Girish B M . Int. Journal of Engineering Research and Application www.ijera.com ISSN : 2248-9622, Vol. 7, Issue 2, ( Part -3) February 2017, pp.41-48 www.ijera.com DOI: 10.9790/9622- 0702034148 41 | Page A New Method of Reference Signal Generation Applied To UPQC-PHEV For Grid Integration of WECS-SCIG Girish B M * , Prof. Anguraja R ** *(PG Scholar, Dept of EEE, DBIT, VTU, Bengaluru. E-mail: girishbm23@gmail.com) ** (Associate Professor, Dept of EEE, DBIT, VTU, Bengaluru. E-mail: angurajaramasamy@gmail.com) ABSTRACT In this paper a new reference signal generation control technique is proposed for integration of Unified Power Quality Conditioner (UPQC) with Plug-in Hybrid Electric Vehicle (PHEV) for overcoming voltage sag and other voltage fault conditions on wind farms which is connected to grid. The interaction of wind generators and grid causes increased short circuit current which leads to instability during fault conditions. The new control technique which generate reference signals for series active power filter (Series APF) and shunt active power filter (Shunt APF) of UPQC by using PHEV as an Energy Storage System (ESS) which will take care of all types of voltage faults occurred in the system and provide energy storage to DC link between Series APF and Shunt APF parts of UPQC. The control scheme proposed also maintains transaction of active and reactive power of Wind Energy Conversion System based on Squirrel Cage Induction Generators (WECS-SCIG) and grid. The fuzzy logic provides fast and dynamic response to clear faults occurred in the system. Keywords: UPQC; Reference signals generation; PHEV; Voltage Sag; Fuzzy Logic Controller; Grid Integration. I. INTRODUCTION In the last few years, large-scale integration of wind energy has become a fact due to social and geopolitical concerns [1]. As the penetration of large scale wind turbines into the electric power grid increases, connection codes are requiring turbines ride through a short-term low or zero voltage event at the point of common coupling (PCC) [2]. In electrical terms, the evolution from short-circuit induction generators and wound rotor induction generators with super synchronous cascade has reached its end with the introduction of doubly fed induction generators (DFIGs, or doubly fed asynchronous generators) with bidirectional and partially rated power inverters[2]. Many wind turbines are connected in weak areas where heavy unsymmetrical loads, unsymmetrical transformer windings, or Transmission impedance and transient faults (voltage dip) will be typical sources of unbalanced operation mode. In this condition DFIG may lead to loss of control due to high power demands for inverters. Presently, variable speed wind turbine generator system (WTGS) is becoming more popular than that of fixed speed Induction generators. The fixed speed wind generator due to their superior characteristics such as brushless and rugged construction, low cost, maintenance free, and operational simplicity, but they require large reactive power to recover the air gap flux when a short circuit fault occurs in the power system [3] unless otherwise the induction generator becomes unstable due to the large difference between electromagnetic and mechanical torques, and then it requires to be disconnected from the power system. A shutdown of large wind farm may have a serious effect on the power system operation. Voltage sag and other voltage disturbances will decrease the electrical torque of Squirrel-Cage Induction Generators (SCIG); consequently, the active power of Wind Energy Conversion System based SCIG (WECS- SCIG) will be reduced [4].Whereas, the mismatch between mechanical and electrical power make increasing the speed of rotor of SCIG. By increasing of rotor speed, the wind farm absorb more reactive power that can cause more depression in voltage magnitude. After clearing the fault, if the rotor speed does not over its critical speed, SCIG can get the equilibrium point. Otherwise, if the wind generators unable to withstand against faults, it must be disconnected from the grid and it may cause a cascading voltage collapse and the breakdown of the rest of wind farm generators [14]. In order to overcome above mentioned problems, normal operation wind turbine is necessary, for that new grid integration codes are passed, which will improve stability of WECS-SCIG under fault conditions occurring in the power system II. MODEL OF THE PROPOSED SYSTEM The power generated by wind turbine P W and speed ratio is given in below equations ) , ( v 2 1 3    p W C S P  (1) RESEARCH ARTICLE OPEN ACCESS