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Comparison of PI and ANN Control Techniques for Nine Switches UPQC to Improve Power Quality and Mitigation of Voltage Sag & Swell SHAIK.MABUSUBANI PG Student, Dept of EEE, Sri Mittapalli College of Engineering, Guntur Dt, A.P, India. Email Id: [email protected]. SURESH KORNEPATI Associate Professor, Head, Dept of EEE, Sri Mittapalli College of Engineering, Guntur Dt, A.P, India. Email Id: [email protected]. Abstract- This paper presents a comprehensive review on the UPQC to reinforce power quality. Typically this can be often speculated to gift a broad outline on the varied possible intelligent controls used with UPQC. The most purpose of a UPQC is to control on voltage flicker/unbalance, reactive power and harmonics. In different words, the UPQC has the potential of up power quality at the purpose of installation on power industrial power systems. The appliance of computing is growing quick within the space of power electronics and drives. From olden days to now days we are using twelve switches used in back to back configuration. But now we are using nine switches instead of 12 switches. In 9 switch UPQC converter given the most useful benefits compared to 12 switches power converter. The nine switches UPQC converter gets the best results by using of two methods. They are one is PI controller technique and other one is ANN controller technique. By contrast PI and ANN, ANN is better than PI for power quality enhancement and voltage sag and voltage swell mitigations. The factitious neural network (ANN) is taken into account as a replacement tool to style management electronic equipment for powerquality (PQ) devices. A whole simulation study is administrated to analysis the performance of the ANN controller and compares its performance with the quality PI controller results. The nineswitch convertor has already been proved to possess sure benefits, additionally to its part saving topological feature. Despite these benefits, the nine-switch convertor has thus far found restricted applications because of its several perceived performance tradeoffs like requiring associate degree outsized dc-link capacitance, restricted amplitude sharing, and unnatural part shift between its 2 sets of output terminals. Rather than acceptive these tradeoffs as limitations, a nine-switch power conditioner is projected here that nearly “converts” most of those topological short comings into fascinating performance benefits. Aiming more to cut back its switch losses, Harmonics, Voltage Sag & Swell associate degree acceptable discontinuous modulation theme is projected and studied here thoroughly to doubly make sure that top reduction of commutations is achieved. With associate degree suitably designed management theme with PI and ANN with physical phenomenon controller then incorporated, the nine-switch convertor is shown to favorably raise the general power quality in Simulation, thus justifying its role as an influence conditioner at a reduced value. Index Terms-ANN, Active power filters, PI controller, nine switch converter, Power quality, UPQC. I.INTRODUCTION The use of electronic controllers within the electrical power-supply system has become quite common. These electronic controllers behave as nonlinear load and cause serious distortion within the distribution system and introduce unwanted harmonics within the supply system, resulting in slashed potency of the facility system network and instrumentality connected within the network [1]. To satisfy the wants of harmonic regulation, passive and active power filters area unit being employed together with the standard converters [2]. Presently, active power filters (APFs) have become value-effective attributable to cost reductions in power semiconductor devices, their auxiliary components, and integrated digital management circuits. Additionally, the APF conjointly acts as a powerconditioning device that provides a cluster of multiple functions, like harmonic filtering, damping, isolation and termination, load equalization, reactivepower management for power-factor correction and voltage regulation, voltage-flicker reduction, and/or their mixtures. Resent analysis focuses on use of the universal power quality conditioner (UPQC) to catch up on power-quality issues [3], [4]. The performance of UPQC principally depends upon however accurately and quickly reference signals area unit derived. Once economical extraction of the distorted signal, an acceptable dc-link current regulator is used to derive the particular reference signals. numerous management approaches, like the PI, PID, fuzzylogic, sliding-mode, predictive, unified constant frequency (UCF) controllers, etc., area unit in use [5]–[7]. kind of like the PI standard controller, the PID controller needs precise linear mathematical models, that area unit tough to get, and fails to perform satisfactorily beneath parameter variation nonlinearity load disturbance, etc. fashionable management theoretic controllers area unit state feedback controllers, self-tuning controllers, and model reference adjustive controllers, etc. These controllers conjointly would like mathematical models and area unit so sensitive to parameter variations [8]. In recent years, a serious effort has been afoot to develop new and unconventional management techniques that may typically augment or replace standard management techniques. Variety of unconventional management techniques have evolved, providing solutions to several tough management issues in trade and producing sectors. not like their standard counterparts, these unconventional controllers (intelligent controllers) will learn, remember, and create choices. Artificial intelligence (AI) techniques, notably the NNs, area unit having a major impact on power-electronics applications. Neural-network-based