Mobile QR Code QR CODE : The Korean Institute of Power Electronics
Title Average Phase Current Estimation Method using a DC Link Shunt Resistor in the Three-Phase Inverter
Authors Hyun-Keun Ku ; Han-Beom Yeom ; Jang-Mok Kim
DOI 10.6113/TKPE/2016.21.4.343
Page pp.343-350
ISSN 1229-2214
Keywords Average current; Current reconstruction; Current estimation; DC link current; Single-shunt inverter
Abstract Generally, the average phase current is sampled at the midpoint of a PWM signal for the vector control of an AC motor. The three-phase current can also be reconstructed from a DC?link shunt resistor by sampling the shunt voltage during the active vectors of the SVPWM. However, the reconstructed current is different from the average current because of the deviation of the sampling point from the midpoint of the PWM signal. This paper proposes an algorithm to estimate the average current from the reconstructed current in a single-shunt inverter. The proposed method is derived from the phase current slopes based on switching states and corresponding switching time. In addition, the proposed method is generalized for all the six sectors of the space vector hexagon. The validity of the proposed algorithm is verified with simulations and experiments.