB is a voltage of the main power supply and VC is a voltage of the auxiliary power supply, a control circuit and a gate drive circuit turn off both MOS-FETs so as to charge the auxiliary power supply using the voltage VG through a parasitic diode of the MOS-FET.

Abstract: In a motor controller, a current detection unit detects an electric current flowing through a brushless motor. An open loop control unit determines a command value indicating a level of a command voltage in accordance with a motor circuit equation, based on a command current value indicating an amount of electric current to be supplied to the brushless motor and an angular velocity of a rotor in the brushless motor. A correction unit calculates a correction value based on a difference between the command current value and a current value detected by the current detection unit when the electric current is detected by the current detection unit and corrects the command value according to the correction value, and corrects the command value according to the correction value even when an electric current is not detected by the current detection unit.

Abstract: An angle computing section determines an angle of a rotor, and an angular velocity computing section determines angular velocity of the rotor. A command current computing section determines, from a steering torque and vehicle velocity, command currents and taken along d-q axes. An open loop control section determines, from command currents and angular velocity, command voltages taken along the d-q axes in accordance with motor circuit equations. A d-q axis/three-phase conversion section converts the command voltages into command voltages of three phases. A ? computing section determines the number of armature winding flux linkages included in a motor circuit equation from a q-axis command voltage, the current value detected by a current sensor, and the angular velocity. Circuit resistance including armature winding resistance R included in the motor circuit equation may also be determined by means of the same configuration.

Abstract: A command current setting portion has a target value corrector that calculates d-axis and q-axis current command values idc, iqc that are to be supplied to an open-loop controller, based on d-axis and q-axis current target values id*, iq*. When d-axis and q-axis voltage target value vd*, vq* calculated from the d-axis and q-axis current target values id*, iq* by the motor circuit equations exceed a voltage limit, this target value corrector 26 corrects the d-axis and q-axis current target values id*, iq* by the field weakening control such that d-axis and q-axis voltages vd, vq and d-axis and q-axis currents id, iq satisfy ?(vd2+vq2)?Vlim and ?(id2+iq2)?Ilim respectively. The d-axis and q-axis current command values idc, iqc are obtained by this correction.

Abstract: In a motor controller which supplies electric power to a motor of an electric power steering device from a main power supply and an auxiliary power supply, an N-channel MOS-FET is connected in parallel with a diode which is provided to prevent a sneak current from the auxiliary power supply to the main power supply. When electric power is supplied to the motor from the main power supply, the MOS-FET is turned on. Then, most of currents flow into the MOS-FET such that a power loss is reduced and a reduction in efficiency is prevented. The MOS-FET has high speed responsibility and excellent durability.

Abstract: A motor control device of the present invention includes: target electric current value setting units (15 and 16) that set target electric current values that should be supplied to a motor (1), basic voltage value computing units (511, 521, 51a, and 52a) that compute basic voltage values for driving the motor, a rotation angle speed computing unit (23) that computes a rotation angle speed of the motor, correction value computing units (50, 512, 515, 516, 522, 525, and 526) that compute correction values for correcting the basic voltage values based on motor electric current values and a rotation angle speed of the motor, correcting units (513 and 523) that obtain voltage command values by correcting the basic voltage values by the correction values computed by the correction value computing units, and a driving unit (13) that drives the motor by using voltage command values.

Abstract: An angle calculator detects a rotation angle ?a of a rotor. A three-phase/d-q axis converter outputs detected current id, iq on d-q coordinate axes by making a conversion, based on a corrected detection angle ?c obtained by adding or subtracting an amount of detection deviation from a time point of current detection to or from the detection angle ?a. A command current calculator calculates command current id*, iq* on the d-q coordinate axes based on a steering torque T and a speed S. A feedback controller calculates command voltages vd, vq on the d-q coordinate axes based on the command current id*, iq* and the detected current id, iq. A d-q axis/three-phase converter converts the command voltages vd, vq into three-phase command voltages, based on a corrected detection angle ?b obtained by adding an amount of detection deviation from a time point when a motor is driven to the detection angle ?a. The deviation can be eliminated by the command voltages, and the motor can be driven with high precision.

Abstract: Disclosed is a vehicle steering apparatus (1; 301) equipped with a control device (12; 322) which controls the actuation of an electric motor (18; 317). First and second housings (23, 24 325, 312), which are in contact with each other, partition off an accommodation chamber (100; 324) which contains the control device (12; 322). The first housing (23; 325) is at least one part of the motor housing (25; 323). The first housing (23; 325) includes a first interior wall surface (101; 401) which partially partitions the accommodation chamber (100; 324). The second housing (24; 312) includes a second interior wall surface (102; 402) which partially partitions the accommodation chamber (100; 324). The first and the second interior wall surfaces (101, 102; 401, 402) are opposite each other with respect to the axial direction (X1) of a rotatable shaft (37; 352) of an electric motor (18; 317).

Abstract: A motor control device comprising a control board for controlling driving of an electric motor, the control board including a multilayer circuit board having inner layers and outer layers, a ground pattern disposed around an output shaft of the electric motor formed on one of the inner layers, and a severed portion formed on a part of the ground pattern, so as to sever through the ground pattern in a radial direction of the output shaft. The construction reduces noise from the motor control device.

Abstract: An electric power steering apparatus (1) comprises a control device (12), which controls driving of an electric motor (18) based on the detection signals from a rotational position-detecting sensor (72; 72A), which detects the rotational position of the rotor (64) of the electric motor (18), and a steering status detecting sensor (11; 11A). The control device (12) is housed in a housing (100) that is partitioned by a first housing (23), which is at least a portion of the motor housing (25) for the electric motor (18), and a second housing (24; 24A; 24B) that touches the first housing (23). At least one of the rotational position-detecting sensor (72; 72A) and steering state detecting sensor (11; 11A) is connected to the control device (12) by means of only a signal wire (81; 134) inside the first housing (23) or the second housing (24; 24A; 24B).

Abstract: When stopping operation of an electric power steering apparatus, a motor relay is kept in an on-state even after a power supply relay is in an off-state. A drive control portion sets a target value of a d-axis current to a value other than zero and sets a target value of a q-axis current to zero, and performs a processing same as that at the time of rotating a motor. MOS-FETs contained in a motor driving circuit are controlled such that each of driving currents of the two phases or more is not zero and the brushless motor does not rotate even supplied with these driving currents. Electric charge accumulated in a capacitor is discharged via the MOS-FETs each in an on-state, a motor relay and the windings of the brushless motor. The electric charge accumulated in the capacitor may be discharged via the excitation coil of the motor relay.