Performance Analysis of a DQ0 Controlled Grid Forming Inverter for Grid Connected Photovoltaic System: A Case Study

SMC Algorithms in T-Type Bidirectional Power Grid Converter

“…This work focuses on the simulation studies of proposed sliding mode control systems, which perform the task of controlling the main grid current in the structure of an inverter connected via an LCL filter to the power grid. The sinusoidal signals present in the three-phase system have been subjected to dq0 transformations, which allow for the simplification of the control system and maintain frequency synchronization with the power grid [7,[34][35][36]. The control algorithms presented in the further part of the work allow for full-range regulation of the d and q components of the grid current vector.…”

“…Figure 1 presents a simplified diagram of a bidirectional inverter in T topology, which cooperates with a DC voltage source through a capacitive filter. This source can, for example, constitute energy storage in a so-called microgrid with renewable energy devices [1][2][3][4][5][6][7].…”

“…The increasing number of different devices connected to the power grid means that the variability of power grid load is increasing. The number of so-called microgrids, i.e., local electrical grids, often equipped with energy storage and renewable energy sources such as photovoltaic panels [1][2][3][4][5][6][7], is growing. These structures mainly cooperate with the power grid, but they can also work in an island mode, i.e., disconnected from the main power grid [1][2][3][4][8][9][10][11].…”

“…In this work, a model of a structure, which includes a T-type three-level inverter connected to the power grid through an LCL filter [4][5][6][7][17][18][19][20], was proposed. In the literature, it is possible to find several examples of implementation of various three-phase inverter control algorithms that ensure improvement of the quality of transmitted energy.…”