Patent application number | Description | Published |
20080211441 | MOTOR CONTROLLER OF ELECTRIC POWER STEERING DEVICE - 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. | 09-04-2008 |
20080290826 | Motor Controller - A motor controller stores values corresponding to predetermined equivalent resistance which corresponds to power loss generated by switching on and off switching elements. Voltage command values are determined by adding voltage drop values determined from values corresponding to the equivalent resistance and values of current flowing in the switching elements to target applied voltage values corresponding to current command values which correspond to target output of a motor. The switching elements arranged in a power supply line to the motor are switched on and off by control signals generated according to the voltage command values. | 11-27-2008 |
20090078493 | ELECTRIC POWER STEERING SYSTEM - A main power supply and an auxiliary power supply for supplying power to a motor are provided. AMOS-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 V | 03-26-2009 |
20090079373 | MOTOR CONTROLLER AND ELECTRIC POWER STEERING SYSTEM - A current sensor of a motor controller detects the current applied to a motor drive circuit and thus a phase where a failure cannot be detected would occur without taking any measures. However, an abnormal current monitor section contained in a microcomputer receives a voltage signal of an average value of the currents detected in the current sensor by allowing a signal to pass through a first LPF having a cutoff frequency sufficiently lower than the frequency of a PWM signal. Therefore, whether or not the value is within a predetermined normal range is checked, whereby whether or not some failure containing a failure of the current sensor occurs can be easily determined about every phase. | 03-26-2009 |
20090256503 | MOTOR CONTROL APPARATUS AND ELECTRIC POWER STEERING SYSTEM - 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. | 10-15-2009 |
20090260858 | MULTI-LAYER CIRCUIT SUBSTRATE AND MOTOR DRIVE CIRCUIT SUBSTRATE - Conducting layers and resin-made insulating layers are alternately laminated to form a laminated circuit portion, and a metal substrate is installed so as to be in contact with an insulating layer, which is the lowermost layer. The conducting layers, the insulating layers, and the metal substrate are thermal compression bonded. In order to connect the uppermost conducting layer on which electronic component is placed with the lowermost insulating layer, a conducting layer is formed on the inner surface by copper plating to install a heat dissipating via into which a resin is filled. A conducting layer, which is the uppermost layer, is subjected to gold plating, with nickel plating undercoated. An electronic component for driving a motor is placed on the uppermost conducting layer, by which the metal substrate can be used as a motor drive circuit substrate for an electric power steering system. | 10-22-2009 |
20100045217 | Motor control apparatus and electric power steering apparatus - An angle calculation portion of a motor control apparatus determines an angle θ of a rotor, and an angular velocity calculation portion determines an angular velocity ωe 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 ωe, 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. By performing the correction, it is possible to eliminate or suppress a decrease in control accuracy due to a wiring resistance and the like. | 02-25-2010 |
20110290537 | MULTILAYER CIRCUIT SUBSTRATE - 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. | 12-01-2011 |
20120018725 | SEMICONDUCTOR DEVICE FOR DRIVING ELECTRIC MOTOR - 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 | 01-26-2012 |
20130134816 | ROTOR FOR MOTOR AND METHOD FOR MANUFACTURING THE SAME - Non-holding portions of a holding ring are demagnetized by supplying a nonmagnetic element to the non-holding portions while melting the non-holding portions by the application of heat. Each non-holding portion is demagnetized such that, from the melting center toward each melting end portion thereof, the material of the non-holding portion moderately changes from a nonmagnetic material to a ferromagnetic material. The permeability moderately changes, and hence generation of cogging torque during rotation of a rotor is suppressed. | 05-30-2013 |
20130134817 | ROTOR FOR MOTOR AND METHOD OF MANUFACTURING THE SAME - At least part of each bridge portion is heated and molten to form a keyhole, and a nonmagnetic element is disposed around the keyhole. Thus, even when the width of the bridge portion in the radial direction is increased, the bridge portion is demagnetized. Therefore, leakage flux in the bridge portion is reduced, and the output power of a motor is increased. Moreover, by increasing the width of the bridge portion in the radial direction, the strength of the bridge portion is increased, and breakage of the bridge portion due to a centrifugal force at high-speed rotation of a rotor is prevented. | 05-30-2013 |
20130134827 | METHOD FOR MANUFACTURING STATOR FOR MOTOR AND STATOR FOR MOTOR - Teeth coupling portions of a ring-shaped teeth member are demagnetized by supplying a nonmagnetic element to the teeth coupling portions while melting the teeth coupling portion by application of heat. Then, an inner peripheral portion of the ring-shaped teeth member is pressed radially outward. Therefore, it is possible to plastically deform the teeth coupling portions easily, so that the ring-shaped teeth member and a ring-shaped yoke member are easily fitted together. Accordingly, there is provided a method for manufacturing a stator for a motor, in which the amount of leakage flux is reduced and which has favorable magnetic characteristics. | 05-30-2013 |
20130285513 | CONTROL DEVICE AND MOTOR UNIT INCLUDING CONTROL DEVICE - A control device for a motor unit includes: a housing including a bottom wall, a side wall and an accommodation space formed so as to be surrounded by the side wall; a heat sink including a first heat dissipation wall portion upright from the bottom wall in the accommodation space, the first heat dissipation wall portion upright having a first heat dissipation principal surface; a first board portion mounted on the first heat dissipation principal surface and having a first principal surface; and a circuit board including a power element mounted on the first principal surface. | 10-31-2013 |
20140116798 | CONTROL DEVICE AND VEHICLE STEERING SYSTEM INCLUDING CONTROL DEVICE - A circuit board includes control circuit patterns and first drive circuit patterns. A base maintains the circuit board in a state in which the base is opposed to a portion of the circuit board, in which the control circuit patterns are formed, across a space that allows control circuit elements to be mounted at the circuit board. A line module includes second drive circuit patterns electrically connected to the first drive circuit patterns so as to constitute a part of lines of a drive circuit, and is sandwiched between a portion of the circuit board, in which the first drive circuit patterns are formed, and the base. | 05-01-2014 |