A single-phase direct buck-boost AC-AC converter with minimum number of components

Area of Science:

• Electrical Engineering
• Power Electronics

Background:

• AC-AC converters are crucial for power quality.
• Existing converters often face challenges with efficiency and component count.
• Voltage sags and swells degrade power quality and require effective compensation.

Purpose of the Study:

• To propose a novel single-phase direct pulse width modulation (PWM) buck-boost AC-AC converter.
• To demonstrate its high efficiency and reduced component count.
• To highlight its suitability for voltage sag and swell compensation.

Main Methods:

• Development of a single-phase direct PWM buck-boost AC-AC converter topology.
• Analysis of converter operation, including continuous input/output currents.
• Simulation using MATLAB/Simulink and experimental validation with a laboratory prototype.

Main Results:

• The proposed converter achieves high efficiency with a minimal number of semiconductor switches and passive components.
• It operates with simple PWM control, avoiding soft-commutation strategies and shoot-through issues.
• Continuous input and output currents are supplied, enabling voltage sag and swell compensation.

Conclusions:

• The novel buck-boost AC-AC converter provides an efficient and robust solution.
• Its design simplifies control and enhances reliability.
• The converter is a viable option for power quality improvement applications.