Abstract:
Electrical energy is critical to a country's socioeconomic development. The penetration of
distributed generation (DG) into the electrical distribution network has economical, technical and
environmental advantages. It is a dependable solution for addressing the power system profile's
primary concerns, like load increase, supply performance and dependability. Renewable type DG
units (such as wind turbine and solar photovoltaic) have been integrated in the radial distribution
system. Moreover, it has been proven that the additional benefits brought by DG could be
substantial if it is optimally placed and sized in the distribution network. The major problems
deal in this thesis is the existence of high real power losses and weak voltage profiles. The thesis
minimizes active power loss and improves voltage profile by using DGs. To achieve this
researcher had got new novel method. It was voltage stability index based forward backward
sweep with power summation method with Genetic algorithm approach used to allocate and size
DGs at the appropriate location(s) along the feeder of weakest candidate buses of the system.
The appropriate location(s) is decided by voltage stability index and power flow analysis. This
technique places one DG at a time on a low voltage stability index node. After that, it calculates
the size of the DG corresponding to that bus. For more than one DG no need to use voltage
stability index, it can directly use forward backward sweep with power summation method and
genetic algorithm to allocate in appropriate location with suitable size until the specified
stopping criterion has reached. In this thesis for comparison purpose load flow analysis for DG,
that can inject active power only and DG that can inject both active and reactive power had done.
It focused on the comparison of DG type and number. The percentage reduction in real power
loss was 60.78% and 85 % while the percentage of reactive power loss reduction was 61.019%
and 85.57% for two DG which supply real power only and two DG which supply both real and
reactive power respectively. The voltage profile of standard IEEE 33 bus system was generally
improved with lowest bus voltages profile of 0.9260352 and 0.9865168 p. u in the two cases
respectively. As a result, the best solution is the integration of two DG which supply active and
reactive power. Total active power loss recorded in feeder has minimized to 49.2 kW from 327.8
kW and total reactive power loss minimized to 44.6 kVAR from 309.1 kVAR. Same way all the
weak voltage profiles have also optimized to the standard ±5% voltage deviation level.
Estimation costs of components were made according to homer pro-optimizer software.
