Applications of fuzzy logic in the estimation of power electronic waveforms

The application of fuzzy logic in the estimation of power electronic waveforms is explored. The distorted line current waves in a triac light dimmer and three-phase diode rectifier feeding an inverter-machine load have been taken into consideration, and fuzzy logic has been applied to estimate the RMS current, fundamental RMS current, displacement factor, and power factor. Two methods have been considered in the estimation, i.e., a fuzzy rule-based approach and a fuzzy relational or Sugeno's approach. The results of the estimation have been compared with the actual values, and indicate good accuracy. The fuzzy estimation has the advantages of fast response, multiple outputs from the single premise of a rule, and immunity of noise and drift in the sensors of the two estimation methods, the relational approach has fewer rules, gives better accuracy, and the algorithm development is less laborious.<>