managementlers give quick dynamic response whereas maintaining the soundness of the device system over a good in operation vary and area unit thought of as a brand new tool to style control circuits for PQ devices [9]– [12]. Over the previous couple of years, major analysis works are disbursed on feedback circuit style for UPQCs with the target of getting reliable management algorithms and quick response procedures to get the switch management signals [13]–[15]. During this paper, for raising the performance of a UPQC, a multilayer feed forwardtype ANN-based managementler is meant for the present control of the shunt active filter rather than the standard PI controller. Associate rule for coaching the ANN controller is developed and trained offline. Numerous simulation results area unit given and verified through an experiment, and compare the performance of the ANN controller with standard PI controller results. A DSP-based microcontroller is employed for the period of time simulation and implementation of the management rule. Since its initial introduction, static power convertor development has full-grown quickly with several convertor topologies currently pronto found within the open literature. Incidental this development is that the equally speedy identification of application areas, wherever power converters will contribute absolutely toward raising the general system quality [1], [2]. In most cases, the known applications would need the ability converters to be connected nonparallel [3] or shunt [4], looking on the operational situations into consideration. Additionally, they have to be programmed with voltage, current, and/or power regulation schemes in order that they\'ll swimmingly make amends for harmonics, reactive power flow, unbalance, and voltage variations. For even additional tight regulation of provide quality, each a shunt and a series convertor square measure more with one amongst them tasked to perform voltage regulation, whereas the opposite performs current regulation. nearly always, these 2 converters square measure connected in an exceedingly back to-back configuration [5], victimization twelve switches in total and sharing a typical dc-link capacitance, as mirrored by the configuration drawn in Fig. 1(a). Wherever obtainable, a small supply may be inserted to the common dc link, if the intention is to supply for distributed generation in an exceedingly small grid [6], while not considerably impacting on the long proved correct functioning of the succeeding configuration. Even though facing no major operative issues at the present, enhancements through topological modification or replacement of the consecutive configuration to scale back its losses, part count, and quality would still be favored, if there\'s no or solely slight expected trade-off in performance. A classical different that may straight off be brought out for thought is that the direct or indirect matrix device, wherever eighteen switches area unit employed in total. That represents six switches quite the consecutive configuration, however has the advantage of removing the intermediate electrical condenser for compactness and period of time extension. If the significant switch count remains of concern, those indirect thin matrix converters planned in [7], [8] is thought-about, wherever the minimum switch count getable is 9, however at the expense of supporting solely one-way power flow. Neither storage electrical condenser nor dc micro source is once more required, that therefore renders the traditional and thin matrix converters as not the wellliked selection, if ride-through could be a demand. Matrix converters also are not most popular, if voltage buck and boost operations area unit each required for a specified direction of power flow. frequency operation on the 2 interfaced ac systems that then makes it unsuitable for applications like utility steam-powered adjustable speed drives and series-shunt power conditioners. Yet another reduced semiconductor topology is found in [9], wherever the B4 device is introduced for dc– ac or ac dc energy conversion. The B4 device uses four switches to create 2 section legs with its third section drawn from the centre of a split dc electrical phenomenon link. For fastening 2 ac systems along, 2 B4 converters area unit required with their split dc link shared [10]. The full variety of switches required is therefore eight, that most likely is that the minimum possible for interfacing 2 ac systems. The ensuing ac–dc–ac device ought to then be a lot of truly cited because the B8 device. The B8 device is, however, known to suffer from massive dc-link voltage variation, unless each systems area unit of constant frequency and synchronized in order that no basic current flows through the dc link. That actually could be a constraint, additionally to the lower ac voltage that may be made by every B4 device from its given dc-link voltage. More significantly, a far larger dc-link capacitance and voltage ought to be maintained, so as to supply similar ac voltage amplitudes as for the consecutive convertor. Uncalled-for to mention, the larger dc-link voltage would amplify the semiconductor switches unnecessarily, and would possibly to some extent overshadow the saving of 3 semiconductor switches created potential by the nine-switch topology. The attractiveness of the nine-switch convertor, if so any, is thus not nonetheless absolutely brought out by those existing applications mentioned in [13]–[15]. Though follow-up topological extensions will later be found in [16], wherever a Z-source network and different modulation schemes are introduced, they didn’t absolutely address those crucial limitations sweet-faced by the nine-switch convertor, and not its ancient consecutive counterpart. Overcoming some limitations of the B8 device is that the 5 leg device