Load Flow Example 1 1. Build the the following following system system
Element Parameters Type MOV Lump Load
Static Load Capacitor Syn Motor
Element MOV3, MOV5 Lump2 Lump4 & Lump 6 Load1, Load6, Load8 Load3, Load5 CAP1 Syn1 Syn2, Syn4
ETAP Workshop Notes
Parameters Initial Status = Throttle PF=85%, Constant kVA Load = 50%, Rated kV = 13.8 PF=85%, Constant kVA Load = 80%, Rated kV = 0.46 kV = Bus Nominal kV, PF=80% kV = Bus Nominal kV, PF=100% kV=4.16, kvar/Bank = 150 kvar, # of Banks = 2 PF @ 100% Load = 80%, FLA = 403.5 PF@100% Load =91.71%, FLA = 220.1
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Load Flow Example 1
ETAP Workshop Notes
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Load Flow Example 1
2. Run Load Flow. Results are displayed below.
ETAP Workshop Notes
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Load Flow Example 1
ETAP Workshop Notes
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Load Flow Example 1 I. Exercise 1 – Create Configurations 1. Create new configurations and study cases New Configurations Name Configuration Normal Open Tie-Breaker CB3 and CB4 and close all other CBs. Load Shift Close tie- breaker CB3 & CB4 and open both side CBs of T5 and Cable5 T3 Down Based on Normal configuration, close CB3 and open both side CBs of T3. T4 Down Based on Normal configuration, close CB4 and open both side CBs of T4. TieCBClosed Both Tie- Breaker CB3 and CB4 are Closed.
Name DesignLoad
90%Load
New Study Cases Configuration Use Design load without diversity factor. Use Design for generation category. Use default values for Adjustment Page. Loading and generator overexcited alert: Critical = 100%, Marginal = 95%. Use global diversity factor to set all load to 90 Use the default setting for Adjustment. All Loading and generator overexcited alert: Critical = 100%, Marginal = 95%.
II. Exercise 2 – Check System Voltage Condition 1. Check System Voltage Condition Run different cases to see if there is voltage problem. If there is any problem, fix it.
III. Exercise 3 – Use LF Calculation to Check Equipment Rating 1. Check Cable 2 Rating (Use Revision) Run different cases to see if Cable2 is over/under sized. Consider different operating conditions. Use derated ampacity based on default Tray setup (ICEA P54-440, H=6, W=18, Fill=30%, No cover, cumulative effect and fire protection). 2. Check Cable 5 & Cable 7 Rating (Use Revision) Run different cases to see if Cables 5 & 7 is under over/under sized. Consider all possible configurations. Use derated ampacity based on default Tray setup (ICEA P54-440, H=6, W=18, Fill=30%, No cover, cumulative effect and fire protection). 3. Check XFMR T4 and T5 Rating For all cases under consideration, are T4 and T5 under/over sized. What size would be more adequate? Check system voltage condition again.
ETAP Workshop Notes
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Load Flow Example 1 4. Determine Rating For Bus8, Bus12, CB8 and CB9 Operating conditions to be considered: configuration, loading, compatibility with upper stream elements. Consider the condition when one transformer (T4 or T5) is down.
III. Exercise 4 – Maximize Generator Output 1. Fully utilize co-gen capability Let generator output 10 MW. Check if there is any problem with system voltage, utility operating PF, etc.
III. Exercise 5 – Voltage Regulation 1. Operating without co-gen See if high voltage buses can maintain V >= 98%. Use transformer tap to correct voltage problem. Does it cause over voltage condition when generator is in? Try LTC or use LTC tool to determine tap position.
IV. Exercise 6 – Element Sizing 1. Size Cable 2 (Use Revision) 2 by 2 conduit Ta=25, Tc=90, Rho = 95 2. Size Cable 5 & 7 (Use Revision) A/G Tray with Height = 6, Width = 20, Fill = 25% Tray Ta = 30, Tc=90 Use ICEA method. 3. Size equipment cable for Mtr4 Set up Ampacity page data: Ta=35, Tc=90, NEC, A/G Tray with top cover. Size requirements: Vd (2%), Vst(80%), Ampacity (Mtr4 with MF), and SC (26kA, 0.06 second). Use library: ICEA, Rubber, Magnetic installation, 100% insulation level, 0.6kV, 3/C, CU conductor, 200ft.
ETAP Workshop Notes
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Load Flow Example 2
1. Open the ETAP project LFExample-2 2. Run Load Flow
3. You will notice a large number of under voltage conditions throughout the system 4. Correct these under voltage conditions in the system 5. For a solution to this problem please select the following Revision = Solution Configuration = Solution-CFG
Or run Load Flow Example-2 Scenario
ETAP Workshop Notes
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