개선된 공간벡터형 히스테리시스 전류제어기법

Modified Space-Vector Modulation Hysteresis Current Control Method

This paper proposes a modified hysteresis current control method based on space vector modulation. The proposed method differs from former works in that it uses effective voltage vectors instead of zero vectors while not significantly increasing the circuit complexity. The circuit uses outer band that is slightly wider than the usual current limit band (inner band) to detect the phase of current command and thereby the region information. The comparator output signals associated with the inner and outer band are used to determine the proper voltage vector that minimizes the current error and number of switching, with simple logic circuitry. The utilization of effective voltage vector is of particular importance when the ac-side emf is relatively large. Both the simulation and experiment show that the proposed method is more effective than the conventional one that uses zero vectors, in reducing the number of switching over a range of ac-side emf variation.