Design of an Efficient Dynamic Voltage Restorer for Compensating Voltage Sags, Swells, and Phase Jumps

ABSTRACT:  

This paper presents a novel design of a dynamic voltage restorer (DVR) which mitigate voltage sags, swell and phase jumps by injecting minimum active power in system and provides the constant power at load side without any disturbance. The design of this compensating device presented here includes the combination of P WM-based control scheme, d q 0 transformation and PI controller in control part of its circuitry, which enables it to minimize the power rating and to response promptly to voltage quality problems faced by today’s electrical power industries.

An

immense knowledge of power electronics was applied in order to design and model of a complete test system solely for analyzing and studying the response of this efficient DVR. In order to realize this control scheme of DVR MAT LAB/SIM U LINK atmosphere was used. The results of proposed design of DVR’s control scheme are compared with the results of existing classical DVR which clearly demonstrate the successful compensation of voltage quality problems by injecting minimum active power.

BLOCK DIAGRAM:

 

 Fig.1. Block Diagram of DVR

 EXPECTED SIMULATION RESULTS:

 

Fig.2.Source Voltage with Sag of 0.5 p.u.

Fig.3.Load Voltage after Compensation through proposed DVR

Fig.4. Load Voltage after Compensation through classical DVR

Fig.5. Voltage injected by proposed DVR as response of Sag

Fig.6.Source Voltage with Swell of 1.5 p.u.

Fig.7. Load Voltage after compensation through proposed DVR

Fig.8. Load Voltage after Compensation through classical DVR

Fig.9. Voltage injected by DVR as response of Swell

Fig.10. .Load Voltage after Compensation of Phase jump

Fig.11. d q 0 form of difference voltage obtained by proposed DVR

Fig.12. d q 0 form of difference voltage obtained by classical DVR

CONCLUSION:

As the world is moving towards modernization, the most essential need that it has is of an efficient and reliable power of excellent quality. Nowadays, more and more sophisticated devices are being introduced, and their sensitivity is  dependent upon the quality of input power. Because even a slight disturbance in power quality, such as Voltage sags, voltage swells, and harmonics, which lasts in tens of milliseconds, can result in a huge loss because of the failure of end use equipment s. For catering such voltage quality problems an efficient DVR is proposed in this paper with the capability of mitigating voltage sags, swells, and phase jumps by injecting minimum active power hence decreasing the VA rating of DVR.

REFERENCES

[1] K u m  a r, R. A nil, G. Siva K u mar, B. K a l y an K u mar, and Ma he sh K. Mi s h  R a. “Compensation of voltage sags and harmonics with phase jumps through DVR with minimum VA rating using Particle Swarm Optimization.” In Nature & Biologically Inspired Computing, 2009. NaBIC 2009. World Congress on, pp. 1361-1366. IEEE, 2009.
[2] Song song, Chen, Wang Jian wei, Ga o Wei, and Hu Xiaoguang. “Research and design of dynamic voltage restorer.” In Industrial Informatics (INDIN), 2012 10th IEEE International Conference on, pp. 408-412. IEEE, 2012.
[3] A. Bendre, D. Divan, W. Kranz, and W. E. Brumsickle, “Are Voltage Sags Destroying Equipment?,” IEEE Industry Applications Magazine, vol. 12, pp. 12-21, July-August 2006.

 

Modeling And Simulation For Voltage Sags/Swells Mitigation Using Dynamic Voltage Restorer (Dvr)

ABSTRACT

 This project describes the problem of voltage sags and swells and its severe impact on non linear loads or sensitive loads. The dynamic voltage restorer (DVR) has become popular as a cost effective solution for the protection of sensitive loads from voltage sags and swells. The control of the compensation voltages in DVR based on dqo algorithm is discussed. It first analyzes the power circuit of a DVR system in order to come up with appropriate control limitations and control targets for the compensation voltage control. The proposed control scheme is simple to design. Simulation results carried out by Matlab/Simulink verify the performance of the proposed method .

KEYWORDS

  1. DVR
  2. Voltage sags
  3. Voltage swells
  4. Sensitive load

 

SOFTWARE: MATLAB/SIMULINK

BLOCK DIAGRAM

 DVR

Figure 1: Schematic diagram of DVR

 

FLOWCHART:

  

Fig.2 Flow Chart Of Feed forward Control Technique For DVR Based Ob DQO Transformation

Three-phase voltages sag:

Figure 3. Three-phase voltages sag: (a)-Source voltage,(b)-Injected voltage, (c)-Load voltage

Single-phase voltage sag

Figure.4. Single-phase voltage sag: (a)-Source voltage, (b)-Injected voltage, (c)-Load voltage

Three-phase voltages swell

Figure.5.Three-phase voltages swell: (a)-Source voltage, (b)-Injected voltage, (c)-Load voltage

Two-phase voltages swell

Figure. 6. Two-phase voltages swell: (a)-Source voltage, (b)-Injected voltage, (c)-Load voltage

 

CONCLUSION:

 The modeling and simulation of a DVR using MATLAB/SIMULINK has been presented. A control system based on dqo technique which is a scaled error of the between source side of the DVR and its reference for sags/swell correction has been presented. The simulation shows that the DVR performance is satisfactory in mitigating voltage sags/swells.

 

REFERENCES:

  • G. Hingorani, “Introducing Custom Power in IEEE Spectrum,” 32p, pp. 4l-48, 1995.
  • IEEE Std. 1159 – 1995, “Recommended Practice for Monitoring Electric Power Quality”.
  • Boonchiam and N. Mithulananthan, “Understanding of Dynamic Voltage Restorers through MATLAB Simulation,” Thammasat Int. J. Sc. Tech., Vol. 11, No. 3, July-Sept 2006.
  • G. Nielsen, M. Newman, H. Nielsen,and F. Blaabjerg, “Control and testing of a dynamic voltage restorer (DVR) at medium voltage level,” IEEE Trans. Power Electron., vol. 19, no. 3,p.806, May 2004.
  • Ghosh and G. Ledwich, “Power Quality Enhancement Using Custom Power Devices,” Kluwer Academic Publishers, 2002.
  • Modeling And Simulation For Voltage Sags/Swells Mitigation Using Dynamic Voltage Restorer (Dvr)