Load Mix

1
Load Mix Load Location How do these selections
affect your WindMil model and why?
Keith MullenR.W. Beck
2
Load Mix and Load Location

• Classification of Power System Loads
• Load Mix Modeling
• Load Location Modeling
• Test Model
• Load Mix Case Study
• Load Location Case Study

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Load Mix and Load Location

• Classifications of Power System Loads
• Constant Power (SPQ)
• Constant Impedance (Z)
• Constant Current (I)
• IEEE Std 399-1980 Recommended Practice for
  Industrial Commercial Power System Analysis
  (Brown Book)

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Load Mix and Load Location

• Classifications of Power System Loads
• IEEE Std 399-1980 Recommended Practice for
  Industrial Commercial Power System Analysis
  (Brown Book)

(
)
(
)
k

k 0 Constant SPQk 1 Constant Ik 2
Constant Z
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Load Mix and Load Location

• Classifications of Power System Loads
• IEEE Brown Book
• Determining the appropriate load mix is very
  difficult when studying utility type systems,
  because the nature of the load is not known
  accurately.
• H. Lee Willis Spatial Electric Load Forecasting
• Load mix is estimated based on a spatial end-use
  appliance model, and can be expensive to obtain.

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Load Mix and Load Location

• Classifications of Power System Loads
• State of Washington load research

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Load Mix and Load Location

• Classifications of Power System Loads
• Spatial Electric Load Forecasting H. Lee
  Willis Allocation of peak demand for a
  southeastern US utility

8
Load Mix and Load Location

• Classifications of Power System Loads
• Spatial Electric Load Forecasting H. Lee
  Willis

9
Load Mix and Load Location

• Load Mix Modeling
• Detailed or Non-Detailed Models
• Load Mix Options
• Constant kVA (Milsoft Default)
• Constant Impedance
• Constant Current
• Combination
• Load Allocation Preferred

10
Load Mix and Load Location

• Load Location Modeling
• Non-Detailed Models
• Load Location Options
• Source
• Uniform (Milsoft Default)
• Load
• Load Allocation Preferred

11
Load Mix and Load Location

• Load Location Modeling
• Uniform (Milsoft Default)

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Load Mix and Load Location

• Load Location Modeling
• Uniform (Milsoft Default)

OPEN
B
A
X
Allocated Load
OPEN
B
A
X
Allocated Load
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Load Mix and Load Location

• Load Location Modeling
• Source or Load

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Load Mix and Load Location

• Load Location Modeling
• Source or Load

OPEN
B
A
X
L
S
OPEN
B
A
X
S
L
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Load Mix and Load Location

• WindMil Settings

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Load Mix and Load Location

• WindMil Settings

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Load Mix and Load Location

• WindMil Settings

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Load Mix and Load Location

• WindMil Settings

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Load Mix and Load Location

• Test Model
• Customer Level Detail
• Rural System
• 22 Substations (25 kV 12 kV)
• Summer Peaking 109 MW
• 29,145 Consumer Elements
• 12.5 Consumers/mi.
• Avg. Section Length 370 ft.
• Fully Implemented AMR

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Load Mix and Load Location

• Test Model

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Load Mix and Load Location

• Load Mix Case Study
• Case 1 Milsoft Default
• Case 2 Adjust Mix to
• Residential 30/70 (SPQ/Z)
• Sm Commercial 50/50 (SPQ/Z)
• Lg Commercial 60/40 (SPQ/Z)
• Performed Load Allocation

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Load Mix and Load Location

• Load Mix Case 1 Milsoft Default

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Load Mix and Load Location

• Load Mix Case 2 Adjusted Mix

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Load Mix and Load Location

• Load Mix Results Allocated Load

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Load Mix and Load Location

• Load Mix Results Performance

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Load Mix and Load Location

• Load Mix Summary
• Load mix information is customer-specific and may
  be difficult to obtain
• Load mix default is conservative
• Load mix selections can be used to make
  adjustments to model results
• Accuracy must be verified in the field

27
Load Mix and Load Location

• Load Location Case Study
• Case 1 Milsoft Default
• Case 2 Source
• Case 3 Load
• Performed Load Allocation

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Load Mix and Load Location

• Load Location Results Performance

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Load Mix and Load Location

• Load Location Summary
• Applies to only non-detailed models
• Load location default is not affected by the
  direction of power flow
• Load location selections can be used to make
  adjustments to model results
• Accuracy must be verified in the field