Effect of DC Link Control Strategies on Multiterminal AC-DC Power Flow

Table 7

Steps to compute active and reactive power injections in control strategies 1 and 5.

(a)

Control strategy 1
Specified quantities	Unknown quantities
Step 1: compute and using DC load flow
Step 2: compute
Step 3: compute
Step 4: compute
Step 5: compute
Step 6: compute
Step 7: compute
Step 8: compute
Step 9: compute
Step 10: compute
Step 11: compute
Note:   and   are specified. , , , and can be computed prior to the AC power flow and hence
are independent of the iterative loop.

(b)

Control strategy 5
Specified quantities	Unknown quantities
Step 1: compute and using DC load flow
Step 2: compute
Step 3: compute
Step 4: compute
Step 5: compute
Step 6: compute
Note 1:   is an AC power-flow variable and is updated in every iteration. Hence, changes in every iteration.
Step 7: compute
Step 8: compute
Step 9: compute
Note 2:   and   are also AC power-flow variables and are updated in every iteration, along with and .
Step 10: compute
Step 11: compute
Note 3:   and   are specified. can be computed prior to the AC power flow. However, , , and depend upon
, , and , respectively, and need to be updated in every iteration.