Aiming at the problem of unobservable areas of neutral current in conventional space vector pulse width modulation for T-type three-level inverters

a hybrid pulse width modulation-based phase current reconstruction strategy is proposed. First

the sampling mechanism of the neutral current and the formation mechanism of unobservable areas are analyzed

and the unobservable areas are classified according to the minimum sampling time. Second

based on the principles of volt-second balancing and composite zero vector

different compensation voltage vectors are inserted into the unobservable areas to compensate for the observable duration of the observable voltage vectors. Meanwhile

the original switching sequence is adjusted to offset the effects of the compensation voltage vectors

thereby ensuring that the magnitude and angle of the reference voltage vector remain unchanged. Ultimately

the proposed strategy eliminates the unobservable areas of the neutral current

enabling stable and accurate detection of the neutral current. Experimental results show that the proposed method achieves complete reconstruction of three-phase currents

with the total harmonic distortion of phase currents below 3.30%.