Abstract: A power output control module for power distribution is installed inside a power distributor that is connected to an AC power source and multiple electronic devices to control the AC power outputted to the electronic devices. The power output control module continuously detects whether the AC power inputted is normal. When the AC power source is disconnected by accident, a latch relay is controlled to switch to be open, so that the AC power source and the electronic devices are disconnected. This prevents the instantaneous surge current from damaging the electronic devices when the AC power source resumes its normal output and also increases the safety and reliability of electronic devices.

Abstract: A electromagnetic device may include a core in which a magnetic flux is generable and an opening through the core. A primary conductor winding may be received in the opening and extend through the core. A primary electrical current signal flowing through the primary conductor winding generates a magnetic field about the primary conductor winding and a first magnetic flux flow in the core. A secondary conductor winding may be received in the opening and extend through the core. A first modular conductor winding may extend through the opening and encircle a first outer core portion of the core. A first modulation signal flowing through the first modular conductor winding modulates the primary electrical current signal to provide a modulated output current signal at an output of the secondary conductor winding.

Abstract: A field device that communicates in accordance with Ethernet signaling is provided. The field device is powered by virtue of its Ethernet connection. The field device preferably includes a feature board that includes an Ethernet network connection and a field device connection. The feature board is configured to power the field device with power received through the Ethernet network connection. The feature board interacts with the field device using a process industry standard communication protocol. A method of operating a field device is also provided.

Abstract: A magnetic component, with a first and a second U/UR core (U1, U2) assembled to a first O-shaped core assembly, wherein an U/UR core has—according to its shape—a first post and a second post with free ends on one side and a leg connecting the first post and the second post on their other side, wherein the first and the second U/UR core (U1, U2) are assembled with their free ends abutting each other to form the first O-shaped core assembly. The free ends of a third U/UR core (U3) are abutting the outside of the first O-shaped core assembly on one side and that the free ends of a fourth U/UR core (U4) are abutting the outside of the first O-shaped core assembly on an opposite side. In another embodiment, the leg of a third U/UR core (U3) is abutting the outside of the first O-shaped core assembly, wherein the ends of a fourth U/UR core (U4) are abutting the ends of the third U/UR core (U3). In a further embodiment, the ends of a third U/UR core (U3) are abutting the outside of the first O-shaped core assembly.

Abstract: An example control circuit for use in a power converter includes an input voltage sensor, a current sensor, and a drive signal generator. The input voltage sensor generates a first signal representative of an input voltage (Vin) of the power converter. The current sensor generates a second signal representative of a switch current through a power switch of the power converter. The drive signal generator generates a drive signal to control switching of the power switch in response to the first and second signals. The drive signal generator sets a switching frequency of the drive signal based on a product K×Vin×t to control a maximum output power of the power converter, where K is a fixed number and t is a time it takes the second signal to change between two values of the switch current when the power switch is in an on state.

Abstract: There are provided a power factor correction circuit capable of transferring extra power to a ground before performing switching for a power factor correction to thereby reduce a switching loss generated in switching for a power factor correction, and a power supply device and a motor driving device having the same. The power factor correction circuit includes: a main switch switching input power to adjust a phase difference between a current and a voltage of the input power; and an auxiliary switch switched on before the main switch is switched on, to thereby form a transmission path for extra power of the main switch.

Abstract: An example controller for a power converter includes an input voltage sensor, a current sensor, an oscillator, a timing and multiplier circuit, and a drive signal generator. The input voltage sensor receives an input signal representative of an input voltage and the current sensor senses a current in a power switch. The oscillator generates a signal having a switching frequency and the timing and multiplier circuit adjusts the switching frequency of the signal to be proportional to a value that is the input voltage multiplied by a time it takes the current in the power switch to change between two current values. The drive signal generator drives the power switch into the on state for an on time period and an off state for an off time period in response to the current in the power switch and in response to the signal having the switching frequency.

Abstract: Provided are a method and apparatus for improving the power factor of an input power. The apparatus includes an input unit receiving the input power, a power factor correction unit correcting the power factor of the input power applied to the input unit, and a saturation prevention unit controlling the power factor correction unit such that the corrected power does not exceed a set power limit.

Abstract: A controller for a power converter is disclosed. An example circuit controller according to aspects of the present invention includes an input voltage sensor to be coupled to receive an input signal representative of an input voltage of the power converter. A current sensor is also included and is to be coupled to sense a current flowing in a power switch. A drive signal generator is to be coupled to drive the power switch into an on state for an on time period and an off state for an off time period. The controller is coupled to adjust a duty cycle of the power switch in response to a difference between a time it takes the current flowing in the power switch to change between two current values when the power switch is in the on state and a control time period.

Abstract: A voltage control circuit is disclosed. A power factor corrector may utilize the control circuit to provide power factor correction for an AC induction motor. An AC induction motor system may combine the power factor correct with an AC induction motor.

Abstract: Aspects of the invention are directed to systems and method for limiting losses in an uninterruptible power supply. In one aspect, the present invention provides an uninterruptible power supply (UPS) comprising an input to receive input power having an input voltage, an output to provide output power having an output voltage, a neutral line, an automatic voltage regulation (AVR) transformer coupled to the input and the output of the UPS and having an input, an output, a core and at least one switch controllably coupled to at least one of the core, the input and the output, and a means for isolating the core of the AVR transformer from the neutral line when the input voltage is substantially equal to a defined output voltage.

Abstract: A controller for a power converter is disclosed. An example circuit controller according to aspects of the present invention includes an input voltage sensor to be coupled to receive an input signal representative of an input voltage of the power converter. A current sensor is also included and is to be coupled to sense a current flowing in a power switch. A drive signal generator is to be coupled to drive the power switch into an on state for an on time period and an off state for an off time period. The controller is coupled to adjust a switching cycle period of the power switch to be proportional to a value of the input signal multiplied by a time period. The time period is the time it takes for the current flowing in the power switch to change between two current values when the power switch is in the on state.

