selecting extended reserve emily calvert, energy analyst 1
TRANSCRIPT
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Selecting Extended ReserveEmily Calvert, Energy Analyst
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Contents
• Overview- Scheme- System
• Inputs- Unit load- Unit configuration
• Objective function- Meet block targets- Minimise cost
• Output- Procurement schedule
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AUFLS scheme• Two blocks• Each distributor obliged
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Extended Reserve scheme• Four blocks• Spread across North Island
OverviewExtended Reserve
Block Target Min Max
1 10 8 12
2 10 8 12
3 6 5 7.5
4 6 5 7.5
Block Min
1 16
2 16
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Overview
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Extended Reserve system
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Overview
Select standard and flexible demand units for each blocktaking into account penalties and constraints
1. Meet block targets2. Minimise costs
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Objective Function
Overview
• Mixed integer linear programming• Selects demand units to meet block targets• Includes penalties and constraints• Uses iterative sampling approach• Tests against other years’ data
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Selection Tool
Input
Identifier Date 00:00 00:30 01:00 01:30 02:00 …
ABCD0001 01/04/15 10 10 10 10 10
ABCD0002 01/04/15 5 5 5 5 5
ABCD0003 01/04/15 5 5 5 5 5
ABCD0004 01/04/15 2 2 2 2 2
ABCD0005 01/04/15 1 1 1 1 1
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Unit load
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Input
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Unit load
0:00
1:00
2:00
3:00
4:00
5:00
6:00
7:00
8:00
9:00
10:00
11:00
12:00
13:00
14:00
15:00
16:00
17:00
18:00
19:00
20:00
21:00
22:00
23:00
DU1 DU2 DU3 DU4 DU5
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Input
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Unit load
0:00
1:00
2:00
3:00
4:00
5:00
6:00
7:00
8:00
9:00
10:00
11:00
12:00
13:00
14:00
15:00
16:00
17:00
18:00
19:00
20:00
21:00
22:00
23:00
DU1 DU2 DU3 DU4 DU5
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Input
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Calculate block requirements
0:00
1:00
2:00
3:00
4:00
5:00
6:00
7:00
8:00
9:00
10:00
11:00
12:00
13:00
14:00
15:00
16:00
17:00
18:00
19:00
20:00
21:00
22:00
23:00
Blocks
Input
Identifier
# current relays
# new relays
Currently allocated
Fast response Flexible …
ABCD0001 1 0 1 Y S
ABCD0002 1 0 2 N M
ABCD0003 0 0 0 N N
ABCD0004 0 0 0 N P
ABCD0005 0 0 0 N N
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Unit configuration: Capabilities
Input
IdentifierResidential
Light & Primary Industry
Heavy Industry
Commercial
Public Health &Safety …
ABCD0001 0.0 0.0 1.0 0.0 0.0
ABCD0002 0.0 0.0 0.8 0.2 0.0
ABCD0003 0.5 0.4 0.0 0.0 0.1
ABCD0004 1.0 0.0 0.0 0.0 0.0
ABCD0005 1.0 0.0 0.0 0.0 0.0
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Unit configuration: Customer classes
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Selecting Extended Reserve
Minimise objective =
relay cost + flex relay cost + interruption cost
+ block penalty + fast relay cost – fast relay benefit
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Objective Function
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Selecting Extended Reserve
Block 1(EIH 0.278)
Block 2 (EIH 0.136)
Block 3(EIH 0.054)
Block 4(EIH 0.032)
Type A: Standard
$4,000+ $0
+ $4,420= $8,420
$4,250+ $0
+ $2,162= $6,412
$4,250+ $0
+ $859= $5,109
$4,350+ $0
+ $509= $4,859
Type B: Flexible
$4,000+ $500
+ $4,420= $8,920
$4,250+ $500
+ $2,162= $6,912
$4,250+ $500+ $859
= $5,609
$4,350+ $500+ $509
= $5,359
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Cost varies across reserve type and block
Example of costs for demand unit ABCD0004Assume Block 1, 100% residential, average demand 1MW
Most likely to be used
Least likely to be used
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Selecting Extended Reserve
Minimise objective =
relay cost + flex relay cost + interruption cost
+ block penalty + fast relay cost – fast relay benefit
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Objective Function
Selecting Extended Reserve
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Penalties – finding the Goldilocks Zone
Max
Min
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Selecting Extended Reserve
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Constraints
Block 4
Block 3
Block 2
Block 1
0 2 4 6 8 10 12
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Selecting Extended Reserve
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Constraints
Block 4
Block 3
Block 2
Block 1
0 2 4 6 8 10 12
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Selecting Extended Reserve
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Constraints
Block 4
Block 3
Block 2
Block 1
0 2 4 6 8 10 12
Output
Identifier Allocated Flexible Armed Standby …
ABCD0001 Y Y Y N
ABCD0002 N N N N
ABCD0003 Y N N N
ABCD0004 Y N N Y
ABCD0005 N N N N
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Procurement schedule
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Summary
• Overview- Scheme- System
• Inputs- Unit load- Unit configuration
• Objective function- Meet block targets- Minimise cost
• Output- Procurement schedule
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Questions?
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