The Research On Modeling And Simulation Of The Single Shaft Micro-turbine System Based On Stability Analysis

Micro-turbine possesses advantages of high efficiency and low pollution inenergy utilization, and can satisfy different kinds of energy demands of users.Especially the single shaft micro-turbine, although with complex structure, is typicallyused as a distributed source，which needs power electronic interface to converter thehigh-frequency energy to industry-frequency power. The spring up and developmentof distributed generation provides a flexible operation platform for micro-turbine,which can flexibly meet the demands of the cooling and heating power loads.Focusing on the structure and control system of single shaft micro-turbine, fourrelated research jobs are proceeded on in this paper:(1) A research on the structure of single shaft micro-turbine is carried on, basedon which the detailed model for stability analysis is proposed.(2) The circuit topology of the PWM converter is presented and the steady modelof the PWM converter for stability analysis is derived from the switching model.Furher more, based on the concept of microgrid, control strategies for PWM converterare explored both in grid-connected mode and isolated mode, especially the vertorcontrol strategy, which is described in detail.(3) Numerical solutions of ordinary differential equations suitable for stabilityanalysis are discussed and recurrence formulas are derived. Taking a distributionsystem including a micro-turbine as the case, the basic procedure for stability analysisis listed, according to which models of micro-turbine system are developed with C++.(4) Investigations on dynamic performance of the single shaft micro-turbine areproceeded on in case of a series of operations such as load fluction based on a18nodes distribution system. Furthermore, comprision of simulation results with thecommercial software DIgSILENT verifies the effectiveness and correctness of thepresented models which are developed with C++in this paper.