Transcript Document
A Symmetrical Hybrid Power Flow Controller Jovan Bebic, P.Eng. October 31/2003 © Copyright by J. Bebic 2003 Overview VSC Basics Converter Based FACTS Devices Proposed Topology Steady-State Operation Reachable Sets and P- Curves H P F C Slide 2 of 15 Dynamic Control Summary Future Work VSC Basics H P F C Slide 3 of 15 P P Q Converter Based FACTS Compensators H P F C Slide 4 of 15 VS X S IS V1V1 VM V2 P P 0QE Q P 0 PQ P V2 XR VR IR QB STATCOM UPFC SSSC Proposed Topology H P F C Slide 5 of 15 VS XS V1 V2 VM IS XR VR IR QM HPFC Limits and Constraints VDC PX H P F C Slide 6 of 15 VS X S V1 IS PS P1 VX C DC VM PY VY V2 XR VR IR IM P2 PR BM HPFC VX VX max VY VY max V1 V1max VM VM max PX PY P1 P2 PS PR PX PY IS IX max IR I Y max V2 V2max Equal Power Lines VS H P F C Slide 7 of 15 PS const IM V1 IS V IS1PRVMconst X IPS2 const IM IS IR S VY IR V2 V1X VVSI1 jX VMS IS M VMPS V S IS VR VY2 V VjB V jXMR IR R2 M Steady-State Operation H P F C Slide 8 of 15 IM IM IR IS IM IS IR VM V1S ISV1 VX V2 VV XY VS VM VM VR YX V1 VV V IR 2 VY V2R V Reachable Sets Line Parameters Equipment Limits & XS , X R VX max , I X max ; VY max , I Y max H P F C Line Conditions VS , VR , IS , IR Slide 9 of 15 P1 , Q1 , Q2 P- Curves H P F C Slide 10 of 15 System Properties H P F C Slide 11 of 15 A system of variable structure, with infinitely many internal operating points, for every line operating point. A nonlinear control problem Dynamic Control Operator specifies P1 , Q1 , Q2 H P F C table lookup P1 , Q1 , Q2 ISref , IRref use VX , VY to control IS , IR Slide 12 of 15 Controlling the Power Balance of Converters H P F C I MPX * DC v VSvDC iDC X S vSed vSeqI PS VX V1 S x P1 * iDC y x y 2 2 VS VDC C DC VM IM PY iSref ISxy xy VY V2 X VR IS VM R IR IR BM HPFC Slide 13 of 15 P2 VR PR Summary HPFC UPFC H P F C Slide 14 of 15 Power flow control Improves first swing stability margin Topological symmetry Able to utilize existing shunt compensation Future Work H P F C Slide 15 of 15 Study machine based equivalents. Study dual topology. Formulate “optimality” algorithms based on “reachable sets” algorithms. Optimize the controller. Apply the concept of “equal power lines” in load flow programs.