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THỰC HIỆN TÍNH TOÁN MÔ PHỎNG TRÊN PHẦN MỀM PSSE VỚI HỆ THỐNG ĐIỆN 24 NÚT CỦA IEEE. NỘI DUNG CHÍNH PHẦN 3 (Calculation for IEEE 24 Bus System): 1. Overview of the IEEE 24 Bus System. 2. Load Flow Analysis. 3. N-1 Contingency Analysis. 4. Short-Circuit Analysis. 5. PV-QV Analysis. 6. Dynamic Analysis of 3ph and SLG Faults.
TRANSMISSION & TRANSMISSION & DISTRIBUTION A Division of Global Power POWER SYSTEM STABILITY CALCULATION TRAINING Day 1 - Review of the Main Topics Covered in Course A December 6, 2013Prepared by: Frida Ceja-Gomez eBook for You OUTLINE • Overview of the IEEE 24 Bus System • Load Flow Analysis • N - 1 Contingency Analysis 2 • N - 1 Contingency Analysis • Short-Circuit Analysis • PV & QV Analysis • Dynamic Analysis of 3-ph and SLG Faults eBook for You 3 IEEE 24 BUS SYSTEM REVIEW System Components & Load Flow Simulation eBook for You The IEEE 1996 Reliability Test System 4 SYSTEM COMPONENTS • Two areas (230kV & 138kV) • 21 branches • 10 generators (implicit • 10 generators (implicit GSU transformers) • 20 loads • 5 two-winding transformers with OLTC • 3 fixed shunts eBook for You Running the load flow simulation 5 • Open the saved case file and the single line diagram • Run a power flow simulation; no errors should be encountered LOAD FLOW ANALYSIS encountered • Identify the main direction of the power flow on the SLD • Use the Limit Checking Reports to identify overloads or voltage issues eBook for You N-0 Criteria 6 • How did we resolve the issues encountered in Course A? • Transformer overloads LOAD FLOW ANALYSIS overloads • Low voltages • Swing machine’s reactive power limit exceeded eBook for You Eliminating the overloads 7 • All the transforms originally had a rating of 100MVA • It was necessary to modify the transformers’ ratings as shown below LOAD FLOW ANALYSIS • Note that the resistance/reactance values do not need to be modified since these parameters were input with respect to the winding MVA base, which was left unchanged eBook for You Correcting the voltage issues 8 • To address the low voltage at buses 3 and 24, we added a fixed shunt capacitor of 75 MVAR at bus 3 LOAD FLOW ANALYSIS • To address the low voltage at buses 4, 5, 6, 8, 9, 10, 11 and 14, we placed a fixed shunt capacitor of 115 MVAR at bus 10 • Why did we placed the shunts on the low voltage side? eBook for You Swing bus reactive power 9 • How was this problem corrected? • To correct this problem, it was necessary to increase the scheduled voltage at nearby PV buses LOAD FLOW ANALYSIS increase the scheduled voltage at nearby PV buses to encourage other machines to increase their reactive power output • Specifically, we modified the scheduled voltage at bus 23 to 1.03pu eBook for You 10 IEEE 24 – N-1 CONTINGENCY ANALYSIS eBook for You [...]... eBook for You Remedial Action Schemes IEEE 24 – SHORT-CIRCUIT ANALYSIS eBook for You 22 23 SHORT-CIRCUIT ANALYSIS • When we built the IEEE 24 Test System, there was no input data for the zero sequence parameters • What assumptions can we make when the negative and zero sequence parameters are not available? eBook for You Negative and Zero Sequence Parameters 24 SHORT-CIRCUIT ANALYSIS Negative and Zero... distribution factor file • Set the initial transfer increment to 10MW • Make sure to choose the right settings • Select the source and sink subsystems eBook for You • 32 PV ANALYSIS PV Analysis Results Plot the interface flow for each contingency • What is the maximum power transfer from Area 2 to Area 1 for each case? eBook for You • 33 PV ANALYSIS PV Analysis Results In Course A, we had plotted the voltage... is the point of voltage collapse for each case? • Which one seems to be the worst contingency? eBook for You • 34 PV ANALYSIS PV Analysis Results Now do the same for Bus 24 • What is the point of voltage collapse for each case? • Which one seems to be the worst contingency? eBook for You • 35 QV ANALYSIS QV Analysis Applications What can we do with QV analysis results? • Identify the stability limit... linear power flow • Choose to analyze three-phase and lineto-ground faults • Select the output as Fault current summary table • Select all buses and click Go eBook for You • 27 SHORT-CIRCUIT ANALYSIS • The shortcircuit analysis report should appear in the output bar • Which buses have a large fault current? Why? eBook for You Automatic Sequencing Fault Calculation in PSS®E IEEE 24 – VOLTAGE STABILITY... the power transfer from Area 2 to Area 1 eBook for You PV Analysis 30 PV ANALYSIS PV Distribution Factor File Input Use the subsystem file created for N-1 contingency analysis • The top image shows the monitoring file we created • We also prepared a contingency file to study the loss of each one of the transformers eBook for You • 31 PV ANALYSIS PV Analysis Go the PV Analysis window and create the... Preparing the input files for the DFAX file Also, a monitoring file was created for • overloads on all branches • the buses for each subsystem having a voltage below 0.9pu or above 1.1pu eBook for You • 13 N-1 CONTINGENCY ANALYSIS Preparing the input files for the DFAX file Finally, we wrote contingency file to trip each of the branches in the system, one at a time eBook for You • 14 N-1 CONTINGENCY ANALYSIS... Identify the stability limit (bottom of QV curve) • Determine the minimum reactive power for stable operation • Identify the type and size of compensation required for voltage stability eBook for You • 36 QV ANALYSIS • Recall that QV analysis is not part of the dynamic analysis, so use the nonconverted saved case file • Select the bus you wish to study • Use the same distribution factor file used in