REACTIVE POWER COMPENSATION USING STATCOM

PRESENTED BY NEHA L. JAIN CB.EN.U4EEE13034

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OBJECTIVE• What is Power Quality• Why Reactive Power Compensation is needed• Introduction to STATCOM and its working • How STATCOM helps in increasing the reliability of power supply from the utility grid – using MATLAB/SIMULINK results

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POWER QUALITY • Availability of Reliable Power required for proper operation of all end user equipments• Power Quality disturbance is defined as any change in Power, Voltage, Current or Frequency that interferes with the normal operation of the electrical equipment[4]• Most commonly faced power quality issues are Transients Undervoltage / Sag Overvoltage / Swell Harmonic distortion

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WHY REACTIVE POWER COMPENSATION ?• Energy storage elements

(Inductor/Capacitor) requires Reactive Power (Q) for their operation

• Most of the loads are inductive in nature

• Q reduces Power Factor, and hence increases current flow through the line for the same required active power

• Also Q reduces the voltage at the receiving end

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BENEFITS OF REACTIVE POWER COMPENSATIONReduced tariff

(penalty for excessive Q consumption)

Improved efficiency

Improved voltage regulation

Better performance of the Power System on the whole

5Figure 1: Power Triangle

INTRODUCTION TO FACTS• FACTS (Flexible Alternating current Transmission System) refers to a family of power electronics based devices to enhance the AC system controllability and stability and to increase power transfer capability[5]

• FACTS Controllers are broadly classified into two types Series controllers Shunt controllers• Series controllers – inject voltage in series with the transmission line• Shunt controllers – inject current into the transmission line

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STATCOM STATCOM - Static Synchronous Compensators • Shunt Controller • Can either provide or absorb Reactive power• Uses force – commutated power electronic devices like GTO, IGBT• Mostly applied in long transmission lines and are useful for many purposes namely Power Factor Correction Voltage support and control Harmonic suppression 7

FUNCTIONAL DIAGRAM OF STATCOM

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COUPLING TRANSFORMERVAC

VSC

VOUTIAC

CDC

VDCIDC

BUS

Figure 2: Diagram of STATCOM

VOLTAGE SOURCE CONVERTER

9Figure 3: Circuit diagram of VSC

OPERATION OF STATCOM• Principle: Two AC sources of same frequency

when connected through a series inductance, Reactive power flows from higher voltage magnitude to lower voltage magnitude

• When voltage angle changes, Real Power flows

• When voltage magnitude changes, Reactive Power flows

• Control schemes for STATCOM Direct control scheme Indirect control scheme

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SIMULATION – WITHOUT STATCOM

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Figure 4: Simulink model without STATCOM

SIMULATION RESULTS For input peak voltage of 80 V, RL load

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PS

(W)

QS

(Var)

PR

(W)

QR

(Var)

VLOAD

(V)

14.12 95.68 7.705 77.05

60

13.47 83.77 8.773 70.19

65

13.15 69.23 10.08 60.45

70

13.1 51.28 11.68 46.73

75

Table 1: Results of Simulink model without STATCOM

SIMULATION – WITH STATCOM

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Figure 5: Simulink model with STATCOM

SIMULATION RESULTS

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PS

(W)

QS

(Var)

PR

(W)

QR

(Var)

VLOAD

(V)

15.14 78.02 8.7 87.01 80

14.34 68.57 9.657 77.26 80

13.8 58.33 10.73 64.38 80

13.62 47.53 11.91 47.66 80

For input peak voltage of 80 V, RL load with STATCOMTable 2: Results of Simulink model with STATCOM

ADVANTAGES OF STATCOM• Smooth Voltage control over a wide range of operating conditions • Improves transmission reliability and power quality to a great extent • Fast response than many other FACTS devices• Useful for a variety of power quality issues• Feasible and Economic to implement

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REFERENCES1. N. G. Hingorani, L. Gyugyi, Understanding FACTS

Concepts and technology of Flexible AC Transmission Systems, New York, 1999, pp: 1-20, 179-195.

2. V.S. Tejwani, H.B. Kapadia, A.S. Pandya, J.B. Bhati, Power Quality Improvement in Power Distribution System using D-STATCOM, IEEE Engg (NUiCONE), pp: 1-6, Nov. 2013.

3. R.Abidi, M.Nour, Analysis of a D-STATCOM in a 25kV Power Distribution Systems using Simulink, International Journal of Electrical and Electronics research, Vol. 2, Issue 2, pp: (26-34), Month: April - June 2014.

4. A. E. Xavier, STATCOM and its Simulink Model, [Online]. Available: http://shodhganga.inflibnet.ac.in/bitstream/10603/22975/7/07_chapter%202.pdf

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REFERENCES ctd.,5. J. George, “ Reactive Power Compensation

using Multilevel Inverter based STATCOM”, India, July 2011.

6. N. Rana, S. Agarwal, Reactive Power Compensation using STATCOM, International Journal of Computer Applications, Kurukshetra,

7. G.E. Valderrama, “Reactive power and imbalance compensation using STATCOM with dissipativity-based control”, IEEE Trans. Control System Technology, vol:9, Issue:5, pp: 718 - 727

8. M. G. G Titus, “ Reactive Power Compensation using STATCOM for single phase distribution system”, Circuit, Power and Computing Technologies, pp: 1-5.

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THANK YOU

PRESENTED BY NEHA L. JAIN CB.EN.U4EEE13034

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