Voltage regulator

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

Electronic circuit for driving a diode load

Abstract: An electronic circuit includes circuit portions for identifying a largest voltage drop through one of a plurality of series connected diode strings and for controlling a boost switching regulator according to the largest voltage drop. The electronic circuit can sense an open circuit series connected diode string, which would otherwise have the largest voltage drop, and can disconnect that open circuit series connected diode string from control of the boost switching regulator. Another electronic circuit includes a current limiting circuit coupled to or within a boost switching regulator and configured to operate with a diode load. Another electronic circuit includes a pulse width modulation circuit configured to dim a series connected string of light emitting diodes.

Two-stage voltage regulator for laptop computer CPUs and the corresponding advanced control schemes to improve light-load performance

Abstract: This paper presents a two-stage voltage regulator (VR) for the laptop computer CPUs. The advanced control schemes to improve light-load efficiency are also discussed. The test results show that the two-stage solution achieves higher efficiency than the single-stage solution over a wide load range under the entire input voltage range. It is a promising solution for future laptop VRs.

Boost-input backed-up uninterruptible power supply

Abstract: A boost-input backed-up uninterrupted power supply provides an uninterrupted output voltage to a load. The backed-up power supply has an input rectifier and filter for converting an input voltage source voltage into at least an unregulated positive dc voltage source, and an unregulated negative dc voltage source. Batteries provide respective positive and negative battery voltages at corresponding positive and negative battery output terminals. A diode isolates the unregulated positive and negative dc voltage sources from their respective battery voltages for unregulated voltage source values equal to or greater than their respective battery voltages and clamps the unregulated dc voltage values to their respective battery voltages in response to loss of the sinusoidal input voltage source. A pair of boost regulators receives power from the unregulated positive and negative dc voltage sources and provide positive and a negative regulated dc voltage with respect to the return. A dc-to-ac converter receives a reference signal and converts the positive and negative regulated dc voltage into a first uninterrupted output voltage for application to the load. The uninterrupted output voltage is continuously sampled and scaled to provide an output voltage sense signal. The output voltage sense signal is combined with the reference signal to provide an amplified error signal. The dc-to-ac converter is further characterized to continuously adjust and scale the output voltage in amplitude and phase to minimize the amplified error signal.

Distribution voltage control considering the impact of PV generation on tap changers and autonomous regulators

Abstract: The uptake of variable megawatts from photovoltaics(PV) challenges distribution system operation. The primary problem is significant voltage rise in the feeder that forces existing voltage control devices such as on-load tap-changers and line voltage regulators to operate continuously. The consequence is the deterioration of the operating life of the voltage control mechanism. Also, conventional non-coordinated reactive power control can result in the operation of the line regulator at its control limit (runaway condition). This paper proposes an optimal reactive power coordination strategy based on the load and irradiance forecast. The objective is to minimize the number of tap operations so as not to reduce the operating life of the tap control mechanism and avoid runaway. The proposed objective is achieved by coordinating various reactive power control options in the distribution network while satisfying constraints such as maximum power point tracking of PV and voltage limits of the feeder. The option of voltage support from PV plant is also considered. The problem is formulated as constrained optimization and solved through the interior point technique. The effectiveness of the approach is demonstrated in a realistic distribution network model.