Research Journal of Applied Sciences, Engineering and Technology 1(2): 40-43, 2009
ISSN: 2040-7467
© M axwell Scientific Organization, 2009
Submit Date: June 05, 2009
Accepted Date: July 15, 2009
Published Date: August 31, 2009
Implementation of FC-TCR Using Low Cost 89c 2051 Controller
1
1
T. V ijayakum ar, 2 A. Nirmalkumar and 3 N.S. Sakthivelmurugan
EEE, Karpagam College of Engineering, Coimbatore-641032, India
2
EEE, Bannari Amm an Institute of Techno logy , Sathy, India
3
EEE, Royal Co llege o f Engineering, Thrissur, In dia
Abstract: This paper deals with the simulation and implementation of fixed capacitor thyristor controlled
reactor system . The TCR sy stem is simulated using MATLA B and the simulation results are presented. The
power and control circuits are simulated. Laboratory model for the FCR – TCR system is implemented using
89C2051 and it is tested. The current drawn by the TCR varies with the variation in the firing angle. The
experimental resu lts are compa red w ith the sim ulation results.
Keyw ords: Facts, TCR, M ATLA B, FC, Simulink, Reactive Power
com mon ly used and studied under sinusoidal voltage
conditions, waveforms corresponding to the controlled
curren t presen t high harmo nic content.
This paper focuses on the thyristor-controlled reactor
(Karady, 1993) as shown in Fig 1a. Compensation with
TCR consists of controlling the current in the reactor L
from a maximum (thyristor valve closed) to zero (thyristor
INTRODUCTION
In the control of Electric Power Systems, systems and
procedures are used to comp ensate dyn amically the
detrimental effects of non-linear loads. The compensation
process shou ld be carried out without important alteration
of source signal quality. Some benefits are expected using
com pensation reduction of losses in distribution lines,
harmonic content minoration, and power factor
impro vem ent. The dynamic behavior of industrial loads
requires the use of compe nsator that can be adapted to
load changes. Unfortunately, the techniques frequently
used for compensation are based on circuit controllers that
alter the wav eform of the signal subjected to control. Such
is the case of the static compensator (Miller, 1982; Lee
et al., 1992), which must perform harmonic cancellation,
reactive power compensation, power factor correction,
and energy saving. Although the static compensator is
Fig 1a: Circuit of TCR
Fig.1b.FC- TCR circuit model
Corresponding Author: T.Vijayakumar, EEE, Karpagam College of Engineering, India
40
Res. J. Appl. Sci. Eng. Technol., 1(2): 40-43, 2009
valve open) by the method of firing delay angle control.
The fixed capacitor (FC) and TCR constitute a basic VARgenerator arrangem ent (FC-T CR ). The constant capacitive
VAR generation of C is opposed by the variable VAR
absorption of the TCR. The circuit model of FC TCR
system is show n in Fig 1b. TCR is added in parallel w ith
the fixed capac itor to get smooth variation of reactive
pow er.
Calculation of the firing angle can be made in the time
dom ain (Gomez , et al, 1992) or in the frequ ency dom ain
(Montafeo, et al, 1993; Montafeo,et al 1994), using
different approaches. Assuming the supply voltage to be
sinusoidal, calculation of the firing angle is obtained w ith
minimum complexity (M iller , 1982 ;Guitierrez, et al
,1993). However, the increase in " = B / 2 to " = B,
produces increasing distortion of the current in the TCR
branch, and con sequen tly that of line current. It increases
the rms value of the line current and the THD, and
deteriorates the pow er factor. Optimal location of multitype
Facts devices in a power system by means of genetic
algorithm is given by ( Stephane Gerbex , et al, 2001).
Fig 2a: TCR Current Waveform with Alpha = 162 Degree
MATERIALS AND METHODS
Three bus FC-TCR system can be solved using gauss
seidal or Newton Raphson method But they gives the ready
made solution of the network.
FC-TCR system can be controlled with analog firing
control. Digital control using 8085/8086 was implemented
The literature (Miller, 1982) to (Vilathgamuna, et al
2002) does not deal with the implementation of FC-TCR
using 89C2051. An attempt is made in the present work to
implement FC-TCR system using low cost embedded
controller.
Fig 2b: Real &Reactive Power with Alpha = 162 Degree
FC–TCR System: V(t) is the input AC so urce, Z L
indicates the line impeda nce.TC R is realized using L and
antiparallel switch T. Load is represented as a series
comb ination of R C and L L.
