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.

Development of a New Permanent-Magnet BLDC Generator Using 12-Phase Half-Wave Rectifier

Abstract: Six-phase double-star armature windings of a synchronous generator are essentially equivalent to 12-phase symmetrical windings displaced in turn by 30deg. This paper proposes and implements a new permanent-magnet brushless dc (BLDC) generator using 12-phase half-wave rectifier. Characteristic of output voltage is analyzed according to the star graph of slot potential, and the design constraints of armature windings are provided. Simulation models of 12-phase synchronous generator with half-wave rectifier and double-star synchronous generator with bridge rectifier are established separately. Field-circuit-coupled analysis is accomplished, and conducted modes of rectified diodes and output characteristic are obtained. It is shown that the current stress of diodes in 12-phase rectification system is less than half of that in double-star rectification system, and the output voltage fluctuation between the two different rectification systems is similar. Experimental results on prototype machine, which agree well with the simulation analysis, also verify the feature of the proposed BLDC generator system.

A Novel Versatile Precision Full-Wave Rectifier

Abstract: In this paper, we have proposed and realized a novel precision full-wave rectifier using an all-pass filter as a 90° phase shifter. The circuit gives a dc output voltage that is almost the same as the peak input voltage over a frequency range of 50 Hz-1 MHz with a very low ripple voltage and low harmonic distortion. Oscilloscope traces of the rectified waveform for the proposed circuit show a ripple voltage of 12 mV obtained with an input voltage of amplitude 1 V and frequency 100 kHz.

X-ray diagnostic generator

Abstract: An inverter, with a frequency lying in the medium frequency range, and a mains rectifier are connected with the high-voltage transformer Between the X-ray tube and the high voltage transformer there is disposed a high-voltage rectifier with a high-voltage filter member There is likewise connected with the filament transformer an inverter with a frequency lying in the medium frequency range and a mains rectifier Filter members are connected between the mains rectifiers and the inverters Plural inverters with different phase may supply respective high voltage transformers, and each transformer may have a voltage doubler high voltage rectifier contributing to X-ray tube anode voltage

High cell density power rectifier

Abstract: A power rectifier having low on resistance, fast recovery times and very low forward voltage drop. In a preferred embodiment, the present invention provides a power rectifier device employing a vertical device structure, i.e., with current flow between the major surfaces of the discrete device. The device employs a large number of parallel connected cells (26), each comprising a MOSFET structure (10) with a gate to drain short via a common metallization (14). A self aligned body implant (24) and a shallow silicide drain contact region (14) integrated with a metal silicide drain contact define a narrow channel region (16) and allow very high cell density. This provides a low Vf path through the channel regions (16) of the MOSFET cells to the contact (12) on the other side of the integrated circuit. The present invention further provides a method for manufacturing a rectifier device which provides the above desirable device characteristics in a repeatable manner. Also, only two masking steps are required, reducing processing costs.

New Multi-Phase Diode Rectifier Average Models for AC and DC Power System Studies

Abstract: More power semiconductors are applying to the aircraft power system to make the system smaller, lighter and more reliable. Average models provide a good solution to system simulation and can also serve as the basis to derive the small signal model for system-level study using linear control theory. A new average modeling approach for three-phase and nine-phase diode rectifiers with improved ac and dc dynamics is proposed in this dissertation. The key assumption is to model the load current using its first-order Taylor Series expansion throughout the entire averaging time span. A thorough comparison in the time domain is given of this model and two additional average models that were developed based on different load current assumptions, using the detailed switching models as the benchmark. The proposed average model is further verified by experimental results. In the frequency domain, the output impedance of a nine-phase diode rectifier is derived, and the sampling effect in the average model is investigated by Fourier analysis.