Modeling and Control of Single-Phase LCL-type Grid-connected Inverter in Discrete Domain

The power electronics control system can be designed in the discrete domain or continuous domain. In consideration of the digitally control and delay of actual system, it is more accurate to design the system control parameters in discrete domain. This paper firstly establishes the discrete domain model of the system, then analyzes stability of the system in the discrete domain, specifically designs the control parameters. After that verifies the correctness of the discrete domain design scheme through simulation in MATLAB. With relatively universal adaptability, the design process of control parameters researched in this paper provides reference for designing of the controller of the grid-connected inverter in discrete domain.