Analysis of a novel bidirectional DC-to-AC inverter

The switch-mode DC-to-AC inverter using a DC-to-DC converter configuration has many advantages over the traditional bridge-type inverter. The previously presented circuit with nonlinear robust control works only for resistive load and its output voltage has considerable distortion near the zero-crossing point. A novel bidirectional circuit with nonlinear robust control is proposed in this paper to overcome those drawbacks. This inverter can dynamically stabilize the output voltage, i.e., the output voltage of the inverter remains dynamically unchanged when subjected to large disturbances in the input voltage or output load. The stability analysis is presented. The closed-loop control system under P control, PI control, PD control, and PID control of the voltage loop for different types of loads are investigated. The results show that the PD control is the best choice. The performance of the circuit is also studied. Computer simulation and experimental results are provided.