Nippon Soken, Inc.

Toyota Jidosha Kabushiki Kaisha

Denso Corporation

Nippondenso Co., Ltd.

Hiroyuki Sakakibara

Hiroya Tsuji

Shinji Ichikawa

Kazuyoshi Obayashi

Tomoya Okuno

Yoshiyuki Kago

Naoyoshi Takamatsu

Shigeyuki Akita

Yuji Hayashi

Yoshio Shinoda

Masao Kodera

Satoshi Hirose

Yasuhisa Yoshino

Hiromichi Kuno

Tsuyoshi Maeno

Kazuki Fukatsu

Takumi Inoue

Takashi Sumi

In an electrical power converter, an input circuit performs switching for converting a supply voltage of a power source to alternating-polarity voltage pulses which are applied to the primary winding of a transformer. Each voltage pulse is controlled (e.g., pulse width or amplitude is adjusted) based on a detected value of current flow in the primary winding, where the value has been detected an even-numbered plurality of voltage pulses previously. Any DC component of current flow in the primary winding, caused by manufacturing deviations between switching elements in the input circuit, can thereby be suppressed, and DC flux bias in the transformer thereby suppressed.

Power converter enabling suppression of magnetic flux bias in a transformer of the converter

A voltage detector for detecting a voltage generated in a second resonant coil that is disposed to face a first resonant coil and that performs at least one of electric power transmission and electric power reception to and from the first resonant coil in a contactless manner by means of electromagnetic resonance includes: a first high-impedance element having one end connected to one end of the second resonant coil; a second high-impedance element having one end connected to the other end of the second resonant coil; a low-impedance element connected between the other end of the first high-impedance element and the other end of the second high-impedance element and having an impedance smaller than each of those of the first and second high-impedance elements; and an output terminal for outputting a signal associated with a voltage applied across the low-impedance element.

Voltage detector, malfunction detecting device, contactless power transmitting device, contactless power receiving device, and vehicle

A coil unit performs at least one of transmission and reception of electric power using electromagnetic resonance between the coil unit and a primary resonance coil disposed to face the coil unit. The coil unit includes a secondary resonance coil that includes a plurality of coils, and that electromagnetically resonates with the primary resonance coil. A first coil among the plurality of coils is disposed in a manner such that a magnetic field generated by the first coil has a phase opposite to a phase of a magnetic field generated by at least one coil other than the first coil among the plurality of coils, with respect to a plane that faces the primary resonance coil.

Coil unit, non-contact power transmission device, non-contact power reception device, non-contact power supply system, and vehicle

Electric power supplying equipment and an electric power receiving device include a primary self resonant coil and a secondary self resonant coil, respectively, resonating through an electromagnetic field to allow the electric power supplying equipment to supply the electric power receiving device with electric power in a non-contact manner. A control device controls a high frequency electric power supply device to control supplying electric power from the primary self resonant coil to the secondary self resonant coil. The control device estimates a distance between the primary self resonant coil and the secondary self resonant coil from an S-parameter S11 varying with the distance between the primary self resonant coil and the secondary self resonant coil, and controls supplying electric power, based on that estimated distance.

Non-contact electric power supplying equipment, non-contact electric power receiving device, and non-contact electric power supplying system

A surge voltage target setting unit obtains a main circuit power supply voltage of a semiconductor power conversion device based on an inter-terminal voltage of a semiconductor switching element detected by a voltage detection unit, and sets a control target of a surge voltage in accordance with the obtained main circuit power supply voltage. An active gate control unit, when the semiconductor switching element is turned off, sets a quantity of voltage modification so as to modify a gate voltage in a direction raising the gate voltage, that is, in a direction lowering a turn-off speed, based on feedback of the inter-terminal voltage, when the inter-terminal voltage exceeds the control target.

