Three-Phase Shunt Active Power Filter for Power Improvement Quality using Sliding Mode Controller

ABSTRACT:

In this paper, experimental study of Sliding Mode Controller (SMC) DC bus voltage of three phase shunt active power filter (APF), to improve power quality by compensating harmonics and reactive power required by nonlinear load is proposed. The algorithm used to identify the reference currents is based on the Self Tuning Filter (STF). For generation of the pulse switching of the IGBTs inverter the hysteresis current controller is used, implemented into an analogue card. Finally, various experimental results are presented under steady state and transient conditions.

KEYWORDS:

1.      Shunt Active Power Filter (APF)

2.       Total Harmonic Distortion (THD)

3.       Sliding Mode Controller (SMC)

4.      Self Tuning Filter (STF)

SOFTWARE: MATLAB/SIMULINK

 BLOCK DIAGRAM:

\

Fig. 1: The basic compensation principle of the shunt APF.

 EXPECTED SIMULATION RESULTS:

\

Fig. 2. Experimental APF results: load current iL (A), filter current iF (A)

and source current iS (A). Ch1 to Ch4 scale: 5 A/div. Time scale: 20 ms/div.

\

Fig. 3. Experimental APF results: load current iL (A), filter current iF (A),

source current iS (A) and source voltage Vs (V). Ch1 and Ch3 scale: 5 A/div;

Ch2 scale: 100 V/div;Ch4 scale: 80 V/div; Time scale: 10 ms/div.

\

Figure 4. Experimental APF results : load current iL(A), filter current iF(A) ,

source current iS(A) and DC voltage Vdc(V). Ch1,Ch3 and Ch4 scale: 10

A/div. Ch2 scale: 100 V/div. Time scale: 20 ms/div.

\

Figure 5. Experimental APF results: DC voltage Vdc (V) and DC reference

voltage V*dc (V). Ch1 and Ch2 scale: 100 V/div. Time scale: 1s/div

CONCLUSION:

The control of the shunt Active Power Filter was divided in three parts, the first one realized by the dSPACE system to generate the reference currents, the second one achieved by an analogue card for the switching pattern generation, implementing a hysteresis current controller and the third party use a sliding mode controller SMC. A SMC controlled shunt active power filter has been studied to improve the power quality by compensating both harmonics and reactive power requirement of the nonlinear load. The performance of the SMC controller has been developed in real time process and successfully tested in the laboratory The results of experiment study of APF control technique presented in this paper are found quite satisfactory to eliminate harmonics and reactive power components from utility current. The shunt APF presented in this paper for the compensation of harmonic current components in non-linear load was effective for harmonic isolation and keeping the utility supply line current sinusoidal. The validity of this technique was proved on the basis of experiment results. The APF is found effective to meet IEEE- 519-1992 standard recommendations on harmonics levels.

REFERENCES:

[1] Chaoui; J.P.Gaubert; F.Krim; G.Champenois, “PI Controlled Threephase Shunt Active Power Filter for Power Quality Improvement” A. “Electric Power Components and Systems, 1532-5016, Volume 35, Issue 12, 2007, Pages 1331 – 1344.

[2] D. Benatous, R. Abdessemed, “Digital voltage control of AC/DC PWM Converter with improved power factor and supply current ”, Journal of electric machines and power systems, Taylor and francis, 2000.

[3] G. A. Capolino, A. Golea, H. Henao, “Système de réduction des perturbations réseau pour commande vectorielle ”, Proc. Colloque SEE Perturbations Réciproques des Convertisseurs et des Réseaux, Nantes, 6 juillet 1992.

[4] M. Abdusalam, P. Poure and S. Saadate,’’ A New control scheme of hybrid active filter using Self-Tuning Filter,’’ POWERENG, International Conference on Power Engineering , Energy and Electrical Drives, Setubal Portugal,12-14 April (2007).

[5] M. Abdusalam, P. Poure and S. Saadate, « Study and experimental +6validation of harmonic isolation based on Self-Tuning-Filter for threephase active filter ». ISIE, IEEE International Symposium on Industrial Electronics, Cambridge, UK, (2008).

Performance Improvement of Active Power Filters based on P-Q and D-Q Control Methods under Non-Ideal Supply Voltage Conditions

ABSTRACT:

In this paper, we investigate the effect of unbalanced and distorted supply voltages on the performance of active power filters that are based on the well-known p-q and d-q control methods. Our analysis shows that the harmonic suppression performance of the p-q and d-q control methods deteriorates when non-ideal sources are used. We propose the use of a self tuning filter (STF) with the p-q theory or d-q method as a way of alleviating the detrimental effects of non-ideal supply voltages. Simulation results show that the proposed method can improve the performance of active power filters under non-ideal voltage conditions.

