Jtekt Corporation

Hiroshi Kitamoto

Toshiki Kumeno

Akihiro Takeuchi

Riku Nagayama

Goro Tsuji

Chishin Yohena

Nobuaki Ikehara

Nobuyuki Togashi

Toshihiro Ishikawa

Hiroshi Sumasu

Nobuhiro Uchida

Wheelchair

A first PWM count computation unit computes a first PWM count for each of three phases in a first system. A second PWM count computation unit computes a second PWM count for each of three phases in a second system. Upper and lower switching elements for each phase in the first system are controlled in accordance with a first pattern in which the upper and lower switching elements are varied in the order of an upper on state, a lower on state, and the upper on state from the time of start of PWM cycles. Upper and lower switching elements for each phase in the second system are controlled in accordance with a second pattern in which the upper and lower switching elements are varied in the order of a lower on state, an upper on state, and the lower on state from the time of start of PWM cycles.

Motor control device

An overcurrent protection circuit includes an amplifier configured to amplify an inter-terminal voltage of a shunt resistor, an offset application circuit configured to allow the amplifier to provide an output with a predetermined offset voltage additionally applied thereto, a first comparator that compares an output voltage from the amplifier with a predetermined first reference voltage higher than the offset voltage to output a through-current sensing signal when the output voltage from the amplifier is higher than a first reference voltage, and an amplifier failure determination circuit that compares the output voltage from the amplifier with a predetermined second reference voltage that is higher than zero and lower than the offset voltage to output an amplification circuit failure determination signal corresponding to a result of the comparison.

Overcurrent protection circuit

In an electric power converter, a driver unit includes an output unit, an auxiliary power source, a switch circuit unit, and a diode. The output unit includes first and second MISFETs and selectively outputs an on signal or an off signal to a gate electrode of a first HEMT. The auxiliary power source outputs a predetermined positive voltage. The switch circuit unit selectively connects a source electrode of the first MISFET to the auxiliary power source or a drain electrode of the first HEMT. The diode is connected to a source electrode of the second MISFET and is oriented such that forward current flows to a source electrode of the first HEMT. In the event of a short circuit in a certain HEMT, a microcomputer connects the source electrode of the first MISFET to the auxiliary power source and outputs an off command to the driver unit.

Electric power converter

In an electric power steering system, an offset correction value setting unit corrects second offset correction values in a state where 100% of current command values is distributed to a first control unit, and 0% of the current command values is distributed to a second control unit. The offset correction value setting unit corrects first offset correction values in a state where 100% of the current command values is distributed to the second control unit, and 0% of the current command values is distributed to the first control unit.

Electric power steering system

An inverter includes a positive electrode terminal and a negative electrode terminal, upper-arm switching elements and lower-arm switching elements, and a voltage divider that supplies partial voltages of a voltage between the positive electrode terminal and the negative electrode terminal to a gate and a drain, respectively, of the lower-arm switching element. The lower-arm switching element includes an HEMT. In the voltage divider, the partial voltages are set to turn the lower-arm switching element off when a positive electrode and a negative electrode of a DC power supply are reversely connected to the positive electrode terminal and the negative electrode terminal, respectively.

Inverter, motor control apparatus, and power steering system

A motor control apparatus includes an inverter, a driver, a negative voltage circuit, a voltage dividing circuit, and a detection unit. The inverter includes an upper-arm switching element and a lower-arm switching element to supply a voltage of a node between the upper-arm switching element and the lower-arm switching element to a motor as a phase voltage. The driver applies a first voltage or a second voltage to the upper-arm switching element to control and turn the upper-arm switching element on and off. The negative voltage circuit supplies a voltage lower than the voltage of the node to the driver as the second voltage. The voltage dividing circuit performs voltage division between the negative voltage circuit and a negative power supply. The detection unit outputs a signal based on a voltage resulting from the voltage division by the voltage dividing circuit.

Motor control apparatus and power steering system

In an abnormality detection system for a rotation angle sensor, a fact that an abnormality has occurred in one of sine signals (S, S) or in one of cosine signals (S, S) is detected based on a sum of the electrical signals (S, S), and a sum of the electrical signals (S, S) (first detection result). A fact that an abnormality has occurred in one of the positive sine and cosine signals (S, S) or in one of the negative sine and cosine signals (S, S) by comparing a first temperature computed using a correlation between an amplitude and a temperature and based on the electrical signals (S, S), a second temperature computed using a correlation between the amplitude and a temperature and based on the electrical signals (S, S), and a third temperature detected by a temperature sensor with each other (second detection result). A microcomputer identifies which of the electrical signals is abnormal by comparing the first and second detection results with each other.

Abnormality detection system for rotation angle sensor

A motor rotation angle sensor includes a plurality of Hall elements and a plurality of switches, each a which is able to interrupt supply of power for operating a corresponding one of these Hall elements.

Displacement detection device, vehicle steering system, and motor

The electrical power steering apparatusincludes the 1MOS-FETand the 2MOS-FETaccommodating the 1parasitic diodeand the 2parasitic diodein the conducting path between the batteryand the motor driving circuitand being connected in series at the opposite direction respectively, and the condenserin an output side of the latter 2MOS-FET. The ECUof the controller of the electrical power steering apparatus controls to turn on or off the 1MOS-FETand the 2MOS-FETin accordance with the predetermined sequence after the ignition switchis turned on, detecting the fault of the 1MOS-FET, the 2MOS-FETand the 1parasitic diodeand the 2parasitic diodeon the basis of the output voltage from each of the 1MOS-FETand the 2MOS-FET

Controller for electrical power steering apparatus

In a motor control device that is used for, for example, an electric power steering system or another vehicle steering system equipped with a motor, a relay circuit () that serves as a power supply breaker is provided in a power feed line (Lp) of a pre-driver () of a circuit that is a component of the motor control device. The operation of the relay circuit () is controlled by a relay signal (S_rly) output from a microcomputer ().

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Toyota, Japan

Hiroshi Kitamoto