Reduced capacitor voltage stress and soft-start capability by adding new ZSI for PMBLDC

Abstract

The recently proposed Z-Source inverter (ZSI) is an important improvement to Z-Source inverter (ZSI), which greatly reduces the passive component stress. This paper presents a PMBLDC motor which based on the highperformance Z-source inverter It can overcome limitations of capacitor voltage stress. The proposed modified Z-source inverter with reduced capacitor voltage stress and soft start capability for PMBLDC can operate at wide range load (even no-load) with small inductor which is very suitable for PMBLDC motor, eliminate the possibility of the DC-link voltage severances, simplify the Z-source network inductor and controller design, increase the inverter section pattern, thus, decrease the capacitor voltage stress and soft start capability by changing the magnitude and distribution of the harmonics and then decrease the iron loss of the motor. The control strategy of the proposed Z-source inverter is exactly used as the Fuzzy controller & Compared with PI controller, so all the control strategy can be used directly. A smooth-start strategy is also proposed to suppress the inrush surge and the resonance of Z-source capacitors and inductors.