Designing of a Reduced Switch MLI-Based Standalone Solar Inverter Suitable for Water Pump Application

Abstract

Designing of a reduced switch multi-string cross-connected source type multilevel inverter (CCS-MLI)-based solar pump is introduced in this article. Integration of the Photovoltaic (PV) system with the inverter is achieved through a DC–DC converter equipped with maximum power point tracking (MPPT) to enhance overall reliability. The asymmetrically switched CCS-MLI utilizes only 8 switches to generate 13-level waveform and facilitates power control between battery-assisted PV panels and the single-phase Induction Motor (IM). Multicarrier Pulse Width Modulation (MCPWM) is employed for frequency and fundamental component control in the output voltage. Solar-powered drive systems face the challenge of maintaining intended motor operation amid varying power generation from the PV array. The addition of batteries through a bidirectional DC/DC converter, mitigates this issue by supporting the load during reduced power output from PV panels due to unpredictable solar irradiation levels. Besides ensuring power quality, the proposed control technique realizes constant (V/f) control enabling stable drive operation. The efficacy of the proposed scheme is tested in MATLAB SIMULINK platform with a solar battery combination, considering changing environmental conditions. Furthermore, a hardware prototype of the battery-assisted CCS-MLI-based solar inverter is implemented, and various results are rigorously tested and analyzed using an equivalent machine circuit.

KEYWORDS:

• Asymmetrical DC sources
• Battery-assisted system
• Bidirectional converter
• Power quality
• PV system
• Reduced-switched MLI
• Water pump

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Notes on contributors

Shubhajit Pal

Shubhajit Pal received his MTech degree from Jalpaiguri Government Engineering College, India, in 2014 and worked as an assistant professor at the University of Engineering and Management (Jaipur) until 2019. Currently, he is pursuing a PhD degree from the Indian Institute of Technology (Roorkee). His research interests include multilevel converter topologies and control, industrial drives, and renewable energy integration.Email: [email protected]

Avik Bhattacharya

Avik Bhattacharya is from Kolkata, West Bengal. He received his MTech degree in machine drives and power electronics and PhD in power quality from IIT, Kharagpur, in 2005 and 2010, respectively. Currently, he is working as an assistant professor at the department of electrical engineering, Indian Institute of Technology (Roorkee). He is the author of many papers published in national and international journals and conferences. His research areas include power quality, AC-DC micro-grids, solid-state transformers, direct and indirect matrix converters, FACTS devices, electric machines, power electronics, electric drives, and electric vehicles.

Rubell Sen Goopta

Rubell SenGoopta completed his PhD in power electronics from IIT Roorkee, India in October 2022. Currently, he is working as an associate professor and head of EEE at Chittagong Independent University, Chattogram, Bangladesh. He is also the Dean of Engineering School at CIU. His research interests include power electronics, control systems, renewable energy technology, and electric vehicles. He published many articles and presented papers at national and international levels.Email: [email protected]