Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric Corporation

Kiyoshi Eguchi

Takayoshi Ishikawa

Shigemi Tamaru

Yasushi Genba

Toshihiko Kodera

Susumu Satou

Hideshi Takashita

Keita Hatanaka

Masaki Kono

Yoshihiko Kinpara

Mitsuo Kashima

Mahito Unno

Yoshinori Mochizuki

Akira Hatai

Tsutomu Sera

Kouichi Arisawa

Masayuki Okada

Masakatsu Daijou

A control controls starting of an AC rotary machine by calculating a resistance drop component, corresponding to a resistance drop of the AC rotary machine, based on a detection current, and adjusts angular frequency of an AC output voltage based on subtracting the resistance drop component from a voltage command, and, simultaneously, adjusting amplitude of the AC output voltage so that amplitude of an AC phase current may change in conformity with a predetermined function.

Control apparatus for AC rotary machine

In the inverter device of the invention, when a power source connected to an electrolytic capacitoris interrupted, a switching control circuitcontrols switching elements of an inverter main circuitto operate to supply a current to a load, thereby discharging charges of the electrolytic capacitor, and an electrolytic capacitor electrostatic capacitance calculatorcalculates the electrostatic capacitance of the electrolytic capacitor, on the basis of: a discharged charge amount which is obtained from an outflow current Ic from the electrolytic capacitor, and a discharge time; and a discharge voltage &#x394;V which is a voltage drop from beginning of discharging of the electrolytic capacitor

Inverter device

In an electric motor control system according to the present invention, in restarting, after the effect of transient variation has been abated, a phase-reversal-timing detecting meansdetects the first maximal value V, the first minimal value V, and the second maximal value V, by comparing a value of the integration term of the d-axis component vds* of the 2-phase-voltage command outputted from the d-axis current control meanswith its previous value, and then outputs a time at which the value of the integration term of the d-axis component vds* of the 2-phase-voltage command becomes below (the first minimal value V+the second maximal value V)/2, as the first specific phase at which the current-commanding phase is turned by 180 degrees, to the current phase commanding means

Motor controller

A control circuit calculates, through PI control, the amplitude of a current command per half cycle of an input voltage at a point in time where the sign of the input voltage from the AC power supplydetected by an input voltage detectorchanges based on the difference between a reference voltage command and the voltage of a capacitor detected by a DC voltage detector, calculates a normalized current command by dividing the amplitude of the current command by the peak value of the last input voltage and multiplying the resulting value by the input voltage, and generates a switching signal for performing on/off control of a switching elementby comparing the current command thus calculated with the input current detected by the input current detector circuit

Power supply and method for generating switching signal for turning on/off switching element of converter unit constituting power supply

A terminal connecting device has a plurality of movable contacts which are biased toward each other by springs to an extent limited by a spacer carried by the frame. The device is easily assembly by fitting shafts through bores in the contacts and using spring holders inserted between pairs of contacts and locked by wedges to exert a biasing force urging opposed contacts together. The shafts are held by support and frame members having open recesses, as opposed to bores, therein.

Terminal connecting device for pulling-type breaker

The disclosure describes an air circuit breaker including a compression coil; a second spring holder to compress the compression coil in the axial direction thereof; and a first spring holder which is subjected to the compression force of the compression coil, the second spring holder being constructed in such a manner that it is formed of a plate material in a rectangular shape, a pair of projected pieces are provided on both sides of the plate material, and a pin is held to pass between the pair of projected pieces in the direction of thickness of the plate so as to be able to support one end of the energy accumulating spring at four points with the pair of projected pieces and the pin in a compressible manner. After compression of the energy accumulating spring by pressure application thereto, its pressure application is released to stretch the energy accumulating spring so as to close a pair of contact points through the first and second spring holders.

