In a de-regulated open access environment, reactive power is one of the ancillary services which must be provided by an Independent System Operator (ISO). In this paper, a new algorithm is proposed in which reactive power resources are initially so tuned that optimum security in terms of voltage profile and voltage stability are achieved while at the same time, the system losses are minimized. ...

In a de-regulated open access environment, reactive power is one of the ancillary services which must be provided by an Independent System Operator (ISO). In this paper, a new algorithm is proposed in which reactive power resources are initially so tuned that optimum security in terms of voltage profile and voltage stability are achieved while at the same time, the system losses are minimized. ...

A new voltage stability control model was presented to guarantee the static voltage stability of power system using the active power constraints of weak branches as the static voltage stability margin constraints. A local index for voltage stability was used to recognize the key contingencies, the weak branches and their maximum active power. Based on DC power flow equations, a static security ...

Based on reactive power-voltage characteristics analysis of air conditioners, the effects of air conditioner load on voltage stability of an urban power system are investigated in this paper. Indexes for evaluating bus voltage security are proposed, and static voltage stability analysis method is adopted. The computational analysis of a real urban power system in East China shows that air condi...

application of distributed generation (dg) units in distribution networks has increased in recent years. sizing and sitting of dg units are two important factors which should be considered, especially for reduction of power losses in distribution system. this paper presents a new approach for dg placement in distribution systems using the mixed integer nonlinear programming (minlp). this approa...

The management of power systems has become more difficult than earlier because power systems are operated closer to security limits, environmental constraints restrict the expansion of transmission network, the need for long distance power transfers has increased and fewer operators are engaged in the supervision and operation of power systems. Voltage instability has become a major concern in ...

this paper presents a cooperative control which is applied to the secondary control of a microgrid controlled via a multi-agent scheme. balancing power that leads to voltage and frequency stability in a microgrid is essential. the voltage and frequency regulations are limiting within the specified limits and conveying them to their nominal values. limiting and conveying the voltage and frequenc...

Due to the continuous increment of the load demand, identification of weaker buses, improvement of voltage profile and power losses in the context of the voltage stability problems has become one of the major concerns for the larger, complex, interconnected power systems. If the voltage profile of the weaker buses is improved, the voltage stability can be improved significantly. Because of the ...