Mitsubishi Electric Corporation

International Business Machines Corporation

Sony Corporation

Atsushi Tsuchiya

Kazunori Hatakeyama

Keisuke Uemura

Gaku Yamamoto

Yuichi Shimizu

Hiromi Ishikawa Ishikawa

Koichi Arisawa

Takashi Yamakawa

Kenji Iwazaki

Shinya Toyodome

A power converter including: a non-boost rectifier circuit that converts a first alternating-current voltage into a direct-current voltage; a reactor connected to the rectifier circuit; a capacitor that smooths a direct-current voltage; an inverter that is connected in parallel to the capacitor, converts the smoothed direct-current voltage into a second alternating-current voltage having desired voltage and frequency, and outputs the second alternating-current voltage to a motor; and a controller that controls an operation of the inverter. Capacitances of the reactor and the capacitor are set such that a resonance frequency of a filter circuit including the reactor and the capacitor is smaller than a first electrical angular frequency based on a voltage command when the controller controls an operation of the inverter such that the second alternating-current voltage is maximized in a range not causing overmodulation.

Power converter and air conditioner

Included are a rectifier circuit that rectifies a first alternating-current voltage; a reactor connected to the rectifier circuit; a capacitor connected to an output end of the rectifier circuit; an inverter that is connected to the capacitor, generates a second alternating-current voltage through operations of a plurality of switching elements, and applies the second alternating-current voltage to a motor including a stator and a rotor; and a control unit that performs operation controls on the plurality of switching elements. The control unit causes the inverter to apply, to the motor, the second alternating-current voltage having a higher frequency than when the motor is in compression operation so as not to rotate the rotor. The application of the high-frequency second alternating-current voltage from the inverter to the motor generates a regenerative current and a current flows to the capacitor due to the regenerative current without impairing the capacitor.

Power conversion apparatus and air conditioner

A motor driving device includes: a connection switcher that has an electromagnetic contactor connected to a winding of a motor and switches connection condition of the winding by switching condition of the electromagnetic contactor; an inverter to apply an output voltage as an AC voltage to the winding via the connection switcher; a short-circuiting circuit having a rectification circuit and a switch; and a controller to control the electromagnetic contactor, the inverter and the switch, wherein a circulating circuit is formed by the short-circuiting circuit and the winding when the switch is set at ON, and the connection switcher switches the connection condition of the winding in a period in which the output voltage of the inverter is set at zero in a rotating operation of the motor and a current caused by the rotating operation circulates in the circulating circuit.

Motor driving device and air conditioner

A motor driving device is a device for driving a motor including stator windings, includes: a connection switching unit that is connected to the stator windings, includes circuits including semiconductor switches, and switches connection condition of the stator windings to either of first connection condition and second connection condition different from the first connection condition by setting the semiconductor switches to ON or OFF; and an inverter that supplies AC drive voltages to the stator windings.

A motor driving apparatus for driving a motor, the apparatus being connected to the motor by first, second, and third connection lines respectively corresponding to first, second, and third phases, the apparatus including: an inverter converting direct-current voltage into three-phase alternating-current voltage by using first, second, and third switching element pairs respectively connected to the first, second, and third connection lines, and outputting the three-phase alternating-current voltage to the motor; a voltage detection circuit detecting a first voltage based on a potential difference between a potential of the first connection line and a reference potential; and a control unit calculating a voltage value of the direct-current voltage based on the first voltage during a first period in which an upper-arm switching element of the first switching element pair is on, controlling operation of the inverter according to the voltage value, and changing the first period according to the voltage value.

Motor driving apparatus and air conditioner using the same

A motor driving device that is a device for driving a motor including stator windings, includes: a connection switching unit that includes relays as mechanical switches connected to the stator windings and excitation coils opening or closing the relays by being energized or non-energized with excitation current and switches connection condition of the stator windings to either of first connection condition (star connection) and second connection condition (delta connection) different from the first connection condition by opening or closing the relays; and an inverter that supplies AC drive voltages to the stator windings.

The motor driving apparatus includes a switch that is a mechanical switch for changing coil connection states of a motor; an inverter that generates alternating voltage from direct voltage and outputs the alternating voltage to the motor; and a control device that controls the switch and the inverter. The control device causes the switch to change the coil connection states while the alternating voltage output from the inverter is zero.

Motor driving apparatus, refrigeration cycle system, air conditioner, water heater, and refrigerator

A motor driving device includes an inverter to supply an alternating current, a switch unit that switches the number of at least one permanent magnet synchronous motor to which the alternating current is supplied from the inverter, a detector to detect a detection value corresponding to the alternating current supplied to the at least one permanent magnet synchronous motor, and a control device to control the inverter and the switch unit. The control device sets an overcurrent interruption threshold value at a value based on the number. When the detection value is greater than or equal to the overcurrent interruption threshold value, the control device makes the inverter stop the supplying of the alternating current to the at least one permanent magnet synchronous motor.

Motor driving device, circuitry for controlling motor driving device, control method of motor driving device, and air conditioner

Mobile objects and resources are managed by a system including a mobile object server operable to receive information from a plurality of mobile objects in a geographic space, and an event server in communication with the mobile object server. The event server is operable to receive, from the mobile object server, resource utilization information indicating a resource in the geographic space that each mobile object is scheduled to use, calculate a state of use of the resource based on a predicted arrival time of each mobile object at the resource, and send a recommendation for relaxing congestion of the resource.

Management of mobile objects and resources

To avoid congestion and ease traffic jams of mobile objects while managing movement of a plurality of mobile objects in a geographic space, provided is a system including a mobile object server operable to assist with movement of a plurality of mobile objects in a geographic space; and a priority control module operable to perform priority movement control that causes a mobile object having high priority to be prioritized over and progress ahead of a mobile object having low priority, based on priorities assigned to each of a plurality of mobile objects. Also provided are a method and program.

Management of mobile objects

Evacuation of mobile objects is managed by a system including a processor; and one or more computer readable mediums collectively including instructions that, when executed by the processor, cause the processor to receive information of occurrence of a disaster, obtain information of a plurality of evacuation areas, obtain a plurality of locations, each location corresponding to a mobile object among a plurality of mobile objects in a geographic space, distribute the plurality of mobile objects into the plurality of evacuation areas according to a distribution based on the information of the plurality of evacuation areas and the plurality of locations.

Management of evacuation with mobile objects

A terminal can play back song or video information in real time without downloading it, and thus restrictions on the hardware of the terminal are reduced and a large amount of music can be listened to anytime and anywhere. Also, the user can listen to music more cheaply than if it was downloaded, and copyright problems are reduced. Further, the terminal is charged based on the playback time or the amount of information. Accordingly, when the user stops playback because he or she does not like a song, the price is less than it is when the user listens to the song to the end, and thus the user can feel free to use this service.

Growing community of inventors

Tokyo, Japan

Atsushi Tsuchiya