UPQC Implements The 3-Phase Shunt And Series Active Power Filter To Compensate Current And Voltage Harmonics

This paper presents the three phase shunt and series active power filter in order to reduce the current and voltage harmonics. To implement Unified Power Quality Conditioner (UPQC) control algorithm two control strategies p-q instantaneous power and d-q synchronous frame theory are used to mitigate the problems of power quality caused due to nonlinear loads. Both control theories performances are carried out and compared under nonlinear loads. The performance of UPQC with two control strategies has been tested in the Matlab/Simulink environment. The simulation results showed better performance for harmonic problem

Harmonic Power Compensation Capacity of Shunt APF and its Relationship to Design Parameters

VSI-based three-phase; power exchange mechanism; switching dynamics; three-phase systems; active losses; single-phase systems; power tetrahedron phasor diagram; shunt active power filter; harmonic power compensation capacity; four-wire systems; hysteresis band current contro

A New Controlling Technique for Elimination Lower Order Harmonics In A Three Phase PV Inverter System

In this paper, a new controlling technique for elimination lower order harmonics in a three phase PV inverter system topology consisting of a boost section, a low-voltage three-phase inverter with an inductive filter, and a step-up transformer has been proposed. This topology will reduce any lower order harmonics due to high-frequency pulse width modulation operation. However, the non-ideal factors in the system contribute to a important amount of lower order harmonics in the grid current. A new propose of inverter current control mitigates lower order harmonics is presented three phase PV inverter system. A new controller has designed and presented for the lower order harmonic compensation. In addition to that a proportional-resonant-integral (PRI) regulator has been designed. This paper includes an analysis to intend the value of the gain in the proportional controller to achieve an adequate level of harmonic compensation. This PRI controller eliminates the dc element in the control system and introduces even harmonics in the grid current in this topology. The dynamics of the system due to the communication between the PRI controller and the adaptive compensation scheme is also analyzed. The proposed system has constructed in MATLAB/SIMULINK software and the results have been shown

Sensorless Control of Induction Motors by the MSA based MUSIC Technique

This paper proposes a speed sensorless technique for induction motor drives based on the retrieval and tracking of the rotor slot harmonics (RSH). The RSH related to the rotor speed is first extracted from the stator phase current signature by the adoption of two cascaded ADALINEs (ADAptive Linear Element), whose output is the estimated slot harmonic. Then, the frequency of this slot harmonic as well as the speed is estimated by using minor space analysis (MSA) EXIN neural networks, which work on-line to iteratively compute the frequency of the slot harmonics based on MUSIC spectrum estimation theory. Thanks to its sample-based learning and the reduced mean square frequency estimation error, the speed estimation is fast and accurate. The proposed sensorless technique has been experimentally tested on a suitably developed test set-up with a 2-kW induction motor drive. It has been verified that this algorithm can track the rotor speed rapidly and accurately in a very wide speed range, working from rated speed down to 1.3 % of it

Regulatori struje aktivnih filtara snage za poboljšanje kvalitete snage: Tehnička analiza

Non-linear load deteriorates the quality of current waveforms at the point of common coupling of various consumers. Active power filter (APFs) is used to mitigate the most concern harmonic pollution in an electrical network. The controller part is the nucleus of an active power filter configuration. Active power filter performance is affected significantly by the selection of current control techniques. The active filter and its current control must have the capability to track sudden slope variations in the current reference to compensate the distorted current drawn by the voltage source inverter. Therefore, the choice and implementation of the current regulator is more important for the achievement of a satisfactory performance level. In this survey, technical reviews of various types of controllers covering a wide range have been presented. This work also reveals the advantages and disadvantages of the practiced control strategies. The effectiveness of the study will help the researchers to choose the proper control methods for various applicationsof active power filter.Nelinearni tereti pogoršavaju kvalitetu strujnih valova u točki u kojoj se spaja više potrošača. Aktivni filtar snage se koristi za ublažavanje najvažnijeg harmoničkog onečišćenja strujne mreže. Jezgra aktivnog filtra snage je regulator. Na performanse aktivnog filtra snage značajno utječe odabir upravljačke tehnike. Aktivni filtar i njegova tehnika upravljanja strujom moraju imati mogućnost pratiti nagle skokove u referentnoj vrijednosti struje kako bi mogli kompenzirati izobličenja struje koju vuče inverter naponskog izvora. Zato su izbor i implementacija regulatora struje iznimno važni za postizanje zadovoljavajuće razine performansi. U ovom pregledu su predstavljene tehničke recenzije koje pokrivaju širok raspon regulatora. Ovaj rad također otkriva prednosti i mane korištenih strategija upravljanja. Efektivnost ovog pregleda pomoći će istraživačima da izaberu ispravnu metodu upravljanja za različite aplikacije aktivnog filtra snage

Regulatori struje aktivnih filtara snage za poboljšanje kvalitete snage: Tehnička analiza

