Frequency control of a new topology in proton exchange membrane fuel cell/wind turbine/photovoltaic/ultra-capacitor/battery energy storage system based isolated networks by a novel intelligent controller

This paper proposes a new topology for hybrid isolated networks employing a wind turbine (WT), proton exchange membrane fuel cell (PEMFC), photovoltaic, ultra-capacitor (UC), and battery energy storage system (BESS). The PEMFC is used in parallel with the UC and BESS; a configuration that improves the performance of the PEMFC in terms of dynamic response and lifetime. The proposed topology of the PEMFC along with a new model of WT reduces the initial costs of the hybrid isolated network. Due to power demand fluctuations in isolated networks, to maintain the balance between power generation and consumption, intelligent and flexible control methods must be applied. The variations of the solar irradiance, of the wind speed, and of the power consumption in hybrid isolated networks render the classic controllers and even fuzzy controllers inefficient. To overcome this problem, we use a novel intelligent fuzzy controller which is optimized by the teaching-learning-based optimization method. In the structure of the new proposed controller, the range and place of membership functions are optimized to reduce network frequency oscillations and improve network frequency stability. The designed control methodology is evaluated in the proposed isolated network and its performance is compared with the fuzzy controller, proportional integral (PI) controller, and optimal PI controller. To demonstrate the effectiveness of the proposed control strategies, the above-mentioned detailed mathematical and dynamic models of the isolated network were integrated using MATLAB/Simulink. (C) 2014 AIP Publishing LLC.