 SOFTWARE: MATLAB/SIMULINK

 BLOCK DIAGRAM:

Fig.1.Block diagram of simulated APF

EXPECTED SIMULATION RESULTS: 

Fig.2 Three phase balanced and undistorted (ideal) source voltage

Fig.3. Supply currents with p-q method under case 1. (THDi=2.1%)

Fig.4. Supply currents with d-q method under case 1. (THDi=2.07)

Fig.5. Distorted and unbalanced source voltages for case 2.

Fig.6. Supply currents with p-q method under case 2.

Fig.7. Supply currents with d-q method under case 2.

Fig.8. Supply currents with STF based p-q method under case 3.

Fig.9. Supply currents with STF based d-q method under case 3.

CONCLUSION:

In this paper, we consider the effect of an unbalanced and distorted supply on the performance of the well-known p-q theory and d-q methods for active power filters. The ability of these methods to combat current harmonics deteriorates significantly when a non-ideal supply voltage is used. A modification to the p-q and d-q methods is then proposed for alleviating the effects of an imperfect supply. This involves the use of a self-tuning filter (STF) with p-q theory and the d-q method. We show that the total harmonic distortion of source current (THDi) can be reduced by up to around 2.30 % with the use of a STF under non-ideal voltage conditions. In addition, our comparative results show that an STFbased d-q method performs better than an STF-based p-q theory.

REFERENCES:

[1] W. Mack Grady, S. Santoso, "Understanding power system harmonics", IEEE Power Eng. Rev. 21 (November (11)) (2001) 8-11.

[2] S. Biricik, O. C. Ozerdem "Investigation of Switched Capacitors Effect on Harmonic Distortion Levels and Performance Analysis with Active Power Filter", Przeglad Elektrotechniczny, ISSN 0033-2097, R. 86 NR 11a/2010, pp 13-17.

[3] S. Buso, L. Malesani, P. Mattavelli, "Comparison of current control techniques for active filter applications," Industrial Electronics, IEEE Transactions on , vol.45, no.5, pp.722-729, Oct 1998.

[4] H. Akagi, Y. Kanazawa, A. Nabae, "Generalized Theory of the Instantaneous Reactive Power in Three-Phase Circuits", IPEC'83- Int. Power Electronics Conf., Tokyo, Japan, 1983, pp. 1375-1386.

[5] M. Asadi, A. Jalilian, H. F. Farahani, "Compensation of Unbalanced Non Linear Load and neutral currents using stationary Reference Frame in Shunt Active Filters," Harmonics and Quality of Power (ICHQP), 2010 14^th International Conference on, vol., no., pp.1-5, 26-29 Sept. 2010.

Multiple - Input Bidirectional DC -DC Power Converter with Renewable Energy Source

ABSTRACT:

A novel multiple–input converter with bidirectional power flow capability is proposed in this paper. By using bidirectional power flow approch, not only the buck mode but also the boost mode of operation can be possible. Moreover, by establishing single power converter for different sources we can reduce the components and so the size of overall system and cost can be reduced. In this topology independent of voltage level interconnection of voltage sources can be possible. One of the source used is solar panel which holds the predominant place for satsfying the futur enegry demand. In fuel cell vehicles different sources which having unequal voltage rating is needed with bidirectional power flow. Thus the proposed topology finds application in fuel cell vehicles (FCVs)/hybrid electric vehicles (HEVs).The operation principle, theoretical analysis, and design of the proposed converter are presented in this paper. Simulation results are used to verify both the exactness and feasibility of the proposed converter.

