Chintan Patel

A Nine-Level Inverter Topology for Medium-Voltage Induction Motor Drive With Open-End Stator Winding

A new scheme for nine-level voltage space-vector generation for medium-voltage induction motor (IM) drives with open-end stator winding is presented in this paper. The proposed nine-level power converter topology consists of two conventional three-phase two-level voltage source inverters powered by isolated dc sources and six floating-capacitor-connected <formula formulatype=inline><tex Notation=TeX>

A Multilevel Converter With a Floating Bridge for Open-End Winding Motor Drive Applications

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A dual two-level inverter with a single source for open end winding induction motor drive application

</tex></formula>-bridges. The <formula formulatype=inline><tex Notation=TeX>

Model Predictive Control for a Dual-Active Bridge Inverter With a Floating Bridge

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A hybrid seven-level inverter for IM drive

</tex></formula>-bridge capacitor voltages are effectively maintained at the required asymmetrical levels by employing a space vector modulation (SVPWM) based control strategy. An interesting feature of this topology is its ability to function in five- or three-level mode, in the entire modulation range, at full-power rating, in the event of any failure in the <formula formulatype=inline><tex Notation=TeX>

Nearly constant switching frequency hysteresis current controller for general n-level inverter fed induction motor drive

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Design optimization of integrated rotational inductor for high-speed AC drive applications

</tex></formula> -bridges. This feature significantly improves the reliability of the proposed drive system. Each leg of the three-phase two-level inverters used in this topology switches only for a half cycle of the reference voltage waveform. Hence, the effective switching frequency is reduced by half, resulting in switching loss reduction in high-voltage devices. The transient as well as the steady-state performance of the proposed nine-level inverter-fed IM drive system is experimentally verified in the entire modulation range including the overmodulation region.

Experimental validation of the solid state substation with embedded energy storage concept

This paper presents a three-phase open-end winding induction motor drive. The drive consists of a three-phase induction machine with open stator phase windings and dual-bridge inverter supplied from a single dc voltage source. To achieve multilevel output voltage waveforms, a floating capacitor bank is used for the second of the dual bridges. The capacitor voltage is regulated using redundant switching states at half of the main dc-link voltage. This particular voltage ratio (2:1) is used to create a multilevel output voltage waveform with three levels. A modified modulation scheme is used to improve the waveform quality of this dual inverter. This paper also compares the losses in the dual-inverter system in contrast with a single-sided three-level neutral point clamped converter. Finally, detailed simulation and experimental results are presented for the motor drive operating as an open-loop v /f controlled motor drive and as a closed-loop field-oriented motor controller.

Evaluation of a digitally controlled power electronic emulator for Supercapattery

This paper describes a dual inverter motor drive topology using a single supply for open winding induction machine. The paper considers the possibilities of using a dual bridge inverter with one bridge inverter floating, this will allow achieving multilevel voltage output. The charging and discharging of the floating capacitor can be controlled using the redundant switching states. The use of this topology can improve the system weight and volume. The paper includes analysis and modulation of the converter topology as well as simulation and experimental results.

Direct torque control scheme of IM drive with 12-sided polygonal voltage space vectors

This paper presents a model predictive control technique applied to a dual-active bridge inverter where one of the bridges is floating. The proposed floating bridge topology eliminates the need for isolation transformer in a dual inverter system and therefore reduces the size, weight, and losses in the system. To achieve multilevel output voltage waveforms, the floating inverter dc-link capacitor is charged to the half of the main dc-link voltage. A finite-set model predictive control technique is used to control the load current of the converter as well as the floating capacitor voltage. Model predictive control does not require any switching sequence design or complex switching time calculations as used for space vector modulation; thus, the technique has some advantages in this application. A detailed analysis of the converter as well as the predictive control strategy is given in this paper. Simulation and experimental results to validate the approach are also presented.