The Secondary Frequency Control Strategy for Inland Container Port Microgrids Based on Model-Free Adaptive Iterative Learning Control

In response to the frequency deviation exceeding limits caused by load fluctuations at inland container ports due to the rapid start-stop operations of handling equipment and frequent load switching, as well as the pulse-type dynamic disturbances faced by the microgrid due to load shedding, which make it difficult to design a secondary frequency controller using accurate data models, this paper proposes a secondary frequency control strategy for inland container port microgrids based on model free adaptive iterative learning control. The rotor motion equation of the virtual synchronous generator is discretized, and a dynamic linearization method with a compact format in the iterative domain is used to obtain the data model on the iteration axis, representing the discrete relationship between the virtual synchronous generator’s output angular frequency and the virtual input mechanical power. An iterative parameter update algorithm is presented, and the virtual synchronous generator control strategy is improved using model-free adaptive iterative learning control. The secondary frequency control scheme for inland ports under the load characteristics of inland container ports is proposed, and a secondary frequency control system for the inland port microgrid is constructed. Finally, the accuracy of the proposed control strategy is verified through simulations.