introduced in [11], that conceptually is viewed as adding a fifth section leg to the B8 device. The other section leg is shared by the 2 interfaced ac systems with currently no massive basic voltage variation ascertained across its dc link. The sole constraint here is that the imposition of common Presenting a much better reduced semiconductor different for top quality series–shunt compensation, this paper proposes one stage integrated nine-switch power conditioner, whose circuit association is shown in Fig. 1(b). As its name roughly inferred, the planned conditioner uses a nine-switch convertor with 2 sets of output terminals, rather than the same old twelve switch back-to back convertor. The nineswitch convertor was earlier planned in [12] and [13] at regarding a similar time, and was counseled for twin motor drives [14], rectifier–inverter systems, and uninterruptible power provides [15]. Despite functioning as supposed, these applications are burdened by the restricted part shift and strict amplitude sharing enforced between the 2 terminal sets of the nine-switch convertor. Investigating more by taking a more in-depth read at those existing applications delineate earlier, a general note discovered is that they normally use the nineswitch convertor to exchange 2 shunt converters connected consecutive. Such replacement can limit the total functionalities of the nine-switch convertor, as explained in Section II. Within the same section, an alternate conception is mentioned, wherever the nine-switch convertor is chosen to exchange a shunt associate degreed a series convertor found in an integrated power conditioner, rather than 2 shunt converters. Underlying operational principles are mentioned comprehensively to demonstrate however such “series–shunt” replacement will induce the total blessings of the nine-switch convertor, whereas nonetheless avoiding those limitations sweet-faced by existing applications. Details explaining sleek transitions between traditional and sag operational modes are provided to clarify that the lot of restricted nine-switch convertor won\'t underperform the lot of freelance back-to back convertor even for sag mitigation. During voltage sags, the second set of management schemes conjointly has the flexibility to endlessly keep the load voltages inside tolerable vary. This sag mitigation ability, along with different abstract findings mentioned during this paper however not within the open literature, has already been verified in experiment with favorable results discovered. modification of electrical hundreds nature. These hundreds area unit at the same time the key causers and also the major victims of power quality issues [8]. because of their non-linearity, of these hundreds cause disturbances within the voltage undulation. along side technology advance, the organization of the worldwide economy has evolved towards globalisation and also the profit margins of the many activities tend to decrease [11]. The magnified sensitivity of the overwhelming majority of processes (industrial, services and even residential) to PQ issues turns the provision of electrical power with quality an important issue for fight in each activity sector. the foremost crucial area unitas are the continual method trade and also the info technology services [15]. once a disturbance happens, immense money losses could happen, with the ensuing loss of productivity and fight. though several efforts are taken by utilities, some shoppers need tier of PQ beyond the extent provided by fashionable electrical networks [12]. this means that some measures should be taken so as to attain higher levels of Power Quality. III.UNIFIED POWER QUALITY CONDITIONER Fig. 1. (a) back-to-back and (b) nine-switch power conditioners. II.POWER QUALITY Power Quality (PQ) connected problems area unit of most concern today. The widespread use of equipment, like info technology instrumentality, power physical science like adjustable speed drives (ASD), programmable logic controllers (PLC), energy-efficient lighting, diode to a whole The Unified Power Quality Conditioner may be a custom power device that\'s used within the distribution system to mitigate the disturbances that have an effect on the performance of sensitive and/or essential load [19]. it\'s a kind of hybrid APF and is that the solely versatile device which might mitigate many power quality issues connected with voltage and current at the same time thus is multi functioning devices that compensate numerous voltage disturbances of the ability offer, to correct voltage fluctuations and to stop harmonic load current from getting into the ability system. The system configuration of a single-phase UPQC is shown in Fig. 2. Unified Power Quality Conditioner (UPQC) consists of 2 IGBT primarily based Voltage supply converters (VSC), one shunt and one series cascaded by a typical DC bus. The shunt convertor is connected in parallel to the load. It provides power unit support to the load and provides harmonic currents. Whenever {the offer the availability the provision} voltage undergoes sag then series convertor injects appropriate voltage with supply [2]. Therefore UPQC improves the ability quality by preventing load current harmonics and by correcting the input power issue. the most elements of a UPQC square measure series and shunt power converters, DC capacitors, low-pass and high-pass passive filters, and series and shunt transformers the most purpose of a UPQC is to catch up on offer voltage power quality problems, such as, sags, swells, unbalance, flicker, harmonics, and for load current power quality issues, such as, harmonics, unbalance, reactive current, and neutral current. The key elements of this technique square measure as follows. 