INTELLIGENCE FUNCTION

Intelligence Function



Intelligence Function

1.Only two factors are needed for an intelligence function to exist: power and

competition. Discuss.

In the last decades, Electrical Power Systems (EPS) have enlarged to meet a growing demand for electrical power. They also become more interconnected and difficult to operate, especially after deregulation, which reduced the cooperation and increased the competition among agents.

Thus, the tasks of operating, planning and protecting these systems can no longer be held in the traditional form. The protection of EPS should take into account that the topology and the loading of these networks are constantly changing, requiring adaptive techniques to improve its effectiveness. Otherwise, the protection of the system may become useless for certain fault situations.

The concept of adaptive protection is presented as a philosophy that adjusts the protection devices to suit the varying conditions of the electrical system . The use of adaptive protection is feasible when digital relays are applied, considering their ability to change their setting on-line and processing speed. However, some aspects may be improved with the use of Artificial Intelligence (AI) techniques in conjunction with such devices.

Several AI techniques have been proposed to solve problems related to the area of protection of electrical systems. Numerous works can be found in the literature with promising results . Some AI techniques are more applicable than other as far as adaptive protection is concerned. This paper will firstly present some AI techniques that are currently being used to implement adaptive strategies to protect EPS. In the sequence other AI techniques are discussed in order to highlight features in certain applications of power system protection.

Some microprocessed protection devices allow the configuration of groups of protection settings. Artificial intelligence techniques can be used to optimize these settings and the logic that defines which group should be active during the online operation of the protection system. Another factor that benefits the adaptive strategy is the use of dedicated computer networks in electric energy utilities, increasing the reliability of communication means.

protection are for the protection of transmission lines. Their use provides advances in the performance of distance relays.

Distance relays operate by calculating a quantity (impedance, reactance, etc.) that, in the presence of faults, is proportional to the distance from the transmission line terminal to the point of the short circuit. The authors in propose a Multilayered Perceptron (MLP) network, trained using known cases and the Back-Propagation algorithm. The choice for ANNs is due to four factors that directly influence the function of distance protection:

• There are adverse effects of uncontrollable variables such as the fault resistance, reactance and location.

• The X/R ratio of the source.

• Pre-fault load flow also affects the apparent impedance seen by the relay.

• Infeed from the line terminals According to the above factors, it is evident that this is a problem of pattern recognition and the use of ANN is indicated. The results obtained by the researchers show a significant improvement in the selectivity of distance relays.

Another important area where many applications of ANN are found is equipment ...