Single-phase power active filter using instantaneous reactive power theory – Theoretical and practical approach

The paper deals with the new method of analysis, synthesis and experimentation of single-phase power active filters. By using a new particular transformation theory, the ordinary single-phase system can be transformed into an equivalent two-axes orthogonal one. The new original thought is based on the idea that ordinary single-phase quantity can be complemented by fictitious second phase so that both of them will create an orthogonal system, as is usual in three-phase systems. Application of the above theory makes it possible to use complex methods of analysis as the instantaneous reactive power method, which have not been usable for single-phase systems so far. Both the active and reactive powers can be determined by this method. Practical application of the method is outlined for the case of reference current determination for single-phase power active filter. The paper shows some examples of the simulation verification results, which proved a high accuracy and extremely fast response of the single-phase active filter with control, based on the introduced method. The effectiveness of proposed control algorithm is also demonstrated by experimental results, which were carried out on the single – phase active parallel filter, power rate of 25 kVA and controlled by 32 – bit floating point digital signal processor TMS 320C31.