1) 2 inverters —one connected across the load that acts as a shunt APF and different connected nonparallel with the road as that of series APF. 2) Shunt coupling inductance Lsh is employed to interface the shunt electrical converter to the network. It conjointly helps in smoothing this wave. Generally associate isolation electrical device is employed to electrically isolate the electrical converter from the network. 3) a typical dc link that may be fashioned by employing a condenser or associate inductance. In Fig. 2, the dc link is accomplished employing a condenser that interconnects the 2 inverters and conjointly maintains a continuing independent dc bus voltage across it. 4) Associate LC filter that is a passive low-pass filter (LPF) and helps to eliminate high-frequency switch ripples on generated electrical converter output voltage. 5) Series injection electrical device that\'s accustomed connect the series electrical converter within the network. an acceptable flip magnitude relation is commonly thought-about to scale back the voltage and current rating of series electrical converter. In principle, UPQC is associate integration of shunt and series APFs with a typical independent dc bus. The shunt electrical converter in UPQC is managementled in current management mode such it delivers a current that is adequate to the set price of the reference current as ruled by the UPQC control algorithmic program [20]. To boot, the shunt electrical converter plays a vital role in achieving needed performance from a UPQC system by maintaining the dc bus voltage at a group reference price. so as to cancel the harmonics generated by a nonlinear load, the shunt electrical converter ought to inject a current. Similarly, the series electrical converter of UPQC is managementled in voltage control mode such it generates a voltage and injects nonparallel with line to realize a curved, free from distortion and at the required magnitude voltage at the load terminal. Within the case of a voltage sag condition, actual supply voltage can represent the distinction between the reference load voltage and reduced offer voltage, i.e., the injected voltage by the series electrical converter to take care of voltage at the load terminal at reference price. Altogether the reference papers on UPQC, the shunt electrical converter is operated as controlled current supply and also the series electrical converter as controlled voltage supply except during which the operation of series and shunt inverters is interchanged. A unified power quality conditioner (UPQC) may be a device .The UPQC, sort of a UPFC, employs 2 voltage supply inverters (VSIs) that area unit connected to a standard dc energy storage condenser. One among these 2 VSIs is connected serial with the AC line whereas the opposite is connected in shunt with an equivalent line. A UPFC is used in an exceedingly power gear mechanism to perform shunt and series compensation at an equivalent time. Equally a UPQC may perform each the tasks in an exceedingly power distribution system. However, at now similarities within the operational principles of those 2 devices finish. Since an influence cable typically operates in an exceedingly balanced, distortion (harmonic) free surroundings, a UPFC should solely give balanced shunt or series compensation. An influence distribution system, on the other hand, could contain unbalance, distortion and even dc elements. Thus a UPQC should operate below these surroundings whereas providing shunt or series compensation. The UPQC may be a comparatively new device and not a lot of work has been reported thereon however. It has been viewed as an integration of series and shunt active filters. It has been shown that it may be accustomed attenuate current harmonics by inserting a series voltage proportional to the road current. Instead, the inserted series voltage is supplemental to the voltage at the purpose of common coupling specified the device will give a buffer to eliminate any voltage dip or flicker. It is additionally potential to control it as a mixture of those 2 modes. In either case, the shunt device is employed for providing a path for the important power to flow to assist the operation of the series connected VSI. Additionally enclosed during this structure may be a shunt passive filter to that all the comparatively low frequency harmonics area unit directed. Fig. 2: UPQC general block diagram IV.OVERALL CONTROL CIRCUIT CONFIGURATION OF NINE SWITCH UPQC be then adore pure curving signal with unity (p.u.) amplitude. The extraction of unit vector templates is U a sin( wt ) U b sin( wt 120) (1) U c sin( wt 120) Multiplying the height amplitude of basic input voltage with unit vector templates of equation (1) offers the reference load voltage signals, V *abc Vm .U abc (2 ) The error generated is then taken to a physical phenomenon controller to get the desired gate signals for series APF. The unit vector template are often applied for shunt Fig.3 Extraction of Unit Vector Templates and three-Φ Reference Voltages shown within the Fig.3.The unit vector templates square measure generated APF to compensate the harmonic current generated by non-linear load. The shunt APF is employed to catch up on current harmonics likewise on maintains the dc link voltage at constant level [13-14]. to realize the higher than mentioned task. REFERENCE GENERATION (PHASE LOCKED LOOP) Reference currents and voltages square measure generated victimization part secured Loop (PLL). The management strategy is predicated on the extraction of Unit Vector Templates from the distorted input provide. These templates are going to be then adore pure curving signal with unity (p.u.) amplitude. The 3-ph distorted input supply voltage at PCC contains basic element and distorted element. to induce unit input voltage vectors Uabc, the input voltage is perceived and increased by gain adequate to 1/Vm, wherever Vm is adequate to peak amplitude