Control and Design of Microgrid Components - Power Systems ...

Chapter 7. Microgrid Tests
There are two fundamental different circuits where the test is performed depending on the
relative locations of the two units. These two circuits are the series and the parallel
configurations. Figure 7.1(a) shows the series configuration, while Figure 7.1(b) shows the
parallel configuration. Both configurations are achieved with the same hardware equipment,
appropriately rearranged. Each of the five loads may be included or not in every particular
experiment. To avoid confusion, every experiment will explicitly show the full circuit diagram
used.
(a)
Utility
System
F 1
P 1
4 wire
75yd
4 wire
25yd
P 2
L1
L L
3
L
2
4
L5
F 2
F 1
(b)
Utility
System P1
L 1
L 2
F
2
4 wire
75yd
P
2
L 4 wire
3
L4
25yd
L 5
Figure 7.1 Series (a) and Parallel (b) Circuit Configurations.
Each of the two sources can adopt either unit power (P) control or feeder flow (F) control. There
are a total of four possible control combinations for the two units: PP, FF, PF, and FP. The
circuit with the series configuration will test all these cases, while the parallel configuration will
only test FF and FP. This is no loss of generality. The case PF is symmetric to FP and adds no
useful insight. The case with PP is non dependent on the location of the sources and the loads
and will give the same exact results already obtained for the series configuration. In conclusion,
these are the six groups of tests:
Series configuration:
Unit 1 controls P, Unit 2 controls P
Unit 1 controls F, Unit 2 controls F
Unit 1 controls F, Unit 2 controls P
Unit 1 controls P, Unit 2 controls F
Parallel Configuration
Unit 1 controls F, Unit 2 controls F
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