Winding Layout Considerations for an Integrated Generator–Rectifier System

Abstract

An integrated generator-rectifier system is a promising architecture to harvest energy in offshore wind turbines. The system processes the majority of the incoming power using reliable, efficient, and inexpensive passive diodes operating at generator line frequency. Elimination of capacitors at the diode rectifiers' output by appropriately phase shifting the voltages of a multiport generator further improves the reliability of the overall architecture. This paper creates a generalized framework to evaluate the interactions among the different generator ports, diode-bridge rectifiers, and the active rectifier that is used to control the power flow. The framework enables quantifying the effect of integration on the dc-bus power ripple and power imbalance among different generator ports. An exemplary winding layout is proposed that ensures theoretically zero interaction between the passive ports though all the ports are mounted on a magnetic structure. A 10 MW integrated generator-rectifier design and simulation proves the accuracy of the framework using coupled circuit-and-finite-element simulation. Finally, a laboratory prototype shows the realization of the winding layout. The proposed inductance-matrix based framework can be used to evaluate other winding layouts to estimate the effect of magnetic coupling on the system's performance.

DC Grid Interface for the Integrated Generator–Rectifier Architecture in Wind Energy Systems

“…A low-power laboratory prototype has been developed to validate the effectiveness of the proposed converter topology and the control strategy. A Samsung DC96-01218D permanent-magnet machine was redesigned and modified to create a three-port generator [33]. Two ports are connected to passive rectifiers and the remaining one to an active rectifier.…”

“…Equations (33,34,35) are used to compute the loss within the generator-side passive rectifiers as a function of ω. The total loss within all the three-phase diode-bridge rectifiers is…”

Design of a High-Performance Control Scheme for a Grid-Connected DFIG‐Based Wind Energy Conversion System Using Model Predictive Control and Hysteresis Model

“…Its harm is to produce a large number of current harmonics and inject them into the grid, thus affecting the quality of power and reducing the service life of electronic equipment. Therefore, in recent years, single-phase PWM rectifiers have been extensively utilised in renewable energy generation [1], [2], motor drive systems, uninterruptible power supplies, and battery energy storage systems. A single-phase PWM rectifier has a higher power factor and lower harmonics compared to an uncontrolled rectifier [3].…”