of basic input voltage. These unit input voltage vectors square measure taken to part secured loop (PLL). With correct part delay, the unit vector templates square measure generated. The management strategy is predicated on the extraction of Unit Vector Templates from the distorted input provide. These templates are going to Fig.3. Extraction of 3-Φ Reference Voltages Unit Vector Templates The dc link voltage is perceived and compared with the reference dc link voltage. A PI controller then processes the error. The signal from PI controller is increased with unit vector templates of equation (1) giving reference supply current signals. The supply current should be adequate to this reference signal. so as to follow this reference current signal, the 3-phase supply currents square measure perceived and compared with reference current signals. The error generated is then processed by a physical phenomenon current controller with appropriate band, generating gating signals for shunt APF. The 9 Switch UPQC uses 2 consecutive connected 3 part VSI‟s sharing a standard dc bus. The physical phenomenon controller is employed here to manage the switch of the each VSI’s. In order to own distortion less load voltage, the load voltage should be adequate to these reference signals. The measured load voltages square measure compared with reference load voltage signals. The error generated is then taken to a physical phenomenon controller to get the desired gate signals for series APF. The unit vector templates are often applied for shunt APF to compensate the harmonic current generated by non-linear load. The shunt APF is employed to catch up on current harmonics likewise on maintains the dc link voltage at constant level. to realize the higher than mentioned task the dc link voltage is perceived and compared with the reference dc link voltage. A PI controller then processes the error. The signal from PI controller is increased with unit vector templates of equation (1) giving reference supply current signals. The supply current should be adequate to this reference signal. so as to follow this reference current signal, the 3-ph supply currents square measure perceived and compared with reference current signals. The error generated is then processed by a physical phenomenon current controller with appropriate band, generating gating signals for shunt APF. V. CONTROL STRATEGY OF NINE SWITCH UPQC Static Shunt Compensator using PI Nine Switch UPQC consists of series compensator and shunt compensator. The shunt compensator is managementled by a PWM current control formula, whereas the series convertor is managementled by a PWM voltage control formula. in step with the adopted management theme, these 2 components of 9 Switch UPQC have totally different functions as follows: Static Shunt Compensator Shunt electrical converter control: during this study, shunt electrical converter undertakes 2 main duties. initial is compensating each current harmonics generated by nonlinear load and reactive power, second is injecting active power generated by PV system. The shunt electrical converter dominant system ought to be designed during a manner that it\'d give the power of enterprise 2 higher than duties. Shunt electrical converter management calculates the compensation current for current harmonics and reactive power once PV is out of the grid. the facility loss caused by electrical converter operation ought to be thought-about during this calculation. Also, shunt electrical converter management undertakes the duty of (stabilizing) DC link voltage throughout series electrical converter operation to compensate voltage distortions. DC link electrical condenser voltage dominant loop is employed here by applying PI controller. Fig.4 shows the circuit diagram of shunt electrical converter dominant. Fig .4.Control block diagram of shunt inverter using PI. Shunt electrical converter management in interconnected mode: Mode one of shows UPQC shunt voltage supply electrical converter dominant diagram applying synchronous coordinate system theory technique wherever sensitive load currents area unit Ia, Ib and Ic Measured load currents applying synchronous coordinate system conversion technique (dq0), area unit transferred to dq0 frame victimization curved functions. Sinusoidal functions are obtained by PLL using grid voltage. Currents during this synchronous reference area unit rotten to 2 DC and AC (50 Hz) quantities (using ~ sign higher than the parameter). dq 0 Ildq 0 Tabc I abc dq 0 Tabc cos 2 sin 3 1 2 ( 1) 2 2 cos cos 3 3 2 2 sin sin 3 3 1 1 2 2 Ild Ild Ild , Ilq Ilq Ilq (2) (3) where, Id is active and IQ is reactive a part of power. AC and DC components is extracted by an occasional pass filter.In this case: Il I s I c (4) In Eq. 4, Is is that the supply current, Il is that the load current and Ic is that the compensating currentinjected by shunt electrical converter. If compensation reference currents area unit thoughtabout as follow: I *fd Ild , I *fq Ilq (5) In this case, the system`s currents are: I sd Ild , I sq I lq (6) In the Eq. 6, simply the load current harmonics area unit remunerated. If power issue is taken into account too, the reference currents would be as follow: I *fd Ild , I *fq Ilq (7) then system currents are: I sd Ilq , I sq 0 average worth of DC bus. alternative distortions like unbalanced and unexpected load current variations will cause oscillation in DC bus voltage. so as to trace the error exists between the measured and desired worth of electrical condenser voltage, a PI controller is applied. This dominant signal is applied to current system in shunt voltage supply during a manner that it management DC electrical condenser voltage by getting needed active power (Id) from the grid. The output a part of PI controller (Δidc), is additional to the letter of the alphabet a part