A three-stage process for making a harmonic resonance mitigation decision in an end-user power plant is developed. Two new indices are developed to assist in making the decision. The first index assesses the severity of resonance and the second is used to make a mitigation decision. In Stage 1, a quantitative model is developed to structure and represent the decision problem with the harmonic resonance severity index as the objective function. In Stage 2, "Utility Theory" is used as the decision criterion to select the most desirable capacitor size. In Stage 3, the mitigation index is applied to assess whether mitigation is needed or not for the chosen capacitor. A case study, based on a model made up of three end-users is conducted to demonstrate the effectiveness of this new process. Index Terms-Decisiontable, decision theory process, mitigation decision, severity of harmonic resonance, utility theory.

This paper presents a broader analysis approach which adds to the traditional fault analysis technique commonly used in industry to size and select circuit breakers required for the power system. The fault analysis has been simulated on a computer software program DIgSILENT PowerFactory for all fault conditions. The circuit breaker selection will be based on a Multi-Criteria Analysis which helps to evaluate the design to arrive at the most user preferred result. This approach is refined to incorporate user preferences with respect to the criteria so that the final design is representative of both the design specification and the concerns of the user. This broader newer approach has been shown by means of case studies to be effective

This paper investigates the effectiveness of two types of passive filters used for harmonic mitigation in a power system containing multiple capacitors and harmonic sources that cause multiple resonance points. They are notch and second order types installed at the point of common coupling (PCC) and include the utility capacitor bank as a component in their designs. Traditionally, the focus is only on mitigating total harmonic distortions (THDv & THDi). In this study their effectiveness is extended to evaluate the impact of these filters in terms of Total Power, Efficiency and Severity of Resonance factors when an unacceptable distortion is present. The effectiveness is investigated using the SUPERHARM/TOP software package. Computer models are developed to conduct harmonic penetration and harmonic scan resonance studies. Case studies are conducted for a network without a filter, with a notch filter and then with a second order filter. The filters are analysed at the input to the network and effectiveness factors are used to evaluate efficiency.

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