Design Research Of Control System For 60kW Gas Engine Using Biomass Gas

As one kind of the earliest energy people used - biology mass energy has received much attention of various countries all over the world once again in recent years because it is renewable and its pollution is very low. Gasification is the most effective way to change biomass mass energy into efficient ,clean and high-grade energy. And then biomass gas can be used as fuel of boilers, gas turbines,and internal combustion gas engine. We have inherent advantages in using biomass gas as an alternative fuel of internal combustion engine in our country which is a big agricultural one traditionally. But biomass gas/s calorific value is low , its combustion characteristics is different from those of conventional fuels.So if we want to use it in spark ignition engine ,we should do further research and improvement on the combustion characteristics and control characteristics of the internal combustion engine.Bcause of its own chacteristics, the biomass gas internal combustion engines is improved to use basing on conventional gas internal combustion engine.60KW biomass gas internal combustion engine selects 6126 engine as its model . Biomass gas/s calorific value is low,so it is hard to inginte.So the requirements of control system are higherIn this paper the technical parameters and the principle of the structure of the generater is expounded simplely,and its control strategies are researched.The main parts of the controlling system contain control modules ,control panels and electronic control mixer. Control module is designed optimally in the signal acquisition of temperature and pressure, and other parameters. The W77E58 and AT89S52 CPUs are used as central controller CPUs to process and analysis the collection of the information, and then the control signal is transfered out. The control panel is the main devices of the control system, which can achieves acquisition of the comprehensive parameters and controlling by computer, including water temperature, oil pressure, cylinder temperature, exhaust temperature and power parameters, and multiple protection can be achieved at gating, parking, and long-range communications capabilities. Electronic control mixer is implementing agency of the control system .This paper targets the characteristics of biomass gas which contains low calorific value and changes of composition of biomass gas and its combustion characteristics to designed a special electronic control mixer, whose main function is to provide engines with combustible gas mixture to suit different working conditions . Its principle is based on setting power points to analysis theory air-fuel ratio. Actual air-fuel ratio is compared with stoichiometric air-fuel ratio, and its deviation is used to adjust the opening of the gas and air volume changes. The value of mixer opening adjusting is output by PID algorithm so that the generator can run at the required power point stably. In order to verify the control system reliability, durability testing is implemented in Jinan biomass Institute. Test results show that the design of control system is rational and effective.