End (AFE) topology based three-phase inverter are presented in this paper. The inverter belongs to Infinite Level (ILI) Multi-level Inverters (MLI) with Reduced Switch Count. The circuit consists of three dc to dc buck converters connected to the individual legs of the six switch three-phase inverter. Three phase output is obtained at the output of the inverter without any external filtering circuit. The dc bus utilization is also improved by using third harmonic injection. The three-phase induction motor is considered as load and performance is evaluated for full load conditions. AFE based ILI reduces the switching and conduction losses as only one switch is switching at high frequency per phase.

Active Front End Topology Based Three Phase Inverter

Direct Torque Control (DTC) of Induction Motors (IMs) is popular in motor drive applications because of its robust and simple control structure. The IM winding can be controlled on both sides using dual inverter technique which more effective for Electric Vehicle (EV) with a greater number of voltage vectors. However, the battery performance of the dual inverter will deteriorate unevenly on both sides, resulting in fluctuating voltages for the EV system. This will lead to the generation of distorted stator currents and a significant droop in the stator flux, which in turn can increase the total harmonic distortion (THD) in the system. Additionally, the performance of torque may not be able to regulate effectively. This paper examines the effect of unstable voltage on voltage vector mapping performance with tilted angles and proposes new sector definitions based on voltage ratio conditions. Moreover, the proposed sector for each predefined voltage ratio is tested under three-speed conditions. The proposed technique effectiveness is validated through hardware experiments using a dSPACE 1104 controller and retuning the stator current for proper waveform. This approach improves the stator current waveform, improves stator flux droop, enhances torque regulation and minimizes the THD in the DTC system. 

Flexible Sector Detector-Based Mismatch Supply Voltage in Direct Torque Control Doubly Fed Induction Machine: An Experimental Validation

For a three-level grid-connected neutral point clamped (3L-NPC) inverter, a closed-loop space vector modulation-based PI controller is presented in this paper. The clamp diodes and cascaded dc capacitors used in the diode-clamped multilevel inverter produce multiple-level ac voltage waveforms. Low THD and creating pure sine waves are the key benefits of MLIs. Generally speaking, the inverter can be set up with a three-level, five-level, seven-level, etc. architecture. However, a NPC inverter is only ever referred to as a 3-level inverter. The SVM is one of the well-liked period modulation techniques and is widely used for the digital management of VSIs. The SVM is principally used for generating change pulses. The project SVM results are compare with carrier-based curved PWM (SPWM). The enforced 3L-NPC simulation results are verified in MATLAB/SIMULINK software.

Grid-Connected 3L-NPC Inverter with PI Controller Based on Space Vector Modulation

End (AFE) topology based three-phase inverter are presented in this paper. The inverter belongs to Infinite Level (ILI) Multi-level Inverters (MLI) with Reduced Switch Count. The circuit consists of three dc to dc buck converters connected to the individual legs of the six switch three-phase inverter. Three phase output is obtained at the output of the inverter without any external filtering circuit. The dc bus utilization is also improved by using third harmonic injection. The three-phase induction motor is considered as load and performance is evaluated for full load conditions. AFE based ILI reduces the switching and conduction losses as only one switch is switching at high frequency per phase. 

The design and performance analysis of an open-ended three-phase induction motor, driven by an Infinite Level Inverter (ILI) with its speed control using scalar and direct vector control techniques are presented in this paper. The ILI belongs to an Active-Front-End (AFE) Reduced-Device-Count (RDC) Multi-level Inverter (MLI) topology. The fundamental structure of this inverter topology is a dc-to-dc buck converter followed by an H-bridge. This topology performs a high-quality power conversion without any shoot-through issues and reverse recovery problems. The performance of the proposed topology is validated using a resistive load. The THD of output voltage waveform obtained is 1.2%. Moreover, this topology has exhibited a high degree of dc-source voltage utilization. ILI considerably reduces the switching and conduction losses, since only one switch per phase is operated at high frequency, and other switches are operated at power frequency. The overall efficiency of the inverter is 98%. The speed control performance of the ILI topology using three-phase open-ended induction motor has been further validated through scalar and direct vector control techniques. Results obtained from simulation studies are verified experimentally.

A Hareesh

Papers

Scalar and Vector Controlled Infinite Level Inverter (ILI) Topology Fed Open-Ended Three-Phase Induction Motor