The effects of load frequency control (LFC) of interconnected distribution power system in tie-line substation area load –frequency stability and the frequency respond at distribution generator (DG) are very important for interconnected control power system of tie-line area. The generating power system of solar farm and wind turbine which have interconnected distribution power system in tie-line substation area were tested using 3 simulation parameters: non-controller Automatic Voltage Regulator (AVR) and with Pl Controller. The results showed that there were 3 types of load and frequency changing in the interconnected area: load changed 0.02 p.u. had frequency of load changed 0.025 Hz and large disturbance. Comparisons of load-frequency to respond for steady state the time respond was 7.9 seconds for non-controller 5.4 seconds for AVR and 1.7 seconds for under controlled system at 0.1 p.u using Pl controller. Therefore the Pl controller has better efficiency than non-controller about 31 % and AVR about 16%. It can be concluded that the interconnected distribution power system in tie-line substation area controlling for storage for connected grid had better efficiency and optimization of generating power from renewable solar farm and wind turbine which have interconnected distribution power system in the nearby are balance of controlling of the original system.

A solar energy is most popular renewable energy source which can reduce usage of fuel in thermal generation and impact on environment. The solar energy is a clean and sustainable source. This paper proposed method of finding optimal locating and sizing of PV solar farm on the power system with minimize fuel costs by considering solar radiation in each location of solar farm. The bees algorithm (BA) is used to minimize fuel cost of thermal units by changing location and varying sizes of solar farm with security constraints of power system and solar radiation. IEEE 30 bus test system is used to verify the proposed method. The results show that the proposed method found the optimal position of solar farm with minimum economic cost