CEPEL - Centro de Pesquisas de Energia Elétrica

Transcription

1 VII SEPOPE May - 21st to 26th CURITIBA (PR) - BRASIL A Small-Signal Signal Stability Program Incorporating Advanced Graphical User Interface Nelson Martins Paulo E.M. Quintão Herminio J.C.P. Pinto Alex de Castro Sergio Gomes Jr. Julio C.R. Ferraz CEPEL - Centro de Pesquisas de Energia Elétrica

2 PacDyn - Small-Signal Signal Stability Analysis and Control Determine nature and cause of small-signal signal stability problems. Most effective locations for placing stabilizers or FACTS devices to damp system oscillations. Controller design (AVR, PSS, Governor, HVDC link and FACTS devices). Coordinated design of multiple controllers. Reduced-order models (SISO & MIMO). Others.

3 PacDyn Functions Poles Zeros Time Response Frequency Response Reduced Order Model (SISO & MIMO) Augmented Jacobian Matriz Modes-Shape, Residues, Controllability Factors, Observability Factors, Participation Factors Root-Locus & Root-Contour Plots Pole Alocation Machine Tests MATLAB Output

4 PacDyn DOS Graphical User Interface Plotting Programs Frequency Response Time Response Network Data (Graphical FORTRAN) Eigenvalues and Zeros Mode- Shapes Residues PacDyn (FORTRAN) Dynamic Data Output File

5 PacDyn for Windows Graphical User Interface PacDyn ODBC Graphical User Interface Database (Visual C++) Frequency Response Time Response Network Data Eigenvalues & Zeros Mode- Shapes Residues PacDyn (FORTRAN) Dynamic C Data Printout File

6

7 Large Power System Applications Brazilian North-South Interconnection 2,380 buses, 3,450 circuits, 120 generators Jacobian Matrix order: 13,000 (1,700 State variables) Argentinean Interconnected System (SADI) 1,200 buses, 1,600 circuits, 170 generators Jacobian Matrix order: 9,000 (2,000 State variables) Nordic Interconnection (Nordel( Nordel) 3,000 buses, 4,000 circuits, 1,000 generators Jacobian Matrix order: 55,000 (11,000 State variables) UCPTE-CENTREL CENTREL Interconnection 2,000 buses, 3,200 circuits, 380 generators Jacobian Matrix order: 11,000 (2,200 State variables)

8 Brazilian North-South Interconnection 0.93 Step Response - Scenario R 0.66 Paulo Afonso 4 Xingo Luiz Gonzaga Time (s) Step responses of major system generators for Scenario R (λ = ± j 1.079) (with existing PSSs and without TCSC stabilizer)

9 Brazilian North-South Interconnection 1.00 Reduced Order Model 6th Order Model Full System Time Response Time (s) Active power flow in the North-South tie-line. Responses of the full model and the 6 th order reduced model

10 Brazilian North-South Interconnection Mode-Shape Output: WW Eigen: j *** COMPLEXO PAF + UAS *** *** AREA LESTE *** *** AREA SUL *** Itaipu 50 Hz *** SUDOESTE DA BAHIA *** *** AREA OESTE *** South-Southeast North-Northeast *** AREA TUCURUI-BELEM *** *** AREA MARANHAO *** ************* ITAIPU ************* ************* COPEL ************** Mode-shape for North-South inter-area mode (λ = ± j 1.079)

11 Brazilian North-South Interconnection Transfer Function Residues Input: VREF Output: WW Eigen: j Xingo Paulo Afonso 4 Itaipu Diagram of transfer function residues, used to determine the most effective generators for installing or retuning existing stabilizers (λ = ± j 1.079)

12 Brazilian North-South Interconnection 2.10 Imag % 10 % 5 % 1.40 Proposed PSSs Kpss = Kpss = 25 Existing PSSs Existing PSSs Gains Real 0.30 Locus of North-South mode following changes in the PSS gains at Xingó, Paulo Afonso IV and Itaparica power plants

13 Brazilian North-South Interconnection 12. Root-Contour Plot 15% 10% 5% Northeastern Modes South-Southeast Mode North-Northeast Mode Real North-South Mode Root-contour plot as the gains of the PSSs at Xingó, Paulo Afonso IV and Itaparica are raised from zero to 25 pu/pu

14 Argentinean Interconnected System (SADI) Inter-Area Modes for 16 Base Cases 15% 10% 5% Mode 1 Mode 2 Mode Real Inter-area modes for 16 base cases

15 Argentinean Interconnected System (SADI) Inter-Area Modes for 62 N-1 Contingencies 15% 10% 5% Mode 1 Mode 2 Mode Real Inter-area modes for 62 N-1 contingencies

16 Nordic Interconnection 10% 5% 5 4 Imag. part Finland mode Sweden mode North mode West mode Real part Root contour for SVC stabilizer design. Contingency case, 2,050 MW export

17 Future Developments All results stored in a single database. Full integration with power flow and transient stability programs. Advanced methods for coordinated control design. Non-linear search for stability boundaries in the control parameters or loading spaces. More extensive use of macro functions. Modeling of UPFC devices, etc.

18 Final Comments Small signal stability programs are now used worldwide in the analysis and damping control of inter-area oscillations. Engineering study productivity is much enhanced with the use of an advanced GUI. Advanced eigensolution methods are vital in this area.