International Journal of Science and Research (IJSR) ISSN (Online): 2319-7064 Index Copernicus Value (2013): 6.14 | Impact Factor (2015): 6.391 Volume 5 Issue 6, June 2016 www.ijsr.net Licensed Under Creative Commons Attribution CC BY Study of Power Converter Topologies Used for Power Quality Improvement in PMSG Wind Farm Application Anant Deogaonkar 1 , Radharaman Shaha 2 1 Abha Gaikwad Patil College of Engineering, Mohgaon, Nagpur, Maharashtra, India 2 Professor, Abha Gaikwad Patil College of Engineering, Mohgaon, Nagpur, Maharashtra, India Abstract: As a source of green and abundant energy wind power is proposed as one of the main new power sources and is day by day gaining more and more importance. In last few decades, different types of wind turbines are developed to increase the maximum power capture with minimum cost and expansion for use of wind turbine for onshore and offshore applications. This paper focuses on the Power Converter Topologies used for renewable energy resources for wind farm application. In wind energy conversion system four main types of generators used are Squirrel Cage Induction Generator(SCIG) ,Doubly Fed Induction Generator (DFIG) ,Wound Field Synchronous Generator(WFSG) and Permanent Magnet Synchronous Generator (PMSG).PMSG is directly coupled to wind turbine and hence is called as Direct Driven Generator. This paper mainly discusses Power Converter Topologies in use with Permanent Magnet Synchronous Generator. Keywords: Induction generators, Synchronous generators, onshore/offshore wind turbine, power quality, Permanent magnet generators, Power quality, multiple converters, matrix converters, z- source inverter 1. Introduction Wind energy conversion system is an important and popular renewable energy technology over other different renewable energy conversion technologies [1]. Wind energy capacity has grown rapidly over the last decade and has become the fastest grown renewable energy technology [2]. Wind energy is produced by running wind turbine generator in a variable speed mode. Wind turbines are classified with a view to the rational speed, the power regulation, and the generation system. According to the construction of the drive system, the turbines are classified into the geared and the direct drive type [3], [4]. The direct drive system has advantages such as lower cost, smaller size, and weight reduction [5]. Direct drive system like PMSG has many competitive advantages over other direct drive system because of its great energy yield, noise reduction, good reliability and high efficiency [6], [7]. Currently many topologies are used in stand-alone and grid connected wind energy conversion system. 2. Wind Energy Conversion System Blades of the wind turbines designed aerodynamically, they capture power from the wind and convert wind power into the mechanical power [8]. A gear box is used to match the speed of wind turbine and generator. PMSG is a direct-drive type system so it’s used to eliminate the gear box and reduces the size of wind energy conversion system [9]. After converting the mechanical wind energy into electrical energy by the generator, power converters are included for conversions of generated AC power into DC power (either for storing energy in battery or supplying dc power to resistive loads) or in AC/DC/AC system supplying AC power grid coupled systems. Various topologies of converter used with PMSG base wind energy conversion system for high efficiency and low cost [2]. Figure 1: Wind Energy Conversion System for PMSG 3. Power Quality Issues Various power quality issues that normally occur in a power system are listed below a) Voltage Sag  Description: A decrease of the normal voltage level between 10 and 90% of the nominal rms voltage at the power frequency, for durations of 0,5 cycle to 1 minute.  Causes: Faults on the transmission or distribution network (most of the times on parallel feeders). Faults in consumer’s installation. Connection of heavy loads and start-up of large motors.  Consequences: Malfunction of information technology equipment, namely microprocessor-based control systems (PCs, PLCs, ASDs, etc) that may lead to a process stoppage. Tripping of contactors and electromechanical relays. Disconnection and loss of efficiency in electric rotating machines.) b) Very Short Interruptions  Description: Total interruption of electrical supply for duration from few milliseconds to one or two seconds.  Causes: Mainly due to the opening and automatic reclosure of protection devices to decommission a faulty Paper ID: NOV164793 http://dx.doi.org/10.21275/v5i6.NOV164793 2334