Air circuit breaker

A drawer-type circuit breaker of the type adapted to be disposed in an engaged and disengaged position within a housing and a disengaged position outside the housing on extendable support rails is provided with latches which will prevent the extension of the guide rails until the circuit breaker is moved from the engaged position to the disengaged position within the housing. The movement of the circuit breaker to the disengaged position operates the latches to permit extension of the support rails while still preventing movement of the circuit breaker onto the support rails. Movement of the support rails to the fully extended position allows the latches to be released by movement of the circuit breaker to allow the circuit breaker to be withdrawn out of the housing onto the support rails. Actuating levers for engaging and disengaging the circuit breaker are provided on opposite sides of the circuit breaker for movement in respective slots and notches to smoothly and efficiently carry out the engaging and disengaging operation while preventing undesirable vertical movement of the circuit breaker relative to the housing.

Drawer-type circuit breaker

The present invention describes an air circuit breaker including, in combination, a rotational shaft connected with a motor, a cam which rotates in one direction through a ratchet by a handle operation to accumulate energy in an energy accumulating spring for contact closure, an engaging part provided on the outer periphery of the rotational shaft, and a latch which slides on and along the engaging part of the rotational shaft such that the latch means remains disengaged from the engaging part when the cam is rotated by the handle operation so that the rotational shaft remains stationary, and which causes the cam to rotate together with the rotational shaft by engaging the engaging part of the rotational shaft when the rotational shaft is rotated in one and the same direction by the driving motor.

The present invention describes an air circuit breaker having a bounce preventive device which is provided on the direction changing lever interposed between the link mechanism to drive the contact opening and closing mechanism for closure of the contact and the contact opening and closing mechanism, so as to prevent the bouncing phenomenon from occuring at the time of the OFF-operation, thereby making it possible to secure accurate circuit breaking action.

A terminal assembly for a circuit interrupter has a plurality of pairs of metallic spaced parallel flat load terminals with the flat surfaces of the terminals of a pair opposed to each other, the pairs of terminals being positioned side-by-side with spaces therebetween, there being one pair for each phase of the interrupter. Two side walls of insulating material are provided between each side-by-side pair of terminals and abutting each other, and two end walls of insulating material are provided on the outside of the outermost pairs of the terminals. The side walls and end walls have grooves therein holding the side edges of the terminals, the terminals projecting outwardly from between the side walls and end walls. Bolts extend through aligned bolt receiving holes. A plurality of projections are provided at spaced intervals around the holes on the opposite sides of the walls of the grooves, and there are recesses in the walls between adjacent projections, the projections on one abutting wall engaging in the recesses around the corresponding aligned holes of the other abutting wall. A pair of metallic plates are provided over the outer surface of the end walls, the projections on the end walls abutting the plates and spacing the walls and the plates.

Terminal assembly for circuit interrupter

The disclosed terminal assembly for a circuit interrupter comprises three pairs of opposite source and load terminals, each pair being carried on both lateral sides by a pair of first and second side plates by having each lateral side and a recess on that side engaging an associated groove and a raised portion on the front surface of each side plate respectively and connected to adjacent pairs of the opposite source and load terminals through different pairs of the first and second side plates interconnected back to back. All the terminals and side plates are assembled into a unitary structure between two metallic plates by means of bolts and nuts. A supporting strut includes two notches fitted onto the lateral surfaces of end portions of each pair of the opposite source and load terminals and is disposed on each of the side plates. The outermost strut is connected to the adjacent metallic plate trough a lateral locking member and each pair of the intermediate struts are interconnected back to back and connected to the interconnected first and second plates through an intermediate locking member.

An arc-suppressing apparatus for a circuit breaker has a pair of side plates having a plurality of first and second grooves formed therein, the second grooves being shallower than the first grooves and extending linearly from the ends of the first grooves to an end of each of the side plates. The side plates are separated by a spacing strut and loosely connected by a bolt and nut so that a space exists between the plates which is large enough to allow a plurality of grids to slide along the second grooves into the first grooves. Thereafter, the nut and bolt are tightened to firmly secure the grids in the first grooves.

Growing community of inventors

Fukuyama, Japan

Kiyoshi Eguchi