Abstract: A stable motor control characteristics can be accomplished by correcting a q-axis current command value by a product of a d-axis current command value (or a detected current value) calculated by field weakening control and a sine signal which is a phase difference between the reference axis of control and the reference axis of the motor. Thereby, a “field weakening vector controller for the permanent magnet synchronous motor” which accomplishes a high-precision, high-response, and high-stability motor torque control even in a field weakening region and which is applicable both to an inexpensive current detecting system and to a system without a pole position detector is provided.

Abstract: A motor controller capable of suppressing a large speed change generated at the time of changeover from a synchronous operation mode to a position feedback operation mode and implementing even acceleration characteristics regardless of the load torque by estimating a torque of a permanent magnet motor in the synchronous operation mode for driving the permanent magnet motor and setting an initial value of a current command value in a position sensor-less operation mode on the basis of information of the torque estimated value.

Abstract: A rotation transmitting apparatus according to the present invention includes a first sun gear, a second sun gear, first planetary gears and second planetary gears. A carrier for supporting the respective planetary gears is integrally provided with a rotor of a speed change motor for changing a speed of rotation to be transmitted, so that the number of mesh portions in the gears is reduced. Further, the rotor is formed of a cylindrical shape and an input shaft for rotating the first sun gear is inserted into the rotor, so that a limited space is effectively used.

Abstract: A differential gear apparatus according to the present invention comprises a first sun gear coupled to a first shaft to be rotated in conjunction with the first shaft, a second sun gear coupled to a second shaft to be rotated in conjunction with the second shaft, a first planetary gear meshed with the first sun gear, a second planetary gear rotated with the first planetary gear and meshed with the second sun gear, a carrier supporting the first and second planetary gears, and a housing supporting the second shaft upon rotation, wherein the sun gears and the planetary gears have profile shifted teeth of which addendum modifications are different at the positions in a flank width direction and a nut screwed on the mid way of the second shaft, and a through hole disposed at a position facing the nut are provided.

Abstract: A polyelectrolyte for a solid polymeric fuel cell comprising an aromatic polyether sulfone block copolymer comprising a hydrophilic segment containing sulfonic acid groups and a hydrophobic segment having no sulfonic acid group at a hydrophilic segment weight fraction W2 to hydrophobic segment weight fraction W1 ratio falling within a range of 0.6<W2/W1<2.0. The polyelectrolyte for a solid polymeric fuel cell is inexpensive and durable, and its proton conductivity is less influenced by humidity and temperature.

Abstract: Compatibility with a current transformer having several kinds of rated current ratios is achieved by finding out a formula of relationship between errors arising in a transformer input circuit and detectable ranges set as setting values of the input circuits which can be optimally set. In connection with that, by dispensing with a gain control section, the number of components, the mounting area and the cost can be reduced. Arithmetic expressions representing the relationship among errors arising in the transformer input circuit, the instrumentation ranges of the input circuits, and detectable errors have been derived. Further by optimally setting the detectable ranges of the input circuits, which are the parameters of the arithmetic expressions, the configuration compatible with a current transformer having several kinds of rated current ratios is achieved.

Abstract: Compatibility with a current transformer having several kinds of rated current ratios is achieved by finding out a formula of relationship between errors arising in a transformer input circuit and detectable ranges set as setting values of the input circuits which can be optimally set. In connection with that, by dispensing with a gain control section, the number of components, the mounting area and the cost can be reduced. Arithmetic expressions representing the relationship among errors arising in the transformer input circuit, the instrumentation ranges of the input circuits, and detectable errors have been derived. Further by optimally setting the detectable ranges of the input circuits, which are the parameters of the arithmetic expressions, the configuration compatible with a current transformer having several kinds of rated current ratios is achieved.

Abstract: Compatibility with a current transformer having several kinds of rated current ratios is achieved by finding out a formula of relationship between errors arising in a transformer input circuit and detectable ranges set as setting values of the input circuits which can be optimally set. In connection with that, by dispensing with a gain control section, the number of components, the mounting area and the cost can be reduced. Arithmetic expressions representing the relationship among errors arising in the transformer input circuit, the instrumentation ranges of the input circuits, and detectable errors have been derived. Further by optimally setting the detectable ranges of the input circuits, which are the parameters of the arithmetic expressions, the configuration compatible with a current transformer having several kinds of rated current ratios is achieved.

Abstract: Compatibility with a current transformer having several kinds of rated current ratios is achieved by finding out a formula of relationship between errors arising in a transformer input circuit and detectable ranges set as setting values of the input circuits which can be optimally set. In connection with that, by dispensing with a gain control section, the number of components, the mounting area and the cost can be reduced. Arithmetic expressions representing the relationship among errors arising in the transformer input circuit, the instrumentation ranges of the input circuits, and detectable errors have been derived. Further by optimally setting the detectable ranges of the input circuits, which are the parameters of the arithmetic expressions, the configuration compatible with a current transformer having several kinds of rated current ratios is achieved.