Kabushiki Kaisha Toshiba

Toshiba Industrial Products Manufacturing Corporation

Other

Toshiba Industrial Products and Systems Corporation

Kazuto Sakai

Norio Takahashi

Tomoyuki Hattori

Makoto Matsushita

Masanori Arata

Kazuaki Yuuki

Yutaka Hashiba

Tadashi Tokumasu

Motoyasu Mochizuki

Yusuke Matsuoka

Mikio Takabatake

Hiroshi Mochikawa

Yoshio Hashidate

Masakatsu Matsubara

Yosuke Nakazawa

Ryoichi Kurosawa

Wataru Ito

Takashi Hanai

Yasuo Hirano

Takashi Araki

Daisuke Misu

Yukihiko Kazao

Yosuke Otsubo

Yutaka Tabuchi

Kuniyuki Araki

Hirotsugu Tsutsui

Shiro Amemori

Koji Oishi

A rotary electric system includes a rotary electric device that includes: a stator including a stator winding; and a rotor. The stator winding includes: a first coil group that generates a rotating magnetic field to rotate the rotor; and a second coil group that generates power with induced electromotive force due to rotation of the rotor.

Rotary electric system

A variable-flux motor drive system including a permanent-magnet motor including a permanent magnet, an inverter to drive the permanent-magnet motor, and a magnetize device to pass a magnetizing current for controlling flux of the permanent magnet. The permanent magnet is a variable magnet whose flux density is variable depending on a magnetizing current from the inverter. The magnetize device passes a magnetizing current that is over a magnetization saturation zone of magnetic material of the variable magnet. This system improves a flux repeatability of the variable magnet and a torque accuracy.

Variable-flux motor drive system

According to one embodiment, a rotor is configured by a rotor core and magnetic poles. Two or more types of permanent magnets are used such that each product of coercivity and thickness in the magnetization direction becomes different. A stator is located outside the rotor with air gap therebetween and configured by an armature core winding. At least one permanent magnet is magnetized by a magnetic field by a current of the armature winding to change a magnetic flux content thereof irreversibly. A short circuited coil is provided to surround a magnetic path portion of the other permanent magnet excluding the magnet changed irreversibly and a portion adjacent to the other permanent magnet where the magnetic flux leaks. A short-circuit current is generated in the short circuited coil by the magnetic flux generated by conducting a magnetization current to the winding. A magnetic field is generated by the short-circuit current.

Permanent magnet electric motor

A variable magnetic flux motor drive system includes: a variable magnetic flux motor having a variable magnet which is a low-coercive permanent magnet; an inverter that drives the variable magnetic flux motor; an inverter as a magnetization unit which supplies a magnetization current for controlling a magnetic flux of the variable magnet; and a boosting unit boosting an input DC voltage to a predetermined target value to output it to the inverter. The variable magnetic flux motor drive system makes it possible to achieve size reduction and high efficiency, while securing a voltage required for supplying a magnetization current when controlling the magnetic flux of the variable magnet.

Variable magnetic flux motor drive system

An increase of the magnetization current can be restrained during demagnetization and magnetization, and a variable speed operation can be achieved at a high power output over a wide range of from a low speed to a high speed. A rotoris configured by a rotor core, permanent magnetshaving a small value as the product of the coercivity and the thickness in the magnetization direction thereof, and permanent magnetshaving a large value as the product. When reducing a flux linkage of the permanent magnets, a magnetic field directed to the reverse direction of the magnetization direction of the permanent magnetsdue to a current of an armature coil is caused to act on them. When increasing a flux linkage of the permanent magnets, a magnetic field directed to the same direction as the magnetization direction of the permanent magnetsdue to a current of an armature coil is caused to act on them. A short circuit coilis located in a magnetic path part of each permanent magnetother than the permanent magnets. A magnetic field due to a magnetization current induces an induced current to generate a magnetic field on the periphery of the short circuit coil. The generated magnetic field and the magnetization current generate a magnetic field to magnetize the permanent magnets

Permanent magnet electric motor inducing short circuit current in short circuit coil

A rotor has rotor cores divided in the axial direction. A permanent magnet is mounted at the position of each of the magnetic poles of cores. The permanent magnet of each magnetic pole is configured by a single tabular member that penetrates the two divided cores in the axial direction. Convex parts are respectively provided on the outer peripheries of the respective magnetic poles of the rotor cores along the axial direction of the rotor. The convex parts are provided to positions that are displaced for each of the two divided cores. The magnetic flux density increases in the convex parts, which becomes the magnetic pole center. Since the convex parts positions are displaced to each other, a skew function can be exhibited even if the permanent magnet is mounted at the same position.

An increase of the magnetization current can be prevented during demagnetization and magnetization, and a variable speed operation can be achieved at a high power output over a wide range of from a low speed to a high speed. A rotor () is configured by a rotor core (), a variable magnetic force magnet () and a fixed magnetic force magnet (). A variable magnetic force magnet () and a fixed magnetic force magnet () are overlapped in the magnetization direction thereof to form a series of magnets. The series of magnets is located within the rotor core at a position where the magnetization direction is in the direction of a d-axis. On either side of the series of magnets of the variable magnetic force magnet () and the fixed magnetic force magnet (), fixed magnetic force magnets () are located at a position where the magnetization direction is in the direction of the d-axis. When the flux linkage of the variable magnetic force magnet is reduced, a current of an armature coil allows a magnetic field to act in the reverse direction to the magnetization direction of the variable magnetic force magnet. When the flux linkage of the variable magnetic force magnet is increased, a current of the armature coil allows a magnetic field to act in the same direction as the magnetization direction of the variable magnetic force magnet.

According to one embodiment, a permanent-magnet type electric rotating machine has a stator, a magnetizing coil, a rotor and a case. The stator has an armature coil configured to form a magnetic circuit for driving. The magnetizing coil is configured to form a magnetic circuit for magnetizing. The rotor has a constant magnetized magnet, a rotor core and a variable magnetized magnet. The rotor core holds the constant magnetized magnet. The constant magnetized magnet is arranged closer to the magnetic circuit for driving than the variable magnetized magnet. The variable magnetized magnet is arranged closer to the magnetic circuit for magnetizing than the constant magnetized magnet.

Permanent-magnet type electric rotating machine

A rotor for a rotating electrical machine suppresses demagnetization of permanent magnets without deteriorating motor characteristics, is low-cost, and is highly reliable. The rotor has a plurality of rotor cores that are stacked together, a plurality of permanent magnets axially divided by the rotor cores and circumferentially arranged on each of the rotor cores, to circumferentially form magnetic irregularities, and a rotor blank made of nonmagnetic material arranged between those of the rotor cores that are adjacent to each other.

Rotor for rotating electrical machine

A permanent magnet rotating electrical machine capable of conducting a variable speed operation at high output in a wide range from low speed to high speed and improving efficiency and reliability in a wide operating range. Two kinds of permanent magnets having different shapes or different magnetic characteristics are embedded in a rotor core, to form a magnetic pole. The permanent magnets arranged at the magnetic pole include a permanent magnet whose product of coercive force and thickness along a magnetizing direction is small and a permanent magnet whose product of coercive force and thickness along the magnetizing direction is large. A magnetic field created by passing a current to an armature coil for a short time is used to irreversibly magnetize the permanent magnet whose product of coercive force and thickness along magnetizing direction is small, thereby changing a total linkage flux amount, and a positive d-axis current is passed when torque is large.

Permanent magnet rotating electrical machine and permanent magnet motor drive system

Growing community of inventors

Yokosuka, Japan

Kazuto Sakai