Voltage regulator

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

Investigating coupling inductors in the interleaving QSW VRM

Abstract: The multi-channel interleaving quasi-square-wave (QSW) buck converter has been proved to be suitable for the voltage regulator module (VRM) with low voltage, high current and fast transient response. Integrated magnetic is used to reduce the size of the converter and improve efficiency. However, the structure of the integrated magnetic requires precise adjustment. In this paper, analysis shows that a properly designed integrated magnetic can improve the steady-state and dynamic performance without requiring precise adjustment.

Voltage converting circuit and multiphase clock generating circuit used for driving the same

Abstract: A voltage converting circuit of the charge pump step-up type includes a first circuit means for charging each of first and second capacitors with the voltage of a voltage source at a first timing. A second circuit operates to serially connect the charged first capacitor between a positive electrode of the voltage source and a positive voltage output terminal at a second timing so that a positive voltage which is a double of the voltage source voltage, is supplied from positive voltage output terminal. A third circuit operates to the charged first and second capacitors in series between a ground terminal and a negative voltage output terminal at a third timing so that a negative voltage which is a double of the voltage source voltage, is supplied from the negative voltage output terminal. Since the positive voltage and the negative voltage are generated independently of each other, a voltage variation on one of the positive and negative voltage output terminals caused by an external load causes no voltage variation on the other of the positive and negative voltage output terminals.

A simplified maximal power controller for terrestrial photovoltaic panel arrays

Abstract: Perusal of the V-I characteristics of commercial solar panels with insolation, ambient temperature and production spreads as parameter, indicate that the maximum power is obtained from such a panel when it is loaded to a working voltage that is a fixed percentage of its open circuit voltage within (+2)%. This contribution describes a system that uses this characteristic to achieve maximum power control by determining the open circuit voltage and automatically loading the panel to the maximum power point as applied to a battery charging installation. The description includes the application of a novel modified darlington circuit to boost the efficiency of a pulse width controlled switch mode type regulator by reducing the darlington saturation voltage by a compensating voltage. Advanced switching technology is applied to reduce switching losses, and maximise efficiency.

Voltage Dynamics of Current Control Time-Scale in a VSC-Connected Weak Grid

Abstract: Voltage problems are challenging in modern power systems with a high penetration of renewables integrated via power electronics. This paper extends the transient time-scale classification to identify voltage dynamics in modern power systems. Voltage dynamics in the current control time-scale is firstly proposed and then the mechanism of terminal voltage change is elaborated. After that the significant influences of the voltage source converter (VSC), current control (CC) loop and voltage feed forward (VFF) on the voltage dynamics in the current control time-scale are discussed. The VSC current control loop provides positive damping on the terminal voltage, while the VFF scheme results in an additional loop that deteriorates terminal voltage dynamic performance and stability. In addition, a sensitivity analysis was carried out to investigate the influence of critical parameters on stability. Finally, simulation results of a current-controlled VSC attached to different strength of AC grids (including a weak grid) are presented to validate the phenomenon and the influencing factors of voltage dynamics in the current control time-scale.

A voltage reduction technique for digital systems

Abstract: A self-regulating on-chip voltage-reduction circuit that adjusts the internal supply voltage to the lowest value compatible with chip speed requirements is described. Besides enhancing reliability, this technique allows power savings. The technique is based on regulation of the supply voltage of an equivalent critical path, a small circuit with delay V/sub dd/ properties proportional to those of the actual critical path. The output of this equivalent critical path is compared with the output of a second identical equivalent critical path which is connected to the full supply voltage and serves as a reference. In a first-order approximation the ratio of the delay of a critical path to the period of a ring oscillator is a constant that depends only on the number of gates, the dimensions of the transistors, and the load capacitances. This means that a ring oscillator can be used as an equivalent critical path for all digital circuits. Moreover, when the supply voltage of a ring oscillator (VCO) is changed the frequency changes. The voltage regulator principle can be implemented with a phase-locked loop (PLL). By adjusting the VCO supply voltage, the PLL causes the VCO to oscillate at N*f/sub in/. If the dimensions of the VCO transistors and the division ratio N are such that the critical path functions correctly at the regulated voltage, it will always function correctly, as changing parameters temperature or frequency f/sub in/ affect the VCO in the same way as the circuitry. >