Patent application number | Description | Published |
20090261774 | VARIABLE-FLUX MOTOR DRIVE 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. | 10-22-2009 |
20100060223 | PERMANENT MAGNET ROTATING ELECTRICAL MACHINE AND PERMANENT MAGNET MOTOR DRIVE SYSTEM - 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 the 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. | 03-11-2010 |
20100201294 | VARIABLE MAGNETIC FLUX DRIVE SYSTEM - 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 | 08-12-2010 |
20100327689 | PERMANENT-MAGNET-TYPE ROTATING ELECTRICAL MACHINE AND PERMANENT MAGNET MOTOR DRIVE SYSTEM - A permanent-magnet-type rotating electrical machine capable of realizing variable-speed operation in a wide range from low speed to high speed at high output and improving, in a wide operating range, efficiency, reliability, and productivity. The rotating electrical machine includes a first permanent magnet whose product of coercive force and magnetizing direction thickness is small and a second permanent magnet whose product of coercive force and magnetizing direction thickness is large, to form a magnetic pole. The product of coercive force and magnetizing direction thickness of the first permanent magnet is equal to or larger than the product of magnetic field strength and magnetizing direction thickness of the second permanent magnet at a no-load operating point. At the magnetic pole, a magnetic field created by a current of an armature coil magnetizes the first permanent magnet, irreversibly changing a flux amount of the first permanent magnet. | 12-30-2010 |
20100327787 | PERMANENT-MAGNET-TYPE ROTATING ELECTRICAL MACHINE - The present invention provides a permanent-magnet-type rotating electrical machine capable of realizing variable-speed operation in a wide range from low speed to high speed at high output and improving, in a wide operating range, efficiency, reliability, and productivity. A narrow magnetic path | 12-30-2010 |
20110304235 | PERMANENT MAGNET ELECTRIC MOTOR - 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. | 12-15-2011 |
20110309706 | PERMANENT MAGNET ELECTRIC MOTOR - According to one embodiment, a rotor | 12-22-2011 |
20120000739 | ROLLING STOCK SYSTEM AND CONTROL METHOD THEREOF | 01-05-2012 |
20120091848 | PERMANENT MAGNET ELECTRIC MOTOR - 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 ( | 04-19-2012 |