AC-DC-AC Converter Example Demonstrating Universal Bridge Implementation

An AC-DC-AC converter represents a fundamental power electronics topology primarily utilized for converting alternating current to direct current and subsequently inverting it back to AC power. This configuration finds extensive applications in variable-frequency drives and uninterruptible power supply (UPS) systems.

Within the Simulink simulation environment, the Universal Bridge module enables rapid modeling of such converters. The Universal Bridge is a highly configurable bridge circuit block supporting multiple switching devices (such as IGBTs, MOSFETs) and topological configurations (including two-level or three-level designs). Through appropriate parameter configuration in the block's property inspector, engineers can efficiently implement combined AC-DC rectification and DC-AC inversion functions. The module's configuration dialog allows selection of switch types, number of bridge arms, and snubber circuit parameters.

Simulation setups typically incorporate Multimeter modules for monitoring key electrical parameters (voltage, current, power), while Powergui serves as Simulink's core tool for power system dynamic analysis, supporting frequency-domain analysis and harmonic computation through its FFT analysis capabilities. The Powergui block configuration includes options for specifying simulation type (continuous or discrete) and solver settings.

For control system implementation, discrete control modules (such as components from the Extras library) facilitate PWM generation algorithms and closed-loop regulation strategies. Discrete control more accurately represents actual digital controller behavior compared to continuous control, enhancing simulation fidelity. This modeling approach particularly validates control algorithm feasibility for practical hardware implementation (DSP or FPGA platforms), where developers can configure sampling times and discrete controller parameters to match target hardware specifications.

This modular modeling methodology enables comprehensive evaluation of system steady-state and dynamic performance prior to physical hardware development, significantly reducing project risks through simulation-based verification of control logic and power circuit interactions.