|
Therein lies the problem. Your
optimization procedure, as formulated, has no say on the resulting
voltages. I can think of two suggestions for dealing with this:
1) Instead of a power flow, use an OPF with all non-slack
generators' active power outputs fixed to whatever values were
assigned by the optimization algorithm at the current iteration
(set Pmin=Pg=Pmax for those generators). What this will do is
essentially a reactive redispatch which will try to comply with
voltage limits, generation limits and transmission limits. You
can expect the slack generation to vary a little bit to compensate
for the differing amount of losses.
2) Include the reactive generation variables in your formulation
and continue using a simple load flow.
carlos.
Mohamed Shaheen wrote:
No, I don't
Do you
include reactive generation in the decision variables of
your formulation? If you don't, then your optimization
algorithm does not really have much impact on voltages.
carlos.
Mohamed Shaheen wrote:
I'm currently using penalty functions with
GA and Tree-Seed, But after running Tree-Seed algorithm
including 'runpf' inside, All solutions have violations
and the algorithm chooses the minimum of these solutions
which is also a false solution.
![]() ᐧ
Rather,
it seems that your optimization method should take
into account any constraint violation and fix the
issue by itself. In some methods, such as GA, one
way to do this is by using penalty functions on
constraint violations.
carlos.
Mohamed Shaheen wrote:
I need to enforce limits, but I aim
to get the optimal solution and best parameters
using another optimization method called 'Tree
Seed' and compare it with 'Genetic Algorithm'
after running normal power flow, So I'm not
seeking the optimal solution using
Matpower itself.
Can Matpower help to do this?
![]() ᐧ
The power flow problem solved by runpf does not take
into account voltage limits. If you need to
enforce limits, you can use an appropriately
constrained OPF.
In this case, it just so happens that
the initial voltage specified for bus 31
in the case57.m file happens to be the
voltage at the power flow solution.
Ray
Dear Sir,
Regarding the case57, the
voltage of bus 31 is 0.936 p.u
which is less than the min.
limit of bus voltage (0.94).
Every time I run 'runpf', the
voltage value is 0.936 and it
doesn't change although it is a
PQ bus.
I need your help, please.
Regards,
Mohamed Shaheen.
Msc. student at Ain Shams
University in Egypt
Teaching Assistant in Future
University in Egypt
![]() ᐧ
|
