Compensation Of Voltage Sag And Harmonics By Dynamic Voltage Restorer Without Zero Sequence Blocking


Dynamic Voltage Restorer (DVR) is a power electronic gadget to protection delicate stress from voltage hang. Regularly, delicate burdens are electronic-based gadgets which create music. This paper presents soft polar based DVR as voltage hang restorer and sounds compensator without zero succession blocking. Research exhibited in this paper utilizes d-q-0 pivot technique considering of the estimation of unbiased hub, in light of the fact that the strategy works great if the impartial hub esteem is zero. Result demonstrates that this strategy can repay voltage sag and harmonics with a pay blunder of 0.99%. Utilizing this technique, DVR may lessen voltage THD from 10.22% to 0.66%.



 Fig.1 Dynamic voltage restorer



 Fig. 2 Distorted voltages at bus C

Fig. 3 Voltage at bus C after DVR

Fig.4 70% sag at bus C caused by phase-phase-ground fault

Fig.5 70% sag at bus C (caused by phase-phase- ground fault) restored by DVR


The reproduction of a DVR utilizing MATLAB has been introduced. Recreation results demonstrate that DVR can reestablish both the voltage droop and voltage sounds. The proficiency and viability in voltage hang rebuilding and voltage sounds remuneration appeared by the DVR makes it an intriguing force quality gadget contrasted with other custom power gadgets. Under typical condition, DVR can diminish voltage THD from 10.22 % to 0.66%. What’s more, utilizing the proposed strategy, DVR can reestablish hilter kilter voltage droop without zero blocking transformer. The normal mistake of DVR voltage list remuneration is 0.99. voltage sag and harmonics.

Balanced Voltage Sag Correction Using Dynamic Voltage Restorer Based Fuzzy Polar Controller


Numerous controllers based fluffy rationale have been connected on electric power framework. As often as possible, time reaction of the fluffy controllers is gradually, on the grounds that the quantity of participation capacities are too much. Many research are proposed to limit the quantity of enrollment work, for example, fluffy polar controller technique. By utilizing this strategy, number of enrollment capacity can be limited, so the time reaction of the controller turn out to be quicker. This paper displays the Dynamic Voltage Restorer (DVR) based Fuzzy Polar Controller Method to remunerate adjusted voltage list. Reenactment results demonstrate this proposed technique can repay adjusted voltage hang superior to PI controller.



 Fig. 1. Block diagram of DVR


 Fig. 2. 50% of voltage sags at bus A

Fig. 3. 50% sags correction using DVR based PI Controller

Fig. 4. 50% sags correction using DVR based fuzzy polar controller


DVR based PI Controller can keep up half voltage hangs at 110 % and 30% voltage droops at 98%. DVR based Fuzzy Polar Controller can keep up half voltage lists at 100 % and 30% voltage lists at 97%. As per the mistake normal everything being equal, are demonstrated that the execution of DVR based Fuzzy Polar Controller superior to DVR based PI Controller. Further investigation for unbalance remedy is being attempted to demonstrate the viability of the proposed controller.


Multilevel Dynamic Voltage Restorer


This letter exhibits the usage and control of a high voltage dynamic voltage restorer (HVDVR) for use in power conveyance system to adjust for lists in utility voltages. The proposed HVDVR is executed utilizing a staggered inverter topology with secluded dc vitality stockpiles, permitting the immediate association of the HVDVR to the dissemination arrange without utilizing a massive and exorbitant arrangement infusion transformer. A control calculation, consolidating P+resonant and Posicast compensators, is likewise exhibited for controlling the HVDVR with immaculate reference voltage following and powerful damping of transient voltage motions at the moment of droop remuneration. At last, recreation results are displayed to confirm the execution of the proposed staggered HVDVR.



