Integration and Operation of Fuel Cell and Gas Heating System by Fuzzy Logic Control

Abstract

Generation and consumption of heat power for domestic demand should consider economical and ecological aspects. Integration of the Fuel Cell System (FCS) for heat and electrical power generation into classical building heating systems enables the user to consider the environmental aspects. Hydrogen powered FCS as a source of clean and renewable energy replaces or reduces the classically employed fossil and Gas Heating Systems (GHS). This is the most important motivation for using FCS as a renewable energy source, which reduces the environmental pollution and ensures the demand for heating and electrical energy is met.

By evaluating the thermal behavior of the building and the heating system, Fuzzy Logic Control System (FLCS) provides a powerful rule base for decision-making and guarantees optimal operation of the FCS and the GHS. Additionally, FLCS reduces the switching frequency for both FCS and GHS, which is very important for the maintenance and operational life of the system. As a result, FLCS ensures a low emission operational mode of the GHS. FLCS is also responsible for optimal evaluation of heat power demand. Overall, the entire system consists of three different fuzzy controllers, each responsible for a different function described as: a) Fuzzy Proportional Integral Derivative (PID) Controller for heating water supply temperature; b) a Fuzzy Controller for optimal evaluation of heat power demand; and c) a Fuzzy Controller for the operation of the FCS and GHS with high efficiency and lowest switching frequency.