Abstract: A controller for a power converter is disclosed. An example circuit controller according to aspects of the present invention includes an input voltage sensor to be coupled to receive an input signal representative of an input voltage of the power converter. A current sensor is also included and is to be coupled to sense a current flowing in a power switch. A drive signal generator is to be coupled to drive the power switch into an on state for an on time period and an off state for an off time period. The controller is coupled to adjust a switching cycle period of the power switch to be proportional to a value of the input signal multiplied by a time period. The time period is the time it takes for the current flowing in the power switch to change between two current values when the power switch is in the on state.

Abstract: A push-pull inverter is supplied from an inductively current-limited DC voltage source by way of a center-tap on a transformer having significant inductance. This transformer inductance is parallel-coupled with a capacitance means. The inverter is made to self-oscillate through positive feedback provided by way of a saturable current transformer. The inverter frequency is determined by the saturation time of this current transformer, which saturation time is designed to be somewhat longer than the half-cycle period of the natural resonance frequency of the transformer inductance combined with the capacitance means. By controlling the length of this saturation time, the magnitude of the current provided to the fluorescent lamp is controlled, thereby permitting control of the light output in response to changes in the magnitude of the power line voltage.

Abstract: An electrical arrangement is disclosed for use in supplying electrical power to the units in a motor vehicle. The arrangement comprises a battery, and an inverter to receive power from the battery and to generate a high frequency signal at an intermediate voltage higher than the voltage of the battery. There is a distribution network to distribute the high frequency signal to the units in the vehicle. At least some of the units supplied with electrical power are provided with step-up transformers to step-up the intermediate voltage to a higher voltage, that higher voltage being used by the units.

Abstract: An operator controllable transformer having a shunt magnetic path with a control coil is provided. The transformer includes phase control circuitry to control the output of the transformer by phase controlling current flow in the shunt coil, thereby controlling the flux through the shunt magnetic path and the flux coupling with the secondary coil. Power for the control circuitry is derived from the current induced in the shunt coil.

Abstract: A transformer having a shunt magnetic path and a shunt coil is provided. The transformer includes control circuitry to control the output of the transformer by controlling current flow in the shunt coil, thereby controlling the flux through the shunt magnetic path and the flux coupling with the secondary coil. The current in the shunt coil is phase-controlled and power for the control circuitry is derived from the current induced in the shunt coil.

Abstract: An AND function gating circuit for A.C. signals comprising several magnetic circuits around a common limb, each circuit having a separate input winding and a single output winding on the common limb. The magnetic flux level in the common limb is greatly increased when all input windings are simultaneously energized by A.C. signals of the same frequency and in phase relative to the output achieved under other input signal conditions.

Abstract: A control system for driving a variable speed AC motor employing a fixed frequency AC power source, combines pulses representative of a desired slip frequency with pulses of a frequency proportional to the speed of the motor. The combined pulses are employed with a speed command signal to set a threshold which determines the fraction of each cycle of the AC primary power which is fed to the motor. In addition, the speed and slip pulses are employed to direct the AC power to specific ones of the windings of the motor to thereby create a rotating magnetic field in the induction motor. An array of silicon-controlled rectifiers does the actual gating and an SCR protect circuit ensures that transfer of control from one SCR to another is inhibited until all current ceases to flow in an SCR being extinguished. A forced commutation circuit forces the extinction of all current remaining in the last conducting SCR feeding a motor winding at the transfer time from that motor winding to the next.

Abstract: A two-part separable inductive coupler is provided in one part with a current-limiting reactor whose control winding is energized by control means in response to the formation of a magnetic circuit between primary and secondary windings incorporated in said one part and the other said part respectively. Said control means may comprise a rectifier connected across said primary winding and is arranged to saturate the reactor when the coupler parts are connected and leave the reactor unsaturated when the parts are separated, so as to limit the primary current.

Abstract: In a method for the enhancement of the A.C. performance of an inductor such as a transformer or choke, the tendency of the core of the inductor to become saturated by flux arising from low frequency A.C. or D.C. currents flowing in the inductor winding is reduced by detecting the magnitude of such currents and applying to a control winding wound on the core of the inductor a compensating current in order to generate a magnetic flux in the core of the inductor which opposes the component of flux tending to cause saturation. An inductor to which the method may be applied may accordingly comprise a main winding, a magnetic core, a control winding, means for sensing the presence in said main winding of a current having a frequency below a predetermined limit, and means for applying to said control winding a control circuit tending to balance the flux generated by the sensed current.

Abstract: A current isolator circuit generates an electrically isolated output current which is related to an input current. The current isolator includes a magnetically saturable transformer having a core and first, second, and third windings. The input current flows through the first winding, and the output current flows through the second winding. The third winding is driven by a periodic drive signal, which alternately drives the transformer between first and second magnetically saturated states. When a change in the input current occurs, the magnetizing current in the third winding changes, thereby causing a change in the time required to drive the transformer from the first to the second magnetically saturated state, and an opposite change in the time required to drive the transformer from the second to the first magnetically saturated state. The difference in saturation times is sensed and is used in controlling the magnitude of the output current flowing through the second winding.

Abstract: An electrical arrangement is disclosed for use in supplying electrical power to the units in a motor vehicle. The arrangement comprises a battery, and an inverter to receive power from the battery and to generate a high frequency signal at an intermediate voltage higher than the voltage of the battery. There is a distribution network to distribute the high frequency signal to the units in the vehicle. At least some of the units supplied with electrical power are provided with step-up transformers to step-up the intermediate voltage to a higher voltage, that higher voltage being used by the units.