The mathem atical expression are as follows
Fig 3a: TCR Current Waveform with Alpha = 144 Degree
I o Rms = V S / R ( 4(1- " / B) (Cos 2 "+1/2)+ 6 / B Sin " Cos
") 1 / 2
(1)
P o = Io 2 R
(2)
PF = Po ave / V S I S
(3)
RESULTS
Simulation Resu lts: The simulation was done using
Matlab Simulink version 7.2 an d the results are presented
here. Current w aveform for single phase TC R circuit is
shown in Fig 2a. Real and reactive powers with " = 162/
is show n in Fig 2b.The bidirectional switch is implemented
using 4 diodes and one thyristor. The current through
TCR with " =144/ is shown in Fig 3a.The real and
reactive pow ers with " = 144/ is show n in Fig 3b. It can
41
Fig 3b: Real &Reactive Power with Alpha = 144 Degree
be seen that the current can be varied by varying the firing
angle. The current decreases with the increase in firing
Res. J. Appl. Sci. Eng. Technol., 1(2): 40-43, 2009
angle. Thus the reactive power can be varied by varying
the firing angle.
Experimental results: Laboratory model of FC – TC R is
fabricated and tested. The firing pulses are generated using
the microcon troller 89C2051. These pulses are amplified
using the driver IC IR2110. Experimental setup of the
hardw are is shown in Fig 4a. Triggering pulses are shown
in Fig 4b.They are sync hronized w ith the zero
crossings of the supply voltage. The current waveforms
Fig 4d: Current Waveform with Alpha = 144 Degree
Fig 4a: Experimental setup of the hardware
Fig 4e: Current Waveform with Alpha = 120 Degree
Fig 4b Triggering pulses
Fig 4f : Current Waveform with Alpha = 98 Degree
CONCLUSION
Fig 4c: Current Waveform with Alpha = 162 Degree
with " = 162/ , 144/ , 128/ and 98/ are shown in figures
4c,4d ,4e and 4f respectively. Th e current decreases with
the increase in the firing angle. Thus the reactive power
can be varied by varying the firing angle.
42
The variation of reactive power using FC-TCR and
tapped inductor FC-TCR systems is analyzed. The
variation of reactive pow er with the va riation in the firing
angle is studied. The range of reactive power control can
be increased by using the combination of thyristor
controlled reactor and fixed capacitor system. The circuit
model for FC-TCR is obtained and the same is used for
simulation using Matlab Simulink. From the simulation
studies it is observ ed that reactive pow er variation is
Res. J. Appl. Sci. Eng. Technol., 1(2): 40-43, 2009
smoother by using FC TCR system. The experimental
results are alm ost similar to the sim ulation results. The
experimental results differ sligh tly due to the resistance of
the TCR.
NOTATIONS
I o Rm s
VS
R
Po
Io
P o ave
IS
"
= RM S output current
= Source Voltage
= Resistance of TCR
= Average output power
= Output RMS Current
= Average output Power
= RMS source current
= Firing angle delay
REFERENCES
Gomez A., F.Gonzalez, C.Lzquierdo C, T.Gonzalez and
F.Pozo,1992. Microprocessor based control of an
SVC for optimal load Compensation. IEEE Trans.
Power Deliv., 7(2):706-712
Gutierrez J., 1993. Compensation Components Harmonic
intensity electric system with Nonlinear Loads. Ph.D.
Thesis, Un iversity o f Seville
Karady G.G.,1992. Continuous Regulation of Capacitive
Reactive
Power.IEEE
Trans. power Deliv.,
7(3):1466-73
43
Lee S.Y., S. Bhattacharya, T. Lejonberg, A. Hammad and
S. Lefebvre., 1992. Detailed Modeling of Static VAR
Com pensators Using the Electro mag netic T ransients
Program (EMTP). IEEE Trans. Power Deliv.,
7(2):836-847
Miller T.J.E.,1987. Reactive Power Control in Electrical
System s. John W illey and Son s, New York
Montafio J.C., A. Lopez and M. Castilla,1993. Effects of
voltage Waveform
Distortion in TCR-Type
Comp ensators.
IEEE
Trans.
Ind Elect.,
40(1):373-381
Montafio J.C., J. G utie rre z, A . Lopez and M.
Castilla,1994. Effects of harmonic distortion of the
supply voltage on the optimum performan ce of a
TCR-Type Compe nsators. IEE Proc. Sci., Meas.
Technol., 141(1):15-19
Stephane G., R. Cherkaoni and A. J.Germond., 2001.
Optimal location of multitype FACTS devices in a
power system by means of Genetic Algorithm. IEEE
Trans. Power Syst., 16(3):537- 544
Vilathgamuna D.M and H.M.Nijekoon, 2002. Control and
analy sis of a new Dynam ic voltag e Re storer circuit
topology for mitigating long duration voltage
sags. Conference IEEE – IAS Annual Meeting,
2: 1105-1112