Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric Corporation

Kiyoyuki Ishikawa

Keiichi Ito

Noboru Hosokawa

Yasuji Yoshizumi

Tetsuya Matsuda

Takao Tsurimoto

Koji Kise

Hirotaka Muto

Soichiro Kainaga

Ryuichi Nishiura

Kosei Tsuji

Takahiko Ishikura

Yasuo Toba

Hiroki Otera

Koji Shinya

Taketoshi Hasegawa

In a stationary induction apparatus, an inter-partial-coil insulating plate and a plurality of inter-partial-coil spacer insulators form a refrigerant flow path in conjunction with each other. A space having an inter-partial-coil insulation dimension for withstanding an abnormal voltage is formed between a pair of partial coils. The inter-partial-coil insulating plate and the inter-partial-coil spacer insulators support both the pair of partial coils at an insulated state so as to maintain the inter-partial-coil insulation dimension. The insulators are arranged so as to be overlapped with each other in the direction in which mutually adjacent partial coils are opposed to each other.

Stationary induction apparatus

In an electric apparatus, insulating cylinders having different diameters are arranged in a shape of multiple cylinders between the iron core and the low voltage winding, between the low voltage winding and the high voltage winding and on the periphery of the high voltage winding. Spacers are separately arranged between layers of the plurality of insulating cylinders to form a plurality of insulating medium paths. A flow stopping member for stopping the flow of the insulating medium in the insulating medium paths which is made of an insulating material with a low density is arranged at at least one of the upper and lower ends of each of the insulating medium paths.

Electric appliance

A stationary induction apparatus superior in insulating ability against a surge voltage includes a coil piece on a line end side surrounded by one electrostatic shield insulating layer. The coil piece and electrostatic shield insulating layer, together with another coil piece, are surrounded by another electrostatic shield insulating layer, thus forming a successively nested configuration. Each of the electrostatic shield insulating layers includes an electrical insulating layer of pressboard and first and second conductive layers respectively located on inner and outer surface sides of the electrical insulating layer, The capacitance of each of the electrostatic shield insulating layers is adjusted to control an electrical potential distribution upon application of a surge voltage.

Growing community of inventors

Tokyo, Japan

Kiyoyuki Ishikawa