Abstract

This paper presents the three – level neutral point diode clamped inverter is used in a distribution static compensator (DSTATCOM), making use of the multi-level inverter advantages of low harmonics distortion and reduced switching losses. The pulse width modulation (PWM) inverter is employed as DSTATCOM compensating reactive power and eliminates the harmonics drawn from a non-linear load. A fuzzy gain scheduled proportional and integral (FGPI) dc voltage controller is proposed for inverter dc voltage control to improve the performances of three – levels DSTATCOM and fuzzy logic current controller is proposed to reduce harmonic supply currents for DSTATCOM. The D-Q reference frame theory is used to generate the reference compensating currents for three -level DSTATCOM. The three-level DSTATCOM with proposed control schemes is implemented in Matlab/Simulink software platform. The simulation results show that the system with proposed control schemes provides a good inverter dc voltage regulation, reduced harmonics distortion in supply current and in phase with line voltage.

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