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.

Synchronous rectifier controller for power supply systems with high power switch and high efficiency

Abstract: The present invention discloses an AC-to-DC converter that includes a transformer having a primary side for inputting an input signal and a secondary side for outputting an output signal. The AC-to-DC converter further includes a synchronous rectifier controller connected to the secondary side for controlling a synchronous rectifier (SR) switch on the secondary side for generating the output signal. The SR switch is implemented as a MOSFET transistor with a gate connected to the synchronous rectifier controller. The synchronous rectifier controller further includes a plurality of circuit elements for turning off the SR switch before a main switch of the transformer is turned on. The synchronous rectifier controller further turns on the SR switch when the main switch of the transformer is turned off. The synchronous rectifier controller controls the SR switch and turns it off with a precisely controlled dead time before the main switch of the transformer is turned on.

A Three-Phase Delta Switch Rectifier for More Electric Aircraft Applications Employing a Novel PWM Current Control Concept

Abstract: In the course of the More Electric Aircraft program active three-phase rectifiers in the power range of 5 kW are required. A comparison with other rectifier topologies shows that the three-phase ?-switch rectifier (comprising three ?-connected bidirectional switches) is well suited for this application. The system is analyzed using space vector calculus and a novel PWM current controller concept is presented, where all three phases are controlled simultaneously; the analysis shows that the proposed concept yields optimized switching sequences. To facilitate the rectifier design, analytical relationships for calculating the power components average and rms current ratings are derived. Furthermore, a laboratory prototype with an output power of 5 kW is realized. Measurements taken from this prototype confirm the operation of the proposed current controller. Finally, initial EMI-measurements of the system are also presented.

Voltage sensorless control of the three-level three-switch Vienna rectifier with programmable input power factor

Abstract: The three-level, three-switch Vienna rectifier is fast emerging as the preferred topology for the high-power factor front end converter in many applications Conventional control algorithms for the Vienna rectifier requires sensing of both the supply voltage and the line current However, in many applications, where an electrical generator feeds the rectifier, the ‘supply voltage’ is not available for measurement Even for grid-connected applications the supply voltage may contain significant harmonic distortion which, in turn, increases the harmonic distortion of the rectifier input current To mitigate these disadvantages, this study presents a novel voltage sensorless control algorithm for the Vienna rectifier Voltage sensorless control algorithms reported in the literature for this rectifier, so far permit only unity rectifier terminal power factor operation In contrast, the proposed control algorithm can operate the rectifier at programmable power factor For the verification of the algorithm, experiments were conducted on a laboratory prototype of the Vienna rectifier using both voltage sensorless and sensor-based control algorithms Performances of both these algorithms were found to be similar under transient conditions The voltage sensorless controller achieved better input line current total harmonic distortion in steady state

A novel simplified space-vector-modulated control scheme for three-phase switch-mode rectifier

Abstract: A novel simplified control scheme for a three-phase switch-mode rectifier is proposed in this paper The proposed control scheme is based upon a load-conductance rectifier controller, in which reference current signals are obtained The goal to follow the reference current is converted to follow a reference voltage A simplified control scheme utilizing space-vector modulation is developed to calculate the duty ratio required to synthesize the reference voltage The proposed scheme has the advantage of space-vector modulation with fast dynamic response and is simple enough to be implemented in a single-chip microprocessor 80196MC

High voltage generator for a television receiver

Abstract: A high voltage generator comprising a high voltage generating transformer having a primary winding and first and second secondary windings, a first rectifier having one end connected to one end of the first secondary winding, a capacitor connected to the other end of the first rectifier and adapted to be charged with the voltage appearing at the other end of the first rectifier, a second rectifier connected between the connection point between said first rectifier and said capacitor and one end of the second secondary winding, and a third rectifier for high voltage rectification connected to the other end of the second secondary winding. With this construction variation of the output high voltage with change in load current can be reduced.