2009-10-01 Energy Management Systems I

2009-10-01 Energy Management Systems I - Energy Management...

Info iconThis preview shows pages 1–8. Sign up to view the full content.

View Full Document Right Arrow Icon
Energy Management Systems I Jovan Ilić ECE 18-418 Fall 2009
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
What is EMS and why do we need it? • Customers want reliable, high quality power delivery • There is a large number of generators and loads • Reliability and quality is achieved through sharing generated power • Generation must be distributed among producers to balance out the total demand satisfying technical requirements
Background image of page 2
Issues of Interest • Power Flow (PF) computations • Optimal Power Flow (OPF) computations • Controlled switching • Contingency analysis • Short circuit computations • Stability analysis
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
AC Z AC Z Z V1 V2 L Z12 Z13 Z23 So, what is different from a usual electrical circuit calculations? Power Flow Computations Solve a power system network for bus voltage magnitudes and angles
Background image of page 4
Differences Between Electrical Circuits and Power Networks • Power demands expressed as P/Q, not RLC • Power sources expressed as P/V, not V • Frequency drift and system instability is possible due to P/Q generation demand mismatch • Network equations are non-linear • Multiple solutions some of which are possible and some are not
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Network equations are not non-linear because AC nature of the system!       2 3 1 -0.131296-0.0213811 i,-0.131296+0.0213811 i,0.728969,1.03362 0.221336-0.284416 i,0.221336+0.284416 i,0.183579,0.873749 19.0996+3.05797 i,19.0996-3.05797 i,10.8745,0.926289 G V V P AC Z AC Z Z V1 V2 L Z12 Z13 Z23 12 13 23 2 3 1 0.1 2 2.5 1.0 G D Z Z Z PW VV
Background image of page 6
Mathematical tools for solving a system of nonlinear equations. Gauss-Seidel iterative algorithm 1. Easy to program 2. Slow to converge 3. Might have to use “fudging” constants to control convergence 4. Point of convergence depends on the initial guess Newton-Raphson iterative algorithm 1. Harder to program 2. Very fast (quadratic) convergence 3. “Fudging” constants might be necessary 4. Point of convergence depends on the initial guess 5. Requires calculating the Jacobian
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 8
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 18

2009-10-01 Energy Management Systems I - Energy Management...

This preview shows document pages 1 - 8. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online