Mitsubishi Electric Corporation

Tatsuya Fukase

Masaki Kato

Masahiko Fujita

Dai Nakajima

Hitoshi Isoda

Naohide Maeda

Saburo Tanaka

Tomoaki Shimano

Jun Tahara

Manabu Horita

Norio Emi

A power semiconductor device is such that a notch provided, along a longitudinal end face of an inner lead, in a region of a lead frame to which the inner lead is bonded. A resistor is disposed, adjacent to the inner lead, on the same side as the notch with respect to the inner lead, and a distance between the inner lead and the notch is set to be smaller than a distance between the inner lead and the resistor, and thereby the inner lead, even when shifted in position, comes into no contact with the resistor. Because of this, it is no more necessary that a space be provided around the inner lead taking into consideration a positional shift of the inner lead, and it is possible to secure the heat release area of power semiconductor chips accordingly, and thus to obtain the small-sized and high-powered power semiconductor device.

Power semiconductor device

Provided is a small-sized power semiconductor device in which interference between power modules adjacently disposed is prevented and the areas of the gaps occurring between the power modules are reduced. In a power semiconductor device formed by adjacently disposing power modules in an arc shape on a heat sink, each of which power modules is obtained by sealing, with a mold resin, a switchable power semiconductor chip, a lead frame in which potential leads and signal terminals connected to the power semiconductor chip are formed, and a metallic inner lead electrically connecting an upper surface electrode of the power semiconductor chip and the lead frame, any one of the adjacent power modules is formed in a pentagonal shape having, at a portion adjacent to the other power module, an oblique sideobtained by cutting out one corner of a quadrangle.

Power semiconductor device and power module

To obtain a compact and high output power conversion device by achieving high heat dispersion performance and a reduction in heat generation, and enabling an efficient arrangement of power modules of three-phase circuits, four switchable power semiconductor chips of each of the power modules are arranged so that two pairs of circuits for one phase connected in series are connected in parallel to form a circuit for two phases, the lead frame includes two positive potential leads, two AC potential leads, and one negative potential lead that are separated from each other, the four switchable power semiconductor chips are individually arranged on four leads of the two positive potential leads and the two AC potential leads, the two positive potential leads each have an end portion connected to a bus bar via a welding point individually provided for each phase, and the bus bar is provided in common.

Power conversion device

When a power semiconductor device is energized, heat generated from upper-side power semiconductor chips mounted on a P-potential electrode transfers to a first heat mass portion and a second heat mass portion, and heat generated from lower-side power semiconductor chips mounted on a intermediate potential electrode transfers to a resistor. A lead frame, the power semiconductor chip, an inner lead and the resistor are placed in symmetry with respect to a centerline, which can reduce the difference among the temperature increases of the power semiconductor chips when energized. In this way, transient temperature increase of the power semiconductor chip can be suppressed without adding a new member, such as a heat diffusion plate.

To obtain a rotating electrical machine preventing a functional failure and shortening of the life of brushes caused by a temperature rise of the brushes installed to a vehicle AC power generator or a motor generator. A brush holder holding brushes supplying a field current to a rotor is provided with brush temperature suppressing metal members installed substantially parallel to the brushes in the vicinity of abutment portions of the brushes and slip rings in point-, line-, or surface-contact with the brushes at least at one point besides energization terminals. The brush temperature suppressing metal members not only diffuse heat generated at the brushes, but also function as a heat capacity for a case where a large amount of heat is generated in a short time, such as during regenerative power generation and a start-up operation, and thereby prevent an excessive temperature rise of the brushes.

Brush structure with heat dissipation member

According to a power semiconductor device of the present invention, it comprises a plurality of lead frames formed into like a wiring pattern, a power semiconductor element joined onto the lead frame, and a capacitor placed between mutually adjacent two lead frames, and is encapsulated with a mold resin. The capacitor is characterized in that external electrodes of that capacitor are connected to the lead frames each through a stress-relaxation structure portion that is lower in rigidity than the capacitor.

A rotary electric machine including a brush used to supply a field current to a field winding of a rotor, a brush holder holding the brush, a power circuit portion connected to a heat sink having fins, and a case covering the power circuit portion and the brush holder. An air passage is provided between the brush holder and the fins of the heat sink, and an opening is provided to the case so as to cover component members of the brush holder in a shape conforming to an outer peripheral portion of the brush holder, from which cooling air is allowed to pass through the air passage.

Rotary electric machine

An electric rotating machine is provided that efficiently radiates heat, caused in the vicinity of a portion where a brush and a slip ring makes contact with each other, to the outside of a brush holder and that can prevent the temperature of the brush from excessively rising. The brush holder holding the brush that supplies a magnetic-field current to a magnetic-field winding by way of the slip ring is provided with an energization terminal that electrically connects a magnetic-field circuit with the brush and a brush cooling metal member that cools the brush; the brush cooling metal member radiates heat, generated in the vicinity of a contact portion between the brush and the slip ring, to the outside of the brush holder.

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Tokyo, Japan

Tatsuya Fukase