Design of Output Power Control Systems based on Mass Flow Rate Comparison of Air-Fuel Ratio (AFR) on Dual Fuel Generator Set by using the PID Control Method

Currently, biogas as an alternative fuel has been widely used in the community, including in lamps and biogas stoves. There has been a surplus of biogas in some production regions due to a relatively small need for biogas fuel. So that most biogas users utilize the surplus to become generator fuel. Yet, in the application there is a drawback, namely the instability of the electric power generated per unit time. This is caused by not achieving the optimal water-fuel ratio because the volume of biogas production from the reactor is fluctuating based on the volume of raw material, such as processed cow dung. Therefore, a control method using a PID Controller is constructed to determine the best value of the AFR on a dual fuel generator. The objective is to generate an optimal output of electric power. The generator set is a tool used to generate energy or electrical power. The electric power generated by the generator set used to supply the electrical loads in this research are lamps. Power produced by a generator set ranges from 100 to 1200 watts. The power generated by the generator set is affected by a mixture of air and fuel. The generator set is dual fuel. From the results of this study, a stable response with an overshoot value is below 0% and its error is 2%. In addition, the best-obtained value of the AFR is 15.06. Furthermore, the stability of the power generated by the generator set is also influenced by the flow rate mass of the fuel injected into the combustion chamber. From the simulation results, when given a power set point at 1200 watts, the obtained value of the air mass flow rate is 0.03754 kg/s, the mass flow rate of biogas is 0.002367 kg/s, and the gasoline constant mass flow rate is 0.000125 kg/s. Meanwhile, when given a set point of 100 watts and a value of 0.009928 kg/s air mass flow rate is injected into the chamber, the mass flow rate of biogas is 0.0005341 kg/s, and the mass flow rate of gasoline is 0.000125 kg/s. In this research, the value of AFR for complete combustion on a dual fuel system is 15.06. The results have shown that the PID Controller has been successfully implemented to regulate AFR, and the generator output of power can be constant.