Denso Corporation

Denso Corpora Tion

Seikoh Arimura

Tomonori Kimura

Hiroshi Taki

Takashi Masuzawa

Hitoshi Yoshimura

A cooling device has a cooler, a circulator, a semiconductor temperature detection unit, a refrigerant temperature detection unit, an output acquisition unit, and a flow velocity control unit. An output area of a power converter is divided into a first output area equal to and smaller than a threshold and a second output area exceeding the threshold. The flow velocity control unit controls, in the first output area, the flow velocity of the refrigerant to be maintained within a range where the refrigerant in the heat receiving portion is kept in a non-boiling state; and controls, in the second output area, the flow velocity to be maintained within a range where the refrigerant is in the non-boiling state or a nucleate boiling state. The flow velocity in the second output area is equal to or greater than an upper limit value of the flow velocity in the first output area.

Cooling device

The present application presents a power conversion control device that does not reduce electric power conversion efficiency. A mode judging section judges whether a direction of current flowing through an inductor has been reversed or not based on both an average value of current flowing through the inductor, the average value being calculated by an average current calculating section, and a difference (i.e peak current) between a maximum value and a minimum value of a current flowing through the inductor, the difference being calculated by a peak current calculating section. And then if the judging section has determined that the direction of current flowing through an inductor has been reversed, the power conversion control device makes the switching elements ON/OFF-operation corresponding to either one of a power running mode or an electric power regenerating mode.

Power conversion control device and power conversion device using the same

The control apparatus for a power conversion apparatus having chopper circuits and a capacitor, each of which includes a switching circuit and a coil, the switching circuit being on/off-controlled in accordance with specific timings determined in accordance with a current flowing through the coil to create required voltage in the capacitor, includes a function of evenly dividing an interval between adjacent specific timings of one of the chopper circuits to produce divided timings to be allocated to the other chopper circuits, and a function of setting, for each of the other chopper circuits, an on-time period of the switching circuit such that, when the interval varies as a result of which the specific timing of each of the other chopper circuits deviates from a corresponding one of the divided timings, an interval between adjacent specific timings of each of the other chopper circuits is varied to reduce the deviation.

Growing community of inventors

Kariya, Japan

Seikoh Arimura