Department of Electrical and Electronics Engineering

Permanent URI for this collectionhttp://localhost:4000/handle/123456789/1925

Browse

Has files: NoSubject: search.filters.subject.UPQC-DG

Search Results

Now showing 1 - 5 of 5
  • No Thumbnail Available
    Item
    A Simple Approach to Improvement in Performance of UPQCDG in presence of Unbalanced Load
    (IEEE, 2017) Bhanot, Surekha; Mathur, Hitesh Datt; Patel, Ashish
    In this paper, an improved Power Angle Control (PAC) method for UPQC-DG has been proposed for effective compensation of unbalanced loads. UPQC-DG provides a simultaneous solution to power quality and renewable integration. PAC methods have been developed for UPQC-DG to enhance VA utilization of series and shunt APFs of UPQC-DG. In case of unbalanced loads, existing PAC methods result in circulation of reactive power and increased VA loading of UPQC-DG. PAC method proposed in this work, is designed to tackle above-mentioned issues. Also, proposed PAC method is based on Synchronous Reference Frame (SRF) theory, which makes it robust to non-ideal voltages. Performance of proposed PAC method has been tested using real time simulation performed in Opal-RT. Simulation results show superior performance of UPQC-DG in presence of unbalanced and non-linear loads using proposed PAC method.
  • No Thumbnail Available
    Item
    Enhancing VA sharing between the shunt and series APFs of UPQC with a modified SRF-PAC method
    (Wiley, 2020-02) Mathur, Hitesh Datt; Bhanot, Surekha; Patel, Ashish
    This study proposes a synchronous reference frame (SRF) theory-based modified power angle control (PAC) method for unified power quality conditioner (UPQC). In the steady state of conventional UPQC, shunt active power filter (APF) supplies total reactive power demand, and series APF sits idle, leading to unbalanced VA loading of the two APFs and increase in overall VA rating of UPQC. PAC methods of UPQC have been devised for reducing the unbalance in VA loading of series and shunt APFs of UPQC by sharing reactive load power between the two APFs. SRF-based PAC methods are robust, but existing ones support only small values of power angle, and thereby limit the improvement in unbalance of VA loading of series and shunt APFs. In this work, a modified SRF-PAC method is proposed to support larger values of power angle, to load the two APFs in proportion to their VA ratings and thus yield smaller unbalance in VA loading of the two APFs of UPQC. Also, a modified power angle estimation is proposed to ensure that voltage and VA load on series converter does not go beyond the rated values. Controller hardware in loop simulations and hardware experiments validate the proposed control method.
  • No Thumbnail Available
    Item
    Optimum sizing of PV based UPQC-DG with improved power angle control
    (Elsevier, 2020-05) Bhanot, Surekha; Mathur, Hitesh Datt; Patel, Ashish; Yadav, Sisir K.
    Unified power quality conditioner with distributed generation (UPQC-DG) is a solution to the problems of power quality and integration of distributed renewable sources. UPQC, being a combination of series and shunt converters, can compensate for most power quality issues, but the use of two power converters increases the cost, and hence optimal sizing methods have been proposed in the literature. Sizing of UPQC-DG components, however, requires special consideration of power injected by DG. This paper proposes an optimum sizing method for UPQC-DG based on an improved power angle control (PAC) technique, which shares reactive power burden between series and shunt converters. Apart from optimal-sizing, this paper incorporates Volt-Ampere (VA) limits in the PAC method to ensure the operation of converters within designed ratings under all conditions. The performance of the proposed power angle control method has been tested for a case study system using Controller Hardware in Loop (CHIL), implemented with Opal-RT and Dspace/micro-labbox, and has been found superior to existing methods.
  • No Thumbnail Available
    Item
    An improved control method for unified power quality conditioner with unbalanced load
    (Elsevier, 2018-09) Mathur, Hitesh Datt; Bhanot, Surekha; Patel, Ashish
    This paper proposes an improved control method for Unified Power Quality Conditioner (UPQC) with unbalanced load. In UPQC, shunt APF is overburdened when it alone supplies total load reactive power. PAC method aims at effective utilization of series and shunt APFs by sharing reactive power burden between the two. In presence of unbalanced load, existing PAC methods can lead to circulation of reactive power between two APFs and thereby result in overloading of UPQC. Also, due to unbalanced compensating currents, DC link voltage contains second order oscillations, which deteriorates source current quality. In this work, a new PAC method is proposed, which avoids circulation of reactive power and unnecessary VA burden on UPQC. To suppress DC link voltage oscillations, proposed control employs a ‘mean block’ (moving average) at output of PI controller, which ensures balanced and harmonic free source currents. Also, a ‘percentage unbalance’ parameter has been proposed to quantify the unbalance in three phase quantities. Performance of proposed UPQC system is tested in the presence of non-linear, reactive and unbalanced loads. Dynamic performance of system is studied during grid disturbances such as voltage sag, swell, and change in load. Real time simulation carried out in Opal-RT validate the effectiveness of proposed method. The electrical circuit of UPQC is simulated with sub-microsecond time step on FPGA based computational engine of Opal-RT for better verification of the proposed contro
  • No Thumbnail Available
    Item
    A new SRF-based power angle control method for UPQC-DG to integrate solar PV into grid
    (Wiley, 2018-08) Mathur, Hitesh Datt; Bhanot, Surekha
    In this paper, a new synchronous reference frame theory–based power anglecontrol (PAC) method for unified power quality conditioner with distributedgeneration (UPQCDG) is proposed for effective grid integration of solar PV. InUPQCDG, shunt active power filter (APF) feeds power from distributed genera-tor to load, apart from supplying reactive power demand, which leads to increasein VA burden, hence its rating. Power angle control method aims at effective uti-lization of series and shunt APFs through sharing of reactive power to reduceVA burden on shunt APF. Proposed PAC method is based on instantaneousthree-phase power estimation technique, which is simple and robust and utilizesalready available measurements of UPQCDG. Performance of proposed systemis tested in the presence of nonlinear and reactive loads with solar PV genera-tion system. Dynamic performance of system is studied during grid disturbancessuch as voltage sag and swell, solar irradiation variation, and change in load.Effectiveness of proposed method is validated using real-time simulation per-formed in Opal-RT, in which electrical circuit of UPQCDGis simulated on FPGAcomputation engine with submicrosecond time step to emulate real hardwareclosely.