Hitachi Astemo Ltd.

Hitachi Automotive Systems, Ltd.

Hitachi, Ltd.

Renesas Electronics Corporation

Tomohiko Yano

Shinichirou Wada

Yoichiro Kobayashi

Hiroki Yamashita

Taizo Yamawaki

Hideyuki Sakamoto

Takashi Oshima

Mitsuhiko Watanabe

Hiroshi Shinoda

Hideyuki Nagaishi

Takashi Kawamoto

Atsushi Arata

Mitsuya Fukazawa

Tetsuo Matsui

Kenichi Hoshino

Ryusuke Sahara

Provided is a power conversion device capable of observing a chip temperature with high accuracy without increasing a cost of the power conversion device mounted with a current sense element for observing a main current of a power device. A main control MOSFET, a current MOSFET, and a diodeconnected to a source electrodeof the main control MOSFETand a source electrodeof the current MOSFETare mounted in a chip of a power device, a temperature measurement circuitis connected to the source electrodeof the current MOSFET, and when the main control MOSFETis in an off state, a forward current (I) is caused to flow through the diode, and an anode potential is observed to measure the chip temperature.

Power conversion device configured to observe chip temperature

A power conversion apparatus accurately estimates a main current of a power device using observation of a sense current. The power conversion apparatus includes: an inverter circuit including a device having a main element and a sense element; a temporary-main-current estimator estimates a current flowing through the main element, from a sense current flowing through the sense element, as a temporary main current; a temperature-difference estimator configured to estimate a temperature difference between the main element and the sense element based on a gate drive signal for the main element and the temporary main current; a main-current corrector corrects the temporary main current using the estimated temperature difference and a temperature characteristic of on-resistance of the main element and output the corrected temporary main current as a corrected main current; and an inverter control circuit configured to output the gate drive signal based on the corrected main current.

Power conversion apparatus

Provided is a novel power conversion device that enables estimation of a temperature of a power device without using a temperature sensing diode and can accurately estimate a temperature and a current of a current sensing element that observes a main current. A measurement voltage (Vref) is applied between source terminals (and) of a main control elementand a current sensing elementin a state in which the main control elementand the current sensing elementare turned off, and a temperature of a power deviceis estimated from a current (Ib) flowing between the source terminals (and) of the main control elementand the current sensing elementat the time of the application by using the fact that a resistance value of a semiconductor substrate between the source terminals of the main control elementand the current sensing elementhas temperature dependency.

Power conversion device

There is a problem that an area of a principal current cell is reduced by an area of a bonding pad wiring layer for a sub-cell. A source electrodeof a current detection cellis electrically connected to a bonding pad wiring layerformed on an interlayer insulating filmvia a wiring layer contact. The bonding pad wiring layeris formed with respect to a source electrodeof a principal current cellso as to cover a part of the source electrodevia the interlayer insulating film. As a result, the source electrodeis miniaturized, and a size of the source electrodeis made substantially equal to a size of the current detection cell. Therefore, the current detection celland the principal current cellare disposed close to each other.

Semiconductor device including sub-cell disposed at chip center

An electric field measuring device measures an electric field corresponding to an inter-electrode voltage between two electrodes, based on a voltage signal that arises at an electric field antenna including the two electrodes because of the electric field. The electric field measuring device includes an amplifier, a reference capacitive element, a GPIO that generates a step wave, and a microcomputer that processes a voltage signal. The microcomputer inputs the step wave to the amplifier, using the GPIO, obtains a step response waveform, and obtains an amplitude compensation factor, based on the step response waveform. The microcomputer compensates the voltage signal, using the amplitude compensation factor.

Electric field measuring device and electric field measuring method

A leakage voltage detection system can be easily mounted on a ground structure such as an existing street light or a traffic light and can detect a leakage voltage of an electric structure in real time. The leakage voltage detection system includes a sensor node mounted on a ground structure, and an equipment management server that determines a risk of a leakage voltage in the ground structure based on detection voltage information from the sensor node. The sensor node includes an electric field probe that measures a potential difference caused by an electric field detected by electrodes, and a sensor box that detects the potential difference between the electrodes of the electric field probe and transmits the potential difference to the equipment management server as a detection voltage. The equipment management server determines the risk of the leakage voltage where the sensor node is mounted based on the received detection voltage from the sensor node, and outputs information on determination of the risk of the leakage voltage.

Leakage voltage detection system and leakage voltage detection method

A transient increase or decrease of power supplied to a reconfiguration circuit to be a logic circuit whose circuit configuration can be changed is reduced. An autonomous traveling control ECUhas a reconfiguration circuita main power supply circuitan auxiliary current source circuitand a function control unitThe reconfiguration circuitis a reconfigurable logic circuit. The main power supply circuitsupplies a power supply voltage to the reconfiguration circuitThe auxiliary current source circuitincreases or decreases a current supplied from the main power supply circuitto the reconfiguration circuitThe function control unitdetermines an operation mode of the reconfiguration circuiton the basis of a mode determination signal input from the outside and indicating a traveling mode of a vehicle, and controls a reconfiguration of the reconfiguration circuiton the basis of a determination result. The auxiliary current source circuitincreases or decreases the current supplied to the reconfiguration circuitin accordance with a load variation of the reconfiguration circuiton the basis of an auxiliary current control signal for giving an instruction on an increase or decrease of the current supplied to the reconfiguration circuit

Electronic control device, in-vehicle system, and power supply device

A communication device includes a master station, a ring-type transmission line whose start point and end point are connected to the master station, and a plurality of slave stations connected to the ring-type transmission line in parallel. The master station transmits a signal and feeds electric power from both of the start point and the end point of the ring-type transmission line. Each of the slave stations includes an impedance variable element connected to the ring-type transmission line in parallel, and values are set to the impedance variable elements in accordance with the connection positions of the slave stations.

Communication device and automobile including the same

A load drive system for driving a load supplied with power from a power line includes a control unit which controls switching between the power line and the load and a communication unit which communicates using voltage and current of the power line. When performing the switching, the control unit controls, based on a width of a transition period of the power-line current, the transition period being attributable to the switching, timing of the switching so as to move the transition period away from a center of a period corresponding to a symbol communicated by the communication unit.

Load drive system and load drive method

A power line communication device includes a DC power source device, a power line, and a master station that modulates a supply voltage VBUS supplied to the power line according to transmission data to be transmitted. The master station includes a modulation capacitor that is precharged with a modulation amplitude voltage, a polarity switch unit that determines a polarity of the modulation capacitor connected to the power line according to transmission data, and an inductor connected between the DC power source device and the power line.

Power line communication device, in-vehicle device and in-vehicle system

A modulator includes an analog integrator including an analog circuit and a quantizer quantizing its output signal. An external input signal is input thereto. A modulator is coupled to the latter stage of the modulator, and includes a quantizer. A probe signal generation circuit injects a probe signal to the modulator. An adaptive filter searches for a transfer function of the modulator by observing an output signal of the quantizer in accordance with a probe signal. Another adaptive filter searches for a transfer function of the modulator by observing an output signal of the quantizer in accordance with the probe signal. A noise cancel circuit cancels a quantization error generated by the quantizer using search results of the adaptive filters.

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Tokyo, Japan

Tomohiko Yano