Design of optimized flatness based active disturbance rejection controller for communication time delayed hybrid microgrid

Abstract

In an islanded hybrid microgrid, frequency deviation is caused by the intermittent nature of renewable resources and load variations. Maintaining nominal frequency requires the secondary controller to send a signal to the controllable energy sources so that supply and demand are synchronized. Time delays in the system's communication channels, however, can reduce its efficiency. To compensate for the system uncertainties, modeling error and variant nature of renewable resources, an optimized flatness based active disturbance rejection controller have been proposed. Mitigating the effects of communication delay in the system and to synchronize the inputs to the extended state observer, a smith predictor based low pass filter is employed. Furthermore, an improved beluga whale optimization (IBWO) technique is employed to tune the proposed controller gains. The comparative analysis of the proposed IBWO is performed with existing algorithms. Moreover, the proposed controller superiority over the standard PID and LADRC approach has been investigated by perturbation in renewable resources, uncertainty in parameters, variation and mismatch in communication delay. Simulation results provide the testimony for the efficient performance of the designed controller. Lastly, the proposed controller is further evaluated in multi microgrid environment.

Keywords

• Hybrid microgrid
• Active disturbance rejection control
• Beluga whale optimization
• Differential flatness
• Communication delay