IOSR Journal of Electrical and Electronics Engineering (IOSR-JEEE) e-ISSN: 2278-1676,p-ISSN: 2320-3331, Volume 12, Issue 2 Ver. I (Mar. – Apr. 2017), PP 01-10 www.iosrjournals.org DOI: 10.9790/1676-1202010110 www.iosrjournals.org 1 | Page Compensation of Harmonics of Fully Controlled Loads by Using SAHF Smt. SmitaSinghai 1 , Prof. Avinash Pandey 2 , Prof. Umesh Yadav 3 , Prof. Versha Singh 4 , Prof. S. Gupta 5 Department of Electrical Engineering, National Institute of Technology, Raipur (C.G.)(INDIA) Abstract: In this paper, Three Phase Shunt Active Harmonic Filter is used for harmonic compensation of fully Controlled loads by using new thyristorized Pulse Generator Circuits which generates 12 Pulses for two Non- Linear three phase Loads. The three phase Non-Linear Loads are connected at the secondary of three phase Transformers with Three Phase Breakers having Transition time 5/60seconds. A new Pulse Generator topology is used for generating pulses for each of three phase non-linear loads. The Circuit used for Compensation of Harmonics having three phase IGBT based Inverter. The IGBT base d Shunt Active Harmonic Filter gets firing Pulses from PLL phase Locked Loop& Hysteresis Switching HS. The used PLL extracts the Fundamental component of load current which is then multiplied with same RMS gain for generating the Reference current for Hysteresis Current Controller. The used Hysteresis Current Controller compares the reference current with measured current of Shunt Active Harmonic Filter for generating the pulse for three phase IGBT Inverter. Keywords: Shunt Active harmonic filter (SAHF), IGBT inverter, Phase locked loop (PLL), Hysteresis Switching (HS), Point of common coupling (PCC), Thyristorized pulse generator. I. Introduction All Computer & electronics loads, the use of electronic ballasts for fluorescent lighting and the extensive use of power semiconductor switches, such as in solid-state drives, all have greatly increased the nonlinear loads on power system. . However, with the large increase in the number of nonlinear loads in recent years, the distribution network response may not be so straightforward. That is, it is no longer possible to predict the network response with the same level as we obtain previously. For example, voltage reduction reduces power consumption; but at the same time, it may cause significant increases in feeder and transformer currents. All Non-linear load causes generation of Harmonics current. When Harmonic current flows to system impedance, it causes generation of Harmonic Voltages. These harmonic interferences causes overheating of motor , transformers, derating of electrical wires and electronics Devices, Abnormal operation of protective Devices like Breakers, Relay, fuses, control units, decreased motor performances Furthermore, some electronic loads with regulated output voltages, such as active power factor-corrected rectifiers, exhibit constant power demand against voltage variation. All these undesirable effects result in reducing system stability. Harmonic interferences can be minimized by installing harmonic filters. There are passive and active harmonic filters [1] - [3]. Passive harmonic filters have a pre-determined frequency bandwidth and are capable of minimizing fixed orders of harmonics only. Active harmonic filters are more sophisticated and can inject anti-phase harmonic currents to the systems for harmonic compensation. They are therefore suitable for dynamic harmonic conditions where harmonic contents are varying. One kind of Active Filter is Shunt Active filter which is used for harmonic current compensation & Reactive power Compensation [4]. It‟s another kind is Series Active Harmonic filter that is used for suppressing the voltage Harmonics, Voltage flicker & decreasing the voltage Regulation [6]. The combination of these two is known as unified Power Quality Conditioner UPQC that is used for suppressing all Power Quality Problems [5][7-11]. In our Paper, we suggests Thyristorized pulse generator based Phase Locked Loop Controlled three phase IGBT Inverter used for eliminating all Power Quality problems generated by fully Controlled Non-linear loads [12-14]. The gate signal for IGBT is generated by Hysteresis Switching HS. The Hysteresis Switching has good Property of Unconditioned Stability, high Speed response & good Accuracy [15][16]. The suggested SAHF is investigated for Compensating all power Quality issues for Thyristorized Pulse Generator based fully Controlled Non-Linear loads. II. Proposed Methodology Our methodology uses Thyristorized Pulse Generator Controlled; Phase Locked Loop & Hysteresis Switching based IGBT Inverter used for removing all Power Quality Issues generated by fully Controlled Non- Linear Loads. For eliminating all Power Quality Problems generated by Thyristorized Controlled Non-Linear loads, used PLL & HS controlled IGBT based Inverter is connected at the Point of Common Coupling PCC.