Fig. 1. System configuration with dynamic voltage restoration



Fig.2 Cascaded five-level HVDVR controlled using multi-loop feedback and feedforward control (without Posicast). Top to bottom: v ; v , and v

Fig 3. Cascaded five-level HVDVR controlled using multi-loop feedback and feedforward control (with Posicast). Top to bottom: v ; v , and v

Fig. 4. Cascaded five-level HVDVR switched waveforms. Top to bottom: upper H-bridge voltage, lower H-bridge voltage and resultant inverter voltage

Fig.5. Binary seven-level HVDVR switched waveforms. Top to bottom: upper H-bridge voltage, lower H-bridge voltage and resultant inverter voltage



This letter shows the usage and control of a HVDVR for remunerating utility voltage lists. The HVDVR is actualized utilizing the fell staggered inverter topology with the upsides of enhanced unwavering quality and direct association of the HVDVR to the circulation arrange without the utilization of a massive and expensive arrangement infusion transformer. Other separated inverter topologies can likewise be utilized for indistinguishable reason from exhibited utilizing the twofold inverter, yet the subsequent HVDVR can be less solid under semiconductor disappointment conditions. The fell HVDVR is controlled utilizing a 2-DOF control conspire joining both P full and Posicast compensators, to accomplish immaculate reference voltage following and successful damping of transient voltage motions. The execution of the HVDVR, controlled utilizing diverse control procedures, has been tried broadly in Matlab/Simulink reproduction.

Improving the Performance of Cascaded H-bridge based Interline Dynamic Voltage Restorer


An interline dynamic voltage restorer (IDVR) is another gadget for list relief which is made of a few unique voltage restorers (DVRs) with a typical DC interface, where each DVR is associated in arrangement with a circulation feeder. Amid droop period, dynamic power can be exchanged from a feeder to another and voltage hangs with long terms can be moderated. IDVR pay limit, be that as it may, depends incredibly on the heap control factor and a higher load control factor causes bring down execution of IDVR. To beat this confinement, another thought is displayed in this paper which permits to lessen the heap control factor under hang condition, and hence, the pay limit is expanded. The proposed IDVR utilizes two fell H-connect staggered converters to infuse AC voltage with lower THD and takes out need to low-recurrence disengagement transformers in a single side. The legitimacy of the proposed setup is checked by reproductions in the PSCAD/EMTDC condition. At that point, test results on a downsized IDVR are exhibited to affirm the hypothetical and reproduction results.



Fig. 1 Power circuit schematic of the IDVR with active power exchanging capability.

Fig.2 Proposed IDVR structure.



Fig 3. Investigating the IDVR performance when the proposed method is applied for a sag with depth of 0.4p.u.

Fig 4. Investigating the IDVR performance when the proposed method is applied for a sag with depth of 0.6p.u.



In this paper, another setup has been proposed which not just enhances the remuneration limit of the IDVR at high power factors, yet in addition builds the execution of the compensator to relieve profound droops at genuinely moderate power factors. These points of interest were accomplished by diminishing the heap control factor amid list condition. In this strategy, the source voltages are detected consistently and when the voltage list is recognized, the shunt reactances are exchanged into the circuit and decline the heap control variables to enhance IDVR execution. At last, the recreation and functional outcomes on the CHB based IDVR affirmed the adequacy of the proposed arrangement and control conspire.


Evaluation of a Multilevel Cascaded-Type Dynamic Voltage Restorer Employing Discontinuous Space Vector Modulation


In this paper, the use of a multilevel cascaded inverter as a dynamic voltage restorer (DVR) is explored. Two intermittent staggered space vector regulation (SVM) systems are executed for DVR control and are appeared to diminish inverter exchanging misfortunes while keeping up for all intents and purposes indistinguishable consonant execution from the ordinary staggered SVM at a high number of levels. This paper additionally shows a numerical relationship for registering the bending at the purpose of basic coupling (PCC) as a component of the mutilation of the DVR. This empowers the determination of the quantity of levels required for a specific application. An all-inclusive hang span bolster contrasted with the two-level DVR is another favorable position of the DVR with a multilevel cascaded inverter. The basic mode voltage (CMV) at the PCC has been assessed for the three SVM strategies (the regular staggered SVM and the two spasmodic SVM), introducing a lower CMV for the second broken SVM. A structure precedent is displayed for a 11-kV 5-MVA DVR multilevel cascaded inverter for up to 17 levels, utilizing the ordinary staggered SVM and the two irregular SVM methods.