of reference current, where, the reference current would modification as follow: I cd* Ild idc , I cq* Ilq (9) As it is shown in Fig. 4, the reference currents can transfer to fundamentals frame by reverse changing the synchronous coordinate system, as Eq. 1. Resulted reference currents are compared with shunt electrical converter output currents (Ifa, Ifb, Ifc) during a PWM current controller (hysteresist type) and needed dominant pulses area unit generated. Applying these signals to shunt electrical converter power switches gate, needed compensation current is generated by electrical converter. In addition to earlier duties, shunt electrical converter management ought to inject active power of PV system to the grid once PV is working. Active power is injected to grid by electrical condenser voltage dominant loop. In alternative words, once voltage will increase and reaches to {the worth|the worth} that is quite the reference voltage value, shunt electrical converter injects active power to grid and once it decreases to worth that is a smaller amount than the reference voltage value; shunt electrical converter receives active power from the grid. Static Shunt Compensator using ANN (8) So, no harmonic and reactive power are provided by the supply. Switching losses and therefore the power that the series electrical converter receives from electrical condenser, will scale back the voltage In Figure.5 the fast current of the nonlinear load is expanded into three terms. the primary term is that the load functions sent from PLL (Phase latched Loop) in accordance with equation.(3) I Ldq 0 Tabc dq 0iLabc (10) By this remodel, the basic positive sequence parts area unit remodeled into dc Quantities in d and letter of the alphabet axes, which may simply be extracted by low-pass, filter (LPF). Fig.6. Control block diagram of series inverter using PI. Fig.5. Control of the shunt Converter of the Nine Switch UPQC using ANN. All harmonic parts area unit remodeled into ac quantities with a harmonic shift I Lq i Lq i Lq Since iL is ic (11) (12) This means there\'s no harmonics and reactive parts within the system currents. The change loss will cause the dc link electrical condenser voltage to decrease. alternative disturbances, like unbalances and unexpected variations of masses can even cause this voltage to fluctuate. so as to avoid this, in Figure four. a PI controller is employed. The input of the PI controller is that the error between the particular electrical condenser voltage and therefore the desired worth, its output then additional to the reference current part within the d-axis to create a replacement. Series inverter control using PI: The duty of series electrical converter is compensating voltage distortions that ar caused by fault in distribution grid. Series electrical converter management calculates the voltage reference values, that ar injected to grid by series electrical converter. In order to regulate series electrical converter of UPQC, load curving voltage dominant strategy is projected. during this condition, UPQC series electrical converter would be controlled during a approach that it compensates the total distortions and helps the voltage of load voltage keep (balanced curving 3-phase). so as to succeed in this aim, synchronous frame of reference theory is applied (11). In this methodology the specified worth of load section voltage is replaced in d and q-axises rather than high pass and low pass filters. Load voltage ought to be utterly a curving perform and has constant frequency and amplitude. Desired voltage of load is as combining weight. 14: * ldq 0 V * labc V T dq 0 abc * labc .V Vm 0 0 Vm cos t Vm cos t 120 Vm cos t 120 (13) (14) where, Vm is desired peak worth of load voltage and (θ) is voltage point that is calculated by section latched loop (PLL). By subtracting the specified worth of d-axis section voltage from Vsd, all distortions in d-axis ar obtained. Also, the specified worth of load section voltage in q-axis is zero. In alternative words, Vsq represents total q-axis distortions. So, series compensation reference voltage is resulted by combining weight. 16: * * V fdq 0 Vldq 0 Vsdq 0 (15) These voltages ar compared with associate angular wave form in PWM controller and needed dominant pulses (g1,..., g6) ar generated to be applied to series voltage supply electrical converter switches. This corrected methodology is programmable with an occasional price. the opposite advantage is that the dominant system`s calculation time is shortened and then dominant system`s response is quicker. Fig.6 shows the diagram of series compensator`s dominant circuit applying synchronous frame of reference methodology. so as to enhance series electrical converter operation, SPWM methodology is employed wherever, the resulted worth of subtracting from Vfabc is increased to a continuing constant and also the obtained worth is superimposed to . Applying this methodology distinctively improves operation of series electrical converter. VI.ARTIFICIAL NEURAL NETWORK The ANN controller used is a feed forward one, comprising three neuron layers, the input layer, the hidden layer and the output layer shown in the Fig 8. The input layer offers connection points to transmit the input signal to the hidden layer. The latter begins the learning process and the output layer continues the learning process and provides outputs. The hidden layer neurons have a tan-seg-moid transfer function, and the output layer neurons have a linear transfer function. The control objective of the NN is to provide the wanted proper gating patterns of the PWM inverter, leading to adequate tracking of the APF reference phase currents and constant DC voltage. Neurons in the hidden layer is specified as the minimum number that produces the permitted training criterion. The training criterion is taken