Non-linear load deteriorates the quality of current waveforms at the point of common coupling of various consumers. Active power filter (APFs) is used to mitigate the most concern harmonic pollution in an electrical network. The controller part is the nucleus of an active power filter configuration. Active power filter performance is affected significantly by the selection of current control techniques. The active filter and its current control must have the capability to track sudden slope variations in the current reference to compensate the distorted current drawn by the voltage source inverter. Therefore, the choice and implementation of the current regulator is more important for the achievement of a satisfactory performance level. In this survey, technical reviews of various types of controllers covering a wide range have been presented. This work also reveals the advantages and disadvantages of the practiced control strategies. The effectiveness of the study will help the researchers to choose the proper control methods for various applicationsof active power filter.Nelinearni tereti pogoršavaju kvalitetu strujnih valova u točki u kojoj se spaja više potrošača. Aktivni filtar snage se koristi za ublažavanje najvažnijeg harmoničkog onečišćenja strujne mreže. Jezgra aktivnog filtra snage je regulator. Na performanse aktivnog filtra snage značajno utječe odabir upravljačke tehnike. Aktivni filtar i njegova tehnika upravljanja strujom moraju imati mogućnost pratiti nagle skokove u referentnoj vrijednosti struje kako bi mogli kompenzirati izobličenja struje koju vuče inverter naponskog izvora. Zato su izbor i implementacija regulatora struje iznimno važni za postizanje zadovoljavajuće razine performansi. U ovom pregledu su predstavljene tehničke recenzije koje pokrivaju širok raspon regulatora. Ovaj rad također otkriva prednosti i mane korištenih strategija upravljanja. Efektivnost ovog pregleda pomoći će istraživačima da izaberu ispravnu metodu upravljanja za različite aplikacije aktivnog filtra snage

Variable-Frequency Grid-Sequence Detector Based on a Quasi-Ideal Low-Pass Filter Stage and a Phase-Locked Loop

This paper proposes a filtered-sequence phase-locked loop (FSPLL) structure for detection of the positive sequence in three-phase systems. The structure includes the use of the Park transformation and moving average filters (MAF). Performance of the MAF is mathematically analyzed and represented in Bode diagrams. The analysis allows a proper selection of the window width of the optimal filter for its application in the dq transformed variables. The proposed detector structure allows fast detection of the grid voltage positive sequence (within one grid voltage cycle). The MAF eliminates completely any oscillation multiple of the frequency for which it is designed; thus, this algorithm is not affected by the presence of imbalances or harmonics in the electrical grid. Furthermore, the PLL includes a simple-frequency detector that makes frequency adaptive the frequency depending blocks. This guarantees the proper operation of the FSPLL under large frequency changes. The performance of the entire PLL-based detector is verified through simulation and experiment. It shows veryPeer ReviewedPostprint (published version

An 'active' passive-filter topology for low power DC/AC inverters

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.This thesis presents a new output passive filter for voltage source inverter applications which is based on a shunt connected single tuned filter topology. The proposed circuit has the advantage of tracing harmonic components wherever its location in the frequency spectrum. The change in the harmonic location might be as a result of a change in the inverter operating frequency. Also, the proposed filter achieves harmonic reduction close to the traditional single tuned passive filter. In order to show the superiority of the proposed model, a comparison is introduced with other self tuning harmonic filters showing merits and drawbacks of each technique. The proposed circuit (when integrated in square wave inverter) has also shown a tremendous reduction in the switching losses in comparison with high frequency Pulse Width Modulation inverter. Mathematical analyses showing the design of the proposed filter together with extensive simulation results to verify the design are also introduced. The practical implementation of the system is presented and the results show excellent agreement with the theory and simulation. In order to appreciate the proposed filter a new method for classifying passive power filters is introduced. The review includes a comparison of these configurations showing their merit and drawbacks

Design of a Two-Stage Level-Two Bidirectional On-Board Battery Charger for Plugin Vehicles

Depletion of fossil fuel reserves, increasing awareness of air pollution levels and continuous rise in gasoline prices are some of the major drives that have been revolutionizing the automotive industry since the last decade. These factors combined are causing conventional automobiles with internal combustion engines (ICE) to be replaced with plugin vehicles. The on-board rechargeable battery packs in plugin vehicles can be recharged by connecting to the utility grid using a plug. The energy stored in the on-board battery packs has attractive benefits for grid support, and this promotes the idea of Vehicle-to-Grid (V2G). V2G power transactions allow energy from the on-board battery packs to be sent back to the utility grid for support in peak shaving and provide reactive power compensation. One natural consequence that arises with the introduction of V2G is a sharp increase in the need for high-performance power electronic interface between the utility grid and the battery pack. Therefore, research on bidirectional battery chargers for plugin vehicles is imperative in order to aid in the promotion of V2G. This thesis focuses on the design and development in a two-stage level-two on-board bidirectional battery charger

Simulation and Experimental Realization of Adaptive Controllers for Shunt Active Power Filter to improve Power Quality

As of late, the demand for electric power is increasing, which has developed a greater demand to maintain a higher level of power quality and continuity of power supply at the consumer end. But increased use of power electronic devices has imperatively degraded the overall power quality of the power system. Due to the non-linear nature of the power electronic devices various current and voltage harmonics are generated, causing harmonic distortion. These harmonics cause various undesirable effects such as equipment heating, nuisance tripping, overheating transformer, data losses, etc. Shunt Active Power Filters are a viable solution to mitigate these harmonics and thus improve the power quality. In this thesis work, various control strategies of shunt active power filter based on voltage and current controller has been presented to mitigate the current harmonics. To extract the three phase reference source current we have developed control algorithm based on Synchronous reference frame theory (id-iq) and Self Tuning Filter. For regulating the DC capacitor bus voltage various voltage controllers such as PI, PID, Fuzzy and Adaptive Fuzzy PID controllers has been developed. While to generate the gate signal of SAPF multiple current controllers such as Hysteresis band current controller, adaptive hysteresis band current controller, weighted adaptive hysteresis band current controller and Lyapunov function based stable current controller has been developed. To analyze their performance, simulation models of these controllers have been developed using Matlab/Simulink for different operating conditions. A complete hardware setup of the three phase shunt active power filter has been developed using dSPACE 1104 to verify the credibility of the proposed controllers