Fig. 1 Proposed DVR in a distribution system.



Fig.2 Load and DVR voltages employing conventional SVM.

Fig 3. Load and DVR voltages employing DB1 SVM.

Fig. 4. Load and DVR voltages employing DB2 SVM.

Fig.5. Load and DVR voltages employing conventional SVM at L = 1 mH.

Fig.6 Load and DVR voltages employing conventional SVM at L = 0 mH.



Notwithstanding encouraging transformer-less DVR task and decreasing separating necessities with the staggered DVR, contrasted with the two-level DVR, the primary commitment of this paper, to the DVR staggered fell inverter, can be condensed as pursues.

1) Reduced exchanging misfortunes can be acquired utilizing broken SVM while keeping up for all intents and purposes indistinguishable consonant execution from the traditional staggered SVM at a high number of levels.

2) The staggered DVR consonant execution has been assessed from the perspective of PCC up to 17 levels for various voltage droop profundities (beforehand, the consideration has been arranged to assess the DVR yield voltage symphonious execution).

3) Multilevel fell sort DVR can bolster an all-encompassing list length contrasted with the two-level DVR.

4) The CMV at the PCC has been assessed for the three SVM systems (the customary staggered SVM and the two intermittent SVM) for up to 17 levels and for various droop profundities, exhibiting a lower CMV for the second spasmodic SVM. The principal broken SVM method presents the most astounding CMV.

Operation and Control of a Dynamic Voltage Restorer Using Transformer Coupled H-Bridge Converters


The dynamic voltage restorer (DVR) as a methods for arrangement remuneration for relieving the impact of voltage lists has turned out to be built up as a favored methodology for enhancing power quality at delicate load areas. In the mean time, the fell staggered kind of intensity converter topology has additionally turned into a workhorse topology in high power applications. This paper exhibits the nitty gritty structure of a shut circle controller to keep up the heap voltage inside adequate dimensions in a DVR utilizing transformer coupled H bridge converters. The paper presents framework task and controller configuration approaches, checked utilizing PC reproductions, and a research center scale exploratory model.




Fig. 1 Interconnection schematic of (a) series and (b) shunt compensation configurations

for power quality improvement.


Fig.2 Simulation results for balanced sag. From top to bottom traces are grid voltage, positive sequence of grid voltage, negative sequence of grid voltage, injected voltage, and load voltage.

Fig 3. Simulation results for unbalanced sag. From top to bottom traces are grid voltage, positive sequence of grid voltage, negative sequence of grid voltage, injected voltage, and load voltage.



This paper has exhibited the acknowledgment and control highlights of a DVR utilizing an air conditioner stacked staggered converter with fell H bridge converters. The power circuit engineering has been talked about pursued by a model advancement prompting the controller plan. The framework is displayed in the synchronous reference outline representing positive and negative succession voltage hangs to be alleviated. The multi-circle controller with complex state criticism decoupling is structured with an inward current circle and external voltage circle. The controller highlights strong structure edges, incredible yield impedance, and line direction as outlined utilizing recurrence reaction predications. Point by point numerical reproduction has been completed to check the power circuit activity and control plot. A research facility scale test model was produced that checks the power circuit task and controller execution. Test results demonstrate superb concurrence with advanced reenactments.

Artificial Neural Network (ANN) based Dynamic Voltage Restorer for Improvement of Power Quality


Dynamic Voltage Restorer (DVR) is a custom power gadget utilized as a successful arrangement in shielding touchy burdens from voltage aggravations in power dissemination frameworks. The productivity of the control system, that directs the exchanging of the inverters, decides the DVR effectiveness. Corresponding Integral-Derivative (PID) control is the general method to do that. The power quality rebuilding capacities of this controller are constrained, and it produces critical measure of music – all of which comes from this straight procedure’s application for controlling non-direct DVR. As an answer, this paper proposes an Artificial Neural Network (ANN) based controller for improving rebuilding and sounds concealment abilities of DVR. A point by point examination of Neural Network controller with PID driven controller and Fuzzy rationale driven controller is additionally represented, where the proposed controller exhibited unrivaled execution with a unimportant 13.5% Total Harmonic Distortion.



