Nidec Corporation

Hiromitsu Ohashi

Yoshiaki Yamashita

Ahmad Ghaderi

Eiji Wada

A motor includes a first inverter electrically connected to a first end of a winding of each phase, and a second inverter electrically connected to a second end of the winding of each phase. Each of the first and second inverters includes low-side switching elements and high-side switching elements. FETs of the first inverter are electrically connected to a first end of a U-phase winding. FETs of the second inverter are electrically connected to a second end of the U-phase winding. At least a portion of a current flowing from one of the FETs of the first inverter to the U-phase winding flows to one of the FETs of the second inverter. One of the FETs of the first inverter and one of the FETs of the second inverter are adjacent to each other.

Motor and electric power steering device

A power conversion device includes a first converter connected to first ends of windings of each phase of a motor, a second converter connected to second ends of the windings of each phase, and a switching circuit used to define a neutral point in the windings of each phase on the first inverter side. At least one of a plurality of switches included in the first inverter has a first current capacity, and a plurality of switches included in the second inverter have a second current capacity that is greater than the first current capacity.

Power conversion device, motor drive unit, and electric power steering device

A power converter includes a first inverter, a second inverter, and a switching circuit including first and second switching elements. In a state in which, in the first inverter, potentials at a first node in a high side and a second node in a low side are equal to each other, and potentials at first ends of two-phase windings of n-phase windings with n being an integer of 2 or more are equal to each other, two-phase windings are energized using two legs connected to second ends of the two-phase windings of n legs of the second inverter while performing switching operations on the first and second switching elements of the switching circuit at a predetermined duty ratio.

Power converter, motor driving unit, and electric power steering device

A motor includes a first inverter connected to one end of a winding of each phase and a second inverter connected to another end of the winding of each phase. The first inverter includes a terminal electrically connected to one end of a U-phase winding. The second inverter includes a terminal electrically connected to another end of the U-phase winding. Current output from the terminal of the first inverter and passing through the U-phase winding flows to the terminal of the second inverter. Current output from the terminal of the second inverter and passing through the U-phase winding flows to the terminal of the first inverter. The terminal of the first inverter and the terminal of the second inverter are adjacent to each other.

A power conversion device includes a first inverter connected to first ends of windings of each phase of a motor, a second inverter connected to second ends of the windings of each phase, a first phase separation relay circuit to switch between connection and disconnection between the first ends of the windings of each phase and the first inverter, a second phase separation relay circuit to switch between connection and disconnection between the second ends of the windings of each phase and the second inverter, a sub-inverter circuit connectable to the first ends and the second ends of the windings of each phase, a third phase separation relay circuit to switch between connection and disconnection between the first ends of the windings of each phase and the sub-inverter circuit, and a fourth phase separation relay circuit to switch between connection and disconnection between the second ends of the windings of each phase and the sub-inverter circuit.

A motor includes a rotor including a rotor core and permanent magnets along an outer periphery of the rotor core, and a stator including windings. Each of the permanent magnets includes a first face in contact with the outer periphery of the rotor core and a second face located outside the first face in a radial direction of the rotor and which faces the stator. In a plan view when the rotor is viewed from a direction parallel to the rotation axis direction of the rotor, the first face includes a linear portion, the second face includes a linear portion parallel to the linear portion of the first face, and a length of the linear portion of the second face is 20% or more and less than 85% of a length of the linear portion of the first face.

Motor and electric power steering apparatus

A power conversion device includes a first inverter connected to first ends of m (m is an integer equal to two or more) coil groups, a second inverter connected to second ends of the m coil groups, m&#x2212;1 separation relay circuits connected between two adjacent coil groups of the m coil groups, m&#x2212;1 first neutral point relay circuits provided between two adjacent coil groups of the first inverter side of each of the m&#x2212;1 separation relay circuits, and m&#x2212;1 second neutral point relay circuits provided between two adjacent coils of the second inverter side of each of the m&#x2212;1 separation relay circuits.

A power conversion device includes a first inverter connected to first ends of windings of each phase of a motor, a second inverter connected to second ends of the windings of each phase, a phase separation relay circuit to switch between connection and disconnection between the first ends of the windings of each phase and the first inverter, a neutral point relay circuit connected to the first ends of the windings of each phase and to switch between connection and disconnection between the first ends of the windings of each phase, a first switching element to switch between connection and disconnection between the second inverter and a power supply, and a second switching element to switch between connection and disconnection between the second inverter and a ground.

A power conversion device includes a first inverter connected to a first end of a winding of each phase of a motor, a second inverter connected to a second end of the winding of each phase, and first and second switching circuits. The power conversion device further includes a normal state operation mode in which power conversion is performed by using a first neutral point of the winding of each phase in the second inverter and the first inverter and an abnormal state operation mode in which the power conversion is performed by using a second neutral point of the winding of each phase in the first inverter and the second inverter. An operation mode of the power conversion is switched from the normal state operation mode to the abnormal state operation mode when at least one switch in the first inverter fails.

A power conversion device includes a first inverter connected to first ends of windings of each phase of a motor, a second inverter connected to second ends of the windings of each phase, and a first switching circuit including at least one of a first switch to switch between whether the first inverter and a power supply are connected or disconnected and a second switch to switch between whether the first inverter and a ground are connected or disconnected. The power conversion device has a first operation mode when the motor is driven at a low speed, and a second operation mode when the motor is driven at a high speed.

Growing community of inventors

Kyoto, Japan

Hiromitsu Ohashi