as the mean square error of the NN outputs with a value of 0.0001. Sufficient input-output training examples are obtained by using the triangular carrier modulation technique. Series inverter control using ANN: The system aspect voltage might contain negativezero-sequence still as harmonics parts which require to be eliminated by the series compensator [15-16]. The management of the series compensator is shown in Figure.7. The system voltages ar detected then reworked into synchronous dq-0 frame of reference exploitation equation (6). Fig.7 Control block diagram of the series converter of the UPQC using ANN. Fig.8 The basic architecture of the feed forward neural network with accompanying equations that describe the transfer functions between layers. An ANN is basically a cluster of fittingly interconnected non-linear components of terribly easy kind that possess the flexibility of learning and adaptation. These networks square measure characterized by their topology, the means during which they convey with their atmosphere, the style during which they\'re trained and their ability to method data [18]. Their easy use, inherent reliableness and fault tolerance has created ANNs a viable medium for management. An alternate to fuzzy controllers in several cases, neural managementlers share the requirement to switch laborious controllers with intelligent controllers so as to extend control quality. A feed forward neural network works as compensation signal generator. This network is meant with 3 layers. The input layer with 7 neurons, the hidden layer with 21 and therefore the output layer with 3 neurons. Activation functions chosen square measure tan sigmoid and pure linear within the hidden and output layers severally. The speedy detection of the disturbance signal with high accuracy, quick process of the reference signal, and high dynamic response of the controller square measure the prime needs for desired compensation just in case of UPQC. the traditional controller fails to perform satisfactorily below parameter variations nonlinearity load disturbance, etc. now shows that NN-based controllers offer quick dynamic response whereas maintaining stability of the device system over wide operational vary. Shows The Fig.9 ANN is created of interconnecting artificial neurons. It is basically a cluster of befittingly interconnected nonlinear components of terribly straightforward kind that possess the power to find out and adapt. It resembles the brain in 2 aspects: 1) the data is nonheritable by the network through the educational method and 2) interneuron association strengths square measure wont to store the data. These networks square measure characterized by their topology, the means during which they convey with their atmosphere, the style during which they are trained, and their ability to method info. ANN has gained plenty of interest over the previous few years as a robust technique to solve several world issues. Compared to standard programming, they own the aptitude of finding issues that don't have recursive answer and square measure thus found appropriate to tackle issues that folks square measure sensible to unravel like pattern recognition. ANNs square measure getting used to solve AI issues while not essentially making a model of a true dynamic system. For up the performance of a UPQC, a multilayer feed forward- kind ANN-based controller is intended. This network is intended with 3 layers, the input layer with two, the hidden layer with twenty one, and also the output layer with one somatic cell, severally. Fig.9 The basic architecture of ANN This network is meant with 3 layers, the input layer with a pair of, the hidden layer with twenty one, and therefore the output layer with one vegetative cell, severally. The big information of the dc-link current for n and (n-1) intervals from the traditional methodology area unit collected and area unit hold on within the Mat lab space. These information area unit used for coaching the NN. The activation functions chosen area unit tan colon for hidden and input layers and pure linear within the output layer, severally. This multilayer feedforward-type NN works as a compensation signal generator. The topology of the ANN is as shown in Fig. 10. Fig.10 Block diagram of the ANN-based compensator for offline training. The compensator output depends on the evolution and its input. The NN is trained for output basic reference currents. The signals so obtained area unit compared during a physical phenomenon band current controller to produce change signals. VII. SIMULATION CIRCUITS Fig. 11 Block diagram of without UPQC Fig .12 Block diagram of Nine Switch UPQC Fig.13 Block diagram of Nine Switch UPQC with PI controller Fig.14 Block diagram of Nine Switch UPQC with ANN controller Fig.15 Neural network sub circuit Fig.16 Neural network layer 1 Fig.18. without UPQC at Load Voltage, input Voltage, and Injected Voltage Fig.17 Neural network layer 2 VIII.SIMULATION RESULTS The harmonic content of input and output of the Bridge convertor ar shown in Fig.18. (three phase voltages) and Figure nine. (three phase currents). because of non-linear masses, like massive thyristor power converters, rectifiers, voltage and current unsteady because of arc in arc furnaces, sag and swell because of the shift of the loads etc. one in every of the numerous solutions is that the use of a combined system of shunt and active series filters like 9 Switch Unified power quality conditioner (UPQC) . Fig.19.PI without UPQC at Load Current, input Current, and Injected Current This device combines a shunt active filter beside a series active filter in an exceedingly consecutive configuration, to at the same time compensate the provision voltage and also the load current or to mitigate any kind of voltage and current fluctuations and power issue correction