Toyota Jidosha Kabushiki Kaisha

Denso Corporation

Wataru Nakayama

Kenji Goto

An electric power control unit configured to control drive power of a three-phase alternating current to be supplied to an electric motor may include: an inverter configured to convert a direct current to the three-phase alternating current; first and second current sensors, each of which is configured to measure a first-phase current in the three-phase alternating current; third and fourth current sensors, each of which is configured to measure a second-phase current in the three-phase alternating current; and a controller configured to control the inverter, and under a condition in which the first current sensor fails, when measured values of the second, the third, and the fourth current sensors do not coincide with each other while the inverter is shut down, the controller may stop to further supply the drive power to the electric motor.

Electric power control unit

A method of estimating a temperature of a reactor provided in a boost converter disclosed herein, a temperature of a bus bar connected with the reactor and a current flowing in the bus bar are measured; when an absolute value of a DC component ILdc of the measured current exceeds a current threshold Ith, an estimated value of the temperature of the reactor is calculated by adding a first correction value, which depends on the DC component ILdc, to the measured temperature TL and is outputted as an estimated temperature TR; and when the absolute value of the DC component is lower than the current threshold Ith, the estimated value of the temperature of the reactor is calculated by adding a second correction value, which does not depend on the measured current, to the measured temperature and is outputted as the estimated temperature TR.

Method of estimating temperature of reactor

A bus bar module equipped with a current sensor includes a first bus bar, a second bus bar, a substrate, and a first magnetoelectric transducer. The first bus bar has a first notch. The second bus bar has a second notch and is placed in parallel to the first bus bar. The second notch is provided at a position different from the first notch in an extending direction of the first bus bar. The substrate is fitted to both the first notch and the second notch. Further, the substrate is sandwiched between those side surfaces of the first bus bar and the second bus bar which are opposed to each other. The first magnetoelectric transducer is placed inside the first notch and fixed to the substrate.

Bus bar module

A bus bar module includes a first bus bar, a second bus bar, and a first magnetoelectric transducer. The second bus bar is placed in parallel to the first bus bar. The first magnetoelectric transducer is placed so as to be opposed to a side surface of the first bus bar. A sectional area of the first bus bar is smaller than a sectional area of the second bus bar in a first section. The first section is a section passing through the first magnetoelectric transducer and perpendicular to an extending direction of the first and second bus bars.

A current sensor is configured to measure current flowing in two bus bars aligned in an X direction and extending parallel in a Y direction. A sensing element is arranged such that its magnetism sensing direction is oriented in the X direction on a line passing through the bus bar in a Z direction. A pair of shield plates sandwiches the bus bar and the sensing element therebetween in the Z direction. The bus bar is located between the sensing element and the lower shield plate. The sensing element is located closer to the upper shield plate than to the lower shield plate. At least one of a thickness and a magnetic permeability of the magnetism shield plates is greater in the upper shield plate than in the lower shield plate.

Current sensor

A power supply system for an electric vehicle includes a battery, an inverter configured to supply alternating-current electric power to a motor for traveling, a first voltage converter connected between the battery and the inverter, a second voltage converter connected in parallel with the first voltage converter, a temperature acquisition unit configured to acquire a temperature of the first voltage converter, a current acquisition unit configured to acquire magnitude of a current flowing in the second voltage converter, and a controller. Each of the first voltage converter and the second voltage converter includes two switching elements, two diodes, and a reactor.

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Toyota, Japan

Wataru Nakayama