Abstract: A rotary transformer includes a shaft, a stator, and a rotor. The stator has a pole surface extending about the shaft. The rotor has a pole surface and operatively connects to the shaft for common rotation with the shaft such that the pole surface of the rotor axially opposes the pole surface of the rotor at an overlap area. The overlap are between the pole surfaces is greater at a first rotor position that at a second rotor position for superimposing a signal indicative of rotor position on electrical power transferred between the stator and rotor.

Abstract: An exemplary electromagnetic induction switch includes a coil, a magnet suspended in the coil, a rectification circuit, and a relay-switch. The coil is connected between two input terminals of the rectification circuit. Two output terminals of the rectification circuit are respectively connected to two relay leads of the relay-switch. One of two switch leads of the relay-switch is connected to a working circuit, and another one of the switch leads of the relay-switch is connected to the working circuit via a power source, thereby controlling the power source supplying power to the working circuit.

Abstract: Provided is an apparatus and method for providing a voltage reduction for single-phase voltage regulator operation in a three-phase power system. The voltage regulator includes a plurality of tap positions selectable to adjust a voltage at a load to an in-band area. The method includes determining a measured voltage and current at the voltage regulator, determining a line voltage drop between the voltage regulator and the load if the measured voltage in the OOB area above the in-band area, and utilizing the measured voltage to lower the voltage at the load if there are no available taps. The method also includes utilizing the measured voltage less the line voltage drop to determine the tap change if there are available taps.

Abstract: A voltage converter includes a transformer circuit, a filter, and a controller. The transformer circuit is coupled to the filter, and the controller is coupled to the transformer circuit and the filter. The transformer circuit includes an input port and an autotransformer coupled to the input port. The voltage converter receives an input signal at the input port and generates a transformer output signal from a transformer output port. The filter receives the transformer output signal on a filter input port and the filter generates an output signal at an output port. The controller receives the output signal from the filter and provides one or more control signals to the transformer circuit to control the output signal.

Abstract: Under load tapchanging voltage regulators with source and load connections, series and shunt transformers, switching devices for causing selectable levels of electric power to flow in either direction between the series and shunt transformers, and tapchanger controls for sensing the voltage at said load connections and causing the switching devices to select proper electric power flows so as to maintain desired voltages at the load connections.

Abstract: The electrical machine, especially a three-phase generator, has a stationary stator (21); a rotatable rotor having an excitation coil (28), a rotary transformer (29) having a primary winding (30) and a secondary winding (31) on respective soft ferrite cores and magnetically coupled with each other via an air gap (38) and a control circuit (40) for loading the primary winding (30) of the rotary transformer (29) with an alternating current. The control circuit (40) includes an input-side current limiting circuit (46), whereby an integrated temperature control is obtained in cooperation with the soft ferrite cores of the primary and secondary windings according to the Curie effect.

Abstract: The invention includes an energy dimmer drive and energy pilot that controls the amount of current and voltage conveyed from an input to a load, based on values selected by the user. The current and voltage is varied by controlling the spacing between the primary and secondary winding of a variable transformer, as well as the movement of a core in the transformer through a minicomputer, relay cards and/or transistors, sensors and readers. The electric energy power variation is continuous, always rephased according to pre-established values and without microswitches, and is controlled instantaneously.

Abstract: The invention comprises an energy dimmer drive and energy pilot that controls the amount of current and voltage conveyed from an input to a load, based on values selected by the user. The current and voltage is varied by controlling the spacing between the primary and secondary winding of a variable transformer, as well as the movement of a core in the transformer through a minicomputer, relay cards and/or transistors, sensors and readers. The electric energy power variation is continuous, always rephased according to pre-established values and without microswitches, and is controlled instantaneously.

Abstract: A microrelay including a substrate having a pair of fixed contacts fixed on a surface thereof and a movable section having a pair of movable contacts opposed to the pair of fixed contacts. The movable section includes a frame for fixing the movable section to the substrate; a movable body having the pair of movable contacts and a pair of magnetic bodies; and a coupling section for pivotally supporting the movable body to the frame. The substrate has a pair of magnetic force generating devices for supplying the pair of magnetic bodies with a magnetic force, thereby selectively causing contact between one of the pair of movable contacts and the fixed contact opposed to the one of the pair of movable contacts; and a magnetic force controlling device for applying the magnetic force generated by each of the pair of magnetic force generating devices only to the magnetic body corresponding to each of the magnetic force generating device.

Abstract: A monolithic interface circuit for use with a linear variable differential transformer (LVDT) position transducer. The interface circuit includes a drive circuit for providing an excitation signal of selectable frequency and amplitude to the LVDT primary winding. The interface circuit further includes a decoder responsive to signals induced in the LVDT secondary windings for computing the position p of the LVDT core as a solution to the equation p=K(A-B)/(A+B), where A and B represent the signals induced in the primary winding and K is a constant scale factor. The decoder includes circuitry for rectifying and filtering the secondary signals, a charge balance loop responsive to the detected signals for providing a binary signal having a duty cycle representative of B/(A+B), and an output circuit responsive to the binary signal for providing the position output. The decoder provides excellent scale factor stability and linearity and is relatively insensitive to variations in primary drive amplitude.

Abstract: A circuit and a process for converting the output signal from a half bridge transducer to that from an LVDT transducer to enable direct use of either signal in an electronic column. The circuit subtracts the transducer exciting signal from a half bridge transducer output signal according to a formula to provide the conversion. A movable jumper allows the circuit to alternatively operate as a unity gain follower to pass an LVDT transducer output signal unchanged.

Abstract: Between two units which are separately arranged, a power source signal is supplied from one of the two units to the other unit via electromagnetic induction coupling by using induction coils, and data signals are mutually transmitted and received between both of the units. A change in coupling distance between the induction coils provided for the two units is detected from a signal level of a reception signal from the unit which receives the power supply. When the reception signal level decreases, the signal level of the power supply signal is increased.

Abstract: A monlithic interface circuit for use with a linear variable differential transformer (LVDT) position transducer. The interface circuit includes a drive circuit for providing an excitation signal of selectable frequency and amplitude to the LVDT primary winding. The interface circuit further includes a decoder responsive to signals induced in the LVDT secondary windings for computing the position p of the LVDT core as a solution to the equation p=K(A-B)/(A+B), where A and B represent the signals induced in the primary winding and K is a constant scale factor. The decoder includes circuitry for rectifying and filtering the secondary signals, a charge balance loop responsive to the detected signals for providing a binary signal having a duty cycle representative of B/(A+B), and an output circuit responsive to the binary signal for providing the position output. The decoder provides excellent scale factor stability and linearity and is relatively insensitive to variations in primary drive amplitude.

Abstract: A signal conditioner for a linear variable differential transformer having a first amplifier which senses the differences in amplitude between secondary alternating current voltages in the two secondaries respectively, and a second amplifier which compares the phase of the difference signal from the first amplifier with the phase of one of the secondary alternating voltages. A conditioned signal A.sub.out is output by the signal conditioner according to the equation A.sub.out =K.sub.1 V.sub.s1 +K.sub.2 (V.sub.s1 -V.sub.s2) where K.sub.1 and K.sub.2 are constants, and V.sub.s1 and V.sub.s2 are instantaneous voltages across the respective secondaries.

Abstract: A system for automatically controlling output voltage to correct for varying input voltage utilizes a transformer having a movable core structure. The output voltage from the transformer is sensed and made to conform to a predetermined standard by moving the movable core structure, which is then locked in position after its adjustment. Voltage changes are step-free, and linear voltage control with respect to time is achieved through non-linear movement of the core structure over a range of variation of the output voltage.