in an exceedingly power distribution network. The management methods used here are supported PI & ANN controller of the 9 Switch UPQC well. The management methods are sculptured victimization MATLAB/SIMULINK. The simulation results are listed compared of various management methods are shown in figures. To verify the operational performance of the projected 9 Switch UPQC, a 3-Φ electrical system, a PLL extraction circuit with physical phenomenon controlled 9 Switch UPQC is simulated victimization MATLAB software system. Figure 22. Shows the unit vector templates generated by victimization projected management technique. Fig.20.PI controller with SAG condition at Load Voltage, input Voltage, and Injected Voltage Fig.21.PI controller with SAG condition at Load Current, input Current, and Injected Current Fig.24.PI controller with SWELL condition at Load Current, input Current, and Injected Current Fig.22.Dc voltage, without compensation and Neutral compensation current Fig.25.PI controller with SAG & SWELL condition at Load Voltage, input Voltage, and Injected Voltage Fig.23.PI controller with SWELL condition at Load Voltage, input Voltage, and Injected Voltage Fig.26.PI controller with SAG & SWELL condition at Load Current, input Current, and Injected Current Fig.27.ANN controller with SAG condition at Load Voltage, input Voltage, and Injected Voltage Fig.30.ANN controller with SWELL condition at Load Current, input Current, and Injected Current Fig.28.ANN controller with SAG condition at Load Current, input Current, and Injected Current Fig.31.ANN controller with SAG & SWELL condition at Load Voltage, input Voltage, and Injected Voltage Fig.29.ANN controller with SWELL condition at Load Voltage, input Voltage, and Injected Voltage Fig.32.ANN controller with SAG & SWELL condition at Load Current, input Current, and Injected Current Without UPQC Utility side voltage THD is 4.15% at 3rd harmonic order Fig.33. without UPQC Utility side voltage at 3rd harmonic Without UPQC utility side Current THD is 12.11% at 3rd harmonic order Fig.34. without UPQC utility side current at 3 harmonic rd Without UPQC utility side voltage THD is 4.15% at 5th harmonic order Fig.35. without UPQC Utility side voltage at 5th harmonic Without UPQC Utility side Current THD is 12.15% at 5th harmonic order Fig.36. without UPQC Utility side current at 5th harmonic Without UPQC Utility side voltage THD is 4.15% at 7th & 9th harmonic orders Fig.37. without UPQC Utility side voltage at 7th & 9th harmonics Without UPQC Utility side Current THD is 12.17% at 7th & 9th harmonic orders Fig.38. without UPQC Utility side current at 7th & 9th harmonics Utility side voltage THD with pi 3.99% at 3rd harmonic order Utility side current THD with pi 2.33% at 5th harmonic order Fig.39. Utility side voltage THD with PI at 3rd harmonic Fig.42. Utility side current THD with PI at 5th harmonic Utility side current THD with PI 2.29% at 3rd harmonic order Utility side voltage THD with PI 3.88% at 7th & 9th harmonic orders Fig.40. Utility side current THD with PI at 3rd harmonic Fig.43. Utility side voltage THD with PI at 7th & 9th harmonics Utility side voltage THD with PI 4.09% at 5th harmonic order Utility side current THD with PI 2.26% at 7th & 9th harmonic orders Fig.41. Utility side voltage THD with PI at 5th harmonic Fig.44. Utility side current THD with PI at 7th & 9th harmonics Utility side voltage THD with ANN 1.36% at 3rd harmonic order Utility side current THD with ANN 1.31% at 5th harmonic order Fig.45. Utility side voltage THD with ANN at 3rd harmonic Fig.48. Utility side current THD with ANN at 5th harmonic Utility side current THD with ANN 1.48% at 3rd harmonic order Utility side voltage THD with ANN 1.37% at 7th & 9th harmonic orders Fig.46. Utility side current THD with ANN at 3rd harmonic Fig.49. Utility side voltage THD with ANN at 7th & 9th harmonics Utility side voltage THD with ANN 1.35% at 5th harmonic order Utility side current THD with ANN 1.39% at 7th & 9th harmonic orders Fig.47. Utility side voltage THD with ANN at 5th harmonic Fig.50. Utility side current THD with ANN at 7th & 9th harmonics IX. RESULT TABLE Order of harmonics WITHOUT UPQC utility side voltage WITHOUT UPQC utility side current UPQC with PI controller utility side voltage UPQC with PI controller utility side current UPQC with ANN controller utility side voltage UPQC with ANN controller Utility side current 3rd 4.15 12.11 3.99 2.29 1.36 1.48 5th 4.15 12.15 4.09 2.33 1.35 1.31 7th &9th 4.15 12.17 3.88 2.26 1.37 1.39 X. CONCLUSION The UPQC performance mainly depends upon how accurately and quickly reference signals are derived. Then conventional compensator was replaced with PI controller and ANN. 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Trans. Distr., March, Vol. 147, No. 2 [30] H.Toodeji, S.H.Fathi, “Power Management and Performance Improvement in Integrated System of Variable Speed Wind Turbine and UPQC” Amirkabir University of Technology, Tehran, IEEE 2009. Mr. SHAIK. MABUSUBANI is a student of Sri Mittapalli College of Engineering, Guntur, AP. Currently he is pursuing M.Tech in Power Electronics and Electrical Drives (12U91D5408) from S.M.C.E. He completed B.Tech (E.E.E.) in Chalapati Institute of Technology. His area of interests include Power Quality by Custom Power Devices, controllers like controllers, Artificial intelligence controlling techniques, power Electronics & Drives, Neuro controller Neuro-fuzzy controllers, renewable energy resources, Fuzzy controllers. Mr. SURESH. KORNEPATI presently working as Associate Professor & Head, Deportment of EEE in Sri Mittapalli College of Engineering, Guntur, A.P. His area of interests include renewable energy resources, Power Quality by custom Power Devices, Power System Operation, Control & Stability, Intelligent controlling techniques and Power Electronics & Drives.