Three-phase grid-connected inverter double closed loop

Is a grid-connected inverter control strategy feasible?

Through the theoretical analysis of the grid-connected inverter control principle, the grid-connected inverter control model is designed, and the transfer function model of each control link is deduced, and the current loop PI regulator is designed at last. The simulation results show that the control strategy is feasible.

What is a double closed-loop control strategy?

Meanwhile, a double closed-loop control strategy is utilized to eliminate the resonance introduced by the LCL filter and stabilize the system. Simulation and practical experiments are conducted with a detailed comparison between the discrete and integrated LCL filters, which can verify the feasibility and validity of the proposed method.

What are the disadvantages of a current double closed loop PI current tracking control?

In view of the disadvantages of the slow response speed of the traditional current control and the failure to eliminate the influence of the LCL filter on the grid-connected current by using current PI control alone, a current double closed loop PI current tracking control is proposed.

Can harmonic filters be integrated in a three-phase inverter system?

Actually, studies that investigate the magnetic integration design of harmonic filters in three-phase inverter system are limited. In , an integrated three-phase LCL filter is designed with EE core for a high-power inverter.

What is the output phase voltage of the inverter system?

Figure 13 presents the output phase voltage of the inverter system with double closed-loop control, which shows a standard fundamental phase voltage (225 V) with 2.5 kW rated output power. Output currents of the inverter system: a with integrated LCL filter; b with traditional discrete LCL filter.

What is a balanced three-phase inverter?

In a balanced three-phase inverter, the sum of the currents in the three phases is 0. Thus, the magnetic fluxes generated by the three phases can eliminate one another. Based on this, the inductors can be integrated in an EIE core unit, with the I-type core acting as the shared part.