Active power line conditioners: an approach using intelligent systems

Power factor, nowadays, is a critical matter. The ever increasing utilization of power electronics in all kinds of industry applications and the severe standards requirements are pushing the research toward new solutions to keep the industrial power factor around certain values. Switched capacitors banks bring together problems that are not easy to solve, such as parallel resonance and overvoltage. This article describes the application of a hybrid power converter as an active line conditioner. The hybrid converter basically is a power converter bridge with two GTOs that transform it into a fully controllable inverter. Therefore, this power converter allows independent control of voltage and displacement factor. When appropriated controlled, this converter can produce part of the reactive power consumed by the load. Made with a well known technology, this converter is suitable for large power compensation applications. Theoretical analysis and experimental results are presented. A control strategy based on learning is also proposed. This structure, an hierarchical approach, uses hints, coded in fuzzy conditional rules, to train a neural network responsible for power converter variables manipulation.