Improved repetitive control scheme for grid‐connected inverter with frequency adaptation

Abstract

Fractional-order repetitive control (FORC) based on fractional delay filter has been used to deal with the timevarying periodic references due to its simpleness and easiness to implement. However, the FORC schemes have been designed to compensate selective harmonics to gain fast transient response, which will result in poor suppression effect on other-order harmonics. Thus, in this study, an improved frequency adaptive FORC is put forward to track or reject the time-varying periodic signals. A proportional channel is used in parallel with repetitive control to improve the transient response. Furthermore, the steady-state and dynamic performances of the proposed scheme are analysed. A experimental inverter platform based on MATLAB/Simulink and QuaRC is used to validate the effectiveness of the proposed control strategy. The experimental results obtained verify that the improved adaptive repetitive control can minimise the period harmonic distortion and has good dynamic response.

Observer‐based tracking control for switched stochastic systems based on a hybrid 2‐D model

“…Remark It should be mentioned that, in this paper, a new robust EID estimator–based repetitive control design for a class of linear switched stochastic systems with time delay and disturbance has been proposed. The authors in Lee and Zhao proposed a repetitive control design for continuous conduction mode and grid connected inverter systems, respectively, which can effectively track the periodic reference signals and reject the periodic disturbances. It is noting that if a control system is affected by aperiodic disturbances, the controller proposed in Lee and Zhao does not invoke properly.…”

“…Because of its eminent properties such as easy execution and high control precision, RC has been widely applied for various practical systems such as single-phase bidirectional rectifier, flyback continuous conduction mode inverter, grid-connected inverter, and robotic manipulators. [34][35][36][37] Repetitive controller with high-precision tracking property is due to a periodic signal generator implemented in the repetitive controller. Moreover, RC involves 2 types of independent actions: the continuous control process within 1 period and the discrete learning behavior between periods.…”

Control of distributed generation systems for microgrid applications: A technological review

“…So to rectify issues, RC may be shared with extremely dynamic reply controllers by shunt or in a series manner. In the paper, an improved fraction adaptive fractional‐order RC (FORC) scheme is designed by Zhao et al to recompense selective harmonics to improve faster transient response. This RC controller has the capability to trace or reject the time‐varying periodic waves.…”

Voltage Harmonic Suppression by Means of Grid-Connected Converters Using only Local Measurements

“…The commonly called harmonic compensation strategies of a shunt grid-connected converter can be separated into three categories. The first category is focused on improving its immunity to harmonic disturbances coming from the grid and load and overcoming the non-linearities of the converter itself in order to inject sinusoidal current into the grid [6][7][8]. The second category is devoted to absorbing harmonics caused by polluting loads by acting as an active power filter (APF) [5].…”