KEYWORDS:

1.      DC –DC power converter

2.       Multiple input converter

SOFTWARE: MATLAB/SIMULINK

 BLOCK DIAGRAM:

Fig. 1. Functional block diagram of a FCV system

EXPECTED SIMULATION RESULTS:

Fig. 2. Simulation result of mode E inductor currents, voltages and dc link current

Fig. 3. Simulation result of mode F inductor currents, voltages and

dc link current

Fig. 4. Simulation result of mode G inductor currents, voltages and

dc link current

CONCLUSION:

This paper has proposed a multiple-input bidirectional dc–dc converter to interface more than two sources of power/energy operating at different voltage levels. The converter can be operated either in buck mode or boost mode in either directions of power flow. It is possible to control the power flow between each pair of sources independently when more than two sources are active. This paper gives detailed analysis and operation of the converter for various modes. In each mode, the relationship between the sources is derived which assists in the implementation of the controller. Simulations are done with three sources. Results obtained from these systems have been presented and match very well with the analytically expected waveforms. This converter not only finds application in FCVs but also can be utilized in distributed energy resources, smart grid and microgrid, battery management systems, etc., where more than two dc sources need to be interfaced with bidirectional power flow capability

REFERENCES:

[1] S. Aso, M. Kizaki, and Y. Nonobe, “Development of hybrid fuel cell vehicles in Toyota,” in Proc. IEEE PCC, 2007, pp. 1606–1611

[2] K. Rajashekhara, “Power conversion and control strategies for fuel cell vehicles,” in Proc. IEEE IECON, 2003, pp. 2865–2870.

[3] C. Chan, “The state of the art of electric and hybrid vehicles,” Proc. IEEE, vol. 90, no. 2, pp. 247-275, Feb. 2002

[4] B. Ozpineci, L. M. Tolbert, D. Zhong, “Multiple input converters for fuel cells,” in proc. Industry Applications Conference, 2004, vol. 2, pp. 791-797, 3-7 Oct. 2004

[5] Y.M. Chen, Y.C. Liu, and S.H. Lin, “Double-input PWM DC-DC converter for high/low voltage sources,” 25th International Telecommunications Energy Conference, 19-23 Oct. 2003, pp. 27–32.

Three-Phase For-Wire Shunt Active Filter With Unbalanced loads

ABSTRACT:

The electrical power quality at low voltage alternative networks became a serious concern because of the increased use of nonlinearloads and pollutants. This work is to improve the quality of electric current in such networks. Four-Wire Shunt Active Filter is studied; deferent loads (balanced and unbalanced) are discussed. We propose to identify harmonic and reactive currents at the base of Self-Tuning-Filters, which proved very good filtering performance, either in transient or steady state. The simulations demonstrate the importance of this work in harmonic filtering and reactive power compensation.

KEYWORDS

1.      Shunt Active Filter (SAF)

2.      Total Harmonic Distortion(THD)

3.      Self-Tuning-Filter (STF)

4.      Unbalanced loads

SOFTWARE: MATLAB/SIMULINK

 BLOCK DIAGRAM:

Fig. 1. Block diagram of the APF

 EXPECTED SIMULATION RESULTS:

                                            Fig.2 Simulation results of STFs under three balanced loads:

(a) Supply and loads currents, (b) 1st phase filter current, (c) Neutral currents,

(d) Harmonic current spectre of 1st phase load, (e) Harmonic current spectre of 1st phase of supply

 Fig.3 Simulation results under three unbalanced loads:

(a) Source and loads currents, (b) Neutral currents, (c) Filter currents,(d) Harmonic currentspectres of loads,(e) Harmonic current spectres of supply

                         

Fig.4 Supply voltage and current (phase 1)

CONCLUSION:

In this paper we have presented a new tree-phase for-wire active power filter based on STF extraction, to identifyharmonic current and reactive power. The objective was to improve the dynamic of identification method and also selectivity. The advantages of this filter are: STFs don’t introduce any displacement between input and output, at the fundamental pulsation. Good dynamic,and high selection of fundamental signal. Their selectivity is improved by reducing K. They can filtrate the voltages that are used to calculate instantaneous powers, to identify perturbation, and so PLL is not used. This method reduces the complexity of the control scheme and consequently facilitates the digital implementation of the control system. Those results demonstrate the good performances of the proposed control.

REFERENCES:

[l] M. Abdusalam, P. Poure,S. Saadate, “Hardware Implementation of a Three-PhaseActive Filter System with HarmonicIsolationBased on Self-Tuning-Filter”, IEEE. Power Electronics Specialists Conference, Aug. 2008, pp. 2276-2278.

[2] M. Abdusalam, P. Poure, S. Saadate, “A New Control Method of Hybrid Active Filter to Eliminate the 5th and 7th Harmonic Frequency Using Self-Tuning-Filter in the Feedforward Loop”. IREE, International Review of Electrical Engineering, Feb. 2008, pp. 65-72.

[3] A Ghamri, M.T Benchouia, A.Golea.,Sliding-mode Control Based Three-phase Shunt Active Power Filter: Simulation and Experimentation; Electric Power Components and Systems Journal, 2012, 40( 4): 383-398.

