Novel single phase pwm ac–ac converters solving commutation problem using switching cell structure and coupled inductor
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This document introduces a novel single-phase PWM AC-AC converter design that effectively addresses commutation issues using a switching cell structure and coupled inductors. The proposed system maintains stable operation even under highly distorted input voltages, offering advantages over conventional methods by not requiring voltage or current polarity sensing for commutation. The converters are suitable for applications such as AC drives and wind power systems.
Novel single phase pwm ac–ac converters solving commutation problem using switching cell structure and coupled inductor
- 1. Do Your Projects With Domain Experts… Copyright © 2015 LeMeniz Infotech. All rights reserved Page number 1 LeMeniz Infotech 36, 100 Feet Road, Natesan Nagar, Near Indira Gandhi Statue, Pondicherry-605 005. Call: 0413-4205444, +91 9566355386, 99625 88976. Web : www.lemenizinfotech.com / www.ieeemaster.com Mail : projects@lemenizinfotech.com Novel Single-Phase PWM AC–AC Converters Solving Commutation Problem Using Switching Cell Structure and Coupled Inductor Abstract For AC–AC power conversion, the conventional approach is to use a diode or PWM rectifier followed by a PWM voltage- source inverter with a DC link. Other approaches include phase- controlled ac–ac converters employing thyristors, matrix converters, and so on. The output voltage and frequency can be varied with these structures. However, for applications where only voltage regulation is required, direct PWM ac–ac converters are a more practical choice in terms of cost and size. Existing system The switches S2 and S3 are both turned ON and OFF simultaneously, and they are complementary to the switches S1 and S4 in an ideal case. However, due to the different time delays and limited switching speed of the switching devices, there inherently exists a short dead-time or an overlap-time between switches. During the dead-time, there is no current path for the output filter inductor (Lo), so the switches may be damaged by excessive voltage. Similarly, the switches may be
- 2. Do Your Projects With Domain Experts… Copyright © 2015 LeMeniz Infotech. All rights reserved Page number 2 LeMeniz Infotech 36, 100 Feet Road, Natesan Nagar, Near Indira Gandhi Statue, Pondicherry-605 005. Call: 0413-4205444, +91 9566355386, 99625 88976. Web : www.lemenizinfotech.com / www.ieeemaster.com Mail : projects@lemenizinfotech.com damaged by excessive current when there is an overlap-time between switches S1 and S2 (or S3 and S4), because the input voltage will be short-circuited. Proposed system In this Project, very robust single-phase PWM ac–ac converters without the commutation problem are introduced. The proposed converters use basic switching cell structure and coupled inductors to implement phase legs of the converter. With this structure, the proposed converters can tolerate both dead-time and overlap-time without damaging switching devices. In addition, the proposed converters do not need to sense the voltage or current polarity for commutation. Therefore, highly robust and reliable PWM ac–ac converters can be developed.
- 3. Do Your Projects With Domain Experts… Copyright © 2015 LeMeniz Infotech. All rights reserved Page number 3 LeMeniz Infotech 36, 100 Feet Road, Natesan Nagar, Near Indira Gandhi Statue, Pondicherry-605 005. Call: 0413-4205444, +91 9566355386, 99625 88976. Web : www.lemenizinfotech.com / www.ieeemaster.com Mail : projects@lemenizinfotech.com Advantages Stable operation even when the input voltage is highly distorted. Applications AC drives Wind power applications
- 4. Do Your Projects With Domain Experts… Copyright © 2015 LeMeniz Infotech. All rights reserved Page number 4 LeMeniz Infotech 36, 100 Feet Road, Natesan Nagar, Near Indira Gandhi Statue, Pondicherry-605 005. Call: 0413-4205444, +91 9566355386, 99625 88976. Web : www.lemenizinfotech.com / www.ieeemaster.com Mail : projects@lemenizinfotech.com Block diagram COUPLED INDUCTOR 1 TOP LEG CONVERTER 1 LOAD INPUT AC SUPPLY PIC CONTROLLER WITH BUFFER DRIVER CIRCUIT 5V DC 12V DC COUPLED INDUCTOR 2 BOTTOM LEG CONVERTER 2
- 5. Do Your Projects With Domain Experts… Copyright © 2015 LeMeniz Infotech. All rights reserved Page number 5 LeMeniz Infotech 36, 100 Feet Road, Natesan Nagar, Near Indira Gandhi Statue, Pondicherry-605 005. Call: 0413-4205444, +91 9566355386, 99625 88976. Web : www.lemenizinfotech.com / www.ieeemaster.com Mail : projects@lemenizinfotech.com Tools and software MPLAB – microcontroller programming. ORCAD – circuit layout. MATLAB/Simulink – Simulation.