Precision rectifier

About: Precision rectifier is a research topic. Over the lifetime, 4952 publications have been published within this topic receiving 63668 citations. The topic is also known as: super diode.

Front-end ASIC for a GEM based time projection chamber

Abstract: A time projection chamber for experiments with the laser electron gamma source is being developed. It is composed of a can and a single-ended, dual-stage gas electron multiplier, with associated anode plane pixellated into about 8000 pads. The front-end electronics must provide energy, timing, and address information from those pads involved in measuring each track. For center of gravity determination this information must be sampled from the above-threshold pad and from the two adjacent ones. An efficient scheme for readout of the /spl ap/8000 front-end channels between each measurement cycle is also required. A 32-channel front-end application-specific integrated circuit has been developed to serve this detector. Fabricated in 0.25 /spl mu/m CMOS technology, it dissipates 41 mW. Each channel implements a low noise charge preamplifier with continuous reset of new concept, shaping amplifier with bandgap referenced baseline stabilizer, single threshold discriminator, dual-phase peak detector, timing detector, and logic for neighbor enabling. The readout process is based on token passing and flag.

A high density 48 V 200 A rectifier with power factor correction-an engineering overview

Abstract: In telecommunications installations it is desirable for power equipment to draw a balanced three phase current at unity power factor with zero neutral current. A compact 48 V, 200 A rectifier weighing 32 kg has been commercially developed for this need. The rectifier employs the power conversion techniques first reported at INTELEC 1989 by Dennis Chapman of Swichtec Power Systems (formerly Eltec Electronics), New Zealand. Powered from a three wire, three phase 400 V, 50-60 Hz supply the rectifier presents essentially a unity power factor to the line. The thermal layout adopted, combined with fan cooling, keeps the overall dimensions to 400 mm wide/spl times/178 mm high/spl times/460 mm deep (4U/spl times/19 inch rack module). Maximum continuous output power is 11.2 kW (56 V, 200 A) at an efficiency of 90%. The rectifier comprises three modules. Each module operates at 230 V AC and can supply up to 70 A at 56 V DC. The three modules are connected in a star or 'Y' configuration. The junction point of the three modules is maintained at the equivalent neutral point voltage by controlling the power processed by each module. >

Contactless IC card

Abstract: A contactless IC card having an antenna, a transmit/receive circuit for recovering data (clock) and electric power from a carrier signal received by the antenna, a logic circuit operated with the electric power supplied thereto from the transmit/receive circuit, and a memory. The transmit/receive circuit has a rectifier circuit for outputting data (clock) and rectifier circuits for electric power in such a manner that the carrier signal is inputted to each of the rectifier circuit for outputting data (clock) and the rectifier circuit for electric power. With this configuration, high frequency matching can be optimized separately for the rectifier circuit for outputting data (clock) and the rectifier circuit for electric power. It is also possible to separately optimize adjustments to a voltage of recovered data (clock) and a recovered supply voltage.

A High-Frequency-Link Single-Phase PWM Rectifier

Abstract: This paper proposes a high-performance “cycloconverter-type” high-frequency-link (HFL) single-phase rectifier with an active voltage clamper, which provides bidirectional two-stage galvanic isolation ac-dc power conversion Modulation strategy, modeling method, and control scheme are comprehensively developed for the HFL rectifier to guarantee its superior performances: 1) two-stage power conversion and soft-switching switch devices lead to high conversion efficiency; 2) complete elimination of voltage spikes during commutation ensures safe operation of high-frequency switching devices; and 3) it can equally function as a high-performance conventional Pulsewidth Modulation (PWM) rectifier: sinusoidal input current, constant dc output voltage, bidirectional power flows between dc side and ac side, and adjustable power factor A prototype of the proposed HFL rectifier is built for evaluation The experiment results demonstrate the efficacy of the soft-switching HFL rectifier and its highly promising control performance The proposed rectifier offers a high-efficiency, high-power-density, and high-performance galvanic isolation power conversion solution to extensive applications

Four-step commutation strategy of PWM rectifier of converter without DC link components for induction motor drive

Abstract: In this paper, we describe a method of generating gate signals of the PWM rectifier section of the converter without DC link components, which is able to remove snubber circuits In the snubber circuits, losses have been dissipated every time the switches of the rectifier section are turned on and off The commutation strategy of the proposed method consists of four steps during the switching process The proposed method is verified by experimental tests on an induction motor drive It is concluded that it decreases losses in the rectifier section