Coordinated tuning of PSS and TCSC to improve Hopf Bifurcation margin in multimachine power system by a modified Bacteria Foraging Algorithm

Abstract Recent research works have reported the effects of rotor angle dynamics of generators on bifurcation related system instability. This study intends to verify the possible influence of the Power System Stabilizers (PSS) and the Thyristor Controlled Series Capacitors (TCSC), on instabilities related to the Hopf Bifurcation (HB). Recently proposed optimization algorithm known as Bacteria Foraging Algorithm (BFA) in its modified version is applied in this study to tune the controller parameters of nine numbers of PSS and two numbers of TCSC present in the 10 machine New England power system. The main objective of this work is to maximize the margin of loading in the same system before the occurrence of the HB. Moreover, the formulation of a properly designed objective function is also an important issue that affects the final result. The objective function, that is formulated only to improve the overall damping in power system, may not be sufficient to avoid the HB under stressed operating condition. Therefore, this study proposes to reformulate an eigenvalue based objective function to improve the extent of loading before the HB could occur in the system. A coordinated control of the TCSC with those of the PSS may enable the controllers to delay the point of HB, compared to the case when the PSS alone were operating in the system. At the outset, the control parameter settings of several transformer taps and PV-bus voltages of nine generators were optimized to improve the steady state Voltage Stability Limit (VSL) of the system. At these settings, the damping controller parameters are tuned to improve the loadability before the point of HB. Similar approach is adopted when the TCSCs were operating coordinately with the PSS. At the end, small perturbation cases were simulated in the system to verify the performance of designed controllers in time domain analysis. The results further establish the efficacy of the controllers

[1]  Leon Y. Bahar,et al.  Static bifurcations in electric power networks: Loss of steady-state stability and voltage collapse , 1986 .

[2]  Felix F. Wu,et al.  Chaos in a simple power system , 1993 .

[3]  Nadarajah Mithulananthan,et al.  Comparison of PSS, SVC, and STATCOM controllers for damping power system oscillations , 2003 .

[4]  Fernando L. Alvarado,et al.  Sensitivity of the loading margin to voltage collapse with respect to arbitrary parameters , 1997 .

[5]  Harry G. Kwatny,et al.  Power System Dynamics and Control , 2016 .

[6]  Venkataramana Ajjarapu,et al.  The continuation power flow: a tool for steady state voltage stability analysis , 1991 .

[7]  Peter W. Sauer,et al.  Dynamic aspects of voltage/power characteristics (multimachine power systems) , 1992 .

[8]  I. Erlich,et al.  Simultaneous coordinated tuning of PSS and FACTS damping controllers in large power systems , 2005, IEEE Transactions on Power Systems.

[9]  Costas Vournas,et al.  Voltage stability analysis in transient and mid-term time scales , 1996 .

[10]  E. S. Ali,et al.  Bacteria foraging optimization algorithm based load frequency controller for interconnected power system , 2011 .

[11]  Mehrdad Ghandhari,et al.  Improving power system dynamics by series-connected FACTS devices , 1997 .

[12]  K. R. Padiyar,et al.  Analysis of small signal voltage stability in multimachine systems using detailed and reduced formulations , 2005 .

[13]  K. R. Padiyar,et al.  Dynamic analysis of small signal voltage instability decoupled from angle instability , 1996 .

[14]  S. K. Tso,et al.  Design optimisation of power system stabilisers based on modal and eigenvalue-sensitivity analyses , 1988 .

[15]  P. Kundur,et al.  Power system stability and control , 1994 .

[16]  Pouyan Pourbeik,et al.  Interactions between, and effectiveness of power system stabilizers and FACTS device stabilizers in multimachine systems , 2000 .

[17]  A.A.P. Lerm,et al.  Avoiding Hopf bifurcations in power systems via set-points tuning , 2004, IEEE Transactions on Power Systems.

[18]  Graham Rogers,et al.  Power System Oscillations , 1999 .

[19]  J. Nanda,et al.  Multi-machine power system stabilizer design by rule based bacteria foraging , 2007 .

[20]  Narayana Prasad Padhy,et al.  Power-system Stability Improvement by PSO Optimized SSSC-based Damping Controller , 2008 .

[21]  Kevin M. Passino,et al.  Biomimicry of bacterial foraging for distributed optimization and control , 2002 .

[22]  S. Mishra.  Bacteria foraging based solution to optimize both real power loss and voltage stability limit , 2007, 2007 IEEE Power Engineering Society General Meeting.