Abstract:
Application of dual fuel powered electric generators such as one of diesel and biogas
has gained popularity locally both as emergency power supply units and in
distributed power systems. Dual fuel generators use two fuel types simultaneously
in their operations. This is however faced with challenges in control and fuel
regulation since their operation must be economically feasible and convenient. To
achieve this, an intelligent controller that regulates generator operations is
necessary. This research work, set to determine operation characteristic of these
generators and fuel‐load relationship of the dual fuel engines in order to design a
control system for a dual fuel power generator system. Generator characteristics
such as fuel consumption on various loads were obtained through experiments; it
was found that injection of biogas in diesel engine saves diesel consumption by
approximately 30% on low load and 60% on high load.
The presented model switches the generator when needed and adjusts biogas inlet
in steps proportional to the load. It works by monitoring load, injecting a small
volume of biogas for loads below 10% and increasing it as the load increases to
maximum possible volume for load above 80%. The model was tested through
simulation of the obtained data on a Siemens ™ micro Logic controller
demonstrating a solution to control challenges. This model logic for control and
offers advanced logic electronic control for local applications. It is essential in
providing a versatile solution for a middle sized diesel biogas dual fuel power
generator control.
