ETAP - ocp - Optimal Capacitor Placement

1. © 1996-2009 Operation Technology, Inc. – Workshop Notes: Optimal Capacitor Placement
Optimal Capacitor
Placement

2. Slide 2© 1996-2009 Operation Technology, Inc. – Workshop Notes: Optimal Capacitor Placement
Problem of Var Flow in
Power Systems
• Loads and delivery apparatus (e.g., lines
and transformers) are inductive in nature
• Most power systems operate at a lagging
power factor
• Resulting system capacity reduced, system
loss increased and system voltage
decreased

3. Slide 3© 1996-2009 Operation Technology, Inc. – Workshop Notes: Optimal Capacitor Placement
Purposes of Shunt
Capacitor Applications
• Var support – Primary benefit for
transmission systems and secondary benefit
for distribution systems
• Voltage control – Primary benefit for both
transmission and distribution systems
• System capacity increase – Secondary
benefit for transmission systems and primary
benefit for distribution systems

4. Slide 4© 1996-2009 Operation Technology, Inc. – Workshop Notes: Optimal Capacitor Placement
Purposes of Shunt
Capacitor Applications
• System power loss reduction – Secondary
benefit for transmission systems and primary
benefit for distribution systems
• Billing charge reduction – Not applied to
transmission systems but a primary benefit
for distribution systems

5. Slide 5© 1996-2009 Operation Technology, Inc. – Workshop Notes: Optimal Capacitor Placement
General Process for Placing
Shunt Capacitors
• Determine bank size in kvar
• Determine connection location
• Determine a control method
• Determine a connection type (wye or delta)

6. Slide 6© 1996-2009 Operation Technology, Inc. – Workshop Notes: Optimal Capacitor Placement
General Methods for
Capacitor Placement
• Rules of Thumb
• Power Flow
Based
• Optimal

7. Slide 7© 1996-2009 Operation Technology, Inc. – Workshop Notes: Optimal Capacitor Placement
Optimal Capacitor
Placement in ETAP
• Genetic Algorithm - Use Genetic method to
find optimal (sub optimal) solution
• Expert System Initialization- Use power
system knowledge to find a good initial
solution

8. Slide 8© 1996-2009 Operation Technology, Inc. – Workshop Notes: Optimal Capacitor Placement
Genetic Algorithm
• An optimization technique based on the
theory of nature selection
• An iterative procedure that maintains a
constant-size population of candidate
solutions
• Coding, initialization, fitness evaluation,
selection, crossover, mutation

9. Slide 9© 1996-2009 Operation Technology, Inc. – Workshop Notes: Optimal Capacitor Placement
ETAP OCP Capabilities
• Find capacitor’s best location and bank size
• Minimize the total cost of installation and operation
• Handle radial or meshed balanced networks (PS
5.0)
• User selectable capacitor placement purpose
• Global or individual constraints

10. Slide 10© 1996-2009 Operation Technology, Inc. – Workshop Notes: Optimal Capacitor Placement
ETAP OCP Capabilities
• Analysis capacitor control method and
review capacitor impact on the system with
load duration setting
• Speed and precision ratio control by users
• Determine available capacitor installation
locations by users

11. Slide 11© 1996-2009 Operation Technology, Inc. – Workshop Notes: Optimal Capacitor Placement
ETAP OCP Capabilities
• Determine maximum capacitor size using
maximum load and determine switchblade
capacitor size using minimum load
• Use average or source energy cost
• Focus on saving during the whole planning
period

12. Slide 12© 1996-2009 Operation Technology, Inc. – Workshop Notes: Optimal Capacitor Placement
Display Results
• LF results for maximum loads
• New capacitor locations and sizes

13. Slide 13© 1996-2009 Operation Technology, Inc. – Workshop Notes: Optimal Capacitor Placement
Plot Results
• Loss reduction savings during the planning
period
• Capacitor operation cost during the planning
period
• Profit during the planning period

14. Slide 14© 1996-2009 Operation Technology, Inc. – Workshop Notes: Optimal Capacitor Placement
Report Results
• Load Flow related reports
• Capacitor locations and sizes
• Load flow results for maximum, average and
minimum loads
• Branch capacity release

15. Slide 15© 1996-2009 Operation Technology, Inc. – Workshop Notes: Optimal Capacitor Placement
Example
• Run NR Load Flow and look at bus voltages
(critical under voltage is set to 95% and
marginal under voltage is set to 98%)
• Switch to OCP mode and look at the study
case settings
• Run OCP and look at the voltage
improvements