Denso Corporation

Kyushu University

Kousuke Nomura

Ryosuke Sakai

Norihiro Kurumado

Ichiro Sasada

Masaki Takashima

Takamasa Kinpara

A semiconductor device includes: power elements that configures an inverter; a conductive plate that electrically connects the power elements; and a current detection portion. The power elements include a first power element and a second power element. The conductive plate includes: a first carrying portion; a second carrying portion; a third carrying portion; a fourth carrying portion; a first connection portion that electrically connects the second carrying portion and the third carrying portion to connect the first power element and the second power element in series; and an output terminal electrically connected with the second carrying portion or the third carrying portion. The first carrying portion is connected with a first power source and the fourth carrying portion is connected with a second power source. The current detection portion is fixed to the output terminal and the magnetic field permeates the current detection portion.

Semiconductor device with power elements and current detection portion

A current detection system includes: first and second magnetic plates arranged in parallel with a predetermined distance; a bus bar for flowing current; and a magneto-electric conversion element converting a lateral direction component of a measurement object magnetic flux, generated by current flowing through the bus bar, to an electric signal. When an external magnetic flux in a lateral direction passes through an accommodation space between the first and second magnetic plates, a trajectory of the external magnetic flux is bent by the first and second magnetic plates, and the accommodation space is divided into a permeable space, through which the external magnetic flux passes, and a non-permeable space, through which the external magnetic flux does not pass. The bus bar is arranged in the accommodation space. The magneto-electric conversion element is arranged in the non-permeable space. The bus bar and the magneto-electric conversion element are lined in the height direction.

Electrical current detection system

In a current sensor for detecting an electric current flowing in a current path, a magnetic field generating element generates a second magnetic field perpendicular to a first magnetic field generated by the electric current of the current path, and a magnetic sensor generates at least one of a first signal containing a sine value according to an angle defined between the second magnetic field and a synthetic magnetic field composed of the first magnetic field and the second magnetic field and a second signal containing a cosine value according to the angle. A signal processing unit includes a calculation circuit that calculates a tangential value according to the angle using the at least one of the first signal and the second signal, and outputs a sensor signal containing the tangential value.

Current sensor and attachment structure of the same

A current sensor includes: a magneto electric conversion element; and a magnetic field concentrating core applying a magnetic field caused by a measurement object current to the magneto electric conversion element. A planar shape of the magnetic field concentrating core perpendicular to a current flowing direction is a ring shape with a gap. The magneto electric conversion element is arranged in the gap. A part of a conductor for flowing the current is surrounded by the magnetic field concentrating core. The magnetic field concentrating core includes two first magnetic members and at least one second magnetic member, which are stacked alternately in the current flowing direction. Parts of the two first magnetic members adjacent to each other via the one second magnetic member are opposed to each other through a clearance or an insulator.

Current sensor

A current sensor for measuring a current flowing through a conductor includes a sensor substrate, a magnetoelectric converter formed on a surface of the sensor substrate and configured to output a signal changing with an applied magnetic field, and a magnetic shield that surrounds the sensor substrate and the conductor to magnetically shield the inside from the outside. The output signal of the magnetoelectric converter changes with a magnetic filed applied along the formation surface of the sensor substrate. The magnetic shield has at least one gap for reducing magnetic saturation in the magnetic shield. The gap and the sensor substrate are located at the same height in a z-direction orthogonal to the formation surface of the sensor substrate.

A current sensor for detecting a first electric current flowing through a current path includes a sensor chip, a coil, a current control circuit, and an output circuit. The sensor chip includes a magnetoresistive element and is adopted to be located near the current path. The coil applies a bias magnetic field to the magnetoresistive element. The current control circuit supplies a second electric current to the coil. The second electric current periodically changes in polarity. The output circuit outputs a difference between a first voltage and a second voltage. The first voltage is generated by the magnetoresistive element, when the second electric current flowing through the coil has a positive polarity. The second voltage is generated by the magnetoresistive element, when the second electric current flowing through the coil has a negative polarity.

Growing community of inventors

Nagoya, Japan

Kousuke Nomura