Abstract:
Magnetic latches and switches based on the flux cancellation or flux diversion principle use the high coercive force of cobaltrare earth permanent magnets such as cobalt-samarium. These permanent magnets are not demagnetized by a flux cancellation coil and can be made thin in the field direction. Devices with thin magnetic circuits and low volume armature achieve high unlatching speeds.
Abstract:
A solid-state voltage regulator constructed with low current rating step changing solid-state switches, or pairs of switches, is protected against overcurrents in the interval before the opening of a slow-acting circuit breaker. The overcurrent is transferred from one switch to another in sequence rapidly to take advantage of the short time current overcapacity, or is diverted to a shunting protective switch which can have other functions. Alternatively, one switch has a high current rating, and the overcurrent is diverted to the heavy-duty switch.
Abstract:
A polycrystalline varistor of the bulk effect zinc oxide base type adapted for use in voltage surge suppression on VHF signal lines is disclosed. The device comprises a connector having a housing attached thereto containing a polycrystalline varistor and a conductive spring member. The spring member is configured to provide for the proper mechanical positioning of the varistor and to provide an electrical inductance in series with the varistor to prevent capacitive loading of the protected signal line.
Abstract:
When a short circuit or shoot-through occurs in a power circuit having two thyristors in series with commutating circuit inductors, a shunt capacitor isolated from the DC power supply by an impedance automatically resonates with the inductors to turn off both thyristors. A second automatic recovery system for repeated short circuits that occur before the capacitor has recharged operates to temporarily disable the power supply. In a high-voltage inverter the impedance is a resistor functioning to dampen voltage overshoots and to implement a relay or solid state second recovery system.