Original scientific paper It is well-known that shunt active power filter (SAPF) is widely used to reduce harmonic distortion and to compensate reactive power in electrical power systems. DC bus voltage control of SAPF is very important for excellent power quality. In the control of SAPF, DC bus voltage is controlled by conventional control methods such as PI and PID controllers. However, these controllers cannot give good results under transient and steady state conditions. Robust and intelligent controllers are required in order to improve performance of SAPF. In this paper, interval type-2 fuzzy logic system (T2FLS) that does not require mathematical model to be controlled system is preferred for control of DC bus voltage of SAPF and compared with type-1 fuzzy logic system (T1FLS). SAPF structures with both controllers are designed and simulated using MATLAB /Simulink environment. Simulation results have shown that SAPF structure with proposed controller has superior features than T1FLS in terms of fixed DC bus voltage, total harmonic distortion and power quality.
Keywords: Interval Type-2 Fuzzy Logic Controller (T2FLS); power quality; reactive power compensation; Shunt Active Power Filter (SAPF)Robusno reguliranje usporedno aktivnog filtra snage pomoću regulatora neizrazite logike intervala tipa-2 za poboljšanje kvalitete energijeIzvorni znanstveni članak Dobro je poznato da se usporedno aktivni filtar snage (SAPF -Shunt Active Power Filter) uvelike koristi za smanjenje harmonijske distorzije i kompenzaciju reaktivne snage u elektroenergetskim sustavima. Regulator napona sabirnice istosmjerne struje SAPF-a vrlo je važan za odličnu kvalitetu snage. U reguliranju SAPF-a, napon sabirnice istosmjerne struje regulira se konvencionalnim metodama kao što su PI i PID regulatori. Međutim, ti regulatori ne mogu dati dobre rezultate u prijelaznim i stacionarnim uvjetima. Robusni i inteligentni regulatori potrebni su za poboljšanje performansi SAPF-a. U ovom radu, sustav neizrazite logike intervala tipa-2 (T2FLS) koji ne zahtijeva matematički model kao kontrolni sustav preferira se za reguliranje napona sabirnice istosmjerne struje SAPF-a i uspoređuje sa sustavom neizrazite logike tipa-1(T1FLS). Konstruirane su i simulirane strukture SAPF-a s oba regulatora primjenom MATLAB /Simulink okruženja. Rezultati simulacije su pokazali da SAPF struktura s predloženim regulatorom ima bolje karakteristike od T1FLS-a u odnosu na fiksni napon sabirnice istosmjerne struje, ukupno harmoničko izobličenje i kvalitetu snage.Ključne riječi: kompenzacija reaktivne snage; kvaliteta snage; regulator neizrazite logike intervala tipa-2; usporedno aktivni filtar snage