[4] M. Abdusalam, P. Poure, S. Saadate, “A New ControlScheme of Hybrid Active Filter Using Self-Tuning Filter”, POWERENG, International Conference on Power Engineering , Energy and Electrical Drives, Setubal Portugal,April. 2007, pp. 12-14.

[5] M.C. Benhabib, S. Saadate, “ New Control Approach for Four-Wire Active Power FilterBasedon the Use of Synchronous Reference Frame”,Elsevier B.V. Electric Power Systems Research 73,Nov. 2004, pp. 353–362. .

Real-time control of shunt active power filter under distorted grid voltage and unbalanced load condition using self-tuning filter

ABSTRACT:

In this paper, an alternative control method is proposed to improve the harmonic suppression efficiency of the activepower filter in a distorted and an unbalanced power system to compensate for the perturbations caused by the unbalanced nonlinear loads. The proposed method uses a self-tuning filter (STF) to process the grid voltage in order to provide a uniform reference voltage to obtain the correct angular position of the phase locked loop. Moreover, the required compensation currents are obtained by implementing another STF in the transformed set of currents in order to separate the fundamental and the harmonic currents. This allows the calculation of a precise reference current for the unbalanced, the non-linear and the variable load conditions. The proposed control method gives an adequate compensating current reference even for a nonidealvoltage and unbalanced current conditions. The real-time control of the filter under the distorted and the unbalanced power system is developed in an RT-LAB real-time platform. The results obtained in the software-in-the-loop configuration are presented to verify the effectiveness of the proposed control technique.

 

SOFTWARE: MATLAB/SIMULINK

 BLOCK DIAGRAM:

Fig. 1 Block diagram of the APF and the proposed control method

 EXPECTED SIMULATION RESULTS:

Fig. 2 Voltage and the current waveforms

a Ideal grid voltage

b Non-ideal (distorted and unbalanced) grid voltage

c Load currents under the ideal grid voltage

d Load currents under the non-ideal grid voltage

Fig. 3 Compensation of the grid current harmonics by using the conventional dq method

a Under the ideal voltage

b Under the non-ideal voltage, and by using the conventional pq method

c Under the ideal voltage

d Under the non-ideal voltage

Fig. 4 Compensation of the grid current harmonics

a By using the STF-based pq theory under the ideal voltage

b By using the STF-based pq theory under the ideal voltage

c By using the proposed method under the ideal voltage

d By using the proposed method under the non-ideal voltage

CONCLUSION:

In this paper, the design of a control method that generates thecorrect reference current signal in order to satisfy the requirements of a harmonic suppression and a reactive power compensation, for the unbalanced non-linear load combinations under the case of the non-ideal grid voltageconditions have been discussed. An alternate method is proposed where two STF are applied to manage the distorted and the unbalanced voltage and current. In the proposed method, the distorted and the unbalanced voltages are first processed by using the STF to determine the correct angular positions. Then, a second STF is used toextract the balanced load current waveforms. This methodeliminates the need for additional low-pass or high-pass filtering when extracting the harmonic components from the fundamental. A step-by-step performance study, in a real-time environment, shows that the proposed control technique is able to generate the proper compensating reference current during the steady state and the dynamic load change conditions under the distorted and the unbalanced grid voltage conditions.

REFERENCES:

1 Sasaki, H., Machida, T.: ‘A new method to eliminate AC harmoniccurrents by magnetic flux compensation-considerations on basic design’, IEEE Trans. Power Appar. Syst., 1971, PAS-90, (5), pp. 2009–2019

2 Gyugyi, L., Strycula, E.C.: ‘Active AC power filters’. Proc. IEEE Ind. Appl. Ann. Meeting, 1976, vol. 19-C, pp. 529–535

3 Singh, B., Al-Haddad, K., Chandra, A.: ‘A review of active filters for power quality improvement’, IEEE Trans. Ind. Electron., 1999, 46, (5), pp. 960–971

4 Mariun, N., Alam, A., Mahmod, S., Hizam, H.: ‘Review of control strategies for power quality conditioners’. National Power and Energy Conf. Proc., PECon 2004, 29–30 November 2004, pp. 109–115

5 Akagi, H., Kanazawa, Y., Nabae, A.: ‘Instantaneous reactive power compensators comprising switching devices without energy storage components’, IEEE Trans. Ind. Appl., 1984, IA-20, (3), pp. 625–630