International Journal on Electrical Engineering and Informatics - Volume 14, Number 2, June 2022 Dynamic Performance of DC-DC-AC Boost Switched Capacitor Converter Fed Single Phase Induction Motor Crescent Onyebuchi Omeje Department of Electrical/Electronic Engineering, Faculty of Engineering, University of Port Harcourt, Choba, Port-Harcourt, Rivers State, Nigeria crescent.omeje@uniport.edu.ng Abstract: Single phase induction motor mostly exhibits a low starting torque and also produces a significant level of torque pulsations during a steady state acceleration time. These drawbacks can be mitigated using an improved drive strategy. The drive scheme applied in this work employed a DC-DC-AC boost switched capacitor converter to drive a 0.25 horse power single phase induction motor at a regulated duty cycle of 0.5 and 0.75. The motor was simulated under steady state and transient state at a varying load torque of 0-22.5Nm. The converter topology integrates the inductive switching cell with a switched capacitor in performing a direct energy conversion at a high output voltage gain. A simulation process carried out on the complete drive model showed that an enhanced starting torque and a speed regulation values of 0.2255 and 0.9271 were obtained at 0.5 and 0.75 duty cycle under steady state whereas 0.2094 and 0.2096 were obtained under transient state. The results obtained also showed that different efficiency values of 82.86% and 76.79% were achieved at 0.75 and 0.5 duty cycle. A stable motor operation with an improved voltage gain, appreciable power output and reduced torque pulsations were achieved at 0.75 duty cycle. All simulation processes were accomplished in MATLAB/SIMULINK 2014. Keywords: DC-DC-AC Boost Converter, Duty-Cycle, Single-Phase Inverter, Single-Phase Induction Motor, Speed and Torque control, Voltage-gain. 1. Introduction Switched capacitor converters (SCC) are mostly applied in single phase low-voltage electronic circuit due to the obvious simplicity and high rate of energy conversion process [1]. The first circuit topology involving SCC was applied in voltage doublers circuit and presented in [2-3]. Other topologies that are aimed at improving the efficiency of the electrical device at higher voltage gains are also presented in [4-5]. Pure ac-ac switched capacitor converters have been developed for three phase systems with good performance and proven portability as reported in [6-8]. The hybrid boost switched capacitor converter has been deployed in dc-dc converter systems and referenced in [9-12]. However, the use of switched capacitor converter (SCC) in ac-ac conversion system has not previously gained wide range of applications due to inherent switching losses and unwarranted communication stages. The DC-DC-AC boost switched capacitor converter applied in this paper provides a high voltage gain, an appreciable output power and an output voltage which is approximately five times the value of the input voltage. The main objective of this paper is to derive an optimal supply voltage that can drive a single phase induction motor with a good speed regulation, reduced losses and an enhanced efficiency. The circuit topology is presented in Figure 1. It is a combination of a boost converter with a switched capacitor connected single phase inverter powered load which can either be a resistive load or an induction motor. Received: April 13 rd , 2022. Accepted: June 25 th , 2022 DOI: 10.15676/ijeei.2022.14.2.13 465