Fig. 1 Simulation model for sag mitigation with ANN controller.



Fig.2 Three phase sag mitigation based on ANN controlled DVR. (a) Instantaneous voltage at stable condition; (b) Instantantaneous voltage when sag occurs; (c) Voltage required to mitigate voltage sag; (d) Output voltage of the inverter circuit; (e) Generated PWM for inverter; (f) Instantaneous voltage after voltage restoration.

Fig 3. Restored Voltage Using (a) PID controller; (b) Fuzzy controller; (c) ANN controller; (d)THD comparison: the least THD can be seen at ANN based DVR, the range of the harmonics is also truncated by a huge amount by this method.



DVRs are a famous decision for upgrading power quality in power frameworks, with a variety of control framework on offer to drive these gadgets. In this paper, utilization of ANN to work DVR for giving preferable execution over existing frameworks to relieve voltage list, swell, and music has been illustrated. Issue articulation and hypothetical foundation, structure of the proposed strategy, preparing system of the ANN utilized have been portrayed in detail. Recreation results demonstrating the DVR execution amid voltage droop have been exhibited. Examination of the proposed technique with the well known PID controller, and nonlinear Fuzzy controller has been completed, where the proposed ANN controller showed up as the best choice to reestablish framework voltage while alleviating THD to the best degree.

DVR with Fuzzy Logic Controller and Photovoltaic for Improving the Operation of wind farm


Wind control is a standout amongst the most imperative sort of sustainable power sources. Wind cultivate as a gadget which gets this vitality needs some exceptional conditions to work appropriately. The most widely recognized kind of wind turbine is the variable-speed straightforwardly associated with the matrix. Blames in the power framework can begin the detachment of wind ranches. Dynamic voltage reestablish (DVR) is a custom power gadget utilized for disposing of voltage sages and swells which is the aftereffect of the issues. This paper exhibits a reproduction model of a 12-beat DVR utilizing photovoltaic (PV) as a mean of giving an elective vitality source to the DVR. In this examination, the plan of a fluffy rationale (FL) controlled DVR are exhibited and reached out to perform quick blame identification. Another control technique for DVR is proposed by consolidating FL with a bearer adjusted PWM inverter. Recreations were completed utilizing the MATLAB SIMULINK. The recreation results demonstrated the ability of PV-based DVR in wiping out voltage droop and swell disseminated framework. Enhancing the task of wind cultivate as a vitality generator and balancing out its voltage is the principle consequence of this work.



Fig 1 General system



Fig. 2 supply voltage in swell condition

Fig.3 DVR injection voltage in swell condition

Fig.4 wind farm voltage in swell condition after compensation

Fig.5. supply voltage in sag condition

Fig.6 DVR injection voltage in sag condition

Fig.7 wind farm voltage after compensation

Fig.8. Wind farm current after compensation (in both sag and swell condition)



In this paper, A 12-beat DVR is planned and through utilizing new control technique all voltage hangs and swells in the circuit is commonly redressed. For this situation the terminal voltage which is associated with the breeze turbine remain consistent and in spite of the voltage flimsiness in system wind generators will have the capacity to stay associated with the system and work in stable condition through utilizing DVR. In this article we could remunerate an appropriation frameworks when droop and swell voltages happen in an exact and controlled way. This controlling strategy depends on fluffy control which is mimicked by Matlab/Simulink programming. Additionally in this paper to give a wellspring of DC DVR we have utilized PV which is a sort of normal vitality source. The reproduction results affirm all.

