Denso Corporation

Yuuji Kamiya

Koji Sakai

Tomoyuki Sumi

Hidenori Akita

Toshiya Saito

Hideyuki Morita

Teruaki Ohyama

An electric compressor includes a compression portion discharging a high pressure refrigerant by compressing a low-pressure drawn refrigerant, an electric motor driving the compression portion with a rotation of a rotor, a motor drive circuit driving the electric motor, an intermediate pressure port through which an intermediate pressure refrigerant is introduced into the compression portion, and a controller performing a rotation control of the rotor. When the controller stops the electric motor in a two-step compression mode in which the intermediate pressure refrigerant is introduced into the compression portion, the controller stops the rotor rotating by performing short-circuit braking on the electric motor and then fixes a rotational position of the rotor at a predetermined rotational position by performing direct current excitation on the electric motor.

Electric compressor

A CPU drives an inverter based on a command rotation speed that is inputted from a higher level ECU at a predetermined update interval. The CPU acquires an actual rotation speed of the electric motor, and calculates an accelerated rate and a decelerated rate based on the update interval and a difference between the actual rotation speed and the command rotation speed such that the actual rotation speed changes without reaching the command rotation speed and becoming constant before an end of the update interval. The CPU drives the inverter such that the electric motor rotates at the calculated rate.

In-vehicle electric motor control device

An inter-vehicle communication device that is connected to a wide-area communication terminal determines a dedicated short-range communication resource assignment by using a wide-area communication resource assignment that is assigned to the wide-area communication terminal. Since a plurality of terminals are not assigned to the same resource block in the wide-area communication resource assignment, the dedicated short-range communication resource assignment determined by using the wide-area wireless communication resource assignment can also prevent a plurality of terminals from being assigned to the same time slot. The wide-area communication resource assignment is essentially necessary for the communication between a base station communication device and the terminals. Since the wide-area communication resource assignment which is necessary is used to determine the dedicated short-range communication resource assignment, a limit to the amount of downlink data can be reduced.

Growing community of inventors

Kariya, Japan

Yuuji Kamiya