Voltage regulator

About: Voltage regulator is a research topic. Over the lifetime, 33536 publications have been published within this topic receiving 350859 citations.

Investigation of topology candidates for 48 V VRM

Abstract: In future applications, it will be impractical for voltage regulator modules (VRMs) to draw power from the 12 V output of the silver box because the voltage bus will be too low to deliver more power. Therefore, distributed power systems (DPSs) with buses of 48 V will be more feasible solutions for future high-end PCs. This paper focuses primarily on the investigation and comparison of 48 V VRM candidates. Six 48 V VRM prototypes are built and compared: the active clamp forward, asymmetrical half bridge, symmetrical half bridge, push-pull, push-pull forward and integrated-filter push-pull forward topologies.

Real-time task scheduling for a variable voltage processor

Abstract: This paper presents a real-time task scheduling technique with a variable voltage processor which can vary its supply voltage dynamically. Using such a processor, running tasks with a low supply voltage leads to drastic power reduction. However, reducing the supply voltage may violate real-time constraints. In this paper, we propose a scheduling technique which simultaneously assigns both CPU time and a supply voltage to each task so as to minimize total energy consumption while satisfying all real-time constraints. Experimental results demonstrate effectiveness of the proposed technique.

Multiple winding multiple voltage alternator electrical supply system

Abstract: A multiple voltage electrical supply system continuously connected for individually charging a plurality of battery supplies continuously connected in series with one another to supply a plurality of load circuits having differing d.c. input voltage requirements and, typically, also having differing expected electrical power consumption rates. The system includes an alternator having electrically isolated generating windings disposed so as to insure that the magnetic flux linking each of the generating windings bears a substantially constant ratio to that linking the other of the generating windings. The exemplary embodiment has generating windings of different characteristic resistance per unit length such that there is an increased internal voltage drop in the winding intended to supply the lighter electrical load. The resultant voltage regulation characteristics are such that a single voltage regulator is sufficient to maintain both of the output voltages at a substantially constant predetermined ratio.

Semiconductor integrated circuit including voltage converter effective at low operational voltages

Abstract: A push-pull type output circuit is used in the differential amplifier of a voltage converter circuit. The threshold voltage of the driving transistor is set lower than the voltages of the transistors of the other circuits to operate the differential amplifier at a voltage higher than the power supply voltage. By using the push-pull type output circuit, the amplitude increases and it is possible to raise the capacity of the driving transistor. Moreover, by setting the threshold voltage of the driving transistor of the buffering circuit lower than the threshold voltages of the transistors of the other circuits, it is possible to further raise the driving capacity. Increase of the sub-threshold current due to lowering of the threshold voltage can be prevented by operating the differential amplifier at a voltage higher than the power supply voltage.

An approach to harmonic current-free AC/DC power conversion for large industrial loads: the integration of a series active filter with a double-series diode rectifier

Abstract: This paper proposes a new harmonic-free AC/DC power converter characterized by the integration of a small-rated series active filter with a large-rated double-series diode rectifier. The DC terminals of the series active filter are directly connected in parallel with those of the double-series diode rectifier, thereby forming a common DC bus. The series active filter enables the diode rectifier to draw three-phase sinusoidal currents from the utility. In addition, it can provide the supplementary value-added function of regulating the common DC bus voltage to a limited extent of /spl plusmn/5%, with slightly increased RMS voltage rating but without increasing peak voltage rating. Experimental results obtained from a 5 kW laboratory system verify the practical viability and cost-effectiveness of the proposed AC/DC power converter.