Voltage Sag/Swell Compensation Using Z-source Inverter DVR based on FUZZY Controller


The power quality necessity is one of the serious issues for power organizations and their clients. The examination of intensity unsettling influence attributes and discovering answer for the power quality issues have brought about an expanded enthusiasm for power quality. The most concerning aggravations influencing the nature of the power in the conveyance framework are voltage list/swell. The DVR is utilized to alleviate the voltage list/swell on touchy load. In this paper Z-source inverter (ZSI) based DVR is proposed to improve the voltage rebuilding property of the framework. The ZSI utilizes a LC impedance lattice to couple control source to inverter circuit and readies the likelihood of voltage buck and lift by shortcircuiting the inverter legs. Furthermore a fluffy rationale control plot for Z-source inverter based DVR is proposed to acquire wanted infusing voltage. Displaying and reproduction of the proposed DVR is actualized in MATLAB/SIMULINK stage.



Fig. 1 DVR general configuration



Fig.2Three phase voltage at load point during three phase fault without DVR

Fig 3. Three phase voltage by DVR

Fig.4Three phase compensated voltage with DVR

Fig.5comparison of performance of DVR using Z-source inverter during fault condition

Fig.6Three phase voltage at load point during three phase fault with DVR and PI controller

Fig.7Three Phase voltage at load point during three phase fault with DVR and PI and Fuzzy controller



DVR fills in as a successful custom power gadget for relieving voltage hang/swell in the dispersion framework. If there should arise an occurrence of outside aggravations the proposed DVR infuses suitable voltage part to powerfully address any deviation in supply voltage so as to keep up adjusted and steady load voltage at ostensible esteem. In this paper Z – source inverter based DVR alongside fluffy controller is displayed and the equivalent is introduced in the conveyance framework to give required load side pay. The reenactment of the DVR alongside the proposed controller is completed utilizing MATLAB/SIMULINK stage. The reenactment results demonstrates that the execution of Z – source inverter based DVR alongside fluffy controller is better contrasted with PI controller.

Performance Investigation of Dynamic Voltage Restorer using PI and Fuzzy Controller


This paper researches the execution of Dynamic Voltage Restorer for repaying distinctive voltage droop levels with different flaws and to lessen the Total Harmonic Distortion amid the alleviation procedure. The DVR is actualized with three stage voltage source inverter and is associated at the purpose of normal coupling so as to direct the heap side voltage. The pay depends on PI and Mamdani Fuzzy Controller. Broad reproduction examines under various size of hang for flaws on load side for adjusted and lopsided conditions are directed utilizing shortcoming generator. Reenactment result investigation uncovers that DVR performs consummately with PI and Fuzzy control approach. What’s more, ability and execution of DVR for different vitality stockpiling limits and infusion transformer rating are additionally broke down. The execution of these controllers is approved with recreation results utilizing Matlab/Simulink.



Fig. 1. Block Diagram of DVR model



Fig.2 Unbalanced three-phase to ground fault (PI CONTROL)

Figure 3. Unbalanced three-phase to ground fault (FLC)

Fig.4 Single-line-to-ground fault with 50% sag (PI Control)

Fig.5 Single-line-to-ground fault with 50% sag (FLC)

Fig.6 Balanced three-phase fault with 50% sag (PI CONTROL)

Fig.7 Balanced three-phase fault with 50% sag (FLC)

Fig.8 Three Phase fault with nearly 100% sag (PI)

Fig.9 Three Phase fault with nearly 100% sag (FLC)



The DVR handles both adjusted and uneven conditions viably and infuses the digressed voltage part under supply unsettling influences to keep the heap voltage adjusted and consistent at the ostensible esteem. In this manner the proposed DVR can alleviate different dimensions of voltage hang and distinctive sorts of shortcomings. Reenactment results in MATLAB/SIMULINK demonstrate that the control conspire gives a precise following of the voltage reference and a quick transient reaction. Both the controllers shows great execution and limit the THD level. It is discovered that FLC gives better execution with THD of 0.42% where as PI gives 0.46% THD. The expansion in KVA rating of infusion transformer and DC stockpiling esteem successfully repays the voltage droop and diminish the THD level. Be that as it may, higher estimation of DC stockpiling and transformer rating makes it increasingly costly. The adequacy of a DVR framework basically relies on the rating of DC stockpiling limit, infusion transformer rating and the heap. From the recreation, it obviously demonstrates the significance of these components and how it influences the execution of DVR is dissected.