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This paper presents an improved analysis of a novel Programmable Power-factor-corrected-Based Hybrid Muitipulse Power Rectifier (PFC-HMPR) for utility interface of power electronic converters. The proposed hybrid multipuise rectifier is composed of an ordinary three-phase six-pulse diode-bridge rectifier (Graetz bridge) with a parallel connection of single-phase switched converters in each three-phase rectifier leg. In this paper, the authors present a complete discussion about the controlled rectifiers' power contribution and also a complete analysis concerning the total harmonic distortion of current that can be achieved when the proposed converter operates as a conventional 12-pulse rectifier. The mathematical analysis presented in this paper corroborate, with detailed equations, the experimental results of two 6-kW prototypes implemented in a laboratory. Index Terms--AC motor drives, high power drives for trolley-bus systems, high power factor three-phase rectifiers, multipulse rectifiers, tractions applications, 12-pulse rectifiers.

This paper presents a state equation model of a single-phase pulsewidth modulation inverter connected to the grid, using frequency–active power and voltage–reactive power droops, including an extra phase shift loop. The influence of the control parameters on the system's behavior can be studied using the proposed state equation model, which was obtained from the small-signal analysis. The model's results are compared with numerical simulations of the nonlinear system to verify their accuracy. Comparisons are also made with experimental data reported in the literature. [ABSTRACT FROM PUBLISHER]

A novel hybrid three-phase rectifier is proposed. It is capable to achieve high input power factor (PF) and low total harmonic input currents distortion (THDI). The proposed hybrid high power rectifier is composed by a standard three-phase six-pulse diode rectifier (Graetz bridge) with a parallel connection of single-phase Sepic rectifiers in each three-phase rectifier leg. Such topology results in a structure capable of programming the input current waveform and providing conditions for obtaining high input power factor and low harmonic current distortion. In order to validate the proposed hybrid rectifier, this work describes its principles, with detailed operation, simulation, experimental results, and discussions on power rating of the required Sepic converters as related to the desired total harmonic current distortion. It is demonstrated that only a fraction of the output power is processed through the Sepic converters, making the proposed solution economically viable for very high power installations, with fast investment payback. Moreover, retrofitting to existing installations is also feasible since the parallel path can be easily controlled by integration with the existing dc-link. A prototype has been implemented in the laboratory and it was fully demonstrated to both operate with excellent performance and be feasibly implemented in higher power applications. [ABSTRACT FROM AUTHOR]