Yamaha Hatsudoki Kabushiki Kaisha

Atsushi Kurosawa

Haruyoshi Hino

Junji Terada

Tomohiro Ono

Keiko Murota

Hiroaki Yagi

Shinya Naitou

Koushi Sasaki

Katsunori Ubukata

A remaining gas amount calculating device includes a hydrogen tank, an opening/closing valve arranged to deliver hydrogen gas from inside the hydrogen tank, a decompression valve arranged to decompress hydrogen gas delivered from the hydrogen tank, a pressure sensor arranged to measure the pressure of hydrogen gas decompressed with the decompression valve, and a power source system controller arranged to determine the remaining gas amount in the hydrogen tank by calculating the gas pressure in the hydrogen tank based on the hydrogen gas pressure measured with the pressure sensor. The relationship between pressures in a primary chamber and a secondary chamber of the decompression valve is monotonical such that when the pressure in the primary chamber increases, the pressure in the secondary chamber also increases; and when the pressure in the primary chamber decreases, the pressure in the secondary chamber also decreases. The remaining gas amount calculating device makes it possible to calculate the amount of gas remaining in a gas container without using a gas pressure measuring device that measures directly the pressure in the gas container.

Remaining gas amount calculating device

A hybrid power supply system having a fuel cell and a secondary power storage device is used as the power source of a drive motor for a motorcycle. Oxygen supplied from an air blower and hydrogen gas supplied from a hydrogen tank react with each other in the fuel cell to generate electric power. In a warm-up mode, where a temperature of the fuel cell is below a threshold temperature, the fuel cell generates more power than is to be consumed by the drive motor, and the surplus power is used to charge the secondary power storage device. In a normal operation mode, after the warm-up of the fuel cell is completed, the electric power generated by the fuel cell is smaller than the power consumed by the drive motor, and the secondary power storage device supplements the power provided by the fuel cell to meet the power requirement of the drive motor. The hybrid power supply system thus decreases the time needed to warm-up the fuel cell and uses the electric power generated by the fuel cell more efficiently.

Hybrid power supply system and controller for warm-up mode

A DC power source includes one or more insulation type DC-DC converters and a plurality of cells, and is capable of reducing an amount of power loss at an insulation type DC-DC converter. The DC power source includes a pair of terminals for outputting electric power, a fuel cell and a secondary cell connected in parallel to the pair of terminals. An insulation type DC-DC converter is connected in series to either one of the fuel cell or the secondary cell.

DC power source

A motor driven vehicle includes an electric motor that drives wheels through a power source and an electric motor control unit that drives the electric motor. When a voltage of the power source is a predetermined value or greater, the electric motor control unit controls the electric motor such that rotational speed-torque characteristics that the electric motor has are maintained when the voltage of the power source is at the predetermined value.

Motor driven vehicle and method of sampling map data of the motor driven vehicle

An electric vehicle includes a motor, a first controller that controls the motor, a chargeable battery supplying electric power to the motor, a second controller connected to the battery that controls electric charge for the battery and electric discharge from the battery and a first communication path that communicates between the first controller and the second controller. The first and the second controllers each includes a mutual actuating unit for actuating the other controller via the first communication path in response to actuation of the first or second controller.

Electric vehicle

A method for carrying out a boosting operation includes detecting that a boosting operation has been carried out for making a current value of an electric motor larger than a normal full open throttle value, detecting that an electric motor has not rotated, detecting that a predetermined time period has elapsed since the detection that the electric motor has not rotated; and after the detection that the predetermined time period has elapsed, controlling the current value of the electric motor to be equal to or smaller than a limit value that is smaller than the normal full open throttle value.

Growing community of inventors

Shizuoka, Japan

Atsushi Kurosawa