IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308 __________________________________________________________________________________________ Volume: 03 Issue: 04 | Apr-2014, Available @ http://www.ijret.org 587 UNIFIED POWER QUALITY CONDITIONER USING GENERALIZED FRYZE CONTROL STRATEGY Hardik Jayeshkumar Padariya 1 , Ch.V.Siva Kumar 2 , Chandni Yogeshkumar Joshi 3 1 ME Electrical, Electrical Department, Parul Institute of Engg, & Tech., Vadodara, Gujarat, India 2 Assistant Professor, Electrical Department, Parul Institute of Engg, & Tech., Vadodara, Gujarat, India 3 ME Electrical, Electrical Department, Parul Institute of Technology, Vadodara, Gujarat, India Abstract The active power filter controller is based on the instantaneous power theory. And it can be classified in two groups. The first one is based on the transformation from abc phase to three-orthogonal axes, and other is based on directly from abc. In first method abc phases are converted into αβ0 transformation and is called as p-q theory. In second method it deals with directly abc phase, so it is called as abc theory. In second theory current minimization method is used to apply in real time application. The second method is proposed as control strategy in this paper because it has some advantages over p-q theory. The shunt active power filter (APF) is used for current compensation and series active power filter is used for voltage compensation. The combination of both series and shunt active power is used to make Unified Power Quality Conditioner (UPQC). This has ability to eliminate voltage as well as current harmonics simultaneously. The matlab based simulation is done in this paper. Keywords: Active filters, Instantaneous active and reactive power, Instantaneous power theory, generalized fryze theory, UPQC. -----------------------------------------------------------------------***----------------------------------------------------------------------- 1. INTRODUCTION After many efforts, power quality conditioner was developed, which can solved the problem related to power quality. Nowadays more number of electronic devices is used by industries and residences in electrical system. For proper working of these devices, we have to provide high quality of power supply. But these devices inject harmonics in distribution system. This is one of the major problems in electrical system. The various power quality disturbances are transients, interruptions, voltage sag, voltage swell, voltage collapse, harmonics etc. It has been identified that power quality can be degraded both due to utility side abnormalities as well as the customer side abnormalities. The active filter which have ability to compensate nonlinear load current and unbalance supply voltage and they are used as shunt active filter and series active filter respectively. If we use both active filters integration then it is called as Unified Power Quality Conditioner (UPQC), which has ability to solved problem related to current and voltage harmonics simultaneously [5]. The most popular control theory, the instantaneous power theories are used. These are mainly two types. One of them is instantaneous p-q theory. And second is instantaneous abc theory. Almost all active filter developed are based on the instantaneous p-q theory. It works effectively for controlling the active filter and robust control system. On other side the instantaneous abc theory is also very effective for developing active filter and is called as generalized fryze theory, which is used the current minimization technique to implement in real time application. It has some advantage over the p-q theory. Because controller based on p-q theory is used the Clark transformation to calculate real and imaginary power by the use of those power it can possible to generate compensating quantities [1]. In this paper instantaneous abc theory is proposed for UPQC. Its fundamental is based on the p-q theory but not used Clark transformation. The minimization method based on Lagrange Multiplier method is used. And it is called as generalized fryze theory. 2. UNIFIED POWER QUALITY CONDITIONER Fig -1: Combine series and shunt compensation