ABSTRACT:
Z-source
inverters eliminate the need for front-end DC-DC boost converters in
applications with limited DC voltage such as solar PV, fuel cell. Quasi
Z-source inverters offer advantages over Z-source inverter, such as continuous
source current and lower component ratings. In this paper, switching table
based Direct Torque Control (DTC) of induction motor fed by quasi Z-Source
Inverter (qZSI) is presented. In the proposed technique, dc link voltage is
boosted by incorporating shoot through state into the switching table. This
simplifies the implementation of DTC using qZSI. An additional DC link voltage
hysteresis controller is included along with torque and flux hysteresis controllers
used in conventional DTC. The results validate the boost capability of qZSI and
torque response of the DTC.
KEYWORDS:
1. DTC
2. qZSI
3. DC-DC
Converter
4. DC
Link Voltage
5. Hysteresis
Controller
SOFTWARE: MATLAB/SIMULINK
BLOCK DIAGRAM:
Fig. 1: Block Diagram for DTC using Qzsi
EXPECTED SIMULATION RESULTS:
Fig. 3: Stator Phase 'a' Current
Fig. 4: Speed vs. Time
Fig. 5: DC Link Voltage
Fig. 6: Capacitor Voltage, VC1
CONCLUSION:
REFERENCES:
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[3]
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[4]
F. Z. Peng, "Z-source inverter, " IEEE Trans. Ind. Appl., vol. 39, no.
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[5]
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