In order to have stable and improve efficiency in power supply, there is need to analyse and understand the complex interrelated factors affecting the efficiency and stability of power supply. The factors that affect the efficacy and stability of power supply in any developing country/region could be classified as follows: government policy; economy factor; natural factor; society/community factor; effective energy management; skilled personnel; efficient technology and security factor. All these factors mentioned above have direct or indirect influence on the stability and efficiency of power supply. Various numbers of complicating factors that can prevent restructuring of energy sector to create electricity market that can improve efficiency of power supply in Nigeria are analysed. Suggestions of steps or actions that should be taken into consideration before proposing solutions to some of the problems of power sector are also highlighted in this paper.

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Existing single phase induction motors exhibit low starting torque. Moreover, during accelerating time and at steady state, they produce a significant level of torque pulsations which gives rise to noise and vibration in the machine. As part of efforts to mitigate these problems, a performance improvement strategy using a PWM inverter to drive the existing motor is implemented in MATLAB/Simulink environment in this work. The drive supplies variable voltage and phase to the auxiliary winding with the aid of a pulse width modulation (PWM) technique and a PID controller. Simulation results show the starting torque of the motor increased by 75% under the developed drive scheme. In addition, torque pulsations reduced from 1.4 Nm peak-peak to 0.14 Nm peak-peak at steady state. It was observed that the accelerating time reduced by 30% compared to the accelerating time under line operation. The strategy eliminates the need for series-connected capacitors thereby potentially enhancing the reliability of the motor.

The effect of outages in transmission lines and generator units can be predictable for stable and reliable operation of power system through contingency assessment. Hence, contingency assessment is an important task for stable and effective operation of power system. In this paper, a method of placement of interline power flow controller (IPFC) based on the probability of severity has been proposed. Contingency ranking of lines has been done using Composite Severity Index which is a probabilistic based strategy for the placement of IPFC. IPFC is placed on the line with highest probability of severity during the occurrence of different outages. Thereafter, the size of the IPFC was optimized using cuckoo search algorithm. The proposed methodology has been applied on the IEEE 14 bus system data and results presented. The system overall CSI, active and reactive power were reduced by 7.31%, 10.17% and 14.46% respectively. The results show that optimal placement of IPFC effectively reduces line congestion, improves voltage stability and reduces the active and reactive power loss of the system.Keyword- Power Flow, line utilization factor, severity index, Contingency Management