Research On Nonlinear Robust Control Of Small Gas Internal Combustion Turbine Generators

The traditional way of thermal power generation and diesel power generation in some smaller power systems are mainly using fossil fuels to generate electricity. However, with the rapid development of society and the growing demand for electricity, these traditional power generation approaches will undoubtedly lead to serious environmental problems. Internal combustion engines are widely used in industry and agriculture in many aspects, gas internal combustion turbine generator has great development potential, for it uses environmentally friendly clean energy(natural gas, etc) as fuel, which can reduce the pollution of environment, and has some advantages such as small size, reliable operation, and high power generation efficiency. Based on the establishment of a gas internal combustion turbine generator model, this paper studied the use of extended state observer to improve the quality of the gas combustion turbine dynamic nonlinear robust control techniques, and simulation analysis was carried out in one machine infinite system and offshore platforms multi-machine system.Firstly, the working principle of the internal combustion engine was simply introduced in this paper, and the air-fuel ratio control and the ignition advanced angle control method in the speed control system were also described. Based on its working process, combined with the steam turbine modeling method, the gas internal combustion engine and speed control system were modeled in the DIgSILENT/Powerfactory, and its effectiveness was verified by simulation in a infinite system connected with one gas internal combustion turbine generator, whose parameter was provided by a manufacturer.Then, the parameter design method of the extended state observer(ESO) when applied to any order system was introduced in this paper, in this method, as long as the pole configuration of compensation matrix is reasonable, the ESO can quickly track system state changes without overshoot, and can estimate uncertainty changes of system model and external disturbances in real-time precisely. Based on the extended state observer, the nonlinear robust control technology was studied. Combined with the linear optimal control theory, the nonlinear system could be simplified to a linear system for control design, and simulation examples were given. The nonlinear robust control technique based on extended state observer was used for the additional throttle control and the additional excitation control of the gas internal combustion generator. And the simulation analysis was carried out in a one machine infinite system.Finally, three platforms of a offshore platform grid were chosen as research object system, in which six gas internal combustion turbine generators were connected to constitute a multi-machine system. The additional throttle control and additional excitation control system designed with nonlinear robust control were applied to the control system of the gas internal combustion turbine generators in the multi-machine system. The controller designed was simulated under different conditions. Simulation results show that the controller was preferably to improve the system stability and robustness.