Design and Implementation of Multilevel Inverters for Electric Vehicles

C Dhanamjayulu,Vigna K Ramachandaramurthy,Jens Bo Holm-Nielsen,Frede Blaabjerg,Sanjeevikumar Padmanaban

doi:10.1109/access.2020.3046493

C Dhanamjayulu, Vigna K Ramachandaramurthy + Show 3 more

Open Access

https://doi.org/10.1109/access.2020.3046493

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Abstract

The efficient and compact design of multilevel inverters (MLI) motivates in various applications such as solar PV and electric vehicles (EV). This paper proposes a 53-Level multilevel inverter topology based on a switched capacitor (SC) approach. The number of levels of MLI is designed based on the cascade connection of the number of SC cells. The SC cells are cascaded for implementing 17 and 33 levels of the output voltage. The proposed structure is straightforward and easy to implement for the higher levels. As the number of active switches is less, the driver circuits are reduced. This reduces the device count, cost, and size of the MLI. The solar panels, along with a perturb and observe (P&O) algorithm, provide a stable DC voltage and is boosted over the DC link voltage using a single input and multi-output converter (SIMO). The proposed inverters are tested experimentally under dynamic load variations with sudden load disturbances. This represents an electric vehicle moving on various road conditions. A detailed comparison is made in terms of switches count, gate driver boards, sources count, the number of diodes and capacitor count, and component count factor. For the 17-level, 33-level, and 53-level MLI, simulation results are verified with experimental results, and total harmonic distortion (THD) is observed to be the same and is lower than 5% which is under IEEE standards. A hardware prototype is implemented in the laboratory and verified experimentally under dynamic load variations, whereas the simulations are done in MATLAB/Simulink.

Highlights

With the demand for an increase in the requirements of highpower quality in industrial applications and solar PV systems, the conventional inverters in meeting the desired conditions like a pure sine-wave output and less harmonic distortions is a challenging task
The recent multilevel inverter topologies comprise a smaller number of components used in the circuit compared with the conventional inverters such as flying capacitor type (FC) [2], cascaded H-bridge type (CHB) [3], and the neutral point clamped type (NPC) [4]
perturb and observe (P&O) algorithm based maximum power point tracking (MPPT) technique is used, the stable output is achieved under all circumstances

Summary

INTRODUCTION

With the demand for an increase in the requirements of highpower quality in industrial applications and solar PV systems, the conventional inverters in meeting the desired conditions like a pure sine-wave output and less harmonic distortions is a challenging task. At any point during the operation of solar PV, the maximum extraction of power can be done This can be possible with an efficient MPPT technique that tracks the irradiation and temperature and provides a constant voltage at the output. In mode-3 operation, the switches SD, S3, S7, SE, S11, SH, S9, S1, SB, SA, D1, S5 turn on forming a load current path where V2, VC2, V3, VC3, V4, and VC4 sources act in the circuit and produce the voltages of 75V, 75V, 25V, 25V and 75V respectively and get a voltage of 14Vdc equal to 350V. In mode-28 operation, the switches D1, S6, S5, S4, S3 turn on forming a load current path where the -V1 source acts in the circuit and produces the voltage of -15.4V and gets a voltage of -Vdc equal to -15.4V.

COMPARISON STUDIES

Findings

CONCLUSION