Research On Digital Physical Hybrid Simulation Of Control Of Double Fed Wind Power Generation System

With the continuous increase of the total installed capacity and grid-connected capacity stand-alone capacity in China,higher demand for efficiency of wind power operation and fault through technology have been wanted accordingly.To select the expensive wind power systems which run actually with complex structure is neither convenient nor economical.In order to ensure the safe and stable operation of wind power generation system,it is necessary to choose a reasonable and effective simulation method to study the control technology.Digital physical hybrid simulation technology has some advantages of digital simulation and physical simulation simultaneously and save development time and hardware cost.It has been one effective method to study features and operation control of wind power generation system.This paper introduces the research status of wind power generation technology and composition,runtime principle of doubly fed wind power generation system.The simulation of wind power generation control system is summarized and several main control methods of doubly fed wind power generator are analyzed.The model of double fed wind power generation system is established and detailed study of the back-to-back PWM converter and its control system has been taken.Grid-connection control strategy and maximum power tracking control strategy has been derived.Decoupling control of stator active and reactive power based on stator voltage orientation.Typical cases of several commonly used low voltage ride through technologies which have been analyzed in this paper focusing on the principle of Crowbar protection circuit control.Relevant theories of digital physical hybrid simulation were studied;the basic principle and the main interface types of hybrid simulation were introduced.One set of hybrid simulation system based on RTDS were developed including designing the digital side and physical side.Data between the two sides are transmitted through GTIO boards.The main circuit and converter control program and the Crowbar protection circuit are designed in digital side and the physical side system consists of controller hardware and related interface circuit and control program.Hybrid simulation experiments on no-load grid connection,maximum power point tracking and LVRT have been done using the digital physical hybrid simulation system.The experiments results have been analyzed to sum up the effects of grid-connection on wind power generation system under different wind speeds and confirm the effectiveness of control strategy applied to doubly fed wind power generation system.