Three-phase

About: Three-phase is a research topic. Over the lifetime, 16801 publications have been published within this topic receiving 159477 citations.

Modified SVPWM-Controlled Three-Port Three-Phase AC–DC Converters With Reduced Power Conversion Stages for Wide Voltage Range Applications

Abstract: Three-port three-phase rectifiers (TPTPRs) are proposed by introducing a new low-voltage (LV) dc power port into the three-phase six-switch boost rectifier. An ac input port, an LV dc load port, and a high-voltage (HV) dc bus port are provided simultaneously by TPTPRs. A dc load, whose voltage is lower than the peak amplitude of the ac line voltage and varies over a wide range, can be connected to the LV dc load port of the TPTPR directly. A modified space vector pulse width modulation (SVPWM) strategy is proposed for the TPTPR to accomplish voltage and current regulations, based on which part of the ac input power can be directly fed to the LV dc load within single power conversion stage. As a result, the power rating and losses of the downstream dc–dc converter, which is connected to the HV dc bus port of the TPTPR, are reduced significantly. The conversion efficiency of the TPTPR-based ac–dc converter benefits not only from the reduced power conversion stages, but also from the reduced switching losses due to the multilevel characteristics of the TPTPR. Operation principles and characteristics of the proposed TPTPRs and modified SVPWM strategies are analyzed in detail and verified with experimental results.

Differential mode EMC input filter design for three-phase AC-DC-AC sparse matrix PWM converters

Abstract: The design of a differential-mode EMC input filter for a three-phase AC-DC-AC very sparse matrix converter intended for electrical machine drive applications is discussed in this paper. A review of the steps to be performed in the course of the filter design is presented and a detailed mathematical model of the EMI test receiver for quasipeak measurement of conducted emissions in the frequency range of 0.15...30 MHz is established. Furthermore, formulas for the estimation of the quasipeak detector output based on the LISN output voltage spectrum are provided. As experimentally verified by using a novel three-phase CM/DM separator this procedure allows an accurate prediction of the converter differential mode conducted emission levels and therefore could be employed in the design process for ensuring compliance to relevant EMC standards.

Pinned mid-points multilevel inverter (PMP): Three-phase topology with high voltage levels and one bidirectional switch

Abstract: High power applications need high efficiency devices to produce lower power losses and harmonics while meeting the limitation of voltage and current. Multilevel inverters generate smoother and higher voltage at the output with lower harmonics. They can deliver high power while using medium-voltage switches. In this paper a Pinned Mid-Points (PMP) multilevel inverter topology is introduced and studied which is derived from a Bidirectional Neutral Point Clamped (BNPC) three-level inverter. The proposed PMP multilevel inverter has fewer switches and clamping diodes than the Cascaded H-bridge (CHB) and Neutral Point Clamped (NPC) inverters, moreover it has less bidirectional switches in comparison with the BNPC. Moreover, it can be extended to three-phase inverter same as a NPC only using three legs and common DC link. A five-level inverter using proposed topology is validated by Matlab/SimPowerSystems. It shows the appropriate results of voltage and current as well as their THD%.

A Novel Absolute Value Logic SPWM Control Strategy Based on De-Re-Coupling Idea for High Frequency Link Matrix Rectifier

Abstract: Matrix Rectifier has evolved from the traditional three phase to three phase Matrix Converter (MC) in recent years, and inherits merits of the traditional MC. Matrix Rectifier could be divided into isolated and non-isolated two types according to using high frequency transformer or not. A kind of isolated Matrix Rectifier topology, i.e., high frequency link Matrix Rectifier (HFLMR) has been selected as the study project. Space vector modulation is the mostly focused control strategy for the HFLMR, however its algorithm and its implementation are complicated and difficulty. So a novel straightforward absolute value logic SPWM control strategy based on De-Re-coupling idea has been proposed in this paper, which could realize unit power factor and DC voltage output, and made the transformer gain volt-second balance in a high frequency switching cycle. The validity and feasibility of the proposed control strategy have been well proved by the simulation and experiment results, and a special working phenomenon named as “the dual voltage endemism” has been analyzed in detail.

Non-interruptible power supply systems

Abstract: A non-interruptible power system (NIPS) for generating polyphase A.C. of a substantially constant desired frequency and a substantially constant selected voltage, comprising: (A) a source of interruptible power and a motor energized thereby, (B) a novel generator for producing the desired polyphase A.C. driven by the motor, the generator comprising a plurality of field cores each having a cylindrical surface with a layer of magnetizable permanent magnetic material thereon, cooperatively juxtaposed wound stators each with an excitation coil therein for magnetizing an adjacent layer of permanent magnetic material into a pattern of magnetic poles and at a high remanent flux density, modifying windings for changing the remanent flux density in such pole pattern, supplementing windings for energizing the excitation coil, and primary potential generating windings in slots in the stator, a source of exciter current, and electrical control means for the generator, (C) the generator producing the desired substantially constant frequency A.C. at the desired voltage regardless of variations in the motor speed and even for a brief period of time when the source of power to the motor is interrupted by converting a part of its rotational energy to A.C. output, and leading windings, alone, or with lagging windings, in each of the wound stators having the primary windings, the leading and lagging windings being placed in such positions that, in a three-stator generator, they will each generate a single phase A.C. potential from about 110° to 115° out of phase with the single phase A.C. generated by the primary windings in the same stator, but the A.C. potentials of the leading windings and lagging windings of one stator will each be synchronous with the single phase A.C. potential developed in the other stators' primary windings, thereby obtaining three phase A.C. having a low total harmonic distortion.