Development of 100% Producer Gas Engine and Field Testing with PID Governor Mechanism for Variable Load Operation

With increasing scarcity of power and fossil fuel sources along with increasing concern about environmental degradation, there is renewed interest in biomass based energy systems. Biomass gasifier-based power generating systems operating with 100% producer gas engine are gaining importance as promising technology for remote village electrification in India. However, the major bottleneck hampering for the acceptability of dedicated gas engine based power plants is suitable governing mechanism for variable load operation under field conditions. Presently biomass gasifier-based power plants are being used mainly for fixed load operations with manual adjustments of valves for controlling gas-air mixture supply to engine for given load conditions. This paper gives a detailed account of efforts made in evolving robust engine governing mechanism (for maintaining engine speed and output frequency) under variable load operation for dedicated producer gas engine and its performance under field conditions. Results show that the present PID (proportional integrative and derivative) controller provides best control of engine speed (RPM), and are capable of maintaining the output frequencies and voltages within allowable narrow limits with fluctuating/oscillating load conditions.