Semiconductor power conversion device

A permanent magnet synchronous motor having multiple-phase armature windings and a rotor is subjected to sensor-less control. Phase voltages are generated in response to voltage command values. The generated phase voltages are applied to the armature windings. Phase currents through the armature windings are detected. The detected phase currents depend on the voltage command values. An angular position and an angular velocity of the rotor are calculated from the detected phase currents. The voltage command values are adjusted in response to the calculated angular position and the calculated angular velocity of the rotor to implement feedback control of the motor. An angular velocity of the rotor is estimated from a time-domain variation in the calculated angular position of the rotor. A determination is made as to whether or not the calculated angular velocity of the rotor and the estimated angular velocity of the rotor are substantially equal to each other. The calculated angular position of the rotor is changed by a predetermined phase value and is thereby corrected when it is determined that the calculated angular velocity of the rotor and the estimated angular velocity of the rotor are not substantially equal to each other.

Method and apparatus for sensor-less control of permanent magnet

If the magnitude of a voltage command vector to a motor driver is smaller than a preset value in a control period, in each of a predetermined number of subsequent control periods (a compensation period), a pulse voltage vector is added to the voltage command vector so as to make substantially zero the average value of the added pulse voltage vectors during the compensation periods, and the compensated voltage command vector is used for the subsequent calculation. Also, two direction data for each phase winding are stored at the center of each of the two dead times following the edges of a voltage command pulse in each control period. An estimated phase voltage is calculated from the last voltage command pulse width, a phase voltage fluctuation during the two dead time of each control period and the stored direction data. The rotor position angle is precisely calculated from the estimated phase voltage.

Sensorless control system and method of permanent magnet synchronous

A sensor-less control apparatus is designed for a permanent magnet synchronous motor having multiple-phase armature windings and a rotor. The sensor-less control apparatus includes a first device for calculating a rotational angle and an angular velocity of the rotor from phase currents and phase voltages of the armature windings. A second device is operative for controlling energizations of the armature windings in response to the rotational angle and the angular velocity calculated by the first device. A third device is operative for correcting the rotational angle calculated by the first device into a correction-resultant rotational angle and informing the second device of the correction-resultant rotational angle, and for feeding back information of the correction-resultant rotational angle to the first device. A fourth device contained in the third device is operative for low-pass-filtering the rotational angle calculated by the first device and changing the rotational angle into a filtering-resultant rotational angle. A fifth device contained in the third device for, in cases where a previous rotational angle outputted from the fourth device and the rotational angle calculated by the first device are not in a same period, correcting the previous rotational angle into a correction-resultant previous rotational angle and informing the fourth device of the correction-resultant previous rotational angle.

Sensor-less control apparatus for permanent magnet synchronous motor

A speed control system for a motor vehicle automatically controls a throttle valve so as to allow the vehicle to run at a desired velocity at all times. The system includes a laser radar for detecting a preceding vehicle and measuring the distance therefrom, and a control computer in which a proper distance responsive to a vehicle velocity is set. The control computer discriminates proximity to the preceding vehicle through change in the distance at a certain interval. When the distance exceeds the proper distance, the control computer reduces the desired velocity in case proximity to the preceding vehicle is discriminated at a plurality of times continuously and increases the desired velocity in case no such proximity is discriminated, and when the distance is below the proper distance, the computer decelerates the vehicle by directly controlling the throttle valve in the closing direction, allowing tracing running with the proper distance from the preceding vehicle.

Speed control system for a motor vehicle

A vehicle speedometer is disclosed which accurately measures vehicle velocity despite significant vehicle vibration, which causes variation of the angle of incidence of the measuring wave. Two transceivers are mounted on the vehicle, along with means to determine a frequency difference and an angle variation, both being used in an accurate velocity determination.

Vehicle speedometer

An apparatus for detecting obstructions behind a vehicle, employing ultrasonic waves is disclosed. The apparatus comprises an ultrasonic transmitting and receiving device disposed on the rear portion of the vehicle, an electric motor for rotating the transmitting and receiving device at a constant velocity, an angle sensor for detecting the rotating angle of the transmitting and receiving device and a sonar circuit for emitting ultrasonic waves through the transmitting and receiving device at predetermined rotating angles, receiving ultrasonic waves reflected from obstructions through the transmitting and receiving device at predetermined rotating angles and measuring the distance to the obstructions from the time taken from the transmission to the reception of the ultrasonic waves. According to the apparatus of the present invention, the distances to obstructions in every region behind the vehicle can be accurately and easily measured by rotating a single transmitting and receiving device by means of the electric motor at a constant velocity.

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Hekinan, Japan

Hiroyuki Sakakibara