Indonesian Journal of Electrical Engineering and Computer Science Vol. 2, No. 3, June 2016, pp. 583 ~ 591 DOI: 10.11591/ijeecs.v2.i3.pp583-591  583 Received February 15, 2016; Revised May 3, 2016; Accepted May 16, 2016 A Review on Back-to-Back Converters in Permanent Magnet Synchronous Generator based Wind Energy Conversion System Karthikrajan Senthilnathan*, K Iyswarya Annapoorani VIT University, Chennai, India *Corresponding author, e-mail: karthikrajan.s2014phd1147@vit.ac.in Abstract This paper presents a review on the application of back-to-back converters in the field of permanent magnet synchronous generator (PMSG)-based wind energy conversion systems (WECS). The wide applications of the back-to-back converters are power conditioning devices, micro grid, high voltage direct current (HVDC), and renewable energy systems. The intention is to present an overview about the design considerations taken by various researchers in back-to-back converters in the field of WECS and recent developments on it. Generally the configuration of back-to-back converters used are 12 pulse voltage source converters (VSC), 12 pulse current source converter (CSC), and nine (9) pulse voltage source converter. Keywords: back-to-back converter, voltage source converters (VSC), current source converters (CSC), permanent magnet synchronous generator (PMSG), wind energy conversion systems (WECS) Copyright © 2016 Institute of Advanced Engineering and Science. All rights reserved. 1. Introduction The applications of power electronics devices in the field of power systems are making a great impact for power conditioning [1-4], HVDC, Renewable energy systems [5], [6-9], and Micro Grid integrations to the power grid. The impact of back-to-back converters in the field of power systems made the system more reliable and made a way to synchronize the renewable energy sources to the grid. The design of back-to-back converters is broadly classified as voltage source converters and current source converters[10-11]. The voltage source converters (VSC) have the common dc link with capacitor and similarly the current source converters (CSC), [12-13] has dc link with the inductor. The both VSC and CSC have its own advantages and disadvantages. Depends on the requirement of the system, the converter source type and design configuration is chosen by various researchers in this field. The most common design, configuration employed is 12 pulse VSC and CSC based back-to-back converters, 12 pulse VSC based back-to-back converters supported by DC to DC converter with ultra-capacitor connected across the DC link, 9 pulse VSC based back-to-back converter. The design constraint, while implementing the back-to-back converters is to maintain the constant DC link voltage. The base model for the development of the back-to-back converter is a 3 phase diode rectifier connected to the 6 pulse VSC inverter. Based on this model the researchers done an extensive research and modeled the efficient back-to-back converter designs. 2. Classification of Back-to-Back Converter The back-to-back converter is classified, based on the converter type and design aspects used by various researchers in the field of power systems. The Figure 1 shows the classification of the back-to-back converter.